Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Luis R. Rodriguez]

On Mon, Jun 26, 2017 at 07:28:12PM -0700, Vikram Mulukutla wrote:
> On 6/26/2017 10:33 AM, Luis R. Rodriguez wrote:
> > On Sat, Jun 24, 2017 at 02:39:51PM +0200, Greg KH wrote:
> > > Was it used because your version has taken so long to be
> > > submitted/reviwed?
> > 
> > Vikram would have a better idea as he is the one who authored it, but it
> > would seem this effort was in parallel to my own at that time.
> > 
> 
> I must shamefully admit that the story is a bit older - the patch I
> originally worked on was on a v3.4 based tree. 
 
Oh wow so we had *two* separate parallel efforts to simplify this code
somehow...

My earliest sysdata API was based on v4.2-rc5 [0], this was after we decided we
*wanted* to enable to pass more arguments for fw signing from the start, to
enable custom fw criteria, as my original fw signing effort was completely
transparent to the API and matched what we did with module signing [1], and
based on v4.1-rc3.

Only difference is you just worked on the internal data tossed around. I
provided a way to also use this for growing the API.

[0] 
https://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux-next.git/log/?h=20150805-sysdata
[1] 
https://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux-next.git/log/?h=fw-signing-v2-20150513

> We had been forward
> porting it until Stephen Boyd was kind enough (or tired of it) to take
> time out of his clock maintainer-ship and upstream the
> request_firmware_into_buf API. At that point of time it seemed that the
> 'desc' approach was unnecessary, and I agreed.

It was very much needed and it could have helped. Next time please just send
patches right away!

> So Luis's series came
> in much later and wasn't a factor in forward-porting the patches.
> While it does seem that the _internal_ implementation of
> firmware_class can be a bit friendlier to adding the features that
> are on their way, I can't say the same about the API being exposed to
> drivers in mainline; maintainers and folks with more experience in
> kernel API evolution are better equipped to answer that question.

I actually am not aware how seriously the postulation to the problem I decided
to take on is being considered here...

Some of it may seem straight forward to some based on experience, but due to
the size of the kernel inspired by my prior effort to study collateral
evolutions for both forward and backporting purposes, I've decided to take on
the problem in a bit different light.

Just as your primary reason for your changes was that "the number of things
being passed around between layers of functions inside firmware_class seemed a
bit untenable", I also believed that the way in which we were loosely growing
the firmware API through unnecessary collateral evolutions was untenable.

I will confess that growing the API was just one consideration, another long
term lofty goal also aims towards automatic test driver generation, and enough
is sprinkled on test_driver_data.c that I hope some could infer perhaps how
I started thinking that might be possible one day.

I'm happy to park such effort, so long as we just decide with a path forward so
we can move on and chug on. Perhaps in the future some folks may want to
re-evaluate and consider the approach a bit further.

  Luis

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Luis R. Rodriguez]

On Mon, Jun 26, 2017 at 07:28:12PM -0700, Vikram Mulukutla wrote:
> On 6/26/2017 10:33 AM, Luis R. Rodriguez wrote:
> > On Sat, Jun 24, 2017 at 02:39:51PM +0200, Greg KH wrote:
> > > Was it used because your version has taken so long to be
> > > submitted/reviwed?
> > 
> > Vikram would have a better idea as he is the one who authored it, but it
> > would seem this effort was in parallel to my own at that time.
> > 
> 
> I must shamefully admit that the story is a bit older - the patch I
> originally worked on was on a v3.4 based tree. 
 
Oh wow so we had *two* separate parallel efforts to simplify this code
somehow...

My earliest sysdata API was based on v4.2-rc5 [0], this was after we decided we
*wanted* to enable to pass more arguments for fw signing from the start, to
enable custom fw criteria, as my original fw signing effort was completely
transparent to the API and matched what we did with module signing [1], and
based on v4.1-rc3.

Only difference is you just worked on the internal data tossed around. I
provided a way to also use this for growing the API.

[0] 
https://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux-next.git/log/?h=20150805-sysdata
[1] 
https://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux-next.git/log/?h=fw-signing-v2-20150513

> We had been forward
> porting it until Stephen Boyd was kind enough (or tired of it) to take
> time out of his clock maintainer-ship and upstream the
> request_firmware_into_buf API. At that point of time it seemed that the
> 'desc' approach was unnecessary, and I agreed.

It was very much needed and it could have helped. Next time please just send
patches right away!

> So Luis's series came
> in much later and wasn't a factor in forward-porting the patches.
> While it does seem that the _internal_ implementation of
> firmware_class can be a bit friendlier to adding the features that
> are on their way, I can't say the same about the API being exposed to
> drivers in mainline; maintainers and folks with more experience in
> kernel API evolution are better equipped to answer that question.

I actually am not aware how seriously the postulation to the problem I decided
to take on is being considered here...

Some of it may seem straight forward to some based on experience, but due to
the size of the kernel inspired by my prior effort to study collateral
evolutions for both forward and backporting purposes, I've decided to take on
the problem in a bit different light.

Just as your primary reason for your changes was that "the number of things
being passed around between layers of functions inside firmware_class seemed a
bit untenable", I also believed that the way in which we were loosely growing
the firmware API through unnecessary collateral evolutions was untenable.

I will confess that growing the API was just one consideration, another long
term lofty goal also aims towards automatic test driver generation, and enough
is sprinkled on test_driver_data.c that I hope some could infer perhaps how
I started thinking that might be possible one day.

I'm happy to park such effort, so long as we just decide with a path forward so
we can move on and chug on. Perhaps in the future some folks may want to
re-evaluate and consider the approach a bit further.

  Luis

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Vikram Mulukutla]

On 6/26/2017 10:33 AM, Luis R. Rodriguez wrote:

On Sat, Jun 24, 2017 at 02:39:51PM +0200, Greg KH wrote:

On Sat, Jun 24, 2017 at 02:48:28AM +0200, Luis R. Rodriguez wrote:

On Fri, Jun 23, 2017 at 04:09:29PM -0700, Linus Torvalds wrote:
On Fri, Jun 23, 2017 at 3:43 PM, Luis R. Rodriguez 
 wrote:


Ah, yes! Here is what I believe seems to be the *crux* issue of 
these patch
series and I'm happy we have finally landed on it. Yes, indeed the 
new API
proposed here provides more flexibility, and it does so by 
embracing a
"data driven" API Vs the traditional procedural APIs we have seen 
for

*the firmware API*.


This has been going on forever. Everybody hates your data-driven 
one.


Before you, the only person who had expressed disdain here was Greg.


Very few people actually review code, you know that.


Using that logic, then of course "everybody" was *very* fitting ;)

Then again others who actually are working on extending the firmware 
API (Yi
Li), or maintaining vendor trees (Vikram), did express their opinions 
on the
current codebase and their appreciate for the changes I made, however 
this went

selectively unnoticed.


Things like that may be ok as an internal implementation, but even
there it's questionable if it then means a big disconnect between 
what

people actually use (the normal functional model) and the
implementation.


A vendor tree implemented their *own* solution and were willing to 
maintain
it despite this likely making it hard to port stable fixes. That I 
think says

a lot for a need...


What vendor tree?  Where was it shipped?


The msm-3.18 kernel [0], so assuming this goes to mobile devices, this 
could

mean millions of devices.

https://source.codeaurora.org/quic/la/kernel/msm-3.18/commit/drivers/base/firmware_class.c?h=msm-3.18=7aa7efd3c150840369739893a84bd1d9f9774319


Why was it external and how is it different from your patches?


As is typical with external trees -- it would seem Vikram actually 
wrote the
original request_firmware_into_buf() API for the msm tree.  It 
contained the
fw_desc changes. Stephen Boyd seems to have worked on the actual 
upstreaming

effort and he dropped that fw_desc effort from the upstreaming effort.

Vikarm noted he had had a similar internal discussion with Stephen 
Stephen Boyd
as I am with you on this thread back when request_firmware_into_buf() 
was being
upstreamed [0]. He noted that back then reason for this proposed change 
was
that "the number of things being passed around between layers of 
functions
inside firmware_class seemed a bit untenable". I will note around that 
time I
had proposed a similar change using the fw_desc name, it was only later 
that
this renamed to a params postfix as Linus did not like the descriptor 
name.


[0] 
https://lkml.kernel.org/r/20ac6fa65c8ff4ef83386aa1e8d5c...@codeaurora.org


The only difference is that his patch does only modifying the private 
members

of the internal API and routines from my patch 1/5, and he kept the
"descriptor" name Linus disliked a while ago. This is precisely why 
AKASHI
noted I could split up my patch 1 in more ways in this series to help 
*patch

review*.

Was it used because your version has taken so long to be 
submitted/reviwed?


Vikram would have a better idea as he is the one who authored it, but 
it would

seem this effort was in parallel to my own at that time.



I must shamefully admit that the story is a bit older - the patch I
originally worked on was on a v3.4 based tree. We had been forward
porting it until Stephen Boyd was kind enough (or tired of it) to take
time out of his clock maintainer-ship and upstream the
request_firmware_into_buf API. At that point of time it seemed that the
'desc' approach was unnecessary, and I agreed. So Luis's series came
in much later and wasn't a factor in forward-porting the patches.
While it does seem that the _internal_ implementation of
firmware_class can be a bit friendlier to adding the features that
are on their way, I can't say the same about the API being exposed to
drivers in mainline; maintainers and folks with more experience in
kernel API evolution are better equipped to answer that question.

Thanks,
Vikram

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Vikram Mulukutla]

On 6/26/2017 10:33 AM, Luis R. Rodriguez wrote:

On Sat, Jun 24, 2017 at 02:39:51PM +0200, Greg KH wrote:

On Sat, Jun 24, 2017 at 02:48:28AM +0200, Luis R. Rodriguez wrote:

On Fri, Jun 23, 2017 at 04:09:29PM -0700, Linus Torvalds wrote:
On Fri, Jun 23, 2017 at 3:43 PM, Luis R. Rodriguez 
 wrote:


Ah, yes! Here is what I believe seems to be the *crux* issue of 
these patch
series and I'm happy we have finally landed on it. Yes, indeed the 
new API
proposed here provides more flexibility, and it does so by 
embracing a
"data driven" API Vs the traditional procedural APIs we have seen 
for

*the firmware API*.


This has been going on forever. Everybody hates your data-driven 
one.


Before you, the only person who had expressed disdain here was Greg.


Very few people actually review code, you know that.


Using that logic, then of course "everybody" was *very* fitting ;)

Then again others who actually are working on extending the firmware 
API (Yi
Li), or maintaining vendor trees (Vikram), did express their opinions 
on the
current codebase and their appreciate for the changes I made, however 
this went

selectively unnoticed.


Things like that may be ok as an internal implementation, but even
there it's questionable if it then means a big disconnect between 
what

people actually use (the normal functional model) and the
implementation.


A vendor tree implemented their *own* solution and were willing to 
maintain
it despite this likely making it hard to port stable fixes. That I 
think says

a lot for a need...


What vendor tree?  Where was it shipped?


The msm-3.18 kernel [0], so assuming this goes to mobile devices, this 
could

mean millions of devices.

https://source.codeaurora.org/quic/la/kernel/msm-3.18/commit/drivers/base/firmware_class.c?h=msm-3.18=7aa7efd3c150840369739893a84bd1d9f9774319


Why was it external and how is it different from your patches?


As is typical with external trees -- it would seem Vikram actually 
wrote the
original request_firmware_into_buf() API for the msm tree.  It 
contained the
fw_desc changes. Stephen Boyd seems to have worked on the actual 
upstreaming

effort and he dropped that fw_desc effort from the upstreaming effort.

Vikarm noted he had had a similar internal discussion with Stephen 
Stephen Boyd
as I am with you on this thread back when request_firmware_into_buf() 
was being
upstreamed [0]. He noted that back then reason for this proposed change 
was
that "the number of things being passed around between layers of 
functions
inside firmware_class seemed a bit untenable". I will note around that 
time I
had proposed a similar change using the fw_desc name, it was only later 
that
this renamed to a params postfix as Linus did not like the descriptor 
name.


[0] 
https://lkml.kernel.org/r/20ac6fa65c8ff4ef83386aa1e8d5c...@codeaurora.org


The only difference is that his patch does only modifying the private 
members

of the internal API and routines from my patch 1/5, and he kept the
"descriptor" name Linus disliked a while ago. This is precisely why 
AKASHI
noted I could split up my patch 1 in more ways in this series to help 
*patch

review*.

Was it used because your version has taken so long to be 
submitted/reviwed?


Vikram would have a better idea as he is the one who authored it, but 
it would

seem this effort was in parallel to my own at that time.



I must shamefully admit that the story is a bit older - the patch I
originally worked on was on a v3.4 based tree. We had been forward
porting it until Stephen Boyd was kind enough (or tired of it) to take
time out of his clock maintainer-ship and upstream the
request_firmware_into_buf API. At that point of time it seemed that the
'desc' approach was unnecessary, and I agreed. So Luis's series came
in much later and wasn't a factor in forward-porting the patches.
While it does seem that the _internal_ implementation of
firmware_class can be a bit friendlier to adding the features that
are on their way, I can't say the same about the API being exposed to
drivers in mainline; maintainers and folks with more experience in
kernel API evolution are better equipped to answer that question.

Thanks,
Vikram

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Luis R. Rodriguez]

On Mon, Jun 26, 2017 at 08:19:07PM +0200, Rafał Miłecki wrote:
> On 2017-06-26 19:33, Luis R. Rodriguez wrote:
> > On Sat, Jun 24, 2017 at 02:39:51PM +0200, Greg KH wrote:
> > > > There are still other requirements and features in the pipeline for 
> > > > which we
> > > > can consider parameters to parse for, rather than adding new API. Case 
> > > > in
> > > > point, do we want *one* API just to disable the firmware cache? 
> > > > Specially
> > > > knowing that another feature in the pipeline later would make use of 
> > > > this as a
> > > > requirement?
> > > 
> > > Again, I do not care!  You can not justify patches today with some
> > > mythical thing in the future that might never even happen.
> > 
> > Granting the option to make async firmware optional was discussed since
> > December 2016 by RafaÅ [1]. It was only later during my driver data API
> > changes that Hans noted the nvram part was actually *not* optional [2] so
> > this requirement dropped. *However* as the maintainer I believ ethis
> > requirement *is sensible* and would not be surprised if alternative
> > firmware already exists where this is what is intended.
> 
> I believe there was a misunderstanding of my patch by Hans. The point of my
> patch was to don't display warning *IF* we can use alternative soruce and
> get the NVRAM (firmware) from platform data (special partition used by the
> bootloader and accessible by the operating system).

Oh, are you saying the optional async firmware loading is still a requirement
for this driver? Are you, Hans, and Arend Van Spriel in agreement on this?

If so then that definitely makes 3 effective changes in my radar for extensions
to the firmware API.

  Luis

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Luis R. Rodriguez]

On Mon, Jun 26, 2017 at 08:19:07PM +0200, Rafał Miłecki wrote:
> On 2017-06-26 19:33, Luis R. Rodriguez wrote:
> > On Sat, Jun 24, 2017 at 02:39:51PM +0200, Greg KH wrote:
> > > > There are still other requirements and features in the pipeline for 
> > > > which we
> > > > can consider parameters to parse for, rather than adding new API. Case 
> > > > in
> > > > point, do we want *one* API just to disable the firmware cache? 
> > > > Specially
> > > > knowing that another feature in the pipeline later would make use of 
> > > > this as a
> > > > requirement?
> > > 
> > > Again, I do not care!  You can not justify patches today with some
> > > mythical thing in the future that might never even happen.
> > 
> > Granting the option to make async firmware optional was discussed since
> > December 2016 by RafaÅ [1]. It was only later during my driver data API
> > changes that Hans noted the nvram part was actually *not* optional [2] so
> > this requirement dropped. *However* as the maintainer I believ ethis
> > requirement *is sensible* and would not be surprised if alternative
> > firmware already exists where this is what is intended.
> 
> I believe there was a misunderstanding of my patch by Hans. The point of my
> patch was to don't display warning *IF* we can use alternative soruce and
> get the NVRAM (firmware) from platform data (special partition used by the
> bootloader and accessible by the operating system).

Oh, are you saying the optional async firmware loading is still a requirement
for this driver? Are you, Hans, and Arend Van Spriel in agreement on this?

If so then that definitely makes 3 effective changes in my radar for extensions
to the firmware API.

  Luis

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Rafał Miłecki]

On 2017-06-26 19:33, Luis R. Rodriguez wrote:

On Sat, Jun 24, 2017 at 02:39:51PM +0200, Greg KH wrote:

On Sat, Jun 24, 2017 at 02:48:28AM +0200, Luis R. Rodriguez wrote:
> On Fri, Jun 23, 2017 at 04:09:29PM -0700, Linus Torvalds wrote:
> > On Fri, Jun 23, 2017 at 3:43 PM, Luis R. Rodriguez  
wrote:
> > >
> > > Ah, yes! Here is what I believe seems to be the *crux* issue of these 
patch
> > > series and I'm happy we have finally landed on it. Yes, indeed the new API
> > > proposed here provides more flexibility, and it does so by embracing a
> > > "data driven" API Vs the traditional procedural APIs we have seen for
> > > *the firmware API*.
> >
> > This has been going on forever. Everybody hates your data-driven one.
>
> Before you, the only person who had expressed disdain here was Greg.

Very few people actually review code, you know that.


Using that logic, then of course "everybody" was *very* fitting ;)

Then again others who actually are working on extending the firmware 
API (Yi
Li), or maintaining vendor trees (Vikram), did express their opinions 
on the
current codebase and their appreciate for the changes I made, however 
this went

selectively unnoticed.


> > Things like that may be ok as an internal implementation, but even
> > there it's questionable if it then means a big disconnect between what
> > people actually use (the normal functional model) and the
> > implementation.
>
> A vendor tree implemented their *own* solution and were willing to maintain
> it despite this likely making it hard to port stable fixes. That I think says
> a lot for a need...

What vendor tree?  Where was it shipped?


The msm-3.18 kernel [0], so assuming this goes to mobile devices, this 
could

mean millions of devices.

https://source.codeaurora.org/quic/la/kernel/msm-3.18/commit/drivers/base/firmware_class.c?h=msm-3.18=7aa7efd3c150840369739893a84bd1d9f9774319


Why was it external and how is it different from your patches?


As is typical with external trees -- it would seem Vikram actually 
wrote the
original request_firmware_into_buf() API for the msm tree.  It 
contained the
fw_desc changes. Stephen Boyd seems to have worked on the actual 
upstreaming

effort and he dropped that fw_desc effort from the upstreaming effort.

Vikarm noted he had had a similar internal discussion with Stephen 
Stephen Boyd
as I am with you on this thread back when request_firmware_into_buf() 
was being
upstreamed [0]. He noted that back then reason for this proposed change 
was
that "the number of things being passed around between layers of 
functions
inside firmware_class seemed a bit untenable". I will note around that 
time I
had proposed a similar change using the fw_desc name, it was only later 
that
this renamed to a params postfix as Linus did not like the descriptor 
name.


[0] 
https://lkml.kernel.org/r/20ac6fa65c8ff4ef83386aa1e8d5c...@codeaurora.org


The only difference is that his patch does only modifying the private 
members

of the internal API and routines from my patch 1/5, and he kept the
"descriptor" name Linus disliked a while ago. This is precisely why 
AKASHI
noted I could split up my patch 1 in more ways in this series to help 
*patch

review*.

Was it used because your version has taken so long to be 
submitted/reviwed?


Vikram would have a better idea as he is the one who authored it, but 
it would

seem this effort was in parallel to my own at that time.


> There are still other requirements and features in the pipeline for which we
> can consider parameters to parse for, rather than adding new API. Case in
> point, do we want *one* API just to disable the firmware cache? Specially
> knowing that another feature in the pipeline later would make use of this as a
> requirement?

Again, I do not care!  You can not justify patches today with some
mythical thing in the future that might never even happen.


Some of these features are things actually being discussed for a while, 
so to
say they are mythical is not accurate. I can trace back firmware 
signing
discussions back to 2015, along with Plumbers in person discussions 
where we
seem to have agreed upon a path forward among a few folks who disagreed 
on a
technical basis. Linaro has a clear interest so AKASHI picked up that 
work now
as I have been busy with general maintainer duties. The fact that Linus 
just
suggested an alternative approach to a params approach is new, and yet 
to be

reviewe by AKASHI for firmware signing.

Granting the option to make async firmware optional was discussed since
December 2016 by RafaÅ [1]. It was only later during my driver data API 
changes

that Hans noted the nvram part was actually *not* optional [2] so this
requirement dropped. *However* as the maintainer I believ ethis 
requirement *is
sensible* and would not be surprised if alternative firmware already 
exists

where this is what is intended.


I believe there was a misunderstanding of my patch by Hans. The point of 
my
patch was 

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Rafał Miłecki]

On 2017-06-26 19:33, Luis R. Rodriguez wrote:

On Sat, Jun 24, 2017 at 02:39:51PM +0200, Greg KH wrote:

On Sat, Jun 24, 2017 at 02:48:28AM +0200, Luis R. Rodriguez wrote:
> On Fri, Jun 23, 2017 at 04:09:29PM -0700, Linus Torvalds wrote:
> > On Fri, Jun 23, 2017 at 3:43 PM, Luis R. Rodriguez  
wrote:
> > >
> > > Ah, yes! Here is what I believe seems to be the *crux* issue of these 
patch
> > > series and I'm happy we have finally landed on it. Yes, indeed the new API
> > > proposed here provides more flexibility, and it does so by embracing a
> > > "data driven" API Vs the traditional procedural APIs we have seen for
> > > *the firmware API*.
> >
> > This has been going on forever. Everybody hates your data-driven one.
>
> Before you, the only person who had expressed disdain here was Greg.

Very few people actually review code, you know that.


Using that logic, then of course "everybody" was *very* fitting ;)

Then again others who actually are working on extending the firmware 
API (Yi
Li), or maintaining vendor trees (Vikram), did express their opinions 
on the
current codebase and their appreciate for the changes I made, however 
this went

selectively unnoticed.


> > Things like that may be ok as an internal implementation, but even
> > there it's questionable if it then means a big disconnect between what
> > people actually use (the normal functional model) and the
> > implementation.
>
> A vendor tree implemented their *own* solution and were willing to maintain
> it despite this likely making it hard to port stable fixes. That I think says
> a lot for a need...

What vendor tree?  Where was it shipped?


The msm-3.18 kernel [0], so assuming this goes to mobile devices, this 
could

mean millions of devices.

https://source.codeaurora.org/quic/la/kernel/msm-3.18/commit/drivers/base/firmware_class.c?h=msm-3.18=7aa7efd3c150840369739893a84bd1d9f9774319


Why was it external and how is it different from your patches?


As is typical with external trees -- it would seem Vikram actually 
wrote the
original request_firmware_into_buf() API for the msm tree.  It 
contained the
fw_desc changes. Stephen Boyd seems to have worked on the actual 
upstreaming

effort and he dropped that fw_desc effort from the upstreaming effort.

Vikarm noted he had had a similar internal discussion with Stephen 
Stephen Boyd
as I am with you on this thread back when request_firmware_into_buf() 
was being
upstreamed [0]. He noted that back then reason for this proposed change 
was
that "the number of things being passed around between layers of 
functions
inside firmware_class seemed a bit untenable". I will note around that 
time I
had proposed a similar change using the fw_desc name, it was only later 
that
this renamed to a params postfix as Linus did not like the descriptor 
name.


[0] 
https://lkml.kernel.org/r/20ac6fa65c8ff4ef83386aa1e8d5c...@codeaurora.org


The only difference is that his patch does only modifying the private 
members

of the internal API and routines from my patch 1/5, and he kept the
"descriptor" name Linus disliked a while ago. This is precisely why 
AKASHI
noted I could split up my patch 1 in more ways in this series to help 
*patch

review*.

Was it used because your version has taken so long to be 
submitted/reviwed?


Vikram would have a better idea as he is the one who authored it, but 
it would

seem this effort was in parallel to my own at that time.


> There are still other requirements and features in the pipeline for which we
> can consider parameters to parse for, rather than adding new API. Case in
> point, do we want *one* API just to disable the firmware cache? Specially
> knowing that another feature in the pipeline later would make use of this as a
> requirement?

Again, I do not care!  You can not justify patches today with some
mythical thing in the future that might never even happen.


Some of these features are things actually being discussed for a while, 
so to
say they are mythical is not accurate. I can trace back firmware 
signing
discussions back to 2015, along with Plumbers in person discussions 
where we
seem to have agreed upon a path forward among a few folks who disagreed 
on a
technical basis. Linaro has a clear interest so AKASHI picked up that 
work now
as I have been busy with general maintainer duties. The fact that Linus 
just
suggested an alternative approach to a params approach is new, and yet 
to be

reviewe by AKASHI for firmware signing.

Granting the option to make async firmware optional was discussed since
December 2016 by RafaÅ [1]. It was only later during my driver data API 
changes

that Hans noted the nvram part was actually *not* optional [2] so this
requirement dropped. *However* as the maintainer I believ ethis 
requirement *is
sensible* and would not be surprised if alternative firmware already 
exists

where this is what is intended.


I believe there was a misunderstanding of my patch by Hans. The point of 
my
patch was to don't display 

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Luis R. Rodriguez]

On Sat, Jun 24, 2017 at 02:39:51PM +0200, Greg KH wrote:
> On Sat, Jun 24, 2017 at 02:48:28AM +0200, Luis R. Rodriguez wrote:
> > On Fri, Jun 23, 2017 at 04:09:29PM -0700, Linus Torvalds wrote:
> > > On Fri, Jun 23, 2017 at 3:43 PM, Luis R. Rodriguez  
> > > wrote:
> > > >
> > > > Ah, yes! Here is what I believe seems to be the *crux* issue of these 
> > > > patch
> > > > series and I'm happy we have finally landed on it. Yes, indeed the new 
> > > > API
> > > > proposed here provides more flexibility, and it does so by embracing a
> > > > "data driven" API Vs the traditional procedural APIs we have seen for
> > > > *the firmware API*.
> > > 
> > > This has been going on forever. Everybody hates your data-driven one.
> > 
> > Before you, the only person who had expressed disdain here was Greg.
> 
> Very few people actually review code, you know that.

Using that logic, then of course "everybody" was *very* fitting ;)

Then again others who actually are working on extending the firmware API (Yi
Li), or maintaining vendor trees (Vikram), did express their opinions on the
current codebase and their appreciate for the changes I made, however this went
selectively unnoticed.

> > > Things like that may be ok as an internal implementation, but even
> > > there it's questionable if it then means a big disconnect between what
> > > people actually use (the normal functional model) and the
> > > implementation.
> > 
> > A vendor tree implemented their *own* solution and were willing to maintain
> > it despite this likely making it hard to port stable fixes. That I think 
> > says
> > a lot for a need...
> 
> What vendor tree?  Where was it shipped? 

The msm-3.18 kernel [0], so assuming this goes to mobile devices, this could
mean millions of devices.

https://source.codeaurora.org/quic/la/kernel/msm-3.18/commit/drivers/base/firmware_class.c?h=msm-3.18=7aa7efd3c150840369739893a84bd1d9f9774319
 

> Why was it external and how is it different from your patches?

As is typical with external trees -- it would seem Vikram actually wrote the
original request_firmware_into_buf() API for the msm tree.  It contained the
fw_desc changes. Stephen Boyd seems to have worked on the actual upstreaming
effort and he dropped that fw_desc effort from the upstreaming effort.

Vikarm noted he had had a similar internal discussion with Stephen Stephen Boyd
as I am with you on this thread back when request_firmware_into_buf() was being
upstreamed [0]. He noted that back then reason for this proposed change was
that "the number of things being passed around between layers of functions
inside firmware_class seemed a bit untenable". I will note around that time I
had proposed a similar change using the fw_desc name, it was only later that
this renamed to a params postfix as Linus did not like the descriptor name.

[0] https://lkml.kernel.org/r/20ac6fa65c8ff4ef83386aa1e8d5c...@codeaurora.org

The only difference is that his patch does only modifying the private members
of the internal API and routines from my patch 1/5, and he kept the
"descriptor" name Linus disliked a while ago. This is precisely why AKASHI
noted I could split up my patch 1 in more ways in this series to help *patch
review*.

> Was it used because your version has taken so long to be submitted/reviwed?

Vikram would have a better idea as he is the one who authored it, but it would
seem this effort was in parallel to my own at that time.

> > There are still other requirements and features in the pipeline for which we
> > can consider parameters to parse for, rather than adding new API. Case in
> > point, do we want *one* API just to disable the firmware cache? Specially
> > knowing that another feature in the pipeline later would make use of this 
> > as a
> > requirement?
> 
> Again, I do not care!  You can not justify patches today with some
> mythical thing in the future that might never even happen.

Some of these features are things actually being discussed for a while, so to
say they are mythical is not accurate. I can trace back firmware signing
discussions back to 2015, along with Plumbers in person discussions where we
seem to have agreed upon a path forward among a few folks who disagreed on a
technical basis. Linaro has a clear interest so AKASHI picked up that work now
as I have been busy with general maintainer duties. The fact that Linus just
suggested an alternative approach to a params approach is new, and yet to be
reviewe by AKASHI for firmware signing.

Granting the option to make async firmware optional was discussed since
December 2016 by RafaÅ [1]. It was only later during my driver data API changes
that Hans noted the nvram part was actually *not* optional [2] so this
requirement dropped. *However* as the maintainer I believ ethis requirement *is
sensible* and would not be surprised if alternative firmware already exists
where this is what is intended. 

The streaming support for FPGAs has been going through a round of reviews 

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Luis R. Rodriguez]

On Sat, Jun 24, 2017 at 02:39:51PM +0200, Greg KH wrote:
> On Sat, Jun 24, 2017 at 02:48:28AM +0200, Luis R. Rodriguez wrote:
> > On Fri, Jun 23, 2017 at 04:09:29PM -0700, Linus Torvalds wrote:
> > > On Fri, Jun 23, 2017 at 3:43 PM, Luis R. Rodriguez  
> > > wrote:
> > > >
> > > > Ah, yes! Here is what I believe seems to be the *crux* issue of these 
> > > > patch
> > > > series and I'm happy we have finally landed on it. Yes, indeed the new 
> > > > API
> > > > proposed here provides more flexibility, and it does so by embracing a
> > > > "data driven" API Vs the traditional procedural APIs we have seen for
> > > > *the firmware API*.
> > > 
> > > This has been going on forever. Everybody hates your data-driven one.
> > 
> > Before you, the only person who had expressed disdain here was Greg.
> 
> Very few people actually review code, you know that.

Using that logic, then of course "everybody" was *very* fitting ;)

Then again others who actually are working on extending the firmware API (Yi
Li), or maintaining vendor trees (Vikram), did express their opinions on the
current codebase and their appreciate for the changes I made, however this went
selectively unnoticed.

> > > Things like that may be ok as an internal implementation, but even
> > > there it's questionable if it then means a big disconnect between what
> > > people actually use (the normal functional model) and the
> > > implementation.
> > 
> > A vendor tree implemented their *own* solution and were willing to maintain
> > it despite this likely making it hard to port stable fixes. That I think 
> > says
> > a lot for a need...
> 
> What vendor tree?  Where was it shipped? 

The msm-3.18 kernel [0], so assuming this goes to mobile devices, this could
mean millions of devices.

https://source.codeaurora.org/quic/la/kernel/msm-3.18/commit/drivers/base/firmware_class.c?h=msm-3.18=7aa7efd3c150840369739893a84bd1d9f9774319
 

> Why was it external and how is it different from your patches?

As is typical with external trees -- it would seem Vikram actually wrote the
original request_firmware_into_buf() API for the msm tree.  It contained the
fw_desc changes. Stephen Boyd seems to have worked on the actual upstreaming
effort and he dropped that fw_desc effort from the upstreaming effort.

Vikarm noted he had had a similar internal discussion with Stephen Stephen Boyd
as I am with you on this thread back when request_firmware_into_buf() was being
upstreamed [0]. He noted that back then reason for this proposed change was
that "the number of things being passed around between layers of functions
inside firmware_class seemed a bit untenable". I will note around that time I
had proposed a similar change using the fw_desc name, it was only later that
this renamed to a params postfix as Linus did not like the descriptor name.

[0] https://lkml.kernel.org/r/20ac6fa65c8ff4ef83386aa1e8d5c...@codeaurora.org

The only difference is that his patch does only modifying the private members
of the internal API and routines from my patch 1/5, and he kept the
"descriptor" name Linus disliked a while ago. This is precisely why AKASHI
noted I could split up my patch 1 in more ways in this series to help *patch
review*.

> Was it used because your version has taken so long to be submitted/reviwed?

Vikram would have a better idea as he is the one who authored it, but it would
seem this effort was in parallel to my own at that time.

> > There are still other requirements and features in the pipeline for which we
> > can consider parameters to parse for, rather than adding new API. Case in
> > point, do we want *one* API just to disable the firmware cache? Specially
> > knowing that another feature in the pipeline later would make use of this 
> > as a
> > requirement?
> 
> Again, I do not care!  You can not justify patches today with some
> mythical thing in the future that might never even happen.

Some of these features are things actually being discussed for a while, so to
say they are mythical is not accurate. I can trace back firmware signing
discussions back to 2015, along with Plumbers in person discussions where we
seem to have agreed upon a path forward among a few folks who disagreed on a
technical basis. Linaro has a clear interest so AKASHI picked up that work now
as I have been busy with general maintainer duties. The fact that Linus just
suggested an alternative approach to a params approach is new, and yet to be
reviewe by AKASHI for firmware signing.

Granting the option to make async firmware optional was discussed since
December 2016 by RafaÅ [1]. It was only later during my driver data API changes
that Hans noted the nvram part was actually *not* optional [2] so this
requirement dropped. *However* as the maintainer I believ ethis requirement *is
sensible* and would not be surprised if alternative firmware already exists
where this is what is intended. 

The streaming support for FPGAs has been going through a round of reviews since
March [3]. The 

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Luis R. Rodriguez]

On Sat, Jun 24, 2017 at 02:40:57PM +0200, Greg KH wrote:
> On Sat, Jun 24, 2017 at 12:43:38AM +0200, Luis R. Rodriguez wrote:
> > > It's also blocking real bug fixes and features that people want
> > > addressed, which isn't acceptable.
> > 
> > What? What bugs ? I have addressed *every single* stable issue in queue and
> > have sent patches for them and they do not depend in any way on any of this
> > series!
> 
> Ok, so we are all caught up now with bug fixes?  That's good, I was not
> aware of that, so nevermind that objection, my fault.

Yes. I've been following up on all actively reported bugs and have even
implemented better alternatives based on discussions.

  Luis

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Luis R. Rodriguez]

On Sat, Jun 24, 2017 at 02:40:57PM +0200, Greg KH wrote:
> On Sat, Jun 24, 2017 at 12:43:38AM +0200, Luis R. Rodriguez wrote:
> > > It's also blocking real bug fixes and features that people want
> > > addressed, which isn't acceptable.
> > 
> > What? What bugs ? I have addressed *every single* stable issue in queue and
> > have sent patches for them and they do not depend in any way on any of this
> > series!
> 
> Ok, so we are all caught up now with bug fixes?  That's good, I was not
> aware of that, so nevermind that objection, my fault.

Yes. I've been following up on all actively reported bugs and have even
implemented better alternatives based on discussions.

  Luis

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Greg KH]

On Sat, Jun 24, 2017 at 12:43:38AM +0200, Luis R. Rodriguez wrote:
> > It's also blocking real bug fixes and features that people want
> > addressed, which isn't acceptable.
> 
> What? What bugs ? I have addressed *every single* stable issue in queue and
> have sent patches for them and they do not depend in any way on any of this
> series!

Ok, so we are all caught up now with bug fixes?  That's good, I was not
aware of that, so nevermind that objection, my fault.

greg k-h

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Greg KH]

On Sat, Jun 24, 2017 at 12:43:38AM +0200, Luis R. Rodriguez wrote:
> > It's also blocking real bug fixes and features that people want
> > addressed, which isn't acceptable.
> 
> What? What bugs ? I have addressed *every single* stable issue in queue and
> have sent patches for them and they do not depend in any way on any of this
> series!

Ok, so we are all caught up now with bug fixes?  That's good, I was not
aware of that, so nevermind that objection, my fault.

greg k-h

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Greg KH]

On Sat, Jun 24, 2017 at 02:48:28AM +0200, Luis R. Rodriguez wrote:
> On Fri, Jun 23, 2017 at 04:09:29PM -0700, Linus Torvalds wrote:
> > On Fri, Jun 23, 2017 at 3:43 PM, Luis R. Rodriguez  
> > wrote:
> > >
> > > Ah, yes! Here is what I believe seems to be the *crux* issue of these 
> > > patch
> > > series and I'm happy we have finally landed on it. Yes, indeed the new API
> > > proposed here provides more flexibility, and it does so by embracing a
> > > "data driven" API Vs the traditional procedural APIs we have seen for
> > > *the firmware API*.
> > 
> > This has been going on forever. Everybody hates your data-driven one.
> 
> Before you, the only person who had expressed disdain here was Greg.

Very few people actually review code, you know that.

> > Things like that may be ok as an internal implementation, but even
> > there it's questionable if it then means a big disconnect between what
> > people actually use (the normal functional model) and the
> > implementation.
> 
> A vendor tree implemented their *own* solution and were willing to maintain
> it despite this likely making it hard to port stable fixes. That I think says
> a lot for a need...

What vendor tree?  Where was it shipped?  Why was it external and how is
it different from your patches?  Was it used because your version has
taken so long to be submitted/reviwed?

> There are still other requirements and features in the pipeline for which we
> can consider parameters to parse for, rather than adding new API. Case in
> point, do we want *one* API just to disable the firmware cache? Specially
> knowing that another feature in the pipeline later would make use of this as a
> requirement?

Again, I do not care!  You can not justify patches today with some
mythical thing in the future that might never even happen.

Again, as it stands, this patch series is unacceptable, and the added
complexity of a crazy api that goes against almost all normal in-kernel
apis, is only one part of the reason.  The other being the loads of
added code for no apparent benifit at all.

So please both fix the api to be "normal", and show as to why these
patches are actually needed _today_, otherwise we can just live with
what we have now just fine and muddle along like always.

thanks,

greg k-h

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Greg KH]

On Sat, Jun 24, 2017 at 02:48:28AM +0200, Luis R. Rodriguez wrote:
> On Fri, Jun 23, 2017 at 04:09:29PM -0700, Linus Torvalds wrote:
> > On Fri, Jun 23, 2017 at 3:43 PM, Luis R. Rodriguez  
> > wrote:
> > >
> > > Ah, yes! Here is what I believe seems to be the *crux* issue of these 
> > > patch
> > > series and I'm happy we have finally landed on it. Yes, indeed the new API
> > > proposed here provides more flexibility, and it does so by embracing a
> > > "data driven" API Vs the traditional procedural APIs we have seen for
> > > *the firmware API*.
> > 
> > This has been going on forever. Everybody hates your data-driven one.
> 
> Before you, the only person who had expressed disdain here was Greg.

Very few people actually review code, you know that.

> > Things like that may be ok as an internal implementation, but even
> > there it's questionable if it then means a big disconnect between what
> > people actually use (the normal functional model) and the
> > implementation.
> 
> A vendor tree implemented their *own* solution and were willing to maintain
> it despite this likely making it hard to port stable fixes. That I think says
> a lot for a need...

What vendor tree?  Where was it shipped?  Why was it external and how is
it different from your patches?  Was it used because your version has
taken so long to be submitted/reviwed?

> There are still other requirements and features in the pipeline for which we
> can consider parameters to parse for, rather than adding new API. Case in
> point, do we want *one* API just to disable the firmware cache? Specially
> knowing that another feature in the pipeline later would make use of this as a
> requirement?

Again, I do not care!  You can not justify patches today with some
mythical thing in the future that might never even happen.

Again, as it stands, this patch series is unacceptable, and the added
complexity of a crazy api that goes against almost all normal in-kernel
apis, is only one part of the reason.  The other being the loads of
added code for no apparent benifit at all.

So please both fix the api to be "normal", and show as to why these
patches are actually needed _today_, otherwise we can just live with
what we have now just fine and muddle along like always.

thanks,

greg k-h

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Luis R. Rodriguez]

On Fri, Jun 23, 2017 at 04:09:29PM -0700, Linus Torvalds wrote:
> On Fri, Jun 23, 2017 at 3:43 PM, Luis R. Rodriguez  wrote:
> >
> > Ah, yes! Here is what I believe seems to be the *crux* issue of these patch
> > series and I'm happy we have finally landed on it. Yes, indeed the new API
> > proposed here provides more flexibility, and it does so by embracing a
> > "data driven" API Vs the traditional procedural APIs we have seen for
> > *the firmware API*.
> 
> This has been going on forever. Everybody hates your data-driven one.

Before you, the only person who had expressed disdain here was Greg.

> It's too indirect, it adds all those nasty "descriptors" of what to
> do, and it doesn't match what the current model does at all.

This is good feedback, I do accept deciding where to draw the line is hard.
I decided to go with blocking/non-blocking as the fine line.

> Things like that may be ok as an internal implementation, but even
> there it's questionable if it then means a big disconnect between what
> people actually use (the normal functional model) and the
> implementation.

A vendor tree implemented their *own* solution and were willing to maintain
it despite this likely making it hard to port stable fixes. That I think says
a lot for a need...

> The thing is, it's much better to just have functions that load the
> firmware data. Have them named that way ("load_firmware()"), and act
> that way ("just load the damn firmware file") instead of having odd
> descriptors that describe what is goign to be done and some state for
> it, and then get passed around.
> 
> Don't add this kind of crazy abstraction complexity.
> 
> If somebody wants to veryify a signature on a firmware file, they
> should *NOT* fill in a descriptor that says "check signature when
> loading". Thats' complete BS.
> 
> They should just do "load_firmware()" and then "check_signature()" or 
> whatever.

That's a fair suggestion for firmware signing! And I'll let AKASHI comment on
whether or not that would suffice for his requirements given he's now
addressing firmware signing.

There are still other requirements and features in the pipeline for which we
can consider parameters to parse for, rather than adding new API. Case in
point, do we want *one* API just to disable the firmware cache? Specially
knowing that another feature in the pipeline later would make use of this as a
requirement?

Or let us just consider the very simple *optional* async firmware. Do we add
*one* full new API call just for that?

  Luis

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Luis R. Rodriguez]

On Fri, Jun 23, 2017 at 04:09:29PM -0700, Linus Torvalds wrote:
> On Fri, Jun 23, 2017 at 3:43 PM, Luis R. Rodriguez  wrote:
> >
> > Ah, yes! Here is what I believe seems to be the *crux* issue of these patch
> > series and I'm happy we have finally landed on it. Yes, indeed the new API
> > proposed here provides more flexibility, and it does so by embracing a
> > "data driven" API Vs the traditional procedural APIs we have seen for
> > *the firmware API*.
> 
> This has been going on forever. Everybody hates your data-driven one.

Before you, the only person who had expressed disdain here was Greg.

> It's too indirect, it adds all those nasty "descriptors" of what to
> do, and it doesn't match what the current model does at all.

This is good feedback, I do accept deciding where to draw the line is hard.
I decided to go with blocking/non-blocking as the fine line.

> Things like that may be ok as an internal implementation, but even
> there it's questionable if it then means a big disconnect between what
> people actually use (the normal functional model) and the
> implementation.

A vendor tree implemented their *own* solution and were willing to maintain
it despite this likely making it hard to port stable fixes. That I think says
a lot for a need...

> The thing is, it's much better to just have functions that load the
> firmware data. Have them named that way ("load_firmware()"), and act
> that way ("just load the damn firmware file") instead of having odd
> descriptors that describe what is goign to be done and some state for
> it, and then get passed around.
> 
> Don't add this kind of crazy abstraction complexity.
> 
> If somebody wants to veryify a signature on a firmware file, they
> should *NOT* fill in a descriptor that says "check signature when
> loading". Thats' complete BS.
> 
> They should just do "load_firmware()" and then "check_signature()" or 
> whatever.

That's a fair suggestion for firmware signing! And I'll let AKASHI comment on
whether or not that would suffice for his requirements given he's now
addressing firmware signing.

There are still other requirements and features in the pipeline for which we
can consider parameters to parse for, rather than adding new API. Case in
point, do we want *one* API just to disable the firmware cache? Specially
knowing that another feature in the pipeline later would make use of this as a
requirement?

Or let us just consider the very simple *optional* async firmware. Do we add
*one* full new API call just for that?

  Luis

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Linus Torvalds]

On Fri, Jun 23, 2017 at 3:43 PM, Luis R. Rodriguez  wrote:
>
> Ah, yes! Here is what I believe seems to be the *crux* issue of these patch
> series and I'm happy we have finally landed on it. Yes, indeed the new API
> proposed here provides more flexibility, and it does so by embracing a
> "data driven" API Vs the traditional procedural APIs we have seen for
> *the firmware API*.

This has been going on forever. Everybody hates your data-driven one.
It's too indirect, it adds all those nasty "descriptors" of what to
do, and it doesn't match what the current model does at all.

Things like that may be ok as an internal implementation, but even
there it's questionable if it then means a big disconnect between what
people actually use (the normal functional model) and the
implementation.

The thing is, it's much better to just have functions that load the
firmware data. Have them named that way ("load_firmware()"), and act
that way ("just load the damn firmware file") instead of having odd
descriptors that describe what is goign to be done and some state for
it, and then get passed around.

Don't add this kind of crazy abstraction complexity.

If somebody wants to veryify a signature on a firmware file, they
should *NOT* fill in a descriptor that says "check signature when
loading". Thats' complete BS.

They should just do "load_firmware()" and then "check_signature()" or whatever.

Would such a "load firmware file, then check signature" take a few
lines (with error handling)? Yes.

But it is a *simple* interface. It doesn't have some stupid "struct
driver_data_params" that needs to be filled in with random details (or
has magic macros in a header file that fill in default values). It's
_straightforward_.

Linus

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Linus Torvalds]

On Fri, Jun 23, 2017 at 3:43 PM, Luis R. Rodriguez  wrote:
>
> Ah, yes! Here is what I believe seems to be the *crux* issue of these patch
> series and I'm happy we have finally landed on it. Yes, indeed the new API
> proposed here provides more flexibility, and it does so by embracing a
> "data driven" API Vs the traditional procedural APIs we have seen for
> *the firmware API*.

This has been going on forever. Everybody hates your data-driven one.
It's too indirect, it adds all those nasty "descriptors" of what to
do, and it doesn't match what the current model does at all.

Things like that may be ok as an internal implementation, but even
there it's questionable if it then means a big disconnect between what
people actually use (the normal functional model) and the
implementation.

The thing is, it's much better to just have functions that load the
firmware data. Have them named that way ("load_firmware()"), and act
that way ("just load the damn firmware file") instead of having odd
descriptors that describe what is goign to be done and some state for
it, and then get passed around.

Don't add this kind of crazy abstraction complexity.

If somebody wants to veryify a signature on a firmware file, they
should *NOT* fill in a descriptor that says "check signature when
loading". Thats' complete BS.

They should just do "load_firmware()" and then "check_signature()" or whatever.

Would such a "load firmware file, then check signature" take a few
lines (with error handling)? Yes.

But it is a *simple* interface. It doesn't have some stupid "struct
driver_data_params" that needs to be filled in with random details (or
has magic macros in a header file that fill in default values). It's
_straightforward_.

Linus

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Luis R. Rodriguez]

On Fri, Jun 23, 2017 at 11:59:36PM +0800, Greg KH wrote:
> On Mon, Jun 19, 2017 at 09:35:22PM +0200, Luis R. Rodriguez wrote:
> > You may argue that *one* upstream users is not sufficient to introduce a new
> > feature for, but I disagree given we have had new full *API* added for a new
> > feature on the firmware API even for drivers THAT ARE NOT UPSTREAM! For
> > instance request_firmware_into_buf() has no upstream users!!!
> 
> That's not acceptable at all, I'll send a patch after this to remove
> that.  We don't keep apis around with no in-kernel users, you know this.

I'm delighted to hear we can do away with the request_firmware_into_buf() crap.

> > Now, you might say that even though this is true that there many users of
> > out-of-tree drivers that need this. While true, if this is the bar we'd go
> > with, we can't then ignore the iwlwifi userbase, and the possible gains of
> > having a proper non-recursive use of the daisy chained requests.
> 
> Nope, I don't care about out-of-tree drivers as we have no idea what is
> going on there at all.  I've always had this position.

Beautiful. Music to my ears.

  Luis

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Luis R. Rodriguez]

On Fri, Jun 23, 2017 at 11:59:36PM +0800, Greg KH wrote:
> On Mon, Jun 19, 2017 at 09:35:22PM +0200, Luis R. Rodriguez wrote:
> > You may argue that *one* upstream users is not sufficient to introduce a new
> > feature for, but I disagree given we have had new full *API* added for a new
> > feature on the firmware API even for drivers THAT ARE NOT UPSTREAM! For
> > instance request_firmware_into_buf() has no upstream users!!!
> 
> That's not acceptable at all, I'll send a patch after this to remove
> that.  We don't keep apis around with no in-kernel users, you know this.

I'm delighted to hear we can do away with the request_firmware_into_buf() crap.

> > Now, you might say that even though this is true that there many users of
> > out-of-tree drivers that need this. While true, if this is the bar we'd go
> > with, we can't then ignore the iwlwifi userbase, and the possible gains of
> > having a proper non-recursive use of the daisy chained requests.
> 
> Nope, I don't care about out-of-tree drivers as we have no idea what is
> going on there at all.  I've always had this position.

Beautiful. Music to my ears.

  Luis

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Luis R. Rodriguez]

On Fri, Jun 23, 2017 at 11:51:23PM +0800, Greg KH wrote:
> On Mon, Jun 19, 2017 at 09:35:22PM +0200, Luis R. Rodriguez wrote:
> > > I agree, that's what I'm saying here.  I just do not see that happening
> > > with your patch set at all.  It's adding more code, a more complex way
> > > to interact with the subsystem, and not making driver writer lives any
> > > easier at all that I can see.
> > 
> > There are two things to consider:
> > 
> > a) The current design of the firmware API, and interfaces with exported 
> > symbols
> > 
> > The case for the driver data API was that we were being super sloppy with 
> > extensions,
> > to the point was making the internal code base very bug prone and full or 
> > redirect
> > conditionals with #ifdefery nightmware stuff.
> >
> > b) Features of the firmware API
> > 
> > These have to be evaluated on a case by case basis.
> 
> Wait, no, you didn't address my main complaint at all here.  You are
> adding complexity for no perceived gain at all with this patch set.
> 
> Now you might feel that this series gets you moving forward toward an
> end goal of reduced complexity and wonderfulness, but you know how
> kernel development works, you have to justify _all_ of your changes, not
> just some future end result that is not even presented here.

My point was that a) was already complex, so to say what I'm adding
to address a) is complex would be unfair, so rather the question should
be if its less complex, or if there are valid technical issues I'd like
to hear them.

> 
> 
> I, and others I know, have told you to work on simplifying your
> responses, and descriptions, of patches.  Take the extra time to make a
> shorter answer.  You will get better results, as I dread having to read
> and respond to them currently.

Sure, point taken!

> I know you have spent a lot of time and effort on this work, but as it
> stands, this crazy new interface (data-driven api vs. the traditional
> procedural apis we know and love in Linux), is not acceptable at all.

Ah, yes! Here is what I believe seems to be the *crux* issue of these patch
series and I'm happy we have finally landed on it. Yes, indeed the new API
proposed here provides more flexibility, and it does so by embracing a
"data driven" API Vs the traditional procedural APIs we have seen for
*the firmware API*. If by data-driven you mean using structs to drive the
requirements, instead of adding more API per new feature.

I would strongly disagree that we always prefer adding new functional APIs
loosely.  I think this should be reviewed on a case by case basis and it should
be up to the maintainer who has better visibility into the history of the code,
and what is coming. A quick git log grep found a recent commit example where we
take on a flexible API on other *random* places in Linux. Refer to for example
the change form bioset_create_nobvec() to bioset_create() and use flags in the
patch titled "blk: replace bioset_create_nobvec() with a flags arg to
bioset_create()", present on linux-next [0] followed by "blk: make the bioset
rescue_workqueue optional." [1] which also extends the flags and uses them.

To argue that we *still* need to keep doing a functional approach for the
firmware API and keep adding new routines for new features, seems insane to me
at this point -- if that is what you were suggesting...

Also, the reason *why* I think this discussion is important is that it also
implicates the amount of collateral evolutions needed per API. If you embrace
data-driven API (or flags, or structs for APIs) you should see less patches
due to collateral evolutions. In a way its my own resolution to mitigate
*unnecessary* collateral evolutions by proper architecture. Where that line is
drawn should be up to the designers of the API.

For system calls, for instance, I think its well accepted we *never* want to
make inflexible APIs. There is strong history for why that is the case. We
cannot compare system calls to exported symbols, at all, but we can learn a bit
from the flexibility efforts on them for exported symbols as well.  Its *real
news* to me that we *always* prefer a procedural preferences for APIs /
exported symbols.

[0] 
https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=011067b05668b05aae88e5a24cff0ca0a67ca0b0
[1] 
https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=47e0fb461fca1a68a566c82fcc006cc787312d8c

> It's also blocking real bug fixes and features that people want
> addressed, which isn't acceptable.

What? What bugs ? I have addressed *every single* stable issue in queue and
have sent patches for them and they do not depend in any way on any of this
series! In fact I've taken liberty to go to great lengths to ensure *stable*
proposals *get proper review* so we *do the right thing*. Case in point was the
recent -ERESTART crap which in the end we ended up moving towards preferring
adding new swait API for stable for it.

I have ZERO stable fixes 

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Luis R. Rodriguez]

On Fri, Jun 23, 2017 at 11:51:23PM +0800, Greg KH wrote:
> On Mon, Jun 19, 2017 at 09:35:22PM +0200, Luis R. Rodriguez wrote:
> > > I agree, that's what I'm saying here.  I just do not see that happening
> > > with your patch set at all.  It's adding more code, a more complex way
> > > to interact with the subsystem, and not making driver writer lives any
> > > easier at all that I can see.
> > 
> > There are two things to consider:
> > 
> > a) The current design of the firmware API, and interfaces with exported 
> > symbols
> > 
> > The case for the driver data API was that we were being super sloppy with 
> > extensions,
> > to the point was making the internal code base very bug prone and full or 
> > redirect
> > conditionals with #ifdefery nightmware stuff.
> >
> > b) Features of the firmware API
> > 
> > These have to be evaluated on a case by case basis.
> 
> Wait, no, you didn't address my main complaint at all here.  You are
> adding complexity for no perceived gain at all with this patch set.
> 
> Now you might feel that this series gets you moving forward toward an
> end goal of reduced complexity and wonderfulness, but you know how
> kernel development works, you have to justify _all_ of your changes, not
> just some future end result that is not even presented here.

My point was that a) was already complex, so to say what I'm adding
to address a) is complex would be unfair, so rather the question should
be if its less complex, or if there are valid technical issues I'd like
to hear them.

> 
> 
> I, and others I know, have told you to work on simplifying your
> responses, and descriptions, of patches.  Take the extra time to make a
> shorter answer.  You will get better results, as I dread having to read
> and respond to them currently.

Sure, point taken!

> I know you have spent a lot of time and effort on this work, but as it
> stands, this crazy new interface (data-driven api vs. the traditional
> procedural apis we know and love in Linux), is not acceptable at all.

Ah, yes! Here is what I believe seems to be the *crux* issue of these patch
series and I'm happy we have finally landed on it. Yes, indeed the new API
proposed here provides more flexibility, and it does so by embracing a
"data driven" API Vs the traditional procedural APIs we have seen for
*the firmware API*. If by data-driven you mean using structs to drive the
requirements, instead of adding more API per new feature.

I would strongly disagree that we always prefer adding new functional APIs
loosely.  I think this should be reviewed on a case by case basis and it should
be up to the maintainer who has better visibility into the history of the code,
and what is coming. A quick git log grep found a recent commit example where we
take on a flexible API on other *random* places in Linux. Refer to for example
the change form bioset_create_nobvec() to bioset_create() and use flags in the
patch titled "blk: replace bioset_create_nobvec() with a flags arg to
bioset_create()", present on linux-next [0] followed by "blk: make the bioset
rescue_workqueue optional." [1] which also extends the flags and uses them.

To argue that we *still* need to keep doing a functional approach for the
firmware API and keep adding new routines for new features, seems insane to me
at this point -- if that is what you were suggesting...

Also, the reason *why* I think this discussion is important is that it also
implicates the amount of collateral evolutions needed per API. If you embrace
data-driven API (or flags, or structs for APIs) you should see less patches
due to collateral evolutions. In a way its my own resolution to mitigate
*unnecessary* collateral evolutions by proper architecture. Where that line is
drawn should be up to the designers of the API.

For system calls, for instance, I think its well accepted we *never* want to
make inflexible APIs. There is strong history for why that is the case. We
cannot compare system calls to exported symbols, at all, but we can learn a bit
from the flexibility efforts on them for exported symbols as well.  Its *real
news* to me that we *always* prefer a procedural preferences for APIs /
exported symbols.

[0] 
https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=011067b05668b05aae88e5a24cff0ca0a67ca0b0
[1] 
https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=47e0fb461fca1a68a566c82fcc006cc787312d8c

> It's also blocking real bug fixes and features that people want
> addressed, which isn't acceptable.

What? What bugs ? I have addressed *every single* stable issue in queue and
have sent patches for them and they do not depend in any way on any of this
series! In fact I've taken liberty to go to great lengths to ensure *stable*
proposals *get proper review* so we *do the right thing*. Case in point was the
recent -ERESTART crap which in the end we ended up moving towards preferring
adding new swait API for stable for it.

I have ZERO stable fixes 

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Greg KH]

On Mon, Jun 19, 2017 at 09:35:22PM +0200, Luis R. Rodriguez wrote:
> > I agree, that's what I'm saying here.  I just do not see that happening
> > with your patch set at all.  It's adding more code, a more complex way
> > to interact with the subsystem, and not making driver writer lives any
> > easier at all that I can see.
> 
> There are two things to consider:
> 
> a) The current design of the firmware API, and interfaces with exported 
> symbols
> 
> The case for the driver data API was that we were being super sloppy with 
> extensions,
> to the point was making the internal code base very bug prone and full or 
> redirect
> conditionals with #ifdefery nightmware stuff.
>
> b) Features of the firmware API
> 
> These have to be evaluated on a case by case basis.

Wait, no, you didn't address my main complaint at all here.  You are
adding complexity for no perceived gain at all with this patch set.

Now you might feel that this series gets you moving forward toward an
end goal of reduced complexity and wonderfulness, but you know how
kernel development works, you have to justify _all_ of your changes, not
just some future end result that is not even presented here.



I, and others I know, have told you to work on simplifying your
responses, and descriptions, of patches.  Take the extra time to make a
shorter answer.  You will get better results, as I dread having to read
and respond to them currently.

I know you have spent a lot of time and effort on this work, but as it
stands, this crazy new interface (data-driven api vs. the traditional
procedural apis we know and love in Linux), is not acceptable at all.

It's also blocking real bug fixes and features that people want
addressed, which isn't acceptable.

Please take the time to step back, and see if you really want to spend
the effort into creating something that you can easily justify and break
down into acceptable patches.  If so, great, do it, but as it stands
today, that is not what you have done here, at all.

thanks,

greg k-h

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Greg KH]

On Mon, Jun 19, 2017 at 09:35:22PM +0200, Luis R. Rodriguez wrote:
> > I agree, that's what I'm saying here.  I just do not see that happening
> > with your patch set at all.  It's adding more code, a more complex way
> > to interact with the subsystem, and not making driver writer lives any
> > easier at all that I can see.
> 
> There are two things to consider:
> 
> a) The current design of the firmware API, and interfaces with exported 
> symbols
> 
> The case for the driver data API was that we were being super sloppy with 
> extensions,
> to the point was making the internal code base very bug prone and full or 
> redirect
> conditionals with #ifdefery nightmware stuff.
>
> b) Features of the firmware API
> 
> These have to be evaluated on a case by case basis.

Wait, no, you didn't address my main complaint at all here.  You are
adding complexity for no perceived gain at all with this patch set.

Now you might feel that this series gets you moving forward toward an
end goal of reduced complexity and wonderfulness, but you know how
kernel development works, you have to justify _all_ of your changes, not
just some future end result that is not even presented here.



I, and others I know, have told you to work on simplifying your
responses, and descriptions, of patches.  Take the extra time to make a
shorter answer.  You will get better results, as I dread having to read
and respond to them currently.

I know you have spent a lot of time and effort on this work, but as it
stands, this crazy new interface (data-driven api vs. the traditional
procedural apis we know and love in Linux), is not acceptable at all.

It's also blocking real bug fixes and features that people want
addressed, which isn't acceptable.

Please take the time to step back, and see if you really want to spend
the effort into creating something that you can easily justify and break
down into acceptable patches.  If so, great, do it, but as it stands
today, that is not what you have done here, at all.

thanks,

greg k-h

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Greg KH]

To respond to one issue in your wall-of-text response:

On Mon, Jun 19, 2017 at 09:35:22PM +0200, Luis R. Rodriguez wrote:
> You may argue that *one* upstream users is not sufficient to introduce a new
> feature for, but I disagree given we have had new full *API* added for a new
> feature on the firmware API even for drivers THAT ARE NOT UPSTREAM! For
> instance request_firmware_into_buf() has no upstream users!!!

That's not acceptable at all, I'll send a patch after this to remove
that.  We don't keep apis around with no in-kernel users, you know this.

> Now, you might say that even though this is true that there many users of
> out-of-tree drivers that need this. While true, if this is the bar we'd go
> with, we can't then ignore the iwlwifi userbase, and the possible gains of
> having a proper non-recursive use of the daisy chained requests.

Nope, I don't care about out-of-tree drivers as we have no idea what is
going on there at all.  I've always had this position.

Patch forthcoming.

greg k-h

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Greg KH]

To respond to one issue in your wall-of-text response:

On Mon, Jun 19, 2017 at 09:35:22PM +0200, Luis R. Rodriguez wrote:
> You may argue that *one* upstream users is not sufficient to introduce a new
> feature for, but I disagree given we have had new full *API* added for a new
> feature on the firmware API even for drivers THAT ARE NOT UPSTREAM! For
> instance request_firmware_into_buf() has no upstream users!!!

That's not acceptable at all, I'll send a patch after this to remove
that.  We don't keep apis around with no in-kernel users, you know this.

> Now, you might say that even though this is true that there many users of
> out-of-tree drivers that need this. While true, if this is the bar we'd go
> with, we can't then ignore the iwlwifi userbase, and the possible gains of
> having a proper non-recursive use of the daisy chained requests.

Nope, I don't care about out-of-tree drivers as we have no idea what is
going on there at all.  I've always had this position.

Patch forthcoming.

greg k-h

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Luis R. Rodriguez]

On Wed, Jun 21, 2017 at 09:49:35AM +0900, AKASHI Takahiro wrote:
> On Tue, Jun 20, 2017 at 07:22:19PM +0200, Luis R. Rodriguez wrote:
> > On Tue, Jun 20, 2017 at 09:27:45AM -0700, Vikram Mulukutla wrote:
> > > 
> > > perhaps a light
> > > internal rework inside firmware_class might be more suitable towards the
> > > extensibility goal while keeping driver API usage as simple as it is today
> > > (even if you hate my patch for various reasons)?
> > > 
> > > [1] - 
> > > https://source.codeaurora.org/quic/la/kernel/msm-3.18/commit/drivers/base/firmware_class.c?h=msm-3.18=7aa7efd3c150840369739893a84bd1d9f9774319
> > 
> > What you did is but one step I took, your changes make it easier to shuffle
> > data around internally. Its not sufficient to clean things up well enough, 
> > for
> > instance look at the "firmware behavior options" which are cleaned up in 
> > this
> > patch 1/5. That's been one pain on our side for a while, people 
> > understanding
> > when a flag applies or a feature, and making sure we document it all.
> > 
> > Then, one of the end goals is to provide extensibility, this is to allow 
> > users
> > to *pass* similar type of struct for either a sync or async call. Without 
> > this
> > the API remains unflexible and I predict we'll end up with the same 
> > situation
> > later anyway.
> > 
> > The approach I took uses an internal struct for passing required data for 
> > the
> > private internal API use. Then it also provides a public struct which can be
> > used to grow requirements to make only *new* API easily extensible.
> > 
> > So we need all three things to move forward.
> 
> Given the discussions here, it would be better to split your [1/5] and
> [2/5] into more smaller pieces, say,
>   * re-factor the old APIs with introducing private fw_desc

So patch 1/5 introduces 3 structs:

o struct driver_data_req_params  - used for user specified parameters
o struct driver_data_priv_params - used for internal use only
o struct driver_data_params - stiches both of the above together,
  only for internal use

I could certainly split the patch to introduce each separately.

>   * add new APIs with extra public arguments

This was split out already, patch 2 is the first patch introducing new API.

>   * extend new APIs per-feature
>   - sync/async callbacks

I suppose the base would be what we have today, only in new form. And sure,
I can add the features one by one...

>   - API version, and so on

Right.

> This way, you can illustrate how your approach evolves and it may
> mitigate people's concern about how complicated it is on the surface,
> allowing for discussing each of aspects of new APIs separately.

This makes sense. Greg, does this make sense to you? Or are you stone cold
against all this?

  Luis

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Luis R. Rodriguez]

On Wed, Jun 21, 2017 at 09:49:35AM +0900, AKASHI Takahiro wrote:
> On Tue, Jun 20, 2017 at 07:22:19PM +0200, Luis R. Rodriguez wrote:
> > On Tue, Jun 20, 2017 at 09:27:45AM -0700, Vikram Mulukutla wrote:
> > > 
> > > perhaps a light
> > > internal rework inside firmware_class might be more suitable towards the
> > > extensibility goal while keeping driver API usage as simple as it is today
> > > (even if you hate my patch for various reasons)?
> > > 
> > > [1] - 
> > > https://source.codeaurora.org/quic/la/kernel/msm-3.18/commit/drivers/base/firmware_class.c?h=msm-3.18=7aa7efd3c150840369739893a84bd1d9f9774319
> > 
> > What you did is but one step I took, your changes make it easier to shuffle
> > data around internally. Its not sufficient to clean things up well enough, 
> > for
> > instance look at the "firmware behavior options" which are cleaned up in 
> > this
> > patch 1/5. That's been one pain on our side for a while, people 
> > understanding
> > when a flag applies or a feature, and making sure we document it all.
> > 
> > Then, one of the end goals is to provide extensibility, this is to allow 
> > users
> > to *pass* similar type of struct for either a sync or async call. Without 
> > this
> > the API remains unflexible and I predict we'll end up with the same 
> > situation
> > later anyway.
> > 
> > The approach I took uses an internal struct for passing required data for 
> > the
> > private internal API use. Then it also provides a public struct which can be
> > used to grow requirements to make only *new* API easily extensible.
> > 
> > So we need all three things to move forward.
> 
> Given the discussions here, it would be better to split your [1/5] and
> [2/5] into more smaller pieces, say,
>   * re-factor the old APIs with introducing private fw_desc

So patch 1/5 introduces 3 structs:

o struct driver_data_req_params  - used for user specified parameters
o struct driver_data_priv_params - used for internal use only
o struct driver_data_params - stiches both of the above together,
  only for internal use

I could certainly split the patch to introduce each separately.

>   * add new APIs with extra public arguments

This was split out already, patch 2 is the first patch introducing new API.

>   * extend new APIs per-feature
>   - sync/async callbacks

I suppose the base would be what we have today, only in new form. And sure,
I can add the features one by one...

>   - API version, and so on

Right.

> This way, you can illustrate how your approach evolves and it may
> mitigate people's concern about how complicated it is on the surface,
> allowing for discussing each of aspects of new APIs separately.

This makes sense. Greg, does this make sense to you? Or are you stone cold
against all this?

  Luis

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[AKASHI Takahiro]

On Tue, Jun 20, 2017 at 07:22:19PM +0200, Luis R. Rodriguez wrote:
> On Tue, Jun 20, 2017 at 09:27:45AM -0700, Vikram Mulukutla wrote:
> > 
> > perhaps a light
> > internal rework inside firmware_class might be more suitable towards the
> > extensibility goal while keeping driver API usage as simple as it is today
> > (even if you hate my patch for various reasons)?
> > 
> > [1] - 
> > https://source.codeaurora.org/quic/la/kernel/msm-3.18/commit/drivers/base/firmware_class.c?h=msm-3.18=7aa7efd3c150840369739893a84bd1d9f9774319
> 
> What you did is but one step I took, your changes make it easier to shuffle
> data around internally. Its not sufficient to clean things up well enough, for
> instance look at the "firmware behavior options" which are cleaned up in this
> patch 1/5. That's been one pain on our side for a while, people understanding
> when a flag applies or a feature, and making sure we document it all.
> 
> Then, one of the end goals is to provide extensibility, this is to allow users
> to *pass* similar type of struct for either a sync or async call. Without this
> the API remains unflexible and I predict we'll end up with the same situation
> later anyway.
> 
> The approach I took uses an internal struct for passing required data for the
> private internal API use. Then it also provides a public struct which can be
> used to grow requirements to make only *new* API easily extensible.
> 
> So we need all three things to move forward.

Given the discussions here, it would be better to split your [1/5] and
[2/5] into more smaller pieces, say,
  * re-factor the old APIs with introducing private fw_desc
  * add new APIs with extra public arguments
  * extend new APIs per-feature
  - sync/async callbacks
  - API version, and so on

This way, you can illustrate how your approach evolves and it may
mitigate people's concern about how complicated it is on the surface,
allowing for discussing each of aspects of new APIs separately.

Thanks,
-Takahiro AKASHI

>   Luis

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[AKASHI Takahiro]

On Tue, Jun 20, 2017 at 07:22:19PM +0200, Luis R. Rodriguez wrote:
> On Tue, Jun 20, 2017 at 09:27:45AM -0700, Vikram Mulukutla wrote:
> > 
> > perhaps a light
> > internal rework inside firmware_class might be more suitable towards the
> > extensibility goal while keeping driver API usage as simple as it is today
> > (even if you hate my patch for various reasons)?
> > 
> > [1] - 
> > https://source.codeaurora.org/quic/la/kernel/msm-3.18/commit/drivers/base/firmware_class.c?h=msm-3.18=7aa7efd3c150840369739893a84bd1d9f9774319
> 
> What you did is but one step I took, your changes make it easier to shuffle
> data around internally. Its not sufficient to clean things up well enough, for
> instance look at the "firmware behavior options" which are cleaned up in this
> patch 1/5. That's been one pain on our side for a while, people understanding
> when a flag applies or a feature, and making sure we document it all.
> 
> Then, one of the end goals is to provide extensibility, this is to allow users
> to *pass* similar type of struct for either a sync or async call. Without this
> the API remains unflexible and I predict we'll end up with the same situation
> later anyway.
> 
> The approach I took uses an internal struct for passing required data for the
> private internal API use. Then it also provides a public struct which can be
> used to grow requirements to make only *new* API easily extensible.
> 
> So we need all three things to move forward.

Given the discussions here, it would be better to split your [1/5] and
[2/5] into more smaller pieces, say,
  * re-factor the old APIs with introducing private fw_desc
  * add new APIs with extra public arguments
  * extend new APIs per-feature
  - sync/async callbacks
  - API version, and so on

This way, you can illustrate how your approach evolves and it may
mitigate people's concern about how complicated it is on the surface,
allowing for discussing each of aspects of new APIs separately.

Thanks,
-Takahiro AKASHI

>   Luis

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Luis R. Rodriguez]

On Tue, Jun 20, 2017 at 09:27:45AM -0700, Vikram Mulukutla wrote:
> 
> Hi Greg, Luis,
> 
> On 2017-06-17 12:38, Greg KH wrote:
> > On Tue, Jun 13, 2017 at 09:40:11PM +0200, Luis R. Rodriguez wrote:
> > > On Tue, Jun 13, 2017 at 11:05:48AM +0200, Greg KH wrote:
> > > > On Mon, Jun 05, 2017 at 02:39:33PM -0700, Luis R. Rodriguez wrote:
> > > > > As the firmware API evolves we keep extending functions with more 
> > > > > arguments.
> > > > > Stop this nonsense by proving an extensible data structure which can 
> > > > > be used
> > > > > to represent both user parameters and private internal parameters.
> > > >
> > > > Let's take a simple C function interface and make it a more complex
> > > > data-driven interface that is impossible to understand and obviously
> > > > understand how it is to be used and works!
> > > 
> > > The firmware codebase was already complex!
> > 
> > Heh, I'm not arguing with you there :)
> > 
> > > What you have to ask yourself really is if this makes it *less
> > > complex* and
> > > helps *clean things up* in a much better way than it was before.
> > > Also does it
> > > allow us to *pave the way for new functionality easily*, without
> > > creating
> > > further mess?
> > 
> > I agree, that's what I'm saying here.  I just do not see that happening
> > with your patch set at all.  It's adding more code, a more complex way
> > to interact with the subsystem, and not making driver writer lives any
> > easier at all that I can see.
> > 
> > Again, the code is now bigger, does more, with not even any real benefit
> > for existing users.
> > 
> > > If not, what concrete alternatives do you suggest?
> > 
> > It's working, so leave it alone?  :)
> > 
> 
> So I wanted to note here that I had a similar internal discussion with
> Stephen Boyd when he first upstreamed the request_firmware_into_buf API.

Thanks for sharing!

> I actually did change things a bit to pass around a 'desc' structure with all
> the flags and parameters in our internal vendor tree [1].

I'll note the "desc" approach and name was what I originally used also on my
earlier incarnations of the driver data API (back then the "sysdata API").

> This is a sort of
> an ultra-lite version of what Luis is trying to do - extensibility - but does
> not change the API for driver owners.

What I propose does not change the API for existing drivers either. The changes
I propose allows the flexibility both internally and externally but only
externally for newer APIs and features.

> Existing APIs become wrappers around
> the new API. My primary reason then was the number of things being passed
> around between layers of functions inside firmware_class seemed a bit
> untenable.

Yup!! Same applies to the public API!

> Just like Greg, Stephen also brought up the argument about why the
> unnecessary complication to the API without any measurable benefit - this
> seemed a fair argument to me at that time. But here's my point - if Luis
> agrees that _this_ patchset is going slightly Mjolnir, 

One of the issues you'd face with your changes is you are essentially diverging
now with *similar* cleanup but its *not upstream*, so fixes may require manual
manipulation! The place to address what you need is not a private vendor tree
but *upstream* otherwise your tree will diverge and can make it hard for you to
merge stable fixes or cherry pick enhancements.

The fact that folks are willing to go the such lengths as to *merge* side
internal cleanups to internal APIs should say a lot of confirming the need for
my own work.

I stand by this work as needed, I have been the one doing the heavy lifting of
addressing fixes, documenting it and looking at a real sensible way to extend
it, as such I really do believe its needed. I'm tired of seeing side hacks and
people throwing gum at things.

> perhaps a light
> internal rework inside firmware_class might be more suitable towards the
> extensibility goal while keeping driver API usage as simple as it is today
> (even if you hate my patch for various reasons)?
> 
> [1] - 
> https://source.codeaurora.org/quic/la/kernel/msm-3.18/commit/drivers/base/firmware_class.c?h=msm-3.18=7aa7efd3c150840369739893a84bd1d9f9774319

What you did is but one step I took, your changes make it easier to shuffle
data around internally. Its not sufficient to clean things up well enough, for
instance look at the "firmware behavior options" which are cleaned up in this
patch 1/5. That's been one pain on our side for a while, people understanding
when a flag applies or a feature, and making sure we document it all.

Then, one of the end goals is to provide extensibility, this is to allow users
to *pass* similar type of struct for either a sync or async call. Without this
the API remains unflexible and I predict we'll end up with the same situation
later anyway.

The approach I took uses an internal struct for passing required data for the
private internal API use. Then it also provides a public struct which can be
used to 

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Luis R. Rodriguez]

On Tue, Jun 20, 2017 at 09:27:45AM -0700, Vikram Mulukutla wrote:
> 
> Hi Greg, Luis,
> 
> On 2017-06-17 12:38, Greg KH wrote:
> > On Tue, Jun 13, 2017 at 09:40:11PM +0200, Luis R. Rodriguez wrote:
> > > On Tue, Jun 13, 2017 at 11:05:48AM +0200, Greg KH wrote:
> > > > On Mon, Jun 05, 2017 at 02:39:33PM -0700, Luis R. Rodriguez wrote:
> > > > > As the firmware API evolves we keep extending functions with more 
> > > > > arguments.
> > > > > Stop this nonsense by proving an extensible data structure which can 
> > > > > be used
> > > > > to represent both user parameters and private internal parameters.
> > > >
> > > > Let's take a simple C function interface and make it a more complex
> > > > data-driven interface that is impossible to understand and obviously
> > > > understand how it is to be used and works!
> > > 
> > > The firmware codebase was already complex!
> > 
> > Heh, I'm not arguing with you there :)
> > 
> > > What you have to ask yourself really is if this makes it *less
> > > complex* and
> > > helps *clean things up* in a much better way than it was before.
> > > Also does it
> > > allow us to *pave the way for new functionality easily*, without
> > > creating
> > > further mess?
> > 
> > I agree, that's what I'm saying here.  I just do not see that happening
> > with your patch set at all.  It's adding more code, a more complex way
> > to interact with the subsystem, and not making driver writer lives any
> > easier at all that I can see.
> > 
> > Again, the code is now bigger, does more, with not even any real benefit
> > for existing users.
> > 
> > > If not, what concrete alternatives do you suggest?
> > 
> > It's working, so leave it alone?  :)
> > 
> 
> So I wanted to note here that I had a similar internal discussion with
> Stephen Boyd when he first upstreamed the request_firmware_into_buf API.

Thanks for sharing!

> I actually did change things a bit to pass around a 'desc' structure with all
> the flags and parameters in our internal vendor tree [1].

I'll note the "desc" approach and name was what I originally used also on my
earlier incarnations of the driver data API (back then the "sysdata API").

> This is a sort of
> an ultra-lite version of what Luis is trying to do - extensibility - but does
> not change the API for driver owners.

What I propose does not change the API for existing drivers either. The changes
I propose allows the flexibility both internally and externally but only
externally for newer APIs and features.

> Existing APIs become wrappers around
> the new API. My primary reason then was the number of things being passed
> around between layers of functions inside firmware_class seemed a bit
> untenable.

Yup!! Same applies to the public API!

> Just like Greg, Stephen also brought up the argument about why the
> unnecessary complication to the API without any measurable benefit - this
> seemed a fair argument to me at that time. But here's my point - if Luis
> agrees that _this_ patchset is going slightly Mjolnir, 

One of the issues you'd face with your changes is you are essentially diverging
now with *similar* cleanup but its *not upstream*, so fixes may require manual
manipulation! The place to address what you need is not a private vendor tree
but *upstream* otherwise your tree will diverge and can make it hard for you to
merge stable fixes or cherry pick enhancements.

The fact that folks are willing to go the such lengths as to *merge* side
internal cleanups to internal APIs should say a lot of confirming the need for
my own work.

I stand by this work as needed, I have been the one doing the heavy lifting of
addressing fixes, documenting it and looking at a real sensible way to extend
it, as such I really do believe its needed. I'm tired of seeing side hacks and
people throwing gum at things.

> perhaps a light
> internal rework inside firmware_class might be more suitable towards the
> extensibility goal while keeping driver API usage as simple as it is today
> (even if you hate my patch for various reasons)?
> 
> [1] - 
> https://source.codeaurora.org/quic/la/kernel/msm-3.18/commit/drivers/base/firmware_class.c?h=msm-3.18=7aa7efd3c150840369739893a84bd1d9f9774319

What you did is but one step I took, your changes make it easier to shuffle
data around internally. Its not sufficient to clean things up well enough, for
instance look at the "firmware behavior options" which are cleaned up in this
patch 1/5. That's been one pain on our side for a while, people understanding
when a flag applies or a feature, and making sure we document it all.

Then, one of the end goals is to provide extensibility, this is to allow users
to *pass* similar type of struct for either a sync or async call. Without this
the API remains unflexible and I predict we'll end up with the same situation
later anyway.

The approach I took uses an internal struct for passing required data for the
private internal API use. Then it also provides a public struct which can be
used to 

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Vikram Mulukutla]

Hi Greg, Luis,

On 2017-06-17 12:38, Greg KH wrote:

On Tue, Jun 13, 2017 at 09:40:11PM +0200, Luis R. Rodriguez wrote:

On Tue, Jun 13, 2017 at 11:05:48AM +0200, Greg KH wrote:
> On Mon, Jun 05, 2017 at 02:39:33PM -0700, Luis R. Rodriguez wrote:
> > As the firmware API evolves we keep extending functions with more arguments.
> > Stop this nonsense by proving an extensible data structure which can be used
> > to represent both user parameters and private internal parameters.
>
> Let's take a simple C function interface and make it a more complex
> data-driven interface that is impossible to understand and obviously
> understand how it is to be used and works!

The firmware codebase was already complex!


Heh, I'm not arguing with you there :)

What you have to ask yourself really is if this makes it *less 
complex* and
helps *clean things up* in a much better way than it was before. Also 
does it
allow us to *pave the way for new functionality easily*, without 
creating

further mess?


I agree, that's what I'm saying here.  I just do not see that happening
with your patch set at all.  It's adding more code, a more complex way
to interact with the subsystem, and not making driver writer lives any
easier at all that I can see.

Again, the code is now bigger, does more, with not even any real 
benefit

for existing users.


If not, what concrete alternatives do you suggest?


It's working, so leave it alone?  :)



So I wanted to note here that I had a similar internal discussion with 
Stephen
Boyd when he first upstreamed the request_firmware_into_buf API. I 
actually did

change things a bit to pass around a 'desc' structure with all the flags
and parameters in our internal vendor tree [1]. This is a sort of an 
ultra-lite
version of what Luis is trying to do - extensibility - but does not 
change the API
for driver owners. Existing APIs become wrappers around the new API. My 
primary
reason then was the number of things being passed around between layers 
of functions

inside firmware_class seemed a bit untenable.

Just like Greg, Stephen also brought up the argument about why the
unnecessary complication to the API without any measurable benefit - 
this seemed
a fair argument to me at that time. But here's my point - if Luis agrees 
that _this_
patchset is going slightly Mjolnir, perhaps a light internal rework 
inside
firmware_class might be more suitable towards the extensibility goal 
while keeping
driver API usage as simple as it is today (even if you hate my patch for 
various

reasons)?

Thanks,
Vikram

[1] - 
https://source.codeaurora.org/quic/la/kernel/msm-3.18/commit/drivers/base/firmware_class.c?h=msm-3.18=7aa7efd3c150840369739893a84bd1d9f9774319

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Vikram Mulukutla]

Hi Greg, Luis,

On 2017-06-17 12:38, Greg KH wrote:

On Tue, Jun 13, 2017 at 09:40:11PM +0200, Luis R. Rodriguez wrote:

On Tue, Jun 13, 2017 at 11:05:48AM +0200, Greg KH wrote:
> On Mon, Jun 05, 2017 at 02:39:33PM -0700, Luis R. Rodriguez wrote:
> > As the firmware API evolves we keep extending functions with more arguments.
> > Stop this nonsense by proving an extensible data structure which can be used
> > to represent both user parameters and private internal parameters.
>
> Let's take a simple C function interface and make it a more complex
> data-driven interface that is impossible to understand and obviously
> understand how it is to be used and works!

The firmware codebase was already complex!


Heh, I'm not arguing with you there :)

What you have to ask yourself really is if this makes it *less 
complex* and
helps *clean things up* in a much better way than it was before. Also 
does it
allow us to *pave the way for new functionality easily*, without 
creating

further mess?


I agree, that's what I'm saying here.  I just do not see that happening
with your patch set at all.  It's adding more code, a more complex way
to interact with the subsystem, and not making driver writer lives any
easier at all that I can see.

Again, the code is now bigger, does more, with not even any real 
benefit

for existing users.


If not, what concrete alternatives do you suggest?


It's working, so leave it alone?  :)



So I wanted to note here that I had a similar internal discussion with 
Stephen
Boyd when he first upstreamed the request_firmware_into_buf API. I 
actually did

change things a bit to pass around a 'desc' structure with all the flags
and parameters in our internal vendor tree [1]. This is a sort of an 
ultra-lite
version of what Luis is trying to do - extensibility - but does not 
change the API
for driver owners. Existing APIs become wrappers around the new API. My 
primary
reason then was the number of things being passed around between layers 
of functions

inside firmware_class seemed a bit untenable.

Just like Greg, Stephen also brought up the argument about why the
unnecessary complication to the API without any measurable benefit - 
this seemed
a fair argument to me at that time. But here's my point - if Luis agrees 
that _this_
patchset is going slightly Mjolnir, perhaps a light internal rework 
inside
firmware_class might be more suitable towards the extensibility goal 
while keeping
driver API usage as simple as it is today (even if you hate my patch for 
various

reasons)?

Thanks,
Vikram

[1] - 
https://source.codeaurora.org/quic/la/kernel/msm-3.18/commit/drivers/base/firmware_class.c?h=msm-3.18=7aa7efd3c150840369739893a84bd1d9f9774319

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Li, Yi]

On 6/19/2017 8:48 PM, AKASHI Takahiro wrote:

On Mon, Jun 19, 2017 at 05:51:08PM -0500, Li, Yi wrote:

Hi Greg,

On 6/17/2017 2:38 PM, Greg KH wrote:

On Tue, Jun 13, 2017 at 09:40:11PM +0200, Luis R. Rodriguez wrote:

On Tue, Jun 13, 2017 at 11:05:48AM +0200, Greg KH wrote:

On Mon, Jun 05, 2017 at 02:39:33PM -0700, Luis R. Rodriguez wrote:



What you have to ask yourself really is if this makes it *less complex* and
helps *clean things up* in a much better way than it was before. Also does it
allow us to *pave the way for new functionality easily*, without creating
further mess?


I agree, that's what I'm saying here.  I just do not see that happening
with your patch set at all.  It's adding more code, a more complex way
to interact with the subsystem, and not making driver writer lives any
easier at all that I can see.

Again, the code is now bigger, does more, with not even any real benefit
for existing users.


I am still new to the upstreaming world, pardon me if my understanding is
naive. :) My take with Luis's driver data API is that it adds a wrapper on
top of the old request_firmware APIs, so the new features can be
added/disabled by the parameters structures instead of adding/changing API
functions. Agree that there is not much new for existing users. It adds more
codes (not necessary more complex) but create a consistent way for extension
IMO.


Most of code of my feature, firmware signing, is implemented in common
place between old and new APIs, while only new API has a parameter,
DRIVER_DATA_REQ_NO_SIG_CHECK, which allow users to enable/disable
this feature per-driver-datum. Simple enough.


I meant to say more code does NOT necessary equal to more complex, sorry 
for the confusion.




So what matters is adding yet another variant of request_firmware_xx()
vs. adding a mere parameter?


Agree, I also prefer the parameter approach.



Thanks,
-Takahiro AKASHI


Below are 3 examples I tried to add streaming support to load large firmware
files.
Adding streaming with driver data API:
https://patchwork.kernel.org/patch/9738503 . This patch series depends on
non-cache patch series https://patchwork.kernel.org/patch/9793825 , which is
bigger than it should be since it added some codes to test firmware caching.
and pre-allocate buffer patch series
https://patchwork.kernel.org/patch/9738487/

By comparison, here is my old streaming RFC with original firmware class:
https://lkml.org/lkml/2017/3/9/872
Do you think this is the better way?

Thanks,
Yi

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Li, Yi]

On 6/19/2017 8:48 PM, AKASHI Takahiro wrote:

On Mon, Jun 19, 2017 at 05:51:08PM -0500, Li, Yi wrote:

Hi Greg,

On 6/17/2017 2:38 PM, Greg KH wrote:

On Tue, Jun 13, 2017 at 09:40:11PM +0200, Luis R. Rodriguez wrote:

On Tue, Jun 13, 2017 at 11:05:48AM +0200, Greg KH wrote:

On Mon, Jun 05, 2017 at 02:39:33PM -0700, Luis R. Rodriguez wrote:



What you have to ask yourself really is if this makes it *less complex* and
helps *clean things up* in a much better way than it was before. Also does it
allow us to *pave the way for new functionality easily*, without creating
further mess?


I agree, that's what I'm saying here.  I just do not see that happening
with your patch set at all.  It's adding more code, a more complex way
to interact with the subsystem, and not making driver writer lives any
easier at all that I can see.

Again, the code is now bigger, does more, with not even any real benefit
for existing users.


I am still new to the upstreaming world, pardon me if my understanding is
naive. :) My take with Luis's driver data API is that it adds a wrapper on
top of the old request_firmware APIs, so the new features can be
added/disabled by the parameters structures instead of adding/changing API
functions. Agree that there is not much new for existing users. It adds more
codes (not necessary more complex) but create a consistent way for extension
IMO.


Most of code of my feature, firmware signing, is implemented in common
place between old and new APIs, while only new API has a parameter,
DRIVER_DATA_REQ_NO_SIG_CHECK, which allow users to enable/disable
this feature per-driver-datum. Simple enough.


I meant to say more code does NOT necessary equal to more complex, sorry 
for the confusion.




So what matters is adding yet another variant of request_firmware_xx()
vs. adding a mere parameter?


Agree, I also prefer the parameter approach.



Thanks,
-Takahiro AKASHI


Below are 3 examples I tried to add streaming support to load large firmware
files.
Adding streaming with driver data API:
https://patchwork.kernel.org/patch/9738503 . This patch series depends on
non-cache patch series https://patchwork.kernel.org/patch/9793825 , which is
bigger than it should be since it added some codes to test firmware caching.
and pre-allocate buffer patch series
https://patchwork.kernel.org/patch/9738487/

By comparison, here is my old streaming RFC with original firmware class:
https://lkml.org/lkml/2017/3/9/872
Do you think this is the better way?

Thanks,
Yi

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[AKASHI Takahiro]

On Mon, Jun 19, 2017 at 05:51:08PM -0500, Li, Yi wrote:
> Hi Greg,
> 
> On 6/17/2017 2:38 PM, Greg KH wrote:
> >On Tue, Jun 13, 2017 at 09:40:11PM +0200, Luis R. Rodriguez wrote:
> >>On Tue, Jun 13, 2017 at 11:05:48AM +0200, Greg KH wrote:
> >>>On Mon, Jun 05, 2017 at 02:39:33PM -0700, Luis R. Rodriguez wrote:
> >
> >>What you have to ask yourself really is if this makes it *less complex* and
> >>helps *clean things up* in a much better way than it was before. Also does 
> >>it
> >>allow us to *pave the way for new functionality easily*, without creating
> >>further mess?
> >
> >I agree, that's what I'm saying here.  I just do not see that happening
> >with your patch set at all.  It's adding more code, a more complex way
> >to interact with the subsystem, and not making driver writer lives any
> >easier at all that I can see.
> >
> >Again, the code is now bigger, does more, with not even any real benefit
> >for existing users.
> 
> I am still new to the upstreaming world, pardon me if my understanding is
> naive. :) My take with Luis's driver data API is that it adds a wrapper on
> top of the old request_firmware APIs, so the new features can be
> added/disabled by the parameters structures instead of adding/changing API
> functions. Agree that there is not much new for existing users. It adds more
> codes (not necessary more complex) but create a consistent way for extension
> IMO.

Most of code of my feature, firmware signing, is implemented in common
place between old and new APIs, while only new API has a parameter,
DRIVER_DATA_REQ_NO_SIG_CHECK, which allow users to enable/disable
this feature per-driver-datum. Simple enough.

So what matters is adding yet another variant of request_firmware_xx()
vs. adding a mere parameter?

Thanks,
-Takahiro AKASHI

> Below are 3 examples I tried to add streaming support to load large firmware
> files.
> Adding streaming with driver data API:
> https://patchwork.kernel.org/patch/9738503 . This patch series depends on
> non-cache patch series https://patchwork.kernel.org/patch/9793825 , which is
> bigger than it should be since it added some codes to test firmware caching.
> and pre-allocate buffer patch series
> https://patchwork.kernel.org/patch/9738487/
> 
> By comparison, here is my old streaming RFC with original firmware class:
> https://lkml.org/lkml/2017/3/9/872
> Do you think this is the better way?
> 
> Thanks,
> Yi

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[AKASHI Takahiro]

On Mon, Jun 19, 2017 at 05:51:08PM -0500, Li, Yi wrote:
> Hi Greg,
> 
> On 6/17/2017 2:38 PM, Greg KH wrote:
> >On Tue, Jun 13, 2017 at 09:40:11PM +0200, Luis R. Rodriguez wrote:
> >>On Tue, Jun 13, 2017 at 11:05:48AM +0200, Greg KH wrote:
> >>>On Mon, Jun 05, 2017 at 02:39:33PM -0700, Luis R. Rodriguez wrote:
> >
> >>What you have to ask yourself really is if this makes it *less complex* and
> >>helps *clean things up* in a much better way than it was before. Also does 
> >>it
> >>allow us to *pave the way for new functionality easily*, without creating
> >>further mess?
> >
> >I agree, that's what I'm saying here.  I just do not see that happening
> >with your patch set at all.  It's adding more code, a more complex way
> >to interact with the subsystem, and not making driver writer lives any
> >easier at all that I can see.
> >
> >Again, the code is now bigger, does more, with not even any real benefit
> >for existing users.
> 
> I am still new to the upstreaming world, pardon me if my understanding is
> naive. :) My take with Luis's driver data API is that it adds a wrapper on
> top of the old request_firmware APIs, so the new features can be
> added/disabled by the parameters structures instead of adding/changing API
> functions. Agree that there is not much new for existing users. It adds more
> codes (not necessary more complex) but create a consistent way for extension
> IMO.

Most of code of my feature, firmware signing, is implemented in common
place between old and new APIs, while only new API has a parameter,
DRIVER_DATA_REQ_NO_SIG_CHECK, which allow users to enable/disable
this feature per-driver-datum. Simple enough.

So what matters is adding yet another variant of request_firmware_xx()
vs. adding a mere parameter?

Thanks,
-Takahiro AKASHI

> Below are 3 examples I tried to add streaming support to load large firmware
> files.
> Adding streaming with driver data API:
> https://patchwork.kernel.org/patch/9738503 . This patch series depends on
> non-cache patch series https://patchwork.kernel.org/patch/9793825 , which is
> bigger than it should be since it added some codes to test firmware caching.
> and pre-allocate buffer patch series
> https://patchwork.kernel.org/patch/9738487/
> 
> By comparison, here is my old streaming RFC with original firmware class:
> https://lkml.org/lkml/2017/3/9/872
> Do you think this is the better way?
> 
> Thanks,
> Yi

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[AKASHI Takahiro]

On Mon, Jun 19, 2017 at 09:41:07PM +0200, Luis R. Rodriguez wrote:
> On Mon, Jun 19, 2017 at 09:33:16AM +0200, Johannes Berg wrote:
> > On Sat, 2017-06-17 at 21:38 +0200, Greg KH wrote:
> > 
> > > But we don't accept kernel patches for some mythical future option
> > > that might be happening some time in the future.  Heck, I'm still not
> > > convinced that firmware signing isn't anything more than just some
> > > snakeoil in the first place!
> > 
> > I for one really want the "firmware" signing, because I want to load
> > the regulatory database through this API, and 
> 
> This was my original goal as well... and it was also one of the reasons why
> the API name change would be much better reflective of future possible uses.
> 
> > But honestly, I've been waiting for years for that now and started
> > looking at what it would take to hand-implement that on top of the
> > existing firmware API. Probably not all that much.
> 
> I had proposed changes to do just this long ago, without any new *API*, so 
> we'd
> support firmware signing just as we do with module signing. Simple!
> 
> It was during these discussions that we realized we actually *wanted* to have
> the option to always specify requests with specific signing requirements from
> the start, as such a flexible API became a prerequisite and so I prioritized
> that work first.
> 
> Lets not ignore previous work and prior discussions then, the last effort on 
> this
> front was by AKASHI, and it'd be greatly appreciated if the topic of firmware
> signing was specifically addressed on that thread there [0].

+1
I always appreciate any comments from those who are for and against
my patch (or firmware signing in general) as well.

-Takahiro AKASHI


> [0] https://lkml.kernel.org/r/20170526030609.1414-1-takahiro.aka...@linaro.org
> 
>  Luis

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[AKASHI Takahiro]

On Mon, Jun 19, 2017 at 09:41:07PM +0200, Luis R. Rodriguez wrote:
> On Mon, Jun 19, 2017 at 09:33:16AM +0200, Johannes Berg wrote:
> > On Sat, 2017-06-17 at 21:38 +0200, Greg KH wrote:
> > 
> > > But we don't accept kernel patches for some mythical future option
> > > that might be happening some time in the future.  Heck, I'm still not
> > > convinced that firmware signing isn't anything more than just some
> > > snakeoil in the first place!
> > 
> > I for one really want the "firmware" signing, because I want to load
> > the regulatory database through this API, and 
> 
> This was my original goal as well... and it was also one of the reasons why
> the API name change would be much better reflective of future possible uses.
> 
> > But honestly, I've been waiting for years for that now and started
> > looking at what it would take to hand-implement that on top of the
> > existing firmware API. Probably not all that much.
> 
> I had proposed changes to do just this long ago, without any new *API*, so 
> we'd
> support firmware signing just as we do with module signing. Simple!
> 
> It was during these discussions that we realized we actually *wanted* to have
> the option to always specify requests with specific signing requirements from
> the start, as such a flexible API became a prerequisite and so I prioritized
> that work first.
> 
> Lets not ignore previous work and prior discussions then, the last effort on 
> this
> front was by AKASHI, and it'd be greatly appreciated if the topic of firmware
> signing was specifically addressed on that thread there [0].

+1
I always appreciate any comments from those who are for and against
my patch (or firmware signing in general) as well.

-Takahiro AKASHI


> [0] https://lkml.kernel.org/r/20170526030609.1414-1-takahiro.aka...@linaro.org
> 
>  Luis

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Li, Yi]

Hi Greg,

On 6/17/2017 2:38 PM, Greg KH wrote:

On Tue, Jun 13, 2017 at 09:40:11PM +0200, Luis R. Rodriguez wrote:

On Tue, Jun 13, 2017 at 11:05:48AM +0200, Greg KH wrote:

On Mon, Jun 05, 2017 at 02:39:33PM -0700, Luis R. Rodriguez wrote:

As the firmware API evolves we keep extending functions with more arguments.
Stop this nonsense by proving an extensible data structure which can be used
to represent both user parameters and private internal parameters.


Let's take a simple C function interface and make it a more complex
data-driven interface that is impossible to understand and obviously
understand how it is to be used and works!


The firmware codebase was already complex!


Heh, I'm not arguing with you there :)


What you have to ask yourself really is if this makes it *less complex* and
helps *clean things up* in a much better way than it was before. Also does it
allow us to *pave the way for new functionality easily*, without creating
further mess?


I agree, that's what I'm saying here.  I just do not see that happening
with your patch set at all.  It's adding more code, a more complex way
to interact with the subsystem, and not making driver writer lives any
easier at all that I can see.

Again, the code is now bigger, does more, with not even any real benefit
for existing users.


I am still new to the upstreaming world, pardon me if my understanding 
is naive. :) My take with Luis's driver data API is that it adds a 
wrapper on top of the old request_firmware APIs, so the new features can 
be added/disabled by the parameters structures instead of 
adding/changing API functions. Agree that there is not much new for 
existing users. It adds more codes (not necessary more complex) but 
create a consistent way for extension IMO.


Below are 3 examples I tried to add streaming support to load large 
firmware files.
Adding streaming with driver data API: 
https://patchwork.kernel.org/patch/9738503 . This patch series depends on
non-cache patch series https://patchwork.kernel.org/patch/9793825 , 
which is bigger than it should be since it added some codes to test 
firmware caching.
and pre-allocate buffer patch series 
https://patchwork.kernel.org/patch/9738487/


By comparison, here is my old streaming RFC with original firmware 
class: https://lkml.org/lkml/2017/3/9/872

Do you think this is the better way?

Thanks,
Yi




If not, what concrete alternatives do you suggest?


It's working, so leave it alone?  :)


:(

Seriously, why?  Why are we extending any of this at all?


Addressing easy extensibility was a prerequisite of considering firmware signing
support. Its really the *only* reason I started reviewing the firmware API, to 
the
point I started helping fix quite a bit of bugs and now just became the 
maintainer.

So my original firmware signing effort, now driven by AKASHI Takahiro, was one
of the original motivations here!


But we don't accept kernel patches for some mythical future option that
might be happening some time in the future.  Heck, I'm still not
convinced that firmware signing isn't anything more than just some
snakeoil in the first place!

So while you mention lots of times that all sorts of wonderful things
can now possibly be built on top of the new code, I have yet to see it
(meaning you didn't include it in the patch series.)

To get me to take these changes, you have to show a real need and user
of the code.  Without that it just strongly looks like you are having
fun making a more complex api for no reason that we are then going to be
stuck with maintaining.

So clean away, and fix up, but remember, you have to be able to justify
each change as being needed.  And so far, I'm not sold on this at all,
sorry.

thanks,

greg k-h

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Li, Yi]

Hi Greg,

On 6/17/2017 2:38 PM, Greg KH wrote:

On Tue, Jun 13, 2017 at 09:40:11PM +0200, Luis R. Rodriguez wrote:

On Tue, Jun 13, 2017 at 11:05:48AM +0200, Greg KH wrote:

On Mon, Jun 05, 2017 at 02:39:33PM -0700, Luis R. Rodriguez wrote:

As the firmware API evolves we keep extending functions with more arguments.
Stop this nonsense by proving an extensible data structure which can be used
to represent both user parameters and private internal parameters.


Let's take a simple C function interface and make it a more complex
data-driven interface that is impossible to understand and obviously
understand how it is to be used and works!


The firmware codebase was already complex!


Heh, I'm not arguing with you there :)


What you have to ask yourself really is if this makes it *less complex* and
helps *clean things up* in a much better way than it was before. Also does it
allow us to *pave the way for new functionality easily*, without creating
further mess?


I agree, that's what I'm saying here.  I just do not see that happening
with your patch set at all.  It's adding more code, a more complex way
to interact with the subsystem, and not making driver writer lives any
easier at all that I can see.

Again, the code is now bigger, does more, with not even any real benefit
for existing users.


I am still new to the upstreaming world, pardon me if my understanding 
is naive. :) My take with Luis's driver data API is that it adds a 
wrapper on top of the old request_firmware APIs, so the new features can 
be added/disabled by the parameters structures instead of 
adding/changing API functions. Agree that there is not much new for 
existing users. It adds more codes (not necessary more complex) but 
create a consistent way for extension IMO.


Below are 3 examples I tried to add streaming support to load large 
firmware files.
Adding streaming with driver data API: 
https://patchwork.kernel.org/patch/9738503 . This patch series depends on
non-cache patch series https://patchwork.kernel.org/patch/9793825 , 
which is bigger than it should be since it added some codes to test 
firmware caching.
and pre-allocate buffer patch series 
https://patchwork.kernel.org/patch/9738487/


By comparison, here is my old streaming RFC with original firmware 
class: https://lkml.org/lkml/2017/3/9/872

Do you think this is the better way?

Thanks,
Yi




If not, what concrete alternatives do you suggest?


It's working, so leave it alone?  :)


:(

Seriously, why?  Why are we extending any of this at all?


Addressing easy extensibility was a prerequisite of considering firmware signing
support. Its really the *only* reason I started reviewing the firmware API, to 
the
point I started helping fix quite a bit of bugs and now just became the 
maintainer.

So my original firmware signing effort, now driven by AKASHI Takahiro, was one
of the original motivations here!


But we don't accept kernel patches for some mythical future option that
might be happening some time in the future.  Heck, I'm still not
convinced that firmware signing isn't anything more than just some
snakeoil in the first place!

So while you mention lots of times that all sorts of wonderful things
can now possibly be built on top of the new code, I have yet to see it
(meaning you didn't include it in the patch series.)

To get me to take these changes, you have to show a real need and user
of the code.  Without that it just strongly looks like you are having
fun making a more complex api for no reason that we are then going to be
stuck with maintaining.

So clean away, and fix up, but remember, you have to be able to justify
each change as being needed.  And so far, I'm not sold on this at all,
sorry.

thanks,

greg k-h

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Luis R. Rodriguez]

On Mon, Jun 19, 2017 at 09:33:16AM +0200, Johannes Berg wrote:
> On Sat, 2017-06-17 at 21:38 +0200, Greg KH wrote:
> 
> > But we don't accept kernel patches for some mythical future option
> > that might be happening some time in the future.  Heck, I'm still not
> > convinced that firmware signing isn't anything more than just some
> > snakeoil in the first place!
> 
> I for one really want the "firmware" signing, because I want to load
> the regulatory database through this API, and 

This was my original goal as well... and it was also one of the reasons why
the API name change would be much better reflective of future possible uses.

> But honestly, I've been waiting for years for that now and started
> looking at what it would take to hand-implement that on top of the
> existing firmware API. Probably not all that much.

I had proposed changes to do just this long ago, without any new *API*, so we'd
support firmware signing just as we do with module signing. Simple!

It was during these discussions that we realized we actually *wanted* to have
the option to always specify requests with specific signing requirements from
the start, as such a flexible API became a prerequisite and so I prioritized
that work first.

Lets not ignore previous work and prior discussions then, the last effort on 
this
front was by AKASHI, and it'd be greatly appreciated if the topic of firmware
signing was specifically addressed on that thread there [0].

[0] https://lkml.kernel.org/r/20170526030609.1414-1-takahiro.aka...@linaro.org

 Luis

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Luis R. Rodriguez]

On Mon, Jun 19, 2017 at 09:33:16AM +0200, Johannes Berg wrote:
> On Sat, 2017-06-17 at 21:38 +0200, Greg KH wrote:
> 
> > But we don't accept kernel patches for some mythical future option
> > that might be happening some time in the future.  Heck, I'm still not
> > convinced that firmware signing isn't anything more than just some
> > snakeoil in the first place!
> 
> I for one really want the "firmware" signing, because I want to load
> the regulatory database through this API, and 

This was my original goal as well... and it was also one of the reasons why
the API name change would be much better reflective of future possible uses.

> But honestly, I've been waiting for years for that now and started
> looking at what it would take to hand-implement that on top of the
> existing firmware API. Probably not all that much.

I had proposed changes to do just this long ago, without any new *API*, so we'd
support firmware signing just as we do with module signing. Simple!

It was during these discussions that we realized we actually *wanted* to have
the option to always specify requests with specific signing requirements from
the start, as such a flexible API became a prerequisite and so I prioritized
that work first.

Lets not ignore previous work and prior discussions then, the last effort on 
this
front was by AKASHI, and it'd be greatly appreciated if the topic of firmware
signing was specifically addressed on that thread there [0].

[0] https://lkml.kernel.org/r/20170526030609.1414-1-takahiro.aka...@linaro.org

 Luis

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Luis R. Rodriguez]

On Sat, Jun 17, 2017 at 09:38:15PM +0200, Greg KH wrote:
> On Tue, Jun 13, 2017 at 09:40:11PM +0200, Luis R. Rodriguez wrote:
> > On Tue, Jun 13, 2017 at 11:05:48AM +0200, Greg KH wrote:
> > > On Mon, Jun 05, 2017 at 02:39:33PM -0700, Luis R. Rodriguez wrote:
> > > > As the firmware API evolves we keep extending functions with more 
> > > > arguments.
> > > > Stop this nonsense by proving an extensible data structure which can be 
> > > > used
> > > > to represent both user parameters and private internal parameters.
> > > 
> > > Let's take a simple C function interface and make it a more complex
> > > data-driven interface that is impossible to understand and obviously
> > > understand how it is to be used and works!
> > 
> > The firmware codebase was already complex!
> 
> Heh, I'm not arguing with you there :)

Great!

> > What you have to ask yourself really is if this makes it *less complex* and
> > helps *clean things up* in a much better way than it was before. Also does 
> > it
> > allow us to *pave the way for new functionality easily*, without creating
> > further mess?
> 
> I agree, that's what I'm saying here.  I just do not see that happening
> with your patch set at all.  It's adding more code, a more complex way
> to interact with the subsystem, and not making driver writer lives any
> easier at all that I can see.

There are two things to consider:

a) The current design of the firmware API, and interfaces with exported symbols

The case for the driver data API was that we were being super sloppy with 
extensions,
to the point was making the internal code base very bug prone and full or 
redirect
conditionals with #ifdefery nightmware stuff.
   
b) Features of the firmware API

These have to be evaluated on a case by case basis.

> Again, the code is now bigger, does more, with not even any real benefit
> for existing users.

Obviously I disagree strongly, in light of the history of the code. Not only
should the existing code be compared but also how it has evolved and we should
evaluate whether or not its evolution can be dealt with more appropriately.

> > If not, what concrete alternatives do you suggest?
> 
> It's working, so leave it alone?  :)

As the maintainer of the firmware API I **totally** disagree!!

First the firmware API has been evolving as pieces of gum thrown at it. A
proper design of the API in consideration of extensions is in order.  Likewise
goes for testing and documentation. Second, it cannot be said with any serious
tone that the current design has worked well.  It is simply not an accurate
reflection of the codebase. The design of the fallback mechanism and the amount
of issues that have gone through it is a great example.

The issues I have fixed along the way, and the chaotic way in which the API
has evolved have put me to reflect well on a proper design of the firmware API.

> > > :(
> > > 
> > > Seriously, why?  Why are we extending any of this at all? 
> > 
> > Addressing easy extensibility was a prerequisite of considering firmware 
> > signing
> > support. Its really the *only* reason I started reviewing the firmware API, 
> > to the
> > point I started helping fix quite a bit of bugs and now just became the 
> > maintainer.
> > 
> > So my original firmware signing effort, now driven by AKASHI Takahiro, was 
> > one
> > of the original motivations here!
> 
> But we don't accept kernel patches for some mythical future option that
> might be happening some time in the future.

Greg, these are non mythical "future options" -- they are real feature requests
and they have all valid reasons and discussions ongoing on the mailing list. The
streaming FPGA support is a concrete valid use case we need to extend *now* and
your reply brilliantly seems to have completely ignored it.

I do agree that firmware signing itself was a largely debatable topic, there
were *really-really* long threads on the topic. However we had a hallway track
at Santa Fe Plumbers where it seemed we reached consensus on a path forward!
The firmware signing topic should be addressed on TAKASHI's patch set [0]. 
Please
address your NACK and reasons there. Even though it is based on the driver
data API, the main topic points of *logic* for it can *also* be discussed
there.

BUT NOTE:

Before we could move forward with firmware signing we need also a *sane* way to
extend the API to address the needs of firmware signing. So a proper sane API
for future extensions is in order as a prerequisite. This goes along with
testing and documentation.

This goes for *any* new firmware API feature!!!

Firmware signing was just one example feature!!!

Also -- even if they were "mythical" the *point* of this series is to address
extensibility of the API, and so one of the ways to measure the gains of the
design of a new API is to look at what the code would look like when new
features are added. This is why I pointed out to review these proposed changes.

Even more so given I am noting that these are non-mythical 

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Luis R. Rodriguez]

On Sat, Jun 17, 2017 at 09:38:15PM +0200, Greg KH wrote:
> On Tue, Jun 13, 2017 at 09:40:11PM +0200, Luis R. Rodriguez wrote:
> > On Tue, Jun 13, 2017 at 11:05:48AM +0200, Greg KH wrote:
> > > On Mon, Jun 05, 2017 at 02:39:33PM -0700, Luis R. Rodriguez wrote:
> > > > As the firmware API evolves we keep extending functions with more 
> > > > arguments.
> > > > Stop this nonsense by proving an extensible data structure which can be 
> > > > used
> > > > to represent both user parameters and private internal parameters.
> > > 
> > > Let's take a simple C function interface and make it a more complex
> > > data-driven interface that is impossible to understand and obviously
> > > understand how it is to be used and works!
> > 
> > The firmware codebase was already complex!
> 
> Heh, I'm not arguing with you there :)

Great!

> > What you have to ask yourself really is if this makes it *less complex* and
> > helps *clean things up* in a much better way than it was before. Also does 
> > it
> > allow us to *pave the way for new functionality easily*, without creating
> > further mess?
> 
> I agree, that's what I'm saying here.  I just do not see that happening
> with your patch set at all.  It's adding more code, a more complex way
> to interact with the subsystem, and not making driver writer lives any
> easier at all that I can see.

There are two things to consider:

a) The current design of the firmware API, and interfaces with exported symbols

The case for the driver data API was that we were being super sloppy with 
extensions,
to the point was making the internal code base very bug prone and full or 
redirect
conditionals with #ifdefery nightmware stuff.
   
b) Features of the firmware API

These have to be evaluated on a case by case basis.

> Again, the code is now bigger, does more, with not even any real benefit
> for existing users.

Obviously I disagree strongly, in light of the history of the code. Not only
should the existing code be compared but also how it has evolved and we should
evaluate whether or not its evolution can be dealt with more appropriately.

> > If not, what concrete alternatives do you suggest?
> 
> It's working, so leave it alone?  :)

As the maintainer of the firmware API I **totally** disagree!!

First the firmware API has been evolving as pieces of gum thrown at it. A
proper design of the API in consideration of extensions is in order.  Likewise
goes for testing and documentation. Second, it cannot be said with any serious
tone that the current design has worked well.  It is simply not an accurate
reflection of the codebase. The design of the fallback mechanism and the amount
of issues that have gone through it is a great example.

The issues I have fixed along the way, and the chaotic way in which the API
has evolved have put me to reflect well on a proper design of the firmware API.

> > > :(
> > > 
> > > Seriously, why?  Why are we extending any of this at all? 
> > 
> > Addressing easy extensibility was a prerequisite of considering firmware 
> > signing
> > support. Its really the *only* reason I started reviewing the firmware API, 
> > to the
> > point I started helping fix quite a bit of bugs and now just became the 
> > maintainer.
> > 
> > So my original firmware signing effort, now driven by AKASHI Takahiro, was 
> > one
> > of the original motivations here!
> 
> But we don't accept kernel patches for some mythical future option that
> might be happening some time in the future.

Greg, these are non mythical "future options" -- they are real feature requests
and they have all valid reasons and discussions ongoing on the mailing list. The
streaming FPGA support is a concrete valid use case we need to extend *now* and
your reply brilliantly seems to have completely ignored it.

I do agree that firmware signing itself was a largely debatable topic, there
were *really-really* long threads on the topic. However we had a hallway track
at Santa Fe Plumbers where it seemed we reached consensus on a path forward!
The firmware signing topic should be addressed on TAKASHI's patch set [0]. 
Please
address your NACK and reasons there. Even though it is based on the driver
data API, the main topic points of *logic* for it can *also* be discussed
there.

BUT NOTE:

Before we could move forward with firmware signing we need also a *sane* way to
extend the API to address the needs of firmware signing. So a proper sane API
for future extensions is in order as a prerequisite. This goes along with
testing and documentation.

This goes for *any* new firmware API feature!!!

Firmware signing was just one example feature!!!

Also -- even if they were "mythical" the *point* of this series is to address
extensibility of the API, and so one of the ways to measure the gains of the
design of a new API is to look at what the code would look like when new
features are added. This is why I pointed out to review these proposed changes.

Even more so given I am noting that these are non-mythical 

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Johannes Berg]

On Sat, 2017-06-17 at 21:38 +0200, Greg KH wrote:

> But we don't accept kernel patches for some mythical future option
> that might be happening some time in the future.  Heck, I'm still not
> convinced that firmware signing isn't anything more than just some
> snakeoil in the first place!

I for one really want the "firmware" signing, because I want to load
the regulatory database through this API, and 

But honestly, I've been waiting for years for that now and started
looking at what it would take to hand-implement that on top of the
existing firmware API. Probably not all that much.

johannes

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Johannes Berg]

On Sat, 2017-06-17 at 21:38 +0200, Greg KH wrote:

> But we don't accept kernel patches for some mythical future option
> that might be happening some time in the future.  Heck, I'm still not
> convinced that firmware signing isn't anything more than just some
> snakeoil in the first place!

I for one really want the "firmware" signing, because I want to load
the regulatory database through this API, and 

But honestly, I've been waiting for years for that now and started
looking at what it would take to hand-implement that on top of the
existing firmware API. Probably not all that much.

johannes

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Greg KH]

On Tue, Jun 13, 2017 at 09:40:11PM +0200, Luis R. Rodriguez wrote:
> On Tue, Jun 13, 2017 at 11:05:48AM +0200, Greg KH wrote:
> > On Mon, Jun 05, 2017 at 02:39:33PM -0700, Luis R. Rodriguez wrote:
> > > As the firmware API evolves we keep extending functions with more 
> > > arguments.
> > > Stop this nonsense by proving an extensible data structure which can be 
> > > used
> > > to represent both user parameters and private internal parameters.
> > 
> > Let's take a simple C function interface and make it a more complex
> > data-driven interface that is impossible to understand and obviously
> > understand how it is to be used and works!
> 
> The firmware codebase was already complex!

Heh, I'm not arguing with you there :)

> What you have to ask yourself really is if this makes it *less complex* and
> helps *clean things up* in a much better way than it was before. Also does it
> allow us to *pave the way for new functionality easily*, without creating
> further mess?

I agree, that's what I'm saying here.  I just do not see that happening
with your patch set at all.  It's adding more code, a more complex way
to interact with the subsystem, and not making driver writer lives any
easier at all that I can see.

Again, the code is now bigger, does more, with not even any real benefit
for existing users.

> If not, what concrete alternatives do you suggest?

It's working, so leave it alone?  :)

> > :(
> > 
> > Seriously, why?  Why are we extending any of this at all? 
> 
> Addressing easy extensibility was a prerequisite of considering firmware 
> signing
> support. Its really the *only* reason I started reviewing the firmware API, 
> to the
> point I started helping fix quite a bit of bugs and now just became the 
> maintainer.
> 
> So my original firmware signing effort, now driven by AKASHI Takahiro, was one
> of the original motivations here!

But we don't accept kernel patches for some mythical future option that
might be happening some time in the future.  Heck, I'm still not
convinced that firmware signing isn't anything more than just some
snakeoil in the first place!

So while you mention lots of times that all sorts of wonderful things
can now possibly be built on top of the new code, I have yet to see it
(meaning you didn't include it in the patch series.)

To get me to take these changes, you have to show a real need and user
of the code.  Without that it just strongly looks like you are having
fun making a more complex api for no reason that we are then going to be
stuck with maintaining.

So clean away, and fix up, but remember, you have to be able to justify
each change as being needed.  And so far, I'm not sold on this at all,
sorry.

thanks,

greg k-h

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Greg KH]

On Tue, Jun 13, 2017 at 09:40:11PM +0200, Luis R. Rodriguez wrote:
> On Tue, Jun 13, 2017 at 11:05:48AM +0200, Greg KH wrote:
> > On Mon, Jun 05, 2017 at 02:39:33PM -0700, Luis R. Rodriguez wrote:
> > > As the firmware API evolves we keep extending functions with more 
> > > arguments.
> > > Stop this nonsense by proving an extensible data structure which can be 
> > > used
> > > to represent both user parameters and private internal parameters.
> > 
> > Let's take a simple C function interface and make it a more complex
> > data-driven interface that is impossible to understand and obviously
> > understand how it is to be used and works!
> 
> The firmware codebase was already complex!

Heh, I'm not arguing with you there :)

> What you have to ask yourself really is if this makes it *less complex* and
> helps *clean things up* in a much better way than it was before. Also does it
> allow us to *pave the way for new functionality easily*, without creating
> further mess?

I agree, that's what I'm saying here.  I just do not see that happening
with your patch set at all.  It's adding more code, a more complex way
to interact with the subsystem, and not making driver writer lives any
easier at all that I can see.

Again, the code is now bigger, does more, with not even any real benefit
for existing users.

> If not, what concrete alternatives do you suggest?

It's working, so leave it alone?  :)

> > :(
> > 
> > Seriously, why?  Why are we extending any of this at all? 
> 
> Addressing easy extensibility was a prerequisite of considering firmware 
> signing
> support. Its really the *only* reason I started reviewing the firmware API, 
> to the
> point I started helping fix quite a bit of bugs and now just became the 
> maintainer.
> 
> So my original firmware signing effort, now driven by AKASHI Takahiro, was one
> of the original motivations here!

But we don't accept kernel patches for some mythical future option that
might be happening some time in the future.  Heck, I'm still not
convinced that firmware signing isn't anything more than just some
snakeoil in the first place!

So while you mention lots of times that all sorts of wonderful things
can now possibly be built on top of the new code, I have yet to see it
(meaning you didn't include it in the patch series.)

To get me to take these changes, you have to show a real need and user
of the code.  Without that it just strongly looks like you are having
fun making a more complex api for no reason that we are then going to be
stuck with maintaining.

So clean away, and fix up, but remember, you have to be able to justify
each change as being needed.  And so far, I'm not sold on this at all,
sorry.

thanks,

greg k-h

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Li, Yi]

On 6/13/2017 2:40 PM, Luis R. Rodriguez wrote:

On Tue, Jun 13, 2017 at 11:05:48AM +0200, Greg KH wrote:

On Mon, Jun 05, 2017 at 02:39:33PM -0700, Luis R. Rodriguez wrote:

As the firmware API evolves we keep extending functions with more arguments.
Stop this nonsense by proving an extensible data structure which can be used
to represent both user parameters and private internal parameters.


Let's take a simple C function interface and make it a more complex
data-driven interface that is impossible to understand and obviously
understand how it is to be used and works!


The firmware codebase was already complex!

What you have to ask yourself really is if this makes it *less complex* and
helps *clean things up* in a much better way than it was before. Also does it
allow us to *pave the way for new functionality easily*, without creating
further mess?

If not, what concrete alternatives do you suggest?


:(

Seriously, why?  Why are we extending any of this at all?


Addressing easy extensibility was a prerequisite of considering firmware signing
support. Its really the *only* reason I started reviewing the firmware API, to 
the
point I started helping fix quite a bit of bugs and now just became the 
maintainer.

So my original firmware signing effort, now driven by AKASHI Takahiro, was one
of the original motivations here!

I asked:

How we should properly extend the API for new functionality in *a real
clean way* ? This also means cleaning under the rug!

Ease of extensibility is a need we have as otherwise we end up in the same
situation as before, we end up having to add new functionality by extending the
number of arguments to an sync or async call, and as collateral have to changes
*tons* of callers. I think you and I agree on this, correct me if I'm wrong?

Another issue to address when deciding when there is merit for a new API call,
instead of just folding functionality into flags. For this its best consider
not only the future but also what was done in the past given some new desirable
functionality relies on existing mechanisms.

The approach Rafał took does what I do just that it forgets about cleaning
underneath the rug, so I really cannot see how its any different. Case in
point, we have functionality in place today to support no-cache, yet this is a
hidden feature, used implicitly only for one API call, there has been requests
to support the no-cache functionality by Johannes for iwlwifi long ago for the
async call given *they* do their own caching.  How do you suggest do we take
the no-cache functionality used only internally for another API call and apply
it for async?  Do we make a new exported symbol ? Or do we expose this as a
flag on a regular async call?  With the approach I take we expose the internal
functionality clearly and later Li Yi folds it as public API through a
parameter for the async API. Later he extends iwlwifi with just 2 lines of code
to get this functionality. This would later also be used by some other
functionality he's interested in!


Echo, the firmware caching part is indeed complicated. :) Taking example 
of the 10 seconds rule of uncaching, bad things could happen if the end 
drivers could not complete the programming within the time limit or the 
firmware files was removed from filesystem. It might be safer to let end 
drivers to free the cache? Anyway it should only be enabled by those 
drivers need to re-program firmware during suspend/resume instead of as 
an default option, which is expensive for the base firmware class to do 
on each PM cycle.


I do like the concept of expending features as parameters instead of 
adding new API functions.




Another good example is that the optional call request_firmware_direct() is for
sync, but async also has the same need --  do we add a new API call just for
the same purpose or do we fold some of this functionality as flags?

How do we properly keep evolving functionality for the firmware API? We have
to consider existing features, perhaps some hidden, and new features coming
down the pipe line.

Please take the time to think about all this for a bit, not only the past but
also all the incoming set of features in the pipeline! The FPGA streaming
support for instance reuses the no-cache "internal hidden feature", as well as
the existing request_firmware_into_buf() with some slight variations!  We could
just fold both requirements as parameters.


This series adds a ton of new "features"


Actually, it *purposely* only folded the optional nature of firmware for async
and added support for enabling drivers to daisy chain requests using a simple
api numbering scheme as a counter to complex internal driver mechanisms --
Intel's solution actually used recursion. I split out this work on its own
series after a long history of working on firmware singing support. I'm now
also cleaning under the rug.

I purposely limited the amount of "features" to get proper review.


and complexity,


The difficulty to 

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Li, Yi]

On 6/13/2017 2:40 PM, Luis R. Rodriguez wrote:

On Tue, Jun 13, 2017 at 11:05:48AM +0200, Greg KH wrote:

On Mon, Jun 05, 2017 at 02:39:33PM -0700, Luis R. Rodriguez wrote:

As the firmware API evolves we keep extending functions with more arguments.
Stop this nonsense by proving an extensible data structure which can be used
to represent both user parameters and private internal parameters.


Let's take a simple C function interface and make it a more complex
data-driven interface that is impossible to understand and obviously
understand how it is to be used and works!


The firmware codebase was already complex!

What you have to ask yourself really is if this makes it *less complex* and
helps *clean things up* in a much better way than it was before. Also does it
allow us to *pave the way for new functionality easily*, without creating
further mess?

If not, what concrete alternatives do you suggest?


:(

Seriously, why?  Why are we extending any of this at all?


Addressing easy extensibility was a prerequisite of considering firmware signing
support. Its really the *only* reason I started reviewing the firmware API, to 
the
point I started helping fix quite a bit of bugs and now just became the 
maintainer.

So my original firmware signing effort, now driven by AKASHI Takahiro, was one
of the original motivations here!

I asked:

How we should properly extend the API for new functionality in *a real
clean way* ? This also means cleaning under the rug!

Ease of extensibility is a need we have as otherwise we end up in the same
situation as before, we end up having to add new functionality by extending the
number of arguments to an sync or async call, and as collateral have to changes
*tons* of callers. I think you and I agree on this, correct me if I'm wrong?

Another issue to address when deciding when there is merit for a new API call,
instead of just folding functionality into flags. For this its best consider
not only the future but also what was done in the past given some new desirable
functionality relies on existing mechanisms.

The approach Rafał took does what I do just that it forgets about cleaning
underneath the rug, so I really cannot see how its any different. Case in
point, we have functionality in place today to support no-cache, yet this is a
hidden feature, used implicitly only for one API call, there has been requests
to support the no-cache functionality by Johannes for iwlwifi long ago for the
async call given *they* do their own caching.  How do you suggest do we take
the no-cache functionality used only internally for another API call and apply
it for async?  Do we make a new exported symbol ? Or do we expose this as a
flag on a regular async call?  With the approach I take we expose the internal
functionality clearly and later Li Yi folds it as public API through a
parameter for the async API. Later he extends iwlwifi with just 2 lines of code
to get this functionality. This would later also be used by some other
functionality he's interested in!


Echo, the firmware caching part is indeed complicated. :) Taking example 
of the 10 seconds rule of uncaching, bad things could happen if the end 
drivers could not complete the programming within the time limit or the 
firmware files was removed from filesystem. It might be safer to let end 
drivers to free the cache? Anyway it should only be enabled by those 
drivers need to re-program firmware during suspend/resume instead of as 
an default option, which is expensive for the base firmware class to do 
on each PM cycle.


I do like the concept of expending features as parameters instead of 
adding new API functions.




Another good example is that the optional call request_firmware_direct() is for
sync, but async also has the same need --  do we add a new API call just for
the same purpose or do we fold some of this functionality as flags?

How do we properly keep evolving functionality for the firmware API? We have
to consider existing features, perhaps some hidden, and new features coming
down the pipe line.

Please take the time to think about all this for a bit, not only the past but
also all the incoming set of features in the pipeline! The FPGA streaming
support for instance reuses the no-cache "internal hidden feature", as well as
the existing request_firmware_into_buf() with some slight variations!  We could
just fold both requirements as parameters.


This series adds a ton of new "features"


Actually, it *purposely* only folded the optional nature of firmware for async
and added support for enabling drivers to daisy chain requests using a simple
api numbering scheme as a counter to complex internal driver mechanisms --
Intel's solution actually used recursion. I split out this work on its own
series after a long history of working on firmware singing support. I'm now
also cleaning under the rug.

I purposely limited the amount of "features" to get proper review.


and complexity,


The difficulty to 

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Luis R. Rodriguez]

On Tue, Jun 13, 2017 at 11:05:48AM +0200, Greg KH wrote:
> On Mon, Jun 05, 2017 at 02:39:33PM -0700, Luis R. Rodriguez wrote:
> > As the firmware API evolves we keep extending functions with more arguments.
> > Stop this nonsense by proving an extensible data structure which can be used
> > to represent both user parameters and private internal parameters.
> 
> Let's take a simple C function interface and make it a more complex
> data-driven interface that is impossible to understand and obviously
> understand how it is to be used and works!

The firmware codebase was already complex!

What you have to ask yourself really is if this makes it *less complex* and
helps *clean things up* in a much better way than it was before. Also does it
allow us to *pave the way for new functionality easily*, without creating
further mess?

If not, what concrete alternatives do you suggest?

> :(
> 
> Seriously, why?  Why are we extending any of this at all? 

Addressing easy extensibility was a prerequisite of considering firmware signing
support. Its really the *only* reason I started reviewing the firmware API, to 
the
point I started helping fix quite a bit of bugs and now just became the 
maintainer.

So my original firmware signing effort, now driven by AKASHI Takahiro, was one
of the original motivations here!

I asked:

How we should properly extend the API for new functionality in *a real
clean way* ? This also means cleaning under the rug!

Ease of extensibility is a need we have as otherwise we end up in the same
situation as before, we end up having to add new functionality by extending the
number of arguments to an sync or async call, and as collateral have to changes
*tons* of callers. I think you and I agree on this, correct me if I'm wrong?

Another issue to address when deciding when there is merit for a new API call,
instead of just folding functionality into flags. For this its best consider
not only the future but also what was done in the past given some new desirable
functionality relies on existing mechanisms.

The approach Rafał took does what I do just that it forgets about cleaning
underneath the rug, so I really cannot see how its any different. Case in
point, we have functionality in place today to support no-cache, yet this is a
hidden feature, used implicitly only for one API call, there has been requests
to support the no-cache functionality by Johannes for iwlwifi long ago for the
async call given *they* do their own caching.  How do you suggest do we take
the no-cache functionality used only internally for another API call and apply
it for async?  Do we make a new exported symbol ? Or do we expose this as a
flag on a regular async call?  With the approach I take we expose the internal
functionality clearly and later Li Yi folds it as public API through a
parameter for the async API. Later he extends iwlwifi with just 2 lines of code
to get this functionality. This would later also be used by some other
functionality he's interested in!

Another good example is that the optional call request_firmware_direct() is for
sync, but async also has the same need --  do we add a new API call just for
the same purpose or do we fold some of this functionality as flags?

How do we properly keep evolving functionality for the firmware API? We have
to consider existing features, perhaps some hidden, and new features coming
down the pipe line.

Please take the time to think about all this for a bit, not only the past but
also all the incoming set of features in the pipeline! The FPGA streaming
support for instance reuses the no-cache "internal hidden feature", as well as
the existing request_firmware_into_buf() with some slight variations!  We could
just fold both requirements as parameters.

> This series adds a ton of new "features"

Actually, it *purposely* only folded the optional nature of firmware for async
and added support for enabling drivers to daisy chain requests using a simple
api numbering scheme as a counter to complex internal driver mechanisms --
Intel's solution actually used recursion. I split out this work on its own
series after a long history of working on firmware singing support. I'm now
also cleaning under the rug.

I purposely limited the amount of "features" to get proper review.

> and complexity,

The difficulty to properly understand the firmware code *was there before*, so
I really do believe its unfair for you to say what I have come up with is
complex, question is if its less complex, and *easier* to understand than what
we had before. I'd argue it is easier to understand given 2 developers have
been working off on top of it now and seem to grok it rather well.

Today's code base's complexity is one of the reasons we also we have had quite
a bit of regressions. One of the other issues was lack of proper documentation,
which I have been fixing as of late, but also clearly documenting the purpose
and limitations each new feature. The confusing #ifef'ery over 

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Luis R. Rodriguez]

On Tue, Jun 13, 2017 at 11:05:48AM +0200, Greg KH wrote:
> On Mon, Jun 05, 2017 at 02:39:33PM -0700, Luis R. Rodriguez wrote:
> > As the firmware API evolves we keep extending functions with more arguments.
> > Stop this nonsense by proving an extensible data structure which can be used
> > to represent both user parameters and private internal parameters.
> 
> Let's take a simple C function interface and make it a more complex
> data-driven interface that is impossible to understand and obviously
> understand how it is to be used and works!

The firmware codebase was already complex!

What you have to ask yourself really is if this makes it *less complex* and
helps *clean things up* in a much better way than it was before. Also does it
allow us to *pave the way for new functionality easily*, without creating
further mess?

If not, what concrete alternatives do you suggest?

> :(
> 
> Seriously, why?  Why are we extending any of this at all? 

Addressing easy extensibility was a prerequisite of considering firmware signing
support. Its really the *only* reason I started reviewing the firmware API, to 
the
point I started helping fix quite a bit of bugs and now just became the 
maintainer.

So my original firmware signing effort, now driven by AKASHI Takahiro, was one
of the original motivations here!

I asked:

How we should properly extend the API for new functionality in *a real
clean way* ? This also means cleaning under the rug!

Ease of extensibility is a need we have as otherwise we end up in the same
situation as before, we end up having to add new functionality by extending the
number of arguments to an sync or async call, and as collateral have to changes
*tons* of callers. I think you and I agree on this, correct me if I'm wrong?

Another issue to address when deciding when there is merit for a new API call,
instead of just folding functionality into flags. For this its best consider
not only the future but also what was done in the past given some new desirable
functionality relies on existing mechanisms.

The approach Rafał took does what I do just that it forgets about cleaning
underneath the rug, so I really cannot see how its any different. Case in
point, we have functionality in place today to support no-cache, yet this is a
hidden feature, used implicitly only for one API call, there has been requests
to support the no-cache functionality by Johannes for iwlwifi long ago for the
async call given *they* do their own caching.  How do you suggest do we take
the no-cache functionality used only internally for another API call and apply
it for async?  Do we make a new exported symbol ? Or do we expose this as a
flag on a regular async call?  With the approach I take we expose the internal
functionality clearly and later Li Yi folds it as public API through a
parameter for the async API. Later he extends iwlwifi with just 2 lines of code
to get this functionality. This would later also be used by some other
functionality he's interested in!

Another good example is that the optional call request_firmware_direct() is for
sync, but async also has the same need --  do we add a new API call just for
the same purpose or do we fold some of this functionality as flags?

How do we properly keep evolving functionality for the firmware API? We have
to consider existing features, perhaps some hidden, and new features coming
down the pipe line.

Please take the time to think about all this for a bit, not only the past but
also all the incoming set of features in the pipeline! The FPGA streaming
support for instance reuses the no-cache "internal hidden feature", as well as
the existing request_firmware_into_buf() with some slight variations!  We could
just fold both requirements as parameters.

> This series adds a ton of new "features"

Actually, it *purposely* only folded the optional nature of firmware for async
and added support for enabling drivers to daisy chain requests using a simple
api numbering scheme as a counter to complex internal driver mechanisms --
Intel's solution actually used recursion. I split out this work on its own
series after a long history of working on firmware singing support. I'm now
also cleaning under the rug.

I purposely limited the amount of "features" to get proper review.

> and complexity,

The difficulty to properly understand the firmware code *was there before*, so
I really do believe its unfair for you to say what I have come up with is
complex, question is if its less complex, and *easier* to understand than what
we had before. I'd argue it is easier to understand given 2 developers have
been working off on top of it now and seem to grok it rather well.

Today's code base's complexity is one of the reasons we also we have had quite
a bit of regressions. One of the other issues was lack of proper documentation,
which I have been fixing as of late, but also clearly documenting the purpose
and limitations each new feature. The confusing #ifef'ery over 

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Greg KH]

On Tue, Jun 13, 2017 at 05:32:49PM +0200, Luis R. Rodriguez wrote:
> On Tue, Jun 13, 2017 at 03:17:43PM +0200, Greg KH wrote:
> > On Tue, Jun 13, 2017 at 12:31:04PM +0200, Rafał Miłecki wrote:
> > > On 2017-06-13 11:05, Greg KH wrote:
> > > > On Mon, Jun 05, 2017 at 02:39:33PM -0700, Luis R. Rodriguez wrote:
> > > > > As the firmware API evolves we keep extending functions with more
> > > > > arguments.
> > > > > Stop this nonsense by proving an extensible data structure which can
> > > > > be used
> > > > > to represent both user parameters and private internal parameters.
> > > > 
> > > > Let's take a simple C function interface and make it a more complex
> > > > data-driven interface that is impossible to understand and obviously
> > > > understand how it is to be used and works!
> > > > 
> > > > :(
> > > > 
> > > > Seriously, why?  Why are we extending any of this at all?  This series
> > > > adds a ton of new "features" and complexity, but for absolutely no gain.
> > > > 
> > > > Oh, I take it back, you removed 29 lines from the iwlwifi driver.
> > > > 
> > > > That's still not worth it at all, you have yet to sell me on this whole
> > > > complex beast.  I can't see why we need it, and if I, one of the few
> > > > people who thinks they actually understand this kernel interface, can't
> > > > see it, how can you sell it to someone else?
> > > > 
> > > > Sorry, but no, I'm still not going to take this series until you show
> > > > some _REAL_ benefit for it.
> > > 
> > > FWIW I saw (or maybe still see?) a need to extend request_firmware* API to
> > > allow silencing a warning if firmware file is missing.
> > > 
> > > I even sent a trivial patch adding support for this:
> > > [PATCH V4 1/2] firmware: add more flexible request_firmware_async function
> > > https://patchwork.kernel.org/patch/9588787/
> > > (I think it still applies) but it got rejected due to Luis's big rework.
> > 
> > Can you resend this series if it still does apply?
> 
> FWIW just some notes on Rafał's series:
> 
> someone else brought up second that his second no longer should be applied as
> some devices do need what seems to be today's optional request. Also note that
> the approach follows the same I take, just struct a firmware_opts instead of
> driver params... and it does not mesh up the old options as I did in my first
> patch in this series.

As I have no idea what his series looks like at the moment, why not wait
until they are posted again to review them? :)

thanks,

greg k-h

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Greg KH]

On Tue, Jun 13, 2017 at 05:32:49PM +0200, Luis R. Rodriguez wrote:
> On Tue, Jun 13, 2017 at 03:17:43PM +0200, Greg KH wrote:
> > On Tue, Jun 13, 2017 at 12:31:04PM +0200, Rafał Miłecki wrote:
> > > On 2017-06-13 11:05, Greg KH wrote:
> > > > On Mon, Jun 05, 2017 at 02:39:33PM -0700, Luis R. Rodriguez wrote:
> > > > > As the firmware API evolves we keep extending functions with more
> > > > > arguments.
> > > > > Stop this nonsense by proving an extensible data structure which can
> > > > > be used
> > > > > to represent both user parameters and private internal parameters.
> > > > 
> > > > Let's take a simple C function interface and make it a more complex
> > > > data-driven interface that is impossible to understand and obviously
> > > > understand how it is to be used and works!
> > > > 
> > > > :(
> > > > 
> > > > Seriously, why?  Why are we extending any of this at all?  This series
> > > > adds a ton of new "features" and complexity, but for absolutely no gain.
> > > > 
> > > > Oh, I take it back, you removed 29 lines from the iwlwifi driver.
> > > > 
> > > > That's still not worth it at all, you have yet to sell me on this whole
> > > > complex beast.  I can't see why we need it, and if I, one of the few
> > > > people who thinks they actually understand this kernel interface, can't
> > > > see it, how can you sell it to someone else?
> > > > 
> > > > Sorry, but no, I'm still not going to take this series until you show
> > > > some _REAL_ benefit for it.
> > > 
> > > FWIW I saw (or maybe still see?) a need to extend request_firmware* API to
> > > allow silencing a warning if firmware file is missing.
> > > 
> > > I even sent a trivial patch adding support for this:
> > > [PATCH V4 1/2] firmware: add more flexible request_firmware_async function
> > > https://patchwork.kernel.org/patch/9588787/
> > > (I think it still applies) but it got rejected due to Luis's big rework.
> > 
> > Can you resend this series if it still does apply?
> 
> FWIW just some notes on Rafał's series:
> 
> someone else brought up second that his second no longer should be applied as
> some devices do need what seems to be today's optional request. Also note that
> the approach follows the same I take, just struct a firmware_opts instead of
> driver params... and it does not mesh up the old options as I did in my first
> patch in this series.

As I have no idea what his series looks like at the moment, why not wait
until they are posted again to review them? :)

thanks,

greg k-h

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Luis R. Rodriguez]

On Tue, Jun 13, 2017 at 03:17:43PM +0200, Greg KH wrote:
> On Tue, Jun 13, 2017 at 12:31:04PM +0200, Rafał Miłecki wrote:
> > On 2017-06-13 11:05, Greg KH wrote:
> > > On Mon, Jun 05, 2017 at 02:39:33PM -0700, Luis R. Rodriguez wrote:
> > > > As the firmware API evolves we keep extending functions with more
> > > > arguments.
> > > > Stop this nonsense by proving an extensible data structure which can
> > > > be used
> > > > to represent both user parameters and private internal parameters.
> > > 
> > > Let's take a simple C function interface and make it a more complex
> > > data-driven interface that is impossible to understand and obviously
> > > understand how it is to be used and works!
> > > 
> > > :(
> > > 
> > > Seriously, why?  Why are we extending any of this at all?  This series
> > > adds a ton of new "features" and complexity, but for absolutely no gain.
> > > 
> > > Oh, I take it back, you removed 29 lines from the iwlwifi driver.
> > > 
> > > That's still not worth it at all, you have yet to sell me on this whole
> > > complex beast.  I can't see why we need it, and if I, one of the few
> > > people who thinks they actually understand this kernel interface, can't
> > > see it, how can you sell it to someone else?
> > > 
> > > Sorry, but no, I'm still not going to take this series until you show
> > > some _REAL_ benefit for it.
> > 
> > FWIW I saw (or maybe still see?) a need to extend request_firmware* API to
> > allow silencing a warning if firmware file is missing.
> > 
> > I even sent a trivial patch adding support for this:
> > [PATCH V4 1/2] firmware: add more flexible request_firmware_async function
> > https://patchwork.kernel.org/patch/9588787/
> > (I think it still applies) but it got rejected due to Luis's big rework.
> 
> Can you resend this series if it still does apply?

FWIW just some notes on Rafał's series:

someone else brought up second that his second no longer should be applied as
some devices do need what seems to be today's optional request. Also note that
the approach follows the same I take, just struct a firmware_opts instead of
driver params... and it does not mesh up the old options as I did in my first
patch in this series.

  Luis

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Luis R. Rodriguez]

On Tue, Jun 13, 2017 at 03:17:43PM +0200, Greg KH wrote:
> On Tue, Jun 13, 2017 at 12:31:04PM +0200, Rafał Miłecki wrote:
> > On 2017-06-13 11:05, Greg KH wrote:
> > > On Mon, Jun 05, 2017 at 02:39:33PM -0700, Luis R. Rodriguez wrote:
> > > > As the firmware API evolves we keep extending functions with more
> > > > arguments.
> > > > Stop this nonsense by proving an extensible data structure which can
> > > > be used
> > > > to represent both user parameters and private internal parameters.
> > > 
> > > Let's take a simple C function interface and make it a more complex
> > > data-driven interface that is impossible to understand and obviously
> > > understand how it is to be used and works!
> > > 
> > > :(
> > > 
> > > Seriously, why?  Why are we extending any of this at all?  This series
> > > adds a ton of new "features" and complexity, but for absolutely no gain.
> > > 
> > > Oh, I take it back, you removed 29 lines from the iwlwifi driver.
> > > 
> > > That's still not worth it at all, you have yet to sell me on this whole
> > > complex beast.  I can't see why we need it, and if I, one of the few
> > > people who thinks they actually understand this kernel interface, can't
> > > see it, how can you sell it to someone else?
> > > 
> > > Sorry, but no, I'm still not going to take this series until you show
> > > some _REAL_ benefit for it.
> > 
> > FWIW I saw (or maybe still see?) a need to extend request_firmware* API to
> > allow silencing a warning if firmware file is missing.
> > 
> > I even sent a trivial patch adding support for this:
> > [PATCH V4 1/2] firmware: add more flexible request_firmware_async function
> > https://patchwork.kernel.org/patch/9588787/
> > (I think it still applies) but it got rejected due to Luis's big rework.
> 
> Can you resend this series if it still does apply?

FWIW just some notes on Rafał's series:

someone else brought up second that his second no longer should be applied as
some devices do need what seems to be today's optional request. Also note that
the approach follows the same I take, just struct a firmware_opts instead of
driver params... and it does not mesh up the old options as I did in my first
patch in this series.

  Luis

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Rafał Miłecki]

On 06/13/2017 03:17 PM, Greg KH wrote:

On Tue, Jun 13, 2017 at 12:31:04PM +0200, Rafał Miłecki wrote:

On 2017-06-13 11:05, Greg KH wrote:

On Mon, Jun 05, 2017 at 02:39:33PM -0700, Luis R. Rodriguez wrote:

As the firmware API evolves we keep extending functions with more
arguments.
Stop this nonsense by proving an extensible data structure which can
be used
to represent both user parameters and private internal parameters.


Let's take a simple C function interface and make it a more complex
data-driven interface that is impossible to understand and obviously
understand how it is to be used and works!

:(

Seriously, why?  Why are we extending any of this at all?  This series
adds a ton of new "features" and complexity, but for absolutely no gain.

Oh, I take it back, you removed 29 lines from the iwlwifi driver.

That's still not worth it at all, you have yet to sell me on this whole
complex beast.  I can't see why we need it, and if I, one of the few
people who thinks they actually understand this kernel interface, can't
see it, how can you sell it to someone else?

Sorry, but no, I'm still not going to take this series until you show
some _REAL_ benefit for it.


FWIW I saw (or maybe still see?) a need to extend request_firmware* API to
allow silencing a warning if firmware file is missing.

I even sent a trivial patch adding support for this:
[PATCH V4 1/2] firmware: add more flexible request_firmware_async function
https://patchwork.kernel.org/patch/9588787/
(I think it still applies) but it got rejected due to Luis's big rework.


Can you resend this series if it still does apply?


Sure, if you think it's worth trying, I'll do that!



And what exact warning is this silencing?  Normally we want the warning
there, as that implies that something is wrong if the firmware file that
a driver is asking for is not present.  That way the user can know to go
fix it up, right?


It's because brcmfmac looks for NVRAM in two places: /lib/firmware/ and
platform NVRAM. It's supposed to silence
[   10.801506] brcmfmac :01:00.0: Direct firmware load for 
brcm/brcmfmac43602-pcie.txt failed with error -2
in case there is platform NVRAM present.

For more details please take a look at:
[PATCH V4 2/2] brcmfmac: don't warn user about NVRAM if fallback to platform 
one succeeds
https://patchwork.kernel.org/patch/9588791/

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Rafał Miłecki]

On 06/13/2017 03:17 PM, Greg KH wrote:

On Tue, Jun 13, 2017 at 12:31:04PM +0200, Rafał Miłecki wrote:

On 2017-06-13 11:05, Greg KH wrote:

On Mon, Jun 05, 2017 at 02:39:33PM -0700, Luis R. Rodriguez wrote:

As the firmware API evolves we keep extending functions with more
arguments.
Stop this nonsense by proving an extensible data structure which can
be used
to represent both user parameters and private internal parameters.


Let's take a simple C function interface and make it a more complex
data-driven interface that is impossible to understand and obviously
understand how it is to be used and works!

:(

Seriously, why?  Why are we extending any of this at all?  This series
adds a ton of new "features" and complexity, but for absolutely no gain.

Oh, I take it back, you removed 29 lines from the iwlwifi driver.

That's still not worth it at all, you have yet to sell me on this whole
complex beast.  I can't see why we need it, and if I, one of the few
people who thinks they actually understand this kernel interface, can't
see it, how can you sell it to someone else?

Sorry, but no, I'm still not going to take this series until you show
some _REAL_ benefit for it.


FWIW I saw (or maybe still see?) a need to extend request_firmware* API to
allow silencing a warning if firmware file is missing.

I even sent a trivial patch adding support for this:
[PATCH V4 1/2] firmware: add more flexible request_firmware_async function
https://patchwork.kernel.org/patch/9588787/
(I think it still applies) but it got rejected due to Luis's big rework.


Can you resend this series if it still does apply?


Sure, if you think it's worth trying, I'll do that!



And what exact warning is this silencing?  Normally we want the warning
there, as that implies that something is wrong if the firmware file that
a driver is asking for is not present.  That way the user can know to go
fix it up, right?


It's because brcmfmac looks for NVRAM in two places: /lib/firmware/ and
platform NVRAM. It's supposed to silence
[   10.801506] brcmfmac :01:00.0: Direct firmware load for 
brcm/brcmfmac43602-pcie.txt failed with error -2
in case there is platform NVRAM present.

For more details please take a look at:
[PATCH V4 2/2] brcmfmac: don't warn user about NVRAM if fallback to platform 
one succeeds
https://patchwork.kernel.org/patch/9588791/

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Greg KH]

On Tue, Jun 13, 2017 at 12:31:04PM +0200, Rafał Miłecki wrote:
> On 2017-06-13 11:05, Greg KH wrote:
> > On Mon, Jun 05, 2017 at 02:39:33PM -0700, Luis R. Rodriguez wrote:
> > > As the firmware API evolves we keep extending functions with more
> > > arguments.
> > > Stop this nonsense by proving an extensible data structure which can
> > > be used
> > > to represent both user parameters and private internal parameters.
> > 
> > Let's take a simple C function interface and make it a more complex
> > data-driven interface that is impossible to understand and obviously
> > understand how it is to be used and works!
> > 
> > :(
> > 
> > Seriously, why?  Why are we extending any of this at all?  This series
> > adds a ton of new "features" and complexity, but for absolutely no gain.
> > 
> > Oh, I take it back, you removed 29 lines from the iwlwifi driver.
> > 
> > That's still not worth it at all, you have yet to sell me on this whole
> > complex beast.  I can't see why we need it, and if I, one of the few
> > people who thinks they actually understand this kernel interface, can't
> > see it, how can you sell it to someone else?
> > 
> > Sorry, but no, I'm still not going to take this series until you show
> > some _REAL_ benefit for it.
> 
> FWIW I saw (or maybe still see?) a need to extend request_firmware* API to
> allow silencing a warning if firmware file is missing.
> 
> I even sent a trivial patch adding support for this:
> [PATCH V4 1/2] firmware: add more flexible request_firmware_async function
> https://patchwork.kernel.org/patch/9588787/
> (I think it still applies) but it got rejected due to Luis's big rework.

Can you resend this series if it still does apply?

And what exact warning is this silencing?  Normally we want the warning
there, as that implies that something is wrong if the firmware file that
a driver is asking for is not present.  That way the user can know to go
fix it up, right?

thanks,

greg k-h

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Greg KH]

On Tue, Jun 13, 2017 at 12:31:04PM +0200, Rafał Miłecki wrote:
> On 2017-06-13 11:05, Greg KH wrote:
> > On Mon, Jun 05, 2017 at 02:39:33PM -0700, Luis R. Rodriguez wrote:
> > > As the firmware API evolves we keep extending functions with more
> > > arguments.
> > > Stop this nonsense by proving an extensible data structure which can
> > > be used
> > > to represent both user parameters and private internal parameters.
> > 
> > Let's take a simple C function interface and make it a more complex
> > data-driven interface that is impossible to understand and obviously
> > understand how it is to be used and works!
> > 
> > :(
> > 
> > Seriously, why?  Why are we extending any of this at all?  This series
> > adds a ton of new "features" and complexity, but for absolutely no gain.
> > 
> > Oh, I take it back, you removed 29 lines from the iwlwifi driver.
> > 
> > That's still not worth it at all, you have yet to sell me on this whole
> > complex beast.  I can't see why we need it, and if I, one of the few
> > people who thinks they actually understand this kernel interface, can't
> > see it, how can you sell it to someone else?
> > 
> > Sorry, but no, I'm still not going to take this series until you show
> > some _REAL_ benefit for it.
> 
> FWIW I saw (or maybe still see?) a need to extend request_firmware* API to
> allow silencing a warning if firmware file is missing.
> 
> I even sent a trivial patch adding support for this:
> [PATCH V4 1/2] firmware: add more flexible request_firmware_async function
> https://patchwork.kernel.org/patch/9588787/
> (I think it still applies) but it got rejected due to Luis's big rework.

Can you resend this series if it still does apply?

And what exact warning is this silencing?  Normally we want the warning
there, as that implies that something is wrong if the firmware file that
a driver is asking for is not present.  That way the user can know to go
fix it up, right?

thanks,

greg k-h

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Rafał Miłecki]

On 2017-06-13 11:05, Greg KH wrote:

On Mon, Jun 05, 2017 at 02:39:33PM -0700, Luis R. Rodriguez wrote:
As the firmware API evolves we keep extending functions with more 
arguments.
Stop this nonsense by proving an extensible data structure which can 
be used

to represent both user parameters and private internal parameters.


Let's take a simple C function interface and make it a more complex
data-driven interface that is impossible to understand and obviously
understand how it is to be used and works!

:(

Seriously, why?  Why are we extending any of this at all?  This series
adds a ton of new "features" and complexity, but for absolutely no 
gain.


Oh, I take it back, you removed 29 lines from the iwlwifi driver.

That's still not worth it at all, you have yet to sell me on this whole
complex beast.  I can't see why we need it, and if I, one of the few
people who thinks they actually understand this kernel interface, can't
see it, how can you sell it to someone else?

Sorry, but no, I'm still not going to take this series until you show
some _REAL_ benefit for it.


FWIW I saw (or maybe still see?) a need to extend request_firmware* API 
to

allow silencing a warning if firmware file is missing.

I even sent a trivial patch adding support for this:
[PATCH V4 1/2] firmware: add more flexible request_firmware_async 
function

https://patchwork.kernel.org/patch/9588787/
(I think it still applies) but it got rejected due to Luis's big rework.

To be honest after seeing this big & more complex driver data API I just
gave up and decided I don't care about false problem reports that much 
:(

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Rafał Miłecki]

On 2017-06-13 11:05, Greg KH wrote:

On Mon, Jun 05, 2017 at 02:39:33PM -0700, Luis R. Rodriguez wrote:
As the firmware API evolves we keep extending functions with more 
arguments.
Stop this nonsense by proving an extensible data structure which can 
be used

to represent both user parameters and private internal parameters.


Let's take a simple C function interface and make it a more complex
data-driven interface that is impossible to understand and obviously
understand how it is to be used and works!

:(

Seriously, why?  Why are we extending any of this at all?  This series
adds a ton of new "features" and complexity, but for absolutely no 
gain.


Oh, I take it back, you removed 29 lines from the iwlwifi driver.

That's still not worth it at all, you have yet to sell me on this whole
complex beast.  I can't see why we need it, and if I, one of the few
people who thinks they actually understand this kernel interface, can't
see it, how can you sell it to someone else?

Sorry, but no, I'm still not going to take this series until you show
some _REAL_ benefit for it.


FWIW I saw (or maybe still see?) a need to extend request_firmware* API 
to

allow silencing a warning if firmware file is missing.

I even sent a trivial patch adding support for this:
[PATCH V4 1/2] firmware: add more flexible request_firmware_async 
function

https://patchwork.kernel.org/patch/9588787/
(I think it still applies) but it got rejected due to Luis's big rework.

To be honest after seeing this big & more complex driver data API I just
gave up and decided I don't care about false problem reports that much 
:(

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Greg KH]

On Mon, Jun 05, 2017 at 02:39:33PM -0700, Luis R. Rodriguez wrote:
> As the firmware API evolves we keep extending functions with more arguments.
> Stop this nonsense by proving an extensible data structure which can be used
> to represent both user parameters and private internal parameters.

Let's take a simple C function interface and make it a more complex
data-driven interface that is impossible to understand and obviously
understand how it is to be used and works!

:(

Seriously, why?  Why are we extending any of this at all?  This series
adds a ton of new "features" and complexity, but for absolutely no gain.

Oh, I take it back, you removed 29 lines from the iwlwifi driver.

That's still not worth it at all, you have yet to sell me on this whole
complex beast.  I can't see why we need it, and if I, one of the few
people who thinks they actually understand this kernel interface, can't
see it, how can you sell it to someone else?

Sorry, but no, I'm still not going to take this series until you show
some _REAL_ benefit for it.

thanks,

greg k-h

Re: [PATCH v9 1/5] firmware: add extensible driver data params

[Greg KH]

On Mon, Jun 05, 2017 at 02:39:33PM -0700, Luis R. Rodriguez wrote:
> As the firmware API evolves we keep extending functions with more arguments.
> Stop this nonsense by proving an extensible data structure which can be used
> to represent both user parameters and private internal parameters.

Let's take a simple C function interface and make it a more complex
data-driven interface that is impossible to understand and obviously
understand how it is to be used and works!

:(

Seriously, why?  Why are we extending any of this at all?  This series
adds a ton of new "features" and complexity, but for absolutely no gain.

Oh, I take it back, you removed 29 lines from the iwlwifi driver.

That's still not worth it at all, you have yet to sell me on this whole
complex beast.  I can't see why we need it, and if I, one of the few
people who thinks they actually understand this kernel interface, can't
see it, how can you sell it to someone else?

Sorry, but no, I'm still not going to take this series until you show
some _REAL_ benefit for it.

thanks,

greg k-h

[PATCH v9 1/5] firmware: add extensible driver data params

[Luis R. Rodriguez]

As the firmware API evolves we keep extending functions with more arguments.
Stop this nonsense by proving an extensible data structure which can be used
to represent both user parameters and private internal parameters.

We introduce 3 data structures:

  o struct driver_data_req_params  - used for user specified parameters
  o struct driver_data_priv_params - used for internal use only
  o struct driver_data_params - stiches both of the the above together,
only for internal use

This starts off by just making the existing APIs use the new data
structures, it will make subsequent changes easier to review which will
be adding new flexible APIs.

A side consequences is get to replace all the old internal "firmware
behavior  options" flags with enums we properly document, remove the
blinding #ifdefs, and compartamentlize the userhelper fallback code
more appropriately unde CONFIG_FW_LOADER_USER_HELPER_FALLBACK.

This commit should introduces no functional changes (TM).

Signed-off-by: Luis R. Rodriguez 
---
 drivers/base/firmware_class.c | 331 --
 include/linux/driver_data.h   |  89 
 2 files changed, 346 insertions(+), 74 deletions(-)
 create mode 100644 include/linux/driver_data.h

diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
index b9f907eedbf7..db7c0bc0ed98 100644
--- a/drivers/base/firmware_class.c
+++ b/drivers/base/firmware_class.c
@@ -19,6 +19,7 @@
 #include 
 #include 
 #include 
+#include 
 #include 
 #include 
 #include 
@@ -40,6 +41,149 @@ MODULE_AUTHOR("Manuel Estrada Sainz");
 MODULE_DESCRIPTION("Multi purpose firmware loading support");
 MODULE_LICENSE("GPL");
 
+/**
+ * enum driver_data_mode - driver data mode of operation
+ * @DRIVER_DATA_SYNC: used to determine if we should look for the driver data
+ * file immediatley.
+ * @DRIVER_DATA_ASYNC: used to determine if we should schedule the search for
+ * your driver data file to be run at a later time.
+ */
+enum driver_data_mode {
+   DRIVER_DATA_SYNC = 0,
+   DRIVER_DATA_ASYNC,
+};
+
+/**
+ * enum driver_data_priv_reqs - private features only used internally
+ *
+ * @DRIVER_DATA_PRIV_REQ_FALLBACK: specifies that the driver data request
+ * will use a fallback mechanism if the kernel's direct filesystem
+ * lookup failed to find the requested driver data. If the flag
+ * %DRIVER_DATA_PRIV_REQ_FALLBACK is set but the flag
+ * %DRIVER_DATA_PRIV_REQ_FALLBACK_UEVENT is not set, it means the caller
+ * is relying on a custom interface for driver data lookup as a fallback
+ * mechanism. The custom interface is expected to find any found driver
+ * data using the exposed sysfs interface of the firmware_class. If the
+ * custom fallback mechanism is not compatible with the internal caching
+ * mechanism for driver data lookups at resume, it will be disabled.
+ * @DRIVER_DATA_PRIV_REQ_FALLBACK_UEVENT: indicates that the fallback mechanism
+ * this driver data request will rely on will be that of having the kernel
+ * issue a uevent to userspace. Userspace in turn is expected to be
+ * monitoring for uevents for the firmware_class and will use the
+ * exposted sysfs interface to upload the driver data for the caller.
+ * @DRIVER_DATA_PRIV_REQ_NO_CACHE: indicates that the driver data request
+ * should not set up and use the internal caching mechanism to assist
+ * drivers from fetching driver data at resume time after suspend.
+ */
+enum driver_data_priv_reqs {
+   DRIVER_DATA_PRIV_REQ_FALLBACK   = 1 << 0,
+   DRIVER_DATA_PRIV_REQ_FALLBACK_UEVENT= 1 << 1,
+   DRIVER_DATA_PRIV_REQ_NO_CACHE   = 1 << 2,
+};
+
+/**
+ * struct driver_data_priv_params - private driver data parameters
+ * @mode: mode of operation
+ * @priv_reqs: private set of  driver_data_reqs, private requirements for
+ * the driver data request
+ * @alloc_buf: buffer area allocated by the caller so we can place the
+ * respective driver data
+ * @alloc_buf_size: size of the @alloc_buf
+ * @old_async_cb: used only for request_firmware_nowait() since we won't change
+ * all async callbacks to get the return value on failure
+ */
+struct driver_data_priv_params {
+   enum driver_data_mode mode;
+   u64 priv_reqs;
+   void *alloc_buf;
+   size_t alloc_buf_size;
+   void (*old_async_cb)(const struct firmware *driver_data, void *context);
+};
+
+/**
+ * struct driver_data_params
+ * @driver_data: the driver data if found using the requirements specified
+ * in @req_params and @priv_params
+ * @req_params: caller's requirements for the driver data to look for
+ * @priv_params: private requirements for the driver data to look for
+ */
+struct driver_data_params {
+   const struct firmware *driver_data;
+   const struct driver_data_req_params req_params;
+   struct driver_data_priv_params 

[PATCH v9 1/5] firmware: add extensible driver data params

[Luis R. Rodriguez]

As the firmware API evolves we keep extending functions with more arguments.
Stop this nonsense by proving an extensible data structure which can be used
to represent both user parameters and private internal parameters.

We introduce 3 data structures:

  o struct driver_data_req_params  - used for user specified parameters
  o struct driver_data_priv_params - used for internal use only
  o struct driver_data_params - stiches both of the the above together,
only for internal use

This starts off by just making the existing APIs use the new data
structures, it will make subsequent changes easier to review which will
be adding new flexible APIs.

A side consequences is get to replace all the old internal "firmware
behavior  options" flags with enums we properly document, remove the
blinding #ifdefs, and compartamentlize the userhelper fallback code
more appropriately unde CONFIG_FW_LOADER_USER_HELPER_FALLBACK.

This commit should introduces no functional changes (TM).

Signed-off-by: Luis R. Rodriguez 
---
 drivers/base/firmware_class.c | 331 --
 include/linux/driver_data.h   |  89 
 2 files changed, 346 insertions(+), 74 deletions(-)
 create mode 100644 include/linux/driver_data.h

diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
index b9f907eedbf7..db7c0bc0ed98 100644
--- a/drivers/base/firmware_class.c
+++ b/drivers/base/firmware_class.c
@@ -19,6 +19,7 @@
 #include 
 #include 
 #include 
+#include 
 #include 
 #include 
 #include 
@@ -40,6 +41,149 @@ MODULE_AUTHOR("Manuel Estrada Sainz");
 MODULE_DESCRIPTION("Multi purpose firmware loading support");
 MODULE_LICENSE("GPL");
 
+/**
+ * enum driver_data_mode - driver data mode of operation
+ * @DRIVER_DATA_SYNC: used to determine if we should look for the driver data
+ * file immediatley.
+ * @DRIVER_DATA_ASYNC: used to determine if we should schedule the search for
+ * your driver data file to be run at a later time.
+ */
+enum driver_data_mode {
+   DRIVER_DATA_SYNC = 0,
+   DRIVER_DATA_ASYNC,
+};
+
+/**
+ * enum driver_data_priv_reqs - private features only used internally
+ *
+ * @DRIVER_DATA_PRIV_REQ_FALLBACK: specifies that the driver data request
+ * will use a fallback mechanism if the kernel's direct filesystem
+ * lookup failed to find the requested driver data. If the flag
+ * %DRIVER_DATA_PRIV_REQ_FALLBACK is set but the flag
+ * %DRIVER_DATA_PRIV_REQ_FALLBACK_UEVENT is not set, it means the caller
+ * is relying on a custom interface for driver data lookup as a fallback
+ * mechanism. The custom interface is expected to find any found driver
+ * data using the exposed sysfs interface of the firmware_class. If the
+ * custom fallback mechanism is not compatible with the internal caching
+ * mechanism for driver data lookups at resume, it will be disabled.
+ * @DRIVER_DATA_PRIV_REQ_FALLBACK_UEVENT: indicates that the fallback mechanism
+ * this driver data request will rely on will be that of having the kernel
+ * issue a uevent to userspace. Userspace in turn is expected to be
+ * monitoring for uevents for the firmware_class and will use the
+ * exposted sysfs interface to upload the driver data for the caller.
+ * @DRIVER_DATA_PRIV_REQ_NO_CACHE: indicates that the driver data request
+ * should not set up and use the internal caching mechanism to assist
+ * drivers from fetching driver data at resume time after suspend.
+ */
+enum driver_data_priv_reqs {
+   DRIVER_DATA_PRIV_REQ_FALLBACK   = 1 << 0,
+   DRIVER_DATA_PRIV_REQ_FALLBACK_UEVENT= 1 << 1,
+   DRIVER_DATA_PRIV_REQ_NO_CACHE   = 1 << 2,
+};
+
+/**
+ * struct driver_data_priv_params - private driver data parameters
+ * @mode: mode of operation
+ * @priv_reqs: private set of  driver_data_reqs, private requirements for
+ * the driver data request
+ * @alloc_buf: buffer area allocated by the caller so we can place the
+ * respective driver data
+ * @alloc_buf_size: size of the @alloc_buf
+ * @old_async_cb: used only for request_firmware_nowait() since we won't change
+ * all async callbacks to get the return value on failure
+ */
+struct driver_data_priv_params {
+   enum driver_data_mode mode;
+   u64 priv_reqs;
+   void *alloc_buf;
+   size_t alloc_buf_size;
+   void (*old_async_cb)(const struct firmware *driver_data, void *context);
+};
+
+/**
+ * struct driver_data_params
+ * @driver_data: the driver data if found using the requirements specified
+ * in @req_params and @priv_params
+ * @req_params: caller's requirements for the driver data to look for
+ * @priv_params: private requirements for the driver data to look for
+ */
+struct driver_data_params {
+   const struct firmware *driver_data;
+   const struct driver_data_req_params req_params;
+   struct driver_data_priv_params priv_params;
+};
+