Re: [alsa-devel] [RFC PATCH 31/40] soundwire: intel: move shutdown() callback and don't export symbol

2019-08-23 Thread Pierre-Louis Bossart





+void intel_shutdown(struct snd_pcm_substream *substream,
+    struct snd_soc_dai *dai)
+{
+    struct sdw_cdns_dma_data *dma;
+
+    dma = snd_soc_dai_get_dma_data(dai, substream);
+    if (!dma)
+    return;
+
+    snd_soc_dai_set_dma_data(dai, substream, NULL);
+    kfree(dma);
+}


Correct me if I'm wrong, but do we really need to _get_dma_ here?
_set_dma_ seems bulletproof, same for kfree.


I must admit I have no idea why we have a reference to DMAs here, this looks
like an abuse to store a dai-specific context, and the initial test looks
like copy-paste to detect invalid configs, as done in other callbacks. Vinod
and Sanyog might have more history than me here.


I dont see snd_soc_dai_set_dma_data() call for
sdw_cdns_dma_data so somthing is missing (at least in upstream code)

IIRC we should have a snd_soc_dai_set_dma_data() in alloc or some
initialization routine and we free it here.. Sanyog?


Vinod, I double-checked that we do not indeed have a call to
snd_soc_dai_dma_data(), but there is code in cdns_set_stream() that sets the
relevant dai->playback/capture_dma_data, see below

I am not a big fan of this code, touching the ASoC core internal fields
isn't a good idea in general.


IIRC as long as you stick to single link I do not see this required. The
question comes into picture when we have multi links as you would need
to allocate a soundwire stream and set that for all the sdw DAIs

So, what is the current model of soundwire stream, which entity allocates
that and do you still care about multi-link? is there any machine driver
with soundwire upstream yet?


yes, multi-link is definitively required and one of the main appeals of 
SoundWire. We have a platform with 2 amplifiers on separate links and 
they need to be synchronized and handled with the stream concept.


The tentative plan would be to move the stream allocation to the dailink 
.init (or equivalent), and make sure each DAI in that link used the same 
stream information. There are dependencies on the multi-cpu concept that 
Morimoto-san wanted to push, so we'll likely be the first users.


For the DAI trigger, we will need to change the existing API so that a 
sdw_stream_enable() can be called multiple times, but only takes effect 
when the .trigger of the first DAI in the stream is invoked. This is a 
similar behavior than with HDaudio .trigger operations when the SYNC 
bits are used.


We will do this when we have a first pass working with all codec drivers 
upstream and a basic machine driver upstream with all 4 links working 
independently.


Everything is done in public btw, you can track our WIP solutions here:

https://github.com/thesofproject/linux/pull/1140
https://github.com/thesofproject/linux/pull/1141
https://github.com/thesofproject/linux/pull/1142



Re: [alsa-devel] [RFC PATCH 31/40] soundwire: intel: move shutdown() callback and don't export symbol

2019-08-23 Thread Vinod Koul
On 14-08-19, 14:31, Pierre-Louis Bossart wrote:
> 
> 
> > > > > +void intel_shutdown(struct snd_pcm_substream *substream,
> > > > > +    struct snd_soc_dai *dai)
> > > > > +{
> > > > > +    struct sdw_cdns_dma_data *dma;
> > > > > +
> > > > > +    dma = snd_soc_dai_get_dma_data(dai, substream);
> > > > > +    if (!dma)
> > > > > +    return;
> > > > > +
> > > > > +    snd_soc_dai_set_dma_data(dai, substream, NULL);
> > > > > +    kfree(dma);
> > > > > +}
> > > > 
> > > > Correct me if I'm wrong, but do we really need to _get_dma_ here?
> > > > _set_dma_ seems bulletproof, same for kfree.
> > > 
> > > I must admit I have no idea why we have a reference to DMAs here, this 
> > > looks
> > > like an abuse to store a dai-specific context, and the initial test looks
> > > like copy-paste to detect invalid configs, as done in other callbacks. 
> > > Vinod
> > > and Sanyog might have more history than me here.
> > 
> > I dont see snd_soc_dai_set_dma_data() call for
> > sdw_cdns_dma_data so somthing is missing (at least in upstream code)
> > 
> > IIRC we should have a snd_soc_dai_set_dma_data() in alloc or some
> > initialization routine and we free it here.. Sanyog?
> 
> Vinod, I double-checked that we do not indeed have a call to
> snd_soc_dai_dma_data(), but there is code in cdns_set_stream() that sets the
> relevant dai->playback/capture_dma_data, see below
> 
> I am not a big fan of this code, touching the ASoC core internal fields
> isn't a good idea in general.

IIRC as long as you stick to single link I do not see this required. The
question comes into picture when we have multi links as you would need
to allocate a soundwire stream and set that for all the sdw DAIs

So, what is the current model of soundwire stream, which entity allocates
that and do you still care about multi-link? is there any machine driver
with soundwire upstream yet?

> Also not sure why for a DAI we need both _drvdata and _dma_data (especially

_drvdata is global for driver whereas _dma_data is typically used per
DAI

> for this case where the information stored has absolutely nothing to do with
> DMAs).
> 
> If the idea was to keep a context that is direction-dependent, that's likely
> unnecessary. For the Intel/Cadence case the interfaces can be configured as
> playback OR capture, not both concurrently, so the "dma" information could
> have been stored in the generic DAI _drvdata.
> 
> I have other things to look into for now but this code will likely need to
> be cleaned-up at some point to remove unnecessary parts.

Sure please go ahead and do the cleanup.
> 
> int cdns_set_sdw_stream(struct snd_soc_dai *dai,
>   void *stream, bool pcm, int direction)
> {
>   struct sdw_cdns *cdns = snd_soc_dai_get_drvdata(dai);
>   struct sdw_cdns_dma_data *dma;
> 
>   dma = kzalloc(sizeof(*dma), GFP_KERNEL);
>   if (!dma)
>   return -ENOMEM;
> 
>   if (pcm)
>   dma->stream_type = SDW_STREAM_PCM;
>   else
>   dma->stream_type = SDW_STREAM_PDM;
> 
>   dma->bus = &cdns->bus;
>   dma->link_id = cdns->instance;
> 
>   dma->stream = stream;
> 
> >>> this is equivalent to snd_soc_dai_dma_data()
> 
>   if (direction == SNDRV_PCM_STREAM_PLAYBACK)
>   dai->playback_dma_data = dma;
>   else
>   dai->capture_dma_data = dma;
> 
>   return 0;
> }
> EXPORT_SYMBOL(cdns_set_sdw_stream);

-- 
~Vinod


Re: [alsa-devel] [RFC PATCH 31/40] soundwire: intel: move shutdown() callback and don't export symbol

2019-08-14 Thread Pierre-Louis Bossart





+void intel_shutdown(struct snd_pcm_substream *substream,
+    struct snd_soc_dai *dai)
+{
+    struct sdw_cdns_dma_data *dma;
+
+    dma = snd_soc_dai_get_dma_data(dai, substream);
+    if (!dma)
+    return;
+
+    snd_soc_dai_set_dma_data(dai, substream, NULL);
+    kfree(dma);
+}


Correct me if I'm wrong, but do we really need to _get_dma_ here?
_set_dma_ seems bulletproof, same for kfree.


I must admit I have no idea why we have a reference to DMAs here, this looks
like an abuse to store a dai-specific context, and the initial test looks
like copy-paste to detect invalid configs, as done in other callbacks. Vinod
and Sanyog might have more history than me here.


I dont see snd_soc_dai_set_dma_data() call for
sdw_cdns_dma_data so somthing is missing (at least in upstream code)

IIRC we should have a snd_soc_dai_set_dma_data() in alloc or some
initialization routine and we free it here.. Sanyog?


Vinod, I double-checked that we do not indeed have a call to 
snd_soc_dai_dma_data(), but there is code in cdns_set_stream() that sets 
the relevant dai->playback/capture_dma_data, see below


I am not a big fan of this code, touching the ASoC core internal fields 
isn't a good idea in general.


Also not sure why for a DAI we need both _drvdata and _dma_data 
(especially for this case where the information stored has absolutely 
nothing to do with DMAs).


If the idea was to keep a context that is direction-dependent, that's 
likely unnecessary. For the Intel/Cadence case the interfaces can be 
configured as playback OR capture, not both concurrently, so the "dma" 
information could have been stored in the generic DAI _drvdata.


I have other things to look into for now but this code will likely need 
to be cleaned-up at some point to remove unnecessary parts.


int cdns_set_sdw_stream(struct snd_soc_dai *dai,
void *stream, bool pcm, int direction)
{
struct sdw_cdns *cdns = snd_soc_dai_get_drvdata(dai);
struct sdw_cdns_dma_data *dma;

dma = kzalloc(sizeof(*dma), GFP_KERNEL);
if (!dma)
return -ENOMEM;

if (pcm)
dma->stream_type = SDW_STREAM_PCM;
else
dma->stream_type = SDW_STREAM_PDM;

dma->bus = &cdns->bus;
dma->link_id = cdns->instance;

dma->stream = stream;

>>> this is equivalent to snd_soc_dai_dma_data()

if (direction == SNDRV_PCM_STREAM_PLAYBACK)
dai->playback_dma_data = dma;
else
dai->capture_dma_data = dma;

return 0;
}
EXPORT_SYMBOL(cdns_set_sdw_stream);


Re: [alsa-devel] [RFC PATCH 31/40] soundwire: intel: move shutdown() callback and don't export symbol

2019-08-02 Thread Pierre-Louis Bossart

On 8/2/19 12:28 PM, Vinod Koul wrote:

On 26-07-19, 09:46, Pierre-Louis Bossart wrote:



On 7/26/19 5:38 AM, Cezary Rojewski wrote:

On 2019-07-26 01:40, Pierre-Louis Bossart wrote:

+void intel_shutdown(struct snd_pcm_substream *substream,
+    struct snd_soc_dai *dai)
+{
+    struct sdw_cdns_dma_data *dma;
+
+    dma = snd_soc_dai_get_dma_data(dai, substream);
+    if (!dma)
+    return;
+
+    snd_soc_dai_set_dma_data(dai, substream, NULL);
+    kfree(dma);
+}


Correct me if I'm wrong, but do we really need to _get_dma_ here?
_set_dma_ seems bulletproof, same for kfree.


I must admit I have no idea why we have a reference to DMAs here, this looks
like an abuse to store a dai-specific context, and the initial test looks
like copy-paste to detect invalid configs, as done in other callbacks. Vinod
and Sanyog might have more history than me here.


I dont see snd_soc_dai_set_dma_data() call for
sdw_cdns_dma_data so somthing is missing (at least in upstream code)

IIRC we should have a snd_soc_dai_set_dma_data() in alloc or some
initialization routine and we free it here.. Sanyog?


the code does a bunch of get_dma_data() and this seems to work, but 
indeed I don't see where the _set_dma_data() is done. magic.




Re: [alsa-devel] [RFC PATCH 31/40] soundwire: intel: move shutdown() callback and don't export symbol

2019-08-02 Thread Vinod Koul
On 26-07-19, 09:46, Pierre-Louis Bossart wrote:
> 
> 
> On 7/26/19 5:38 AM, Cezary Rojewski wrote:
> > On 2019-07-26 01:40, Pierre-Louis Bossart wrote:
> > > +void intel_shutdown(struct snd_pcm_substream *substream,
> > > +    struct snd_soc_dai *dai)
> > > +{
> > > +    struct sdw_cdns_dma_data *dma;
> > > +
> > > +    dma = snd_soc_dai_get_dma_data(dai, substream);
> > > +    if (!dma)
> > > +    return;
> > > +
> > > +    snd_soc_dai_set_dma_data(dai, substream, NULL);
> > > +    kfree(dma);
> > > +}
> > 
> > Correct me if I'm wrong, but do we really need to _get_dma_ here?
> > _set_dma_ seems bulletproof, same for kfree.
> 
> I must admit I have no idea why we have a reference to DMAs here, this looks
> like an abuse to store a dai-specific context, and the initial test looks
> like copy-paste to detect invalid configs, as done in other callbacks. Vinod
> and Sanyog might have more history than me here.

I dont see snd_soc_dai_set_dma_data() call for
sdw_cdns_dma_data so somthing is missing (at least in upstream code)

IIRC we should have a snd_soc_dai_set_dma_data() in alloc or some
initialization routine and we free it here.. Sanyog?

-- 
~Vinod


Re: [alsa-devel] [RFC PATCH 31/40] soundwire: intel: move shutdown() callback and don't export symbol

2019-07-26 Thread Pierre-Louis Bossart




On 7/26/19 5:38 AM, Cezary Rojewski wrote:

On 2019-07-26 01:40, Pierre-Louis Bossart wrote:

+void intel_shutdown(struct snd_pcm_substream *substream,
+    struct snd_soc_dai *dai)
+{
+    struct sdw_cdns_dma_data *dma;
+
+    dma = snd_soc_dai_get_dma_data(dai, substream);
+    if (!dma)
+    return;
+
+    snd_soc_dai_set_dma_data(dai, substream, NULL);
+    kfree(dma);
+}


Correct me if I'm wrong, but do we really need to _get_dma_ here?
_set_dma_ seems bulletproof, same for kfree.


I must admit I have no idea why we have a reference to DMAs here, this 
looks like an abuse to store a dai-specific context, and the initial 
test looks like copy-paste to detect invalid configs, as done in other 
callbacks. Vinod and Sanyog might have more history than me here.