Re: [PATCH v2] b43: Replace mdelay with usleep_range in b43_radio_2057_init_post

[Larry Finger]

On 01/08/2018 07:40 PM, Jia-Ju Bai wrote:

b43_radio_2057_init_post is not called in an interrupt handler
nor holding a spinlock.
The function mdelay in it can be replaced with usleep_range,
to reduce busy wait.

Signed-off-by: Jia-Ju Bai 
---
v2:
* Replace mdelay with usleep_range, instead of msleep in v1.
   Thank Larry for good advice.
---


I agree that a sleep of 2-3 ms should be OK here.

Acked-by: Larry Finger 

Larry


  drivers/net/wireless/broadcom/b43/phy_n.c |2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/broadcom/b43/phy_n.c 
b/drivers/net/wireless/broadcom/b43/phy_n.c
index a5557d7..f2a2f41 100644
--- a/drivers/net/wireless/broadcom/b43/phy_n.c
+++ b/drivers/net/wireless/broadcom/b43/phy_n.c
@@ -1031,7 +1031,7 @@ static void b43_radio_2057_init_post(struct b43_wldev 
*dev)
  
  	b43_radio_set(dev, R2057_RFPLL_MISC_CAL_RESETN, 0x78);

b43_radio_set(dev, R2057_XTAL_CONFIG2, 0x80);
-   mdelay(2);
+   usleep_range(2000, 3000);
b43_radio_mask(dev, R2057_RFPLL_MISC_CAL_RESETN, ~0x78);
b43_radio_mask(dev, R2057_XTAL_CONFIG2, ~0x80);
  

Re: [PATCH v2] b43: Replace mdelay with usleep_range in b43_radio_2057_init_post

[Arend van Spriel]

On 1/9/2018 10:47 AM, Jia-Ju Bai wrote:



On 2018/1/9 17:07, Arend van Spriel wrote:

On 1/9/2018 9:39 AM, Jia-Ju Bai wrote:



On 2018/1/9 16:35, Greg KH wrote:

On Tue, Jan 09, 2018 at 09:40:06AM +0800, Jia-Ju Bai wrote:

b43_radio_2057_init_post is not called in an interrupt handler
nor holding a spinlock.
The function mdelay in it can be replaced with usleep_range,
to reduce busy wait.

Signed-off-by: Jia-Ju Bai 
---
v2:
* Replace mdelay with usleep_range, instead of msleep in v1.
   Thank Larry for good advice.
---
  drivers/net/wireless/broadcom/b43/phy_n.c |2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/broadcom/b43/phy_n.c
b/drivers/net/wireless/broadcom/b43/phy_n.c
index a5557d7..f2a2f41 100644
--- a/drivers/net/wireless/broadcom/b43/phy_n.c
+++ b/drivers/net/wireless/broadcom/b43/phy_n.c
@@ -1031,7 +1031,7 @@ static void b43_radio_2057_init_post(struct
b43_wldev *dev)
  b43_radio_set(dev, R2057_RFPLL_MISC_CAL_RESETN, 0x78);
  b43_radio_set(dev, R2057_XTAL_CONFIG2, 0x80);
-mdelay(2);
+usleep_range(2000, 3000);

Where did 3000 come from?  Are you sure about that?


I am not very sure, and I use it according to Larry's message:


Hi Jia-Ju Bai,

The duration here is for settling the registers so hardware can pick
it up. Right after this they are written again. Now this is during
initialization of the radio so not time critical, but probably
anything in the range of 2000..3000 would also have been fine.


Hi Arend,

Thanks for your detailed explanation :)
So I think usleep_range(2000, 3000) is okay.


Sure.

Regards,
Arend

Re: [PATCH v2] b43: Replace mdelay with usleep_range in b43_radio_2057_init_post

[Jia-Ju Bai]

On 2018/1/9 17:07, Arend van Spriel wrote:

On 1/9/2018 9:39 AM, Jia-Ju Bai wrote:



On 2018/1/9 16:35, Greg KH wrote:

On Tue, Jan 09, 2018 at 09:40:06AM +0800, Jia-Ju Bai wrote:

b43_radio_2057_init_post is not called in an interrupt handler
nor holding a spinlock.
The function mdelay in it can be replaced with usleep_range,
to reduce busy wait.

Signed-off-by: Jia-Ju Bai 
---
v2:
* Replace mdelay with usleep_range, instead of msleep in v1.
   Thank Larry for good advice.
---
  drivers/net/wireless/broadcom/b43/phy_n.c |2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/broadcom/b43/phy_n.c
b/drivers/net/wireless/broadcom/b43/phy_n.c
index a5557d7..f2a2f41 100644
--- a/drivers/net/wireless/broadcom/b43/phy_n.c
+++ b/drivers/net/wireless/broadcom/b43/phy_n.c
@@ -1031,7 +1031,7 @@ static void b43_radio_2057_init_post(struct
b43_wldev *dev)
  b43_radio_set(dev, R2057_RFPLL_MISC_CAL_RESETN, 0x78);
  b43_radio_set(dev, R2057_XTAL_CONFIG2, 0x80);
-mdelay(2);
+usleep_range(2000, 3000);

Where did 3000 come from?  Are you sure about that?


I am not very sure, and I use it according to Larry's message:


Hi Jia-Ju Bai,

The duration here is for settling the registers so hardware can pick 
it up. Right after this they are written again. Now this is during 
initialization of the radio so not time critical, but probably 
anything in the range of 2000..3000 would also have been fine.


Hi Arend,

Thanks for your detailed explanation :)
So I think usleep_range(2000, 3000) is okay.


Thanks,
Jia-Ju Bai

Re: [PATCH v2] b43: Replace mdelay with usleep_range in b43_radio_2057_init_post

[Arend van Spriel]

On 1/9/2018 9:39 AM, Jia-Ju Bai wrote:



On 2018/1/9 16:35, Greg KH wrote:

On Tue, Jan 09, 2018 at 09:40:06AM +0800, Jia-Ju Bai wrote:

b43_radio_2057_init_post is not called in an interrupt handler
nor holding a spinlock.
The function mdelay in it can be replaced with usleep_range,
to reduce busy wait.

Signed-off-by: Jia-Ju Bai 
---
v2:
* Replace mdelay with usleep_range, instead of msleep in v1.
   Thank Larry for good advice.
---
  drivers/net/wireless/broadcom/b43/phy_n.c |2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/broadcom/b43/phy_n.c
b/drivers/net/wireless/broadcom/b43/phy_n.c
index a5557d7..f2a2f41 100644
--- a/drivers/net/wireless/broadcom/b43/phy_n.c
+++ b/drivers/net/wireless/broadcom/b43/phy_n.c
@@ -1031,7 +1031,7 @@ static void b43_radio_2057_init_post(struct
b43_wldev *dev)
  b43_radio_set(dev, R2057_RFPLL_MISC_CAL_RESETN, 0x78);
  b43_radio_set(dev, R2057_XTAL_CONFIG2, 0x80);
-mdelay(2);
+usleep_range(2000, 3000);

Where did 3000 come from?  Are you sure about that?


I am not very sure, and I use it according to Larry's message:


Hi Jia-Ju Bai,

The duration here is for settling the registers so hardware can pick it 
up. Right after this they are written again. Now this is during 
initialization of the radio so not time critical, but probably anything 
in the range of 2000..3000 would also have been fine.


Regards,
Arend

Re: [PATCH v2] b43: Replace mdelay with usleep_range in b43_radio_2057_init_post

[Jia-Ju Bai]

On 2018/1/9 16:35, Greg KH wrote:

On Tue, Jan 09, 2018 at 09:40:06AM +0800, Jia-Ju Bai wrote:

b43_radio_2057_init_post is not called in an interrupt handler
nor holding a spinlock.
The function mdelay in it can be replaced with usleep_range,
to reduce busy wait.

Signed-off-by: Jia-Ju Bai 
---
v2:
* Replace mdelay with usleep_range, instead of msleep in v1.
   Thank Larry for good advice.
---
  drivers/net/wireless/broadcom/b43/phy_n.c |2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/broadcom/b43/phy_n.c 
b/drivers/net/wireless/broadcom/b43/phy_n.c
index a5557d7..f2a2f41 100644
--- a/drivers/net/wireless/broadcom/b43/phy_n.c
+++ b/drivers/net/wireless/broadcom/b43/phy_n.c
@@ -1031,7 +1031,7 @@ static void b43_radio_2057_init_post(struct b43_wldev 
*dev)
  
  	b43_radio_set(dev, R2057_RFPLL_MISC_CAL_RESETN, 0x78);

b43_radio_set(dev, R2057_XTAL_CONFIG2, 0x80);
-   mdelay(2);
+   usleep_range(2000, 3000);

Where did 3000 come from?  Are you sure about that?


I am not very sure, and I use it according to Larry's message:


I had negative comments on one of those due to the possibility of
msleep(2) extending as long as 20 msec. Until the author, or someone
else, can test that this is OK, then the mdelay(2) can only be
replaced with usleep_range(2000, 3000).


Thanks,
Jia-Ju Bai

Re: [PATCH v2] b43: Replace mdelay with usleep_range in b43_radio_2057_init_post

[Greg KH]

On Tue, Jan 09, 2018 at 09:40:06AM +0800, Jia-Ju Bai wrote:
> b43_radio_2057_init_post is not called in an interrupt handler
> nor holding a spinlock.
> The function mdelay in it can be replaced with usleep_range, 
> to reduce busy wait.
> 
> Signed-off-by: Jia-Ju Bai 
> ---
> v2:
> * Replace mdelay with usleep_range, instead of msleep in v1.
>   Thank Larry for good advice.
> ---
>  drivers/net/wireless/broadcom/b43/phy_n.c |2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/wireless/broadcom/b43/phy_n.c 
> b/drivers/net/wireless/broadcom/b43/phy_n.c
> index a5557d7..f2a2f41 100644
> --- a/drivers/net/wireless/broadcom/b43/phy_n.c
> +++ b/drivers/net/wireless/broadcom/b43/phy_n.c
> @@ -1031,7 +1031,7 @@ static void b43_radio_2057_init_post(struct b43_wldev 
> *dev)
>  
>   b43_radio_set(dev, R2057_RFPLL_MISC_CAL_RESETN, 0x78);
>   b43_radio_set(dev, R2057_XTAL_CONFIG2, 0x80);
> - mdelay(2);
> + usleep_range(2000, 3000);

Where did 3000 come from?  Are you sure about that?

thanks,

greg k-h

[PATCH v2] b43: Replace mdelay with usleep_range in b43_radio_2057_init_post

[Jia-Ju Bai]

b43_radio_2057_init_post is not called in an interrupt handler
nor holding a spinlock.
The function mdelay in it can be replaced with usleep_range, 
to reduce busy wait.

Signed-off-by: Jia-Ju Bai 
---
v2:
* Replace mdelay with usleep_range, instead of msleep in v1.
  Thank Larry for good advice.
---
 drivers/net/wireless/broadcom/b43/phy_n.c |2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/broadcom/b43/phy_n.c 
b/drivers/net/wireless/broadcom/b43/phy_n.c
index a5557d7..f2a2f41 100644
--- a/drivers/net/wireless/broadcom/b43/phy_n.c
+++ b/drivers/net/wireless/broadcom/b43/phy_n.c
@@ -1031,7 +1031,7 @@ static void b43_radio_2057_init_post(struct b43_wldev 
*dev)
 
b43_radio_set(dev, R2057_RFPLL_MISC_CAL_RESETN, 0x78);
b43_radio_set(dev, R2057_XTAL_CONFIG2, 0x80);
-   mdelay(2);
+   usleep_range(2000, 3000);
b43_radio_mask(dev, R2057_RFPLL_MISC_CAL_RESETN, ~0x78);
b43_radio_mask(dev, R2057_XTAL_CONFIG2, ~0x80);
 
-- 
1.7.9.5