diff mbox

[v2,2/4] ASoC: Drop SND_DMAENGINE_PCM_FLAG_CUSTOM_CHANNEL_NAME flag

Message ID 1477408121-24716-2-git-send-email-s.nawrocki@samsung.com (mailing list archive)
State New, archived
Headers show

Commit Message

Sylwester Nawrocki/Kernel \(PLT\) /SRPOL/Staff Engineer/Samsung Electronics Oct. 25, 2016, 3:08 p.m. UTC 
Since commit 194c7dea00c68c1b1f8ff26304fa937a006f66dd
"ASoC: dmaengine: add custom DMA config to snd_dmaengine_pcm_config"
custom DMA channels can be also specified in chan_names[] field of
struct snd_dmaengine_pcm_config.  This patch removes chan_name field
of struct snd_dmaengine_dai_dma_data as it is now unused.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
---
Changes since v1:
 - the framework code changes put in a separate (this) patch.

 include/sound/dmaengine_pcm.h         |  6 ------
 sound/soc/soc-generic-dmaengine-pcm.c | 13 +------------
 2 files changed, 1 insertion(+), 18 deletions(-)

--
1.9.1

Comments

Lars-Peter Clausen Oct. 25, 2016, 4:28 p.m. UTC | #1 
On 10/25/2016 05:08 PM, Sylwester Nawrocki wrote:
> Since commit 194c7dea00c68c1b1f8ff26304fa937a006f66dd
> "ASoC: dmaengine: add custom DMA config to snd_dmaengine_pcm_config"
> custom DMA channels can be also specified in chan_names[] field of
> struct snd_dmaengine_pcm_config.  This patch removes chan_name field
> of struct snd_dmaengine_dai_dma_data as it is now unused.
> 
> Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>

Acked-by: Lars-Peter Clausen <lars@metafoo.de>

Thanks.
Sylwester Nawrocki/Kernel \(PLT\) /SRPOL/Staff Engineer/Samsung Electronics Oct. 27, 2016, 11:21 a.m. UTC | #2 
On 10/25/2016 05:08 PM, Sylwester Nawrocki wrote:
> Since commit 194c7dea00c68c1b1f8ff26304fa937a006f66dd
> "ASoC: dmaengine: add custom DMA config to snd_dmaengine_pcm_config"
> custom DMA channels can be also specified in chan_names[] field of
> struct snd_dmaengine_pcm_config.  This patch removes chan_name field
> of struct snd_dmaengine_dai_dma_data as it is now unused.
> 
> Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>

I'm afraid this patch needs to be reverted :/ I didn't notice earlier
the Samsung AC97 controller has 3 substreams per a platform device and
this cannot be handled with struct snd_dmaengine_pcm_config, which
allows to specify up to 2 DMA channel names.

The AC97 driver (sound/soc/samsung/ac97.c) seems to have been broken
for a long time as it currently doesn't have the channel names
specified at all [1].  It seems in order to fix it the best would
be to restore the feature the $subject patch removes.

[1]
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/sound/soc/samsung/ac97.c#n40

>  include/sound/dmaengine_pcm.h         |  6 ------
>  sound/soc/soc-generic-dmaengine-pcm.c | 13 +------------
>  2 files changed, 1 insertion(+), 18 deletions(-)
> 
> diff --git a/include/sound/dmaengine_pcm.h b/include/sound/dmaengine_pcm.h
> index 67be244..1c8f9e1 100644
> --- a/include/sound/dmaengine_pcm.h
> +++ b/include/sound/dmaengine_pcm.h
> @@ -71,7 +71,6 @@ struct dma_chan *snd_dmaengine_pcm_request_channel(dma_filter_fn filter_fn,
>   * @slave_id: Slave requester id for the DMA channel.
>   * @filter_data: Custom DMA channel filter data, this will usually be used when
>   * requesting the DMA channel.
> - * @chan_name: Custom channel name to use when requesting DMA channel.
>   * @fifo_size: FIFO size of the DAI controller in bytes
>   * @flags: PCM_DAI flags, only SND_DMAENGINE_PCM_DAI_FLAG_PACK for now
>   */
> @@ -81,7 +80,6 @@ struct snd_dmaengine_dai_dma_data {
>  	u32 maxburst;
>  	unsigned int slave_id;
>  	void *filter_data;
> -	const char *chan_name;
>  	unsigned int fifo_size;
>  	unsigned int flags;
>  };
> @@ -107,10 +105,6 @@ void snd_dmaengine_pcm_set_config_from_dai_data(
>   * playback.
>   */
>  #define SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX BIT(3)
> -/*
> - * The PCM streams have custom channel names specified.
> - */
> -#define SND_DMAENGINE_PCM_FLAG_CUSTOM_CHANNEL_NAME BIT(4)
> 
>  /**
>   * struct snd_dmaengine_pcm_config - Configuration data for dmaengine based PCM
> diff --git a/sound/soc/soc-generic-dmaengine-pcm.c b/sound/soc/soc-generic-dmaengine-pcm.c
> index 6cef397..17eb149 100644
> --- a/sound/soc/soc-generic-dmaengine-pcm.c
> +++ b/sound/soc/soc-generic-dmaengine-pcm.c
> @@ -263,7 +263,6 @@ static int dmaengine_pcm_new(struct snd_soc_pcm_runtime *rtd)
>  	struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform);
>  	const struct snd_dmaengine_pcm_config *config = pcm->config;
>  	struct device *dev = rtd->platform->dev;
> -	struct snd_dmaengine_dai_dma_data *dma_data;
>  	struct snd_pcm_substream *substream;
>  	size_t prealloc_buffer_size;
>  	size_t max_buffer_size;
> @@ -278,19 +277,11 @@ static int dmaengine_pcm_new(struct snd_soc_pcm_runtime *rtd)
>  		max_buffer_size = SIZE_MAX;
>  	}
> 
> -
>  	for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE; i++) {
>  		substream = rtd->pcm->streams[i].substream;
>  		if (!substream)
>  			continue;
> 
> -		dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
> -
> -		if (!pcm->chan[i] &&
> -		    (pcm->flags & SND_DMAENGINE_PCM_FLAG_CUSTOM_CHANNEL_NAME))
> -			pcm->chan[i] = dma_request_slave_channel(dev,
> -				dma_data->chan_name);
> -
>  		if (!pcm->chan[i] && (pcm->flags & SND_DMAENGINE_PCM_FLAG_COMPAT)) {
>  			pcm->chan[i] = dmaengine_pcm_compat_request_channel(rtd,
>  				substream);
> @@ -359,9 +350,7 @@ static int dmaengine_pcm_request_chan_of(struct dmaengine_pcm *pcm,
>  	const char *name;
>  	struct dma_chan *chan;
> 
> -	if ((pcm->flags & (SND_DMAENGINE_PCM_FLAG_NO_DT |
> -			   SND_DMAENGINE_PCM_FLAG_CUSTOM_CHANNEL_NAME)) ||
> -	    !dev->of_node)
> +	if ((pcm->flags & SND_DMAENGINE_PCM_FLAG_NO_DT) || !dev->of_node)
>  		return 0;

I somehow messed up testing this patch series on a non-DT platform and
missed the fact that standard "tx", "rx" DMA channel names will only
be used for DT cases in the ASoC core.

Perhaps it makes sense to change the above test to something like:

 if (((pcm->flags & SND_DMAENGINE_PCM_FLAG_NO_DT) || (!dev->of_node &&
		     (pcm->flags & SND_DMAENGINE_PCM_FLAG_COMPAT))))
	return 0;

so when a platform gets converted to use the DMA slave map it can be
treated similarly to a DT platform when SND_DMAENGINE_PCM_FLAG_COMPAT
flag is not set.

I'd either need a change as above or to also revert patch 1/4 :/

>  	if (config && config->dma_dev) {
> --
> 1.9.1

--
Thanks,
Sylwester
Mark Brown Oct. 27, 2016, 2:23 p.m. UTC | #3 
On Thu, Oct 27, 2016 at 01:21:21PM +0200, Sylwester Nawrocki wrote:
> On 10/25/2016 05:08 PM, Sylwester Nawrocki wrote:
> > Since commit 194c7dea00c68c1b1f8ff26304fa937a006f66dd
> > "ASoC: dmaengine: add custom DMA config to snd_dmaengine_pcm_config"
> > custom DMA channels can be also specified in chan_names[] field of
> > struct snd_dmaengine_pcm_config.  This patch removes chan_name field
> > of struct snd_dmaengine_dai_dma_data as it is now unused.
> > 
> > Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
> 
> I'm afraid this patch needs to be reverted :/ I didn't notice earlier
> the Samsung AC97 controller has 3 substreams per a platform device and
> this cannot be handled with struct snd_dmaengine_pcm_config, which
> allows to specify up to 2 DMA channel names.

Can you send a revert patch with an explanation though...

> The AC97 driver (sound/soc/samsung/ac97.c) seems to have been broken
> for a long time as it currently doesn't have the channel names
> specified at all [1].  It seems in order to fix it the best would
> be to restore the feature the $subject patch removes.

...if the driver just doesn't work and hasn't worked for a long time
perhaps it's better to just drop the driver?
Sylwester Nawrocki/Kernel \(PLT\) /SRPOL/Staff Engineer/Samsung Electronics Oct. 27, 2016, 3:28 p.m. UTC | #4 
On 10/27/2016 04:23 PM, Mark Brown wrote:
> On Thu, Oct 27, 2016 at 01:21:21PM +0200, Sylwester Nawrocki wrote:
>> On 10/25/2016 05:08 PM, Sylwester Nawrocki wrote:
>>> Since commit 194c7dea00c68c1b1f8ff26304fa937a006f66dd
>>> "ASoC: dmaengine: add custom DMA config to snd_dmaengine_pcm_config"
>>> custom DMA channels can be also specified in chan_names[] field of
>>> struct snd_dmaengine_pcm_config.  This patch removes chan_name field
>>> of struct snd_dmaengine_dai_dma_data as it is now unused.
>>>
>>> Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
>>
>> I'm afraid this patch needs to be reverted :/ I didn't notice earlier
>> the Samsung AC97 controller has 3 substreams per a platform device and
>> this cannot be handled with struct snd_dmaengine_pcm_config, which
>> allows to specify up to 2 DMA channel names.
> 
> Can you send a revert patch with an explanation though...

Sure, I'll prepare the patch.

>> The AC97 driver (sound/soc/samsung/ac97.c) seems to have been broken
>> for a long time as it currently doesn't have the channel names
>> specified at all [1].  It seems in order to fix it the best would
>> be to restore the feature the $subject patch removes.
> 
> ...if the driver just doesn't work and hasn't worked for a long time
> perhaps it's better to just drop the driver?

I'm not opposed to that, the feature certainly hasn't been used for
a long time with mainline kernels.
Then I think these drivers could be dropped as well:

sound/soc/samsung/ln2440sbc_alc650.c
sound/soc/samsung/smdk2443_wm9710.c
sound/soc/samsung/smdk_wm9713.c

That all could be added again with support for new frameworks if there
are requests to support the feature.
I'm going to post patches removing those drivers.

Still I'd like to revert $subject patch to be able to handle more than
2 substreams per DMA device.  I planned to get rid of an additional
platform device creation in sound/soc/samsung/i2s.c,  which IIUC
introduces now unnecessary complication, could be avoided and doesn't
match the hardware very well.  Not quite sure it that would be
the right direction but I think being able to specify custom DMA channel
names per DAI DMA data could be helpful in doing that. I.e. to have
1 PCM with 3 substreams {"tx", "rx", "tx-sec"} instead of 2 PCMs with
substreams {"tx", "rx"} and {"tx-sec"}.

--
Thanks,
Sylwester
diff mbox

Patch

diff --git a/include/sound/dmaengine_pcm.h b/include/sound/dmaengine_pcm.h
index 67be244..1c8f9e1 100644
--- a/include/sound/dmaengine_pcm.h
+++ b/include/sound/dmaengine_pcm.h
@@ -71,7 +71,6 @@  struct dma_chan *snd_dmaengine_pcm_request_channel(dma_filter_fn filter_fn,
  * @slave_id: Slave requester id for the DMA channel.
  * @filter_data: Custom DMA channel filter data, this will usually be used when
  * requesting the DMA channel.
- * @chan_name: Custom channel name to use when requesting DMA channel.
  * @fifo_size: FIFO size of the DAI controller in bytes
  * @flags: PCM_DAI flags, only SND_DMAENGINE_PCM_DAI_FLAG_PACK for now
  */
@@ -81,7 +80,6 @@  struct snd_dmaengine_dai_dma_data {
 	u32 maxburst;
 	unsigned int slave_id;
 	void *filter_data;
-	const char *chan_name;
 	unsigned int fifo_size;
 	unsigned int flags;
 };
@@ -107,10 +105,6 @@  void snd_dmaengine_pcm_set_config_from_dai_data(
  * playback.
  */
 #define SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX BIT(3)
-/*
- * The PCM streams have custom channel names specified.
- */
-#define SND_DMAENGINE_PCM_FLAG_CUSTOM_CHANNEL_NAME BIT(4)

 /**
  * struct snd_dmaengine_pcm_config - Configuration data for dmaengine based PCM
diff --git a/sound/soc/soc-generic-dmaengine-pcm.c b/sound/soc/soc-generic-dmaengine-pcm.c
index 6cef397..17eb149 100644
--- a/sound/soc/soc-generic-dmaengine-pcm.c
+++ b/sound/soc/soc-generic-dmaengine-pcm.c
@@ -263,7 +263,6 @@  static int dmaengine_pcm_new(struct snd_soc_pcm_runtime *rtd)
 	struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform);
 	const struct snd_dmaengine_pcm_config *config = pcm->config;
 	struct device *dev = rtd->platform->dev;
-	struct snd_dmaengine_dai_dma_data *dma_data;
 	struct snd_pcm_substream *substream;
 	size_t prealloc_buffer_size;
 	size_t max_buffer_size;
@@ -278,19 +277,11 @@  static int dmaengine_pcm_new(struct snd_soc_pcm_runtime *rtd)
 		max_buffer_size = SIZE_MAX;
 	}

-
 	for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE; i++) {
 		substream = rtd->pcm->streams[i].substream;
 		if (!substream)
 			continue;

-		dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
-
-		if (!pcm->chan[i] &&
-		    (pcm->flags & SND_DMAENGINE_PCM_FLAG_CUSTOM_CHANNEL_NAME))
-			pcm->chan[i] = dma_request_slave_channel(dev,
-				dma_data->chan_name);
-
 		if (!pcm->chan[i] && (pcm->flags & SND_DMAENGINE_PCM_FLAG_COMPAT)) {
 			pcm->chan[i] = dmaengine_pcm_compat_request_channel(rtd,
 				substream);
@@ -359,9 +350,7 @@  static int dmaengine_pcm_request_chan_of(struct dmaengine_pcm *pcm,
 	const char *name;
 	struct dma_chan *chan;

-	if ((pcm->flags & (SND_DMAENGINE_PCM_FLAG_NO_DT |
-			   SND_DMAENGINE_PCM_FLAG_CUSTOM_CHANNEL_NAME)) ||
-	    !dev->of_node)
+	if ((pcm->flags & SND_DMAENGINE_PCM_FLAG_NO_DT) || !dev->of_node)
 		return 0;

 	if (config && config->dma_dev) {