diff mbox series

[1/3] ASoC: atmel-pdc: Use managed DMA buffer allocation

Message ID 20210106133650.13509-1-lars@metafoo.de (mailing list archive)
State Accepted
Commit 22eee4d3efe370fedf71ee6a9e4dead3f32ad461
Headers show
Series [1/3] ASoC: atmel-pdc: Use managed DMA buffer allocation | expand

Commit Message

Lars-Peter Clausen Jan. 6, 2021, 1:36 p.m. UTC
Instead of manually managing its DMA buffers using
dma_{alloc,free}_coherent() lets the sound core take care of this using
managed buffers.

On one hand this reduces the amount of boiler plate code, but the main
motivation for the change is to use the shared code where possible. This
makes it easier to argue about correctness and that the code does not
contain subtle bugs like data leakage or similar.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
---
 sound/soc/atmel/atmel-pcm-pdc.c | 78 ++-------------------------------
 1 file changed, 4 insertions(+), 74 deletions(-)

Comments

Codrin Ciubotariu Jan. 6, 2021, 5:27 p.m. UTC | #1
On 06.01.2021 15:36, Lars-Peter Clausen wrote:
> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> 
> Instead of manually managing its DMA buffers using
> dma_{alloc,free}_coherent() lets the sound core take care of this using
> managed buffers.
> 
> On one hand this reduces the amount of boiler plate code, but the main
> motivation for the change is to use the shared code where possible. This
> makes it easier to argue about correctness and that the code does not
> contain subtle bugs like data leakage or similar.
> 
> Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>

Reviewed-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com>

Thanks!
Mark Brown Jan. 13, 2021, 3:26 p.m. UTC | #2
On Wed, 6 Jan 2021 14:36:48 +0100, Lars-Peter Clausen wrote:
> Instead of manually managing its DMA buffers using
> dma_{alloc,free}_coherent() lets the sound core take care of this using
> managed buffers.
> 
> On one hand this reduces the amount of boiler plate code, but the main
> motivation for the change is to use the shared code where possible. This
> makes it easier to argue about correctness and that the code does not
> contain subtle bugs like data leakage or similar.

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git for-next

Thanks!

[1/3] ASoC: atmel-pdc: Use managed DMA buffer allocation
      commit: 22eee4d3efe370fedf71ee6a9e4dead3f32ad461
[2/3] ASoC: bcm: cygnus: Use managed DMA buffer allocation
      commit: 5ac813c83483e97a13b59aab34b89cebf9d5dcb8
[3/3] ASoC: kirkwood: Use managed DMA buffer allocation
      commit: b3c0ae75f5d3efa40174230b8c9c01848e03d4d0

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark
diff mbox series

Patch

diff --git a/sound/soc/atmel/atmel-pcm-pdc.c b/sound/soc/atmel/atmel-pcm-pdc.c
index 704f700013d3..3e7ea2021b46 100644
--- a/sound/soc/atmel/atmel-pcm-pdc.c
+++ b/sound/soc/atmel/atmel-pcm-pdc.c
@@ -34,86 +34,21 @@ 
 #include "atmel-pcm.h"
 
 
-static int atmel_pcm_preallocate_dma_buffer(struct snd_pcm *pcm,
-	int stream)
-{
-	struct snd_pcm_substream *substream = pcm->streams[stream].substream;
-	struct snd_dma_buffer *buf = &substream->dma_buffer;
-	size_t size = ATMEL_SSC_DMABUF_SIZE;
-
-	buf->dev.type = SNDRV_DMA_TYPE_DEV;
-	buf->dev.dev = pcm->card->dev;
-	buf->private_data = NULL;
-	buf->area = dma_alloc_coherent(pcm->card->dev, size,
-			&buf->addr, GFP_KERNEL);
-	pr_debug("atmel-pcm: alloc dma buffer: area=%p, addr=%p, size=%zu\n",
-			(void *)buf->area, (void *)(long)buf->addr, size);
-
-	if (!buf->area)
-		return -ENOMEM;
-
-	buf->bytes = size;
-	return 0;
-}
-
-static int atmel_pcm_mmap(struct snd_soc_component *component,
-			  struct snd_pcm_substream *substream,
-			  struct vm_area_struct *vma)
-{
-	return remap_pfn_range(vma, vma->vm_start,
-		       substream->dma_buffer.addr >> PAGE_SHIFT,
-		       vma->vm_end - vma->vm_start, vma->vm_page_prot);
-}
-
 static int atmel_pcm_new(struct snd_soc_component *component,
 			 struct snd_soc_pcm_runtime *rtd)
 {
 	struct snd_card *card = rtd->card->snd_card;
-	struct snd_pcm *pcm = rtd->pcm;
 	int ret;
 
 	ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
 	if (ret)
 		return ret;
 
-	if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
-		pr_debug("atmel-pcm: allocating PCM playback DMA buffer\n");
-		ret = atmel_pcm_preallocate_dma_buffer(pcm,
-			SNDRV_PCM_STREAM_PLAYBACK);
-		if (ret)
-			goto out;
-	}
+	snd_pcm_set_managed_buffer_all(rtd->pcm, SNDRV_DMA_TYPE_DEV,
+				       card->dev, ATMEL_SSC_DMABUF_SIZE,
+				       ATMEL_SSC_DMABUF_SIZE);
 
-	if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) {
-		pr_debug("atmel-pcm: allocating PCM capture DMA buffer\n");
-		ret = atmel_pcm_preallocate_dma_buffer(pcm,
-			SNDRV_PCM_STREAM_CAPTURE);
-		if (ret)
-			goto out;
-	}
- out:
-	return ret;
-}
-
-static void atmel_pcm_free(struct snd_soc_component *component,
-			   struct snd_pcm *pcm)
-{
-	struct snd_pcm_substream *substream;
-	struct snd_dma_buffer *buf;
-	int stream;
-
-	for (stream = 0; stream < 2; stream++) {
-		substream = pcm->streams[stream].substream;
-		if (!substream)
-			continue;
-
-		buf = &substream->dma_buffer;
-		if (!buf->area)
-			continue;
-		dma_free_coherent(pcm->card->dev, buf->bytes,
-				  buf->area, buf->addr);
-		buf->area = NULL;
-	}
+	return 0;
 }
 
 /*--------------------------------------------------------------------------*\
@@ -210,9 +145,6 @@  static int atmel_pcm_hw_params(struct snd_soc_component *component,
 	/* this may get called several times by oss emulation
 	 * with different params */
 
-	snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
-	runtime->dma_bytes = params_buffer_bytes(params);
-
 	prtd->params = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), substream);
 	prtd->params->dma_intr_handler = atmel_pcm_dma_irq;
 
@@ -384,9 +316,7 @@  static const struct snd_soc_component_driver atmel_soc_platform = {
 	.prepare	= atmel_pcm_prepare,
 	.trigger	= atmel_pcm_trigger,
 	.pointer	= atmel_pcm_pointer,
-	.mmap		= atmel_pcm_mmap,
 	.pcm_construct	= atmel_pcm_new,
-	.pcm_destruct	= atmel_pcm_free,
 };
 
 int atmel_pcm_pdc_platform_register(struct device *dev)