136 lines
		
	
	
		
			4.2 KiB
		
	
	
	
		
			Diff
		
	
	
	
	
	
			
		
		
	
	
			136 lines
		
	
	
		
			4.2 KiB
		
	
	
	
		
			Diff
		
	
	
	
	
	
From 0b20c174a17dcfa805ddac1301a5af7298877ec3 Mon Sep 17 00:00:00 2001
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From: Lars-Peter Clausen <lars@metafoo.de>
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Date: Wed, 6 Jan 2021 14:36:48 +0100
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Subject: [PATCH 144/247] ASoC: atmel-pdc: Use managed DMA buffer allocation
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Instead of manually managing its DMA buffers using
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dma_{alloc,free}_coherent() lets the sound core take care of this using
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managed buffers.
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On one hand this reduces the amount of boiler plate code, but the main
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motivation for the change is to use the shared code where possible. This
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makes it easier to argue about correctness and that the code does not
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contain subtle bugs like data leakage or similar.
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Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
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Reviewed-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com>
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Link: https://lore.kernel.org/r/20210106133650.13509-1-lars@metafoo.de
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Signed-off-by: Mark Brown <broonie@kernel.org>
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---
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 sound/soc/atmel/atmel-pcm-pdc.c | 78 ++-------------------------------
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 1 file changed, 4 insertions(+), 74 deletions(-)
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--- a/sound/soc/atmel/atmel-pcm-pdc.c
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+++ b/sound/soc/atmel/atmel-pcm-pdc.c
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@@ -34,86 +34,21 @@
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 #include "atmel-pcm.h"
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-static int atmel_pcm_preallocate_dma_buffer(struct snd_pcm *pcm,
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-	int stream)
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-{
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-	struct snd_pcm_substream *substream = pcm->streams[stream].substream;
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-	struct snd_dma_buffer *buf = &substream->dma_buffer;
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-	size_t size = ATMEL_SSC_DMABUF_SIZE;
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-
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-	buf->dev.type = SNDRV_DMA_TYPE_DEV;
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-	buf->dev.dev = pcm->card->dev;
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-	buf->private_data = NULL;
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-	buf->area = dma_alloc_coherent(pcm->card->dev, size,
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-			&buf->addr, GFP_KERNEL);
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-	pr_debug("atmel-pcm: alloc dma buffer: area=%p, addr=%p, size=%zu\n",
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-			(void *)buf->area, (void *)(long)buf->addr, size);
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-
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-	if (!buf->area)
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-		return -ENOMEM;
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-
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-	buf->bytes = size;
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-	return 0;
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-}
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-
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-static int atmel_pcm_mmap(struct snd_soc_component *component,
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-			  struct snd_pcm_substream *substream,
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-			  struct vm_area_struct *vma)
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-{
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-	return remap_pfn_range(vma, vma->vm_start,
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-		       substream->dma_buffer.addr >> PAGE_SHIFT,
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-		       vma->vm_end - vma->vm_start, vma->vm_page_prot);
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-}
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-
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 static int atmel_pcm_new(struct snd_soc_component *component,
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 			 struct snd_soc_pcm_runtime *rtd)
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 {
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 	struct snd_card *card = rtd->card->snd_card;
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-	struct snd_pcm *pcm = rtd->pcm;
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 	int ret;
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 	ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
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 	if (ret)
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 		return ret;
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-	if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
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-		pr_debug("atmel-pcm: allocating PCM playback DMA buffer\n");
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-		ret = atmel_pcm_preallocate_dma_buffer(pcm,
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-			SNDRV_PCM_STREAM_PLAYBACK);
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-		if (ret)
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-			goto out;
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-	}
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+	snd_pcm_set_managed_buffer_all(rtd->pcm, SNDRV_DMA_TYPE_DEV,
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+				       card->dev, ATMEL_SSC_DMABUF_SIZE,
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+				       ATMEL_SSC_DMABUF_SIZE);
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-	if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) {
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-		pr_debug("atmel-pcm: allocating PCM capture DMA buffer\n");
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-		ret = atmel_pcm_preallocate_dma_buffer(pcm,
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-			SNDRV_PCM_STREAM_CAPTURE);
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-		if (ret)
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-			goto out;
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-	}
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- out:
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-	return ret;
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-}
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-
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-static void atmel_pcm_free(struct snd_soc_component *component,
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-			   struct snd_pcm *pcm)
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-{
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-	struct snd_pcm_substream *substream;
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-	struct snd_dma_buffer *buf;
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-	int stream;
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-
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-	for (stream = 0; stream < 2; stream++) {
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-		substream = pcm->streams[stream].substream;
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-		if (!substream)
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-			continue;
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-
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-		buf = &substream->dma_buffer;
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-		if (!buf->area)
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-			continue;
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-		dma_free_coherent(pcm->card->dev, buf->bytes,
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-				  buf->area, buf->addr);
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-		buf->area = NULL;
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-	}
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+	return 0;
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 }
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 /*--------------------------------------------------------------------------*\
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@@ -210,9 +145,6 @@ static int atmel_pcm_hw_params(struct sn
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 	/* this may get called several times by oss emulation
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 	 * with different params */
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-	snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
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-	runtime->dma_bytes = params_buffer_bytes(params);
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-
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 	prtd->params = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), substream);
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 	prtd->params->dma_intr_handler = atmel_pcm_dma_irq;
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@@ -384,9 +316,7 @@ static const struct snd_soc_component_dr
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 	.prepare	= atmel_pcm_prepare,
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 	.trigger	= atmel_pcm_trigger,
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 	.pointer	= atmel_pcm_pointer,
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-	.mmap		= atmel_pcm_mmap,
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 	.pcm_construct	= atmel_pcm_new,
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-	.pcm_destruct	= atmel_pcm_free,
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 };
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 int atmel_pcm_pdc_platform_register(struct device *dev)
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