MLK-18947: ASoC: imx-pcm-dma: alloc buffer from IRAM

In some platform, the low power audio playback should be
supported, which need the audio buffer allocated from
OCRAM/IRAM. So move the buffer allocation to .open
function at that time the dma chan is allocated.

Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
(cherry picked from commit 85c59acfc5c8d17aa0f369dbe30e4a5fb128c25f)

1 files changed, 39 insertions, 63 deletions

diff --git a/sound/soc/fsl/imx-pcm-dma-v2.c b/sound/soc/fsl/imx-pcm-dma-v2.c
index f8e89588b8e2..4c38efbbf907 100644
--- a/sound/soc/fsl/imx-pcm-dma-v2.c
+++ b/sound/soc/fsl/imx-pcm-dma-v2.c
@@ -99,6 +99,28 @@ static snd_pcm_uframes_t imx_pcm_pointer(struct snd_pcm_substream *substream)
 	return snd_dmaengine_pcm_pointer(substream);
 }
 
+static int imx_pcm_preallocate_dma_buffer(struct snd_pcm_substream *substream,
+	struct device *dev)
+{
+	size_t size = imx_pcm_hardware.buffer_bytes_max;
+	int ret;
+
+	ret = snd_pcm_lib_preallocate_pages(substream,
+				SNDRV_DMA_TYPE_DEV_IRAM,
+				dev,
+				size,
+				size);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int imx_pcm_free_dma_buffers(struct snd_pcm_substream *substream)
+{
+	return snd_pcm_lib_preallocate_free(substream);
+}
+
 static int imx_pcm_open(struct snd_pcm_substream *substream)
 {
 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
@@ -185,6 +207,10 @@ static int imx_pcm_open(struct snd_pcm_substream *substream)
 
 	snd_soc_set_runtime_hwparams(substream, &imx_pcm_hardware);
 
+	ret = imx_pcm_preallocate_dma_buffer(substream, chan->device->dev);
+	if (ret)
+		return ret;
+
 	ret = snd_pcm_hw_constraint_integer(substream->runtime,
 					    SNDRV_PCM_HW_PARAM_PERIODS);
 	if (ret < 0)
@@ -204,9 +230,20 @@ static int imx_pcm_mmap(struct snd_pcm_substream *substream,
 				     runtime->dma_bytes);
 }
 
+static int imx_pcm_close(struct snd_pcm_substream *substream)
+{
+	int ret;
+
+	ret = imx_pcm_free_dma_buffers(substream);
+	if (ret)
+		return ret;
+
+	return snd_dmaengine_pcm_close_release_chan(substream);
+}
+
 static struct snd_pcm_ops imx_pcm_ops = {
 	.open		= imx_pcm_open,
-	.close		= snd_dmaengine_pcm_close_release_chan,
+	.close		= imx_pcm_close,
 	.ioctl		= snd_pcm_lib_ioctl,
 	.hw_params	= imx_pcm_hw_params,
 	.hw_free	= imx_pcm_hw_free,
@@ -215,82 +252,21 @@ static struct snd_pcm_ops imx_pcm_ops = {
 	.mmap		= imx_pcm_mmap,
 };
 
-static int imx_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 = imx_pcm_hardware.buffer_bytes_max;
-
-	buf->dev.type = SNDRV_DMA_TYPE_DEV;
-	buf->dev.dev = pcm->card->dev;
-	buf->private_data = NULL;
-	buf->area = dma_alloc_writecombine(pcm->card->dev, size,
-					   &buf->addr, GFP_KERNEL);
-	if (!buf->area)
-		return -ENOMEM;
-
-	buf->bytes = size;
-	return 0;
-}
-
-static void imx_pcm_free_dma_buffers(struct snd_pcm *pcm)
-{
-	struct snd_pcm_substream *substream;
-	struct snd_dma_buffer *buf;
-	int stream;
-
-	for (stream = SNDRV_PCM_STREAM_PLAYBACK; stream < SNDRV_PCM_STREAM_LAST; stream++) {
-		substream = pcm->streams[stream].substream;
-		if (!substream)
-			continue;
-
-		buf = &substream->dma_buffer;
-		if (!buf->area)
-			continue;
-
-		dma_free_writecombine(pcm->card->dev, buf->bytes,
-				      buf->area, buf->addr);
-		buf->area = NULL;
-	}
-}
-
 static int imx_pcm_new(struct snd_soc_pcm_runtime *rtd)
 {
 	struct snd_card *card = rtd->card->snd_card;
-	struct snd_pcm *pcm = rtd->pcm;
-	int ret;
+	int ret = 0;
 
 	ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
 	if (ret)
 		return ret;
 
-	if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
-		ret = imx_pcm_preallocate_dma_buffer(pcm,
-			SNDRV_PCM_STREAM_PLAYBACK);
-		if (ret)
-			goto out;
-	}
-
-	if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) {
-		ret = imx_pcm_preallocate_dma_buffer(pcm,
-			SNDRV_PCM_STREAM_CAPTURE);
-		if (ret)
-			goto out;
-	}
-
-out:
-	/* free preallocated buffers in case of error */
-	if (ret)
-		imx_pcm_free_dma_buffers(pcm);
-
 	return ret;
 }
 
 static struct snd_soc_component_driver imx_soc_platform = {
 	.ops		= &imx_pcm_ops,
 	.pcm_new	= imx_pcm_new,
-	.pcm_free	= imx_pcm_free_dma_buffers,
 };
 
 int imx_pcm_platform_register(struct device *dev)