[PATCH 3/3] ASoC: fsl_asrc_dma: allocate memory from dma device

Shengjiu Wang shengjiu.wang at nxp.com
Wed Jan 28 18:18:53 AEDT 2026


As the dma device may support dma-coherent property on the i.MX952,
allocate memory from dma device to make asrc driver to be compatible with
such a case.

Signed-off-by: Shengjiu Wang <shengjiu.wang at nxp.com>
---
 sound/soc/fsl/fsl_asrc_dma.c | 48 ++++++++++++++++++++++++++++++------
 1 file changed, 41 insertions(+), 7 deletions(-)

diff --git a/sound/soc/fsl/fsl_asrc_dma.c b/sound/soc/fsl/fsl_asrc_dma.c
index 7dacc06b2f02..b8fe242d53db 100644
--- a/sound/soc/fsl/fsl_asrc_dma.c
+++ b/sound/soc/fsl/fsl_asrc_dma.c
@@ -449,18 +449,52 @@ fsl_asrc_dma_pcm_pointer(struct snd_soc_component *component,
 static int fsl_asrc_dma_pcm_new(struct snd_soc_component *component,
 				struct snd_soc_pcm_runtime *rtd)
 {
-	struct snd_card *card = rtd->card->snd_card;
+	struct device *dev = component->dev;
+	struct fsl_asrc *asrc = dev_get_drvdata(dev);
+	struct fsl_asrc_pair *pair;
 	struct snd_pcm *pcm = rtd->pcm;
+	struct dma_chan *chan;
 	int ret;
 
-	ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
-	if (ret) {
-		dev_err(card->dev, "failed to set DMA mask\n");
-		return ret;
+	pair = kzalloc(sizeof(*pair) + asrc->pair_priv_size, GFP_KERNEL);
+	if (!pair)
+		return -ENOMEM;
+
+	pair->asrc = asrc;
+	pair->private = (void *)pair + sizeof(struct fsl_asrc_pair);
+
+	/* Request a dummy pair, which will be released later.
+	 * Request pair function needs channel num as input, for this
+	 * dummy pair, we just request "1" channel temporarily.
+	 */
+	ret = asrc->request_pair(1, pair);
+	if (ret < 0) {
+		dev_err(dev, "failed to request asrc pair\n");
+		goto req_pair_err;
 	}
 
-	return snd_pcm_set_fixed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV,
-					    card->dev, FSL_ASRC_DMABUF_SIZE);
+	/* Request a dummy dma channel, which will be released later. */
+	chan = asrc->get_dma_channel(pair, IN);
+	if (!chan) {
+		dev_err(dev, "failed to get dma channel\n");
+		ret = -EINVAL;
+		goto dma_chan_err;
+	}
+
+	ret = snd_pcm_set_fixed_buffer_all(pcm,
+					   SNDRV_DMA_TYPE_DEV,
+					   chan->device->dev,
+					   FSL_ASRC_DMABUF_SIZE);
+
+	dma_release_channel(chan);
+
+dma_chan_err:
+	asrc->release_pair(pair);
+
+req_pair_err:
+	kfree(pair);
+
+	return ret;
 }
 
 struct snd_soc_component_driver fsl_asrc_component = {
-- 
2.34.1



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