ASoC: pcm_dmaengine: Extract snd_dmaengine_pcm_refine_runtime_hwparams

When set the runtime hardware parameters, we may need to query
the capability of DMA to complete the parameters.

This patch is to Extract this operation from
dmaengine_pcm_set_runtime_hwparams function to a separate function
snd_dmaengine_pcm_refine_runtime_hwparams, that other components
which need this feature can call this function.

Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
Reviewed-by: Nicolin Chen <nicoleotsuka@gmail.com>
Link: https://lore.kernel.org/r/d728f65194e9978cbec4132b522d4fed420d704a.1569493933.git.shengjiu.wang@nxp.com
Signed-off-by: Mark Brown <broonie@kernel.org>

3 files changed, 94 insertions, 55 deletions

diff --git a/include/sound/dmaengine_pcm.h b/include/sound/dmaengine_pcm.h
index c679f6116580..b65220685920 100644
--- a/include/sound/dmaengine_pcm.h
+++ b/include/sound/dmaengine_pcm.h
@@ -83,6 +83,11 @@ void snd_dmaengine_pcm_set_config_from_dai_data(
 	const struct snd_dmaengine_dai_dma_data *dma_data,
 	struct dma_slave_config *config);
 
+int snd_dmaengine_pcm_refine_runtime_hwparams(
+	struct snd_pcm_substream *substream,
+	struct snd_dmaengine_dai_dma_data *dma_data,
+	struct snd_pcm_hardware *hw,
+	struct dma_chan *chan);
 
 /*
  * Try to request the DMA channel using compat_request_channel or
diff --git a/sound/core/pcm_dmaengine.c b/sound/core/pcm_dmaengine.c
index 89a05926ac73..5749a8a49784 100644
--- a/sound/core/pcm_dmaengine.c
+++ b/sound/core/pcm_dmaengine.c
@@ -369,4 +369,87 @@ int snd_dmaengine_pcm_close_release_chan(struct snd_pcm_substream *substream)
 }
 EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_close_release_chan);
 
+/**
+ * snd_dmaengine_pcm_refine_runtime_hwparams - Refine runtime hw params
+ * @substream: PCM substream
+ * @dma_data: DAI DMA data
+ * @hw: PCM hw params
+ * @chan: DMA channel to use for data transfers
+ *
+ * Returns 0 on success, a negative error code otherwise.
+ *
+ * This function will query DMA capability, then refine the pcm hardware
+ * parameters.
+ */
+int snd_dmaengine_pcm_refine_runtime_hwparams(
+	struct snd_pcm_substream *substream,
+	struct snd_dmaengine_dai_dma_data *dma_data,
+	struct snd_pcm_hardware *hw,
+	struct dma_chan *chan)
+{
+	struct dma_slave_caps dma_caps;
+	u32 addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
+			  BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
+			  BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
+	snd_pcm_format_t i;
+	int ret = 0;
+
+	if (!hw || !chan || !dma_data)
+		return -EINVAL;
+
+	ret = dma_get_slave_caps(chan, &dma_caps);
+	if (ret == 0) {
+		if (dma_caps.cmd_pause && dma_caps.cmd_resume)
+			hw->info |= SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME;
+		if (dma_caps.residue_granularity <= DMA_RESIDUE_GRANULARITY_SEGMENT)
+			hw->info |= SNDRV_PCM_INFO_BATCH;
+
+		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+			addr_widths = dma_caps.dst_addr_widths;
+		else
+			addr_widths = dma_caps.src_addr_widths;
+	}
+
+	/*
+	 * If SND_DMAENGINE_PCM_DAI_FLAG_PACK is set keep
+	 * hw.formats set to 0, meaning no restrictions are in place.
+	 * In this case it's the responsibility of the DAI driver to
+	 * provide the supported format information.
+	 */
+	if (!(dma_data->flags & SND_DMAENGINE_PCM_DAI_FLAG_PACK))
+		/*
+		 * Prepare formats mask for valid/allowed sample types. If the
+		 * dma does not have support for the given physical word size,
+		 * it needs to be masked out so user space can not use the
+		 * format which produces corrupted audio.
+		 * In case the dma driver does not implement the slave_caps the
+		 * default assumption is that it supports 1, 2 and 4 bytes
+		 * widths.
+		 */
+		for (i = SNDRV_PCM_FORMAT_FIRST; i <= SNDRV_PCM_FORMAT_LAST; i++) {
+			int bits = snd_pcm_format_physical_width(i);
+
+			/*
+			 * Enable only samples with DMA supported physical
+			 * widths
+			 */
+			switch (bits) {
+			case 8:
+			case 16:
+			case 24:
+			case 32:
+			case 64:
+				if (addr_widths & (1 << (bits / 8)))
+					hw->formats |= pcm_format_to_bits(i);
+				break;
+			default:
+				/* Unsupported types */
+				break;
+			}
+		}
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_refine_runtime_hwparams);
+
 MODULE_LICENSE("GPL");
diff --git a/sound/soc/soc-generic-dmaengine-pcm.c b/sound/soc/soc-generic-dmaengine-pcm.c
index 5552c66ca642..f2c98a9cbf75 100644
--- a/sound/soc/soc-generic-dmaengine-pcm.c
+++ b/sound/soc/soc-generic-dmaengine-pcm.c
@@ -118,12 +118,7 @@ static int dmaengine_pcm_set_runtime_hwparams(struct snd_pcm_substream *substrea
 	struct device *dma_dev = dmaengine_dma_dev(pcm, substream);
 	struct dma_chan *chan = pcm->chan[substream->stream];
 	struct snd_dmaengine_dai_dma_data *dma_data;
-	struct dma_slave_caps dma_caps;
 	struct snd_pcm_hardware hw;
-	u32 addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
-			  BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
-			  BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
-	snd_pcm_format_t i;
 	int ret;
 
 	if (pcm->config && pcm->config->pcm_hardware)
@@ -145,56 +140,12 @@ static int dmaengine_pcm_set_runtime_hwparams(struct snd_pcm_substream *substrea
 	if (pcm->flags & SND_DMAENGINE_PCM_FLAG_NO_RESIDUE)
 		hw.info |= SNDRV_PCM_INFO_BATCH;
 
-	ret = dma_get_slave_caps(chan, &dma_caps);
-	if (ret == 0) {
-		if (dma_caps.cmd_pause && dma_caps.cmd_resume)
-			hw.info |= SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME;
-		if (dma_caps.residue_granularity <= DMA_RESIDUE_GRANULARITY_SEGMENT)
-			hw.info |= SNDRV_PCM_INFO_BATCH;
-
-		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
-			addr_widths = dma_caps.dst_addr_widths;
-		else
-			addr_widths = dma_caps.src_addr_widths;
-	}
-
-	/*
-	 * If SND_DMAENGINE_PCM_DAI_FLAG_PACK is set keep
-	 * hw.formats set to 0, meaning no restrictions are in place.
-	 * In this case it's the responsibility of the DAI driver to
-	 * provide the supported format information.
-	 */
-	if (!(dma_data->flags & SND_DMAENGINE_PCM_DAI_FLAG_PACK))
-		/*
-		 * Prepare formats mask for valid/allowed sample types. If the
-		 * dma does not have support for the given physical word size,
-		 * it needs to be masked out so user space can not use the
-		 * format which produces corrupted audio.
-		 * In case the dma driver does not implement the slave_caps the
-		 * default assumption is that it supports 1, 2 and 4 bytes
-		 * widths.
-		 */
-		for (i = SNDRV_PCM_FORMAT_FIRST; i <= SNDRV_PCM_FORMAT_LAST; i++) {
-			int bits = snd_pcm_format_physical_width(i);
-
-			/*
-			 * Enable only samples with DMA supported physical
-			 * widths
-			 */
-			switch (bits) {
-			case 8:
-			case 16:
-			case 24:
-			case 32:
-			case 64:
-				if (addr_widths & (1 << (bits / 8)))
-					hw.formats |= pcm_format_to_bits(i);
-				break;
-			default:
-				/* Unsupported types */
-				break;
-			}
-		}
+	ret = snd_dmaengine_pcm_refine_runtime_hwparams(substream,
+							dma_data,
+							&hw,
+							chan);
+	if (ret)
+		return ret;
 
 	return snd_soc_set_runtime_hwparams(substream, &hw);
 }