ASoC: dmaengine-pcm: Add support for querying DMA capabilities
Currently each platform making use the the generic dmaengine PCM driver still
needs to provide a custom snd_pcm_hardware struct which specifies the
capabilities of the DMA controller, e.g. the maximum period size that can be
supported. This patch adds code which uses the newly introduced
dma_get_slave_caps() API to query this information from the dmaengine driver.
The new code path will only be taken if the 'pcm_hardware' field of the
snd_dmaengine_pcm_config struct is NULL.
The patch also introduces a new 'fifo_size' field to the
snd_dmaengine_dai_dma_data struct which is used to initialize the
snd_pcm_hardware 'fifo_size' field and needs to be set by the DAI driver.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@linaro.org>
diff --git a/sound/soc/soc-generic-dmaengine-pcm.c b/sound/soc/soc-generic-dmaengine-pcm.c
index e29ec3c..c39e19e 100644
--- a/sound/soc/soc-generic-dmaengine-pcm.c
+++ b/sound/soc/soc-generic-dmaengine-pcm.c
@@ -36,6 +36,15 @@
return container_of(p, struct dmaengine_pcm, platform);
}
+static struct device *dmaengine_dma_dev(struct dmaengine_pcm *pcm,
+ struct snd_pcm_substream *substream)
+{
+ if (!pcm->chan[substream->stream])
+ return NULL;
+
+ return pcm->chan[substream->stream]->device->dev;
+}
+
/**
* snd_dmaengine_pcm_prepare_slave_config() - Generic prepare_slave_config callback
* @substream: PCM substream
@@ -92,6 +101,42 @@
return snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(params));
}
+static int dmaengine_pcm_set_runtime_hwparams(struct snd_pcm_substream *substream)
+{
+ struct snd_soc_pcm_runtime *rtd = substream->private_data;
+ struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform);
+ 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;
+ int ret;
+
+ if (pcm->config->pcm_hardware)
+ return snd_soc_set_runtime_hwparams(substream,
+ pcm->config->pcm_hardware);
+
+ dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
+
+ memset(&hw, 0, sizeof(hw));
+ hw.info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
+ SNDRV_PCM_INFO_INTERLEAVED;
+ hw.periods_min = 2;
+ hw.periods_max = UINT_MAX;
+ hw.period_bytes_min = 256;
+ hw.period_bytes_max = dma_get_max_seg_size(dma_dev);
+ hw.buffer_bytes_max = SIZE_MAX;
+ hw.fifo_size = dma_data->fifo_size;
+
+ ret = dma_get_slave_caps(chan, &dma_caps);
+ if (ret == 0) {
+ if (dma_caps.cmd_pause)
+ hw.info |= SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME;
+ }
+
+ return snd_soc_set_runtime_hwparams(substream, &hw);
+}
+
static int dmaengine_pcm_open(struct snd_pcm_substream *substream)
{
struct snd_soc_pcm_runtime *rtd = substream->private_data;
@@ -99,23 +144,13 @@
struct dma_chan *chan = pcm->chan[substream->stream];
int ret;
- ret = snd_soc_set_runtime_hwparams(substream,
- pcm->config->pcm_hardware);
+ ret = dmaengine_pcm_set_runtime_hwparams(substream);
if (ret)
return ret;
return snd_dmaengine_pcm_open(substream, chan);
}
-static struct device *dmaengine_dma_dev(struct dmaengine_pcm *pcm,
- struct snd_pcm_substream *substream)
-{
- if (!pcm->chan[substream->stream])
- return NULL;
-
- return pcm->chan[substream->stream]->device->dev;
-}
-
static void dmaengine_pcm_free(struct snd_pcm *pcm)
{
snd_pcm_lib_preallocate_free_for_all(pcm);
