[alsa-devel] [PATCH 04/17] ASoC: dmaengine_pcm: Add support for compat platforms
Lars-Peter Clausen
lars at metafoo.de
Mon Apr 15 19:19:51 CEST 2013
Add support for platforms which don't use devicetree yet or have to optionally
support a non-devicetree way to request the DMA channel. The patch adds the
compat_request_channel and compat_filter_fn callbacks to the
snd_dmaengine_pcm_config struct. If the compat_request_channel is implemented it
will be used to request the DMA channel. If not dma_request_channel with
compat_filter_fn as the filter function will be used to request the channel.
The patch also exports the snd_dmaengine_pcm_request_chan() function, since
compat platforms will want to use it to request their DMA channel.
Signed-off-by: Lars-Peter Clausen <lars at metafoo.de>
---
include/sound/dmaengine_pcm.h | 29 +++++++++++++++++++++++++++++
sound/soc/soc-dmaengine-pcm.c | 14 ++++++++++++--
sound/soc/soc-generic-dmaengine-pcm.c | 32 +++++++++++++++++++++++++++-----
3 files changed, 68 insertions(+), 7 deletions(-)
diff --git a/include/sound/dmaengine_pcm.h b/include/sound/dmaengine_pcm.h
index e0bf24e..1a7897a 100644
--- a/include/sound/dmaengine_pcm.h
+++ b/include/sound/dmaengine_pcm.h
@@ -16,6 +16,7 @@
#define __SOUND_DMAENGINE_PCM_H__
#include <sound/pcm.h>
+#include <sound/soc.h>
#include <linux/dmaengine.h>
/**
@@ -46,6 +47,8 @@ int snd_dmaengine_pcm_open_request_chan(struct snd_pcm_substream *substream,
dma_filter_fn filter_fn, void *filter_data);
int snd_dmaengine_pcm_close_release_chan(struct snd_pcm_substream *substream);
+struct dma_chan *snd_dmaengine_pcm_request_channel(dma_filter_fn filter_fn,
+ void *filter_data);
struct dma_chan *snd_dmaengine_pcm_get_chan(struct snd_pcm_substream *substream);
/**
@@ -72,17 +75,43 @@ void snd_dmaengine_pcm_set_config_from_dai_data(
const struct snd_dmaengine_dai_dma_data *dma_data,
struct dma_slave_config *config);
+
+/*
+ * Try to request the DMA channel using compat_request_channel or
+ * compat_filter_fn if it couldn't be requested through devicetree.
+ */
+#define SND_DMAENGINE_PCM_FLAG_COMPAT BIT(0)
+/*
+ * Don't try to request the DMA channels through devicetree. This flag only
+ * makes sense if SND_DMAENGINE_PCM_FLAG_COMPAT is set as well.
+ */
+#define SND_DMAENGINE_PCM_FLAG_NO_DT BIT(1)
+
/**
* struct snd_dmaengine_pcm_config - Configuration data for dmaengine based PCM
* @prepare_slave_config: Callback used to fill in the DMA slave_config for a
* PCM substream. Will be called from the PCM drivers hwparams callback.
+ * @compat_request_channel: Callback to request a DMA channel for platforms
+ * which do not use devicetree.
+ * @compat_filter_fn: Will be used as the filter function when requesting a
+ * channel for platforms which do not use devicetree. The filter parameter
+ * will be the DAI's DMA data.
* @pcm_hardware: snd_pcm_hardware struct to be used for the PCM.
* @prealloc_buffer_size: Size of the preallocated audio buffer.
+ *
+ * Note: If both compat_request_channel and compat_filter_fn are set
+ * compat_request_channel will be used to request the channel and
+ * compat_filter_fn will be ignored. Otherwise the channel will be requested
+ * using dma_request_channel with compat_filter_fn as the filter function.
*/
struct snd_dmaengine_pcm_config {
int (*prepare_slave_config)(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *params,
struct dma_slave_config *slave_config);
+ struct dma_chan *(*compat_request_channel)(
+ struct snd_soc_pcm_runtime *rtd,
+ struct snd_pcm_substream *substream);
+ dma_filter_fn compat_filter_fn;
const struct snd_pcm_hardware *pcm_hardware;
unsigned int prealloc_buffer_size;
diff --git a/sound/soc/soc-dmaengine-pcm.c b/sound/soc/soc-dmaengine-pcm.c
index b0420a7..aa924d9 100644
--- a/sound/soc/soc-dmaengine-pcm.c
+++ b/sound/soc/soc-dmaengine-pcm.c
@@ -254,7 +254,16 @@ snd_pcm_uframes_t snd_dmaengine_pcm_pointer(struct snd_pcm_substream *substream)
}
EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_pointer);
-static struct dma_chan *dmaengine_pcm_request_channel(dma_filter_fn filter_fn,
+/**
+ * snd_dmaengine_pcm_request_channel - Request channel for the dmaengine PCM
+ * @filter_fn: Filter function used to request the DMA channel
+ * @filter_data: Data passed to the DMA filter function
+ *
+ * Returns NULL or the requested DMA channel.
+ *
+ * This function request a DMA channel for usage with dmaengine PCM.
+ */
+struct dma_chan *snd_dmaengine_pcm_request_channel(dma_filter_fn filter_fn,
void *filter_data)
{
dma_cap_mask_t mask;
@@ -265,6 +274,7 @@ static struct dma_chan *dmaengine_pcm_request_channel(dma_filter_fn filter_fn,
return dma_request_channel(mask, filter_fn, filter_data);
}
+EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_request_channel);
/**
* snd_dmaengine_pcm_open - Open a dmaengine based PCM substream
@@ -320,7 +330,7 @@ int snd_dmaengine_pcm_open_request_chan(struct snd_pcm_substream *substream,
dma_filter_fn filter_fn, void *filter_data)
{
return snd_dmaengine_pcm_open(substream,
- dmaengine_pcm_request_channel(filter_fn, filter_data));
+ snd_dmaengine_pcm_request_channel(filter_fn, filter_data));
}
EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_open_request_chan);
diff --git a/sound/soc/soc-generic-dmaengine-pcm.c b/sound/soc/soc-generic-dmaengine-pcm.c
index acfc926..d6e6380 100644
--- a/sound/soc/soc-generic-dmaengine-pcm.c
+++ b/sound/soc/soc-generic-dmaengine-pcm.c
@@ -29,6 +29,7 @@ struct dmaengine_pcm {
struct dma_chan *chan[SNDRV_PCM_STREAM_CAPTURE + 1];
const struct snd_dmaengine_pcm_config *config;
struct snd_soc_platform platform;
+ bool compat;
};
static struct dmaengine_pcm *soc_platform_to_pcm(struct snd_soc_platform *p)
@@ -121,6 +122,19 @@ static void dmaengine_pcm_free(struct snd_pcm *pcm)
snd_pcm_lib_preallocate_free_for_all(pcm);
}
+static struct dma_chan *dmaengine_pcm_compat_request_channel(
+ struct snd_soc_pcm_runtime *rtd,
+ struct snd_pcm_substream *substream)
+{
+ struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform);
+
+ if (pcm->config->compat_request_channel)
+ return pcm->config->compat_request_channel(rtd, substream);
+
+ return snd_dmaengine_pcm_request_channel(pcm->config->compat_filter_fn,
+ snd_soc_dai_get_dma_data(rtd->cpu_dai, substream));
+}
+
static int dmaengine_pcm_new(struct snd_soc_pcm_runtime *rtd)
{
struct dmaengine_pcm *pcm = soc_platform_to_pcm(rtd->platform);
@@ -134,6 +148,11 @@ static int dmaengine_pcm_new(struct snd_soc_pcm_runtime *rtd)
if (!substream)
continue;
+ if (!pcm->chan[i] && pcm->compat) {
+ pcm->chan[i] = dmaengine_pcm_compat_request_channel(rtd,
+ substream);
+ }
+
if (!pcm->chan[i]) {
dev_err(rtd->platform->dev,
"Missing dma channel for stream: %d\n", i);
@@ -171,6 +190,7 @@ static const struct snd_soc_platform_driver dmaengine_pcm_platform = {
.ops = &dmaengine_pcm_ops,
.pcm_new = dmaengine_pcm_new,
.pcm_free = dmaengine_pcm_free,
+ .probe_order = SND_SOC_COMP_ORDER_LATE,
};
static const char * const dmaengine_pcm_dma_channel_names[] = {
@@ -190,18 +210,20 @@ int snd_dmaengine_pcm_register(struct device *dev,
struct dmaengine_pcm *pcm;
unsigned int i;
- if (!dev->of_node)
- return -EINVAL;
-
pcm = kzalloc(sizeof(*pcm), GFP_KERNEL);
if (!pcm)
return -ENOMEM;
pcm->config = config;
- for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE; i++) {
- pcm->chan[i] = of_dma_request_slave_channel(dev->of_node,
+ if (flags & SND_DMAENGINE_PCM_FLAG_COMPAT)
+ pcm->compat = true;
+
+ if (!(flags & SND_DMAENGINE_PCM_FLAG_NO_DT) && dev->of_node) {
+ for (i = SNDRV_PCM_STREAM_PLAYBACK; i <= SNDRV_PCM_STREAM_CAPTURE; i++) {
+ pcm->chan[i] = of_dma_request_slave_channel(dev->of_node,
dmaengine_pcm_dma_channel_names[i]);
+ }
}
return snd_soc_add_platform(dev, &pcm->platform,
--
1.8.0
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