2015-12-11 03:36:43

by Koro Chen

Subject: [RFC PATCH] ASoC: dpcm: Apply symmetry for DPCM

From: PC Liao <[email protected]>

DPCM does not fully support symmetry attributes. soc_pcm_apply_symmetry()
is skipped in soc_pcm_open() for DPCM, without being applied elsewhere.
So HW parameters cannot be correctly limited, and user space can do
playback/capture at different rates while HW actually does not support it.
soc_pcm_params_symmetry() will return error and the second stream stops.

This patch adds soc_pcm_apply_symmetry() for FE, BE, and codec DAIs
in DPCM path that was skipped in soc_pcm_open().

Signed-off-by: PC Liao <[email protected]>
Signed-off-by: Koro Chen <[email protected]>
---
sound/soc/soc-pcm.c | 57 +++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 57 insertions(+)

diff --git a/sound/soc/soc-pcm.c b/sound/soc/soc-pcm.c
index 67ef1a0..2a2ca22 100644
--- a/sound/soc/soc-pcm.c
+++ b/sound/soc/soc-pcm.c
@@ -1614,6 +1614,56 @@ static void dpcm_set_fe_update_state(struct snd_soc_pcm_runtime *fe,
snd_pcm_stream_unlock_irq(substream);
}

+static int dpcm_apply_symmetry(struct snd_pcm_substream *fe_substream,
+ int stream)
+{
+ struct snd_soc_dpcm *dpcm;
+ struct snd_soc_pcm_runtime *fe = fe_substream->private_data;
+ struct snd_soc_dai *fe_cpu_dai = fe->cpu_dai;
+ int err;
+
+ /* apply symmetry for FE */
+ if (soc_pcm_has_symmetry(fe_substream))
+ fe_substream->runtime->hw.info |= SNDRV_PCM_INFO_JOINT_DUPLEX;
+
+ /* Symmetry only applies if we've got an active stream. */
+ if (fe_cpu_dai->active) {
+ err = soc_pcm_apply_symmetry(fe_substream, fe_cpu_dai);
+ if (err < 0)
+ return err;
+ }
+
+ /* apply symmetry for BE */
+ list_for_each_entry(dpcm, &fe->dpcm[stream].be_clients, list_be) {
+ struct snd_soc_pcm_runtime *be = dpcm->be;
+ struct snd_pcm_substream *be_substream =
+ snd_soc_dpcm_get_substream(be, stream);
+ struct snd_soc_pcm_runtime *rtd = be_substream->private_data;
+ int i;
+
+ if (soc_pcm_has_symmetry(be_substream))
+ be_substream->runtime->hw.info |= SNDRV_PCM_INFO_JOINT_DUPLEX;
+
+ /* Symmetry only applies if we've got an active stream. */
+ if (rtd->cpu_dai->active) {
+ err = soc_pcm_apply_symmetry(be_substream, rtd->cpu_dai);
+ if (err < 0)
+ return err;
+ }
+
+ for (i = 0; i < rtd->num_codecs; i++) {
+ if (rtd->codec_dais[i]->active) {
+ err = soc_pcm_apply_symmetry(be_substream,
+ rtd->codec_dais[i]);
+ if (err < 0)
+ return err;
+ }
+ }
+ }
+
+ return 0;
+}
+
static int dpcm_fe_dai_startup(struct snd_pcm_substream *fe_substream)
{
struct snd_soc_pcm_runtime *fe = fe_substream->private_data;
@@ -1642,6 +1692,13 @@ static int dpcm_fe_dai_startup(struct snd_pcm_substream *fe_substream)
dpcm_set_fe_runtime(fe_substream);
snd_pcm_limit_hw_rates(runtime);

+ ret = dpcm_apply_symmetry(fe_substream, stream);
+ if (ret < 0) {
+ dev_err(fe->dev, "ASoC: failed to apply dpcm symmetry %d\n",
+ ret);
+ goto unwind;
+ }
+
dpcm_set_fe_update_state(fe, stream, SND_SOC_DPCM_UPDATE_NO);
return 0;

--
1.7.9.5

2015-12-11 19:09:33

by Liam Girdwood

Subject: Re: [RFC PATCH] ASoC: dpcm: Apply symmetry for DPCM

On Fri, 2015-12-11 at 11:33 +0800, Koro Chen wrote:
> From: PC Liao <[email protected]>
>
> DPCM does not fully support symmetry attributes. soc_pcm_apply_symmetry()
> is skipped in soc_pcm_open() for DPCM, without being applied elsewhere.
> So HW parameters cannot be correctly limited, and user space can do
> playback/capture at different rates while HW actually does not support it.
> soc_pcm_params_symmetry() will return error and the second stream stops.
>
> This patch adds soc_pcm_apply_symmetry() for FE, BE, and codec DAIs
> in DPCM path that was skipped in soc_pcm_open().
>
> Signed-off-by: PC Liao <[email protected]>
> Signed-off-by: Koro Chen <[email protected]>

Acked-by: Liam Girdwood <[email protected]>