linux-stable/sound/soc/qcom
Stephan Gerhold 7f2430cda8
ASoC: qcom: q6asm-dai: Add SNDRV_PCM_INFO_BATCH flag
At the moment, playing audio with PulseAudio with the qdsp6 driver
results in distorted sound. It seems like its timer-based scheduling
does not work properly with qdsp6 since setting tsched=0 in
the PulseAudio configuration avoids the issue.

Apparently this happens when the pointer() callback is not accurate
enough. There is a SNDRV_PCM_INFO_BATCH flag that can be used to stop
PulseAudio from using timer-based scheduling by default.

According to https://www.alsa-project.org/pipermail/alsa-devel/2014-March/073816.html:

    The flag is being used in the sense explained in the previous audio
    meeting -- the data transfer granularity isn't fine enough but aligned
    to the period size (or less).

q6asm-dai reports the position as multiple of

    prtd->pcm_count = snd_pcm_lib_period_bytes(substream)

so it indeed just a multiple of the period size.

Therefore adding the flag here seems appropriate and makes audio
work out of the box.

Fixes: 2a9e92d371 ("ASoC: qdsp6: q6asm: Add q6asm dai driver")
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
Reviewed-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20200330175210.47518-1-stephan@gerhold.net
Signed-off-by: Mark Brown <broonie@kernel.org>
2020-03-31 19:23:54 +01:00
..
qdsp6 ASoC: qcom: q6asm-dai: Add SNDRV_PCM_INFO_BATCH flag 2020-03-31 19:23:54 +01:00
apq8016_sbc.c ASoC: qcom: use asoc_rtd_to_cpu() / asoc_rtd_to_codec() macro for DAI pointer 2020-03-27 14:44:44 +00:00
apq8096.c ASoC: qcom: use asoc_rtd_to_cpu() / asoc_rtd_to_codec() macro for DAI pointer 2020-03-27 14:44:44 +00:00
common.c ASoC: qcom: common: Include link-name in error messages 2019-09-05 18:15:39 +01:00
common.h ASoC: qcom: remove unused header files from common.h 2018-08-06 12:50:07 +01:00
Kconfig ASoC: qcom: sdm845: handle soundwire stream 2020-03-18 21:25:53 +00:00
lpass-apq8016.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 284 2019-06-05 17:36:37 +02:00
lpass-cpu.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 284 2019-06-05 17:36:37 +02:00
lpass-ipq806x.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 284 2019-06-05 17:36:37 +02:00
lpass-lpaif-reg.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 284 2019-06-05 17:36:37 +02:00
lpass-platform.c ASoC: qcom: use asoc_rtd_to_cpu() / asoc_rtd_to_codec() macro for DAI pointer 2020-03-27 14:44:44 +00:00
lpass.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 284 2019-06-05 17:36:37 +02:00
Makefile ASoC: qcom: make common.c as proper module 2018-08-06 12:50:04 +01:00
sdm845.c ASoC: qcom: use asoc_rtd_to_cpu() / asoc_rtd_to_codec() macro for DAI pointer 2020-03-27 14:44:44 +00:00
storm.c ASoC: qcom: use asoc_rtd_to_cpu() / asoc_rtd_to_codec() macro for DAI pointer 2020-03-27 14:44:44 +00:00