[ Upstream commit 2f9426905a ]
The rpmsg pcm device is a device which should support
double buffering.
Found this issue with pipewire. When there is no
SNDRV_PCM_INFO_BATCH flag in driver, the pipewire will
set headroom to be zero, and because rpmsg pcm device
don't support residue report, when the latency setting
is small, the "delay" always larger than "target" in
alsa-pcm.c, that reading next period data is not
scheduled on time.
With SNDRV_PCM_INFO_BATCH flag in driver, the pipewire
will select a smaller period size for device, then
the task of reading next period data will be scheduled
on time.
Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
Link: https://lore.kernel.org/r/1694414287-13291-1-git-send-email-shengjiu.wang@nxp.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
As the standard buffer allocation helper supports WC pages now, we can
convert imx-pcm-rpmsg driver to use that. This allows us to remove
lots of superfluous code.
Cc: Nicolin Chen <nicoleotsuka@gmail.com>
Cc: Xiubo Li <Xiubo.Lee@gmail.com>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: Shengjiu Wang <shengjiu.wang@gmail.com>
Acked-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20210802072815.13551-9-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
The format in rpmsg is defained as unsigned char, there is warning
when convert snd_pcm_format_t to it.
sound/soc/fsl/imx-pcm-rpmsg.c:164:43: sparse: warning: incorrect type in assignment (different base types)
sound/soc/fsl/imx-pcm-rpmsg.c:164:43: sparse: expected unsigned char format
sound/soc/fsl/imx-pcm-rpmsg.c:164:43: sparse: got restricted snd_pcm_format_t [usertype]
sound/soc/fsl/imx-pcm-rpmsg.c:167:43: sparse: warning: incorrect type in assignment (different base types)
sound/soc/fsl/imx-pcm-rpmsg.c:167:43: sparse: expected unsigned char format
sound/soc/fsl/imx-pcm-rpmsg.c:167:43: sparse: got restricted snd_pcm_format_t [usertype]
Refine the unused RPMSG_DSD_U16_LE and RPMSG_DSD_U32_LE for these
case to fix this sparse warning.
Fixes: 3c00eceb2a ("ASoC: imx-pcm-rpmsg: Add platform driver for audio base on rpmsg")
Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
Link: https://lore.kernel.org/r/1620268240-1005-1-git-send-email-shengjiu.wang@nxp.com
Signed-off-by: Mark Brown <broonie@kernel.org>
cppcheck warning:
assigned a value that is never used. [unreadVariable]
int written_num = 0;
^
sound/soc/fsl/imx-pcm-rpmsg.c:547:18: style: Variable 'written_num' is
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20210426214701.235106-5-pierre-louis.bossart@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Platform driver based on rpmsg is the interface for sending and
receiving rpmsg to and from M core. It will tell the Cortex-M core
sound format/rate/channel, where is the data buffer, where is
the period size, when to start, when to stop and when suspend
or resume happen, each this behavior there is defined rpmsg
command.
Especially we designed the low power audio case, that is to
allocate a large buffer and fill the data, then Cortex-A core can go
to sleep mode, Cortex-M core continue to play the sound, when the
buffer is consumed, Cortex-M core will trigger the Cortex-A core to
wake up.
Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
Link: https://lore.kernel.org/r/1615516725-4975-6-git-send-email-shengjiu.wang@nxp.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Shengjiu Wang
Takashi Iwai
Mark Brown
Pierre-Louis Bossart