Need to revisit, and do in a different way.
https://github.com/respeaker/seeed-voicecard/issues/290
6mics / linear 4 mics: fails to record against v5.10 kernel
https://github.com/raspberrypi/linux/issues/4279
[regression] alsa system call blocks on record between 5.4.83 and 5.5.19
In v5.5,
commit 4378f1fbe924054a09ff0d4e39e1a581b9245252
Author: Peter Ujfalusi <peter.ujfalusi@ti.com>
Date: Fri Sep 27 10:16:46 2019 +0300
ASoC: soc-pcm: Use different sequence for start/stop trigger
On stream stop currently we stop the DMA first followed by the CPU DAI.
This can cause underflow (playback) or overflow (capture) on the DAI side
as the DMA is no longer feeding data while the DAI is still active.
It can be observed easily if the DAI side does not have FIFO (or it is
disabled) to survive the time while the DMA is stopped, but still can
happen on relatively slow CPUs when relatively high sampling rate is used:
the FIFO is drained between the time the DMA is stopped and the DAI is
stopped.
It can only fixed by using different sequence within trigger for 'stop' and
'start':
case SNDRV_PCM_TRIGGER_START:
case SNDRV_PCM_TRIGGER_RESUME:
case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
Trigger order: dai_link, DMA, CPU DAI then the codec
case SNDRV_PCM_TRIGGER_STOP:
case SNDRV_PCM_TRIGGER_SUSPEND:
case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
Trigger order: codec, CPU DAI, DMA then dai_link
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20190927071646.22319-1-peter.ujfalusi@ti.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Reference:
commit e2978c45e5ed3bab7f69477b882ef588185b30cc
Author: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Date: Fri Jul 17 09:21:54 2020 +0900
ASoC: soc-dai: remove .digital_mute
All drivers are now using .mute_stream.
Let's remove .digital_mute.
commit 22e9b54307987787efa0ee534aa9e31982ec1161
Merge: dc9584c5a3b8 a0234d0e6014
Author: Mark Brown <broonie@kernel.org>
Date: Fri Jul 17 14:47:04 2020 +0100
Merge series "ASoC: merge .digital_mute() into .mute_stream()" from Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>:
These are v4 digital_mute() patch which adjusts
to atmel which had conflict on v3.
v3 -> v4
- tidyup for atmel which had conflict
$ git diff dc9584c5a3b8...a0234d0e6014
commit bdd0c277d9846977ec3f175341d4e7475ed26ef7
Merge: d235b2823698 50891431aaad
Author: Mark Brown <broonie@kernel.org>
Date: Thu Jul 16 23:51:51 2020 +0100
Merge series "ASoC: merge .digital_mute() into .mute_stream()" from Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>:
These are v3 patch-set.
ALSA SoC has 2 mute callbacks (= .digital_mute(), .mute_stream()).
But the difference between these 2 are very small.
.digital_mute() is for Playback
.mute_stream() is for Playback/Capture
This patch-set adds new .no_capture_mute flag and emulate
.digital_mute() by .mute_stream().
v2 -> v3
- uses "xxx_mute_stream" for .mute_stream naming
if it was better
- removed verbose Cc email address
$ git diff d235b2823698...50891431aaad
commit 350d993510115e3d9e78f1b3359bff7b68e88418
Author: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Date: Thu Jul 9 10:55:41 2020 +0900
ASoC: soc-dai.c: add .no_capture_mute support
perl -pi -e 's(->capture_active)(->stream_active\[SNDRV_PCM_STREAM_CAPTURE\])g' *.c
perl -pi -e 's(->playback_active)(->stream_active\[SNDRV_PCM_STREAM_PLAYBACK\])g' *.c
commit 0f6011fd79a2fb92cb80177fd6bdc8aac3a3cd93
Author: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Date: Mon Feb 17 17:28:15 2020 +0900
ASoC: soc-pcm: merge playback/cature_active into stream_active
DAI has playback_active and capture_active to care usage count.
OTOH, we have SNDRV_PCM_STREAM_PLAYBACK/CAPTURE.
But because of this kind of implementation mismatch,
ALSA SoC has many verbose code.
To solve this issue, this patch merge playback_active/capture_active
into stream_active[2];
See include/linux/compiler_attributes.h:
/*
* Add the pseudo keyword 'fallthrough' so case statement blocks
* must end with any of these keywords:
* break;
* fallthrough;
* goto <label>;
* return [expression];
*
* gcc: https://gcc.gnu.org/onlinedocs/gcc/Statement-Attributes.html#Statement-Attributes
*/
-if __has_attribute(__fallthrough__)
- define fallthrough __attribute__((__fallthrough__))
-else
- define fallthrough do {} while (0) /* fallthrough */
-endif
The whole warning is quite long but looks like this:
CC [M] seeed-voicecard/ac108.o
In file included from ./include/linux/printk.h:331,
from ./include/linux/kernel.h:15,
from ./include/linux/list.h:9,
from ./include/linux/module.h:12,
from seeed-voicecard/ac108.c:15:
seeed-voicecard/ac108.c: In function ‘ac108_set_fmt’:
./include/linux/dynamic_debug.h:122:52: warning: this statement may fall through [-Wimplicit-fallthrough=]
122 | #define __dynamic_func_call(id, fmt, func, ...) do { \
| ^
./include/linux/dynamic_debug.h:143:2: note: in expansion of macro ‘__dynamic_func_call’
143 | __dynamic_func_call(__UNIQUE_ID(ddebug), fmt, func, ##__VA_ARGS__)
| ^~~~~~~~~~~~~~~~~~~
./include/linux/dynamic_debug.h:157:2: note: in expansion of macro ‘_dynamic_func_call’
157 | _dynamic_func_call(fmt,__dynamic_dev_dbg, \
| ^~~~~~~~~~~~~~~~~~
./include/linux/device.h:1795:2: note: in expansion of macro ‘dynamic_dev_dbg’
1795 | dynamic_dev_dbg(dev, dev_fmt(fmt), ##__VA_ARGS__)
| ^~~~~~~~~~~~~~~
seeed-voicecard/ac108.c:866:4: note: in expansion of macro ‘dev_dbg’
866 | dev_dbg(dai->dev, "used as slave when AC101 is master\n");
| ^~~~~~~
seeed-voicecard/ac108.c:868:2: note: here
868 | case SND_SOC_DAIFMT_CBS_CFS: /*AC108 Slave*/
| ^~~~
