2015-06-09 20:25 GMT+09:00 <gabriel@xxxxxxxxx>: > On 06/03/2015 02:05 AM, Krzysztof Kozlowski wrote: >> On 03.06.2015 04:51, gabriel@xxxxxxxxx wrote: >>> On 05/31/2015 08:47 AM, Krzysztof Kozlowski wrote: >>>> 2015-05-31 2:32 GMT+09:00 <gabriel@xxxxxxxxx>: >>>>> >>>>> Hello, >>>>> >>>>> I've been successfully using a self compiled linux kernel until version >>>>> 3.19 together with Debian Stretch. >>>>> >>>>> After upgrading the kernel to version 4.0 I see strange messages in the >>>>> logs i.e. >>>>> >>>>> May 27 22:44:01 pulseaudio[1027]: [alsa-sink-3830000.i2s-HiFi HiFi-0] >>>>> alsa-sink.c: ALSA woke us up to write new data to the device, but there >>>>> was actually nothing to write! >>>>> May 27 22:44:01 pulseaudio[1027]: [alsa-sink-3830000.i2s-HiFi HiFi-0] >>>>> alsa-sink.c: Most likely this is a bug in the ALSA driver >>>>> 'snd_soc_simple_card'. Please report this issue to the ALSA developers. >>>>> May 27 22:44:01 pulseaudio[1027]: [alsa-sink-3830000.i2s-HiFi HiFi-0] >>>>> alsa-sink.c: We were woken up with POLLOUT set -- however a subsequent >>>>> snd_pcm_avail() returned 0 or another value < min_avail. >>>>> >>>>> >>>>> I can easily play sound in perfect quality for approx the first 24h. >>>>> After that time the sound becomes distorted and is choppy/crackling. >>>>> After rebooting then the sound is optimal again. >>>>> >>>>> >>>>> I have tried to use kernel 4.0 with almost exactly the same >>>>> configuration than for 3.19 to no avail. >>>>> >>>>> Then somebody on >>>>> http://forum.odroid.com/viewtopic.php?f=82&t=13281&p=91186 gave me the >>>>> hint that the followin patch might solve the issue: >>>>> >>>>> https://github.com/prahal/linux/commit/5e60cfc9fa5101a346e29ef5f944fbbad300c72d >>>>> >>>>> >>>>> The patch did help something. I can now still play music after 2 days >>>>> but what happens is that each time I turn on music I get a choppy sound >>>>> for some time. That means the sound comes clear but every 2 seconds the >>>>> sound pauses for a fraction of a second. Which is somewhat comparable to >>>>> the issue earlier but without the heavy crackling - and that this goes >>>>> away after a couple of minutes. >>>>> >>>>> >>>>> But furthermore the sound has now simple cracklings. One in two second >>>>> approx. and they do not disappear. >>>>> >>>>> >>>>> Does anybody have an idea what could be the matter here? >>>>> >>>>> Thanks in advance. >>>> >>>> +Cc Robert, dmaengine list. >>>> >>>> Bisecting would be helpful. You could also try reverting following commits: >>>> 88987d2c75 >>>> aee4d1fac8 >>>> >>>> Other possible test case would be disabling runtime PM for pl330 DMA driver: >>>> >>>> for i in /sys/bus/amba/drivers/dma-pl330/*.[amp]dma/power ; do >>>> echo "on" > ${i}/control >>>> done >>>> >>> >>> Thanks a lot Krzysztof, >>> >>> I have reverted 88987d2c75 and aee4d1fac8 from 4.0.4 and I have still >>> audio working after 1 and 1/2 day. Unluckily the alsa error message >>> occured still once but they don't seem to be the issue here. >> >> >> +CC Marek, >> >> Robert, Marek, do you have any idea for the cause? >> > > I can now say for sure that the commits 88987d2c75 and aee4d1fac8 are > the cause for the problem. Audio was working now for 7 days. +CC Vinod Gabriel, I sent a patch which should fix the issue. Could you give it a try? Of course don't revert the other patches and don't use other workarounds. Just apply the patch on clean (vanilla would be the best) kernel. [RFT PATCH] dmaengine: Fix choppy sound because of unimplemented resume Best regards, Krzysztof -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html