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 Best regards, Krzysztof -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html