Re: exynos4412: Audio dies after one day on kernel 4.0

[Krzysztof Kozlowski <k.kozlowski@samsung.com>]

On 03.06.2015 04:51, gabriel@unseen.is wrote:
> On 05/31/2015 08:47 AM, Krzysztof Kozlowski wrote:
>> 2015-05-31 2:32 GMT+09:00  <gabriel@unseen.is>:
>>>
>>> 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?

Best regards,
Krzysztof