[Letux-kernel] [PATCH 0/8] Get sound playback working on the Pandora again

Stefan Leichter sle85276 at gmx.de
Fri Jan 7 21:17:50 CET 2022

Hi Grond,

On 07.01.22 18:28, Grond wrote:
> Hey Stephan.
> I'm pretty sure I know what's causing at least one of the problems.
> On Fri, Jan 07, 2022 at 05:50:34PM +0100, Stefan Leichter wrote:
>> Hello Grond,
>> a late happy new year and thank you for your work.
>> On 31.12.21 01:41, Grond wrote:
>>> Note that these changes only fix playback. Recording sound does not
>>> currently work for as yet unknown reasons. However, given the (mind
>>> boggling) number of ALSA kcontrols exposed by the TWL4030's sound
>>> capture codec, it is likely that there is just a switch that is turned
>>> off somewhere.
>> Today I tried on my 1GHz pandora the new kernel from hns (5.16.0-rc8-letux+) with includes you patches. Did you notice in /var/log/syslog or dmesg output the line:
>> [   17.557952] omap3pandora-sound omap3pandora-sound: Failed to register sound card: -517
> -517 is -EPROBE_DEFER. As Nicolaus pointed out, it just means that the
> first attempt to probe the driver failed because one of the components
> it depends on wasn't probed yet. However, this should not be considered
> a good reason to use dev_err (since it's expected behaviour). Perhaps I
> should modify the patch series?
>> This can be the reason for the not working audio input. If you change in soc-core.c line 858 from dev_dbg to dev_err you will see the problem in dmesg:
>> [   17.246490] omap3pandora-sound omap3pandora-sound: ASoC: codec component pcm1773-codec not found for link PCM1773
>> One thing was driving me mad. When I login only via ssh aplay -l doesn't show any audio devices. After login on the pandora keyboard the playback device (pcm1773-hifi-0) appears and is usable.
> I have no good explanation for this. Generally speaking, what is the
> timing for you logging in via SSH versus the keyboard? If SSH is always
> earlier, it may simply be the driver taking a while to load (but I
> cannot imagine why that would be).

Not exactly sure what you mean with timing, but let me try to explain what I did now:

The pandora was started at 20:50. Booting to the console prompt takes about 35 seconds. At 20:55 login via ssh, check for the loaded modules, run aplay, login on the console, second aplay:

letux at letux:~$ lsmod | grep -e pandora -e pcm ; aplay -l ; date
snd_soc_pcm1773        16384  1
pandora_bl             16384  0
snd_soc_omap3pandora    16384  0
pandora_nub            20480  0
aplay: device_list:270: no soundcards found...
Fri Jan  7 20:55:32 UTC 2022
letux at letux:~$ aplay -l ; date
**** List of PLAYBACK Hardware Devices ****
card 0: omap3pandora [omap3pandora], device 0: HiFi Out pcm1773-hifi-0 [HiFi Out pcm1773-hifi-0]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
Fri Jan  7 20:55:50 UTC 2022
letux at letux:~$

I can wait longer between the startup an the ssh login, just suggest a duration.

If I first login at the console the playback device will appear directly at the first aplay call after the login, even if I did not wait for five minutes after starting the pandora.


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