i.mx6Q audio codec wm8962 sometimes failed to play

[wallyyeh]

Hi, our product is using base on SDK_3.0.35-4.1.0_GA, audio codec is the same as i.mx6Q SabrdSD board(wm8962 but without PMIC)

    Recently, our customer complain about our i.mx6Q product sometimes can't play or record sound.

and I only got one line error message: "wm8962 0-001a: DC servo timed out"

    When this issue happen, aplay or arecord will just stuck, 'till press ctrl+c to interrupt the paly/record process.

and after the interruption done, aplay/arecord once again working fine.

    I search the entire community about keyword "wm8962", and found nothing useful. could some one give me a hint or suggestion what I should check?

p.s: in order to using alsamixer, there is a /etc/asound.conf:

/********************************************************************/

defaults.pcm.rate_converter "linear"

pcm.dmix_48000  {

        type dmix

        ipc_key 5778292

        ipc_key_add_uid false

        ipc_perm 0666

        slave {

                pcm "hw:0,0"

                period_time 10000

                buffer_time 512000

                format S16_LE

                rate 48000

        }

}

pcm.dsnoop_48000  {

        type dsnoop

        ipc_key 5778293

        ipc_key_add_uid false

        ipc_perm 0666

        slave{

                pcm "hw:0,0"

                period_time 10000

                buffer_time 512000

                format S16_LE

                rate 48000

        }

}

pcm.asymed {

        type asym

        playback.pcm "dmix_48000"

        capture.pcm "dsnoop_48000"

}

pcm.dsp0 {

        type plug

        slave.pcm "asymed"

}

pcm.!default {

        type plug

        route_policy "average"

        slave.pcm "asymed"

}

ctl.dmixer {

        type hw

        card 0

}

/********************************************************************/

not sure is this file related to this issue.

[igorpadykov]

Hi Wally

this issue and wm8962 error is well known (see link below)

and caused by power-up issues. So it make sense check board power-up

sequence.

http://comments.gmane.org/gmane.linux.alsa.devel/109219

Best regards

chip

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[wallyyeh]

After a lot of code review and try, I merge some code from linux-3.0.101 and 3.10.17-GA. now the sound works fine.

the patches file is in attach, hope this will be helpful for someone who stick to SDK_3.0.35_4.1.0-GA.

[wallyyeh]

Hi, chipexpert:

    thanks for reply, but the patch you post seems like for SDK_3.10.17? our product is for sale now, and it is based on old SDK_3.0.35_4.1.0_GA.

    In the kernel-3.0.35/sound/soc/codecs/wm8962.c, there's no function named "wm8962_runtime_resume", could you suggest me which part should modification ?

Wally

[igorpadykov]

Hi Wally

Please post this to meta-fsl-arm mailing list, so that someone familiar with wm8962 could try to assist you.

https://lists.yoctoproject.org/listinfo/meta-freescale

Best regards

chip