Audio output low volume

    Hello


    I started checking the PicocomA7 modul on the evaluation board for some basic tests.


    One part was the audio output and input which failed due to a very low volume.


    Using arecord and an external audio source seems to be ok.

    Running aplay with a well known wave file shows nearly nothing on the output pins.


    As it's the same audio codec like the PicocomA5 may be its the same issue like it was few years ago.

    See Audio output low volume


    Best regards

    Hi,


    do you have changed the software on your evaluation board, if yes which release do you are using?


    Can you send me the debug log from the board and also the commands which you have used?


    Your F&S Support Team

    F&S Elektronik Systeme GmbH
    As this is an international forum, please try to post in English.
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    Hi,


    I can´t reproduce the issue which you have mentioned. Can you please do two more tests.


    • Run command "speakertest -c 2 -t wav". How is the sound now?
    • Can you install the release software and do the tests again. Is there any change?

    Your F&S Support Team

    F&S Elektronik Systeme GmbH
    As this is an international forum, please try to post in English.
    Da dies ein internationales Forum ist, bitten wir darum, Beiträge möglichst in Englisch zu verfassen.

    I have to apologise my start posting.


    The problem is not the PicocomA7, it's just our application software which wont work as expected.

    The aplay/arecord runs fine when using the correct parameter.


    We must checkout the difference between PicocomA5 and A7 ALSA regarding settings and fix our software.


    Sorry for trouble - best regards.

    Hi,


    thanks for the feedback. Maybe the alsa config needs to be setup.


    Your F&S Support Team

    F&S Elektronik Systeme GmbH
    As this is an international forum, please try to post in English.
    Da dies ein internationales Forum ist, bitten wir darum, Beiträge möglichst in Englisch zu verfassen.

    The problem is in the kernel. At least the behaviour has changed.

    The codec makes a delay of 400ms in snd_pcm_prepare().

    This is much too long, and delays and disturbs the audio output.


    One solution is described at https://community.nxp.com/t5/i…l5000-latency/td-p/857730


    My solution is the parameter no-standby from the device tree file

    If no-standby is set, the codec is always powered up. And the 400ms delay disappears.


    Index: arch/arm/boot/dts/picocoma7.dts

    ===================================================================

    --- arch/arm/boot/dts/picocoma7.dts (revision 35)

    +++ arch/arm/boot/dts/picocoma7.dts (working copy)

    @@ -502,6 +502,7 @@

    compatible = "fsl,sgtl5000";

    reg = <0x0a>;

    mono2both;

    + no-standby;

    clocks = <&clks IMX6UL_CLK_SAI1>;

    VDDA-supply = <&reg_sgtl5000_vdda>;

    VDDIO-supply = <&reg_sgtl5000_vddio>;