HummingBoard Pulse & i.MX8M Plus missing audio devices

NXP i.MX8M Plus
1

Hi,

I’m missing the audio devices on my HummingBoard Pulse & i.MX8M Plus.
I’m using the yocto gatesgarth imx8mpsolidrun image provided by solidrun.
aplay -L only display the null and die pulse audio interface, no hardware audio interfaces.

I found some messages around the audio interfaces in dmesg:

[    1.827337] fsl-sai 30c30000.sai: failed to get bus clock: -517
[    1.835206] fsl-easrc 30c90000.easrc: failed to get mem clock
[    1.843562] imx-cdnhdmi sound-hdmi: failed to find SAI platform device
[    1.850122] imx-cdnhdmi: probe of sound-hdmi failed with error -22

[    6.213189] wm8904 1-001a: supply DCVDD not found, using dummy regulator
[    6.218952] basler_camera_driver_vvcam: loading out-of-tree module taints kernel.
[    6.222899] at24 0-0050: 256 byte 24c02 EEPROM, writable, 16 bytes/write
[    6.223725] wm8904 1-001a: supply DBVDD not found, using dummy regulator
[    6.223769] wm8904 1-001a: supply AVDD not found, using dummy regulator
[    6.223807] wm8904 1-001a: supply CPVDD not found, using dummy regulator
[    6.223845] wm8904 1-001a: supply MICVDD not found, using dummy regulator
[    6.230431] wm8904 1-001a: Failed to read ID register: -6

Complete dmesg output:https://pastebin.com/rZ5BkNmf
Did you have any ideas what could be the problem

Best regards, Jonas

2

Support for this hardware has been added in our upcoming hardknott yocto release, and should be able to be integrated into gategarth as well. The kernel repository is here GitHub - SolidRun/linux-stable at lf-5.10.72-2.2.0-sr and the meta layer and official image will be out this week.

3

I still get into trouble with audio playback using your pre-built image, imx8mp_yocto_hardknott-5.10.72-2.2.0/imx-image-full-imx8mpsolidrun-20220225.rootfs.wic.bz2. wm8904 is found by gst-device-monitor-1.0

Device found:

        name  : wm8904-audio
        class : Audio/Sink
        caps  : audio/x-raw, format={ (string)S32LE, (string)S24_32LE, (string)S16LE }, layout=interleaved, rate=[ 8000, 96000 ], channels=2, channel-mask=0x0000000000000003
        properties:
                device.api = alsa
                device.class = sound
                alsa.card = 1
                alsa.card_name = wm8904-audio
                alsa.driver_name = wm8904-audio
                alsa.name = wm8904-audio
                alsa.id = wm8904audio
                alsa.mixername = ""
                alsa.components = ""
        gst-launch-1.0 ... ! alsasink device="hw:1\,0"

but the process of playing audio test is failed as below.

root@imx8mpsolidrun:~# gst-launch-1.0 audiotestsrc ! alsasink device="hw:1\,0"
Setting pipeline to PAUSED ...
Pipeline is PREROLLING ...
ERROR: from element /GstPipeline:pipeline0/GstAlsaSink:alsasink0: Could not get/set settings from/on resource.
Additional debug info:
../git/ext/alsa/gstalsasink.c(658): set_hwparams (): /GstPipeline:pipeline0/GstAlsaSink:alsasink0:
Unable to set hw params for playback: Invalid argument
ERROR: pipeline doesn't want to preroll.
ERROR: from element /GstPipeline:pipeline0/GstAlsaSink:alsasink0: Could not get/set settings from/on resource.
Setting pipeline to NULL ...
Additional debug info:
../git/ext/alsa/gstalsasink.c(982): gst_alsasink_prepare (): /GstPipeline:pipeline0/GstAlsaSink:alsasink0:
Setting of hwparams failed: Invalid argument
ERROR: pipeline doesn't want to preroll.
Freeing pipeline ...

In addition, pactl doesn’t find wm8904.

root@imx8mpsolidrun:~# pactl list sinks
Sink #0
        State: SUSPENDED
        Name: alsa_output.platform-sound-hdmi.stereo-fallback
        Description: Built-in Audio Stereo
        Driver: module-alsa-card.c
        Sample Specification: s32le 2ch 44100Hz
        Channel Map: front-left,front-right
        Owner Module: 6
        Mute: no
        Volume: front-left: 65536 / 100% / 0.00 dB,   front-right: 65536 / 100% / 0.00 dB
                balance 0.00
        Base Volume: 65536 / 100% / 0.00 dB
        Monitor Source: alsa_output.platform-sound-hdmi.stereo-fallback.monitor
        Latency: 0 usec, configured 0 usec
        Flags: HARDWARE DECIBEL_VOLUME LATENCY
        Properties:
                alsa.resolution_bits = "24"
                device.api = "alsa"
                device.class = "sound"
                alsa.class = "generic"
                alsa.subclass = "generic-mix"
                alsa.name = "imx8 hdmi i2s-hifi-0"
                alsa.id = "imx8 hdmi i2s-hifi-0"
                alsa.subdevice = "0"
                alsa.subdevice_name = "subdevice #0"
                alsa.device = "0"
                alsa.card = "0"
                alsa.card_name = "audio-hdmi"
                alsa.long_card_name = "audio-hdmi"
                alsa.driver_name = "snd_soc_imx_cdnhdmi"
                device.bus_path = "platform-sound-hdmi"
                sysfs.path = "/devices/platform/sound-hdmi/sound/card0"
                device.form_factor = "internal"
                device.string = "hw:0"
                device.buffering.buffer_size = "35264"
                device.buffering.fragment_size = "8816"
                device.access_mode = "mmap"
                device.profile.name = "stereo-fallback"
                device.profile.description = "Stereo"
                device.description = "Built-in Audio Stereo"
                module-udev-detect.discovered = "1"
                device.icon_name = "audio-card"
        Ports:
                analog-output: Analog Output (type: Analog, priority: 9900, availability unknown)
        Active Port: analog-output
        Formats:
                pcm

Is there any article such as Audio Quick Start in your wiki?