[alsa-devel] asoc device probing and dai question

Koul, Vinod vinod.koul at intel.com
Thu Dec 2 12:01:07 CET 2010


In our driver, the machine probe creates the soc-audio device. I am adding the 
codec and platform device in my soc-device. But the probe for the codec doesn't 
get called unless we add the cpu and codec dais in the machine probe. I saw the 
soc-core code and looks like it checks if cpu and codec dais are registerd if so 
then only proceeds and calls the codec probe.

So should I continue to register the dai for both cpu and codec in machine 
probe. I didn't see other driver in soc/ doing this, so did I miss something.

In m/c driver... (the m/c driver probe is called by kernel when it finds this 
device, and I register it as a platform device)

/* Audio machine driver */
static struct snd_soc_card snd_soc_intelmid_card = {
        .name = "intel_mid_sound_card",
        .platform = &intelmid_soc_platform,
        .dai_link = intelmid_msic_dai,
        .num_links = 1,

/* Audio subsystem */
static struct snd_soc_device intelmid_snd_devdata = {
        .card = &snd_soc_intelmid_card,
        .codec_dev = &intel_msic_codec,
int __devinit snd_intelmid_mc_probe(struct platform_device *pdev)
        int ret_val;

        snd_printk(KERN_DEBUG "snd_intelmad_probe called\n");

        ret_val = snd_soc_register_dais(mid_bsp_dai, ARRAY_SIZE(mid_bsp_dai));
        ret_val = snd_soc_register_dais(intel_msic_dais, ARRAY_SIZE(intel_msic_dais));

        intelmid_snd_device = platform_device_alloc("soc-audio", -1);
        if (!intelmid_snd_device) {
                snd_printk(KERN_ERR "Platform device allocation failed\n");
                return -ENOMEM;

        platform_set_drvdata(intelmid_snd_device, &intelmid_snd_devdata);
        intelmid_snd_devdata.dev = &intelmid_snd_device->dev;

        ret_val = platform_device_add(intelmid_snd_device);
        if (ret_val) {
                snd_printk(KERN_ERR "Unable to add platform device\n");
        return ret_val;

In platform init (note I don't have probe for platform)
static int __init intel_mid_soc_platform_init(void)
        snd_printk(KERN_DEBUG "intel_mid_soc_platform_init called\n");
        return snd_soc_register_platform(&intelmid_soc_platform);


More information about the Alsa-devel mailing list