static int usb_chmap_ctl_info(struct snd_kcontrol *kcontrol,
			      struct snd_ctl_elem_info *uinfo)
{
	struct snd_pcm_chmap *info = snd_kcontrol_chip(kcontrol);
	struct snd_usb_substream *subs = info->private_data;

	uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
	uinfo->count = subs->channels_max;
	uinfo->value.integer.min = 0;
	uinfo->value.integer.max = SNDRV_CHMAP_LAST;
	return 0;
}
Unknown