Re: [alsa-devel] Listing up to 8 PCM devices

At Wed, 19 Nov 2008 08:19:21 +0000 (UTC), Gregoire ETIENNE wrote:

Hi,

I'm currently writting a driver with up to 8 pcm devices, so I turned on "Dynamic device file minor numbers" option. But when I try to list devices through aplay or a record (which are calling ioctl with cmd SNDRV_CTL_IOCTL_PCM_NEXT_DEVICE) I can only list devices from 0 to 7. This is due to this code :

linux/sound/core/pcm.c l.64

case SNDRV_CTL_IOCTL_PCM_NEXT_DEVICE: { int device;

	if (get_user(device, (int __user *)arg))
		return -EFAULT;
	mutex_lock(&register_mutex);
	device = device < 0 ? 0 : device + 1;
	while (device < SNDRV_PCM_DEVICES) {
		if (snd_pcm_search(card, device))
			break;
		device++;
	}
	if (device == SNDRV_PCM_DEVICES)
		device = -1;
	mutex_unlock(&register_mutex);
	if (put_user(device, (int __user *)arg))
		return -EFAULT;
	return 0;
}

---

because SNDRV_PCM_DEVICES is defined to 8 and do not change even if I selected "Dynamic device file minor numbers" option.

Is there anything I missed ?

The definition of SNDRV_PCM_DEVICES was changed depending on CONFIG_SND_DYNAMIC_MINORS in the recent version. I guess you are referring to an old version.

Takashi