ALSA: usb-audio: Add private_data pointer to usb_mixer_elem_info

Add a private_data pointer to usb_mixer_elem_info to allow other mixer
implementations to extend the structure as necessary.

Signed-off-by: Chris J Arges <chris.j.arges@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/usb/mixer.h b/sound/usb/mixer.h
index 2c7b9c9c2aa642eea27f6d533c348e0043986b62..7423f998cfb5bfc2f74ea2c592b8b300bc08f176 100644 (file)
--- a/sound/usb/mixer.h
+++ b/sound/usb/mixer.h
@@ -53,6 +53,7 @@ struct usb_mixer_elem_info {
        int cached;
        int cache_val[MAX_CHANNELS];
        u8 initialized;
+       void *private_data;
 };
 
 int snd_usb_create_mixer(struct snd_usb_audio *chip, int ctrlif,