ALSA: usb-audio: Set the Control Selector to SU_SELECTOR_CONTROL for UAC2
Specified in section 5.2.5.6.1 of the USB Audio Class 2.0 definition.
Solves the following error for C-Media 6632A (Asus Xonar U7):
[ 8219.676164] cannot get ctl value: req = 0x81, wValue = 0x0, wIndex = 0x1400, type = 3
Signed-off-by: Johan Rastén <johan@oljud.se>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/usb/mixer.c b/sound/usb/mixer.c
index 2e4a9db..6e354d3 100644
--- a/sound/usb/mixer.c
+++ b/sound/usb/mixer.c
@@ -2033,10 +2033,11 @@
cval->res = 1;
cval->initialized = 1;
- if (desc->bDescriptorSubtype == UAC2_CLOCK_SELECTOR)
- cval->control = UAC2_CX_CLOCK_SELECTOR;
- else
+ if (state->mixer->protocol == UAC_VERSION_1)
cval->control = 0;
+ else /* UAC_VERSION_2 */
+ cval->control = (desc->bDescriptorSubtype == UAC2_CLOCK_SELECTOR) ?
+ UAC2_CX_CLOCK_SELECTOR : UAC2_SU_SELECTOR;
namelist = kmalloc(sizeof(char *) * desc->bNrInPins, GFP_KERNEL);
if (!namelist) {