3 files changed, 11 insertions, 0 deletions

diff --git a/sound/usb/Kconfig b/sound/usb/Kconfig
index de9408b83f75..e05a86b7c0da 100644
--- a/sound/usb/Kconfig
+++ b/sound/usb/Kconfig
@@ -14,6 +14,7 @@ config SND_USB_AUDIO
         select SND_HWDEP
         select SND_RAWMIDI
         select SND_PCM
+        select BITREVERSE
         help
           Say Y here to include support for USB audio and USB MIDI
           devices.
diff --git a/sound/usb/mixer.c b/sound/usb/mixer.c
index 44b0ba4feab3..1bed780e21d9 100644
--- a/sound/usb/mixer.c
+++ b/sound/usb/mixer.c
@@ -883,6 +883,7 @@ static void volume_control_quirks(struct usb_mixer_elem_info *cval,
                 }
                 break;
 
+        case USB_ID(0x046d, 0x0807): /* Logitech Webcam C500 */
         case USB_ID(0x046d, 0x0808):
         case USB_ID(0x046d, 0x0809):
         case USB_ID(0x046d, 0x081b): /* HD Webcam c310 */
diff --git a/sound/usb/mixer_maps.c b/sound/usb/mixer_maps.c
index 32af6b741ef5..d1d72ff50347 100644
--- a/sound/usb/mixer_maps.c
+++ b/sound/usb/mixer_maps.c
@@ -328,6 +328,11 @@ static struct usbmix_name_map gamecom780_map[] = {
         {}
 };
 
+static const struct usbmix_name_map kef_x300a_map[] = {
+        { 10, NULL }, /* firmware locks up (?) when we try to access this FU */
+        { 0 }
+};
+
 /*
  * Control map entries
  */
@@ -419,6 +424,10 @@ static struct usbmix_ctl_map usbmix_ctl_maps[] = {
                 .id = USB_ID(0x200c, 0x1018),
                 .map = ebox44_map,
         },
+        {
+                .id = USB_ID(0x27ac, 0x1000),
+                .map = kef_x300a_map,
+        },
         { 0 } /* terminator */
 };