ALSA: usb-audio: add new quirk type QUIRK_AUDIO_STANDARD_MIXER

This quirk type will let the driver assume that there is a standard
mixer on a given interface, or that a specific mixer quirks will handle
the device.

Signed-off-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

2 files changed, 17 insertions, 1 deletions

diff --git a/sound/usb/quirks.c b/sound/usb/quirks.c
index 2546dc808e43..2e969cbb393b 100644
--- a/sound/usb/quirks.c
+++ b/sound/usb/quirks.c
@@ -264,6 +264,20 @@ static int create_uaxx_quirk(struct snd_usb_audio *chip,
 }
 
 /*
+ * Create a standard mixer for the specified interface.
+ */
+static int create_standard_mixer_quirk(struct snd_usb_audio *chip,
+                                       struct usb_interface *iface,
+                                       struct usb_driver *driver,
+                                       const struct snd_usb_audio_quirk *quirk)
+{
+        if (quirk->ifnum < 0)
+                return 0;
+
+        return snd_usb_create_mixer(chip, quirk->ifnum, 0);
+}
+
+/*
  * audio-interface quirks
  *
  * returns zero if no standard audio/MIDI parsing is needed.
@@ -295,7 +309,8 @@ int snd_usb_create_quirk(struct snd_usb_audio *chip,
                 [QUIRK_AUDIO_STANDARD_INTERFACE] = create_standard_audio_quirk,
                 [QUIRK_AUDIO_FIXED_ENDPOINT] = create_fixed_stream_quirk,
                 [QUIRK_AUDIO_EDIROL_UAXX] = create_uaxx_quirk,
-                [QUIRK_AUDIO_ALIGN_TRANSFER] = create_align_transfer_quirk
+                [QUIRK_AUDIO_ALIGN_TRANSFER] = create_align_transfer_quirk,
+                [QUIRK_AUDIO_STANDARD_MIXER] = create_standard_mixer_quirk,
         };
 
         if (quirk->type < QUIRK_TYPE_COUNT) {
diff --git a/sound/usb/usbaudio.h b/sound/usb/usbaudio.h
index 32f2a97f2f14..1e79986b5777 100644
--- a/sound/usb/usbaudio.h
+++ b/sound/usb/usbaudio.h
@@ -84,6 +84,7 @@ enum quirk_type {
         QUIRK_AUDIO_FIXED_ENDPOINT,
         QUIRK_AUDIO_EDIROL_UAXX,
         QUIRK_AUDIO_ALIGN_TRANSFER,
+        QUIRK_AUDIO_STANDARD_MIXER,
 
         QUIRK_TYPE_COUNT
 };