diff options
| author | Takashi Iwai <tiwai@suse.de> | 2017-08-16 14:18:37 +0200 |
|---|---|---|
| committer | Takashi Iwai <tiwai@suse.de> | 2017-08-17 17:52:16 +0200 |
| commit | 0f174b3525a43bd51f9397394763925e0ebe7bc7 (patch) | |
| tree | f13262060f55267e5740e1cea1ad979e36813f4a /sound | |
| parent | ALSA: usb-audio: Apply sample rate quirk to Sennheiser headset (diff) | |
| download | linux-0f174b3525a43bd51f9397394763925e0ebe7bc7.tar.xz linux-0f174b3525a43bd51f9397394763925e0ebe7bc7.zip | |
ALSA: usb-audio: Add mute TLV for playback volumes on C-Media devices
C-Media devices (at least some models) mute the playback stream when
volumes are set to the minimum value. But this isn't informed via TLV
and the user-space, typically PulseAudio, gets confused as if it's
still played in a low volume.
This patch adds the new flag, min_mute, to struct usb_mixer_elem_info
for indicating that the mixer element is with the minimum-mute volume.
This flag is set for known C-Media devices in
snd_usb_mixer_fu_apply_quirk() in turn.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=196669
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'sound')
| -rw-r--r-- | sound/usb/mixer.c | 2 | ||||
| -rw-r--r-- | sound/usb/mixer.h | 1 | ||||
| -rw-r--r-- | sound/usb/mixer_quirks.c | 6 |
3 files changed, 9 insertions, 0 deletions
diff --git a/sound/usb/mixer.c b/sound/usb/mixer.c index 082736c539bc..e630813c5008 100644 --- a/sound/usb/mixer.c +++ b/sound/usb/mixer.c @@ -542,6 +542,8 @@ int snd_usb_mixer_vol_tlv(struct snd_kcontrol *kcontrol, int op_flag, if (size < sizeof(scale)) return -ENOMEM; + if (cval->min_mute) + scale[0] = SNDRV_CTL_TLVT_DB_MINMAX_MUTE; scale[2] = cval->dBmin; scale[3] = cval->dBmax; if (copy_to_user(_tlv, scale, sizeof(scale))) diff --git a/sound/usb/mixer.h b/sound/usb/mixer.h index 3417ef347e40..2b4b067646ab 100644 --- a/sound/usb/mixer.h +++ b/sound/usb/mixer.h @@ -64,6 +64,7 @@ struct usb_mixer_elem_info { int cached; int cache_val[MAX_CHANNELS]; u8 initialized; + u8 min_mute; void *private_data; }; diff --git a/sound/usb/mixer_quirks.c b/sound/usb/mixer_quirks.c index e3d1dec48ee4..e1e7ce9ab217 100644 --- a/sound/usb/mixer_quirks.c +++ b/sound/usb/mixer_quirks.c @@ -1878,6 +1878,12 @@ void snd_usb_mixer_fu_apply_quirk(struct usb_mixer_interface *mixer, if (unitid == 7 && cval->control == UAC_FU_VOLUME) snd_dragonfly_quirk_db_scale(mixer, cval, kctl); break; + /* lowest playback value is muted on C-Media devices */ + case USB_ID(0x0d8c, 0x000c): + case USB_ID(0x0d8c, 0x0014): + if (strstr(kctl->id.name, "Playback")) + cval->min_mute = 1; + break; } } |