diff --git a/sound/usb/mixer.c b/sound/usb/mixer.c index 082736c539bc14eec73a1afad11e2a3cd5577d89..e630813c5008627d50e41637e03eeaf8ef2bf0c3 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 3417ef347e40432482b84de271a3bb98c8724297..2b4b067646ab099653fe7ea79d9af1570e2971f6 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 e3d1dec48ee49f21d4efe4627fc3c264d76fcfe2..e1e7ce9ab217f6f716fc95da5d1544279c0d1b75 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; } }