| From: Takashi Iwai <tiwai@suse.de> |
| Date: Tue, 24 Apr 2018 11:11:48 +0200 |
| Subject: ALSA: usb-audio: Skip broken EU on Dell dock USB-audio |
| |
| commit 1d8d6428d1da642ddd75b0be2d1bb1123ff8e017 upstream. |
| |
| The Dell Dock USB-audio device with 0bda:4014 is behaving notoriously |
| bad, and we have already applied some workaround to avoid the firmware |
| hiccup. Yet we still need to skip one thing, the Extension Unit at ID |
| 4, which doesn't react correctly to the mixer ctl access. |
| |
| Bugzilla: https://bugzilla.suse.com/show_bug.cgi?id=1090658 |
| Signed-off-by: Takashi Iwai <tiwai@suse.de> |
| Signed-off-by: Ben Hutchings <ben@decadent.org.uk> |
| --- |
| sound/usb/mixer_maps.c | 3 +++ |
| 1 file changed, 3 insertions(+) |
| |
| --- a/sound/usb/mixer_maps.c |
| +++ b/sound/usb/mixer_maps.c |
| @@ -346,8 +346,11 @@ static struct usbmix_name_map bose_compa |
| /* |
| * Dell usb dock with ALC4020 codec had a firmware problem where it got |
| * screwed up when zero volume is passed; just skip it as a workaround |
| + * |
| + * Also the extension unit gives an access error, so skip it as well. |
| */ |
| static const struct usbmix_name_map dell_alc4020_map[] = { |
| + { 4, NULL }, /* extension unit */ |
| { 16, NULL }, |
| { 19, NULL }, |
| { 0 } |