Files
linux/sound/usb/mixer_maps.c
Jiri Jaburek 6c300cb1fb ALSA: usb-audio: extend KEF X300A FU 10 tweak to Arcam rPAC
commit d70a1b9893 upstream.

The Arcam rPAC seems to have the same problem - whenever anything
(alsamixer, udevd, 3.9+ kernel from 60af3d037e, ..) attempts to
access mixer / control interface of the card, the firmware "locks up"
the entire device, resulting in
  SNDRV_PCM_IOCTL_HW_PARAMS failed (-5): Input/output error
from alsa-lib.

Other operating systems can somehow read the mixer (there seems to be
playback volume/mute), but any manipulation is ignored by the device
(which has hardware volume controls).

Signed-off-by: Jiri Jaburek <jjaburek@redhat.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-16 06:59:50 -08:00

13 KiB