ALSA: usb: Add quirk for 192KHz recording on E-Mu devices
authorCalvin Owens <jcalvinowens@gmail.com>
Sat, 13 Apr 2013 03:33:59 +0000 (22:33 -0500)
committerTakashi Iwai <tiwai@suse.de>
Sat, 13 Apr 2013 08:58:03 +0000 (10:58 +0200)
commit1539d4f82ad534431cc67935e8e442ccf107d17d
treeedb34bea8a89d757f14bbf099329285c036f7279
parentb26b51166848758d740ab638fc27789228a51c97
ALSA: usb: Add quirk for 192KHz recording on E-Mu devices

When recording at 176.2KHz or 192Khz, the device adds a 32-bit length
header to the capture packets, which obviously needs to be ignored for
recording to work properly.

Userspace expected:  L0 L1 L2 R0 R1 R2
...but actually got: R2 L0 L1 L2 R0 R1

Also, the last byte of the length header being interpreted as L0 of
the first sample caused spikes every 0.5ms, resulting in a loud 16KHz
tone (about the highest 'B' on a piano) being present throughout
captures.

Tested at all sample rates on an E-Mu 0404USB, and tested for
regressions on a generic USB headset.

Signed-off-by: Calvin Owens <jcalvinowens@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
sound/usb/card.h
sound/usb/pcm.c
sound/usb/quirks.c
sound/usb/stream.c
This page took 0.026395 seconds and 5 git commands to generate.