From: John S. Gruber Date: Sun, 27 Dec 2009 17:19:58 +0000 (-0500) Subject: ALSA: usb-audio: relax urb data align. restriction HVR-950Q and HVR-850 only X-Git-Tag: v2.6.34-rc1~243^2~2^2~13^2~20 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=98e89f606c38a310a20342f90e0c453e6afadf18;p=pandora-kernel.git ALSA: usb-audio: relax urb data align. restriction HVR-950Q and HVR-850 only Addressing audio quality problem. In sound/usb/usbaudio.c, for the Hauppage HVR-950Q and HVR-850 only, change retire_capture_urb to allow transfers on audio sub-slot boundaries rather than audio slots boundaries. With these devices the left and right channel samples can be split between two different urbs. Throwing away extra channel samples causes a sound quality problem for stereo streams as the left and right channels are swapped repeatedly, perhaps many times per second. Urbs unaligned on sub-slot boundaries are still truncated to the next lowest stride (audio slot) to retain synchronization on samples even though left/right channel synchronization may be lost in this case. Detect the quirk using a case statement in snd_usb_audio_probe. BugLink: https://bugs.launchpad.net/ubuntu/+bug/495745 Signed-off-by: John S. Gruber Signed-off-by: Takashi Iwai --- Reading git-diff-tree failed