tree 3ef678c2d8da68a9cc2fd34906a8cc177f6722ec
parent 94908a39ce971f25c3695c334d88eec4d2837428
author Anssi Hannula <anssi.hannula@iki.fi> 1384111445 +0200
committer Takashi Iwai <tiwai@suse.de> 1384186017 +0100

ALSA: usb: Fix wrong mapping of RLC and RRC channels

According to USB Audio spec v2 bits 25 and 26 of bmChannelConfig are
"Back Left of Center - BLC" and "Back Right of Center - BRC",
respectively.

They are currently assigned to ALSA channels BLC/BRC. However, the ALSA
BLC/BRC are actually the rather nonsensical "bottom left center" and
"bottom right center", so the channels will be assigned wrongly. The
comments in the USB code are also similarly wrong, so this is not
readily apparent without looking at the actual specification.

Fix the channel mapping by mapping bits 25 and 26 to RLC (Rear Left
Center) and RRC (Rear Right Center), respectively, instead.

Signed-off-by: Anssi Hannula <anssi.hannula@iki.fi>
Signed-off-by: Takashi Iwai <tiwai@suse.de>