[alsa-devel] [PATCH 0/3] ALSA: snd-usb: Some small fixes to make Playback Design products work
zonque at gmail.com
Sun Mar 17 13:07:23 CET 2013
Thanks to Andreas, I got my hands on a Playback Design MPD-3 and hacked
up some small hanges necessary to make it fully work with snd-usb.
The device reports 0x80000000 in the bmFormats field of two of three of
its alternate settings, which wrongly made the driver believe it's a
usual PCM endpoint (actually due to a fix-up fallback). However, bit 31
of this mask in fact denotes 'raw data'.
The effect of this issue is that in addition to the first altsetting with
a bit depth of 24, the driver exposed 8-bit and 16-bit native audio
formats on the raw data endpoints, which do not work as expected.
Also, those devices need a 50ms delay after switching the USB interface.
Daniel Mack (3):
ALSA: snd-usb: handle the bmFormats field as unsigned int
ALSA: snd-usb: handle raw data format of UAC2 devices
ALSA: snd-usb: add delay quirk for "Playback Design" products
include/linux/usb/audio-v2.h | 2 ++
sound/usb/format.c | 20 ++++++++++++--------
sound/usb/format.h | 2 +-
sound/usb/pcm.c | 7 +++++++
sound/usb/stream.c | 2 +-
5 files changed, 23 insertions(+), 10 deletions(-)
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