At Sun, 17 Mar 2013 20:07:23 +0800, Daniel Mack wrote: > > 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. Thanks, applied to for-next branch. The remaining question is which PCM format is suitable for the raw data. SND_PCM_FORMAT_SPECIAL should be OK, it won't regress at least, as no apps support this format. Takashi > > > Thanks, > Daniel > > > 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(-) > > -- > 1.7.10.4 > _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
