[alsa-devel] [PATCH v3 0/5] ALSA: snd-usb: add support for DSD

[Takashi Iwai]

At Wed, 17 Apr 2013 00:01:35 +0800,
Daniel Mack wrote:
> 
> In contrast to the first two approaches, this one keeps the userspace
> unaware of the actual transport on the bus.
> 
> More specifically, the DSD_U16_LE format may be implemented to actually
> send DOP samples to the device, depending on the quirks entries.
> 
> Also, as there is quite some confusion in both data file formats as
> well as hardware sample formats about whether to stuff the oldest bit
> in the MSB or the LSB of a byte, ALSA defines that now to be in the
> MSB, as far as the ALSA userspace layer is concerned. The driver
> learned functions to re-encode the bytes according to what the hardware
> supports.
> 
> I also wrote a very basic test tool which I published here:
> 
>   https://github.com/zonque/alsa-dsd-player

Maybe it'd be good to merge it into alsa-lib/test directory or
alsa-utils (or alsa-tools).


Takashi

> 
> 
> Thanks,
> Daniel
> 
> Daniel Mack (5):
>   ALSA: add DSD formats
>   ALSA: snd-usb: use ep->stride from urb callbacks
>   ALSA: snd-usb: add support for DSD DOP stream transport
>   ALSA: snd-usb: add support for bit-reversed byte formats
>   ALSA: snd-usb: add quirks handler for DSD streams
> 
>  include/sound/pcm.h         |    2 +
>  include/uapi/sound/asound.h |    4 +-
>  sound/core/pcm.c            |    2 +
>  sound/core/pcm_misc.c       |    8 +++
>  sound/usb/card.h            |    8 +++
>  sound/usb/endpoint.c        |    9 ++++
>  sound/usb/format.c          |    3 ++
>  sound/usb/pcm.c             |  118 ++++++++++++++++++++++++++++++++++++-------
>  sound/usb/quirks.c          |   28 ++++++++++
>  sound/usb/quirks.h          |    4 ++
>  10 files changed, 167 insertions(+), 19 deletions(-)
> 
> -- 
> 1.7.10.4
>