[alsa-devel] Support for DSD streams

[Daniel Mack]

On 24.03.2013 02:33, Andreas Koch wrote:
> Hi Daniel,
> 
> At 11:43 AM 3/23/2013, Daniel Mack wrote:
>> Hi Andreas,
>>
>> On 23.03.2013 18:35, Andreas Koch wrote:
>>>> Yes, understood. The thing is just that we shouldn't break exising
>>>> solutions that already rely on this "bandaid".
>>>
>>> You wouldn't break any existing solution based on DoP, because that
>>> solution is dealt with in the application on one side and the DAC on
>>> the other side. The driver and USB transfer both think it is PCM data
>>> that is being sent.
>>
>> Well, that was exactly the problem with your device. With the driver as
>> it was, it exposed a PCM interface which is 16-bit wide, and that was
>> picked by ALSA when playing 16-bit material (because ALSA takes whatever
>> is offered by the hardware natively).
> 
> Not quite - the 16-bit wide interface offered by my DAC is not PCM, 
> but raw data.

For the correct quirks handling, I'd need to know whether all products
with your vendor ID are DSD capable on alt interface settings > 1. Is
that assumption correct or should I narrow it down to the product ID of
the MPD-3?


Thanks,
Daniel