[alsa-devel] [Linux-kernel] [PATCH v5 2/7] ASoC: tegra: Allow 24bit and 32bit samples

[Dmitry Osipenko]

06.01.2020 22:00, Ben Dooks пишет:
> On 05/01/2020 10:53, Ben Dooks wrote:
>>
>>
>> On 2020-01-05 01:48, Dmitry Osipenko wrote:
>>> 05.01.2020 03:04, Ben Dooks пишет:
>>>> [snip]
>>>>
>>>> I've just gone through testing.
>>>>
>>>> Some simple data tests show 16 and 32-bits work.
>>>>
>>>> The 24 bit case seems to be weird, it looks like the 24-bit expects
>>>> 24 bit samples in 32 bit words. I can't see any packing options to
>>>> do 24 bit in 24 bit, so we may have to remove 24 bit sample support
>>>> (which is a shame)
>>>>
>>>> My preference is to remove the 24-bit support and keep the 32 bit in.
>>>>
>>>
>>> Interesting.. Jon, could you please confirm that 24bit format isn't
>>> usable on T30?
>>
>> If there is an option of 24 packed into 32, then I think that would work.
>>
>> I can try testing that with raw data on Monday.
> 
> I need to check some things, I assumed 24 was 24 packed bits, it looks
> like the default is 24 in 32 bits so we may be ok. However I need to
> re-write my test case which assumed it was 24bits in 3 bytes (S24_3LE).
> 
> I'll follow up later,

Okay, the S24_3LE isn't supported by RT5640 codec in my case. I briefly
looked through the TRM doc and got impression that AHUB could re-pack
data stream into something that codec supports, but maybe it's a wrong
impression.