On Mon, Aug 25, 2014 at 2:57 PM, Daniel Mack <daniel@xxxxxxxxxx> wrote:
> On 08/25/2014 11:23 AM, Jassi Brar wrote:
>> On Mon, Aug 25, 2014 at 2:14 PM, Daniel Mack <daniel@xxxxxxxxxx> wrote:
>
>>> The easiest is probably really to just calculate correct packet sizes
>>> and stick to them. After all, the actual clock is really arbitrary, we
>>> just have to pick something that is in the range of the sample rate.
>>>
>>> I'll cook up an alternative patch and do some tests with Sebastian off-list.
>>>
>> How about configuring bInterval and wMaxPacketSize to get the desired rate?
>>
>> For ex, 48KHz/2/S16, we need 192bytes/millisec. So we set bInterval=1
>> (or 4 for HS) and wMaxPacketSize=192 for that configuration. For
>> 44.1KHz/2/S16 we need 176.4bytes/millisec, so we set
>> wMaxPacketSize=178 and send packets of length in {176, 176, 176,
>> 176,178} pattern.
>
> Yes, something like that. But you can't modify wMaxPacketSize in
> accordance to the sample rate and format, but just send short packets.
>
We can't change rate once the f_uac2 module is loaded. So
wMaxPacketSize changes only across module loads.
Cheers,
-jassi
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