Re: [PATCH v2 1/2 RESEND] usb: gadget: u_audio: pass channel counts explicitly

[kaf@nwlink.com]

On 2026-10-23 03:39, Francesco Lavra wrote:
> On Fri, 2026-10-16 at 09:25 -0700, Kyle Farrell wrote:
>> u_audio currently derives the channel count from the channel mask in
>> struct uac_params in several places.  Instead, pass the resolved count
>> explicitly, so the shared audio implementation does not depend on how
>> an individual USB audio function represents its channel configuration.
>> 
>> Initialize the new channel count fields from the existing channel 
>> masks.
>> This preserves generated descriptors and makes no change to 
>> user-visible
>> behavior.
>> 
>> Assisted-by: LLM
>> Signed-off-by: Kyle Farrell <kaf@nwlink.com>
>> ---
> ...
>> diff --git a/drivers/usb/gadget/function/u_audio.h
>> b/drivers/usb/gadget/function/u_audio.h
>> index 9512b8fccfaa..46e1d6b5ca4e 100644
>> --- a/drivers/usb/gadget/function/u_audio.h
>> +++ b/drivers/usb/gadget/function/u_audio.h
>> @@ -41,12 +41,14 @@ struct uac_fu_params {
>>  struct uac_params {
>>         /* playback */
>>         int p_chmask;   /* channel mask */
> 
> With these changes, the channel masks are no longer used in u_audio.c, 
> so
> we can remove them.
> 
>> +       unsigned int p_channels;        /* resolved number of channels 
>> */
>>         int p_srate;    /* rate in Hz */
>>         int p_ssize;    /* sample size */
>>         struct uac_fu_params p_fu;      /* Feature Unit parameters */
>>  
>>         /* capture */
>>         int c_chmask;   /* channel mask */
>> +       unsigned int c_channels;        /* resolved number of channels 
>> */
>>         int c_srate;    /* rate in Hz */
>>         int c_ssize;    /* sample size */
>>         struct uac_fu_params c_fu;      /* Feature Unit parameters */

Agreed, and thanks for taking a look. The resolved channel counts 
replace the channel masks.
I'll remove them in v3.