Re: [PATCH] usb: gadget: f_uac2: fixed EP-IN wMaxPacketSize

[Pavel Hofman <pavel.hofman@ivitera.com>]

Hi Greg,

Dne 24. 09. 21 v 10:20 Greg KH napsal(a):
> On Fri, Sep 24, 2021 at 10:00:27AM +0200, Pavel Hofman wrote:
>> Async feedback patches broke enumeration on Windows 10 previously fixed
>> by commit 789ea77310f0 ("usb: gadget: f_uac2: always increase endpoint
>> max_packet_size by one audio slot").
>>
>> While the existing calculation for EP OUT capture for async mode yields
>> size+1 frame due to uac2_opts->fb_max > 0, playback side lost the +1
>> feature.  Therefore the +1 frame addition must be re-introduced for
>> playback. Win10 enumerates the device only when both EP IN and EP OUT
>> max packet sizes are (at least) +1 frame.
>>
>> Signed-off-by: Pavel Hofman <pavel.hofman@ivitera.com>
>> Tested-by: Henrik Enquist <henrik.enquist@gmail.com>
>> Tested-by: Jack Pham <jackp@codeaurora.org>
>> ---
>>   drivers/usb/gadget/function/f_uac2.c | 14 ++++++++++----
>>   1 file changed, 10 insertions(+), 4 deletions(-)
> 
> What commit does this fix?
> 
> Should it go to stable kernel(s)?

It's the same effort direction as commit 
https://kernel.googlesource.com/pub/scm/linux/kernel/git/gregkh/usb/+/f5dfd98a80ff8d50cf4ae2820857d7f5a46cbab9 
which you added to your usb-linus branch 
https://kernel.googlesource.com/pub/scm/linux/kernel/git/gregkh/usb/+log/refs/heads/usb-linus/drivers/usb/gadget/function 
Therefore I would say usb-linus.

Please what are your rules for usb-linus and usb-next? There are some 
different commits in usb-next and usb-linus changing the same file - 
f_uac2.c . Likely not, but a conflict could potentially occur. I do not 
know what head to rebase my further patches which also make larger 
changes to that file.

Thanks a lot for explanation,

Pavel.