RE: [BUG REPORT] usb: dwc3: Bug while setting the USB transfer bandwidth on UVC gadget driver

[Felipe Balbi <balbi@kernel.org>]

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Hi,

"Chow, Watson" <Watson.Chow@Avnet.com> writes:
>>>>> 3. You suggest me to try on kernel v5.12 or the latest v5.13-rc. It looks not
>>>>> easy in my side to upgrade the kernel version. It would affect those other 
>>>>> device drivers I'm currently using. So, do you think there's any short cut 
>>>>> to fix this problem under my current kernel version - v5.4?
>>>>
>>>>In that case, you need to ask for support from whoever forces you to
>>>>stay with such an old kernel. I believe that would be Xilinx.
>>>
>>> I have a thought to back port those changes around the dwc3 and gadget driver
>>> from the latest kernel version to my kernel (v5.4). Do you think this is 
>>> feasible?
>>
>>should be, but it's likely quite a bit of work:
>>
>>$ git rev-list --count v5.4..linus/master -- drivers/usb/dwc3/
>>257
>>
>
> Upgraded the kernel version to 5.9, I can set the g_webcam module pararmeters
> as follow (for max bandwidth):
>
> streaming_maxpacket=3072
> streaming_maxburst=15
> streaming_interval=1
>
> Data transfer with above setting is working now - tested with dummy data
> generator in the uvc-gadget app.
>
> This concludes that kernel 5.4 is too old for DWC3 and UVC gadget driver
> in high bandwidth usage

Cool, thanks for letting me know :-)

-- 
balbi

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