Re: [REGRESSION] "dwc2: gadget: fix TX FIFO size and address initialization" breaks "adb logcat" on hikey

From: John Youn
Date: Thu Oct 06 2016 - 14:26:50 EST


On 10/5/2016 11:33 PM, John Stultz wrote:
> Hey folks,
> So I've run into some trouble that I've narrowed down to commit
> aa381a7259c3 ("usb: dwc2: gadget: fix TX FIFO size and address
> initialization").
>
> After booting up android on HiKey, if I run "adb logcat", I get about
> a page of logs and then I get disconnected. On the device side, I see
> the following in dmesg:
>
> [ 35.652076] dwc2 f72c0000.usb: dwc2_hsotg_ep_sethalt(ep
> ffffffc078a4c218 ep1in, 0)
> [ 35.660334] dwc2 f72c0000.usb: dwc2_hsotg_ep_sethalt(ep
> ffffffc078a4c018 ep1out, 0)
>
> After which if I stop adbd I see:
>
> [ 99.471363] dwc2 f72c0000.usb: dwc2_hsotg_ep_stop_xfr: timeout flushing fifos
>
> and if I then restart adbd on the device it will sometimes work, but not always.
>
> Reverting
> ba48eab8866c ("usb: dwc2: gadget: change variable name to more meaningful")
> and
> aa381a7259c3 ("usb: dwc2: gadget: fix TX FIFO size and address initialization")
>
> makes things work again.
>
> Any thoughts as to what might be going wrong here? I'd be happy to
> help debug things.
>
> thanks
> -john
>


Hi John,

Yup. I've already submitted patches to revert these last week, to be
applied sometime during the 4.9-rc cycle. We're working on a more
robust fix for the FIFOs too.

Regards,
John