[RFCv1 0/8] Meson-8b and Meson-gxbb USB phy code re-structure

Anand Moon linux.amoon at gmail.com
Fri Jun 18 06:20:39 PDT 2021


Hi Martin,

Thanks for your review comments.
(some email id got messed up while sending these changes.)

On Fri, 18 Jun 2021 at 03:41, Martin Blumenstingl
<martin.blumenstingl at googlemail.com> wrote:
>
> Hi Anand,
>
> On Thu, Jun 17, 2021 at 9:42 PM Anand Moon <linux.amoon at gmail.com> wrote:
> >
> > On Odroid C1+ and Odroid C2 USB feature is broken
> with "broken" you mean the hotplug and IRQ issues you describe below?
> I think that these are not PHY related but rather a problem with the
> dwc2 IP/driver
>
> > this code changes are just re-structure the code so that
> > proper callback function execute in proper order.
> >
> > Code changes losely based on phy-meson-gxl-usb2.c
> there's a big difference between the Meson8 and GXL drivers:
> GXL requires changing some of the PHY registers at runtime based on
> the mode (host/peripheral).
> The Meson8 PHY however (as far as I can tell from the 3.10 and 3.14
> kernels) don't require any runtime changes based on the mode.
>
Yes I have gone through 3.10 and 3.14 kernel + u-boot source code
My intent is to simplify the code changes so that they will be
flexible to be used
in the future API.  It does not solve the problem.

> > Initially if we connect USB HDD at initial boot it get detected.
> > but after that usb hotplug of USB HDD is broken.
> > I did not observe and USB debug events messages to trace the root cause.
> >
> > Another issue I observed is increase of USB interrupts event
> > even if there is not much activity on USB ports.
> > I tried some clk changes but it did not workout for me.
> I suggest reporting this to the dwc2 maintainers and asking for advice
> on how to debug these issues.
>
Yes I have enabled the CONFIG_USB_DWC2_DEBUG
to help debug this issue but could not find much clue on
why this is happening.

I will keep debugging the DWC2 code or try to understand the missing features.

>
> Best regards,
> Martin

Thanks



-Anand



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