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

From: Anand Moon
Date: Mon Jun 21 2021 - 03:21:17 EST


Hi Martin,

On Sat, 19 Jun 2021 at 01:47, Martin Blumenstingl
<martin.blumenstingl@xxxxxxxxxxxxxx> wrote:
>
> Hi Anand,
>
> On Fri, Jun 18, 2021 at 3:20 PM Anand Moon <linux.amoon@xxxxxxxxx> wrote:
> [...]
> > (some email id got messed up while sending these changes.)
> it happened to me before: don't worry, it's something that can be fixed
>
> [...]
> > > > 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 think CONFIG_USB_DWC2_DEBUG is a good starting point.
> For myself I came to the conclusion that the dwc2 IP is too complex to
> understand without additional information
> Some additional information can be found in public datasheets of other
> SoCs which are also using a dwc2 core, see for example RK3128 [0] or
> RT3050 [1]
> That's why my suggestion is to additionally ask the dwc2 maintainers
> (which are not Cc'ed on this mail) for debugging suggestions.
>

Yes, I will investigate with mode debugging and Cc USB maintainers in
the next version for more details.

>
> Best regards,
> Martin
>

Thanks for these inputs.
>
> [0] https://rockchip.fr/RK312X%20TRM/chapter-26-usb-otg-2-0.pdf
> [1] http://static6.arrow.com/aropdfconversion/aa9a14376a75e7c5d6daa9f6aaed8411909d2021/rt3050_5x_v2.0_081408_0902.pdf

Thanks

-Anand