Re: [PATCH v2 2/3] usb: chipidea: imx: support disabling runtime-pm

From: Francesco Dolcini
Date: Fri May 05 2023 - 06:59:01 EST


On Fri, May 05, 2023 at 11:23:51AM +0200, Luca Ceresoli wrote:
> On Thu, 4 May 2023 18:50:14 +0200
> Francesco Dolcini <francesco@xxxxxxxxxx> wrote:
>
> > Hello Luca,
> > I guess your mail to Philippe bounced, let me try to answer since I am aware
> > of the issue here.
> >
> > On Thu, May 04, 2023 at 06:23:12PM +0200, Luca Ceresoli wrote:
> > > I found this thread after several hours spent in debugging why USB host is
> > > not detecting new devices on a custom board using the iMX6ULL Colibri
> > > SoM.
> > >
> > > My best workaround at the moment is:
> > We have the same workaround in our BSP since quite some time, see
> > https://git.toradex.com/cgit/meta-toradex-bsp-common.git/tree/recipes-kernel/linux/linux-toradex-mainline-git/0002-drivers-chipidea-disable-runtime-pm-for-imx6ul.patch
> >
> > > I haven't found any follow-up patches from you, so I'm wondering whether
> > > you have made any progress on this issue.
> > You can find the latest discussion on that regard here
> > https://lore.kernel.org/all/Y1vLpaxpc5WBCuGD@xxxxxxxxxxxxxxxxxxxxxxxxxxxx/
>
> Thanks for this pointer! I have read the discussion and it was a bit
> confusing, especially about whether the hardware can work at all.

It can work. Hardware wise is just fine, software wise I tried to
explain how in my previous answer to you. Worst case we would have to
describe the hardware in a different way in the DTS, but I do not expect
this to be required.

> Are you planning to continue on that work?

Hopefully NXP / Li Jun will be able to help.

Francesco