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

From: Luca Ceresoli
Date: Tue Jul 18 2023 - 08:25:16 EST


Hello Xu,

On Tue, 18 Jul 2023 08:31:48 +0000
Xu Yang <xu.yang_2@xxxxxxx> wrote:

> > -----Original Message-----
> >
> > Ciao Francesco,
> >
> > On Thu, 6 Jul 2023 12:23:43 +0200
> > Francesco Dolcini <francesco@xxxxxxxxxx> wrote:
> >
> > > Hello Luca,
> > >
> > > On Tue, May 30, 2023 at 11:22:51AM +0000, Jun Li wrote:
> > > > Yes, your understanding is correct, talked with Xu(in CC), he will take this
> > > > soon.
> > >
> > > A series was posted
> > >
> > > I had no time to try or look at it yet.
> >
> > Thanks for keeping me up to date on this topic, which is still totally
> > relevant to me.
> >
> > I looked at the series, but it does not seem to be addressing the
> > problem with USB host not detecting new devices when VBUS is not
> > directly connected, e.g. in the Colibri imx6ull SoM.
> >
> > Xu, do you confirm the series at the link is _not_ solving the problem
> > being discussed here?
>
> Have you tried this patchset? The upstream driver couldn't get correct
> USB role from HW_USBPHY_CTRL register when the ID pin is float. This is
> what this patchset is trying to fix. With this patch, condition
> "(!vbus_is_on && !mxs_phy_is_otg_host(mxs_phy)" will always be false when
> controller acts as host role, then __mxs_phy_disconnect_line(phy, true)
> will never be called. So I think it doesn't matter whether VBUS is connected
> or not when act as host mode. If you still have issue after apply this patchset,
> please let me know.

I tested this patchset on top of v6.5-rc2 and I confirm USB detection
is still broken on the Colibri iMX6ULL. With or without the patches
the behavior is the same: USB devices are detected only during boot,
and anything connected after boot are never detected.

For the archives, I'm replying also to the patch series.

Luca

--
Luca Ceresoli, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com