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

[Xu Yang]

Hi Luca,

> -----Original Message-----
> 
> 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.

Thanks for your feedback. As you said this issue will disappear with below change, right?

	diff --git a/drivers/usb/phy/phy-mxs-usb.c b/drivers/usb/phy/phy-mxs-usb.c
	index e1a2b2ea098b..ec5ee790455e 100644
	--- a/drivers/usb/phy/phy-mxs-usb.c
	+++ b/drivers/usb/phy/phy-mxs-usb.c
	@@ -178,7 +178,6 @@ static const struct mxs_phy_data imx6sx_phy_data = {
	 };

	 static const struct mxs_phy_data imx6ul_phy_data = {
	-       .flags = MXS_PHY_DISCONNECT_LINE_WITHOUT_VBUS,
	 };

	 static const struct mxs_phy_data imx7ulp_phy_data = {

So I guess something in __mxs_phy_disconnect_line(mxs_phy, true) is causing this behavior.
Could you please help to find which line to comment to make this issue disappear?

Thanks,
Xu Yang

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