Re: [PATCH v2] usb: dwc2: drd: fix inconsistent mode if role-switch-default-mode="host"

[Amelie Delaunay]

On 3/1/23 12:26, Fabrice Gasnier wrote:
> On 2/22/23 08:00, Minas Harutyunyan wrote:
> > Hi Amelie,
> >
> > Could you please review and test this patch on your setup.
> > Doesn't broke anything.
>
> Hi Minas,
>
> I tested at my end on behalf of Amelie.
> Of course I let her possibly comment.
>
> This doesn't break anything on existing boards. I also tested the
> example described by Ziyang in the commit message.
>
> You can add my:
> Tested-by: Fabrice Gasnier <fabrice.gasnier@xxxxxxxxxxx>

Thanks Fabrice for testing!

You can also add my:
Reviewed-by: Amelie Delaunay <amelie.delaunay@xxxxxxxxxxx>

Regards,
Amelie

> Thanks & BR,
> Fabrice
>
> > Thanks,
> > Minas
> >
> > On 2/21/2023 2:30 PM, Ziyang Huang <hzyitc@xxxxxxxxxxx> wrote:
> > > From: Ziyang Huang <hzyitc@xxxxxxxxxxx>
> > > Sent: Tuesday, February 21, 2023 2:30 PM
> > > To: Minas Harutyunyan <hminas@xxxxxxxxxxxx>
> > > Cc: gregkh@xxxxxxxxxxxxxxxxxxx; fabrice.gasnier@xxxxxxxxxxx;
> > > amelie.delaunay@xxxxxxxxxxx; linux-usb@xxxxxxxxxxxxxxx; linux-
> > > kernel@xxxxxxxxxxxxxxx; Ziyang Huang <hzyitc@xxxxxxxxxxx>
> > > Subject: [PATCH v2] usb: dwc2: drd: fix inconsistent mode if role-switch-
> > > default-mode="host"
> > >
> > > Some boards might use USB-A female connector for USB ports, however, the
> > > port could be connected to a dual-mode USB controller, making it also
> > > behaves as a peripheral device if male-to-male cable is connected.
> > >
> > > In this case, the dts looks like this:
> > >
> > > 	&usb0 {
> > > 		status = "okay";
> > > 		dr_mode = "otg";
> > > 		usb-role-switch;
> > > 		role-switch-default-mode = "host";
> > > 	};
> > >
> > > After boot, dwc2_ovr_init() sets GOTGCTL to GOTGCTL_AVALOVAL and call
> > > dwc2_force_mode() with parameter host=false, which causes inconsistent mode
> > > - The hardware is in peripheral mode while the kernel status is in host
> > > mode.
> > >
> > > What we can do now is to call dwc2_drd_role_sw_set() to switch to device
> > > mode, and everything should work just fine now, even switching back to
> > > none(default) mode afterwards.
> > >
> > > Fixes: e14acb876985 ("usb: dwc2: drd: add role-switch-default-node support")
> > > Signed-off-by: Ziyang Huang <hzyitc@xxxxxxxxxxx>
> > > ---
> > > Changes since v1
> > > - Use corrent name in Signed-off-by
> > >
> > > drivers/usb/dwc2/drd.c | 3 ++-
> > > 1 file changed, 2 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/usb/dwc2/drd.c b/drivers/usb/dwc2/drd.c index
> > > d8d6493bc457..a8605b02115b 100644
> > > --- a/drivers/usb/dwc2/drd.c
> > > +++ b/drivers/usb/dwc2/drd.c
> > > @@ -35,7 +35,8 @@ static void dwc2_ovr_init(struct dwc2_hsotg *hsotg)
> > >
> > > 	spin_unlock_irqrestore(&hsotg->lock, flags);
> > >
> > > -	dwc2_force_mode(hsotg, (hsotg->dr_mode == USB_DR_MODE_HOST));
> > > +	dwc2_force_mode(hsotg, (hsotg->dr_mode == USB_DR_MODE_HOST) ||
> > > +				(hsotg->role_sw_default_mode == USB_DR_MODE_HOST));
> > > }
> > >
> > > static int dwc2_ovr_avalid(struct dwc2_hsotg *hsotg, bool valid)
> > > --
> > > 2.34.1