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

From: Greg KH
Date: Tue Feb 21 2023 - 08:48:56 EST


On Tue, Feb 21, 2023 at 08:33:32PM +0800, Ziyang Huang wrote:
>
> 在 2023/2/21 18:41, Greg KH 写道:
> > On Tue, Feb 21, 2023 at 06:30:04PM +0800, Ziyang Huang wrote:
> > > 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
> > Nope, still incorrect, please use your synopsys address.
> >
> > thanks,
> >
> > greg k-h
>
>
> Oh, I'm not a Synopsys employee but a free developer. This is my first time
> submitting a kernel patch, please excuse me. Thank you.

Ah, my fault, sorry, I saw the synopsys email on the to: line and
thought it was you. Nevermind then, sorry, this will be reviewed once
6.3-rc1 is out.

thanks,

greg k-h