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

[Ziyang Huang]

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.