Date:   Tue, 21 Feb 2023 14:48:45 +0100
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Ziyang Huang <hzyitc@outlook.com>
Cc:     hminas@synopsys.com, fabrice.gasnier@foss.st.com,
        amelie.delaunay@foss.st.com, linux-usb@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2] usb: dwc2: drd: fix inconsistent mode if
 role-switch-default-mode="host"
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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@outlook.com>
> > > ---
> > > 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