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* [PATCH] usb: dwc2: drd: fix inconsistent mode if role-switch-default-mode="host"
@ 2023-02-20 18:05 hzy
  2023-02-20 18:58 ` Greg KH
  0 siblings, 1 reply; 2+ messages in thread
From: hzy @ 2023-02-20 18:05 UTC (permalink / raw)
  To: hminas
  Cc: gregkh, fabrice.gasnier, amelie.delaunay, linux-usb, linux-kernel, hzy

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: hzy <hzyitc@outlook.com>
---
 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


^ permalink raw reply related	[flat|nested] 2+ messages in thread

* Re: [PATCH] usb: dwc2: drd: fix inconsistent mode if role-switch-default-mode="host"
  2023-02-20 18:05 [PATCH] usb: dwc2: drd: fix inconsistent mode if role-switch-default-mode="host" hzy
@ 2023-02-20 18:58 ` Greg KH
  0 siblings, 0 replies; 2+ messages in thread
From: Greg KH @ 2023-02-20 18:58 UTC (permalink / raw)
  To: hzy; +Cc: hminas, fabrice.gasnier, amelie.delaunay, linux-usb, linux-kernel

On Tue, Feb 21, 2023 at 02:05:35AM +0800, hzy 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: hzy <hzyitc@outlook.com>

Signed-off-by does not match your "From:" line of your patch :(

Please fix up and use the correct name here as our documentation asks
for.

thanks,

greg k-h

^ permalink raw reply	[flat|nested] 2+ messages in thread

end of thread, other threads:[~2023-02-20 18:59 UTC | newest]

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2023-02-20 18:05 [PATCH] usb: dwc2: drd: fix inconsistent mode if role-switch-default-mode="host" hzy
2023-02-20 18:58 ` Greg KH

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