Re: [PATCH] usb: dwc3: drd: Add support for extcon drd notifier even with usb role switch config enabled

[Thinh Nguyen <Thinh.Nguyen@synopsys.com>]

Hi,

Aswath Govindraju wrote:
> In AM62x SoC, the USB controller supports USB role switching by using the
> extcon drd notifiers. The current implementation does not accommodate this.
> If usb role switching is enabled then drd notifiers are not added. If usb
> role switching is not enabled then the dr_mode is forced to peripheral
> (dwc3_get_dr_mode) and role switching will not be possible(dwc3_set_mode).
> 
> Therefore, rearrange the "if else" logic such that extcon drd notifiers can
> be added even with usb role switching enabled.
> 
> Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
> ---
>  drivers/usb/dwc3/drd.c | 16 +++++++++-------
>  1 file changed, 9 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/usb/dwc3/drd.c b/drivers/usb/dwc3/drd.c
> index b919ea3d87f2..0e86b1d8b50c 100644
> --- a/drivers/usb/dwc3/drd.c
> +++ b/drivers/usb/dwc3/drd.c
> @@ -583,12 +583,7 @@ int dwc3_drd_init(struct dwc3 *dwc)
>  	if (IS_ERR(dwc->edev))
>  		return PTR_ERR(dwc->edev);
>  
> -	if (ROLE_SWITCH &&
> -	    device_property_read_bool(dwc->dev, "usb-role-switch")) {
> -		ret = dwc3_setup_role_switch(dwc);
> -		if (ret < 0)
> -			return ret;
> -	} else if (dwc->edev) {
> +	if (dwc->edev) {
>  		dwc->edev_nb.notifier_call = dwc3_drd_notifier;
>  		ret = extcon_register_notifier(dwc->edev, EXTCON_USB_HOST,
>  					       &dwc->edev_nb);
> @@ -598,7 +593,14 @@ int dwc3_drd_init(struct dwc3 *dwc)
>  		}
>  
>  		dwc3_drd_update(dwc);
> -	} else {
> +	}
> +
> +	if (ROLE_SWITCH &&
> +	    device_property_read_bool(dwc->dev, "usb-role-switch")) {
> +		ret = dwc3_setup_role_switch(dwc);
> +		if (ret < 0)
> +			return ret;
> +	} else if (!dwc->edev) {
>  		dwc3_set_prtcap(dwc, DWC3_GCTL_PRTCAP_OTG);
>  
>  		/* use OTG block to get ID event */


Please check the patch by Andrey Smirnov and see if it works for you:
https://lore.kernel.org/linux-usb/20220221192020.346622-1-andrew.smirnov@gmail.com/

Thanks,
Thinh