Re: [PATCH] usb: gadget: udc: skip pullup() if already connected

[Alan Stern]

On Tue, Apr 21, 2026 at 04:20:50PM +0800, Xu Yang wrote:
> The device controller may update vbus status via usb_udc_vbus_handler(),
> which tries to connect the gadget even though gadget_bind_driver() has
> already called usb_udc_connect_control_locked(). This causes pullup() to
> be called twice. Avoid this by checking if gadget->connected is true.

This patch is wrong.  To see why, read the comments just below the end 
of the patch and see also usb_gadget_activate().

(Also, is there really anything wrong with calling pullup() twice in a 
row?)

Alan Stern

> Signed-off-by: Xu Yang <xu.yang_2@xxxxxxx>
> ---
>  drivers/usb/gadget/udc/core.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/usb/gadget/udc/core.c b/drivers/usb/gadget/udc/core.c
> index e8861eaad907..be29daa7ad3c 100644
> --- a/drivers/usb/gadget/udc/core.c
> +++ b/drivers/usb/gadget/udc/core.c
> @@ -712,6 +712,9 @@ static int usb_gadget_connect_locked(struct usb_gadget *gadget)
>  		goto out;
>  	}
>  
> +	if (gadget->connected)
> +		goto out;
> +
>  	if (gadget->deactivated || !gadget->udc->allow_connect || !gadget->udc->started) {
>  		/*
>  		 * If the gadget isn't usable (because it is deactivated,
> -- 
> 2.34.1
> 
>