Re: [PATCH v2 2/2] usb: gadget: udc: Handle gadget_connect failure during bind operation

[Krishna Kurapati PSSNV <quic_kriskura@quicinc.com>]

Hi Alan, Geert,

  Can you help review and provide comments/approval on the following patch.

Regards,
Krishna,

On 3/28/2023 9:37 PM, Krishna Kurapati wrote:
> In the event, gadget_connect call (which invokes pullup) fails,
> propagate the error to udc bind operation which inturn sends the
> error to configfs. The userspace can then retry enumeartion if
> it chooses to.
> 
> Signed-off-by: Krishna Kurapati <quic_kriskura@quicinc.com>
> ---
>   drivers/usb/gadget/udc/core.c | 20 ++++++++++++++++----
>   1 file changed, 16 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/usb/gadget/udc/core.c b/drivers/usb/gadget/udc/core.c
> index 23b0629a8774..975205a1853f 100644
> --- a/drivers/usb/gadget/udc/core.c
> +++ b/drivers/usb/gadget/udc/core.c
> @@ -1051,12 +1051,16 @@ EXPORT_SYMBOL_GPL(usb_gadget_set_state);
>   
>   /* ------------------------------------------------------------------------- */
>   
> -static void usb_udc_connect_control(struct usb_udc *udc)
> +static int usb_udc_connect_control(struct usb_udc *udc)
>   {
> +	int ret;
> +
>   	if (udc->vbus)
> -		usb_gadget_connect(udc->gadget);
> +		ret = usb_gadget_connect(udc->gadget);
>   	else
> -		usb_gadget_disconnect(udc->gadget);
> +		ret = usb_gadget_disconnect(udc->gadget);
> +
> +	return ret;
>   }
>   
>   /**
> @@ -1500,11 +1504,19 @@ static int gadget_bind_driver(struct device *dev)
>   	if (ret)
>   		goto err_start;
>   	usb_gadget_enable_async_callbacks(udc);
> -	usb_udc_connect_control(udc);
> +	ret = usb_udc_connect_control(udc);
> +	if (ret)
> +		goto err_connect_control;
>   
>   	kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
>   	return 0;
>   
> + err_connect_control:
> +	usb_gadget_disable_async_callbacks(udc);
> +	if (gadget->irq)
> +		synchronize_irq(gadget->irq);
> +	usb_gadget_udc_stop(udc);
> +
>    err_start:
>   	driver->unbind(udc->gadget);
>