Re: [PATCH 1/1] usb: gadget: call usb_gadget_check_config() to verify UDC capability

[Roger Quadros]

On 29/06/2023 03:54, Frank Li wrote:
> The legacy gadget driver omitted calling usb_gadget_check_config()
> to ensure that the USB device controller (UDC) has adequate resources,
> including sufficient endpoint numbers and types, to support the given
> configuration.
> 
> Previously, usb_add_config() was solely invoked by the legacy gadget
> driver. Adds the necessary usb_gadget_check_config() after the bind()
> operation to fix the issue.

You have only fixed composite.c. Not all gadget drivers use composite.c
so it will be still broken for them.

Please also add default sane configuration in CDNS3 so it works even
if usb_gadget_check_config() is not invoked.

> 
> Fixes: dce49449e04f ("usb: cdns3: allocate TX FIFO size according to composite EP number")
> Reported-by: Ravi Gunasekaran <r-gunasekaran@xxxxxx>
> Signed-off-by: Frank Li <Frank.Li@xxxxxxx>
> ---
>  drivers/usb/gadget/composite.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
> index 1b3489149e5e..dd9b90481b4c 100644
> --- a/drivers/usb/gadget/composite.c
> +++ b/drivers/usb/gadget/composite.c
> @@ -1125,6 +1125,10 @@ int usb_add_config(struct usb_composite_dev *cdev,
>  		goto done;
>  
>  	status = bind(config);
> +
> +	if (status == 0)
> +		status = usb_gadget_check_config(cdev->gadget);
> +
>  	if (status < 0) {
>  		while (!list_empty(&config->functions)) {
>  			struct usb_function		*f;

-- 
cheers,
-roger