Re: [PATCH v6 1/4] usb: gadget: udc: core: Introduce check_config to verify USB configuration

[Alan Stern]

On Thu, Jan 21, 2021 at 08:01:37PM -0800, Wesley Cheng wrote:
> Some UDCs may have constraints on how many high bandwidth endpoints it can
> support in a certain configuration.  This API allows for the composite
> driver to pass down the total number of endpoints to the UDC so it can verify
> it has the required resources to support the configuration.
> 
> Signed-off-by: Wesley Cheng <wcheng@xxxxxxxxxxxxxx>


> --- a/include/linux/usb/gadget.h
> +++ b/include/linux/usb/gadget.h
> @@ -328,6 +328,7 @@ struct usb_gadget_ops {
>  	struct usb_ep *(*match_ep)(struct usb_gadget *,
>  			struct usb_endpoint_descriptor *,
>  			struct usb_ss_ep_comp_descriptor *);
> +	int	(*check_config)(struct usb_gadget *gadget, unsigned long ep_map);
>  };
>  
>  /**
> @@ -607,6 +608,7 @@ int usb_gadget_connect(struct usb_gadget *gadget);
>  int usb_gadget_disconnect(struct usb_gadget *gadget);
>  int usb_gadget_deactivate(struct usb_gadget *gadget);
>  int usb_gadget_activate(struct usb_gadget *gadget);
> +int usb_gadget_check_config(struct usb_gadget *gadget, unsigned long ep_map);
>  #else
>  static inline int usb_gadget_frame_number(struct usb_gadget *gadget)
>  { return 0; }

Don't you also need an entry for the case where CONFIG_USB_GADGET isn't 
enabled?

Alan Stern