@@ -1003,6 +1003,25 @@ int usb_gadget_ep_match_desc(struct usb_gadget *gadget,
}
EXPORT_SYMBOL_GPL(usb_gadget_ep_match_desc);
+/**
+ * usb_gadget_check_config - checks if the UDC can support the binded
+ * configuration
+ * @gadget: controller to check the USB configuration
+ *
+ * Ensure that a UDC is able to support the requested resources by a
+ * configuration, and that there are no resource limitations, such as
+ * internal memory allocated to all requested endpoints.
+ *
+ * Returns zero on success, else a negative errno.
+ */
+int usb_gadget_check_config(struct usb_gadget *gadget)
+{
+ if (gadget->ops->check_config)
+ return gadget->ops->check_config(gadget);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(usb_gadget_check_config);
+
/* ------------------------------------------------------------------------- */
static void usb_gadget_state_work(struct work_struct *work)
@@ -329,6 +329,7 @@ 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);
};
/**
@@ -608,6 +609,7 @@ 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);
#else
static inline int usb_gadget_frame_number(struct usb_gadget *gadget)
{ return 0; }
@@ -631,6 +633,8 @@ static inline int usb_gadget_deactivate(struct usb_gadget *gadget)
{ return 0; }
static inline int usb_gadget_activate(struct usb_gadget *gadget)
{ return 0; }
+static inline int usb_gadget_check_config(struct usb_gadget *gadget)
+{ return 0; }
#endif /* CONFIG_USB_GADGET */
/*-------------------------------------------------------------------------*/
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@codeaurora.org> --- drivers/usb/gadget/udc/core.c | 19 +++++++++++++++++++ include/linux/usb/gadget.h | 4 ++++ 2 files changed, 23 insertions(+)