* @list: for use by the udc class driver
* @vbus: for udcs who care about vbus status, this value is real vbus status;
* for udcs who do not care about vbus status, this value is always true
+ * @started: the UDC's started state. True if the UDC had started.
*
* This represents the internal data structure which is used by the UDC-class
* to hold information about udc driver and gadget together.
struct device dev;
struct list_head list;
bool vbus;
+ bool started;
};
static struct class *udc_class;
*/
static inline int usb_gadget_udc_start(struct usb_udc *udc)
{
- return udc->gadget->ops->udc_start(udc->gadget, udc->driver);
+ int ret;
+
+ if (udc->started) {
+ dev_err(&udc->dev, "UDC had already started\n");
+ return -EBUSY;
+ }
+
+ ret = udc->gadget->ops->udc_start(udc->gadget, udc->driver);
+ if (!ret)
+ udc->started = true;
+
+ return ret;
}
/**
*/
static inline void usb_gadget_udc_stop(struct usb_udc *udc)
{
+ if (!udc->started) {
+ dev_err(&udc->dev, "UDC had already stopped\n");
+ return;
+ }
+
udc->gadget->ops->udc_stop(udc->gadget);
+ udc->started = false;
}
/**
udc->gadget = gadget;
gadget->udc = udc;
+ udc->started = false;
+
mutex_lock(&udc_lock);
list_add_tail(&udc->list, &udc_list);