注册OHCI
使用函数usb_create_hcd创建一个struct usb_hcd,usb_add_hcd将struct hc_driver注册到usb core
struct hc_driver
一个重要的结构体struct hc_driver
static const struct hc_driver ohci_platform_hc_driver = {
...
.reset = ohci_platform_reset,//里面调用了ohci_init
.start = ohci_platform_start,//里面调用了ohci_run
.stop = ohci_stop,
.shutdown = ohci_shutdown,
.urb_enqueue &