USB_REQ_CLEAR_FEATURE  550 include/linux/usb/hcd.h #define ClearHubFeature		(0x2000 | USB_REQ_CLEAR_FEATURE)
USB_REQ_CLEAR_FEATURE  551 include/linux/usb/hcd.h #define ClearPortFeature	(0x2300 | USB_REQ_CLEAR_FEATURE)