linux_kernel/drivers/usb/core/phy.h

struct device;
struct usb_phy_roothub;

struct usb_phy_roothub *usb_phy_roothub_alloc(struct device *dev);

int usb_phy_roothub_init(struct usb_phy_roothub *phy_roothub);
int usb_phy_roothub_exit(struct usb_phy_roothub *phy_roothub);

int usb_phy_roothub_power_on(struct usb_phy_roothub *phy_roothub);
void usb_phy_roothub_power_off(struct usb_phy_roothub *phy_roothub);

int usb_phy_roothub_suspend(struct device *controller_dev,
			    struct usb_phy_roothub *phy_roothub);
int usb_phy_roothub_resume(struct device *controller_dev,
			   struct usb_phy_roothub *phy_roothub);