root/include/linux/usb/otg.h

INCLUDED FROM

DEFINITIONS

1. otg_start_hnp
2. otg_set_vbus
3. otg_set_host
4. otg_set_peripheral
5. otg_start_srp

/* USB OTG (On The Go) defines */
/*
 *
 * These APIs may be used between USB controllers.  USB device drivers
 * (for either host or peripheral roles) don't use these calls; they
 * continue to use just usb_device and usb_gadget.
 */

#ifndef __LINUX_USB_OTG_H
#define __LINUX_USB_OTG_H

#include <linux/usb/phy.h>

struct usb_otg {
        u8                      default_a;

        struct usb_phy          *phy;
        struct usb_bus          *host;
        struct usb_gadget       *gadget;

        /* bind/unbind the host controller */
        int     (*set_host)(struct usb_otg *otg, struct usb_bus *host);

        /* bind/unbind the peripheral controller */
        int     (*set_peripheral)(struct usb_otg *otg,
                                        struct usb_gadget *gadget);

        /* effective for A-peripheral, ignored for B devices */
        int     (*set_vbus)(struct usb_otg *otg, bool enabled);

        /* for B devices only:  start session with A-Host */
        int     (*start_srp)(struct usb_otg *otg);

        /* start or continue HNP role switch */
        int     (*start_hnp)(struct usb_otg *otg);

};

extern const char *usb_otg_state_string(enum usb_otg_state state);

/* Context: can sleep */
static inline int
otg_start_hnp(struct usb_otg *otg)
{
        if (otg && otg->start_hnp)
                return otg->start_hnp(otg);

        return -ENOTSUPP;
}

/* Context: can sleep */
static inline int
otg_set_vbus(struct usb_otg *otg, bool enabled)
{
        if (otg && otg->set_vbus)
                return otg->set_vbus(otg, enabled);

        return -ENOTSUPP;
}

/* for HCDs */
static inline int
otg_set_host(struct usb_otg *otg, struct usb_bus *host)
{
        if (otg && otg->set_host)
                return otg->set_host(otg, host);

        return -ENOTSUPP;
}

/* for usb peripheral controller drivers */

/* Context: can sleep */
static inline int
otg_set_peripheral(struct usb_otg *otg, struct usb_gadget *periph)
{
        if (otg && otg->set_peripheral)
                return otg->set_peripheral(otg, periph);

        return -ENOTSUPP;
}

static inline int
otg_start_srp(struct usb_otg *otg)
{
        if (otg && otg->start_srp)
                return otg->start_srp(otg);

        return -ENOTSUPP;
}

/* for OTG controller drivers (and maybe other stuff) */
extern int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num);

enum usb_dr_mode {
        USB_DR_MODE_UNKNOWN,
        USB_DR_MODE_HOST,
        USB_DR_MODE_PERIPHERAL,
        USB_DR_MODE_OTG,
};

#endif /* __LINUX_USB_OTG_H */