[deliverable/linux.git] / drivers / usb / otg / otg.c

/*
 * otg.c -- USB OTG utility code
 *
 * Copyright (C) 2004 Texas Instruments
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */

#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/device.h>

#include <linux/usb/otg.h>

static struct usb_phy *phy;

/**
 * usb_get_transceiver - find the (single) USB transceiver
 *
 * Returns the transceiver driver, after getting a refcount to it; or
 * null if there is no such transceiver.  The caller is responsible for
 * calling usb_put_transceiver() to release that count.
 *
 * For use by USB host and peripheral drivers.
 */
struct usb_phy *usb_get_transceiver(void)
{
	if (phy)
		get_device(phy->dev);
	return phy;
}
EXPORT_SYMBOL(usb_get_transceiver);

/**
 * usb_put_transceiver - release the (single) USB transceiver
 * @x: the transceiver returned by usb_get_transceiver()
 *
 * Releases a refcount the caller received from usb_get_transceiver().
 *
 * For use by USB host and peripheral drivers.
 */
void usb_put_transceiver(struct usb_phy *x)
{
	if (x)
		put_device(x->dev);
}
EXPORT_SYMBOL(usb_put_transceiver);

/**
 * usb_set_transceiver - declare the (single) USB transceiver
 * @x: the USB transceiver to be used; or NULL
 *
 * This call is exclusively for use by transceiver drivers, which
 * coordinate the activities of drivers for host and peripheral
 * controllers, and in some cases for VBUS current regulation.
 */
int usb_set_transceiver(struct usb_phy *x)
{
	if (phy && x)
		return -EBUSY;
	phy = x;
	return 0;
}
EXPORT_SYMBOL(usb_set_transceiver);

const char *otg_state_string(enum usb_otg_state state)
{
	switch (state) {
	case OTG_STATE_A_IDLE:
		return "a_idle";
	case OTG_STATE_A_WAIT_VRISE:
		return "a_wait_vrise";
	case OTG_STATE_A_WAIT_BCON:
		return "a_wait_bcon";
	case OTG_STATE_A_HOST:
		return "a_host";
	case OTG_STATE_A_SUSPEND:
		return "a_suspend";
	case OTG_STATE_A_PERIPHERAL:
		return "a_peripheral";
	case OTG_STATE_A_WAIT_VFALL:
		return "a_wait_vfall";
	case OTG_STATE_A_VBUS_ERR:
		return "a_vbus_err";
	case OTG_STATE_B_IDLE:
		return "b_idle";
	case OTG_STATE_B_SRP_INIT:
		return "b_srp_init";
	case OTG_STATE_B_PERIPHERAL:
		return "b_peripheral";
	case OTG_STATE_B_WAIT_ACON:
		return "b_wait_acon";
	case OTG_STATE_B_HOST:
		return "b_host";
	default:
		return "UNDEFINED";
	}
}
EXPORT_SYMBOL(otg_state_string);
Commit	Line	Data
3cb22d65 TL	1	/*
	2	* otg.c -- USB OTG utility code
	3	*
	4	* Copyright (C) 2004 Texas Instruments
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2 of the License, or
	9	* (at your option) any later version.
	10	*/
	11
	12	#include <linux/kernel.h>
f940fcd8	13	#include <linux/export.h>
3cb22d65 TL	14	#include <linux/device.h>
	15
	16	#include <linux/usb/otg.h>
	17
7a8a3a9b	18	static struct usb_phy *phy;
3cb22d65 TL	19
3cb22d65 TL	20	/**
7a8a3a9b	21	* usb_get_transceiver - find the (single) USB transceiver
3cb22d65 TL	22	*
	23	* Returns the transceiver driver, after getting a refcount to it; or
	24	* null if there is no such transceiver. The caller is responsible for
7a8a3a9b	25	* calling usb_put_transceiver() to release that count.
3cb22d65 TL	26	*
	27	* For use by USB host and peripheral drivers.
	28	*/
7a8a3a9b	29	struct usb_phy *usb_get_transceiver(void)
3cb22d65	30	{
7a8a3a9b HK	31	if (phy)
	32	get_device(phy->dev);
	33	return phy;
3cb22d65	34	}
7a8a3a9b	35	EXPORT_SYMBOL(usb_get_transceiver);
3cb22d65 TL	36
3cb22d65 TL	37	/**
7a8a3a9b HK	38	* usb_put_transceiver - release the (single) USB transceiver
7a8a3a9b HK	39	* @x: the transceiver returned by usb_get_transceiver()
3cb22d65	40	*
7a8a3a9b	41	* Releases a refcount the caller received from usb_get_transceiver().
3cb22d65 TL	42	*
	43	* For use by USB host and peripheral drivers.
	44	*/
7a8a3a9b	45	void usb_put_transceiver(struct usb_phy *x)
3cb22d65	46	{
ecf85e48 RJ	47	if (x)
ecf85e48 RJ	48	put_device(x->dev);
3cb22d65	49	}
7a8a3a9b	50	EXPORT_SYMBOL(usb_put_transceiver);
3cb22d65 TL	51
3cb22d65 TL	52	/**
7a8a3a9b HK	53	* usb_set_transceiver - declare the (single) USB transceiver
7a8a3a9b HK	54	* @x: the USB transceiver to be used; or NULL
3cb22d65 TL	55	*
	56	* This call is exclusively for use by transceiver drivers, which
	57	* coordinate the activities of drivers for host and peripheral
	58	* controllers, and in some cases for VBUS current regulation.
	59	*/
7a8a3a9b	60	int usb_set_transceiver(struct usb_phy *x)
3cb22d65	61	{
7a8a3a9b	62	if (phy && x)
3cb22d65	63	return -EBUSY;
7a8a3a9b	64	phy = x;
3cb22d65 TL	65	return 0;
3cb22d65 TL	66	}
7a8a3a9b	67	EXPORT_SYMBOL(usb_set_transceiver);
3dacdf11 AG	68
	69	const char *otg_state_string(enum usb_otg_state state)
	70	{
	71	switch (state) {
	72	case OTG_STATE_A_IDLE:
	73	return "a_idle";
	74	case OTG_STATE_A_WAIT_VRISE:
	75	return "a_wait_vrise";
	76	case OTG_STATE_A_WAIT_BCON:
	77	return "a_wait_bcon";
	78	case OTG_STATE_A_HOST:
	79	return "a_host";
	80	case OTG_STATE_A_SUSPEND:
	81	return "a_suspend";
	82	case OTG_STATE_A_PERIPHERAL:
	83	return "a_peripheral";
	84	case OTG_STATE_A_WAIT_VFALL:
	85	return "a_wait_vfall";
	86	case OTG_STATE_A_VBUS_ERR:
	87	return "a_vbus_err";
	88	case OTG_STATE_B_IDLE:
	89	return "b_idle";
	90	case OTG_STATE_B_SRP_INIT:
	91	return "b_srp_init";
	92	case OTG_STATE_B_PERIPHERAL:
	93	return "b_peripheral";
	94	case OTG_STATE_B_WAIT_ACON:
	95	return "b_wait_acon";
	96	case OTG_STATE_B_HOST:
	97	return "b_host";
	98	default:
	99	return "UNDEFINED";
	100	}
	101	}
	102	EXPORT_SYMBOL(otg_state_string);