[deliverable/linux.git] / drivers / net / phy / mdio_bus.c

/*
 * drivers/net/phy/mdio_bus.c
 *
 * MDIO Bus interface
 *
 * Author: Andy Fleming
 *
 * Copyright (c) 2004 Freescale Semiconductor, Inc.
 *
 * 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.
 *
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/unistd.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/of_device.h>
#include <linux/of_mdio.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/skbuff.h>
#include <linux/spinlock.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/mii.h>
#include <linux/ethtool.h>
#include <linux/phy.h>

#include <asm/io.h>
#include <asm/irq.h>
#include <asm/uaccess.h>

/**
 * mdiobus_alloc_size - allocate a mii_bus structure
 * @size: extra amount of memory to allocate for private storage.
 * If non-zero, then bus->priv is points to that memory.
 *
 * Description: called by a bus driver to allocate an mii_bus
 * structure to fill in.
 */
struct mii_bus *mdiobus_alloc_size(size_t size)
{
	struct mii_bus *bus;
	size_t aligned_size = ALIGN(sizeof(*bus), NETDEV_ALIGN);
	size_t alloc_size;

	/* If we alloc extra space, it should be aligned */
	if (size)
		alloc_size = aligned_size + size;
	else
		alloc_size = sizeof(*bus);

	bus = kzalloc(alloc_size, GFP_KERNEL);
	if (bus) {
		bus->state = MDIOBUS_ALLOCATED;
		if (size)
			bus->priv = (void *)bus + aligned_size;
	}

	return bus;
}
EXPORT_SYMBOL(mdiobus_alloc_size);

/**
 * mdiobus_release - mii_bus device release callback
 * @d: the target struct device that contains the mii_bus
 *
 * Description: called when the last reference to an mii_bus is
 * dropped, to free the underlying memory.
 */
static void mdiobus_release(struct device *d)
{
	struct mii_bus *bus = to_mii_bus(d);
	BUG_ON(bus->state != MDIOBUS_RELEASED &&
	       /* for compatibility with error handling in drivers */
	       bus->state != MDIOBUS_ALLOCATED);
	kfree(bus);
}

static struct class mdio_bus_class = {
	.name		= "mdio_bus",
	.dev_release	= mdiobus_release,
};

#if IS_ENABLED(CONFIG_OF_MDIO)
/* Helper function for of_mdio_find_bus */
static int of_mdio_bus_match(struct device *dev, const void *mdio_bus_np)
{
	return dev->of_node == mdio_bus_np;
}
/**
 * of_mdio_find_bus - Given an mii_bus node, find the mii_bus.
 * @mdio_bus_np: Pointer to the mii_bus.
 *
 * Returns a pointer to the mii_bus, or NULL if none found.
 *
 * Because the association of a device_node and mii_bus is made via
 * of_mdiobus_register(), the mii_bus cannot be found before it is
 * registered with of_mdiobus_register().
 *
 */
struct mii_bus *of_mdio_find_bus(struct device_node *mdio_bus_np)
{
	struct device *d;

	if (!mdio_bus_np)
		return NULL;

	d = class_find_device(&mdio_bus_class, NULL,  mdio_bus_np,
			      of_mdio_bus_match);

	return d ? to_mii_bus(d) : NULL;
}
EXPORT_SYMBOL(of_mdio_find_bus);
#endif

/**
 * mdiobus_register - bring up all the PHYs on a given bus and attach them to bus
 * @bus: target mii_bus
 *
 * Description: Called by a bus driver to bring up all the PHYs
 *   on a given bus, and attach them to the bus.
 *
 * Returns 0 on success or < 0 on error.
 */
int mdiobus_register(struct mii_bus *bus)
{
	int i, err;

	if (NULL == bus || NULL == bus->name ||
			NULL == bus->read ||
			NULL == bus->write)
		return -EINVAL;

	BUG_ON(bus->state != MDIOBUS_ALLOCATED &&
	       bus->state != MDIOBUS_UNREGISTERED);

	bus->dev.parent = bus->parent;
	bus->dev.class = &mdio_bus_class;
	bus->dev.groups = NULL;
	dev_set_name(&bus->dev, "%s", bus->id);

	err = device_register(&bus->dev);
	if (err) {
		pr_err("mii_bus %s failed to register\n", bus->id);
		return -EINVAL;
	}

	mutex_init(&bus->mdio_lock);

	if (bus->reset)
		bus->reset(bus);

	for (i = 0; i < PHY_MAX_ADDR; i++) {
		if ((bus->phy_mask & (1 << i)) == 0) {
			struct phy_device *phydev;

			phydev = mdiobus_scan(bus, i);
			if (IS_ERR(phydev)) {
				err = PTR_ERR(phydev);
				goto error;
			}
		}
	}

	bus->state = MDIOBUS_REGISTERED;
	pr_info("%s: probed\n", bus->name);
	return 0;

error:
	while (--i >= 0) {
		if (bus->phy_map[i])
			device_unregister(&bus->phy_map[i]->dev);
	}
	device_del(&bus->dev);
	return err;
}
EXPORT_SYMBOL(mdiobus_register);

void mdiobus_unregister(struct mii_bus *bus)
{
	int i;

	BUG_ON(bus->state != MDIOBUS_REGISTERED);
	bus->state = MDIOBUS_UNREGISTERED;

	device_del(&bus->dev);
	for (i = 0; i < PHY_MAX_ADDR; i++) {
		if (bus->phy_map[i])
			device_unregister(&bus->phy_map[i]->dev);
		bus->phy_map[i] = NULL;
	}
}
EXPORT_SYMBOL(mdiobus_unregister);

/**
 * mdiobus_free - free a struct mii_bus
 * @bus: mii_bus to free
 *
 * This function releases the reference to the underlying device
 * object in the mii_bus.  If this is the last reference, the mii_bus
 * will be freed.
 */
void mdiobus_free(struct mii_bus *bus)
{
	/*
	 * For compatibility with error handling in drivers.
	 */
	if (bus->state == MDIOBUS_ALLOCATED) {
		kfree(bus);
		return;
	}

	BUG_ON(bus->state != MDIOBUS_UNREGISTERED);
	bus->state = MDIOBUS_RELEASED;

	put_device(&bus->dev);
}
EXPORT_SYMBOL(mdiobus_free);

struct phy_device *mdiobus_scan(struct mii_bus *bus, int addr)
{
	struct phy_device *phydev;
	int err;

	phydev = get_phy_device(bus, addr, false);
	if (IS_ERR(phydev) || phydev == NULL)
		return phydev;

	err = phy_device_register(phydev);
	if (err) {
		phy_device_free(phydev);
		return NULL;
	}

	return phydev;
}
EXPORT_SYMBOL(mdiobus_scan);

/**
 * mdiobus_read - Convenience function for reading a given MII mgmt register
 * @bus: the mii_bus struct
 * @addr: the phy address
 * @regnum: register number to read
 *
 * NOTE: MUST NOT be called from interrupt context,
 * because the bus read/write functions may wait for an interrupt
 * to conclude the operation.
 */
int mdiobus_read(struct mii_bus *bus, int addr, u32 regnum)
{
	int retval;

	BUG_ON(in_interrupt());

	mutex_lock(&bus->mdio_lock);
	retval = bus->read(bus, addr, regnum);
	mutex_unlock(&bus->mdio_lock);

	return retval;
}
EXPORT_SYMBOL(mdiobus_read);

/**
 * mdiobus_write - Convenience function for writing a given MII mgmt register
 * @bus: the mii_bus struct
 * @addr: the phy address
 * @regnum: register number to write
 * @val: value to write to @regnum
 *
 * NOTE: MUST NOT be called from interrupt context,
 * because the bus read/write functions may wait for an interrupt
 * to conclude the operation.
 */
int mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val)
{
	int err;

	BUG_ON(in_interrupt());

	mutex_lock(&bus->mdio_lock);
	err = bus->write(bus, addr, regnum, val);
	mutex_unlock(&bus->mdio_lock);

	return err;
}
EXPORT_SYMBOL(mdiobus_write);

/**
 * mdio_bus_match - determine if given PHY driver supports the given PHY device
 * @dev: target PHY device
 * @drv: given PHY driver
 *
 * Description: Given a PHY device, and a PHY driver, return 1 if
 *   the driver supports the device.  Otherwise, return 0.
 */
static int mdio_bus_match(struct device *dev, struct device_driver *drv)
{
	struct phy_device *phydev = to_phy_device(dev);
	struct phy_driver *phydrv = to_phy_driver(drv);

	if (of_driver_match_device(dev, drv))
		return 1;

	if (phydrv->match_phy_device)
		return phydrv->match_phy_device(phydev);

	return ((phydrv->phy_id & phydrv->phy_id_mask) ==
		(phydev->phy_id & phydrv->phy_id_mask));
}

#ifdef CONFIG_PM

static bool mdio_bus_phy_may_suspend(struct phy_device *phydev)
{
	struct device_driver *drv = phydev->dev.driver;
	struct phy_driver *phydrv = to_phy_driver(drv);
	struct net_device *netdev = phydev->attached_dev;

	if (!drv || !phydrv->suspend)
		return false;

	/* PHY not attached? May suspend. */
	if (!netdev)
		return true;

	/*
	 * Don't suspend PHY if the attched netdev parent may wakeup.
	 * The parent may point to a PCI device, as in tg3 driver.
	 */
	if (netdev->dev.parent && device_may_wakeup(netdev->dev.parent))
		return false;

	/*
	 * Also don't suspend PHY if the netdev itself may wakeup. This
	 * is the case for devices w/o underlaying pwr. mgmt. aware bus,
	 * e.g. SoC devices.
	 */
	if (device_may_wakeup(&netdev->dev))
		return false;

	return true;
}

static int mdio_bus_suspend(struct device *dev)
{
	struct phy_driver *phydrv = to_phy_driver(dev->driver);
	struct phy_device *phydev = to_phy_device(dev);

	/*
	 * We must stop the state machine manually, otherwise it stops out of
	 * control, possibly with the phydev->lock held. Upon resume, netdev
	 * may call phy routines that try to grab the same lock, and that may
	 * lead to a deadlock.
	 */
	if (phydev->attached_dev && phydev->adjust_link)
		phy_stop_machine(phydev);

	if (!mdio_bus_phy_may_suspend(phydev))
		return 0;

	return phydrv->suspend(phydev);
}

static int mdio_bus_resume(struct device *dev)
{
	struct phy_driver *phydrv = to_phy_driver(dev->driver);
	struct phy_device *phydev = to_phy_device(dev);
	int ret;

	if (!mdio_bus_phy_may_suspend(phydev))
		goto no_resume;

	ret = phydrv->resume(phydev);
	if (ret < 0)
		return ret;

no_resume:
	if (phydev->attached_dev && phydev->adjust_link)
		phy_start_machine(phydev, NULL);

	return 0;
}

static int mdio_bus_restore(struct device *dev)
{
	struct phy_device *phydev = to_phy_device(dev);
	struct net_device *netdev = phydev->attached_dev;
	int ret;

	if (!netdev)
		return 0;

	ret = phy_init_hw(phydev);
	if (ret < 0)
		return ret;

	/* The PHY needs to renegotiate. */
	phydev->link = 0;
	phydev->state = PHY_UP;

	phy_start_machine(phydev, NULL);

	return 0;
}

static struct dev_pm_ops mdio_bus_pm_ops = {
	.suspend = mdio_bus_suspend,
	.resume = mdio_bus_resume,
	.freeze = mdio_bus_suspend,
	.thaw = mdio_bus_resume,
	.restore = mdio_bus_restore,
};

#define MDIO_BUS_PM_OPS (&mdio_bus_pm_ops)

#else

#define MDIO_BUS_PM_OPS NULL

#endif /* CONFIG_PM */

static ssize_t
phy_id_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct phy_device *phydev = to_phy_device(dev);

	return sprintf(buf, "0x%.8lx\n", (unsigned long)phydev->phy_id);
}

static struct device_attribute mdio_dev_attrs[] = {
	__ATTR_RO(phy_id),
	__ATTR_NULL
};

struct bus_type mdio_bus_type = {
	.name		= "mdio_bus",
	.match		= mdio_bus_match,
	.pm		= MDIO_BUS_PM_OPS,
	.dev_attrs	= mdio_dev_attrs,
};
EXPORT_SYMBOL(mdio_bus_type);

int __init mdio_bus_init(void)
{
	int ret;

	ret = class_register(&mdio_bus_class);
	if (!ret) {
		ret = bus_register(&mdio_bus_type);
		if (ret)
			class_unregister(&mdio_bus_class);
	}

	return ret;
}

void mdio_bus_exit(void)
{
	class_unregister(&mdio_bus_class);
	bus_unregister(&mdio_bus_type);
}
Commit	Line	Data
00db8189 AF	1	/*
	2	* drivers/net/phy/mdio_bus.c
	3	*
	4	* MDIO Bus interface
	5	*
	6	* Author: Andy Fleming
	7	*
	8	* Copyright (c) 2004 Freescale Semiconductor, Inc.
	9	*
	10	* This program is free software; you can redistribute it and/or modify it
	11	* under the terms of the GNU General Public License as published by the
	12	* Free Software Foundation; either version 2 of the License, or (at your
	13	* option) any later version.
	14	*
	15	*/
8d242488 JP	16
	17	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
	18
00db8189	19	#include <linux/kernel.h>
00db8189 AF	20	#include <linux/string.h>
	21	#include <linux/errno.h>
	22	#include <linux/unistd.h>
	23	#include <linux/slab.h>
	24	#include <linux/interrupt.h>
	25	#include <linux/init.h>
	26	#include <linux/delay.h>
3d1e4db2	27	#include <linux/device.h>
a30e2c18	28	#include <linux/of_device.h>
4085a7f0	29	#include <linux/of_mdio.h>
00db8189 AF	30	#include <linux/netdevice.h>
	31	#include <linux/etherdevice.h>
	32	#include <linux/skbuff.h>
	33	#include <linux/spinlock.h>
	34	#include <linux/mm.h>
	35	#include <linux/module.h>
00db8189 AF	36	#include <linux/mii.h>
	37	#include <linux/ethtool.h>
	38	#include <linux/phy.h>
	39
	40	#include <asm/io.h>
	41	#include <asm/irq.h>
	42	#include <asm/uaccess.h>
	43
298cf9be	44	/**
eb8a54a7	45	* mdiobus_alloc_size - allocate a mii_bus structure
af58f1d6 RD	46	* @size: extra amount of memory to allocate for private storage.
af58f1d6 RD	47	* If non-zero, then bus->priv is points to that memory.
298cf9be LB	48	*
	49	* Description: called by a bus driver to allocate an mii_bus
	50	* structure to fill in.
	51	*/
eb8a54a7	52	struct mii_bus *mdiobus_alloc_size(size_t size)
298cf9be	53	{
46abc021	54	struct mii_bus *bus;
eb8a54a7 TT	55	size_t aligned_size = ALIGN(sizeof(*bus), NETDEV_ALIGN);
	56	size_t alloc_size;
	57
	58	/* If we alloc extra space, it should be aligned */
	59	if (size)
	60	alloc_size = aligned_size + size;
	61	else
	62	alloc_size = sizeof(*bus);
46abc021	63
eb8a54a7 TT	64	bus = kzalloc(alloc_size, GFP_KERNEL);
eb8a54a7 TT	65	if (bus) {
46abc021	66	bus->state = MDIOBUS_ALLOCATED;
eb8a54a7 TT	67	if (size)
	68	bus->priv = (void *)bus + aligned_size;
	69	}
46abc021 LB	70
46abc021 LB	71	return bus;
298cf9be	72	}
eb8a54a7	73	EXPORT_SYMBOL(mdiobus_alloc_size);
298cf9be	74
46abc021 LB	75	/**
46abc021 LB	76	* mdiobus_release - mii_bus device release callback
78c36b15	77	* @d: the target struct device that contains the mii_bus
46abc021 LB	78	*
	79	* Description: called when the last reference to an mii_bus is
	80	* dropped, to free the underlying memory.
	81	*/
	82	static void mdiobus_release(struct device *d)
	83	{
	84	struct mii_bus *bus = to_mii_bus(d);
161c8d2f KH	85	BUG_ON(bus->state != MDIOBUS_RELEASED &&
	86	/* for compatibility with error handling in drivers */
	87	bus->state != MDIOBUS_ALLOCATED);
46abc021 LB	88	kfree(bus);
	89	}
	90
	91	static struct class mdio_bus_class = {
	92	.name = "mdio_bus",
	93	.dev_release = mdiobus_release,
	94	};
	95
b943fbb0	96	#if IS_ENABLED(CONFIG_OF_MDIO)
25106022	97	/* Helper function for of_mdio_find_bus */
9f3b795a	98	static int of_mdio_bus_match(struct device dev, const void mdio_bus_np)
25106022 DD	99	{
	100	return dev->of_node == mdio_bus_np;
	101	}
	102	/**
	103	* of_mdio_find_bus - Given an mii_bus node, find the mii_bus.
f41ef2e7	104	* @mdio_bus_np: Pointer to the mii_bus.
25106022 DD	105	*
	106	* Returns a pointer to the mii_bus, or NULL if none found.
	107	*
	108	* Because the association of a device_node and mii_bus is made via
	109	* of_mdiobus_register(), the mii_bus cannot be found before it is
	110	* registered with of_mdiobus_register().
	111	*
	112	*/
	113	struct mii_bus of_mdio_find_bus(struct device_node mdio_bus_np)
	114	{
	115	struct device *d;
	116
	117	if (!mdio_bus_np)
	118	return NULL;
	119
	120	d = class_find_device(&mdio_bus_class, NULL, mdio_bus_np,
	121	of_mdio_bus_match);
	122
	123	return d ? to_mii_bus(d) : NULL;
	124	}
	125	EXPORT_SYMBOL(of_mdio_find_bus);
	126	#endif
	127
b3df0da8 RD	128	/**
	129	* mdiobus_register - bring up all the PHYs on a given bus and attach them to bus
	130	* @bus: target mii_bus
e1393456	131	*
b3df0da8 RD	132	* Description: Called by a bus driver to bring up all the PHYs
	133	* on a given bus, and attach them to the bus.
	134	*
	135	* Returns 0 on success or < 0 on error.
e1393456 AF	136	*/
	137	int mdiobus_register(struct mii_bus *bus)
	138	{
161c8d2f	139	int i, err;
e1393456	140
e1393456 AF	141	if (NULL == bus \|\| NULL == bus->name \|\|
	142	NULL == bus->read \|\|
	143	NULL == bus->write)
	144	return -EINVAL;
	145
46abc021 LB	146	BUG_ON(bus->state != MDIOBUS_ALLOCATED &&
	147	bus->state != MDIOBUS_UNREGISTERED);
	148
	149	bus->dev.parent = bus->parent;
	150	bus->dev.class = &mdio_bus_class;
	151	bus->dev.groups = NULL;
036b6687	152	dev_set_name(&bus->dev, "%s", bus->id);
46abc021 LB	153
	154	err = device_register(&bus->dev);
	155	if (err) {
8d242488	156	pr_err("mii_bus %s failed to register\n", bus->id);
46abc021 LB	157	return -EINVAL;
	158	}
	159
d1e7fe4d AB	160	mutex_init(&bus->mdio_lock);
d1e7fe4d AB	161
e1393456 AF	162	if (bus->reset)
	163	bus->reset(bus);
	164
	165	for (i = 0; i < PHY_MAX_ADDR; i++) {
4fd5f812 LB	166	if ((bus->phy_mask & (1 << i)) == 0) {
4fd5f812 LB	167	struct phy_device *phydev;
e1393456	168
4fd5f812	169	phydev = mdiobus_scan(bus, i);
161c8d2f	170	if (IS_ERR(phydev)) {
4fd5f812	171	err = PTR_ERR(phydev);
161c8d2f KH	172	goto error;
161c8d2f KH	173	}
64b1c2b4	174	}
e1393456 AF	175	}
e1393456 AF	176
161c8d2f	177	bus->state = MDIOBUS_REGISTERED;
e1393456	178	pr_info("%s: probed\n", bus->name);
161c8d2f	179	return 0;
e1393456	180
161c8d2f KH	181	error:
	182	while (--i >= 0) {
	183	if (bus->phy_map[i])
	184	device_unregister(&bus->phy_map[i]->dev);
	185	}
	186	device_del(&bus->dev);
e1393456 AF	187	return err;
	188	}
	189	EXPORT_SYMBOL(mdiobus_register);
	190
	191	void mdiobus_unregister(struct mii_bus *bus)
	192	{
	193	int i;
	194
46abc021 LB	195	BUG_ON(bus->state != MDIOBUS_REGISTERED);
	196	bus->state = MDIOBUS_UNREGISTERED;
	197
3e44017b	198	device_del(&bus->dev);
e1393456	199	for (i = 0; i < PHY_MAX_ADDR; i++) {
6f4a7f41	200	if (bus->phy_map[i])
e1393456	201	device_unregister(&bus->phy_map[i]->dev);
4dea547f	202	bus->phy_map[i] = NULL;
e1393456 AF	203	}
	204	}
	205	EXPORT_SYMBOL(mdiobus_unregister);
	206
298cf9be LB	207	/**
	208	* mdiobus_free - free a struct mii_bus
	209	* @bus: mii_bus to free
	210	*
46abc021 LB	211	* This function releases the reference to the underlying device
	212	* object in the mii_bus. If this is the last reference, the mii_bus
	213	* will be freed.
298cf9be LB	214	*/
	215	void mdiobus_free(struct mii_bus *bus)
	216	{
46abc021 LB	217	/*
	218	* For compatibility with error handling in drivers.
	219	*/
	220	if (bus->state == MDIOBUS_ALLOCATED) {
	221	kfree(bus);
	222	return;
	223	}
	224
	225	BUG_ON(bus->state != MDIOBUS_UNREGISTERED);
	226	bus->state = MDIOBUS_RELEASED;
	227
	228	put_device(&bus->dev);
298cf9be LB	229	}
	230	EXPORT_SYMBOL(mdiobus_free);
	231
4fd5f812 LB	232	struct phy_device mdiobus_scan(struct mii_bus bus, int addr)
	233	{
	234	struct phy_device *phydev;
	235	int err;
	236
ac28b9f8	237	phydev = get_phy_device(bus, addr, false);
4fd5f812 LB	238	if (IS_ERR(phydev) \|\| phydev == NULL)
	239	return phydev;
	240
4dea547f	241	err = phy_device_register(phydev);
4fd5f812	242	if (err) {
4fd5f812	243	phy_device_free(phydev);
4dea547f	244	return NULL;
4fd5f812 LB	245	}
4fd5f812 LB	246
4fd5f812 LB	247	return phydev;
	248	}
	249	EXPORT_SYMBOL(mdiobus_scan);
	250
2e888103 LB	251	/**
	252	* mdiobus_read - Convenience function for reading a given MII mgmt register
	253	* @bus: the mii_bus struct
	254	* @addr: the phy address
	255	* @regnum: register number to read
	256	*
	257	* NOTE: MUST NOT be called from interrupt context,
	258	* because the bus read/write functions may wait for an interrupt
	259	* to conclude the operation.
	260	*/
abf35df2	261	int mdiobus_read(struct mii_bus *bus, int addr, u32 regnum)
2e888103 LB	262	{
	263	int retval;
	264
	265	BUG_ON(in_interrupt());
	266
	267	mutex_lock(&bus->mdio_lock);
	268	retval = bus->read(bus, addr, regnum);
	269	mutex_unlock(&bus->mdio_lock);
	270
	271	return retval;
	272	}
	273	EXPORT_SYMBOL(mdiobus_read);
	274
	275	/**
	276	* mdiobus_write - Convenience function for writing a given MII mgmt register
	277	* @bus: the mii_bus struct
	278	* @addr: the phy address
	279	* @regnum: register number to write
	280	* @val: value to write to @regnum
	281	*
	282	* NOTE: MUST NOT be called from interrupt context,
	283	* because the bus read/write functions may wait for an interrupt
	284	* to conclude the operation.
	285	*/
abf35df2	286	int mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val)
2e888103 LB	287	{
	288	int err;
	289
	290	BUG_ON(in_interrupt());
	291
	292	mutex_lock(&bus->mdio_lock);
	293	err = bus->write(bus, addr, regnum, val);
	294	mutex_unlock(&bus->mdio_lock);
	295
	296	return err;
	297	}
	298	EXPORT_SYMBOL(mdiobus_write);
	299
b3df0da8 RD	300	/**
	301	* mdio_bus_match - determine if given PHY driver supports the given PHY device
	302	* @dev: target PHY device
	303	* @drv: given PHY driver
00db8189	304	*
b3df0da8 RD	305	* Description: Given a PHY device, and a PHY driver, return 1 if
b3df0da8 RD	306	* the driver supports the device. Otherwise, return 0.
00db8189 AF	307	*/
	308	static int mdio_bus_match(struct device dev, struct device_driver drv)
	309	{
	310	struct phy_device *phydev = to_phy_device(dev);
	311	struct phy_driver *phydrv = to_phy_driver(drv);
	312
a30e2c18 DD	313	if (of_driver_match_device(dev, drv))
	314	return 1;
	315
	316	if (phydrv->match_phy_device)
	317	return phydrv->match_phy_device(phydev);
	318
5f708dd9 KG	319	return ((phydrv->phy_id & phydrv->phy_id_mask) ==
5f708dd9 KG	320	(phydev->phy_id & phydrv->phy_id_mask));
00db8189 AF	321	}
00db8189 AF	322
2f5cb434 AV	323	#ifdef CONFIG_PM
2f5cb434 AV	324
3d1e4db2 AV	325	static bool mdio_bus_phy_may_suspend(struct phy_device *phydev)
	326	{
	327	struct device_driver *drv = phydev->dev.driver;
	328	struct phy_driver *phydrv = to_phy_driver(drv);
	329	struct net_device *netdev = phydev->attached_dev;
	330
	331	if (!drv \|\| !phydrv->suspend)
	332	return false;
	333
	334	/* PHY not attached? May suspend. */
	335	if (!netdev)
	336	return true;
	337
	338	/*
	339	* Don't suspend PHY if the attched netdev parent may wakeup.
	340	* The parent may point to a PCI device, as in tg3 driver.
	341	*/
	342	if (netdev->dev.parent && device_may_wakeup(netdev->dev.parent))
	343	return false;
	344
	345	/*
	346	* Also don't suspend PHY if the netdev itself may wakeup. This
	347	* is the case for devices w/o underlaying pwr. mgmt. aware bus,
	348	* e.g. SoC devices.
	349	*/
	350	if (device_may_wakeup(&netdev->dev))
	351	return false;
	352
	353	return true;
	354	}
	355
2f5cb434	356	static int mdio_bus_suspend(struct device *dev)
00db8189	357	{
3d1e4db2	358	struct phy_driver *phydrv = to_phy_driver(dev->driver);
0f0ca340	359	struct phy_device *phydev = to_phy_device(dev);
00db8189	360
541cd3ee AV	361	/*
	362	* We must stop the state machine manually, otherwise it stops out of
	363	* control, possibly with the phydev->lock held. Upon resume, netdev
	364	* may call phy routines that try to grab the same lock, and that may
	365	* lead to a deadlock.
	366	*/
fddd9101	367	if (phydev->attached_dev && phydev->adjust_link)
541cd3ee AV	368	phy_stop_machine(phydev);
541cd3ee AV	369
3d1e4db2 AV	370	if (!mdio_bus_phy_may_suspend(phydev))
3d1e4db2 AV	371	return 0;
541cd3ee	372
3d1e4db2	373	return phydrv->suspend(phydev);
00db8189 AF	374	}
00db8189 AF	375
2f5cb434	376	static int mdio_bus_resume(struct device *dev)
00db8189	377	{
3d1e4db2	378	struct phy_driver *phydrv = to_phy_driver(dev->driver);
0f0ca340	379	struct phy_device *phydev = to_phy_device(dev);
541cd3ee	380	int ret;
00db8189	381
3d1e4db2	382	if (!mdio_bus_phy_may_suspend(phydev))
541cd3ee AV	383	goto no_resume;
	384
	385	ret = phydrv->resume(phydev);
	386	if (ret < 0)
	387	return ret;
	388
	389	no_resume:
fddd9101	390	if (phydev->attached_dev && phydev->adjust_link)
541cd3ee AV	391	phy_start_machine(phydev, NULL);
	392
	393	return 0;
00db8189 AF	394	}
00db8189 AF	395
2f5cb434 AV	396	static int mdio_bus_restore(struct device *dev)
	397	{
	398	struct phy_device *phydev = to_phy_device(dev);
	399	struct net_device *netdev = phydev->attached_dev;
	400	int ret;
	401
	402	if (!netdev)
	403	return 0;
	404
	405	ret = phy_init_hw(phydev);
	406	if (ret < 0)
	407	return ret;
	408
	409	/* The PHY needs to renegotiate. */
	410	phydev->link = 0;
	411	phydev->state = PHY_UP;
	412
	413	phy_start_machine(phydev, NULL);
	414
	415	return 0;
	416	}
	417
	418	static struct dev_pm_ops mdio_bus_pm_ops = {
	419	.suspend = mdio_bus_suspend,
	420	.resume = mdio_bus_resume,
	421	.freeze = mdio_bus_suspend,
	422	.thaw = mdio_bus_resume,
	423	.restore = mdio_bus_restore,
	424	};
	425
	426	#define MDIO_BUS_PM_OPS (&mdio_bus_pm_ops)
	427
	428	#else
	429
	430	#define MDIO_BUS_PM_OPS NULL
	431
	432	#endif /* CONFIG_PM */
	433
56277f40 NB	434	static ssize_t
	435	phy_id_show(struct device dev, struct device_attribute attr, char *buf)
	436	{
	437	struct phy_device *phydev = to_phy_device(dev);
	438
	439	return sprintf(buf, "0x%.8lx\n", (unsigned long)phydev->phy_id);
	440	}
	441
	442	static struct device_attribute mdio_dev_attrs[] = {
	443	__ATTR_RO(phy_id),
	444	__ATTR_NULL
	445	};
	446
00db8189 AF	447	struct bus_type mdio_bus_type = {
	448	.name = "mdio_bus",
	449	.match = mdio_bus_match,
2f5cb434	450	.pm = MDIO_BUS_PM_OPS,
56277f40	451	.dev_attrs = mdio_dev_attrs,
00db8189	452	};
11b0bacd	453	EXPORT_SYMBOL(mdio_bus_type);
00db8189	454
67c4f3fa	455	int __init mdio_bus_init(void)
00db8189	456	{
46abc021 LB	457	int ret;
	458
	459	ret = class_register(&mdio_bus_class);
	460	if (!ret) {
	461	ret = bus_register(&mdio_bus_type);
	462	if (ret)
	463	class_unregister(&mdio_bus_class);
	464	}
	465
	466	return ret;
00db8189 AF	467	}
00db8189 AF	468
dc85dec6	469	void mdio_bus_exit(void)
e1393456	470	{
46abc021	471	class_unregister(&mdio_bus_class);
e1393456 AF	472	bus_unregister(&mdio_bus_type);
e1393456 AF	473	}