[deliverable/linux.git] / 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 <linux/io.h>
#include <linux/uaccess.h>

#include <asm/irq.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);

	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);

	return 0;
}

static const 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 DEVICE_ATTR_RO(phy_id);

static struct attribute *mdio_dev_attrs[] = {
	&dev_attr_phy_id.attr,
	NULL,
};
ATTRIBUTE_GROUPS(mdio_dev);

struct bus_type mdio_bus_type = {
	.name		= "mdio_bus",
	.match		= mdio_bus_match,
	.pm		= MDIO_BUS_PM_OPS,
	.dev_groups	= mdio_dev_groups,
};
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
02d320c3	1	/* MDIO Bus interface
00db8189 AF	2	*
	3	* Author: Andy Fleming
	4	*
	5	* Copyright (c) 2004 Freescale Semiconductor, Inc.
	6	*
	7	* This program is free software; you can redistribute it and/or modify it
	8	* under the terms of the GNU General Public License as published by the
	9	* Free Software Foundation; either version 2 of the License, or (at your
	10	* option) any later version.
	11	*
	12	*/
8d242488 JP	13
	14	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
	15
00db8189	16	#include <linux/kernel.h>
00db8189 AF	17	#include <linux/string.h>
	18	#include <linux/errno.h>
	19	#include <linux/unistd.h>
	20	#include <linux/slab.h>
	21	#include <linux/interrupt.h>
	22	#include <linux/init.h>
	23	#include <linux/delay.h>
3d1e4db2	24	#include <linux/device.h>
a30e2c18	25	#include <linux/of_device.h>
4085a7f0	26	#include <linux/of_mdio.h>
00db8189 AF	27	#include <linux/netdevice.h>
	28	#include <linux/etherdevice.h>
	29	#include <linux/skbuff.h>
	30	#include <linux/spinlock.h>
	31	#include <linux/mm.h>
	32	#include <linux/module.h>
00db8189 AF	33	#include <linux/mii.h>
	34	#include <linux/ethtool.h>
	35	#include <linux/phy.h>
02d320c3 SS	36	#include <linux/io.h>
02d320c3 SS	37	#include <linux/uaccess.h>
00db8189	38
00db8189	39	#include <asm/irq.h>
00db8189	40
298cf9be	41	/**
eb8a54a7	42	* mdiobus_alloc_size - allocate a mii_bus structure
af58f1d6 RD	43	* @size: extra amount of memory to allocate for private storage.
af58f1d6 RD	44	* If non-zero, then bus->priv is points to that memory.
298cf9be LB	45	*
	46	* Description: called by a bus driver to allocate an mii_bus
	47	* structure to fill in.
	48	*/
eb8a54a7	49	struct mii_bus *mdiobus_alloc_size(size_t size)
298cf9be	50	{
46abc021	51	struct mii_bus *bus;
eb8a54a7 TT	52	size_t aligned_size = ALIGN(sizeof(*bus), NETDEV_ALIGN);
	53	size_t alloc_size;
	54
	55	/* If we alloc extra space, it should be aligned */
	56	if (size)
	57	alloc_size = aligned_size + size;
	58	else
	59	alloc_size = sizeof(*bus);
46abc021	60
eb8a54a7 TT	61	bus = kzalloc(alloc_size, GFP_KERNEL);
eb8a54a7 TT	62	if (bus) {
46abc021	63	bus->state = MDIOBUS_ALLOCATED;
eb8a54a7 TT	64	if (size)
	65	bus->priv = (void *)bus + aligned_size;
	66	}
46abc021 LB	67
46abc021 LB	68	return bus;
298cf9be	69	}
eb8a54a7	70	EXPORT_SYMBOL(mdiobus_alloc_size);
298cf9be	71
46abc021 LB	72	/**
46abc021 LB	73	* mdiobus_release - mii_bus device release callback
78c36b15	74	* @d: the target struct device that contains the mii_bus
46abc021 LB	75	*
	76	* Description: called when the last reference to an mii_bus is
	77	* dropped, to free the underlying memory.
	78	*/
	79	static void mdiobus_release(struct device *d)
	80	{
	81	struct mii_bus *bus = to_mii_bus(d);
161c8d2f KH	82	BUG_ON(bus->state != MDIOBUS_RELEASED &&
	83	/* for compatibility with error handling in drivers */
	84	bus->state != MDIOBUS_ALLOCATED);
46abc021 LB	85	kfree(bus);
	86	}
	87
	88	static struct class mdio_bus_class = {
	89	.name = "mdio_bus",
	90	.dev_release = mdiobus_release,
	91	};
	92
b943fbb0	93	#if IS_ENABLED(CONFIG_OF_MDIO)
25106022	94	/* Helper function for of_mdio_find_bus */
9f3b795a	95	static int of_mdio_bus_match(struct device dev, const void mdio_bus_np)
25106022 DD	96	{
	97	return dev->of_node == mdio_bus_np;
	98	}
	99	/**
	100	* of_mdio_find_bus - Given an mii_bus node, find the mii_bus.
f41ef2e7	101	* @mdio_bus_np: Pointer to the mii_bus.
25106022 DD	102	*
	103	* Returns a pointer to the mii_bus, or NULL if none found.
	104	*
	105	* Because the association of a device_node and mii_bus is made via
	106	* of_mdiobus_register(), the mii_bus cannot be found before it is
	107	* registered with of_mdiobus_register().
	108	*
	109	*/
	110	struct mii_bus of_mdio_find_bus(struct device_node mdio_bus_np)
	111	{
	112	struct device *d;
	113
	114	if (!mdio_bus_np)
	115	return NULL;
	116
	117	d = class_find_device(&mdio_bus_class, NULL, mdio_bus_np,
	118	of_mdio_bus_match);
	119
	120	return d ? to_mii_bus(d) : NULL;
	121	}
	122	EXPORT_SYMBOL(of_mdio_find_bus);
	123	#endif
	124
b3df0da8 RD	125	/**
	126	* mdiobus_register - bring up all the PHYs on a given bus and attach them to bus
	127	* @bus: target mii_bus
e1393456	128	*
b3df0da8 RD	129	* Description: Called by a bus driver to bring up all the PHYs
	130	* on a given bus, and attach them to the bus.
	131	*
	132	* Returns 0 on success or < 0 on error.
e1393456 AF	133	*/
	134	int mdiobus_register(struct mii_bus *bus)
	135	{
161c8d2f	136	int i, err;
e1393456	137
e1393456	138	if (NULL == bus \|\| NULL == bus->name \|\|
02d320c3	139	NULL == bus->read \|\| NULL == bus->write)
e1393456 AF	140	return -EINVAL;
e1393456 AF	141
46abc021 LB	142	BUG_ON(bus->state != MDIOBUS_ALLOCATED &&
	143	bus->state != MDIOBUS_UNREGISTERED);
	144
	145	bus->dev.parent = bus->parent;
	146	bus->dev.class = &mdio_bus_class;
	147	bus->dev.groups = NULL;
036b6687	148	dev_set_name(&bus->dev, "%s", bus->id);
46abc021 LB	149
	150	err = device_register(&bus->dev);
	151	if (err) {
8d242488	152	pr_err("mii_bus %s failed to register\n", bus->id);
46abc021 LB	153	return -EINVAL;
	154	}
	155
d1e7fe4d AB	156	mutex_init(&bus->mdio_lock);
d1e7fe4d AB	157
e1393456 AF	158	if (bus->reset)
	159	bus->reset(bus);
	160
	161	for (i = 0; i < PHY_MAX_ADDR; i++) {
4fd5f812 LB	162	if ((bus->phy_mask & (1 << i)) == 0) {
4fd5f812 LB	163	struct phy_device *phydev;
e1393456	164
4fd5f812	165	phydev = mdiobus_scan(bus, i);
161c8d2f	166	if (IS_ERR(phydev)) {
4fd5f812	167	err = PTR_ERR(phydev);
161c8d2f KH	168	goto error;
161c8d2f KH	169	}
64b1c2b4	170	}
e1393456 AF	171	}
e1393456 AF	172
161c8d2f	173	bus->state = MDIOBUS_REGISTERED;
e1393456	174	pr_info("%s: probed\n", bus->name);
161c8d2f	175	return 0;
e1393456	176
161c8d2f KH	177	error:
	178	while (--i >= 0) {
	179	if (bus->phy_map[i])
	180	device_unregister(&bus->phy_map[i]->dev);
	181	}
	182	device_del(&bus->dev);
e1393456 AF	183	return err;
	184	}
	185	EXPORT_SYMBOL(mdiobus_register);
	186
	187	void mdiobus_unregister(struct mii_bus *bus)
	188	{
	189	int i;
	190
46abc021 LB	191	BUG_ON(bus->state != MDIOBUS_REGISTERED);
	192	bus->state = MDIOBUS_UNREGISTERED;
	193
3e44017b	194	device_del(&bus->dev);
e1393456	195	for (i = 0; i < PHY_MAX_ADDR; i++) {
6f4a7f41	196	if (bus->phy_map[i])
e1393456	197	device_unregister(&bus->phy_map[i]->dev);
4dea547f	198	bus->phy_map[i] = NULL;
e1393456 AF	199	}
	200	}
	201	EXPORT_SYMBOL(mdiobus_unregister);
	202
298cf9be LB	203	/**
	204	* mdiobus_free - free a struct mii_bus
	205	* @bus: mii_bus to free
	206	*
46abc021 LB	207	* This function releases the reference to the underlying device
	208	* object in the mii_bus. If this is the last reference, the mii_bus
	209	* will be freed.
298cf9be LB	210	*/
	211	void mdiobus_free(struct mii_bus *bus)
	212	{
02d320c3	213	/* For compatibility with error handling in drivers. */
46abc021 LB	214	if (bus->state == MDIOBUS_ALLOCATED) {
	215	kfree(bus);
	216	return;
	217	}
	218
	219	BUG_ON(bus->state != MDIOBUS_UNREGISTERED);
	220	bus->state = MDIOBUS_RELEASED;
	221
	222	put_device(&bus->dev);
298cf9be LB	223	}
	224	EXPORT_SYMBOL(mdiobus_free);
	225
4fd5f812 LB	226	struct phy_device mdiobus_scan(struct mii_bus bus, int addr)
	227	{
	228	struct phy_device *phydev;
	229	int err;
	230
ac28b9f8	231	phydev = get_phy_device(bus, addr, false);
4fd5f812 LB	232	if (IS_ERR(phydev) \|\| phydev == NULL)
	233	return phydev;
	234
4dea547f	235	err = phy_device_register(phydev);
4fd5f812	236	if (err) {
4fd5f812	237	phy_device_free(phydev);
4dea547f	238	return NULL;
4fd5f812 LB	239	}
4fd5f812 LB	240
4fd5f812 LB	241	return phydev;
	242	}
	243	EXPORT_SYMBOL(mdiobus_scan);
	244
2e888103 LB	245	/**
	246	* mdiobus_read - Convenience function for reading a given MII mgmt register
	247	* @bus: the mii_bus struct
	248	* @addr: the phy address
	249	* @regnum: register number to read
	250	*
	251	* NOTE: MUST NOT be called from interrupt context,
	252	* because the bus read/write functions may wait for an interrupt
	253	* to conclude the operation.
	254	*/
abf35df2	255	int mdiobus_read(struct mii_bus *bus, int addr, u32 regnum)
2e888103 LB	256	{
	257	int retval;
	258
	259	BUG_ON(in_interrupt());
	260
	261	mutex_lock(&bus->mdio_lock);
	262	retval = bus->read(bus, addr, regnum);
	263	mutex_unlock(&bus->mdio_lock);
	264
	265	return retval;
	266	}
	267	EXPORT_SYMBOL(mdiobus_read);
	268
	269	/**
	270	* mdiobus_write - Convenience function for writing a given MII mgmt register
	271	* @bus: the mii_bus struct
	272	* @addr: the phy address
	273	* @regnum: register number to write
	274	* @val: value to write to @regnum
	275	*
	276	* NOTE: MUST NOT be called from interrupt context,
	277	* because the bus read/write functions may wait for an interrupt
	278	* to conclude the operation.
	279	*/
abf35df2	280	int mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val)
2e888103 LB	281	{
	282	int err;
	283
	284	BUG_ON(in_interrupt());
	285
	286	mutex_lock(&bus->mdio_lock);
	287	err = bus->write(bus, addr, regnum, val);
	288	mutex_unlock(&bus->mdio_lock);
	289
	290	return err;
	291	}
	292	EXPORT_SYMBOL(mdiobus_write);
	293
b3df0da8 RD	294	/**
	295	* mdio_bus_match - determine if given PHY driver supports the given PHY device
	296	* @dev: target PHY device
	297	* @drv: given PHY driver
00db8189	298	*
b3df0da8 RD	299	* Description: Given a PHY device, and a PHY driver, return 1 if
b3df0da8 RD	300	* the driver supports the device. Otherwise, return 0.
00db8189 AF	301	*/
	302	static int mdio_bus_match(struct device dev, struct device_driver drv)
	303	{
	304	struct phy_device *phydev = to_phy_device(dev);
	305	struct phy_driver *phydrv = to_phy_driver(drv);
	306
a30e2c18 DD	307	if (of_driver_match_device(dev, drv))
	308	return 1;
	309
	310	if (phydrv->match_phy_device)
	311	return phydrv->match_phy_device(phydev);
	312
6f901b73 FF	313	return (phydrv->phy_id & phydrv->phy_id_mask) ==
6f901b73 FF	314	(phydev->phy_id & phydrv->phy_id_mask);
00db8189 AF	315	}
00db8189 AF	316
2f5cb434 AV	317	#ifdef CONFIG_PM
2f5cb434 AV	318
3d1e4db2 AV	319	static bool mdio_bus_phy_may_suspend(struct phy_device *phydev)
	320	{
	321	struct device_driver *drv = phydev->dev.driver;
	322	struct phy_driver *phydrv = to_phy_driver(drv);
	323	struct net_device *netdev = phydev->attached_dev;
	324
	325	if (!drv \|\| !phydrv->suspend)
	326	return false;
	327
	328	/* PHY not attached? May suspend. */
	329	if (!netdev)
	330	return true;
	331
02d320c3	332	/* Don't suspend PHY if the attched netdev parent may wakeup.
3d1e4db2 AV	333	* The parent may point to a PCI device, as in tg3 driver.
	334	*/
	335	if (netdev->dev.parent && device_may_wakeup(netdev->dev.parent))
	336	return false;
	337
02d320c3	338	/* Also don't suspend PHY if the netdev itself may wakeup. This
3d1e4db2 AV	339	* is the case for devices w/o underlaying pwr. mgmt. aware bus,
	340	* e.g. SoC devices.
	341	*/
	342	if (device_may_wakeup(&netdev->dev))
	343	return false;
	344
	345	return true;
	346	}
	347
2f5cb434	348	static int mdio_bus_suspend(struct device *dev)
00db8189	349	{
3d1e4db2	350	struct phy_driver *phydrv = to_phy_driver(dev->driver);
0f0ca340	351	struct phy_device *phydev = to_phy_device(dev);
00db8189	352
02d320c3	353	/* We must stop the state machine manually, otherwise it stops out of
541cd3ee AV	354	* control, possibly with the phydev->lock held. Upon resume, netdev
	355	* may call phy routines that try to grab the same lock, and that may
	356	* lead to a deadlock.
	357	*/
fddd9101	358	if (phydev->attached_dev && phydev->adjust_link)
541cd3ee AV	359	phy_stop_machine(phydev);
541cd3ee AV	360
3d1e4db2 AV	361	if (!mdio_bus_phy_may_suspend(phydev))
3d1e4db2 AV	362	return 0;
541cd3ee	363
3d1e4db2	364	return phydrv->suspend(phydev);
00db8189 AF	365	}
00db8189 AF	366
2f5cb434	367	static int mdio_bus_resume(struct device *dev)
00db8189	368	{
3d1e4db2	369	struct phy_driver *phydrv = to_phy_driver(dev->driver);
0f0ca340	370	struct phy_device *phydev = to_phy_device(dev);
541cd3ee	371	int ret;
00db8189	372
3d1e4db2	373	if (!mdio_bus_phy_may_suspend(phydev))
541cd3ee AV	374	goto no_resume;
	375
	376	ret = phydrv->resume(phydev);
	377	if (ret < 0)
	378	return ret;
	379
	380	no_resume:
fddd9101	381	if (phydev->attached_dev && phydev->adjust_link)
29935aeb	382	phy_start_machine(phydev);
541cd3ee AV	383
541cd3ee AV	384	return 0;
00db8189 AF	385	}
00db8189 AF	386
2f5cb434 AV	387	static int mdio_bus_restore(struct device *dev)
	388	{
	389	struct phy_device *phydev = to_phy_device(dev);
	390	struct net_device *netdev = phydev->attached_dev;
	391	int ret;
	392
	393	if (!netdev)
	394	return 0;
	395
	396	ret = phy_init_hw(phydev);
	397	if (ret < 0)
	398	return ret;
	399
	400	/* The PHY needs to renegotiate. */
	401	phydev->link = 0;
	402	phydev->state = PHY_UP;
	403
29935aeb	404	phy_start_machine(phydev);
2f5cb434 AV	405
	406	return 0;
	407	}
	408
02d320c3	409	static const struct dev_pm_ops mdio_bus_pm_ops = {
2f5cb434 AV	410	.suspend = mdio_bus_suspend,
	411	.resume = mdio_bus_resume,
	412	.freeze = mdio_bus_suspend,
	413	.thaw = mdio_bus_resume,
	414	.restore = mdio_bus_restore,
	415	};
	416
	417	#define MDIO_BUS_PM_OPS (&mdio_bus_pm_ops)
	418
	419	#else
	420
	421	#define MDIO_BUS_PM_OPS NULL
	422
	423	#endif /* CONFIG_PM */
	424
56277f40 NB	425	static ssize_t
	426	phy_id_show(struct device dev, struct device_attribute attr, char *buf)
	427	{
	428	struct phy_device *phydev = to_phy_device(dev);
	429
	430	return sprintf(buf, "0x%.8lx\n", (unsigned long)phydev->phy_id);
	431	}
4192c749	432	static DEVICE_ATTR_RO(phy_id);
56277f40	433
4192c749 GKH	434	static struct attribute *mdio_dev_attrs[] = {
	435	&dev_attr_phy_id.attr,
	436	NULL,
56277f40	437	};
4192c749	438	ATTRIBUTE_GROUPS(mdio_dev);
56277f40	439
00db8189 AF	440	struct bus_type mdio_bus_type = {
	441	.name = "mdio_bus",
	442	.match = mdio_bus_match,
2f5cb434	443	.pm = MDIO_BUS_PM_OPS,
4192c749	444	.dev_groups = mdio_dev_groups,
00db8189	445	};
11b0bacd	446	EXPORT_SYMBOL(mdio_bus_type);
00db8189	447
67c4f3fa	448	int __init mdio_bus_init(void)
00db8189	449	{
46abc021 LB	450	int ret;
	451
	452	ret = class_register(&mdio_bus_class);
	453	if (!ret) {
	454	ret = bus_register(&mdio_bus_type);
	455	if (ret)
	456	class_unregister(&mdio_bus_class);
	457	}
	458
	459	return ret;
00db8189 AF	460	}
00db8189 AF	461
dc85dec6	462	void mdio_bus_exit(void)
e1393456	463	{
46abc021	464	class_unregister(&mdio_bus_class);
e1393456 AF	465	bus_unregister(&mdio_bus_type);
e1393456 AF	466	}