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v3.1
  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 */
 16#include <linux/kernel.h>
 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>
 24#include <linux/device.h>
 25#include <linux/netdevice.h>
 26#include <linux/etherdevice.h>
 27#include <linux/skbuff.h>
 28#include <linux/spinlock.h>
 29#include <linux/mm.h>
 30#include <linux/module.h>
 31#include <linux/mii.h>
 32#include <linux/ethtool.h>
 33#include <linux/phy.h>
 34
 35#include <asm/io.h>
 36#include <asm/irq.h>
 37#include <asm/uaccess.h>
 38
 39/**
 40 * mdiobus_alloc - allocate a mii_bus structure
 
 
 41 *
 42 * Description: called by a bus driver to allocate an mii_bus
 43 * structure to fill in.
 44 */
 45struct mii_bus *mdiobus_alloc(void)
 46{
 47	struct mii_bus *bus;
 
 
 48
 49	bus = kzalloc(sizeof(*bus), GFP_KERNEL);
 50	if (bus != NULL)
 
 
 
 
 
 
 51		bus->state = MDIOBUS_ALLOCATED;
 
 
 
 52
 53	return bus;
 54}
 55EXPORT_SYMBOL(mdiobus_alloc);
 56
 57/**
 58 * mdiobus_release - mii_bus device release callback
 59 * @d: the target struct device that contains the mii_bus
 60 *
 61 * Description: called when the last reference to an mii_bus is
 62 * dropped, to free the underlying memory.
 63 */
 64static void mdiobus_release(struct device *d)
 65{
 66	struct mii_bus *bus = to_mii_bus(d);
 67	BUG_ON(bus->state != MDIOBUS_RELEASED &&
 68	       /* for compatibility with error handling in drivers */
 69	       bus->state != MDIOBUS_ALLOCATED);
 70	kfree(bus);
 71}
 72
 73static struct class mdio_bus_class = {
 74	.name		= "mdio_bus",
 75	.dev_release	= mdiobus_release,
 76};
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 77
 78/**
 79 * mdiobus_register - bring up all the PHYs on a given bus and attach them to bus
 80 * @bus: target mii_bus
 81 *
 82 * Description: Called by a bus driver to bring up all the PHYs
 83 *   on a given bus, and attach them to the bus.
 84 *
 85 * Returns 0 on success or < 0 on error.
 86 */
 87int mdiobus_register(struct mii_bus *bus)
 88{
 89	int i, err;
 90
 91	if (NULL == bus || NULL == bus->name ||
 92			NULL == bus->read ||
 93			NULL == bus->write)
 94		return -EINVAL;
 95
 96	BUG_ON(bus->state != MDIOBUS_ALLOCATED &&
 97	       bus->state != MDIOBUS_UNREGISTERED);
 98
 99	bus->dev.parent = bus->parent;
100	bus->dev.class = &mdio_bus_class;
101	bus->dev.groups = NULL;
102	dev_set_name(&bus->dev, "%s", bus->id);
103
104	err = device_register(&bus->dev);
105	if (err) {
106		printk(KERN_ERR "mii_bus %s failed to register\n", bus->id);
107		return -EINVAL;
108	}
109
110	mutex_init(&bus->mdio_lock);
111
112	if (bus->reset)
113		bus->reset(bus);
114
115	for (i = 0; i < PHY_MAX_ADDR; i++) {
116		if ((bus->phy_mask & (1 << i)) == 0) {
117			struct phy_device *phydev;
118
119			phydev = mdiobus_scan(bus, i);
120			if (IS_ERR(phydev)) {
121				err = PTR_ERR(phydev);
122				goto error;
123			}
124		}
125	}
126
127	bus->state = MDIOBUS_REGISTERED;
128	pr_info("%s: probed\n", bus->name);
129	return 0;
130
131error:
132	while (--i >= 0) {
133		if (bus->phy_map[i])
134			device_unregister(&bus->phy_map[i]->dev);
135	}
136	device_del(&bus->dev);
137	return err;
138}
139EXPORT_SYMBOL(mdiobus_register);
140
141void mdiobus_unregister(struct mii_bus *bus)
142{
143	int i;
144
145	BUG_ON(bus->state != MDIOBUS_REGISTERED);
146	bus->state = MDIOBUS_UNREGISTERED;
147
148	device_del(&bus->dev);
149	for (i = 0; i < PHY_MAX_ADDR; i++) {
150		if (bus->phy_map[i])
151			device_unregister(&bus->phy_map[i]->dev);
152		bus->phy_map[i] = NULL;
153	}
154}
155EXPORT_SYMBOL(mdiobus_unregister);
156
157/**
158 * mdiobus_free - free a struct mii_bus
159 * @bus: mii_bus to free
160 *
161 * This function releases the reference to the underlying device
162 * object in the mii_bus.  If this is the last reference, the mii_bus
163 * will be freed.
164 */
165void mdiobus_free(struct mii_bus *bus)
166{
167	/*
168	 * For compatibility with error handling in drivers.
169	 */
170	if (bus->state == MDIOBUS_ALLOCATED) {
171		kfree(bus);
172		return;
173	}
174
175	BUG_ON(bus->state != MDIOBUS_UNREGISTERED);
176	bus->state = MDIOBUS_RELEASED;
177
178	put_device(&bus->dev);
179}
180EXPORT_SYMBOL(mdiobus_free);
181
182struct phy_device *mdiobus_scan(struct mii_bus *bus, int addr)
183{
184	struct phy_device *phydev;
185	int err;
186
187	phydev = get_phy_device(bus, addr);
188	if (IS_ERR(phydev) || phydev == NULL)
189		return phydev;
190
191	err = phy_device_register(phydev);
192	if (err) {
193		phy_device_free(phydev);
194		return NULL;
195	}
196
197	return phydev;
198}
199EXPORT_SYMBOL(mdiobus_scan);
200
201/**
202 * mdiobus_read - Convenience function for reading a given MII mgmt register
203 * @bus: the mii_bus struct
204 * @addr: the phy address
205 * @regnum: register number to read
206 *
207 * NOTE: MUST NOT be called from interrupt context,
208 * because the bus read/write functions may wait for an interrupt
209 * to conclude the operation.
210 */
211int mdiobus_read(struct mii_bus *bus, int addr, u32 regnum)
212{
213	int retval;
214
215	BUG_ON(in_interrupt());
216
217	mutex_lock(&bus->mdio_lock);
218	retval = bus->read(bus, addr, regnum);
219	mutex_unlock(&bus->mdio_lock);
220
221	return retval;
222}
223EXPORT_SYMBOL(mdiobus_read);
224
225/**
226 * mdiobus_write - Convenience function for writing a given MII mgmt register
227 * @bus: the mii_bus struct
228 * @addr: the phy address
229 * @regnum: register number to write
230 * @val: value to write to @regnum
231 *
232 * NOTE: MUST NOT be called from interrupt context,
233 * because the bus read/write functions may wait for an interrupt
234 * to conclude the operation.
235 */
236int mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val)
237{
238	int err;
239
240	BUG_ON(in_interrupt());
241
242	mutex_lock(&bus->mdio_lock);
243	err = bus->write(bus, addr, regnum, val);
244	mutex_unlock(&bus->mdio_lock);
245
246	return err;
247}
248EXPORT_SYMBOL(mdiobus_write);
249
250/**
251 * mdio_bus_match - determine if given PHY driver supports the given PHY device
252 * @dev: target PHY device
253 * @drv: given PHY driver
254 *
255 * Description: Given a PHY device, and a PHY driver, return 1 if
256 *   the driver supports the device.  Otherwise, return 0.
257 */
258static int mdio_bus_match(struct device *dev, struct device_driver *drv)
259{
260	struct phy_device *phydev = to_phy_device(dev);
261	struct phy_driver *phydrv = to_phy_driver(drv);
262
263	return ((phydrv->phy_id & phydrv->phy_id_mask) ==
264		(phydev->phy_id & phydrv->phy_id_mask));
265}
266
267#ifdef CONFIG_PM
268
269static bool mdio_bus_phy_may_suspend(struct phy_device *phydev)
270{
271	struct device_driver *drv = phydev->dev.driver;
272	struct phy_driver *phydrv = to_phy_driver(drv);
273	struct net_device *netdev = phydev->attached_dev;
274
275	if (!drv || !phydrv->suspend)
276		return false;
277
278	/* PHY not attached? May suspend. */
279	if (!netdev)
280		return true;
281
282	/*
283	 * Don't suspend PHY if the attched netdev parent may wakeup.
284	 * The parent may point to a PCI device, as in tg3 driver.
285	 */
286	if (netdev->dev.parent && device_may_wakeup(netdev->dev.parent))
287		return false;
288
289	/*
290	 * Also don't suspend PHY if the netdev itself may wakeup. This
291	 * is the case for devices w/o underlaying pwr. mgmt. aware bus,
292	 * e.g. SoC devices.
293	 */
294	if (device_may_wakeup(&netdev->dev))
295		return false;
296
297	return true;
298}
299
300static int mdio_bus_suspend(struct device *dev)
301{
302	struct phy_driver *phydrv = to_phy_driver(dev->driver);
303	struct phy_device *phydev = to_phy_device(dev);
304
305	/*
306	 * We must stop the state machine manually, otherwise it stops out of
307	 * control, possibly with the phydev->lock held. Upon resume, netdev
308	 * may call phy routines that try to grab the same lock, and that may
309	 * lead to a deadlock.
310	 */
311	if (phydev->attached_dev && phydev->adjust_link)
312		phy_stop_machine(phydev);
313
314	if (!mdio_bus_phy_may_suspend(phydev))
315		return 0;
316
317	return phydrv->suspend(phydev);
318}
319
320static int mdio_bus_resume(struct device *dev)
321{
322	struct phy_driver *phydrv = to_phy_driver(dev->driver);
323	struct phy_device *phydev = to_phy_device(dev);
324	int ret;
325
326	if (!mdio_bus_phy_may_suspend(phydev))
327		goto no_resume;
328
329	ret = phydrv->resume(phydev);
330	if (ret < 0)
331		return ret;
332
333no_resume:
334	if (phydev->attached_dev && phydev->adjust_link)
335		phy_start_machine(phydev, NULL);
336
337	return 0;
338}
339
340static int mdio_bus_restore(struct device *dev)
341{
342	struct phy_device *phydev = to_phy_device(dev);
343	struct net_device *netdev = phydev->attached_dev;
344	int ret;
345
346	if (!netdev)
347		return 0;
348
349	ret = phy_init_hw(phydev);
350	if (ret < 0)
351		return ret;
352
353	/* The PHY needs to renegotiate. */
354	phydev->link = 0;
355	phydev->state = PHY_UP;
356
357	phy_start_machine(phydev, NULL);
358
359	return 0;
360}
361
362static struct dev_pm_ops mdio_bus_pm_ops = {
363	.suspend = mdio_bus_suspend,
364	.resume = mdio_bus_resume,
365	.freeze = mdio_bus_suspend,
366	.thaw = mdio_bus_resume,
367	.restore = mdio_bus_restore,
368};
369
370#define MDIO_BUS_PM_OPS (&mdio_bus_pm_ops)
371
372#else
373
374#define MDIO_BUS_PM_OPS NULL
375
376#endif /* CONFIG_PM */
377
378struct bus_type mdio_bus_type = {
379	.name		= "mdio_bus",
380	.match		= mdio_bus_match,
381	.pm		= MDIO_BUS_PM_OPS,
382};
383EXPORT_SYMBOL(mdio_bus_type);
384
385int __init mdio_bus_init(void)
386{
387	int ret;
388
389	ret = class_register(&mdio_bus_class);
390	if (!ret) {
391		ret = bus_register(&mdio_bus_type);
392		if (ret)
393			class_unregister(&mdio_bus_class);
394	}
395
396	return ret;
397}
398
399void mdio_bus_exit(void)
400{
401	class_unregister(&mdio_bus_class);
402	bus_unregister(&mdio_bus_type);
403}
v3.5.6
  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 */
 16#include <linux/kernel.h>
 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>
 24#include <linux/device.h>
 25#include <linux/netdevice.h>
 26#include <linux/etherdevice.h>
 27#include <linux/skbuff.h>
 28#include <linux/spinlock.h>
 29#include <linux/mm.h>
 30#include <linux/module.h>
 31#include <linux/mii.h>
 32#include <linux/ethtool.h>
 33#include <linux/phy.h>
 34
 35#include <asm/io.h>
 36#include <asm/irq.h>
 37#include <asm/uaccess.h>
 38
 39/**
 40 * mdiobus_alloc_size - allocate a mii_bus structure
 41 * @size: extra amount of memory to allocate for private storage.
 42 * If non-zero, then bus->priv is points to that memory.
 43 *
 44 * Description: called by a bus driver to allocate an mii_bus
 45 * structure to fill in.
 46 */
 47struct mii_bus *mdiobus_alloc_size(size_t size)
 48{
 49	struct mii_bus *bus;
 50	size_t aligned_size = ALIGN(sizeof(*bus), NETDEV_ALIGN);
 51	size_t alloc_size;
 52
 53	/* If we alloc extra space, it should be aligned */
 54	if (size)
 55		alloc_size = aligned_size + size;
 56	else
 57		alloc_size = sizeof(*bus);
 58
 59	bus = kzalloc(alloc_size, GFP_KERNEL);
 60	if (bus) {
 61		bus->state = MDIOBUS_ALLOCATED;
 62		if (size)
 63			bus->priv = (void *)bus + aligned_size;
 64	}
 65
 66	return bus;
 67}
 68EXPORT_SYMBOL(mdiobus_alloc_size);
 69
 70/**
 71 * mdiobus_release - mii_bus device release callback
 72 * @d: the target struct device that contains the mii_bus
 73 *
 74 * Description: called when the last reference to an mii_bus is
 75 * dropped, to free the underlying memory.
 76 */
 77static void mdiobus_release(struct device *d)
 78{
 79	struct mii_bus *bus = to_mii_bus(d);
 80	BUG_ON(bus->state != MDIOBUS_RELEASED &&
 81	       /* for compatibility with error handling in drivers */
 82	       bus->state != MDIOBUS_ALLOCATED);
 83	kfree(bus);
 84}
 85
 86static struct class mdio_bus_class = {
 87	.name		= "mdio_bus",
 88	.dev_release	= mdiobus_release,
 89};
 90
 91#if IS_ENABLED(CONFIG_OF_MDIO)
 92/* Helper function for of_mdio_find_bus */
 93static int of_mdio_bus_match(struct device *dev, void *mdio_bus_np)
 94{
 95	return dev->of_node == mdio_bus_np;
 96}
 97/**
 98 * of_mdio_find_bus - Given an mii_bus node, find the mii_bus.
 99 * @mdio_bus_np: Pointer to the mii_bus.
100 *
101 * Returns a pointer to the mii_bus, or NULL if none found.
102 *
103 * Because the association of a device_node and mii_bus is made via
104 * of_mdiobus_register(), the mii_bus cannot be found before it is
105 * registered with of_mdiobus_register().
106 *
107 */
108struct mii_bus *of_mdio_find_bus(struct device_node *mdio_bus_np)
109{
110	struct device *d;
111
112	if (!mdio_bus_np)
113		return NULL;
114
115	d = class_find_device(&mdio_bus_class, NULL,  mdio_bus_np,
116			      of_mdio_bus_match);
117
118	return d ? to_mii_bus(d) : NULL;
119}
120EXPORT_SYMBOL(of_mdio_find_bus);
121#endif
122
123/**
124 * mdiobus_register - bring up all the PHYs on a given bus and attach them to bus
125 * @bus: target mii_bus
126 *
127 * Description: Called by a bus driver to bring up all the PHYs
128 *   on a given bus, and attach them to the bus.
129 *
130 * Returns 0 on success or < 0 on error.
131 */
132int mdiobus_register(struct mii_bus *bus)
133{
134	int i, err;
135
136	if (NULL == bus || NULL == bus->name ||
137			NULL == bus->read ||
138			NULL == bus->write)
139		return -EINVAL;
140
141	BUG_ON(bus->state != MDIOBUS_ALLOCATED &&
142	       bus->state != MDIOBUS_UNREGISTERED);
143
144	bus->dev.parent = bus->parent;
145	bus->dev.class = &mdio_bus_class;
146	bus->dev.groups = NULL;
147	dev_set_name(&bus->dev, "%s", bus->id);
148
149	err = device_register(&bus->dev);
150	if (err) {
151		printk(KERN_ERR "mii_bus %s failed to register\n", bus->id);
152		return -EINVAL;
153	}
154
155	mutex_init(&bus->mdio_lock);
156
157	if (bus->reset)
158		bus->reset(bus);
159
160	for (i = 0; i < PHY_MAX_ADDR; i++) {
161		if ((bus->phy_mask & (1 << i)) == 0) {
162			struct phy_device *phydev;
163
164			phydev = mdiobus_scan(bus, i);
165			if (IS_ERR(phydev)) {
166				err = PTR_ERR(phydev);
167				goto error;
168			}
169		}
170	}
171
172	bus->state = MDIOBUS_REGISTERED;
173	pr_info("%s: probed\n", bus->name);
174	return 0;
175
176error:
177	while (--i >= 0) {
178		if (bus->phy_map[i])
179			device_unregister(&bus->phy_map[i]->dev);
180	}
181	device_del(&bus->dev);
182	return err;
183}
184EXPORT_SYMBOL(mdiobus_register);
185
186void mdiobus_unregister(struct mii_bus *bus)
187{
188	int i;
189
190	BUG_ON(bus->state != MDIOBUS_REGISTERED);
191	bus->state = MDIOBUS_UNREGISTERED;
192
193	device_del(&bus->dev);
194	for (i = 0; i < PHY_MAX_ADDR; i++) {
195		if (bus->phy_map[i])
196			device_unregister(&bus->phy_map[i]->dev);
197		bus->phy_map[i] = NULL;
198	}
199}
200EXPORT_SYMBOL(mdiobus_unregister);
201
202/**
203 * mdiobus_free - free a struct mii_bus
204 * @bus: mii_bus to free
205 *
206 * This function releases the reference to the underlying device
207 * object in the mii_bus.  If this is the last reference, the mii_bus
208 * will be freed.
209 */
210void mdiobus_free(struct mii_bus *bus)
211{
212	/*
213	 * For compatibility with error handling in drivers.
214	 */
215	if (bus->state == MDIOBUS_ALLOCATED) {
216		kfree(bus);
217		return;
218	}
219
220	BUG_ON(bus->state != MDIOBUS_UNREGISTERED);
221	bus->state = MDIOBUS_RELEASED;
222
223	put_device(&bus->dev);
224}
225EXPORT_SYMBOL(mdiobus_free);
226
227struct phy_device *mdiobus_scan(struct mii_bus *bus, int addr)
228{
229	struct phy_device *phydev;
230	int err;
231
232	phydev = get_phy_device(bus, addr);
233	if (IS_ERR(phydev) || phydev == NULL)
234		return phydev;
235
236	err = phy_device_register(phydev);
237	if (err) {
238		phy_device_free(phydev);
239		return NULL;
240	}
241
242	return phydev;
243}
244EXPORT_SYMBOL(mdiobus_scan);
245
246/**
247 * mdiobus_read - Convenience function for reading a given MII mgmt register
248 * @bus: the mii_bus struct
249 * @addr: the phy address
250 * @regnum: register number to read
251 *
252 * NOTE: MUST NOT be called from interrupt context,
253 * because the bus read/write functions may wait for an interrupt
254 * to conclude the operation.
255 */
256int mdiobus_read(struct mii_bus *bus, int addr, u32 regnum)
257{
258	int retval;
259
260	BUG_ON(in_interrupt());
261
262	mutex_lock(&bus->mdio_lock);
263	retval = bus->read(bus, addr, regnum);
264	mutex_unlock(&bus->mdio_lock);
265
266	return retval;
267}
268EXPORT_SYMBOL(mdiobus_read);
269
270/**
271 * mdiobus_write - Convenience function for writing a given MII mgmt register
272 * @bus: the mii_bus struct
273 * @addr: the phy address
274 * @regnum: register number to write
275 * @val: value to write to @regnum
276 *
277 * NOTE: MUST NOT be called from interrupt context,
278 * because the bus read/write functions may wait for an interrupt
279 * to conclude the operation.
280 */
281int mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val)
282{
283	int err;
284
285	BUG_ON(in_interrupt());
286
287	mutex_lock(&bus->mdio_lock);
288	err = bus->write(bus, addr, regnum, val);
289	mutex_unlock(&bus->mdio_lock);
290
291	return err;
292}
293EXPORT_SYMBOL(mdiobus_write);
294
295/**
296 * mdio_bus_match - determine if given PHY driver supports the given PHY device
297 * @dev: target PHY device
298 * @drv: given PHY driver
299 *
300 * Description: Given a PHY device, and a PHY driver, return 1 if
301 *   the driver supports the device.  Otherwise, return 0.
302 */
303static int mdio_bus_match(struct device *dev, struct device_driver *drv)
304{
305	struct phy_device *phydev = to_phy_device(dev);
306	struct phy_driver *phydrv = to_phy_driver(drv);
307
308	return ((phydrv->phy_id & phydrv->phy_id_mask) ==
309		(phydev->phy_id & phydrv->phy_id_mask));
310}
311
312#ifdef CONFIG_PM
313
314static bool mdio_bus_phy_may_suspend(struct phy_device *phydev)
315{
316	struct device_driver *drv = phydev->dev.driver;
317	struct phy_driver *phydrv = to_phy_driver(drv);
318	struct net_device *netdev = phydev->attached_dev;
319
320	if (!drv || !phydrv->suspend)
321		return false;
322
323	/* PHY not attached? May suspend. */
324	if (!netdev)
325		return true;
326
327	/*
328	 * Don't suspend PHY if the attched netdev parent may wakeup.
329	 * The parent may point to a PCI device, as in tg3 driver.
330	 */
331	if (netdev->dev.parent && device_may_wakeup(netdev->dev.parent))
332		return false;
333
334	/*
335	 * Also don't suspend PHY if the netdev itself may wakeup. This
336	 * is the case for devices w/o underlaying pwr. mgmt. aware bus,
337	 * e.g. SoC devices.
338	 */
339	if (device_may_wakeup(&netdev->dev))
340		return false;
341
342	return true;
343}
344
345static int mdio_bus_suspend(struct device *dev)
346{
347	struct phy_driver *phydrv = to_phy_driver(dev->driver);
348	struct phy_device *phydev = to_phy_device(dev);
349
350	/*
351	 * We must stop the state machine manually, otherwise it stops out of
352	 * control, possibly with the phydev->lock held. Upon resume, netdev
353	 * may call phy routines that try to grab the same lock, and that may
354	 * lead to a deadlock.
355	 */
356	if (phydev->attached_dev && phydev->adjust_link)
357		phy_stop_machine(phydev);
358
359	if (!mdio_bus_phy_may_suspend(phydev))
360		return 0;
361
362	return phydrv->suspend(phydev);
363}
364
365static int mdio_bus_resume(struct device *dev)
366{
367	struct phy_driver *phydrv = to_phy_driver(dev->driver);
368	struct phy_device *phydev = to_phy_device(dev);
369	int ret;
370
371	if (!mdio_bus_phy_may_suspend(phydev))
372		goto no_resume;
373
374	ret = phydrv->resume(phydev);
375	if (ret < 0)
376		return ret;
377
378no_resume:
379	if (phydev->attached_dev && phydev->adjust_link)
380		phy_start_machine(phydev, NULL);
381
382	return 0;
383}
384
385static int mdio_bus_restore(struct device *dev)
386{
387	struct phy_device *phydev = to_phy_device(dev);
388	struct net_device *netdev = phydev->attached_dev;
389	int ret;
390
391	if (!netdev)
392		return 0;
393
394	ret = phy_init_hw(phydev);
395	if (ret < 0)
396		return ret;
397
398	/* The PHY needs to renegotiate. */
399	phydev->link = 0;
400	phydev->state = PHY_UP;
401
402	phy_start_machine(phydev, NULL);
403
404	return 0;
405}
406
407static struct dev_pm_ops mdio_bus_pm_ops = {
408	.suspend = mdio_bus_suspend,
409	.resume = mdio_bus_resume,
410	.freeze = mdio_bus_suspend,
411	.thaw = mdio_bus_resume,
412	.restore = mdio_bus_restore,
413};
414
415#define MDIO_BUS_PM_OPS (&mdio_bus_pm_ops)
416
417#else
418
419#define MDIO_BUS_PM_OPS NULL
420
421#endif /* CONFIG_PM */
422
423struct bus_type mdio_bus_type = {
424	.name		= "mdio_bus",
425	.match		= mdio_bus_match,
426	.pm		= MDIO_BUS_PM_OPS,
427};
428EXPORT_SYMBOL(mdio_bus_type);
429
430int __init mdio_bus_init(void)
431{
432	int ret;
433
434	ret = class_register(&mdio_bus_class);
435	if (!ret) {
436		ret = bus_register(&mdio_bus_type);
437		if (ret)
438			class_unregister(&mdio_bus_class);
439	}
440
441	return ret;
442}
443
444void mdio_bus_exit(void)
445{
446	class_unregister(&mdio_bus_class);
447	bus_unregister(&mdio_bus_type);
448}