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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}
v3.15
  1/* MDIO Bus interface
 
 
 
  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 */
 13
 14#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 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/of_device.h>
 26#include <linux/of_mdio.h>
 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>
 33#include <linux/mii.h>
 34#include <linux/ethtool.h>
 35#include <linux/phy.h>
 36#include <linux/io.h>
 37#include <linux/uaccess.h>
 38
 
 39#include <asm/irq.h>
 
 40
 41/**
 42 * mdiobus_alloc_size - allocate a mii_bus structure
 43 * @size: extra amount of memory to allocate for private storage.
 44 * If non-zero, then bus->priv is points to that memory.
 45 *
 46 * Description: called by a bus driver to allocate an mii_bus
 47 * structure to fill in.
 48 */
 49struct mii_bus *mdiobus_alloc_size(size_t size)
 50{
 51	struct mii_bus *bus;
 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);
 60
 61	bus = kzalloc(alloc_size, GFP_KERNEL);
 62	if (bus) {
 63		bus->state = MDIOBUS_ALLOCATED;
 64		if (size)
 65			bus->priv = (void *)bus + aligned_size;
 66	}
 67
 68	return bus;
 69}
 70EXPORT_SYMBOL(mdiobus_alloc_size);
 71
 72/**
 73 * mdiobus_release - mii_bus device release callback
 74 * @d: the target struct device that contains the mii_bus
 75 *
 76 * Description: called when the last reference to an mii_bus is
 77 * dropped, to free the underlying memory.
 78 */
 79static void mdiobus_release(struct device *d)
 80{
 81	struct mii_bus *bus = to_mii_bus(d);
 82	BUG_ON(bus->state != MDIOBUS_RELEASED &&
 83	       /* for compatibility with error handling in drivers */
 84	       bus->state != MDIOBUS_ALLOCATED);
 85	kfree(bus);
 86}
 87
 88static struct class mdio_bus_class = {
 89	.name		= "mdio_bus",
 90	.dev_release	= mdiobus_release,
 91};
 92
 93#if IS_ENABLED(CONFIG_OF_MDIO)
 94/* Helper function for of_mdio_find_bus */
 95static int of_mdio_bus_match(struct device *dev, const void *mdio_bus_np)
 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.
101 * @mdio_bus_np: Pointer to the mii_bus.
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 */
110struct 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}
122EXPORT_SYMBOL(of_mdio_find_bus);
123#endif
124
125/**
126 * mdiobus_register - bring up all the PHYs on a given bus and attach them to bus
127 * @bus: target mii_bus
128 *
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.
133 */
134int mdiobus_register(struct mii_bus *bus)
135{
136	int i, err;
137
138	if (NULL == bus || NULL == bus->name ||
139	    NULL == bus->read || NULL == bus->write)
 
140		return -EINVAL;
141
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;
148	dev_set_name(&bus->dev, "%s", bus->id);
149
150	err = device_register(&bus->dev);
151	if (err) {
152		pr_err("mii_bus %s failed to register\n", bus->id);
153		put_device(&bus->dev);
154		return -EINVAL;
155	}
156
157	mutex_init(&bus->mdio_lock);
158
159	if (bus->reset)
160		bus->reset(bus);
161
162	for (i = 0; i < PHY_MAX_ADDR; i++) {
163		if ((bus->phy_mask & (1 << i)) == 0) {
164			struct phy_device *phydev;
165
166			phydev = mdiobus_scan(bus, i);
167			if (IS_ERR(phydev)) {
168				err = PTR_ERR(phydev);
169				goto error;
170			}
171		}
172	}
173
174	bus->state = MDIOBUS_REGISTERED;
175	pr_info("%s: probed\n", bus->name);
176	return 0;
177
178error:
179	while (--i >= 0) {
180		if (bus->phy_map[i])
181			device_unregister(&bus->phy_map[i]->dev);
182	}
183	device_del(&bus->dev);
184	return err;
185}
186EXPORT_SYMBOL(mdiobus_register);
187
188void mdiobus_unregister(struct mii_bus *bus)
189{
190	int i;
191
192	BUG_ON(bus->state != MDIOBUS_REGISTERED);
193	bus->state = MDIOBUS_UNREGISTERED;
194
195	device_del(&bus->dev);
196	for (i = 0; i < PHY_MAX_ADDR; i++) {
197		if (bus->phy_map[i])
198			device_unregister(&bus->phy_map[i]->dev);
199		bus->phy_map[i] = NULL;
200	}
201}
202EXPORT_SYMBOL(mdiobus_unregister);
203
204/**
205 * mdiobus_free - free a struct mii_bus
206 * @bus: mii_bus to free
207 *
208 * This function releases the reference to the underlying device
209 * object in the mii_bus.  If this is the last reference, the mii_bus
210 * will be freed.
211 */
212void mdiobus_free(struct mii_bus *bus)
213{
214	/* For compatibility with error handling in drivers. */
 
 
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, false);
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	if (of_driver_match_device(dev, drv))
309		return 1;
310
311	if (phydrv->match_phy_device)
312		return phydrv->match_phy_device(phydev);
313
314	return (phydrv->phy_id & phydrv->phy_id_mask) ==
315		(phydev->phy_id & phydrv->phy_id_mask);
316}
317
318#ifdef CONFIG_PM
319
320static bool mdio_bus_phy_may_suspend(struct phy_device *phydev)
321{
322	struct device_driver *drv = phydev->dev.driver;
323	struct phy_driver *phydrv = to_phy_driver(drv);
324	struct net_device *netdev = phydev->attached_dev;
325
326	if (!drv || !phydrv->suspend)
327		return false;
328
329	/* PHY not attached? May suspend. */
330	if (!netdev)
331		return true;
332
333	/* Don't suspend PHY if the attched netdev parent may wakeup.
 
334	 * The parent may point to a PCI device, as in tg3 driver.
335	 */
336	if (netdev->dev.parent && device_may_wakeup(netdev->dev.parent))
337		return false;
338
339	/* Also don't suspend PHY if the netdev itself may wakeup. This
 
340	 * is the case for devices w/o underlaying pwr. mgmt. aware bus,
341	 * e.g. SoC devices.
342	 */
343	if (device_may_wakeup(&netdev->dev))
344		return false;
345
346	return true;
347}
348
349static int mdio_bus_suspend(struct device *dev)
350{
351	struct phy_driver *phydrv = to_phy_driver(dev->driver);
352	struct phy_device *phydev = to_phy_device(dev);
353
354	/* We must stop the state machine manually, otherwise it stops out of
 
355	 * control, possibly with the phydev->lock held. Upon resume, netdev
356	 * may call phy routines that try to grab the same lock, and that may
357	 * lead to a deadlock.
358	 */
359	if (phydev->attached_dev && phydev->adjust_link)
360		phy_stop_machine(phydev);
361
362	if (!mdio_bus_phy_may_suspend(phydev))
363		return 0;
364
365	return phydrv->suspend(phydev);
366}
367
368static int mdio_bus_resume(struct device *dev)
369{
370	struct phy_driver *phydrv = to_phy_driver(dev->driver);
371	struct phy_device *phydev = to_phy_device(dev);
372	int ret;
373
374	if (!mdio_bus_phy_may_suspend(phydev))
375		goto no_resume;
376
377	ret = phydrv->resume(phydev);
378	if (ret < 0)
379		return ret;
380
381no_resume:
382	if (phydev->attached_dev && phydev->adjust_link)
383		phy_start_machine(phydev);
384
385	return 0;
386}
387
388static int mdio_bus_restore(struct device *dev)
389{
390	struct phy_device *phydev = to_phy_device(dev);
391	struct net_device *netdev = phydev->attached_dev;
392	int ret;
393
394	if (!netdev)
395		return 0;
396
397	ret = phy_init_hw(phydev);
398	if (ret < 0)
399		return ret;
400
401	/* The PHY needs to renegotiate. */
402	phydev->link = 0;
403	phydev->state = PHY_UP;
404
405	phy_start_machine(phydev);
406
407	return 0;
408}
409
410static const struct dev_pm_ops mdio_bus_pm_ops = {
411	.suspend = mdio_bus_suspend,
412	.resume = mdio_bus_resume,
413	.freeze = mdio_bus_suspend,
414	.thaw = mdio_bus_resume,
415	.restore = mdio_bus_restore,
416};
417
418#define MDIO_BUS_PM_OPS (&mdio_bus_pm_ops)
419
420#else
421
422#define MDIO_BUS_PM_OPS NULL
423
424#endif /* CONFIG_PM */
425
426static ssize_t
427phy_id_show(struct device *dev, struct device_attribute *attr, char *buf)
428{
429	struct phy_device *phydev = to_phy_device(dev);
430
431	return sprintf(buf, "0x%.8lx\n", (unsigned long)phydev->phy_id);
432}
433static DEVICE_ATTR_RO(phy_id);
434
435static ssize_t
436phy_interface_show(struct device *dev, struct device_attribute *attr, char *buf)
437{
438	struct phy_device *phydev = to_phy_device(dev);
439
440	return sprintf(buf, "%s\n", phy_modes(phydev->interface));
441}
442static DEVICE_ATTR_RO(phy_interface);
443
444static ssize_t
445phy_has_fixups_show(struct device *dev, struct device_attribute *attr, char *buf)
446{
447	struct phy_device *phydev = to_phy_device(dev);
448
449	return sprintf(buf, "%d\n", phydev->has_fixups);
450}
451static DEVICE_ATTR_RO(phy_has_fixups);
452
453static struct attribute *mdio_dev_attrs[] = {
454	&dev_attr_phy_id.attr,
455	&dev_attr_phy_interface.attr,
456	&dev_attr_phy_has_fixups.attr,
457	NULL,
458};
459ATTRIBUTE_GROUPS(mdio_dev);
460
461struct bus_type mdio_bus_type = {
462	.name		= "mdio_bus",
463	.match		= mdio_bus_match,
464	.pm		= MDIO_BUS_PM_OPS,
465	.dev_groups	= mdio_dev_groups,
466};
467EXPORT_SYMBOL(mdio_bus_type);
468
469int __init mdio_bus_init(void)
470{
471	int ret;
472
473	ret = class_register(&mdio_bus_class);
474	if (!ret) {
475		ret = bus_register(&mdio_bus_type);
476		if (ret)
477			class_unregister(&mdio_bus_class);
478	}
479
480	return ret;
481}
482
483void mdio_bus_exit(void)
484{
485	class_unregister(&mdio_bus_class);
486	bus_unregister(&mdio_bus_type);
487}