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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}
1// SPDX-License-Identifier: GPL-2.0+
2/* MDIO Bus interface
3 *
4 * Author: Andy Fleming
5 *
6 * Copyright (c) 2004 Freescale Semiconductor, Inc.
7 */
8
9#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
10
11#include <linux/delay.h>
12#include <linux/device.h>
13#include <linux/errno.h>
14#include <linux/etherdevice.h>
15#include <linux/ethtool.h>
16#include <linux/gpio.h>
17#include <linux/gpio/consumer.h>
18#include <linux/init.h>
19#include <linux/interrupt.h>
20#include <linux/io.h>
21#include <linux/kernel.h>
22#include <linux/mii.h>
23#include <linux/mm.h>
24#include <linux/module.h>
25#include <linux/netdevice.h>
26#include <linux/of_device.h>
27#include <linux/of_gpio.h>
28#include <linux/of_mdio.h>
29#include <linux/phy.h>
30#include <linux/reset.h>
31#include <linux/skbuff.h>
32#include <linux/slab.h>
33#include <linux/spinlock.h>
34#include <linux/string.h>
35#include <linux/uaccess.h>
36#include <linux/unistd.h>
37
38#define CREATE_TRACE_POINTS
39#include <trace/events/mdio.h>
40
41#include "mdio-boardinfo.h"
42
43static int mdiobus_register_gpiod(struct mdio_device *mdiodev)
44{
45 /* Deassert the optional reset signal */
46 mdiodev->reset_gpio = gpiod_get_optional(&mdiodev->dev,
47 "reset", GPIOD_OUT_LOW);
48 if (IS_ERR(mdiodev->reset_gpio))
49 return PTR_ERR(mdiodev->reset_gpio);
50
51 if (mdiodev->reset_gpio)
52 gpiod_set_consumer_name(mdiodev->reset_gpio, "PHY reset");
53
54 return 0;
55}
56
57static int mdiobus_register_reset(struct mdio_device *mdiodev)
58{
59 struct reset_control *reset;
60
61 reset = reset_control_get_optional_exclusive(&mdiodev->dev, "phy");
62 if (IS_ERR(reset))
63 return PTR_ERR(reset);
64
65 mdiodev->reset_ctrl = reset;
66
67 return 0;
68}
69
70int mdiobus_register_device(struct mdio_device *mdiodev)
71{
72 int err;
73
74 if (mdiodev->bus->mdio_map[mdiodev->addr])
75 return -EBUSY;
76
77 if (mdiodev->flags & MDIO_DEVICE_FLAG_PHY) {
78 err = mdiobus_register_gpiod(mdiodev);
79 if (err)
80 return err;
81
82 err = mdiobus_register_reset(mdiodev);
83 if (err)
84 return err;
85
86 /* Assert the reset signal */
87 mdio_device_reset(mdiodev, 1);
88 }
89
90 mdiodev->bus->mdio_map[mdiodev->addr] = mdiodev;
91
92 return 0;
93}
94EXPORT_SYMBOL(mdiobus_register_device);
95
96int mdiobus_unregister_device(struct mdio_device *mdiodev)
97{
98 if (mdiodev->bus->mdio_map[mdiodev->addr] != mdiodev)
99 return -EINVAL;
100
101 reset_control_put(mdiodev->reset_ctrl);
102
103 mdiodev->bus->mdio_map[mdiodev->addr] = NULL;
104
105 return 0;
106}
107EXPORT_SYMBOL(mdiobus_unregister_device);
108
109struct phy_device *mdiobus_get_phy(struct mii_bus *bus, int addr)
110{
111 struct mdio_device *mdiodev = bus->mdio_map[addr];
112
113 if (!mdiodev)
114 return NULL;
115
116 if (!(mdiodev->flags & MDIO_DEVICE_FLAG_PHY))
117 return NULL;
118
119 return container_of(mdiodev, struct phy_device, mdio);
120}
121EXPORT_SYMBOL(mdiobus_get_phy);
122
123bool mdiobus_is_registered_device(struct mii_bus *bus, int addr)
124{
125 return bus->mdio_map[addr];
126}
127EXPORT_SYMBOL(mdiobus_is_registered_device);
128
129/**
130 * mdiobus_alloc_size - allocate a mii_bus structure
131 * @size: extra amount of memory to allocate for private storage.
132 * If non-zero, then bus->priv is points to that memory.
133 *
134 * Description: called by a bus driver to allocate an mii_bus
135 * structure to fill in.
136 */
137struct mii_bus *mdiobus_alloc_size(size_t size)
138{
139 struct mii_bus *bus;
140 size_t aligned_size = ALIGN(sizeof(*bus), NETDEV_ALIGN);
141 size_t alloc_size;
142 int i;
143
144 /* If we alloc extra space, it should be aligned */
145 if (size)
146 alloc_size = aligned_size + size;
147 else
148 alloc_size = sizeof(*bus);
149
150 bus = kzalloc(alloc_size, GFP_KERNEL);
151 if (!bus)
152 return NULL;
153
154 bus->state = MDIOBUS_ALLOCATED;
155 if (size)
156 bus->priv = (void *)bus + aligned_size;
157
158 /* Initialise the interrupts to polling and 64-bit seqcounts */
159 for (i = 0; i < PHY_MAX_ADDR; i++) {
160 bus->irq[i] = PHY_POLL;
161 u64_stats_init(&bus->stats[i].syncp);
162 }
163
164 return bus;
165}
166EXPORT_SYMBOL(mdiobus_alloc_size);
167
168/**
169 * mdiobus_release - mii_bus device release callback
170 * @d: the target struct device that contains the mii_bus
171 *
172 * Description: called when the last reference to an mii_bus is
173 * dropped, to free the underlying memory.
174 */
175static void mdiobus_release(struct device *d)
176{
177 struct mii_bus *bus = to_mii_bus(d);
178
179 BUG_ON(bus->state != MDIOBUS_RELEASED &&
180 /* for compatibility with error handling in drivers */
181 bus->state != MDIOBUS_ALLOCATED);
182 kfree(bus);
183}
184
185struct mdio_bus_stat_attr {
186 int addr;
187 unsigned int field_offset;
188};
189
190static u64 mdio_bus_get_stat(struct mdio_bus_stats *s, unsigned int offset)
191{
192 const char *p = (const char *)s + offset;
193 unsigned int start;
194 u64 val = 0;
195
196 do {
197 start = u64_stats_fetch_begin(&s->syncp);
198 val = u64_stats_read((const u64_stats_t *)p);
199 } while (u64_stats_fetch_retry(&s->syncp, start));
200
201 return val;
202}
203
204static u64 mdio_bus_get_global_stat(struct mii_bus *bus, unsigned int offset)
205{
206 unsigned int i;
207 u64 val = 0;
208
209 for (i = 0; i < PHY_MAX_ADDR; i++)
210 val += mdio_bus_get_stat(&bus->stats[i], offset);
211
212 return val;
213}
214
215static ssize_t mdio_bus_stat_field_show(struct device *dev,
216 struct device_attribute *attr,
217 char *buf)
218{
219 struct mii_bus *bus = to_mii_bus(dev);
220 struct mdio_bus_stat_attr *sattr;
221 struct dev_ext_attribute *eattr;
222 u64 val;
223
224 eattr = container_of(attr, struct dev_ext_attribute, attr);
225 sattr = eattr->var;
226
227 if (sattr->addr < 0)
228 val = mdio_bus_get_global_stat(bus, sattr->field_offset);
229 else
230 val = mdio_bus_get_stat(&bus->stats[sattr->addr],
231 sattr->field_offset);
232
233 return sprintf(buf, "%llu\n", val);
234}
235
236static ssize_t mdio_bus_device_stat_field_show(struct device *dev,
237 struct device_attribute *attr,
238 char *buf)
239{
240 struct mdio_device *mdiodev = to_mdio_device(dev);
241 struct mii_bus *bus = mdiodev->bus;
242 struct mdio_bus_stat_attr *sattr;
243 struct dev_ext_attribute *eattr;
244 int addr = mdiodev->addr;
245 u64 val;
246
247 eattr = container_of(attr, struct dev_ext_attribute, attr);
248 sattr = eattr->var;
249
250 val = mdio_bus_get_stat(&bus->stats[addr], sattr->field_offset);
251
252 return sprintf(buf, "%llu\n", val);
253}
254
255#define MDIO_BUS_STATS_ATTR_DECL(field, file) \
256static struct dev_ext_attribute dev_attr_mdio_bus_##field = { \
257 .attr = { .attr = { .name = file, .mode = 0444 }, \
258 .show = mdio_bus_stat_field_show, \
259 }, \
260 .var = &((struct mdio_bus_stat_attr) { \
261 -1, offsetof(struct mdio_bus_stats, field) \
262 }), \
263}; \
264static struct dev_ext_attribute dev_attr_mdio_bus_device_##field = { \
265 .attr = { .attr = { .name = file, .mode = 0444 }, \
266 .show = mdio_bus_device_stat_field_show, \
267 }, \
268 .var = &((struct mdio_bus_stat_attr) { \
269 -1, offsetof(struct mdio_bus_stats, field) \
270 }), \
271};
272
273#define MDIO_BUS_STATS_ATTR(field) \
274 MDIO_BUS_STATS_ATTR_DECL(field, __stringify(field))
275
276MDIO_BUS_STATS_ATTR(transfers);
277MDIO_BUS_STATS_ATTR(errors);
278MDIO_BUS_STATS_ATTR(writes);
279MDIO_BUS_STATS_ATTR(reads);
280
281#define MDIO_BUS_STATS_ADDR_ATTR_DECL(field, addr, file) \
282static struct dev_ext_attribute dev_attr_mdio_bus_addr_##field##_##addr = { \
283 .attr = { .attr = { .name = file, .mode = 0444 }, \
284 .show = mdio_bus_stat_field_show, \
285 }, \
286 .var = &((struct mdio_bus_stat_attr) { \
287 addr, offsetof(struct mdio_bus_stats, field) \
288 }), \
289}
290
291#define MDIO_BUS_STATS_ADDR_ATTR(field, addr) \
292 MDIO_BUS_STATS_ADDR_ATTR_DECL(field, addr, \
293 __stringify(field) "_" __stringify(addr))
294
295#define MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(addr) \
296 MDIO_BUS_STATS_ADDR_ATTR(transfers, addr); \
297 MDIO_BUS_STATS_ADDR_ATTR(errors, addr); \
298 MDIO_BUS_STATS_ADDR_ATTR(writes, addr); \
299 MDIO_BUS_STATS_ADDR_ATTR(reads, addr) \
300
301MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(0);
302MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(1);
303MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(2);
304MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(3);
305MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(4);
306MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(5);
307MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(6);
308MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(7);
309MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(8);
310MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(9);
311MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(10);
312MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(11);
313MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(12);
314MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(13);
315MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(14);
316MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(15);
317MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(16);
318MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(17);
319MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(18);
320MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(19);
321MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(20);
322MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(21);
323MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(22);
324MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(23);
325MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(24);
326MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(25);
327MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(26);
328MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(27);
329MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(28);
330MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(29);
331MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(30);
332MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(31);
333
334#define MDIO_BUS_STATS_ADDR_ATTR_GROUP(addr) \
335 &dev_attr_mdio_bus_addr_transfers_##addr.attr.attr, \
336 &dev_attr_mdio_bus_addr_errors_##addr.attr.attr, \
337 &dev_attr_mdio_bus_addr_writes_##addr.attr.attr, \
338 &dev_attr_mdio_bus_addr_reads_##addr.attr.attr \
339
340static struct attribute *mdio_bus_statistics_attrs[] = {
341 &dev_attr_mdio_bus_transfers.attr.attr,
342 &dev_attr_mdio_bus_errors.attr.attr,
343 &dev_attr_mdio_bus_writes.attr.attr,
344 &dev_attr_mdio_bus_reads.attr.attr,
345 MDIO_BUS_STATS_ADDR_ATTR_GROUP(0),
346 MDIO_BUS_STATS_ADDR_ATTR_GROUP(1),
347 MDIO_BUS_STATS_ADDR_ATTR_GROUP(2),
348 MDIO_BUS_STATS_ADDR_ATTR_GROUP(3),
349 MDIO_BUS_STATS_ADDR_ATTR_GROUP(4),
350 MDIO_BUS_STATS_ADDR_ATTR_GROUP(5),
351 MDIO_BUS_STATS_ADDR_ATTR_GROUP(6),
352 MDIO_BUS_STATS_ADDR_ATTR_GROUP(7),
353 MDIO_BUS_STATS_ADDR_ATTR_GROUP(8),
354 MDIO_BUS_STATS_ADDR_ATTR_GROUP(9),
355 MDIO_BUS_STATS_ADDR_ATTR_GROUP(10),
356 MDIO_BUS_STATS_ADDR_ATTR_GROUP(11),
357 MDIO_BUS_STATS_ADDR_ATTR_GROUP(12),
358 MDIO_BUS_STATS_ADDR_ATTR_GROUP(13),
359 MDIO_BUS_STATS_ADDR_ATTR_GROUP(14),
360 MDIO_BUS_STATS_ADDR_ATTR_GROUP(15),
361 MDIO_BUS_STATS_ADDR_ATTR_GROUP(16),
362 MDIO_BUS_STATS_ADDR_ATTR_GROUP(17),
363 MDIO_BUS_STATS_ADDR_ATTR_GROUP(18),
364 MDIO_BUS_STATS_ADDR_ATTR_GROUP(19),
365 MDIO_BUS_STATS_ADDR_ATTR_GROUP(20),
366 MDIO_BUS_STATS_ADDR_ATTR_GROUP(21),
367 MDIO_BUS_STATS_ADDR_ATTR_GROUP(22),
368 MDIO_BUS_STATS_ADDR_ATTR_GROUP(23),
369 MDIO_BUS_STATS_ADDR_ATTR_GROUP(24),
370 MDIO_BUS_STATS_ADDR_ATTR_GROUP(25),
371 MDIO_BUS_STATS_ADDR_ATTR_GROUP(26),
372 MDIO_BUS_STATS_ADDR_ATTR_GROUP(27),
373 MDIO_BUS_STATS_ADDR_ATTR_GROUP(28),
374 MDIO_BUS_STATS_ADDR_ATTR_GROUP(29),
375 MDIO_BUS_STATS_ADDR_ATTR_GROUP(30),
376 MDIO_BUS_STATS_ADDR_ATTR_GROUP(31),
377 NULL,
378};
379
380static const struct attribute_group mdio_bus_statistics_group = {
381 .name = "statistics",
382 .attrs = mdio_bus_statistics_attrs,
383};
384
385static const struct attribute_group *mdio_bus_groups[] = {
386 &mdio_bus_statistics_group,
387 NULL,
388};
389
390static struct class mdio_bus_class = {
391 .name = "mdio_bus",
392 .dev_release = mdiobus_release,
393 .dev_groups = mdio_bus_groups,
394};
395
396/**
397 * mdio_find_bus - Given the name of a mdiobus, find the mii_bus.
398 * @mdio_name: The name of a mdiobus.
399 *
400 * Returns a reference to the mii_bus, or NULL if none found. The
401 * embedded struct device will have its reference count incremented,
402 * and this must be put_deviced'ed once the bus is finished with.
403 */
404struct mii_bus *mdio_find_bus(const char *mdio_name)
405{
406 struct device *d;
407
408 d = class_find_device_by_name(&mdio_bus_class, mdio_name);
409 return d ? to_mii_bus(d) : NULL;
410}
411EXPORT_SYMBOL(mdio_find_bus);
412
413#if IS_ENABLED(CONFIG_OF_MDIO)
414/**
415 * of_mdio_find_bus - Given an mii_bus node, find the mii_bus.
416 * @mdio_bus_np: Pointer to the mii_bus.
417 *
418 * Returns a reference to the mii_bus, or NULL if none found. The
419 * embedded struct device will have its reference count incremented,
420 * and this must be put once the bus is finished with.
421 *
422 * Because the association of a device_node and mii_bus is made via
423 * of_mdiobus_register(), the mii_bus cannot be found before it is
424 * registered with of_mdiobus_register().
425 *
426 */
427struct mii_bus *of_mdio_find_bus(struct device_node *mdio_bus_np)
428{
429 struct device *d;
430
431 if (!mdio_bus_np)
432 return NULL;
433
434 d = class_find_device_by_of_node(&mdio_bus_class, mdio_bus_np);
435 return d ? to_mii_bus(d) : NULL;
436}
437EXPORT_SYMBOL(of_mdio_find_bus);
438
439/* Walk the list of subnodes of a mdio bus and look for a node that
440 * matches the mdio device's address with its 'reg' property. If
441 * found, set the of_node pointer for the mdio device. This allows
442 * auto-probed phy devices to be supplied with information passed in
443 * via DT.
444 */
445static void of_mdiobus_link_mdiodev(struct mii_bus *bus,
446 struct mdio_device *mdiodev)
447{
448 struct device *dev = &mdiodev->dev;
449 struct device_node *child;
450
451 if (dev->of_node || !bus->dev.of_node)
452 return;
453
454 for_each_available_child_of_node(bus->dev.of_node, child) {
455 int addr;
456
457 addr = of_mdio_parse_addr(dev, child);
458 if (addr < 0)
459 continue;
460
461 if (addr == mdiodev->addr) {
462 device_set_node(dev, of_fwnode_handle(child));
463 return;
464 }
465 }
466}
467#else /* !IS_ENABLED(CONFIG_OF_MDIO) */
468static inline void of_mdiobus_link_mdiodev(struct mii_bus *mdio,
469 struct mdio_device *mdiodev)
470{
471}
472#endif
473
474/**
475 * mdiobus_create_device - create a full MDIO device given
476 * a mdio_board_info structure
477 * @bus: MDIO bus to create the devices on
478 * @bi: mdio_board_info structure describing the devices
479 *
480 * Returns 0 on success or < 0 on error.
481 */
482static int mdiobus_create_device(struct mii_bus *bus,
483 struct mdio_board_info *bi)
484{
485 struct mdio_device *mdiodev;
486 int ret = 0;
487
488 mdiodev = mdio_device_create(bus, bi->mdio_addr);
489 if (IS_ERR(mdiodev))
490 return -ENODEV;
491
492 strncpy(mdiodev->modalias, bi->modalias,
493 sizeof(mdiodev->modalias));
494 mdiodev->bus_match = mdio_device_bus_match;
495 mdiodev->dev.platform_data = (void *)bi->platform_data;
496
497 ret = mdio_device_register(mdiodev);
498 if (ret)
499 mdio_device_free(mdiodev);
500
501 return ret;
502}
503
504/**
505 * __mdiobus_register - bring up all the PHYs on a given bus and attach them to bus
506 * @bus: target mii_bus
507 * @owner: module containing bus accessor functions
508 *
509 * Description: Called by a bus driver to bring up all the PHYs
510 * on a given bus, and attach them to the bus. Drivers should use
511 * mdiobus_register() rather than __mdiobus_register() unless they
512 * need to pass a specific owner module. MDIO devices which are not
513 * PHYs will not be brought up by this function. They are expected
514 * to be explicitly listed in DT and instantiated by of_mdiobus_register().
515 *
516 * Returns 0 on success or < 0 on error.
517 */
518int __mdiobus_register(struct mii_bus *bus, struct module *owner)
519{
520 struct mdio_device *mdiodev;
521 int i, err;
522 struct gpio_desc *gpiod;
523
524 if (NULL == bus || NULL == bus->name ||
525 NULL == bus->read || NULL == bus->write)
526 return -EINVAL;
527
528 if (bus->parent && bus->parent->of_node)
529 bus->parent->of_node->fwnode.flags |=
530 FWNODE_FLAG_NEEDS_CHILD_BOUND_ON_ADD;
531
532 BUG_ON(bus->state != MDIOBUS_ALLOCATED &&
533 bus->state != MDIOBUS_UNREGISTERED);
534
535 bus->owner = owner;
536 bus->dev.parent = bus->parent;
537 bus->dev.class = &mdio_bus_class;
538 bus->dev.groups = NULL;
539 dev_set_name(&bus->dev, "%s", bus->id);
540
541 /* We need to set state to MDIOBUS_UNREGISTERED to correctly release
542 * the device in mdiobus_free()
543 *
544 * State will be updated later in this function in case of success
545 */
546 bus->state = MDIOBUS_UNREGISTERED;
547
548 err = device_register(&bus->dev);
549 if (err) {
550 pr_err("mii_bus %s failed to register\n", bus->id);
551 put_device(&bus->dev);
552 return -EINVAL;
553 }
554
555 mutex_init(&bus->mdio_lock);
556 mutex_init(&bus->shared_lock);
557
558 /* assert bus level PHY GPIO reset */
559 gpiod = devm_gpiod_get_optional(&bus->dev, "reset", GPIOD_OUT_HIGH);
560 if (IS_ERR(gpiod)) {
561 err = dev_err_probe(&bus->dev, PTR_ERR(gpiod),
562 "mii_bus %s couldn't get reset GPIO\n",
563 bus->id);
564 device_del(&bus->dev);
565 return err;
566 } else if (gpiod) {
567 bus->reset_gpiod = gpiod;
568 fsleep(bus->reset_delay_us);
569 gpiod_set_value_cansleep(gpiod, 0);
570 if (bus->reset_post_delay_us > 0)
571 fsleep(bus->reset_post_delay_us);
572 }
573
574 if (bus->reset) {
575 err = bus->reset(bus);
576 if (err)
577 goto error_reset_gpiod;
578 }
579
580 for (i = 0; i < PHY_MAX_ADDR; i++) {
581 if ((bus->phy_mask & (1 << i)) == 0) {
582 struct phy_device *phydev;
583
584 phydev = mdiobus_scan(bus, i);
585 if (IS_ERR(phydev) && (PTR_ERR(phydev) != -ENODEV)) {
586 err = PTR_ERR(phydev);
587 goto error;
588 }
589 }
590 }
591
592 mdiobus_setup_mdiodev_from_board_info(bus, mdiobus_create_device);
593
594 bus->state = MDIOBUS_REGISTERED;
595 pr_info("%s: probed\n", bus->name);
596 return 0;
597
598error:
599 while (--i >= 0) {
600 mdiodev = bus->mdio_map[i];
601 if (!mdiodev)
602 continue;
603
604 mdiodev->device_remove(mdiodev);
605 mdiodev->device_free(mdiodev);
606 }
607error_reset_gpiod:
608 /* Put PHYs in RESET to save power */
609 if (bus->reset_gpiod)
610 gpiod_set_value_cansleep(bus->reset_gpiod, 1);
611
612 device_del(&bus->dev);
613 return err;
614}
615EXPORT_SYMBOL(__mdiobus_register);
616
617void mdiobus_unregister(struct mii_bus *bus)
618{
619 struct mdio_device *mdiodev;
620 int i;
621
622 if (WARN_ON_ONCE(bus->state != MDIOBUS_REGISTERED))
623 return;
624 bus->state = MDIOBUS_UNREGISTERED;
625
626 for (i = 0; i < PHY_MAX_ADDR; i++) {
627 mdiodev = bus->mdio_map[i];
628 if (!mdiodev)
629 continue;
630
631 if (mdiodev->reset_gpio)
632 gpiod_put(mdiodev->reset_gpio);
633
634 mdiodev->device_remove(mdiodev);
635 mdiodev->device_free(mdiodev);
636 }
637
638 /* Put PHYs in RESET to save power */
639 if (bus->reset_gpiod)
640 gpiod_set_value_cansleep(bus->reset_gpiod, 1);
641
642 device_del(&bus->dev);
643}
644EXPORT_SYMBOL(mdiobus_unregister);
645
646/**
647 * mdiobus_free - free a struct mii_bus
648 * @bus: mii_bus to free
649 *
650 * This function releases the reference to the underlying device
651 * object in the mii_bus. If this is the last reference, the mii_bus
652 * will be freed.
653 */
654void mdiobus_free(struct mii_bus *bus)
655{
656 /* For compatibility with error handling in drivers. */
657 if (bus->state == MDIOBUS_ALLOCATED) {
658 kfree(bus);
659 return;
660 }
661
662 BUG_ON(bus->state != MDIOBUS_UNREGISTERED);
663 bus->state = MDIOBUS_RELEASED;
664
665 put_device(&bus->dev);
666}
667EXPORT_SYMBOL(mdiobus_free);
668
669/**
670 * mdiobus_scan - scan a bus for MDIO devices.
671 * @bus: mii_bus to scan
672 * @addr: address on bus to scan
673 *
674 * This function scans the MDIO bus, looking for devices which can be
675 * identified using a vendor/product ID in registers 2 and 3. Not all
676 * MDIO devices have such registers, but PHY devices typically
677 * do. Hence this function assumes anything found is a PHY, or can be
678 * treated as a PHY. Other MDIO devices, such as switches, will
679 * probably not be found during the scan.
680 */
681struct phy_device *mdiobus_scan(struct mii_bus *bus, int addr)
682{
683 struct phy_device *phydev = ERR_PTR(-ENODEV);
684 int err;
685
686 switch (bus->probe_capabilities) {
687 case MDIOBUS_NO_CAP:
688 case MDIOBUS_C22:
689 phydev = get_phy_device(bus, addr, false);
690 break;
691 case MDIOBUS_C45:
692 phydev = get_phy_device(bus, addr, true);
693 break;
694 case MDIOBUS_C22_C45:
695 phydev = get_phy_device(bus, addr, false);
696 if (IS_ERR(phydev))
697 phydev = get_phy_device(bus, addr, true);
698 break;
699 }
700
701 if (IS_ERR(phydev))
702 return phydev;
703
704 /*
705 * For DT, see if the auto-probed phy has a correspoding child
706 * in the bus node, and set the of_node pointer in this case.
707 */
708 of_mdiobus_link_mdiodev(bus, &phydev->mdio);
709
710 err = phy_device_register(phydev);
711 if (err) {
712 phy_device_free(phydev);
713 return ERR_PTR(-ENODEV);
714 }
715
716 return phydev;
717}
718EXPORT_SYMBOL(mdiobus_scan);
719
720static void mdiobus_stats_acct(struct mdio_bus_stats *stats, bool op, int ret)
721{
722 preempt_disable();
723 u64_stats_update_begin(&stats->syncp);
724
725 u64_stats_inc(&stats->transfers);
726 if (ret < 0) {
727 u64_stats_inc(&stats->errors);
728 goto out;
729 }
730
731 if (op)
732 u64_stats_inc(&stats->reads);
733 else
734 u64_stats_inc(&stats->writes);
735out:
736 u64_stats_update_end(&stats->syncp);
737 preempt_enable();
738}
739
740/**
741 * __mdiobus_read - Unlocked version of the mdiobus_read function
742 * @bus: the mii_bus struct
743 * @addr: the phy address
744 * @regnum: register number to read
745 *
746 * Read a MDIO bus register. Caller must hold the mdio bus lock.
747 *
748 * NOTE: MUST NOT be called from interrupt context.
749 */
750int __mdiobus_read(struct mii_bus *bus, int addr, u32 regnum)
751{
752 int retval;
753
754 lockdep_assert_held_once(&bus->mdio_lock);
755
756 retval = bus->read(bus, addr, regnum);
757
758 trace_mdio_access(bus, 1, addr, regnum, retval, retval);
759 mdiobus_stats_acct(&bus->stats[addr], true, retval);
760
761 return retval;
762}
763EXPORT_SYMBOL(__mdiobus_read);
764
765/**
766 * __mdiobus_write - Unlocked version of the mdiobus_write function
767 * @bus: the mii_bus struct
768 * @addr: the phy address
769 * @regnum: register number to write
770 * @val: value to write to @regnum
771 *
772 * Write a MDIO bus register. Caller must hold the mdio bus lock.
773 *
774 * NOTE: MUST NOT be called from interrupt context.
775 */
776int __mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val)
777{
778 int err;
779
780 lockdep_assert_held_once(&bus->mdio_lock);
781
782 err = bus->write(bus, addr, regnum, val);
783
784 trace_mdio_access(bus, 0, addr, regnum, val, err);
785 mdiobus_stats_acct(&bus->stats[addr], false, err);
786
787 return err;
788}
789EXPORT_SYMBOL(__mdiobus_write);
790
791/**
792 * __mdiobus_modify_changed - Unlocked version of the mdiobus_modify function
793 * @bus: the mii_bus struct
794 * @addr: the phy address
795 * @regnum: register number to modify
796 * @mask: bit mask of bits to clear
797 * @set: bit mask of bits to set
798 *
799 * Read, modify, and if any change, write the register value back to the
800 * device. Any error returns a negative number.
801 *
802 * NOTE: MUST NOT be called from interrupt context.
803 */
804int __mdiobus_modify_changed(struct mii_bus *bus, int addr, u32 regnum,
805 u16 mask, u16 set)
806{
807 int new, ret;
808
809 ret = __mdiobus_read(bus, addr, regnum);
810 if (ret < 0)
811 return ret;
812
813 new = (ret & ~mask) | set;
814 if (new == ret)
815 return 0;
816
817 ret = __mdiobus_write(bus, addr, regnum, new);
818
819 return ret < 0 ? ret : 1;
820}
821EXPORT_SYMBOL_GPL(__mdiobus_modify_changed);
822
823/**
824 * mdiobus_read_nested - Nested version of the mdiobus_read function
825 * @bus: the mii_bus struct
826 * @addr: the phy address
827 * @regnum: register number to read
828 *
829 * In case of nested MDIO bus access avoid lockdep false positives by
830 * using mutex_lock_nested().
831 *
832 * NOTE: MUST NOT be called from interrupt context,
833 * because the bus read/write functions may wait for an interrupt
834 * to conclude the operation.
835 */
836int mdiobus_read_nested(struct mii_bus *bus, int addr, u32 regnum)
837{
838 int retval;
839
840 mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED);
841 retval = __mdiobus_read(bus, addr, regnum);
842 mutex_unlock(&bus->mdio_lock);
843
844 return retval;
845}
846EXPORT_SYMBOL(mdiobus_read_nested);
847
848/**
849 * mdiobus_read - Convenience function for reading a given MII mgmt register
850 * @bus: the mii_bus struct
851 * @addr: the phy address
852 * @regnum: register number to read
853 *
854 * NOTE: MUST NOT be called from interrupt context,
855 * because the bus read/write functions may wait for an interrupt
856 * to conclude the operation.
857 */
858int mdiobus_read(struct mii_bus *bus, int addr, u32 regnum)
859{
860 int retval;
861
862 mutex_lock(&bus->mdio_lock);
863 retval = __mdiobus_read(bus, addr, regnum);
864 mutex_unlock(&bus->mdio_lock);
865
866 return retval;
867}
868EXPORT_SYMBOL(mdiobus_read);
869
870/**
871 * mdiobus_write_nested - Nested version of the mdiobus_write function
872 * @bus: the mii_bus struct
873 * @addr: the phy address
874 * @regnum: register number to write
875 * @val: value to write to @regnum
876 *
877 * In case of nested MDIO bus access avoid lockdep false positives by
878 * using mutex_lock_nested().
879 *
880 * NOTE: MUST NOT be called from interrupt context,
881 * because the bus read/write functions may wait for an interrupt
882 * to conclude the operation.
883 */
884int mdiobus_write_nested(struct mii_bus *bus, int addr, u32 regnum, u16 val)
885{
886 int err;
887
888 mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED);
889 err = __mdiobus_write(bus, addr, regnum, val);
890 mutex_unlock(&bus->mdio_lock);
891
892 return err;
893}
894EXPORT_SYMBOL(mdiobus_write_nested);
895
896/**
897 * mdiobus_write - Convenience function for writing a given MII mgmt register
898 * @bus: the mii_bus struct
899 * @addr: the phy address
900 * @regnum: register number to write
901 * @val: value to write to @regnum
902 *
903 * NOTE: MUST NOT be called from interrupt context,
904 * because the bus read/write functions may wait for an interrupt
905 * to conclude the operation.
906 */
907int mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val)
908{
909 int err;
910
911 mutex_lock(&bus->mdio_lock);
912 err = __mdiobus_write(bus, addr, regnum, val);
913 mutex_unlock(&bus->mdio_lock);
914
915 return err;
916}
917EXPORT_SYMBOL(mdiobus_write);
918
919/**
920 * mdiobus_modify - Convenience function for modifying a given mdio device
921 * register
922 * @bus: the mii_bus struct
923 * @addr: the phy address
924 * @regnum: register number to write
925 * @mask: bit mask of bits to clear
926 * @set: bit mask of bits to set
927 */
928int mdiobus_modify(struct mii_bus *bus, int addr, u32 regnum, u16 mask, u16 set)
929{
930 int err;
931
932 mutex_lock(&bus->mdio_lock);
933 err = __mdiobus_modify_changed(bus, addr, regnum, mask, set);
934 mutex_unlock(&bus->mdio_lock);
935
936 return err < 0 ? err : 0;
937}
938EXPORT_SYMBOL_GPL(mdiobus_modify);
939
940/**
941 * mdio_bus_match - determine if given MDIO driver supports the given
942 * MDIO device
943 * @dev: target MDIO device
944 * @drv: given MDIO driver
945 *
946 * Description: Given a MDIO device, and a MDIO driver, return 1 if
947 * the driver supports the device. Otherwise, return 0. This may
948 * require calling the devices own match function, since different classes
949 * of MDIO devices have different match criteria.
950 */
951static int mdio_bus_match(struct device *dev, struct device_driver *drv)
952{
953 struct mdio_device *mdio = to_mdio_device(dev);
954
955 if (of_driver_match_device(dev, drv))
956 return 1;
957
958 if (mdio->bus_match)
959 return mdio->bus_match(dev, drv);
960
961 return 0;
962}
963
964static int mdio_uevent(struct device *dev, struct kobj_uevent_env *env)
965{
966 int rc;
967
968 /* Some devices have extra OF data and an OF-style MODALIAS */
969 rc = of_device_uevent_modalias(dev, env);
970 if (rc != -ENODEV)
971 return rc;
972
973 return 0;
974}
975
976static struct attribute *mdio_bus_device_statistics_attrs[] = {
977 &dev_attr_mdio_bus_device_transfers.attr.attr,
978 &dev_attr_mdio_bus_device_errors.attr.attr,
979 &dev_attr_mdio_bus_device_writes.attr.attr,
980 &dev_attr_mdio_bus_device_reads.attr.attr,
981 NULL,
982};
983
984static const struct attribute_group mdio_bus_device_statistics_group = {
985 .name = "statistics",
986 .attrs = mdio_bus_device_statistics_attrs,
987};
988
989static const struct attribute_group *mdio_bus_dev_groups[] = {
990 &mdio_bus_device_statistics_group,
991 NULL,
992};
993
994struct bus_type mdio_bus_type = {
995 .name = "mdio_bus",
996 .dev_groups = mdio_bus_dev_groups,
997 .match = mdio_bus_match,
998 .uevent = mdio_uevent,
999};
1000EXPORT_SYMBOL(mdio_bus_type);
1001
1002int __init mdio_bus_init(void)
1003{
1004 int ret;
1005
1006 ret = class_register(&mdio_bus_class);
1007 if (!ret) {
1008 ret = bus_register(&mdio_bus_type);
1009 if (ret)
1010 class_unregister(&mdio_bus_class);
1011 }
1012
1013 return ret;
1014}
1015EXPORT_SYMBOL_GPL(mdio_bus_init);
1016
1017#if IS_ENABLED(CONFIG_PHYLIB)
1018void mdio_bus_exit(void)
1019{
1020 class_unregister(&mdio_bus_class);
1021 bus_unregister(&mdio_bus_type);
1022}
1023EXPORT_SYMBOL_GPL(mdio_bus_exit);
1024#else
1025module_init(mdio_bus_init);
1026/* no module_exit, intentional */
1027MODULE_LICENSE("GPL");
1028MODULE_DESCRIPTION("MDIO bus/device layer");
1029#endif