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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/* 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/gpio.h>
26#include <linux/gpio/consumer.h>
27#include <linux/of_device.h>
28#include <linux/of_mdio.h>
29#include <linux/of_gpio.h>
30#include <linux/netdevice.h>
31#include <linux/etherdevice.h>
32#include <linux/skbuff.h>
33#include <linux/spinlock.h>
34#include <linux/mm.h>
35#include <linux/module.h>
36#include <linux/mii.h>
37#include <linux/ethtool.h>
38#include <linux/phy.h>
39#include <linux/io.h>
40#include <linux/uaccess.h>
41#include <linux/gpio/consumer.h>
42
43#include <asm/irq.h>
44
45#define CREATE_TRACE_POINTS
46#include <trace/events/mdio.h>
47
48#include "mdio-boardinfo.h"
49
50static int mdiobus_register_gpiod(struct mdio_device *mdiodev)
51{
52 struct gpio_desc *gpiod = NULL;
53
54 /* Deassert the optional reset signal */
55 if (mdiodev->dev.of_node)
56 gpiod = fwnode_get_named_gpiod(&mdiodev->dev.of_node->fwnode,
57 "reset-gpios", 0, GPIOD_OUT_LOW,
58 "PHY reset");
59 if (PTR_ERR(gpiod) == -ENOENT ||
60 PTR_ERR(gpiod) == -ENOSYS)
61 gpiod = NULL;
62 else if (IS_ERR(gpiod))
63 return PTR_ERR(gpiod);
64
65 mdiodev->reset = gpiod;
66
67 /* Assert the reset signal again */
68 mdio_device_reset(mdiodev, 1);
69
70 return 0;
71}
72
73int mdiobus_register_device(struct mdio_device *mdiodev)
74{
75 int err;
76
77 if (mdiodev->bus->mdio_map[mdiodev->addr])
78 return -EBUSY;
79
80 if (mdiodev->flags & MDIO_DEVICE_FLAG_PHY) {
81 err = mdiobus_register_gpiod(mdiodev);
82 if (err)
83 return err;
84 }
85
86 mdiodev->bus->mdio_map[mdiodev->addr] = mdiodev;
87
88 return 0;
89}
90EXPORT_SYMBOL(mdiobus_register_device);
91
92int mdiobus_unregister_device(struct mdio_device *mdiodev)
93{
94 if (mdiodev->bus->mdio_map[mdiodev->addr] != mdiodev)
95 return -EINVAL;
96
97 mdiodev->bus->mdio_map[mdiodev->addr] = NULL;
98
99 return 0;
100}
101EXPORT_SYMBOL(mdiobus_unregister_device);
102
103struct phy_device *mdiobus_get_phy(struct mii_bus *bus, int addr)
104{
105 struct mdio_device *mdiodev = bus->mdio_map[addr];
106
107 if (!mdiodev)
108 return NULL;
109
110 if (!(mdiodev->flags & MDIO_DEVICE_FLAG_PHY))
111 return NULL;
112
113 return container_of(mdiodev, struct phy_device, mdio);
114}
115EXPORT_SYMBOL(mdiobus_get_phy);
116
117bool mdiobus_is_registered_device(struct mii_bus *bus, int addr)
118{
119 return bus->mdio_map[addr];
120}
121EXPORT_SYMBOL(mdiobus_is_registered_device);
122
123/**
124 * mdiobus_alloc_size - allocate a mii_bus structure
125 * @size: extra amount of memory to allocate for private storage.
126 * If non-zero, then bus->priv is points to that memory.
127 *
128 * Description: called by a bus driver to allocate an mii_bus
129 * structure to fill in.
130 */
131struct mii_bus *mdiobus_alloc_size(size_t size)
132{
133 struct mii_bus *bus;
134 size_t aligned_size = ALIGN(sizeof(*bus), NETDEV_ALIGN);
135 size_t alloc_size;
136 int i;
137
138 /* If we alloc extra space, it should be aligned */
139 if (size)
140 alloc_size = aligned_size + size;
141 else
142 alloc_size = sizeof(*bus);
143
144 bus = kzalloc(alloc_size, GFP_KERNEL);
145 if (!bus)
146 return NULL;
147
148 bus->state = MDIOBUS_ALLOCATED;
149 if (size)
150 bus->priv = (void *)bus + aligned_size;
151
152 /* Initialise the interrupts to polling */
153 for (i = 0; i < PHY_MAX_ADDR; i++)
154 bus->irq[i] = PHY_POLL;
155
156 return bus;
157}
158EXPORT_SYMBOL(mdiobus_alloc_size);
159
160static void _devm_mdiobus_free(struct device *dev, void *res)
161{
162 mdiobus_free(*(struct mii_bus **)res);
163}
164
165static int devm_mdiobus_match(struct device *dev, void *res, void *data)
166{
167 struct mii_bus **r = res;
168
169 if (WARN_ON(!r || !*r))
170 return 0;
171
172 return *r == data;
173}
174
175/**
176 * devm_mdiobus_alloc_size - Resource-managed mdiobus_alloc_size()
177 * @dev: Device to allocate mii_bus for
178 * @sizeof_priv: Space to allocate for private structure.
179 *
180 * Managed mdiobus_alloc_size. mii_bus allocated with this function is
181 * automatically freed on driver detach.
182 *
183 * If an mii_bus allocated with this function needs to be freed separately,
184 * devm_mdiobus_free() must be used.
185 *
186 * RETURNS:
187 * Pointer to allocated mii_bus on success, NULL on failure.
188 */
189struct mii_bus *devm_mdiobus_alloc_size(struct device *dev, int sizeof_priv)
190{
191 struct mii_bus **ptr, *bus;
192
193 ptr = devres_alloc(_devm_mdiobus_free, sizeof(*ptr), GFP_KERNEL);
194 if (!ptr)
195 return NULL;
196
197 /* use raw alloc_dr for kmalloc caller tracing */
198 bus = mdiobus_alloc_size(sizeof_priv);
199 if (bus) {
200 *ptr = bus;
201 devres_add(dev, ptr);
202 } else {
203 devres_free(ptr);
204 }
205
206 return bus;
207}
208EXPORT_SYMBOL_GPL(devm_mdiobus_alloc_size);
209
210/**
211 * devm_mdiobus_free - Resource-managed mdiobus_free()
212 * @dev: Device this mii_bus belongs to
213 * @bus: the mii_bus associated with the device
214 *
215 * Free mii_bus allocated with devm_mdiobus_alloc_size().
216 */
217void devm_mdiobus_free(struct device *dev, struct mii_bus *bus)
218{
219 int rc;
220
221 rc = devres_release(dev, _devm_mdiobus_free,
222 devm_mdiobus_match, bus);
223 WARN_ON(rc);
224}
225EXPORT_SYMBOL_GPL(devm_mdiobus_free);
226
227/**
228 * mdiobus_release - mii_bus device release callback
229 * @d: the target struct device that contains the mii_bus
230 *
231 * Description: called when the last reference to an mii_bus is
232 * dropped, to free the underlying memory.
233 */
234static void mdiobus_release(struct device *d)
235{
236 struct mii_bus *bus = to_mii_bus(d);
237 BUG_ON(bus->state != MDIOBUS_RELEASED &&
238 /* for compatibility with error handling in drivers */
239 bus->state != MDIOBUS_ALLOCATED);
240 kfree(bus);
241}
242
243static struct class mdio_bus_class = {
244 .name = "mdio_bus",
245 .dev_release = mdiobus_release,
246};
247
248#if IS_ENABLED(CONFIG_OF_MDIO)
249/* Helper function for of_mdio_find_bus */
250static int of_mdio_bus_match(struct device *dev, const void *mdio_bus_np)
251{
252 return dev->of_node == mdio_bus_np;
253}
254/**
255 * of_mdio_find_bus - Given an mii_bus node, find the mii_bus.
256 * @mdio_bus_np: Pointer to the mii_bus.
257 *
258 * Returns a reference to the mii_bus, or NULL if none found. The
259 * embedded struct device will have its reference count incremented,
260 * and this must be put once the bus is finished with.
261 *
262 * Because the association of a device_node and mii_bus is made via
263 * of_mdiobus_register(), the mii_bus cannot be found before it is
264 * registered with of_mdiobus_register().
265 *
266 */
267struct mii_bus *of_mdio_find_bus(struct device_node *mdio_bus_np)
268{
269 struct device *d;
270
271 if (!mdio_bus_np)
272 return NULL;
273
274 d = class_find_device(&mdio_bus_class, NULL, mdio_bus_np,
275 of_mdio_bus_match);
276
277 return d ? to_mii_bus(d) : NULL;
278}
279EXPORT_SYMBOL(of_mdio_find_bus);
280
281/* Walk the list of subnodes of a mdio bus and look for a node that
282 * matches the mdio device's address with its 'reg' property. If
283 * found, set the of_node pointer for the mdio device. This allows
284 * auto-probed phy devices to be supplied with information passed in
285 * via DT.
286 */
287static void of_mdiobus_link_mdiodev(struct mii_bus *bus,
288 struct mdio_device *mdiodev)
289{
290 struct device *dev = &mdiodev->dev;
291 struct device_node *child;
292
293 if (dev->of_node || !bus->dev.of_node)
294 return;
295
296 for_each_available_child_of_node(bus->dev.of_node, child) {
297 int addr;
298
299 addr = of_mdio_parse_addr(dev, child);
300 if (addr < 0)
301 continue;
302
303 if (addr == mdiodev->addr) {
304 dev->of_node = child;
305 dev->fwnode = of_fwnode_handle(child);
306 return;
307 }
308 }
309}
310#else /* !IS_ENABLED(CONFIG_OF_MDIO) */
311static inline void of_mdiobus_link_mdiodev(struct mii_bus *mdio,
312 struct mdio_device *mdiodev)
313{
314}
315#endif
316
317/**
318 * mdiobus_create_device_from_board_info - create a full MDIO device given
319 * a mdio_board_info structure
320 * @bus: MDIO bus to create the devices on
321 * @bi: mdio_board_info structure describing the devices
322 *
323 * Returns 0 on success or < 0 on error.
324 */
325static int mdiobus_create_device(struct mii_bus *bus,
326 struct mdio_board_info *bi)
327{
328 struct mdio_device *mdiodev;
329 int ret = 0;
330
331 mdiodev = mdio_device_create(bus, bi->mdio_addr);
332 if (IS_ERR(mdiodev))
333 return -ENODEV;
334
335 strncpy(mdiodev->modalias, bi->modalias,
336 sizeof(mdiodev->modalias));
337 mdiodev->bus_match = mdio_device_bus_match;
338 mdiodev->dev.platform_data = (void *)bi->platform_data;
339
340 ret = mdio_device_register(mdiodev);
341 if (ret)
342 mdio_device_free(mdiodev);
343
344 return ret;
345}
346
347/**
348 * __mdiobus_register - bring up all the PHYs on a given bus and attach them to bus
349 * @bus: target mii_bus
350 * @owner: module containing bus accessor functions
351 *
352 * Description: Called by a bus driver to bring up all the PHYs
353 * on a given bus, and attach them to the bus. Drivers should use
354 * mdiobus_register() rather than __mdiobus_register() unless they
355 * need to pass a specific owner module. MDIO devices which are not
356 * PHYs will not be brought up by this function. They are expected to
357 * to be explicitly listed in DT and instantiated by of_mdiobus_register().
358 *
359 * Returns 0 on success or < 0 on error.
360 */
361int __mdiobus_register(struct mii_bus *bus, struct module *owner)
362{
363 struct mdio_device *mdiodev;
364 int i, err;
365 struct gpio_desc *gpiod;
366
367 if (NULL == bus || NULL == bus->name ||
368 NULL == bus->read || NULL == bus->write)
369 return -EINVAL;
370
371 BUG_ON(bus->state != MDIOBUS_ALLOCATED &&
372 bus->state != MDIOBUS_UNREGISTERED);
373
374 bus->owner = owner;
375 bus->dev.parent = bus->parent;
376 bus->dev.class = &mdio_bus_class;
377 bus->dev.groups = NULL;
378 dev_set_name(&bus->dev, "%s", bus->id);
379
380 err = device_register(&bus->dev);
381 if (err) {
382 pr_err("mii_bus %s failed to register\n", bus->id);
383 put_device(&bus->dev);
384 return -EINVAL;
385 }
386
387 mutex_init(&bus->mdio_lock);
388
389 /* de-assert bus level PHY GPIO reset */
390 gpiod = devm_gpiod_get_optional(&bus->dev, "reset", GPIOD_OUT_LOW);
391 if (IS_ERR(gpiod)) {
392 dev_err(&bus->dev, "mii_bus %s couldn't get reset GPIO\n",
393 bus->id);
394 return PTR_ERR(gpiod);
395 } else if (gpiod) {
396 bus->reset_gpiod = gpiod;
397
398 gpiod_set_value_cansleep(gpiod, 1);
399 udelay(bus->reset_delay_us);
400 gpiod_set_value_cansleep(gpiod, 0);
401 }
402
403 if (bus->reset)
404 bus->reset(bus);
405
406 for (i = 0; i < PHY_MAX_ADDR; i++) {
407 if ((bus->phy_mask & (1 << i)) == 0) {
408 struct phy_device *phydev;
409
410 phydev = mdiobus_scan(bus, i);
411 if (IS_ERR(phydev) && (PTR_ERR(phydev) != -ENODEV)) {
412 err = PTR_ERR(phydev);
413 goto error;
414 }
415 }
416 }
417
418 mdiobus_setup_mdiodev_from_board_info(bus, mdiobus_create_device);
419
420 bus->state = MDIOBUS_REGISTERED;
421 pr_info("%s: probed\n", bus->name);
422 return 0;
423
424error:
425 while (--i >= 0) {
426 mdiodev = bus->mdio_map[i];
427 if (!mdiodev)
428 continue;
429
430 mdiodev->device_remove(mdiodev);
431 mdiodev->device_free(mdiodev);
432 }
433
434 /* Put PHYs in RESET to save power */
435 if (bus->reset_gpiod)
436 gpiod_set_value_cansleep(bus->reset_gpiod, 1);
437
438 device_del(&bus->dev);
439 return err;
440}
441EXPORT_SYMBOL(__mdiobus_register);
442
443void mdiobus_unregister(struct mii_bus *bus)
444{
445 struct mdio_device *mdiodev;
446 int i;
447
448 BUG_ON(bus->state != MDIOBUS_REGISTERED);
449 bus->state = MDIOBUS_UNREGISTERED;
450
451 for (i = 0; i < PHY_MAX_ADDR; i++) {
452 mdiodev = bus->mdio_map[i];
453 if (!mdiodev)
454 continue;
455
456 if (mdiodev->reset)
457 gpiod_put(mdiodev->reset);
458
459 mdiodev->device_remove(mdiodev);
460 mdiodev->device_free(mdiodev);
461 }
462
463 /* Put PHYs in RESET to save power */
464 if (bus->reset_gpiod)
465 gpiod_set_value_cansleep(bus->reset_gpiod, 1);
466
467 device_del(&bus->dev);
468}
469EXPORT_SYMBOL(mdiobus_unregister);
470
471/**
472 * mdiobus_free - free a struct mii_bus
473 * @bus: mii_bus to free
474 *
475 * This function releases the reference to the underlying device
476 * object in the mii_bus. If this is the last reference, the mii_bus
477 * will be freed.
478 */
479void mdiobus_free(struct mii_bus *bus)
480{
481 /* For compatibility with error handling in drivers. */
482 if (bus->state == MDIOBUS_ALLOCATED) {
483 kfree(bus);
484 return;
485 }
486
487 BUG_ON(bus->state != MDIOBUS_UNREGISTERED);
488 bus->state = MDIOBUS_RELEASED;
489
490 put_device(&bus->dev);
491}
492EXPORT_SYMBOL(mdiobus_free);
493
494/**
495 * mdiobus_scan - scan a bus for MDIO devices.
496 * @bus: mii_bus to scan
497 * @addr: address on bus to scan
498 *
499 * This function scans the MDIO bus, looking for devices which can be
500 * identified using a vendor/product ID in registers 2 and 3. Not all
501 * MDIO devices have such registers, but PHY devices typically
502 * do. Hence this function assumes anything found is a PHY, or can be
503 * treated as a PHY. Other MDIO devices, such as switches, will
504 * probably not be found during the scan.
505 */
506struct phy_device *mdiobus_scan(struct mii_bus *bus, int addr)
507{
508 struct phy_device *phydev;
509 int err;
510
511 phydev = get_phy_device(bus, addr, false);
512 if (IS_ERR(phydev))
513 return phydev;
514
515 /*
516 * For DT, see if the auto-probed phy has a correspoding child
517 * in the bus node, and set the of_node pointer in this case.
518 */
519 of_mdiobus_link_mdiodev(bus, &phydev->mdio);
520
521 err = phy_device_register(phydev);
522 if (err) {
523 phy_device_free(phydev);
524 return ERR_PTR(-ENODEV);
525 }
526
527 return phydev;
528}
529EXPORT_SYMBOL(mdiobus_scan);
530
531/**
532 * __mdiobus_read - Unlocked version of the mdiobus_read function
533 * @bus: the mii_bus struct
534 * @addr: the phy address
535 * @regnum: register number to read
536 *
537 * Read a MDIO bus register. Caller must hold the mdio bus lock.
538 *
539 * NOTE: MUST NOT be called from interrupt context.
540 */
541int __mdiobus_read(struct mii_bus *bus, int addr, u32 regnum)
542{
543 int retval;
544
545 WARN_ON_ONCE(!mutex_is_locked(&bus->mdio_lock));
546
547 retval = bus->read(bus, addr, regnum);
548
549 trace_mdio_access(bus, 1, addr, regnum, retval, retval);
550
551 return retval;
552}
553EXPORT_SYMBOL(__mdiobus_read);
554
555/**
556 * __mdiobus_write - Unlocked version of the mdiobus_write function
557 * @bus: the mii_bus struct
558 * @addr: the phy address
559 * @regnum: register number to write
560 * @val: value to write to @regnum
561 *
562 * Write a MDIO bus register. Caller must hold the mdio bus lock.
563 *
564 * NOTE: MUST NOT be called from interrupt context.
565 */
566int __mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val)
567{
568 int err;
569
570 WARN_ON_ONCE(!mutex_is_locked(&bus->mdio_lock));
571
572 err = bus->write(bus, addr, regnum, val);
573
574 trace_mdio_access(bus, 0, addr, regnum, val, err);
575
576 return err;
577}
578EXPORT_SYMBOL(__mdiobus_write);
579
580/**
581 * mdiobus_read_nested - Nested version of the mdiobus_read function
582 * @bus: the mii_bus struct
583 * @addr: the phy address
584 * @regnum: register number to read
585 *
586 * In case of nested MDIO bus access avoid lockdep false positives by
587 * using mutex_lock_nested().
588 *
589 * NOTE: MUST NOT be called from interrupt context,
590 * because the bus read/write functions may wait for an interrupt
591 * to conclude the operation.
592 */
593int mdiobus_read_nested(struct mii_bus *bus, int addr, u32 regnum)
594{
595 int retval;
596
597 BUG_ON(in_interrupt());
598
599 mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED);
600 retval = __mdiobus_read(bus, addr, regnum);
601 mutex_unlock(&bus->mdio_lock);
602
603 return retval;
604}
605EXPORT_SYMBOL(mdiobus_read_nested);
606
607/**
608 * mdiobus_read - Convenience function for reading a given MII mgmt register
609 * @bus: the mii_bus struct
610 * @addr: the phy address
611 * @regnum: register number to read
612 *
613 * NOTE: MUST NOT be called from interrupt context,
614 * because the bus read/write functions may wait for an interrupt
615 * to conclude the operation.
616 */
617int mdiobus_read(struct mii_bus *bus, int addr, u32 regnum)
618{
619 int retval;
620
621 BUG_ON(in_interrupt());
622
623 mutex_lock(&bus->mdio_lock);
624 retval = __mdiobus_read(bus, addr, regnum);
625 mutex_unlock(&bus->mdio_lock);
626
627 return retval;
628}
629EXPORT_SYMBOL(mdiobus_read);
630
631/**
632 * mdiobus_write_nested - Nested version of the mdiobus_write function
633 * @bus: the mii_bus struct
634 * @addr: the phy address
635 * @regnum: register number to write
636 * @val: value to write to @regnum
637 *
638 * In case of nested MDIO bus access avoid lockdep false positives by
639 * using mutex_lock_nested().
640 *
641 * NOTE: MUST NOT be called from interrupt context,
642 * because the bus read/write functions may wait for an interrupt
643 * to conclude the operation.
644 */
645int mdiobus_write_nested(struct mii_bus *bus, int addr, u32 regnum, u16 val)
646{
647 int err;
648
649 BUG_ON(in_interrupt());
650
651 mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED);
652 err = __mdiobus_write(bus, addr, regnum, val);
653 mutex_unlock(&bus->mdio_lock);
654
655 return err;
656}
657EXPORT_SYMBOL(mdiobus_write_nested);
658
659/**
660 * mdiobus_write - Convenience function for writing a given MII mgmt register
661 * @bus: the mii_bus struct
662 * @addr: the phy address
663 * @regnum: register number to write
664 * @val: value to write to @regnum
665 *
666 * NOTE: MUST NOT be called from interrupt context,
667 * because the bus read/write functions may wait for an interrupt
668 * to conclude the operation.
669 */
670int mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val)
671{
672 int err;
673
674 BUG_ON(in_interrupt());
675
676 mutex_lock(&bus->mdio_lock);
677 err = __mdiobus_write(bus, addr, regnum, val);
678 mutex_unlock(&bus->mdio_lock);
679
680 return err;
681}
682EXPORT_SYMBOL(mdiobus_write);
683
684/**
685 * mdio_bus_match - determine if given MDIO driver supports the given
686 * MDIO device
687 * @dev: target MDIO device
688 * @drv: given MDIO driver
689 *
690 * Description: Given a MDIO device, and a MDIO driver, return 1 if
691 * the driver supports the device. Otherwise, return 0. This may
692 * require calling the devices own match function, since different classes
693 * of MDIO devices have different match criteria.
694 */
695static int mdio_bus_match(struct device *dev, struct device_driver *drv)
696{
697 struct mdio_device *mdio = to_mdio_device(dev);
698
699 if (of_driver_match_device(dev, drv))
700 return 1;
701
702 if (mdio->bus_match)
703 return mdio->bus_match(dev, drv);
704
705 return 0;
706}
707
708static int mdio_uevent(struct device *dev, struct kobj_uevent_env *env)
709{
710 int rc;
711
712 /* Some devices have extra OF data and an OF-style MODALIAS */
713 rc = of_device_uevent_modalias(dev, env);
714 if (rc != -ENODEV)
715 return rc;
716
717 return 0;
718}
719
720#ifdef CONFIG_PM
721static int mdio_bus_suspend(struct device *dev)
722{
723 struct mdio_device *mdio = to_mdio_device(dev);
724
725 if (mdio->pm_ops && mdio->pm_ops->suspend)
726 return mdio->pm_ops->suspend(dev);
727
728 return 0;
729}
730
731static int mdio_bus_resume(struct device *dev)
732{
733 struct mdio_device *mdio = to_mdio_device(dev);
734
735 if (mdio->pm_ops && mdio->pm_ops->resume)
736 return mdio->pm_ops->resume(dev);
737
738 return 0;
739}
740
741static int mdio_bus_restore(struct device *dev)
742{
743 struct mdio_device *mdio = to_mdio_device(dev);
744
745 if (mdio->pm_ops && mdio->pm_ops->restore)
746 return mdio->pm_ops->restore(dev);
747
748 return 0;
749}
750
751static const struct dev_pm_ops mdio_bus_pm_ops = {
752 .suspend = mdio_bus_suspend,
753 .resume = mdio_bus_resume,
754 .freeze = mdio_bus_suspend,
755 .thaw = mdio_bus_resume,
756 .restore = mdio_bus_restore,
757};
758
759#define MDIO_BUS_PM_OPS (&mdio_bus_pm_ops)
760
761#else
762
763#define MDIO_BUS_PM_OPS NULL
764
765#endif /* CONFIG_PM */
766
767struct bus_type mdio_bus_type = {
768 .name = "mdio_bus",
769 .match = mdio_bus_match,
770 .uevent = mdio_uevent,
771 .pm = MDIO_BUS_PM_OPS,
772};
773EXPORT_SYMBOL(mdio_bus_type);
774
775int __init mdio_bus_init(void)
776{
777 int ret;
778
779 ret = class_register(&mdio_bus_class);
780 if (!ret) {
781 ret = bus_register(&mdio_bus_type);
782 if (ret)
783 class_unregister(&mdio_bus_class);
784 }
785
786 return ret;
787}
788EXPORT_SYMBOL_GPL(mdio_bus_init);
789
790#if IS_ENABLED(CONFIG_PHYLIB)
791void mdio_bus_exit(void)
792{
793 class_unregister(&mdio_bus_class);
794 bus_unregister(&mdio_bus_type);
795}
796EXPORT_SYMBOL_GPL(mdio_bus_exit);
797#else
798module_init(mdio_bus_init);
799/* no module_exit, intentional */
800MODULE_LICENSE("GPL");
801MODULE_DESCRIPTION("MDIO bus/device layer");
802#endif