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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 BUG_ON(bus->state != MDIOBUS_RELEASED &&
179 /* for compatibility with error handling in drivers */
180 bus->state != MDIOBUS_ALLOCATED);
181 kfree(bus);
182}
183
184struct mdio_bus_stat_attr {
185 int addr;
186 unsigned int field_offset;
187};
188
189static u64 mdio_bus_get_stat(struct mdio_bus_stats *s, unsigned int offset)
190{
191 const char *p = (const char *)s + offset;
192 unsigned int start;
193 u64 val = 0;
194
195 do {
196 start = u64_stats_fetch_begin(&s->syncp);
197 val = u64_stats_read((const u64_stats_t *)p);
198 } while (u64_stats_fetch_retry(&s->syncp, start));
199
200 return val;
201}
202
203static u64 mdio_bus_get_global_stat(struct mii_bus *bus, unsigned int offset)
204{
205 unsigned int i;
206 u64 val = 0;
207
208 for (i = 0; i < PHY_MAX_ADDR; i++)
209 val += mdio_bus_get_stat(&bus->stats[i], offset);
210
211 return val;
212}
213
214static ssize_t mdio_bus_stat_field_show(struct device *dev,
215 struct device_attribute *attr,
216 char *buf)
217{
218 struct mii_bus *bus = to_mii_bus(dev);
219 struct mdio_bus_stat_attr *sattr;
220 struct dev_ext_attribute *eattr;
221 u64 val;
222
223 eattr = container_of(attr, struct dev_ext_attribute, attr);
224 sattr = eattr->var;
225
226 if (sattr->addr < 0)
227 val = mdio_bus_get_global_stat(bus, sattr->field_offset);
228 else
229 val = mdio_bus_get_stat(&bus->stats[sattr->addr],
230 sattr->field_offset);
231
232 return sprintf(buf, "%llu\n", val);
233}
234
235static ssize_t mdio_bus_device_stat_field_show(struct device *dev,
236 struct device_attribute *attr,
237 char *buf)
238{
239 struct mdio_device *mdiodev = to_mdio_device(dev);
240 struct mii_bus *bus = mdiodev->bus;
241 struct mdio_bus_stat_attr *sattr;
242 struct dev_ext_attribute *eattr;
243 int addr = mdiodev->addr;
244 u64 val;
245
246 eattr = container_of(attr, struct dev_ext_attribute, attr);
247 sattr = eattr->var;
248
249 val = mdio_bus_get_stat(&bus->stats[addr], sattr->field_offset);
250
251 return sprintf(buf, "%llu\n", val);
252}
253
254#define MDIO_BUS_STATS_ATTR_DECL(field, file) \
255static struct dev_ext_attribute dev_attr_mdio_bus_##field = { \
256 .attr = { .attr = { .name = file, .mode = 0444 }, \
257 .show = mdio_bus_stat_field_show, \
258 }, \
259 .var = &((struct mdio_bus_stat_attr) { \
260 -1, offsetof(struct mdio_bus_stats, field) \
261 }), \
262}; \
263static struct dev_ext_attribute dev_attr_mdio_bus_device_##field = { \
264 .attr = { .attr = { .name = file, .mode = 0444 }, \
265 .show = mdio_bus_device_stat_field_show, \
266 }, \
267 .var = &((struct mdio_bus_stat_attr) { \
268 -1, offsetof(struct mdio_bus_stats, field) \
269 }), \
270};
271
272#define MDIO_BUS_STATS_ATTR(field) \
273 MDIO_BUS_STATS_ATTR_DECL(field, __stringify(field))
274
275MDIO_BUS_STATS_ATTR(transfers);
276MDIO_BUS_STATS_ATTR(errors);
277MDIO_BUS_STATS_ATTR(writes);
278MDIO_BUS_STATS_ATTR(reads);
279
280#define MDIO_BUS_STATS_ADDR_ATTR_DECL(field, addr, file) \
281static struct dev_ext_attribute dev_attr_mdio_bus_addr_##field##_##addr = { \
282 .attr = { .attr = { .name = file, .mode = 0444 }, \
283 .show = mdio_bus_stat_field_show, \
284 }, \
285 .var = &((struct mdio_bus_stat_attr) { \
286 addr, offsetof(struct mdio_bus_stats, field) \
287 }), \
288}
289
290#define MDIO_BUS_STATS_ADDR_ATTR(field, addr) \
291 MDIO_BUS_STATS_ADDR_ATTR_DECL(field, addr, \
292 __stringify(field) "_" __stringify(addr))
293
294#define MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(addr) \
295 MDIO_BUS_STATS_ADDR_ATTR(transfers, addr); \
296 MDIO_BUS_STATS_ADDR_ATTR(errors, addr); \
297 MDIO_BUS_STATS_ADDR_ATTR(writes, addr); \
298 MDIO_BUS_STATS_ADDR_ATTR(reads, addr) \
299
300MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(0);
301MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(1);
302MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(2);
303MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(3);
304MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(4);
305MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(5);
306MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(6);
307MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(7);
308MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(8);
309MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(9);
310MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(10);
311MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(11);
312MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(12);
313MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(13);
314MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(14);
315MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(15);
316MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(16);
317MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(17);
318MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(18);
319MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(19);
320MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(20);
321MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(21);
322MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(22);
323MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(23);
324MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(24);
325MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(25);
326MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(26);
327MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(27);
328MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(28);
329MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(29);
330MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(30);
331MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(31);
332
333#define MDIO_BUS_STATS_ADDR_ATTR_GROUP(addr) \
334 &dev_attr_mdio_bus_addr_transfers_##addr.attr.attr, \
335 &dev_attr_mdio_bus_addr_errors_##addr.attr.attr, \
336 &dev_attr_mdio_bus_addr_writes_##addr.attr.attr, \
337 &dev_attr_mdio_bus_addr_reads_##addr.attr.attr \
338
339static struct attribute *mdio_bus_statistics_attrs[] = {
340 &dev_attr_mdio_bus_transfers.attr.attr,
341 &dev_attr_mdio_bus_errors.attr.attr,
342 &dev_attr_mdio_bus_writes.attr.attr,
343 &dev_attr_mdio_bus_reads.attr.attr,
344 MDIO_BUS_STATS_ADDR_ATTR_GROUP(0),
345 MDIO_BUS_STATS_ADDR_ATTR_GROUP(1),
346 MDIO_BUS_STATS_ADDR_ATTR_GROUP(2),
347 MDIO_BUS_STATS_ADDR_ATTR_GROUP(3),
348 MDIO_BUS_STATS_ADDR_ATTR_GROUP(4),
349 MDIO_BUS_STATS_ADDR_ATTR_GROUP(5),
350 MDIO_BUS_STATS_ADDR_ATTR_GROUP(6),
351 MDIO_BUS_STATS_ADDR_ATTR_GROUP(7),
352 MDIO_BUS_STATS_ADDR_ATTR_GROUP(8),
353 MDIO_BUS_STATS_ADDR_ATTR_GROUP(9),
354 MDIO_BUS_STATS_ADDR_ATTR_GROUP(10),
355 MDIO_BUS_STATS_ADDR_ATTR_GROUP(11),
356 MDIO_BUS_STATS_ADDR_ATTR_GROUP(12),
357 MDIO_BUS_STATS_ADDR_ATTR_GROUP(13),
358 MDIO_BUS_STATS_ADDR_ATTR_GROUP(14),
359 MDIO_BUS_STATS_ADDR_ATTR_GROUP(15),
360 MDIO_BUS_STATS_ADDR_ATTR_GROUP(16),
361 MDIO_BUS_STATS_ADDR_ATTR_GROUP(17),
362 MDIO_BUS_STATS_ADDR_ATTR_GROUP(18),
363 MDIO_BUS_STATS_ADDR_ATTR_GROUP(19),
364 MDIO_BUS_STATS_ADDR_ATTR_GROUP(20),
365 MDIO_BUS_STATS_ADDR_ATTR_GROUP(21),
366 MDIO_BUS_STATS_ADDR_ATTR_GROUP(22),
367 MDIO_BUS_STATS_ADDR_ATTR_GROUP(23),
368 MDIO_BUS_STATS_ADDR_ATTR_GROUP(24),
369 MDIO_BUS_STATS_ADDR_ATTR_GROUP(25),
370 MDIO_BUS_STATS_ADDR_ATTR_GROUP(26),
371 MDIO_BUS_STATS_ADDR_ATTR_GROUP(27),
372 MDIO_BUS_STATS_ADDR_ATTR_GROUP(28),
373 MDIO_BUS_STATS_ADDR_ATTR_GROUP(29),
374 MDIO_BUS_STATS_ADDR_ATTR_GROUP(30),
375 MDIO_BUS_STATS_ADDR_ATTR_GROUP(31),
376 NULL,
377};
378
379static const struct attribute_group mdio_bus_statistics_group = {
380 .name = "statistics",
381 .attrs = mdio_bus_statistics_attrs,
382};
383
384static const struct attribute_group *mdio_bus_groups[] = {
385 &mdio_bus_statistics_group,
386 NULL,
387};
388
389static struct class mdio_bus_class = {
390 .name = "mdio_bus",
391 .dev_release = mdiobus_release,
392 .dev_groups = mdio_bus_groups,
393};
394
395/**
396 * mdio_find_bus - Given the name of a mdiobus, find the mii_bus.
397 * @mdio_name: The name of a mdiobus.
398 *
399 * Returns a reference to the mii_bus, or NULL if none found. The
400 * embedded struct device will have its reference count incremented,
401 * and this must be put_deviced'ed once the bus is finished with.
402 */
403struct mii_bus *mdio_find_bus(const char *mdio_name)
404{
405 struct device *d;
406
407 d = class_find_device_by_name(&mdio_bus_class, mdio_name);
408 return d ? to_mii_bus(d) : NULL;
409}
410EXPORT_SYMBOL(mdio_find_bus);
411
412#if IS_ENABLED(CONFIG_OF_MDIO)
413/**
414 * of_mdio_find_bus - Given an mii_bus node, find the mii_bus.
415 * @mdio_bus_np: Pointer to the mii_bus.
416 *
417 * Returns a reference to the mii_bus, or NULL if none found. The
418 * embedded struct device will have its reference count incremented,
419 * and this must be put once the bus is finished with.
420 *
421 * Because the association of a device_node and mii_bus is made via
422 * of_mdiobus_register(), the mii_bus cannot be found before it is
423 * registered with of_mdiobus_register().
424 *
425 */
426struct mii_bus *of_mdio_find_bus(struct device_node *mdio_bus_np)
427{
428 struct device *d;
429
430 if (!mdio_bus_np)
431 return NULL;
432
433 d = class_find_device_by_of_node(&mdio_bus_class, mdio_bus_np);
434 return d ? to_mii_bus(d) : NULL;
435}
436EXPORT_SYMBOL(of_mdio_find_bus);
437
438/* Walk the list of subnodes of a mdio bus and look for a node that
439 * matches the mdio device's address with its 'reg' property. If
440 * found, set the of_node pointer for the mdio device. This allows
441 * auto-probed phy devices to be supplied with information passed in
442 * via DT.
443 */
444static void of_mdiobus_link_mdiodev(struct mii_bus *bus,
445 struct mdio_device *mdiodev)
446{
447 struct device *dev = &mdiodev->dev;
448 struct device_node *child;
449
450 if (dev->of_node || !bus->dev.of_node)
451 return;
452
453 for_each_available_child_of_node(bus->dev.of_node, child) {
454 int addr;
455
456 addr = of_mdio_parse_addr(dev, child);
457 if (addr < 0)
458 continue;
459
460 if (addr == mdiodev->addr) {
461 dev->of_node = child;
462 dev->fwnode = 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_from_board_info - 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 to
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 BUG_ON(bus->state != MDIOBUS_ALLOCATED &&
529 bus->state != MDIOBUS_UNREGISTERED);
530
531 bus->owner = owner;
532 bus->dev.parent = bus->parent;
533 bus->dev.class = &mdio_bus_class;
534 bus->dev.groups = NULL;
535 dev_set_name(&bus->dev, "%s", bus->id);
536
537 err = device_register(&bus->dev);
538 if (err) {
539 pr_err("mii_bus %s failed to register\n", bus->id);
540 return -EINVAL;
541 }
542
543 mutex_init(&bus->mdio_lock);
544 mutex_init(&bus->shared_lock);
545
546 /* de-assert bus level PHY GPIO reset */
547 gpiod = devm_gpiod_get_optional(&bus->dev, "reset", GPIOD_OUT_LOW);
548 if (IS_ERR(gpiod)) {
549 dev_err(&bus->dev, "mii_bus %s couldn't get reset GPIO\n",
550 bus->id);
551 device_del(&bus->dev);
552 return PTR_ERR(gpiod);
553 } else if (gpiod) {
554 bus->reset_gpiod = gpiod;
555
556 gpiod_set_value_cansleep(gpiod, 1);
557 fsleep(bus->reset_delay_us);
558 gpiod_set_value_cansleep(gpiod, 0);
559 if (bus->reset_post_delay_us > 0)
560 fsleep(bus->reset_post_delay_us);
561 }
562
563 if (bus->reset) {
564 err = bus->reset(bus);
565 if (err)
566 goto error_reset_gpiod;
567 }
568
569 for (i = 0; i < PHY_MAX_ADDR; i++) {
570 if ((bus->phy_mask & (1 << i)) == 0) {
571 struct phy_device *phydev;
572
573 phydev = mdiobus_scan(bus, i);
574 if (IS_ERR(phydev) && (PTR_ERR(phydev) != -ENODEV)) {
575 err = PTR_ERR(phydev);
576 goto error;
577 }
578 }
579 }
580
581 mdiobus_setup_mdiodev_from_board_info(bus, mdiobus_create_device);
582
583 bus->state = MDIOBUS_REGISTERED;
584 pr_info("%s: probed\n", bus->name);
585 return 0;
586
587error:
588 while (--i >= 0) {
589 mdiodev = bus->mdio_map[i];
590 if (!mdiodev)
591 continue;
592
593 mdiodev->device_remove(mdiodev);
594 mdiodev->device_free(mdiodev);
595 }
596error_reset_gpiod:
597 /* Put PHYs in RESET to save power */
598 if (bus->reset_gpiod)
599 gpiod_set_value_cansleep(bus->reset_gpiod, 1);
600
601 device_del(&bus->dev);
602 return err;
603}
604EXPORT_SYMBOL(__mdiobus_register);
605
606void mdiobus_unregister(struct mii_bus *bus)
607{
608 struct mdio_device *mdiodev;
609 int i;
610
611 BUG_ON(bus->state != MDIOBUS_REGISTERED);
612 bus->state = MDIOBUS_UNREGISTERED;
613
614 for (i = 0; i < PHY_MAX_ADDR; i++) {
615 mdiodev = bus->mdio_map[i];
616 if (!mdiodev)
617 continue;
618
619 if (mdiodev->reset_gpio)
620 gpiod_put(mdiodev->reset_gpio);
621
622 mdiodev->device_remove(mdiodev);
623 mdiodev->device_free(mdiodev);
624 }
625
626 /* Put PHYs in RESET to save power */
627 if (bus->reset_gpiod)
628 gpiod_set_value_cansleep(bus->reset_gpiod, 1);
629
630 device_del(&bus->dev);
631}
632EXPORT_SYMBOL(mdiobus_unregister);
633
634/**
635 * mdiobus_free - free a struct mii_bus
636 * @bus: mii_bus to free
637 *
638 * This function releases the reference to the underlying device
639 * object in the mii_bus. If this is the last reference, the mii_bus
640 * will be freed.
641 */
642void mdiobus_free(struct mii_bus *bus)
643{
644 /* For compatibility with error handling in drivers. */
645 if (bus->state == MDIOBUS_ALLOCATED) {
646 kfree(bus);
647 return;
648 }
649
650 BUG_ON(bus->state != MDIOBUS_UNREGISTERED);
651 bus->state = MDIOBUS_RELEASED;
652
653 put_device(&bus->dev);
654}
655EXPORT_SYMBOL(mdiobus_free);
656
657/**
658 * mdiobus_scan - scan a bus for MDIO devices.
659 * @bus: mii_bus to scan
660 * @addr: address on bus to scan
661 *
662 * This function scans the MDIO bus, looking for devices which can be
663 * identified using a vendor/product ID in registers 2 and 3. Not all
664 * MDIO devices have such registers, but PHY devices typically
665 * do. Hence this function assumes anything found is a PHY, or can be
666 * treated as a PHY. Other MDIO devices, such as switches, will
667 * probably not be found during the scan.
668 */
669struct phy_device *mdiobus_scan(struct mii_bus *bus, int addr)
670{
671 struct phy_device *phydev = ERR_PTR(-ENODEV);
672 int err;
673
674 switch (bus->probe_capabilities) {
675 case MDIOBUS_NO_CAP:
676 case MDIOBUS_C22:
677 phydev = get_phy_device(bus, addr, false);
678 break;
679 case MDIOBUS_C45:
680 phydev = get_phy_device(bus, addr, true);
681 break;
682 case MDIOBUS_C22_C45:
683 phydev = get_phy_device(bus, addr, false);
684 if (IS_ERR(phydev))
685 phydev = get_phy_device(bus, addr, true);
686 break;
687 }
688
689 if (IS_ERR(phydev))
690 return phydev;
691
692 /*
693 * For DT, see if the auto-probed phy has a correspoding child
694 * in the bus node, and set the of_node pointer in this case.
695 */
696 of_mdiobus_link_mdiodev(bus, &phydev->mdio);
697
698 err = phy_device_register(phydev);
699 if (err) {
700 phy_device_free(phydev);
701 return ERR_PTR(-ENODEV);
702 }
703
704 return phydev;
705}
706EXPORT_SYMBOL(mdiobus_scan);
707
708static void mdiobus_stats_acct(struct mdio_bus_stats *stats, bool op, int ret)
709{
710 preempt_disable();
711 u64_stats_update_begin(&stats->syncp);
712
713 u64_stats_inc(&stats->transfers);
714 if (ret < 0) {
715 u64_stats_inc(&stats->errors);
716 goto out;
717 }
718
719 if (op)
720 u64_stats_inc(&stats->reads);
721 else
722 u64_stats_inc(&stats->writes);
723out:
724 u64_stats_update_end(&stats->syncp);
725 preempt_enable();
726}
727
728/**
729 * __mdiobus_read - Unlocked version of the mdiobus_read function
730 * @bus: the mii_bus struct
731 * @addr: the phy address
732 * @regnum: register number to read
733 *
734 * Read a MDIO bus register. Caller must hold the mdio bus lock.
735 *
736 * NOTE: MUST NOT be called from interrupt context.
737 */
738int __mdiobus_read(struct mii_bus *bus, int addr, u32 regnum)
739{
740 int retval;
741
742 WARN_ON_ONCE(!mutex_is_locked(&bus->mdio_lock));
743
744 retval = bus->read(bus, addr, regnum);
745
746 trace_mdio_access(bus, 1, addr, regnum, retval, retval);
747 mdiobus_stats_acct(&bus->stats[addr], true, retval);
748
749 return retval;
750}
751EXPORT_SYMBOL(__mdiobus_read);
752
753/**
754 * __mdiobus_write - Unlocked version of the mdiobus_write function
755 * @bus: the mii_bus struct
756 * @addr: the phy address
757 * @regnum: register number to write
758 * @val: value to write to @regnum
759 *
760 * Write a MDIO bus register. Caller must hold the mdio bus lock.
761 *
762 * NOTE: MUST NOT be called from interrupt context.
763 */
764int __mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val)
765{
766 int err;
767
768 WARN_ON_ONCE(!mutex_is_locked(&bus->mdio_lock));
769
770 err = bus->write(bus, addr, regnum, val);
771
772 trace_mdio_access(bus, 0, addr, regnum, val, err);
773 mdiobus_stats_acct(&bus->stats[addr], false, err);
774
775 return err;
776}
777EXPORT_SYMBOL(__mdiobus_write);
778
779/**
780 * __mdiobus_modify_changed - Unlocked version of the mdiobus_modify function
781 * @bus: the mii_bus struct
782 * @addr: the phy address
783 * @regnum: register number to modify
784 * @mask: bit mask of bits to clear
785 * @set: bit mask of bits to set
786 *
787 * Read, modify, and if any change, write the register value back to the
788 * device. Any error returns a negative number.
789 *
790 * NOTE: MUST NOT be called from interrupt context.
791 */
792int __mdiobus_modify_changed(struct mii_bus *bus, int addr, u32 regnum,
793 u16 mask, u16 set)
794{
795 int new, ret;
796
797 ret = __mdiobus_read(bus, addr, regnum);
798 if (ret < 0)
799 return ret;
800
801 new = (ret & ~mask) | set;
802 if (new == ret)
803 return 0;
804
805 ret = __mdiobus_write(bus, addr, regnum, new);
806
807 return ret < 0 ? ret : 1;
808}
809EXPORT_SYMBOL_GPL(__mdiobus_modify_changed);
810
811/**
812 * mdiobus_read_nested - Nested version of the mdiobus_read function
813 * @bus: the mii_bus struct
814 * @addr: the phy address
815 * @regnum: register number to read
816 *
817 * In case of nested MDIO bus access avoid lockdep false positives by
818 * using mutex_lock_nested().
819 *
820 * NOTE: MUST NOT be called from interrupt context,
821 * because the bus read/write functions may wait for an interrupt
822 * to conclude the operation.
823 */
824int mdiobus_read_nested(struct mii_bus *bus, int addr, u32 regnum)
825{
826 int retval;
827
828 if (WARN_ON_ONCE(in_interrupt()))
829 return -EINVAL;
830
831 mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED);
832 retval = __mdiobus_read(bus, addr, regnum);
833 mutex_unlock(&bus->mdio_lock);
834
835 return retval;
836}
837EXPORT_SYMBOL(mdiobus_read_nested);
838
839/**
840 * mdiobus_read - Convenience function for reading a given MII mgmt register
841 * @bus: the mii_bus struct
842 * @addr: the phy address
843 * @regnum: register number to read
844 *
845 * NOTE: MUST NOT be called from interrupt context,
846 * because the bus read/write functions may wait for an interrupt
847 * to conclude the operation.
848 */
849int mdiobus_read(struct mii_bus *bus, int addr, u32 regnum)
850{
851 int retval;
852
853 if (WARN_ON_ONCE(in_interrupt()))
854 return -EINVAL;
855
856 mutex_lock(&bus->mdio_lock);
857 retval = __mdiobus_read(bus, addr, regnum);
858 mutex_unlock(&bus->mdio_lock);
859
860 return retval;
861}
862EXPORT_SYMBOL(mdiobus_read);
863
864/**
865 * mdiobus_write_nested - Nested version of the mdiobus_write function
866 * @bus: the mii_bus struct
867 * @addr: the phy address
868 * @regnum: register number to write
869 * @val: value to write to @regnum
870 *
871 * In case of nested MDIO bus access avoid lockdep false positives by
872 * using mutex_lock_nested().
873 *
874 * NOTE: MUST NOT be called from interrupt context,
875 * because the bus read/write functions may wait for an interrupt
876 * to conclude the operation.
877 */
878int mdiobus_write_nested(struct mii_bus *bus, int addr, u32 regnum, u16 val)
879{
880 int err;
881
882 if (WARN_ON_ONCE(in_interrupt()))
883 return -EINVAL;
884
885 mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED);
886 err = __mdiobus_write(bus, addr, regnum, val);
887 mutex_unlock(&bus->mdio_lock);
888
889 return err;
890}
891EXPORT_SYMBOL(mdiobus_write_nested);
892
893/**
894 * mdiobus_write - Convenience function for writing a given MII mgmt register
895 * @bus: the mii_bus struct
896 * @addr: the phy address
897 * @regnum: register number to write
898 * @val: value to write to @regnum
899 *
900 * NOTE: MUST NOT be called from interrupt context,
901 * because the bus read/write functions may wait for an interrupt
902 * to conclude the operation.
903 */
904int mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val)
905{
906 int err;
907
908 if (WARN_ON_ONCE(in_interrupt()))
909 return -EINVAL;
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 if (WARN_ON_ONCE(in_interrupt()))
933 return -EINVAL;
934
935 mutex_lock(&bus->mdio_lock);
936 err = __mdiobus_modify_changed(bus, addr, regnum, mask, set);
937 mutex_unlock(&bus->mdio_lock);
938
939 return err < 0 ? err : 0;
940}
941EXPORT_SYMBOL_GPL(mdiobus_modify);
942
943/**
944 * mdio_bus_match - determine if given MDIO driver supports the given
945 * MDIO device
946 * @dev: target MDIO device
947 * @drv: given MDIO driver
948 *
949 * Description: Given a MDIO device, and a MDIO driver, return 1 if
950 * the driver supports the device. Otherwise, return 0. This may
951 * require calling the devices own match function, since different classes
952 * of MDIO devices have different match criteria.
953 */
954static int mdio_bus_match(struct device *dev, struct device_driver *drv)
955{
956 struct mdio_device *mdio = to_mdio_device(dev);
957
958 if (of_driver_match_device(dev, drv))
959 return 1;
960
961 if (mdio->bus_match)
962 return mdio->bus_match(dev, drv);
963
964 return 0;
965}
966
967static int mdio_uevent(struct device *dev, struct kobj_uevent_env *env)
968{
969 int rc;
970
971 /* Some devices have extra OF data and an OF-style MODALIAS */
972 rc = of_device_uevent_modalias(dev, env);
973 if (rc != -ENODEV)
974 return rc;
975
976 return 0;
977}
978
979static struct attribute *mdio_bus_device_statistics_attrs[] = {
980 &dev_attr_mdio_bus_device_transfers.attr.attr,
981 &dev_attr_mdio_bus_device_errors.attr.attr,
982 &dev_attr_mdio_bus_device_writes.attr.attr,
983 &dev_attr_mdio_bus_device_reads.attr.attr,
984 NULL,
985};
986
987static const struct attribute_group mdio_bus_device_statistics_group = {
988 .name = "statistics",
989 .attrs = mdio_bus_device_statistics_attrs,
990};
991
992static const struct attribute_group *mdio_bus_dev_groups[] = {
993 &mdio_bus_device_statistics_group,
994 NULL,
995};
996
997struct bus_type mdio_bus_type = {
998 .name = "mdio_bus",
999 .dev_groups = mdio_bus_dev_groups,
1000 .match = mdio_bus_match,
1001 .uevent = mdio_uevent,
1002};
1003EXPORT_SYMBOL(mdio_bus_type);
1004
1005int __init mdio_bus_init(void)
1006{
1007 int ret;
1008
1009 ret = class_register(&mdio_bus_class);
1010 if (!ret) {
1011 ret = bus_register(&mdio_bus_type);
1012 if (ret)
1013 class_unregister(&mdio_bus_class);
1014 }
1015
1016 return ret;
1017}
1018EXPORT_SYMBOL_GPL(mdio_bus_init);
1019
1020#if IS_ENABLED(CONFIG_PHYLIB)
1021void mdio_bus_exit(void)
1022{
1023 class_unregister(&mdio_bus_class);
1024 bus_unregister(&mdio_bus_type);
1025}
1026EXPORT_SYMBOL_GPL(mdio_bus_exit);
1027#else
1028module_init(mdio_bus_init);
1029/* no module_exit, intentional */
1030MODULE_LICENSE("GPL");
1031MODULE_DESCRIPTION("MDIO bus/device layer");
1032#endif
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;
112
113 if (addr < 0 || addr >= ARRAY_SIZE(bus->mdio_map))
114 return NULL;
115
116 mdiodev = bus->mdio_map[addr];
117
118 if (!mdiodev)
119 return NULL;
120
121 if (!(mdiodev->flags & MDIO_DEVICE_FLAG_PHY))
122 return NULL;
123
124 return container_of(mdiodev, struct phy_device, mdio);
125}
126EXPORT_SYMBOL(mdiobus_get_phy);
127
128bool mdiobus_is_registered_device(struct mii_bus *bus, int addr)
129{
130 return bus->mdio_map[addr];
131}
132EXPORT_SYMBOL(mdiobus_is_registered_device);
133
134/**
135 * mdiobus_alloc_size - allocate a mii_bus structure
136 * @size: extra amount of memory to allocate for private storage.
137 * If non-zero, then bus->priv is points to that memory.
138 *
139 * Description: called by a bus driver to allocate an mii_bus
140 * structure to fill in.
141 */
142struct mii_bus *mdiobus_alloc_size(size_t size)
143{
144 struct mii_bus *bus;
145 size_t aligned_size = ALIGN(sizeof(*bus), NETDEV_ALIGN);
146 size_t alloc_size;
147 int i;
148
149 /* If we alloc extra space, it should be aligned */
150 if (size)
151 alloc_size = aligned_size + size;
152 else
153 alloc_size = sizeof(*bus);
154
155 bus = kzalloc(alloc_size, GFP_KERNEL);
156 if (!bus)
157 return NULL;
158
159 bus->state = MDIOBUS_ALLOCATED;
160 if (size)
161 bus->priv = (void *)bus + aligned_size;
162
163 /* Initialise the interrupts to polling and 64-bit seqcounts */
164 for (i = 0; i < PHY_MAX_ADDR; i++) {
165 bus->irq[i] = PHY_POLL;
166 u64_stats_init(&bus->stats[i].syncp);
167 }
168
169 return bus;
170}
171EXPORT_SYMBOL(mdiobus_alloc_size);
172
173/**
174 * mdiobus_release - mii_bus device release callback
175 * @d: the target struct device that contains the mii_bus
176 *
177 * Description: called when the last reference to an mii_bus is
178 * dropped, to free the underlying memory.
179 */
180static void mdiobus_release(struct device *d)
181{
182 struct mii_bus *bus = to_mii_bus(d);
183
184 WARN(bus->state != MDIOBUS_RELEASED &&
185 /* for compatibility with error handling in drivers */
186 bus->state != MDIOBUS_ALLOCATED,
187 "%s: not in RELEASED or ALLOCATED state\n",
188 bus->id);
189 kfree(bus);
190}
191
192struct mdio_bus_stat_attr {
193 int addr;
194 unsigned int field_offset;
195};
196
197static u64 mdio_bus_get_stat(struct mdio_bus_stats *s, unsigned int offset)
198{
199 const char *p = (const char *)s + offset;
200 unsigned int start;
201 u64 val = 0;
202
203 do {
204 start = u64_stats_fetch_begin(&s->syncp);
205 val = u64_stats_read((const u64_stats_t *)p);
206 } while (u64_stats_fetch_retry(&s->syncp, start));
207
208 return val;
209}
210
211static u64 mdio_bus_get_global_stat(struct mii_bus *bus, unsigned int offset)
212{
213 unsigned int i;
214 u64 val = 0;
215
216 for (i = 0; i < PHY_MAX_ADDR; i++)
217 val += mdio_bus_get_stat(&bus->stats[i], offset);
218
219 return val;
220}
221
222static ssize_t mdio_bus_stat_field_show(struct device *dev,
223 struct device_attribute *attr,
224 char *buf)
225{
226 struct mii_bus *bus = to_mii_bus(dev);
227 struct mdio_bus_stat_attr *sattr;
228 struct dev_ext_attribute *eattr;
229 u64 val;
230
231 eattr = container_of(attr, struct dev_ext_attribute, attr);
232 sattr = eattr->var;
233
234 if (sattr->addr < 0)
235 val = mdio_bus_get_global_stat(bus, sattr->field_offset);
236 else
237 val = mdio_bus_get_stat(&bus->stats[sattr->addr],
238 sattr->field_offset);
239
240 return sysfs_emit(buf, "%llu\n", val);
241}
242
243static ssize_t mdio_bus_device_stat_field_show(struct device *dev,
244 struct device_attribute *attr,
245 char *buf)
246{
247 struct mdio_device *mdiodev = to_mdio_device(dev);
248 struct mii_bus *bus = mdiodev->bus;
249 struct mdio_bus_stat_attr *sattr;
250 struct dev_ext_attribute *eattr;
251 int addr = mdiodev->addr;
252 u64 val;
253
254 eattr = container_of(attr, struct dev_ext_attribute, attr);
255 sattr = eattr->var;
256
257 val = mdio_bus_get_stat(&bus->stats[addr], sattr->field_offset);
258
259 return sysfs_emit(buf, "%llu\n", val);
260}
261
262#define MDIO_BUS_STATS_ATTR_DECL(field, file) \
263static struct dev_ext_attribute dev_attr_mdio_bus_##field = { \
264 .attr = { .attr = { .name = file, .mode = 0444 }, \
265 .show = mdio_bus_stat_field_show, \
266 }, \
267 .var = &((struct mdio_bus_stat_attr) { \
268 -1, offsetof(struct mdio_bus_stats, field) \
269 }), \
270}; \
271static struct dev_ext_attribute dev_attr_mdio_bus_device_##field = { \
272 .attr = { .attr = { .name = file, .mode = 0444 }, \
273 .show = mdio_bus_device_stat_field_show, \
274 }, \
275 .var = &((struct mdio_bus_stat_attr) { \
276 -1, offsetof(struct mdio_bus_stats, field) \
277 }), \
278};
279
280#define MDIO_BUS_STATS_ATTR(field) \
281 MDIO_BUS_STATS_ATTR_DECL(field, __stringify(field))
282
283MDIO_BUS_STATS_ATTR(transfers);
284MDIO_BUS_STATS_ATTR(errors);
285MDIO_BUS_STATS_ATTR(writes);
286MDIO_BUS_STATS_ATTR(reads);
287
288#define MDIO_BUS_STATS_ADDR_ATTR_DECL(field, addr, file) \
289static struct dev_ext_attribute dev_attr_mdio_bus_addr_##field##_##addr = { \
290 .attr = { .attr = { .name = file, .mode = 0444 }, \
291 .show = mdio_bus_stat_field_show, \
292 }, \
293 .var = &((struct mdio_bus_stat_attr) { \
294 addr, offsetof(struct mdio_bus_stats, field) \
295 }), \
296}
297
298#define MDIO_BUS_STATS_ADDR_ATTR(field, addr) \
299 MDIO_BUS_STATS_ADDR_ATTR_DECL(field, addr, \
300 __stringify(field) "_" __stringify(addr))
301
302#define MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(addr) \
303 MDIO_BUS_STATS_ADDR_ATTR(transfers, addr); \
304 MDIO_BUS_STATS_ADDR_ATTR(errors, addr); \
305 MDIO_BUS_STATS_ADDR_ATTR(writes, addr); \
306 MDIO_BUS_STATS_ADDR_ATTR(reads, addr) \
307
308MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(0);
309MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(1);
310MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(2);
311MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(3);
312MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(4);
313MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(5);
314MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(6);
315MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(7);
316MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(8);
317MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(9);
318MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(10);
319MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(11);
320MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(12);
321MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(13);
322MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(14);
323MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(15);
324MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(16);
325MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(17);
326MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(18);
327MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(19);
328MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(20);
329MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(21);
330MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(22);
331MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(23);
332MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(24);
333MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(25);
334MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(26);
335MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(27);
336MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(28);
337MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(29);
338MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(30);
339MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(31);
340
341#define MDIO_BUS_STATS_ADDR_ATTR_GROUP(addr) \
342 &dev_attr_mdio_bus_addr_transfers_##addr.attr.attr, \
343 &dev_attr_mdio_bus_addr_errors_##addr.attr.attr, \
344 &dev_attr_mdio_bus_addr_writes_##addr.attr.attr, \
345 &dev_attr_mdio_bus_addr_reads_##addr.attr.attr \
346
347static struct attribute *mdio_bus_statistics_attrs[] = {
348 &dev_attr_mdio_bus_transfers.attr.attr,
349 &dev_attr_mdio_bus_errors.attr.attr,
350 &dev_attr_mdio_bus_writes.attr.attr,
351 &dev_attr_mdio_bus_reads.attr.attr,
352 MDIO_BUS_STATS_ADDR_ATTR_GROUP(0),
353 MDIO_BUS_STATS_ADDR_ATTR_GROUP(1),
354 MDIO_BUS_STATS_ADDR_ATTR_GROUP(2),
355 MDIO_BUS_STATS_ADDR_ATTR_GROUP(3),
356 MDIO_BUS_STATS_ADDR_ATTR_GROUP(4),
357 MDIO_BUS_STATS_ADDR_ATTR_GROUP(5),
358 MDIO_BUS_STATS_ADDR_ATTR_GROUP(6),
359 MDIO_BUS_STATS_ADDR_ATTR_GROUP(7),
360 MDIO_BUS_STATS_ADDR_ATTR_GROUP(8),
361 MDIO_BUS_STATS_ADDR_ATTR_GROUP(9),
362 MDIO_BUS_STATS_ADDR_ATTR_GROUP(10),
363 MDIO_BUS_STATS_ADDR_ATTR_GROUP(11),
364 MDIO_BUS_STATS_ADDR_ATTR_GROUP(12),
365 MDIO_BUS_STATS_ADDR_ATTR_GROUP(13),
366 MDIO_BUS_STATS_ADDR_ATTR_GROUP(14),
367 MDIO_BUS_STATS_ADDR_ATTR_GROUP(15),
368 MDIO_BUS_STATS_ADDR_ATTR_GROUP(16),
369 MDIO_BUS_STATS_ADDR_ATTR_GROUP(17),
370 MDIO_BUS_STATS_ADDR_ATTR_GROUP(18),
371 MDIO_BUS_STATS_ADDR_ATTR_GROUP(19),
372 MDIO_BUS_STATS_ADDR_ATTR_GROUP(20),
373 MDIO_BUS_STATS_ADDR_ATTR_GROUP(21),
374 MDIO_BUS_STATS_ADDR_ATTR_GROUP(22),
375 MDIO_BUS_STATS_ADDR_ATTR_GROUP(23),
376 MDIO_BUS_STATS_ADDR_ATTR_GROUP(24),
377 MDIO_BUS_STATS_ADDR_ATTR_GROUP(25),
378 MDIO_BUS_STATS_ADDR_ATTR_GROUP(26),
379 MDIO_BUS_STATS_ADDR_ATTR_GROUP(27),
380 MDIO_BUS_STATS_ADDR_ATTR_GROUP(28),
381 MDIO_BUS_STATS_ADDR_ATTR_GROUP(29),
382 MDIO_BUS_STATS_ADDR_ATTR_GROUP(30),
383 MDIO_BUS_STATS_ADDR_ATTR_GROUP(31),
384 NULL,
385};
386
387static const struct attribute_group mdio_bus_statistics_group = {
388 .name = "statistics",
389 .attrs = mdio_bus_statistics_attrs,
390};
391
392static const struct attribute_group *mdio_bus_groups[] = {
393 &mdio_bus_statistics_group,
394 NULL,
395};
396
397static struct class mdio_bus_class = {
398 .name = "mdio_bus",
399 .dev_release = mdiobus_release,
400 .dev_groups = mdio_bus_groups,
401};
402
403/**
404 * mdio_find_bus - Given the name of a mdiobus, find the mii_bus.
405 * @mdio_name: The name of a mdiobus.
406 *
407 * Returns a reference to the mii_bus, or NULL if none found. The
408 * embedded struct device will have its reference count incremented,
409 * and this must be put_deviced'ed once the bus is finished with.
410 */
411struct mii_bus *mdio_find_bus(const char *mdio_name)
412{
413 struct device *d;
414
415 d = class_find_device_by_name(&mdio_bus_class, mdio_name);
416 return d ? to_mii_bus(d) : NULL;
417}
418EXPORT_SYMBOL(mdio_find_bus);
419
420#if IS_ENABLED(CONFIG_OF_MDIO)
421/**
422 * of_mdio_find_bus - Given an mii_bus node, find the mii_bus.
423 * @mdio_bus_np: Pointer to the mii_bus.
424 *
425 * Returns a reference to the mii_bus, or NULL if none found. The
426 * embedded struct device will have its reference count incremented,
427 * and this must be put once the bus is finished with.
428 *
429 * Because the association of a device_node and mii_bus is made via
430 * of_mdiobus_register(), the mii_bus cannot be found before it is
431 * registered with of_mdiobus_register().
432 *
433 */
434struct mii_bus *of_mdio_find_bus(struct device_node *mdio_bus_np)
435{
436 struct device *d;
437
438 if (!mdio_bus_np)
439 return NULL;
440
441 d = class_find_device_by_of_node(&mdio_bus_class, mdio_bus_np);
442 return d ? to_mii_bus(d) : NULL;
443}
444EXPORT_SYMBOL(of_mdio_find_bus);
445
446/* Walk the list of subnodes of a mdio bus and look for a node that
447 * matches the mdio device's address with its 'reg' property. If
448 * found, set the of_node pointer for the mdio device. This allows
449 * auto-probed phy devices to be supplied with information passed in
450 * via DT.
451 */
452static void of_mdiobus_link_mdiodev(struct mii_bus *bus,
453 struct mdio_device *mdiodev)
454{
455 struct device *dev = &mdiodev->dev;
456 struct device_node *child;
457
458 if (dev->of_node || !bus->dev.of_node)
459 return;
460
461 for_each_available_child_of_node(bus->dev.of_node, child) {
462 int addr;
463
464 addr = of_mdio_parse_addr(dev, child);
465 if (addr < 0)
466 continue;
467
468 if (addr == mdiodev->addr) {
469 device_set_node(dev, of_fwnode_handle(child));
470 /* The refcount on "child" is passed to the mdio
471 * device. Do _not_ use of_node_put(child) here.
472 */
473 return;
474 }
475 }
476}
477#else /* !IS_ENABLED(CONFIG_OF_MDIO) */
478static inline void of_mdiobus_link_mdiodev(struct mii_bus *mdio,
479 struct mdio_device *mdiodev)
480{
481}
482#endif
483
484/**
485 * mdiobus_create_device - create a full MDIO device given
486 * a mdio_board_info structure
487 * @bus: MDIO bus to create the devices on
488 * @bi: mdio_board_info structure describing the devices
489 *
490 * Returns 0 on success or < 0 on error.
491 */
492static int mdiobus_create_device(struct mii_bus *bus,
493 struct mdio_board_info *bi)
494{
495 struct mdio_device *mdiodev;
496 int ret = 0;
497
498 mdiodev = mdio_device_create(bus, bi->mdio_addr);
499 if (IS_ERR(mdiodev))
500 return -ENODEV;
501
502 strncpy(mdiodev->modalias, bi->modalias,
503 sizeof(mdiodev->modalias));
504 mdiodev->bus_match = mdio_device_bus_match;
505 mdiodev->dev.platform_data = (void *)bi->platform_data;
506
507 ret = mdio_device_register(mdiodev);
508 if (ret)
509 mdio_device_free(mdiodev);
510
511 return ret;
512}
513
514/**
515 * __mdiobus_register - bring up all the PHYs on a given bus and attach them to bus
516 * @bus: target mii_bus
517 * @owner: module containing bus accessor functions
518 *
519 * Description: Called by a bus driver to bring up all the PHYs
520 * on a given bus, and attach them to the bus. Drivers should use
521 * mdiobus_register() rather than __mdiobus_register() unless they
522 * need to pass a specific owner module. MDIO devices which are not
523 * PHYs will not be brought up by this function. They are expected
524 * to be explicitly listed in DT and instantiated by of_mdiobus_register().
525 *
526 * Returns 0 on success or < 0 on error.
527 */
528int __mdiobus_register(struct mii_bus *bus, struct module *owner)
529{
530 struct mdio_device *mdiodev;
531 int i, err;
532 struct gpio_desc *gpiod;
533
534 if (NULL == bus || NULL == bus->name ||
535 NULL == bus->read || NULL == bus->write)
536 return -EINVAL;
537
538 if (bus->parent && bus->parent->of_node)
539 bus->parent->of_node->fwnode.flags |=
540 FWNODE_FLAG_NEEDS_CHILD_BOUND_ON_ADD;
541
542 WARN(bus->state != MDIOBUS_ALLOCATED &&
543 bus->state != MDIOBUS_UNREGISTERED,
544 "%s: not in ALLOCATED or UNREGISTERED state\n", bus->id);
545
546 bus->owner = owner;
547 bus->dev.parent = bus->parent;
548 bus->dev.class = &mdio_bus_class;
549 bus->dev.groups = NULL;
550 dev_set_name(&bus->dev, "%s", bus->id);
551
552 /* We need to set state to MDIOBUS_UNREGISTERED to correctly release
553 * the device in mdiobus_free()
554 *
555 * State will be updated later in this function in case of success
556 */
557 bus->state = MDIOBUS_UNREGISTERED;
558
559 err = device_register(&bus->dev);
560 if (err) {
561 pr_err("mii_bus %s failed to register\n", bus->id);
562 return -EINVAL;
563 }
564
565 mutex_init(&bus->mdio_lock);
566 mutex_init(&bus->shared_lock);
567
568 /* assert bus level PHY GPIO reset */
569 gpiod = devm_gpiod_get_optional(&bus->dev, "reset", GPIOD_OUT_HIGH);
570 if (IS_ERR(gpiod)) {
571 err = dev_err_probe(&bus->dev, PTR_ERR(gpiod),
572 "mii_bus %s couldn't get reset GPIO\n",
573 bus->id);
574 device_del(&bus->dev);
575 return err;
576 } else if (gpiod) {
577 bus->reset_gpiod = gpiod;
578 fsleep(bus->reset_delay_us);
579 gpiod_set_value_cansleep(gpiod, 0);
580 if (bus->reset_post_delay_us > 0)
581 fsleep(bus->reset_post_delay_us);
582 }
583
584 if (bus->reset) {
585 err = bus->reset(bus);
586 if (err)
587 goto error_reset_gpiod;
588 }
589
590 for (i = 0; i < PHY_MAX_ADDR; i++) {
591 if ((bus->phy_mask & BIT(i)) == 0) {
592 struct phy_device *phydev;
593
594 phydev = mdiobus_scan(bus, i);
595 if (IS_ERR(phydev) && (PTR_ERR(phydev) != -ENODEV)) {
596 err = PTR_ERR(phydev);
597 goto error;
598 }
599 }
600 }
601
602 mdiobus_setup_mdiodev_from_board_info(bus, mdiobus_create_device);
603
604 bus->state = MDIOBUS_REGISTERED;
605 dev_dbg(&bus->dev, "probed\n");
606 return 0;
607
608error:
609 while (--i >= 0) {
610 mdiodev = bus->mdio_map[i];
611 if (!mdiodev)
612 continue;
613
614 mdiodev->device_remove(mdiodev);
615 mdiodev->device_free(mdiodev);
616 }
617error_reset_gpiod:
618 /* Put PHYs in RESET to save power */
619 if (bus->reset_gpiod)
620 gpiod_set_value_cansleep(bus->reset_gpiod, 1);
621
622 device_del(&bus->dev);
623 return err;
624}
625EXPORT_SYMBOL(__mdiobus_register);
626
627void mdiobus_unregister(struct mii_bus *bus)
628{
629 struct mdio_device *mdiodev;
630 int i;
631
632 if (WARN_ON_ONCE(bus->state != MDIOBUS_REGISTERED))
633 return;
634 bus->state = MDIOBUS_UNREGISTERED;
635
636 for (i = 0; i < PHY_MAX_ADDR; i++) {
637 mdiodev = bus->mdio_map[i];
638 if (!mdiodev)
639 continue;
640
641 if (mdiodev->reset_gpio)
642 gpiod_put(mdiodev->reset_gpio);
643
644 mdiodev->device_remove(mdiodev);
645 mdiodev->device_free(mdiodev);
646 }
647
648 /* Put PHYs in RESET to save power */
649 if (bus->reset_gpiod)
650 gpiod_set_value_cansleep(bus->reset_gpiod, 1);
651
652 device_del(&bus->dev);
653}
654EXPORT_SYMBOL(mdiobus_unregister);
655
656/**
657 * mdiobus_free - free a struct mii_bus
658 * @bus: mii_bus to free
659 *
660 * This function releases the reference to the underlying device
661 * object in the mii_bus. If this is the last reference, the mii_bus
662 * will be freed.
663 */
664void mdiobus_free(struct mii_bus *bus)
665{
666 /* For compatibility with error handling in drivers. */
667 if (bus->state == MDIOBUS_ALLOCATED) {
668 kfree(bus);
669 return;
670 }
671
672 WARN(bus->state != MDIOBUS_UNREGISTERED,
673 "%s: not in UNREGISTERED state\n", bus->id);
674 bus->state = MDIOBUS_RELEASED;
675
676 put_device(&bus->dev);
677}
678EXPORT_SYMBOL(mdiobus_free);
679
680/**
681 * mdiobus_scan - scan a bus for MDIO devices.
682 * @bus: mii_bus to scan
683 * @addr: address on bus to scan
684 *
685 * This function scans the MDIO bus, looking for devices which can be
686 * identified using a vendor/product ID in registers 2 and 3. Not all
687 * MDIO devices have such registers, but PHY devices typically
688 * do. Hence this function assumes anything found is a PHY, or can be
689 * treated as a PHY. Other MDIO devices, such as switches, will
690 * probably not be found during the scan.
691 */
692struct phy_device *mdiobus_scan(struct mii_bus *bus, int addr)
693{
694 struct phy_device *phydev = ERR_PTR(-ENODEV);
695 int err;
696
697 switch (bus->probe_capabilities) {
698 case MDIOBUS_NO_CAP:
699 case MDIOBUS_C22:
700 phydev = get_phy_device(bus, addr, false);
701 break;
702 case MDIOBUS_C45:
703 phydev = get_phy_device(bus, addr, true);
704 break;
705 case MDIOBUS_C22_C45:
706 phydev = get_phy_device(bus, addr, false);
707 if (IS_ERR(phydev))
708 phydev = get_phy_device(bus, addr, true);
709 break;
710 }
711
712 if (IS_ERR(phydev))
713 return phydev;
714
715 /*
716 * For DT, see if the auto-probed phy has a correspoding child
717 * in the bus node, and set the of_node pointer in this case.
718 */
719 of_mdiobus_link_mdiodev(bus, &phydev->mdio);
720
721 err = phy_device_register(phydev);
722 if (err) {
723 phy_device_free(phydev);
724 return ERR_PTR(-ENODEV);
725 }
726
727 return phydev;
728}
729EXPORT_SYMBOL(mdiobus_scan);
730
731static void mdiobus_stats_acct(struct mdio_bus_stats *stats, bool op, int ret)
732{
733 preempt_disable();
734 u64_stats_update_begin(&stats->syncp);
735
736 u64_stats_inc(&stats->transfers);
737 if (ret < 0) {
738 u64_stats_inc(&stats->errors);
739 goto out;
740 }
741
742 if (op)
743 u64_stats_inc(&stats->reads);
744 else
745 u64_stats_inc(&stats->writes);
746out:
747 u64_stats_update_end(&stats->syncp);
748 preempt_enable();
749}
750
751/**
752 * __mdiobus_read - Unlocked version of the mdiobus_read function
753 * @bus: the mii_bus struct
754 * @addr: the phy address
755 * @regnum: register number to read
756 *
757 * Read a MDIO bus register. Caller must hold the mdio bus lock.
758 *
759 * NOTE: MUST NOT be called from interrupt context.
760 */
761int __mdiobus_read(struct mii_bus *bus, int addr, u32 regnum)
762{
763 int retval;
764
765 lockdep_assert_held_once(&bus->mdio_lock);
766
767 retval = bus->read(bus, addr, regnum);
768
769 trace_mdio_access(bus, 1, addr, regnum, retval, retval);
770 mdiobus_stats_acct(&bus->stats[addr], true, retval);
771
772 return retval;
773}
774EXPORT_SYMBOL(__mdiobus_read);
775
776/**
777 * __mdiobus_write - Unlocked version of the mdiobus_write function
778 * @bus: the mii_bus struct
779 * @addr: the phy address
780 * @regnum: register number to write
781 * @val: value to write to @regnum
782 *
783 * Write a MDIO bus register. Caller must hold the mdio bus lock.
784 *
785 * NOTE: MUST NOT be called from interrupt context.
786 */
787int __mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val)
788{
789 int err;
790
791 lockdep_assert_held_once(&bus->mdio_lock);
792
793 err = bus->write(bus, addr, regnum, val);
794
795 trace_mdio_access(bus, 0, addr, regnum, val, err);
796 mdiobus_stats_acct(&bus->stats[addr], false, err);
797
798 return err;
799}
800EXPORT_SYMBOL(__mdiobus_write);
801
802/**
803 * __mdiobus_modify_changed - Unlocked version of the mdiobus_modify function
804 * @bus: the mii_bus struct
805 * @addr: the phy address
806 * @regnum: register number to modify
807 * @mask: bit mask of bits to clear
808 * @set: bit mask of bits to set
809 *
810 * Read, modify, and if any change, write the register value back to the
811 * device. Any error returns a negative number.
812 *
813 * NOTE: MUST NOT be called from interrupt context.
814 */
815int __mdiobus_modify_changed(struct mii_bus *bus, int addr, u32 regnum,
816 u16 mask, u16 set)
817{
818 int new, ret;
819
820 ret = __mdiobus_read(bus, addr, regnum);
821 if (ret < 0)
822 return ret;
823
824 new = (ret & ~mask) | set;
825 if (new == ret)
826 return 0;
827
828 ret = __mdiobus_write(bus, addr, regnum, new);
829
830 return ret < 0 ? ret : 1;
831}
832EXPORT_SYMBOL_GPL(__mdiobus_modify_changed);
833
834/**
835 * mdiobus_read_nested - Nested version of the mdiobus_read function
836 * @bus: the mii_bus struct
837 * @addr: the phy address
838 * @regnum: register number to read
839 *
840 * In case of nested MDIO bus access avoid lockdep false positives by
841 * using mutex_lock_nested().
842 *
843 * NOTE: MUST NOT be called from interrupt context,
844 * because the bus read/write functions may wait for an interrupt
845 * to conclude the operation.
846 */
847int mdiobus_read_nested(struct mii_bus *bus, int addr, u32 regnum)
848{
849 int retval;
850
851 mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED);
852 retval = __mdiobus_read(bus, addr, regnum);
853 mutex_unlock(&bus->mdio_lock);
854
855 return retval;
856}
857EXPORT_SYMBOL(mdiobus_read_nested);
858
859/**
860 * mdiobus_read - Convenience function for reading a given MII mgmt register
861 * @bus: the mii_bus struct
862 * @addr: the phy address
863 * @regnum: register number to read
864 *
865 * NOTE: MUST NOT be called from interrupt context,
866 * because the bus read/write functions may wait for an interrupt
867 * to conclude the operation.
868 */
869int mdiobus_read(struct mii_bus *bus, int addr, u32 regnum)
870{
871 int retval;
872
873 mutex_lock(&bus->mdio_lock);
874 retval = __mdiobus_read(bus, addr, regnum);
875 mutex_unlock(&bus->mdio_lock);
876
877 return retval;
878}
879EXPORT_SYMBOL(mdiobus_read);
880
881/**
882 * mdiobus_write_nested - Nested version of the mdiobus_write function
883 * @bus: the mii_bus struct
884 * @addr: the phy address
885 * @regnum: register number to write
886 * @val: value to write to @regnum
887 *
888 * In case of nested MDIO bus access avoid lockdep false positives by
889 * using mutex_lock_nested().
890 *
891 * NOTE: MUST NOT be called from interrupt context,
892 * because the bus read/write functions may wait for an interrupt
893 * to conclude the operation.
894 */
895int mdiobus_write_nested(struct mii_bus *bus, int addr, u32 regnum, u16 val)
896{
897 int err;
898
899 mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED);
900 err = __mdiobus_write(bus, addr, regnum, val);
901 mutex_unlock(&bus->mdio_lock);
902
903 return err;
904}
905EXPORT_SYMBOL(mdiobus_write_nested);
906
907/**
908 * mdiobus_write - Convenience function for writing a given MII mgmt register
909 * @bus: the mii_bus struct
910 * @addr: the phy address
911 * @regnum: register number to write
912 * @val: value to write to @regnum
913 *
914 * NOTE: MUST NOT be called from interrupt context,
915 * because the bus read/write functions may wait for an interrupt
916 * to conclude the operation.
917 */
918int mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val)
919{
920 int err;
921
922 mutex_lock(&bus->mdio_lock);
923 err = __mdiobus_write(bus, addr, regnum, val);
924 mutex_unlock(&bus->mdio_lock);
925
926 return err;
927}
928EXPORT_SYMBOL(mdiobus_write);
929
930/**
931 * mdiobus_modify - Convenience function for modifying a given mdio device
932 * register
933 * @bus: the mii_bus struct
934 * @addr: the phy address
935 * @regnum: register number to write
936 * @mask: bit mask of bits to clear
937 * @set: bit mask of bits to set
938 */
939int mdiobus_modify(struct mii_bus *bus, int addr, u32 regnum, u16 mask, u16 set)
940{
941 int err;
942
943 mutex_lock(&bus->mdio_lock);
944 err = __mdiobus_modify_changed(bus, addr, regnum, mask, set);
945 mutex_unlock(&bus->mdio_lock);
946
947 return err < 0 ? err : 0;
948}
949EXPORT_SYMBOL_GPL(mdiobus_modify);
950
951/**
952 * mdiobus_modify_changed - Convenience function for modifying a given mdio
953 * device register and returning if it changed
954 * @bus: the mii_bus struct
955 * @addr: the phy address
956 * @regnum: register number to write
957 * @mask: bit mask of bits to clear
958 * @set: bit mask of bits to set
959 */
960int mdiobus_modify_changed(struct mii_bus *bus, int addr, u32 regnum,
961 u16 mask, u16 set)
962{
963 int err;
964
965 mutex_lock(&bus->mdio_lock);
966 err = __mdiobus_modify_changed(bus, addr, regnum, mask, set);
967 mutex_unlock(&bus->mdio_lock);
968
969 return err;
970}
971EXPORT_SYMBOL_GPL(mdiobus_modify_changed);
972
973/**
974 * mdio_bus_match - determine if given MDIO driver supports the given
975 * MDIO device
976 * @dev: target MDIO device
977 * @drv: given MDIO driver
978 *
979 * Description: Given a MDIO device, and a MDIO driver, return 1 if
980 * the driver supports the device. Otherwise, return 0. This may
981 * require calling the devices own match function, since different classes
982 * of MDIO devices have different match criteria.
983 */
984static int mdio_bus_match(struct device *dev, struct device_driver *drv)
985{
986 struct mdio_driver *mdiodrv = to_mdio_driver(drv);
987 struct mdio_device *mdio = to_mdio_device(dev);
988
989 /* Both the driver and device must type-match */
990 if (!(mdiodrv->mdiodrv.flags & MDIO_DEVICE_IS_PHY) !=
991 !(mdio->flags & MDIO_DEVICE_FLAG_PHY))
992 return 0;
993
994 if (of_driver_match_device(dev, drv))
995 return 1;
996
997 if (mdio->bus_match)
998 return mdio->bus_match(dev, drv);
999
1000 return 0;
1001}
1002
1003static int mdio_uevent(struct device *dev, struct kobj_uevent_env *env)
1004{
1005 int rc;
1006
1007 /* Some devices have extra OF data and an OF-style MODALIAS */
1008 rc = of_device_uevent_modalias(dev, env);
1009 if (rc != -ENODEV)
1010 return rc;
1011
1012 return 0;
1013}
1014
1015static struct attribute *mdio_bus_device_statistics_attrs[] = {
1016 &dev_attr_mdio_bus_device_transfers.attr.attr,
1017 &dev_attr_mdio_bus_device_errors.attr.attr,
1018 &dev_attr_mdio_bus_device_writes.attr.attr,
1019 &dev_attr_mdio_bus_device_reads.attr.attr,
1020 NULL,
1021};
1022
1023static const struct attribute_group mdio_bus_device_statistics_group = {
1024 .name = "statistics",
1025 .attrs = mdio_bus_device_statistics_attrs,
1026};
1027
1028static const struct attribute_group *mdio_bus_dev_groups[] = {
1029 &mdio_bus_device_statistics_group,
1030 NULL,
1031};
1032
1033struct bus_type mdio_bus_type = {
1034 .name = "mdio_bus",
1035 .dev_groups = mdio_bus_dev_groups,
1036 .match = mdio_bus_match,
1037 .uevent = mdio_uevent,
1038};
1039EXPORT_SYMBOL(mdio_bus_type);
1040
1041int __init mdio_bus_init(void)
1042{
1043 int ret;
1044
1045 ret = class_register(&mdio_bus_class);
1046 if (!ret) {
1047 ret = bus_register(&mdio_bus_type);
1048 if (ret)
1049 class_unregister(&mdio_bus_class);
1050 }
1051
1052 return ret;
1053}
1054
1055#if IS_ENABLED(CONFIG_PHYLIB)
1056void mdio_bus_exit(void)
1057{
1058 class_unregister(&mdio_bus_class);
1059 bus_unregister(&mdio_bus_type);
1060}
1061EXPORT_SYMBOL_GPL(mdio_bus_exit);
1062#else
1063module_init(mdio_bus_init);
1064/* no module_exit, intentional */
1065MODULE_LICENSE("GPL");
1066MODULE_DESCRIPTION("MDIO bus/device layer");
1067#endif