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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/micrel_phy.h>
23#include <linux/mii.h>
24#include <linux/mm.h>
25#include <linux/module.h>
26#include <linux/netdevice.h>
27#include <linux/of_device.h>
28#include <linux/of_gpio.h>
29#include <linux/of_mdio.h>
30#include <linux/phy.h>
31#include <linux/reset.h>
32#include <linux/skbuff.h>
33#include <linux/slab.h>
34#include <linux/spinlock.h>
35#include <linux/string.h>
36#include <linux/uaccess.h>
37#include <linux/unistd.h>
38
39#define CREATE_TRACE_POINTS
40#include <trace/events/mdio.h>
41
42#include "mdio-boardinfo.h"
43
44static int mdiobus_register_gpiod(struct mdio_device *mdiodev)
45{
46 /* Deassert the optional reset signal */
47 mdiodev->reset_gpio = gpiod_get_optional(&mdiodev->dev,
48 "reset", GPIOD_OUT_LOW);
49 if (IS_ERR(mdiodev->reset_gpio))
50 return PTR_ERR(mdiodev->reset_gpio);
51
52 if (mdiodev->reset_gpio)
53 gpiod_set_consumer_name(mdiodev->reset_gpio, "PHY reset");
54
55 return 0;
56}
57
58static int mdiobus_register_reset(struct mdio_device *mdiodev)
59{
60 struct reset_control *reset;
61
62 reset = reset_control_get_optional_exclusive(&mdiodev->dev, "phy");
63 if (IS_ERR(reset))
64 return PTR_ERR(reset);
65
66 mdiodev->reset_ctrl = reset;
67
68 return 0;
69}
70
71int mdiobus_register_device(struct mdio_device *mdiodev)
72{
73 int err;
74
75 if (mdiodev->bus->mdio_map[mdiodev->addr])
76 return -EBUSY;
77
78 if (mdiodev->flags & MDIO_DEVICE_FLAG_PHY) {
79 err = mdiobus_register_gpiod(mdiodev);
80 if (err)
81 return err;
82
83 err = mdiobus_register_reset(mdiodev);
84 if (err)
85 return err;
86
87 /* Assert the reset signal */
88 mdio_device_reset(mdiodev, 1);
89 }
90
91 mdiodev->bus->mdio_map[mdiodev->addr] = mdiodev;
92
93 return 0;
94}
95EXPORT_SYMBOL(mdiobus_register_device);
96
97int mdiobus_unregister_device(struct mdio_device *mdiodev)
98{
99 if (mdiodev->bus->mdio_map[mdiodev->addr] != mdiodev)
100 return -EINVAL;
101
102 reset_control_put(mdiodev->reset_ctrl);
103
104 mdiodev->bus->mdio_map[mdiodev->addr] = NULL;
105
106 return 0;
107}
108EXPORT_SYMBOL(mdiobus_unregister_device);
109
110static struct mdio_device *mdiobus_find_device(struct mii_bus *bus, int addr)
111{
112 bool addr_valid = addr >= 0 && addr < ARRAY_SIZE(bus->mdio_map);
113
114 if (WARN_ONCE(!addr_valid, "addr %d out of range\n", addr))
115 return NULL;
116
117 return bus->mdio_map[addr];
118}
119
120struct phy_device *mdiobus_get_phy(struct mii_bus *bus, int addr)
121{
122 struct mdio_device *mdiodev;
123
124 mdiodev = mdiobus_find_device(bus, addr);
125 if (!mdiodev)
126 return NULL;
127
128 if (!(mdiodev->flags & MDIO_DEVICE_FLAG_PHY))
129 return NULL;
130
131 return container_of(mdiodev, struct phy_device, mdio);
132}
133EXPORT_SYMBOL(mdiobus_get_phy);
134
135bool mdiobus_is_registered_device(struct mii_bus *bus, int addr)
136{
137 return mdiobus_find_device(bus, addr) != NULL;
138}
139EXPORT_SYMBOL(mdiobus_is_registered_device);
140
141/**
142 * mdiobus_alloc_size - allocate a mii_bus structure
143 * @size: extra amount of memory to allocate for private storage.
144 * If non-zero, then bus->priv is points to that memory.
145 *
146 * Description: called by a bus driver to allocate an mii_bus
147 * structure to fill in.
148 */
149struct mii_bus *mdiobus_alloc_size(size_t size)
150{
151 struct mii_bus *bus;
152 size_t aligned_size = ALIGN(sizeof(*bus), NETDEV_ALIGN);
153 size_t alloc_size;
154 int i;
155
156 /* If we alloc extra space, it should be aligned */
157 if (size)
158 alloc_size = aligned_size + size;
159 else
160 alloc_size = sizeof(*bus);
161
162 bus = kzalloc(alloc_size, GFP_KERNEL);
163 if (!bus)
164 return NULL;
165
166 bus->state = MDIOBUS_ALLOCATED;
167 if (size)
168 bus->priv = (void *)bus + aligned_size;
169
170 /* Initialise the interrupts to polling and 64-bit seqcounts */
171 for (i = 0; i < PHY_MAX_ADDR; i++) {
172 bus->irq[i] = PHY_POLL;
173 u64_stats_init(&bus->stats[i].syncp);
174 }
175
176 return bus;
177}
178EXPORT_SYMBOL(mdiobus_alloc_size);
179
180/**
181 * mdiobus_release - mii_bus device release callback
182 * @d: the target struct device that contains the mii_bus
183 *
184 * Description: called when the last reference to an mii_bus is
185 * dropped, to free the underlying memory.
186 */
187static void mdiobus_release(struct device *d)
188{
189 struct mii_bus *bus = to_mii_bus(d);
190
191 WARN(bus->state != MDIOBUS_RELEASED &&
192 /* for compatibility with error handling in drivers */
193 bus->state != MDIOBUS_ALLOCATED,
194 "%s: not in RELEASED or ALLOCATED state\n",
195 bus->id);
196
197 if (bus->state == MDIOBUS_RELEASED)
198 fwnode_handle_put(dev_fwnode(d));
199
200 kfree(bus);
201}
202
203struct mdio_bus_stat_attr {
204 int addr;
205 unsigned int field_offset;
206};
207
208static u64 mdio_bus_get_stat(struct mdio_bus_stats *s, unsigned int offset)
209{
210 const char *p = (const char *)s + offset;
211 unsigned int start;
212 u64 val = 0;
213
214 do {
215 start = u64_stats_fetch_begin(&s->syncp);
216 val = u64_stats_read((const u64_stats_t *)p);
217 } while (u64_stats_fetch_retry(&s->syncp, start));
218
219 return val;
220}
221
222static u64 mdio_bus_get_global_stat(struct mii_bus *bus, unsigned int offset)
223{
224 unsigned int i;
225 u64 val = 0;
226
227 for (i = 0; i < PHY_MAX_ADDR; i++)
228 val += mdio_bus_get_stat(&bus->stats[i], offset);
229
230 return val;
231}
232
233static ssize_t mdio_bus_stat_field_show(struct device *dev,
234 struct device_attribute *attr,
235 char *buf)
236{
237 struct mii_bus *bus = to_mii_bus(dev);
238 struct mdio_bus_stat_attr *sattr;
239 struct dev_ext_attribute *eattr;
240 u64 val;
241
242 eattr = container_of(attr, struct dev_ext_attribute, attr);
243 sattr = eattr->var;
244
245 if (sattr->addr < 0)
246 val = mdio_bus_get_global_stat(bus, sattr->field_offset);
247 else
248 val = mdio_bus_get_stat(&bus->stats[sattr->addr],
249 sattr->field_offset);
250
251 return sysfs_emit(buf, "%llu\n", val);
252}
253
254static ssize_t mdio_bus_device_stat_field_show(struct device *dev,
255 struct device_attribute *attr,
256 char *buf)
257{
258 struct mdio_device *mdiodev = to_mdio_device(dev);
259 struct mii_bus *bus = mdiodev->bus;
260 struct mdio_bus_stat_attr *sattr;
261 struct dev_ext_attribute *eattr;
262 int addr = mdiodev->addr;
263 u64 val;
264
265 eattr = container_of(attr, struct dev_ext_attribute, attr);
266 sattr = eattr->var;
267
268 val = mdio_bus_get_stat(&bus->stats[addr], sattr->field_offset);
269
270 return sysfs_emit(buf, "%llu\n", val);
271}
272
273#define MDIO_BUS_STATS_ATTR_DECL(field, file) \
274static struct dev_ext_attribute dev_attr_mdio_bus_##field = { \
275 .attr = { .attr = { .name = file, .mode = 0444 }, \
276 .show = mdio_bus_stat_field_show, \
277 }, \
278 .var = &((struct mdio_bus_stat_attr) { \
279 -1, offsetof(struct mdio_bus_stats, field) \
280 }), \
281}; \
282static struct dev_ext_attribute dev_attr_mdio_bus_device_##field = { \
283 .attr = { .attr = { .name = file, .mode = 0444 }, \
284 .show = mdio_bus_device_stat_field_show, \
285 }, \
286 .var = &((struct mdio_bus_stat_attr) { \
287 -1, offsetof(struct mdio_bus_stats, field) \
288 }), \
289};
290
291#define MDIO_BUS_STATS_ATTR(field) \
292 MDIO_BUS_STATS_ATTR_DECL(field, __stringify(field))
293
294MDIO_BUS_STATS_ATTR(transfers);
295MDIO_BUS_STATS_ATTR(errors);
296MDIO_BUS_STATS_ATTR(writes);
297MDIO_BUS_STATS_ATTR(reads);
298
299#define MDIO_BUS_STATS_ADDR_ATTR_DECL(field, addr, file) \
300static struct dev_ext_attribute dev_attr_mdio_bus_addr_##field##_##addr = { \
301 .attr = { .attr = { .name = file, .mode = 0444 }, \
302 .show = mdio_bus_stat_field_show, \
303 }, \
304 .var = &((struct mdio_bus_stat_attr) { \
305 addr, offsetof(struct mdio_bus_stats, field) \
306 }), \
307}
308
309#define MDIO_BUS_STATS_ADDR_ATTR(field, addr) \
310 MDIO_BUS_STATS_ADDR_ATTR_DECL(field, addr, \
311 __stringify(field) "_" __stringify(addr))
312
313#define MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(addr) \
314 MDIO_BUS_STATS_ADDR_ATTR(transfers, addr); \
315 MDIO_BUS_STATS_ADDR_ATTR(errors, addr); \
316 MDIO_BUS_STATS_ADDR_ATTR(writes, addr); \
317 MDIO_BUS_STATS_ADDR_ATTR(reads, addr) \
318
319MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(0);
320MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(1);
321MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(2);
322MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(3);
323MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(4);
324MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(5);
325MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(6);
326MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(7);
327MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(8);
328MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(9);
329MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(10);
330MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(11);
331MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(12);
332MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(13);
333MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(14);
334MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(15);
335MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(16);
336MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(17);
337MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(18);
338MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(19);
339MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(20);
340MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(21);
341MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(22);
342MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(23);
343MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(24);
344MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(25);
345MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(26);
346MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(27);
347MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(28);
348MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(29);
349MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(30);
350MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(31);
351
352#define MDIO_BUS_STATS_ADDR_ATTR_GROUP(addr) \
353 &dev_attr_mdio_bus_addr_transfers_##addr.attr.attr, \
354 &dev_attr_mdio_bus_addr_errors_##addr.attr.attr, \
355 &dev_attr_mdio_bus_addr_writes_##addr.attr.attr, \
356 &dev_attr_mdio_bus_addr_reads_##addr.attr.attr \
357
358static struct attribute *mdio_bus_statistics_attrs[] = {
359 &dev_attr_mdio_bus_transfers.attr.attr,
360 &dev_attr_mdio_bus_errors.attr.attr,
361 &dev_attr_mdio_bus_writes.attr.attr,
362 &dev_attr_mdio_bus_reads.attr.attr,
363 MDIO_BUS_STATS_ADDR_ATTR_GROUP(0),
364 MDIO_BUS_STATS_ADDR_ATTR_GROUP(1),
365 MDIO_BUS_STATS_ADDR_ATTR_GROUP(2),
366 MDIO_BUS_STATS_ADDR_ATTR_GROUP(3),
367 MDIO_BUS_STATS_ADDR_ATTR_GROUP(4),
368 MDIO_BUS_STATS_ADDR_ATTR_GROUP(5),
369 MDIO_BUS_STATS_ADDR_ATTR_GROUP(6),
370 MDIO_BUS_STATS_ADDR_ATTR_GROUP(7),
371 MDIO_BUS_STATS_ADDR_ATTR_GROUP(8),
372 MDIO_BUS_STATS_ADDR_ATTR_GROUP(9),
373 MDIO_BUS_STATS_ADDR_ATTR_GROUP(10),
374 MDIO_BUS_STATS_ADDR_ATTR_GROUP(11),
375 MDIO_BUS_STATS_ADDR_ATTR_GROUP(12),
376 MDIO_BUS_STATS_ADDR_ATTR_GROUP(13),
377 MDIO_BUS_STATS_ADDR_ATTR_GROUP(14),
378 MDIO_BUS_STATS_ADDR_ATTR_GROUP(15),
379 MDIO_BUS_STATS_ADDR_ATTR_GROUP(16),
380 MDIO_BUS_STATS_ADDR_ATTR_GROUP(17),
381 MDIO_BUS_STATS_ADDR_ATTR_GROUP(18),
382 MDIO_BUS_STATS_ADDR_ATTR_GROUP(19),
383 MDIO_BUS_STATS_ADDR_ATTR_GROUP(20),
384 MDIO_BUS_STATS_ADDR_ATTR_GROUP(21),
385 MDIO_BUS_STATS_ADDR_ATTR_GROUP(22),
386 MDIO_BUS_STATS_ADDR_ATTR_GROUP(23),
387 MDIO_BUS_STATS_ADDR_ATTR_GROUP(24),
388 MDIO_BUS_STATS_ADDR_ATTR_GROUP(25),
389 MDIO_BUS_STATS_ADDR_ATTR_GROUP(26),
390 MDIO_BUS_STATS_ADDR_ATTR_GROUP(27),
391 MDIO_BUS_STATS_ADDR_ATTR_GROUP(28),
392 MDIO_BUS_STATS_ADDR_ATTR_GROUP(29),
393 MDIO_BUS_STATS_ADDR_ATTR_GROUP(30),
394 MDIO_BUS_STATS_ADDR_ATTR_GROUP(31),
395 NULL,
396};
397
398static const struct attribute_group mdio_bus_statistics_group = {
399 .name = "statistics",
400 .attrs = mdio_bus_statistics_attrs,
401};
402
403static const struct attribute_group *mdio_bus_groups[] = {
404 &mdio_bus_statistics_group,
405 NULL,
406};
407
408static struct class mdio_bus_class = {
409 .name = "mdio_bus",
410 .dev_release = mdiobus_release,
411 .dev_groups = mdio_bus_groups,
412};
413
414/**
415 * mdio_find_bus - Given the name of a mdiobus, find the mii_bus.
416 * @mdio_name: The name of a mdiobus.
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_deviced'ed once the bus is finished with.
421 */
422struct mii_bus *mdio_find_bus(const char *mdio_name)
423{
424 struct device *d;
425
426 d = class_find_device_by_name(&mdio_bus_class, mdio_name);
427 return d ? to_mii_bus(d) : NULL;
428}
429EXPORT_SYMBOL(mdio_find_bus);
430
431#if IS_ENABLED(CONFIG_OF_MDIO)
432/**
433 * of_mdio_find_bus - Given an mii_bus node, find the mii_bus.
434 * @mdio_bus_np: Pointer to the mii_bus.
435 *
436 * Returns a reference to the mii_bus, or NULL if none found. The
437 * embedded struct device will have its reference count incremented,
438 * and this must be put once the bus is finished with.
439 *
440 * Because the association of a device_node and mii_bus is made via
441 * of_mdiobus_register(), the mii_bus cannot be found before it is
442 * registered with of_mdiobus_register().
443 *
444 */
445struct mii_bus *of_mdio_find_bus(struct device_node *mdio_bus_np)
446{
447 struct device *d;
448
449 if (!mdio_bus_np)
450 return NULL;
451
452 d = class_find_device_by_of_node(&mdio_bus_class, mdio_bus_np);
453 return d ? to_mii_bus(d) : NULL;
454}
455EXPORT_SYMBOL(of_mdio_find_bus);
456
457/* Walk the list of subnodes of a mdio bus and look for a node that
458 * matches the mdio device's address with its 'reg' property. If
459 * found, set the of_node pointer for the mdio device. This allows
460 * auto-probed phy devices to be supplied with information passed in
461 * via DT.
462 */
463static void of_mdiobus_link_mdiodev(struct mii_bus *bus,
464 struct mdio_device *mdiodev)
465{
466 struct device *dev = &mdiodev->dev;
467 struct device_node *child;
468
469 if (dev->of_node || !bus->dev.of_node)
470 return;
471
472 for_each_available_child_of_node(bus->dev.of_node, child) {
473 int addr;
474
475 addr = of_mdio_parse_addr(dev, child);
476 if (addr < 0)
477 continue;
478
479 if (addr == mdiodev->addr) {
480 device_set_node(dev, of_fwnode_handle(child));
481 /* The refcount on "child" is passed to the mdio
482 * device. Do _not_ use of_node_put(child) here.
483 */
484 return;
485 }
486 }
487}
488#else /* !IS_ENABLED(CONFIG_OF_MDIO) */
489static inline void of_mdiobus_link_mdiodev(struct mii_bus *mdio,
490 struct mdio_device *mdiodev)
491{
492}
493#endif
494
495/**
496 * mdiobus_create_device - create a full MDIO device given
497 * a mdio_board_info structure
498 * @bus: MDIO bus to create the devices on
499 * @bi: mdio_board_info structure describing the devices
500 *
501 * Returns 0 on success or < 0 on error.
502 */
503static int mdiobus_create_device(struct mii_bus *bus,
504 struct mdio_board_info *bi)
505{
506 struct mdio_device *mdiodev;
507 int ret = 0;
508
509 mdiodev = mdio_device_create(bus, bi->mdio_addr);
510 if (IS_ERR(mdiodev))
511 return -ENODEV;
512
513 strscpy(mdiodev->modalias, bi->modalias,
514 sizeof(mdiodev->modalias));
515 mdiodev->bus_match = mdio_device_bus_match;
516 mdiodev->dev.platform_data = (void *)bi->platform_data;
517
518 ret = mdio_device_register(mdiodev);
519 if (ret)
520 mdio_device_free(mdiodev);
521
522 return ret;
523}
524
525static struct phy_device *mdiobus_scan(struct mii_bus *bus, int addr, bool c45)
526{
527 struct phy_device *phydev = ERR_PTR(-ENODEV);
528 int err;
529
530 phydev = get_phy_device(bus, addr, c45);
531 if (IS_ERR(phydev))
532 return phydev;
533
534 /* For DT, see if the auto-probed phy has a corresponding child
535 * in the bus node, and set the of_node pointer in this case.
536 */
537 of_mdiobus_link_mdiodev(bus, &phydev->mdio);
538
539 err = phy_device_register(phydev);
540 if (err) {
541 phy_device_free(phydev);
542 return ERR_PTR(-ENODEV);
543 }
544
545 return phydev;
546}
547
548/**
549 * mdiobus_scan_c22 - scan one address on a bus for C22 MDIO devices.
550 * @bus: mii_bus to scan
551 * @addr: address on bus to scan
552 *
553 * This function scans one address on the MDIO bus, looking for
554 * devices which can be identified using a vendor/product ID in
555 * registers 2 and 3. Not all MDIO devices have such registers, but
556 * PHY devices typically do. Hence this function assumes anything
557 * found is a PHY, or can be treated as a PHY. Other MDIO devices,
558 * such as switches, will probably not be found during the scan.
559 */
560struct phy_device *mdiobus_scan_c22(struct mii_bus *bus, int addr)
561{
562 return mdiobus_scan(bus, addr, false);
563}
564EXPORT_SYMBOL(mdiobus_scan_c22);
565
566/**
567 * mdiobus_scan_c45 - scan one address on a bus for C45 MDIO devices.
568 * @bus: mii_bus to scan
569 * @addr: address on bus to scan
570 *
571 * This function scans one address on the MDIO bus, looking for
572 * devices which can be identified using a vendor/product ID in
573 * registers 2 and 3. Not all MDIO devices have such registers, but
574 * PHY devices typically do. Hence this function assumes anything
575 * found is a PHY, or can be treated as a PHY. Other MDIO devices,
576 * such as switches, will probably not be found during the scan.
577 */
578static struct phy_device *mdiobus_scan_c45(struct mii_bus *bus, int addr)
579{
580 return mdiobus_scan(bus, addr, true);
581}
582
583static int mdiobus_scan_bus_c22(struct mii_bus *bus)
584{
585 int i;
586
587 for (i = 0; i < PHY_MAX_ADDR; i++) {
588 if ((bus->phy_mask & BIT(i)) == 0) {
589 struct phy_device *phydev;
590
591 phydev = mdiobus_scan_c22(bus, i);
592 if (IS_ERR(phydev) && (PTR_ERR(phydev) != -ENODEV))
593 return PTR_ERR(phydev);
594 }
595 }
596 return 0;
597}
598
599static int mdiobus_scan_bus_c45(struct mii_bus *bus)
600{
601 int i;
602
603 for (i = 0; i < PHY_MAX_ADDR; i++) {
604 if ((bus->phy_mask & BIT(i)) == 0) {
605 struct phy_device *phydev;
606
607 /* Don't scan C45 if we already have a C22 device */
608 if (bus->mdio_map[i])
609 continue;
610
611 phydev = mdiobus_scan_c45(bus, i);
612 if (IS_ERR(phydev) && (PTR_ERR(phydev) != -ENODEV))
613 return PTR_ERR(phydev);
614 }
615 }
616 return 0;
617}
618
619/* There are some C22 PHYs which do bad things when where is a C45
620 * transaction on the bus, like accepting a read themselves, and
621 * stomping over the true devices reply, to performing a write to
622 * themselves which was intended for another device. Now that C22
623 * devices have been found, see if any of them are bad for C45, and if we
624 * should skip the C45 scan.
625 */
626static bool mdiobus_prevent_c45_scan(struct mii_bus *bus)
627{
628 int i;
629
630 for (i = 0; i < PHY_MAX_ADDR; i++) {
631 struct phy_device *phydev;
632 u32 oui;
633
634 phydev = mdiobus_get_phy(bus, i);
635 if (!phydev)
636 continue;
637 oui = phydev->phy_id >> 10;
638
639 if (oui == MICREL_OUI)
640 return true;
641 }
642 return false;
643}
644
645/**
646 * __mdiobus_register - bring up all the PHYs on a given bus and attach them to bus
647 * @bus: target mii_bus
648 * @owner: module containing bus accessor functions
649 *
650 * Description: Called by a bus driver to bring up all the PHYs
651 * on a given bus, and attach them to the bus. Drivers should use
652 * mdiobus_register() rather than __mdiobus_register() unless they
653 * need to pass a specific owner module. MDIO devices which are not
654 * PHYs will not be brought up by this function. They are expected
655 * to be explicitly listed in DT and instantiated by of_mdiobus_register().
656 *
657 * Returns 0 on success or < 0 on error.
658 */
659int __mdiobus_register(struct mii_bus *bus, struct module *owner)
660{
661 struct mdio_device *mdiodev;
662 struct gpio_desc *gpiod;
663 bool prevent_c45_scan;
664 int i, err;
665
666 if (!bus || !bus->name)
667 return -EINVAL;
668
669 /* An access method always needs both read and write operations */
670 if (!!bus->read != !!bus->write || !!bus->read_c45 != !!bus->write_c45)
671 return -EINVAL;
672
673 /* At least one method is mandatory */
674 if (!bus->read && !bus->read_c45)
675 return -EINVAL;
676
677 if (bus->parent && bus->parent->of_node)
678 bus->parent->of_node->fwnode.flags |=
679 FWNODE_FLAG_NEEDS_CHILD_BOUND_ON_ADD;
680
681 WARN(bus->state != MDIOBUS_ALLOCATED &&
682 bus->state != MDIOBUS_UNREGISTERED,
683 "%s: not in ALLOCATED or UNREGISTERED state\n", bus->id);
684
685 bus->owner = owner;
686 bus->dev.parent = bus->parent;
687 bus->dev.class = &mdio_bus_class;
688 bus->dev.groups = NULL;
689 dev_set_name(&bus->dev, "%s", bus->id);
690
691 /* If the bus state is allocated, we're registering a fresh bus
692 * that may have a fwnode associated with it. Grab a reference
693 * to the fwnode. This will be dropped when the bus is released.
694 * If the bus was set to unregistered, it means that the bus was
695 * previously registered, and we've already grabbed a reference.
696 */
697 if (bus->state == MDIOBUS_ALLOCATED)
698 fwnode_handle_get(dev_fwnode(&bus->dev));
699
700 /* We need to set state to MDIOBUS_UNREGISTERED to correctly release
701 * the device in mdiobus_free()
702 *
703 * State will be updated later in this function in case of success
704 */
705 bus->state = MDIOBUS_UNREGISTERED;
706
707 err = device_register(&bus->dev);
708 if (err) {
709 pr_err("mii_bus %s failed to register\n", bus->id);
710 return -EINVAL;
711 }
712
713 mutex_init(&bus->mdio_lock);
714 mutex_init(&bus->shared_lock);
715
716 /* assert bus level PHY GPIO reset */
717 gpiod = devm_gpiod_get_optional(&bus->dev, "reset", GPIOD_OUT_HIGH);
718 if (IS_ERR(gpiod)) {
719 err = dev_err_probe(&bus->dev, PTR_ERR(gpiod),
720 "mii_bus %s couldn't get reset GPIO\n",
721 bus->id);
722 device_del(&bus->dev);
723 return err;
724 } else if (gpiod) {
725 bus->reset_gpiod = gpiod;
726 fsleep(bus->reset_delay_us);
727 gpiod_set_value_cansleep(gpiod, 0);
728 if (bus->reset_post_delay_us > 0)
729 fsleep(bus->reset_post_delay_us);
730 }
731
732 if (bus->reset) {
733 err = bus->reset(bus);
734 if (err)
735 goto error_reset_gpiod;
736 }
737
738 if (bus->read) {
739 err = mdiobus_scan_bus_c22(bus);
740 if (err)
741 goto error;
742 }
743
744 prevent_c45_scan = mdiobus_prevent_c45_scan(bus);
745
746 if (!prevent_c45_scan && bus->read_c45) {
747 err = mdiobus_scan_bus_c45(bus);
748 if (err)
749 goto error;
750 }
751
752 mdiobus_setup_mdiodev_from_board_info(bus, mdiobus_create_device);
753
754 bus->state = MDIOBUS_REGISTERED;
755 dev_dbg(&bus->dev, "probed\n");
756 return 0;
757
758error:
759 for (i = 0; i < PHY_MAX_ADDR; i++) {
760 mdiodev = bus->mdio_map[i];
761 if (!mdiodev)
762 continue;
763
764 mdiodev->device_remove(mdiodev);
765 mdiodev->device_free(mdiodev);
766 }
767error_reset_gpiod:
768 /* Put PHYs in RESET to save power */
769 if (bus->reset_gpiod)
770 gpiod_set_value_cansleep(bus->reset_gpiod, 1);
771
772 device_del(&bus->dev);
773 return err;
774}
775EXPORT_SYMBOL(__mdiobus_register);
776
777void mdiobus_unregister(struct mii_bus *bus)
778{
779 struct mdio_device *mdiodev;
780 int i;
781
782 if (WARN_ON_ONCE(bus->state != MDIOBUS_REGISTERED))
783 return;
784 bus->state = MDIOBUS_UNREGISTERED;
785
786 for (i = 0; i < PHY_MAX_ADDR; i++) {
787 mdiodev = bus->mdio_map[i];
788 if (!mdiodev)
789 continue;
790
791 if (mdiodev->reset_gpio)
792 gpiod_put(mdiodev->reset_gpio);
793
794 mdiodev->device_remove(mdiodev);
795 mdiodev->device_free(mdiodev);
796 }
797
798 /* Put PHYs in RESET to save power */
799 if (bus->reset_gpiod)
800 gpiod_set_value_cansleep(bus->reset_gpiod, 1);
801
802 device_del(&bus->dev);
803}
804EXPORT_SYMBOL(mdiobus_unregister);
805
806/**
807 * mdiobus_free - free a struct mii_bus
808 * @bus: mii_bus to free
809 *
810 * This function releases the reference to the underlying device
811 * object in the mii_bus. If this is the last reference, the mii_bus
812 * will be freed.
813 */
814void mdiobus_free(struct mii_bus *bus)
815{
816 /* For compatibility with error handling in drivers. */
817 if (bus->state == MDIOBUS_ALLOCATED) {
818 kfree(bus);
819 return;
820 }
821
822 WARN(bus->state != MDIOBUS_UNREGISTERED,
823 "%s: not in UNREGISTERED state\n", bus->id);
824 bus->state = MDIOBUS_RELEASED;
825
826 put_device(&bus->dev);
827}
828EXPORT_SYMBOL(mdiobus_free);
829
830static void mdiobus_stats_acct(struct mdio_bus_stats *stats, bool op, int ret)
831{
832 preempt_disable();
833 u64_stats_update_begin(&stats->syncp);
834
835 u64_stats_inc(&stats->transfers);
836 if (ret < 0) {
837 u64_stats_inc(&stats->errors);
838 goto out;
839 }
840
841 if (op)
842 u64_stats_inc(&stats->reads);
843 else
844 u64_stats_inc(&stats->writes);
845out:
846 u64_stats_update_end(&stats->syncp);
847 preempt_enable();
848}
849
850/**
851 * __mdiobus_read - Unlocked version of the mdiobus_read function
852 * @bus: the mii_bus struct
853 * @addr: the phy address
854 * @regnum: register number to read
855 *
856 * Read a MDIO bus register. Caller must hold the mdio bus lock.
857 *
858 * NOTE: MUST NOT be called from interrupt context.
859 */
860int __mdiobus_read(struct mii_bus *bus, int addr, u32 regnum)
861{
862 int retval;
863
864 lockdep_assert_held_once(&bus->mdio_lock);
865
866 if (bus->read)
867 retval = bus->read(bus, addr, regnum);
868 else
869 retval = -EOPNOTSUPP;
870
871 trace_mdio_access(bus, 1, addr, regnum, retval, retval);
872 mdiobus_stats_acct(&bus->stats[addr], true, retval);
873
874 return retval;
875}
876EXPORT_SYMBOL(__mdiobus_read);
877
878/**
879 * __mdiobus_write - Unlocked version of the mdiobus_write function
880 * @bus: the mii_bus struct
881 * @addr: the phy address
882 * @regnum: register number to write
883 * @val: value to write to @regnum
884 *
885 * Write a MDIO bus register. Caller must hold the mdio bus lock.
886 *
887 * NOTE: MUST NOT be called from interrupt context.
888 */
889int __mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val)
890{
891 int err;
892
893 lockdep_assert_held_once(&bus->mdio_lock);
894
895 if (bus->write)
896 err = bus->write(bus, addr, regnum, val);
897 else
898 err = -EOPNOTSUPP;
899
900 trace_mdio_access(bus, 0, addr, regnum, val, err);
901 mdiobus_stats_acct(&bus->stats[addr], false, err);
902
903 return err;
904}
905EXPORT_SYMBOL(__mdiobus_write);
906
907/**
908 * __mdiobus_modify_changed - Unlocked version of the mdiobus_modify function
909 * @bus: the mii_bus struct
910 * @addr: the phy address
911 * @regnum: register number to modify
912 * @mask: bit mask of bits to clear
913 * @set: bit mask of bits to set
914 *
915 * Read, modify, and if any change, write the register value back to the
916 * device. Any error returns a negative number.
917 *
918 * NOTE: MUST NOT be called from interrupt context.
919 */
920int __mdiobus_modify_changed(struct mii_bus *bus, int addr, u32 regnum,
921 u16 mask, u16 set)
922{
923 int new, ret;
924
925 ret = __mdiobus_read(bus, addr, regnum);
926 if (ret < 0)
927 return ret;
928
929 new = (ret & ~mask) | set;
930 if (new == ret)
931 return 0;
932
933 ret = __mdiobus_write(bus, addr, regnum, new);
934
935 return ret < 0 ? ret : 1;
936}
937EXPORT_SYMBOL_GPL(__mdiobus_modify_changed);
938
939/**
940 * __mdiobus_c45_read - Unlocked version of the mdiobus_c45_read function
941 * @bus: the mii_bus struct
942 * @addr: the phy address
943 * @devad: device address to read
944 * @regnum: register number to read
945 *
946 * Read a MDIO bus register. Caller must hold the mdio bus lock.
947 *
948 * NOTE: MUST NOT be called from interrupt context.
949 */
950int __mdiobus_c45_read(struct mii_bus *bus, int addr, int devad, u32 regnum)
951{
952 int retval;
953
954 lockdep_assert_held_once(&bus->mdio_lock);
955
956 if (bus->read_c45)
957 retval = bus->read_c45(bus, addr, devad, regnum);
958 else
959 retval = -EOPNOTSUPP;
960
961 trace_mdio_access(bus, 1, addr, regnum, retval, retval);
962 mdiobus_stats_acct(&bus->stats[addr], true, retval);
963
964 return retval;
965}
966EXPORT_SYMBOL(__mdiobus_c45_read);
967
968/**
969 * __mdiobus_c45_write - Unlocked version of the mdiobus_write function
970 * @bus: the mii_bus struct
971 * @addr: the phy address
972 * @devad: device address to read
973 * @regnum: register number to write
974 * @val: value to write to @regnum
975 *
976 * Write a MDIO bus register. Caller must hold the mdio bus lock.
977 *
978 * NOTE: MUST NOT be called from interrupt context.
979 */
980int __mdiobus_c45_write(struct mii_bus *bus, int addr, int devad, u32 regnum,
981 u16 val)
982{
983 int err;
984
985 lockdep_assert_held_once(&bus->mdio_lock);
986
987 if (bus->write_c45)
988 err = bus->write_c45(bus, addr, devad, regnum, val);
989 else
990 err = -EOPNOTSUPP;
991
992 trace_mdio_access(bus, 0, addr, regnum, val, err);
993 mdiobus_stats_acct(&bus->stats[addr], false, err);
994
995 return err;
996}
997EXPORT_SYMBOL(__mdiobus_c45_write);
998
999/**
1000 * __mdiobus_c45_modify_changed - Unlocked version of the mdiobus_modify function
1001 * @bus: the mii_bus struct
1002 * @addr: the phy address
1003 * @devad: device address to read
1004 * @regnum: register number to modify
1005 * @mask: bit mask of bits to clear
1006 * @set: bit mask of bits to set
1007 *
1008 * Read, modify, and if any change, write the register value back to the
1009 * device. Any error returns a negative number.
1010 *
1011 * NOTE: MUST NOT be called from interrupt context.
1012 */
1013static int __mdiobus_c45_modify_changed(struct mii_bus *bus, int addr,
1014 int devad, u32 regnum, u16 mask,
1015 u16 set)
1016{
1017 int new, ret;
1018
1019 ret = __mdiobus_c45_read(bus, addr, devad, regnum);
1020 if (ret < 0)
1021 return ret;
1022
1023 new = (ret & ~mask) | set;
1024 if (new == ret)
1025 return 0;
1026
1027 ret = __mdiobus_c45_write(bus, addr, devad, regnum, new);
1028
1029 return ret < 0 ? ret : 1;
1030}
1031
1032/**
1033 * mdiobus_read_nested - Nested version of the mdiobus_read function
1034 * @bus: the mii_bus struct
1035 * @addr: the phy address
1036 * @regnum: register number to read
1037 *
1038 * In case of nested MDIO bus access avoid lockdep false positives by
1039 * using mutex_lock_nested().
1040 *
1041 * NOTE: MUST NOT be called from interrupt context,
1042 * because the bus read/write functions may wait for an interrupt
1043 * to conclude the operation.
1044 */
1045int mdiobus_read_nested(struct mii_bus *bus, int addr, u32 regnum)
1046{
1047 int retval;
1048
1049 mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED);
1050 retval = __mdiobus_read(bus, addr, regnum);
1051 mutex_unlock(&bus->mdio_lock);
1052
1053 return retval;
1054}
1055EXPORT_SYMBOL(mdiobus_read_nested);
1056
1057/**
1058 * mdiobus_read - Convenience function for reading a given MII mgmt register
1059 * @bus: the mii_bus struct
1060 * @addr: the phy address
1061 * @regnum: register number to read
1062 *
1063 * NOTE: MUST NOT be called from interrupt context,
1064 * because the bus read/write functions may wait for an interrupt
1065 * to conclude the operation.
1066 */
1067int mdiobus_read(struct mii_bus *bus, int addr, u32 regnum)
1068{
1069 int retval;
1070
1071 mutex_lock(&bus->mdio_lock);
1072 retval = __mdiobus_read(bus, addr, regnum);
1073 mutex_unlock(&bus->mdio_lock);
1074
1075 return retval;
1076}
1077EXPORT_SYMBOL(mdiobus_read);
1078
1079/**
1080 * mdiobus_c45_read - Convenience function for reading a given MII mgmt register
1081 * @bus: the mii_bus struct
1082 * @addr: the phy address
1083 * @devad: device address to read
1084 * @regnum: register number to read
1085 *
1086 * NOTE: MUST NOT be called from interrupt context,
1087 * because the bus read/write functions may wait for an interrupt
1088 * to conclude the operation.
1089 */
1090int mdiobus_c45_read(struct mii_bus *bus, int addr, int devad, u32 regnum)
1091{
1092 int retval;
1093
1094 mutex_lock(&bus->mdio_lock);
1095 retval = __mdiobus_c45_read(bus, addr, devad, regnum);
1096 mutex_unlock(&bus->mdio_lock);
1097
1098 return retval;
1099}
1100EXPORT_SYMBOL(mdiobus_c45_read);
1101
1102/**
1103 * mdiobus_c45_read_nested - Nested version of the mdiobus_c45_read function
1104 * @bus: the mii_bus struct
1105 * @addr: the phy address
1106 * @devad: device address to read
1107 * @regnum: register number to read
1108 *
1109 * In case of nested MDIO bus access avoid lockdep false positives by
1110 * using mutex_lock_nested().
1111 *
1112 * NOTE: MUST NOT be called from interrupt context,
1113 * because the bus read/write functions may wait for an interrupt
1114 * to conclude the operation.
1115 */
1116int mdiobus_c45_read_nested(struct mii_bus *bus, int addr, int devad,
1117 u32 regnum)
1118{
1119 int retval;
1120
1121 mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED);
1122 retval = __mdiobus_c45_read(bus, addr, devad, regnum);
1123 mutex_unlock(&bus->mdio_lock);
1124
1125 return retval;
1126}
1127EXPORT_SYMBOL(mdiobus_c45_read_nested);
1128
1129/**
1130 * mdiobus_write_nested - Nested version of the mdiobus_write function
1131 * @bus: the mii_bus struct
1132 * @addr: the phy address
1133 * @regnum: register number to write
1134 * @val: value to write to @regnum
1135 *
1136 * In case of nested MDIO bus access avoid lockdep false positives by
1137 * using mutex_lock_nested().
1138 *
1139 * NOTE: MUST NOT be called from interrupt context,
1140 * because the bus read/write functions may wait for an interrupt
1141 * to conclude the operation.
1142 */
1143int mdiobus_write_nested(struct mii_bus *bus, int addr, u32 regnum, u16 val)
1144{
1145 int err;
1146
1147 mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED);
1148 err = __mdiobus_write(bus, addr, regnum, val);
1149 mutex_unlock(&bus->mdio_lock);
1150
1151 return err;
1152}
1153EXPORT_SYMBOL(mdiobus_write_nested);
1154
1155/**
1156 * mdiobus_write - Convenience function for writing a given MII mgmt register
1157 * @bus: the mii_bus struct
1158 * @addr: the phy address
1159 * @regnum: register number to write
1160 * @val: value to write to @regnum
1161 *
1162 * NOTE: MUST NOT be called from interrupt context,
1163 * because the bus read/write functions may wait for an interrupt
1164 * to conclude the operation.
1165 */
1166int mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val)
1167{
1168 int err;
1169
1170 mutex_lock(&bus->mdio_lock);
1171 err = __mdiobus_write(bus, addr, regnum, val);
1172 mutex_unlock(&bus->mdio_lock);
1173
1174 return err;
1175}
1176EXPORT_SYMBOL(mdiobus_write);
1177
1178/**
1179 * mdiobus_c45_write - Convenience function for writing a given MII mgmt register
1180 * @bus: the mii_bus struct
1181 * @addr: the phy address
1182 * @devad: device address to read
1183 * @regnum: register number to write
1184 * @val: value to write to @regnum
1185 *
1186 * NOTE: MUST NOT be called from interrupt context,
1187 * because the bus read/write functions may wait for an interrupt
1188 * to conclude the operation.
1189 */
1190int mdiobus_c45_write(struct mii_bus *bus, int addr, int devad, u32 regnum,
1191 u16 val)
1192{
1193 int err;
1194
1195 mutex_lock(&bus->mdio_lock);
1196 err = __mdiobus_c45_write(bus, addr, devad, regnum, val);
1197 mutex_unlock(&bus->mdio_lock);
1198
1199 return err;
1200}
1201EXPORT_SYMBOL(mdiobus_c45_write);
1202
1203/**
1204 * mdiobus_c45_write_nested - Nested version of the mdiobus_c45_write function
1205 * @bus: the mii_bus struct
1206 * @addr: the phy address
1207 * @devad: device address to read
1208 * @regnum: register number to write
1209 * @val: value to write to @regnum
1210 *
1211 * In case of nested MDIO bus access avoid lockdep false positives by
1212 * using mutex_lock_nested().
1213 *
1214 * NOTE: MUST NOT be called from interrupt context,
1215 * because the bus read/write functions may wait for an interrupt
1216 * to conclude the operation.
1217 */
1218int mdiobus_c45_write_nested(struct mii_bus *bus, int addr, int devad,
1219 u32 regnum, u16 val)
1220{
1221 int err;
1222
1223 mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED);
1224 err = __mdiobus_c45_write(bus, addr, devad, regnum, val);
1225 mutex_unlock(&bus->mdio_lock);
1226
1227 return err;
1228}
1229EXPORT_SYMBOL(mdiobus_c45_write_nested);
1230
1231/*
1232 * __mdiobus_modify - Convenience function for modifying a given mdio device
1233 * register
1234 * @bus: the mii_bus struct
1235 * @addr: the phy address
1236 * @regnum: register number to write
1237 * @mask: bit mask of bits to clear
1238 * @set: bit mask of bits to set
1239 */
1240int __mdiobus_modify(struct mii_bus *bus, int addr, u32 regnum, u16 mask,
1241 u16 set)
1242{
1243 int err;
1244
1245 err = __mdiobus_modify_changed(bus, addr, regnum, mask, set);
1246
1247 return err < 0 ? err : 0;
1248}
1249EXPORT_SYMBOL_GPL(__mdiobus_modify);
1250
1251/**
1252 * mdiobus_modify - Convenience function for modifying a given mdio device
1253 * register
1254 * @bus: the mii_bus struct
1255 * @addr: the phy address
1256 * @regnum: register number to write
1257 * @mask: bit mask of bits to clear
1258 * @set: bit mask of bits to set
1259 */
1260int mdiobus_modify(struct mii_bus *bus, int addr, u32 regnum, u16 mask, u16 set)
1261{
1262 int err;
1263
1264 mutex_lock(&bus->mdio_lock);
1265 err = __mdiobus_modify(bus, addr, regnum, mask, set);
1266 mutex_unlock(&bus->mdio_lock);
1267
1268 return err;
1269}
1270EXPORT_SYMBOL_GPL(mdiobus_modify);
1271
1272/**
1273 * mdiobus_c45_modify - Convenience function for modifying a given mdio device
1274 * register
1275 * @bus: the mii_bus struct
1276 * @addr: the phy address
1277 * @devad: device address to read
1278 * @regnum: register number to write
1279 * @mask: bit mask of bits to clear
1280 * @set: bit mask of bits to set
1281 */
1282int mdiobus_c45_modify(struct mii_bus *bus, int addr, int devad, u32 regnum,
1283 u16 mask, u16 set)
1284{
1285 int err;
1286
1287 mutex_lock(&bus->mdio_lock);
1288 err = __mdiobus_c45_modify_changed(bus, addr, devad, regnum,
1289 mask, set);
1290 mutex_unlock(&bus->mdio_lock);
1291
1292 return err < 0 ? err : 0;
1293}
1294EXPORT_SYMBOL_GPL(mdiobus_c45_modify);
1295
1296/**
1297 * mdiobus_modify_changed - Convenience function for modifying a given mdio
1298 * device register and returning if it changed
1299 * @bus: the mii_bus struct
1300 * @addr: the phy address
1301 * @regnum: register number to write
1302 * @mask: bit mask of bits to clear
1303 * @set: bit mask of bits to set
1304 */
1305int mdiobus_modify_changed(struct mii_bus *bus, int addr, u32 regnum,
1306 u16 mask, u16 set)
1307{
1308 int err;
1309
1310 mutex_lock(&bus->mdio_lock);
1311 err = __mdiobus_modify_changed(bus, addr, regnum, mask, set);
1312 mutex_unlock(&bus->mdio_lock);
1313
1314 return err;
1315}
1316EXPORT_SYMBOL_GPL(mdiobus_modify_changed);
1317
1318/**
1319 * mdiobus_c45_modify_changed - Convenience function for modifying a given mdio
1320 * device register and returning if it changed
1321 * @bus: the mii_bus struct
1322 * @addr: the phy address
1323 * @devad: device address to read
1324 * @regnum: register number to write
1325 * @mask: bit mask of bits to clear
1326 * @set: bit mask of bits to set
1327 */
1328int mdiobus_c45_modify_changed(struct mii_bus *bus, int addr, int devad,
1329 u32 regnum, u16 mask, u16 set)
1330{
1331 int err;
1332
1333 mutex_lock(&bus->mdio_lock);
1334 err = __mdiobus_c45_modify_changed(bus, addr, devad, regnum, mask, set);
1335 mutex_unlock(&bus->mdio_lock);
1336
1337 return err;
1338}
1339EXPORT_SYMBOL_GPL(mdiobus_c45_modify_changed);
1340
1341/**
1342 * mdio_bus_match - determine if given MDIO driver supports the given
1343 * MDIO device
1344 * @dev: target MDIO device
1345 * @drv: given MDIO driver
1346 *
1347 * Description: Given a MDIO device, and a MDIO driver, return 1 if
1348 * the driver supports the device. Otherwise, return 0. This may
1349 * require calling the devices own match function, since different classes
1350 * of MDIO devices have different match criteria.
1351 */
1352static int mdio_bus_match(struct device *dev, struct device_driver *drv)
1353{
1354 struct mdio_driver *mdiodrv = to_mdio_driver(drv);
1355 struct mdio_device *mdio = to_mdio_device(dev);
1356
1357 /* Both the driver and device must type-match */
1358 if (!(mdiodrv->mdiodrv.flags & MDIO_DEVICE_IS_PHY) !=
1359 !(mdio->flags & MDIO_DEVICE_FLAG_PHY))
1360 return 0;
1361
1362 if (of_driver_match_device(dev, drv))
1363 return 1;
1364
1365 if (mdio->bus_match)
1366 return mdio->bus_match(dev, drv);
1367
1368 return 0;
1369}
1370
1371static int mdio_uevent(const struct device *dev, struct kobj_uevent_env *env)
1372{
1373 int rc;
1374
1375 /* Some devices have extra OF data and an OF-style MODALIAS */
1376 rc = of_device_uevent_modalias(dev, env);
1377 if (rc != -ENODEV)
1378 return rc;
1379
1380 return 0;
1381}
1382
1383static struct attribute *mdio_bus_device_statistics_attrs[] = {
1384 &dev_attr_mdio_bus_device_transfers.attr.attr,
1385 &dev_attr_mdio_bus_device_errors.attr.attr,
1386 &dev_attr_mdio_bus_device_writes.attr.attr,
1387 &dev_attr_mdio_bus_device_reads.attr.attr,
1388 NULL,
1389};
1390
1391static const struct attribute_group mdio_bus_device_statistics_group = {
1392 .name = "statistics",
1393 .attrs = mdio_bus_device_statistics_attrs,
1394};
1395
1396static const struct attribute_group *mdio_bus_dev_groups[] = {
1397 &mdio_bus_device_statistics_group,
1398 NULL,
1399};
1400
1401struct bus_type mdio_bus_type = {
1402 .name = "mdio_bus",
1403 .dev_groups = mdio_bus_dev_groups,
1404 .match = mdio_bus_match,
1405 .uevent = mdio_uevent,
1406};
1407EXPORT_SYMBOL(mdio_bus_type);
1408
1409int __init mdio_bus_init(void)
1410{
1411 int ret;
1412
1413 ret = class_register(&mdio_bus_class);
1414 if (!ret) {
1415 ret = bus_register(&mdio_bus_type);
1416 if (ret)
1417 class_unregister(&mdio_bus_class);
1418 }
1419
1420 return ret;
1421}
1422
1423#if IS_ENABLED(CONFIG_PHYLIB)
1424void mdio_bus_exit(void)
1425{
1426 class_unregister(&mdio_bus_class);
1427 bus_unregister(&mdio_bus_type);
1428}
1429EXPORT_SYMBOL_GPL(mdio_bus_exit);
1430#else
1431module_init(mdio_bus_init);
1432/* no module_exit, intentional */
1433MODULE_LICENSE("GPL");
1434MODULE_DESCRIPTION("MDIO bus/device layer");
1435#endif
1/* MDIO Bus interface
2 *
3 * Author: Andy Fleming
4 *
5 * Copyright (c) 2004 Freescale Semiconductor, Inc.
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License as published by the
9 * Free Software Foundation; either version 2 of the License, or (at your
10 * option) any later version.
11 *
12 */
13
14#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
15
16#include <linux/kernel.h>
17#include <linux/string.h>
18#include <linux/errno.h>
19#include <linux/unistd.h>
20#include <linux/slab.h>
21#include <linux/interrupt.h>
22#include <linux/init.h>
23#include <linux/delay.h>
24#include <linux/device.h>
25#include <linux/of_device.h>
26#include <linux/of_mdio.h>
27#include <linux/netdevice.h>
28#include <linux/etherdevice.h>
29#include <linux/skbuff.h>
30#include <linux/spinlock.h>
31#include <linux/mm.h>
32#include <linux/module.h>
33#include <linux/mii.h>
34#include <linux/ethtool.h>
35#include <linux/phy.h>
36#include <linux/io.h>
37#include <linux/uaccess.h>
38
39#include <asm/irq.h>
40
41int mdiobus_register_device(struct mdio_device *mdiodev)
42{
43 if (mdiodev->bus->mdio_map[mdiodev->addr])
44 return -EBUSY;
45
46 mdiodev->bus->mdio_map[mdiodev->addr] = mdiodev;
47
48 return 0;
49}
50EXPORT_SYMBOL(mdiobus_register_device);
51
52int mdiobus_unregister_device(struct mdio_device *mdiodev)
53{
54 if (mdiodev->bus->mdio_map[mdiodev->addr] != mdiodev)
55 return -EINVAL;
56
57 mdiodev->bus->mdio_map[mdiodev->addr] = NULL;
58
59 return 0;
60}
61EXPORT_SYMBOL(mdiobus_unregister_device);
62
63struct phy_device *mdiobus_get_phy(struct mii_bus *bus, int addr)
64{
65 struct mdio_device *mdiodev = bus->mdio_map[addr];
66
67 if (!mdiodev)
68 return NULL;
69
70 if (!(mdiodev->flags & MDIO_DEVICE_FLAG_PHY))
71 return NULL;
72
73 return container_of(mdiodev, struct phy_device, mdio);
74}
75EXPORT_SYMBOL(mdiobus_get_phy);
76
77bool mdiobus_is_registered_device(struct mii_bus *bus, int addr)
78{
79 return bus->mdio_map[addr];
80}
81EXPORT_SYMBOL(mdiobus_is_registered_device);
82
83/**
84 * mdiobus_alloc_size - allocate a mii_bus structure
85 * @size: extra amount of memory to allocate for private storage.
86 * If non-zero, then bus->priv is points to that memory.
87 *
88 * Description: called by a bus driver to allocate an mii_bus
89 * structure to fill in.
90 */
91struct mii_bus *mdiobus_alloc_size(size_t size)
92{
93 struct mii_bus *bus;
94 size_t aligned_size = ALIGN(sizeof(*bus), NETDEV_ALIGN);
95 size_t alloc_size;
96 int i;
97
98 /* If we alloc extra space, it should be aligned */
99 if (size)
100 alloc_size = aligned_size + size;
101 else
102 alloc_size = sizeof(*bus);
103
104 bus = kzalloc(alloc_size, GFP_KERNEL);
105 if (!bus)
106 return NULL;
107
108 bus->state = MDIOBUS_ALLOCATED;
109 if (size)
110 bus->priv = (void *)bus + aligned_size;
111
112 /* Initialise the interrupts to polling */
113 for (i = 0; i < PHY_MAX_ADDR; i++)
114 bus->irq[i] = PHY_POLL;
115
116 return bus;
117}
118EXPORT_SYMBOL(mdiobus_alloc_size);
119
120static void _devm_mdiobus_free(struct device *dev, void *res)
121{
122 mdiobus_free(*(struct mii_bus **)res);
123}
124
125static int devm_mdiobus_match(struct device *dev, void *res, void *data)
126{
127 struct mii_bus **r = res;
128
129 if (WARN_ON(!r || !*r))
130 return 0;
131
132 return *r == data;
133}
134
135/**
136 * devm_mdiobus_alloc_size - Resource-managed mdiobus_alloc_size()
137 * @dev: Device to allocate mii_bus for
138 * @sizeof_priv: Space to allocate for private structure.
139 *
140 * Managed mdiobus_alloc_size. mii_bus allocated with this function is
141 * automatically freed on driver detach.
142 *
143 * If an mii_bus allocated with this function needs to be freed separately,
144 * devm_mdiobus_free() must be used.
145 *
146 * RETURNS:
147 * Pointer to allocated mii_bus on success, NULL on failure.
148 */
149struct mii_bus *devm_mdiobus_alloc_size(struct device *dev, int sizeof_priv)
150{
151 struct mii_bus **ptr, *bus;
152
153 ptr = devres_alloc(_devm_mdiobus_free, sizeof(*ptr), GFP_KERNEL);
154 if (!ptr)
155 return NULL;
156
157 /* use raw alloc_dr for kmalloc caller tracing */
158 bus = mdiobus_alloc_size(sizeof_priv);
159 if (bus) {
160 *ptr = bus;
161 devres_add(dev, ptr);
162 } else {
163 devres_free(ptr);
164 }
165
166 return bus;
167}
168EXPORT_SYMBOL_GPL(devm_mdiobus_alloc_size);
169
170/**
171 * devm_mdiobus_free - Resource-managed mdiobus_free()
172 * @dev: Device this mii_bus belongs to
173 * @bus: the mii_bus associated with the device
174 *
175 * Free mii_bus allocated with devm_mdiobus_alloc_size().
176 */
177void devm_mdiobus_free(struct device *dev, struct mii_bus *bus)
178{
179 int rc;
180
181 rc = devres_release(dev, _devm_mdiobus_free,
182 devm_mdiobus_match, bus);
183 WARN_ON(rc);
184}
185EXPORT_SYMBOL_GPL(devm_mdiobus_free);
186
187/**
188 * mdiobus_release - mii_bus device release callback
189 * @d: the target struct device that contains the mii_bus
190 *
191 * Description: called when the last reference to an mii_bus is
192 * dropped, to free the underlying memory.
193 */
194static void mdiobus_release(struct device *d)
195{
196 struct mii_bus *bus = to_mii_bus(d);
197 BUG_ON(bus->state != MDIOBUS_RELEASED &&
198 /* for compatibility with error handling in drivers */
199 bus->state != MDIOBUS_ALLOCATED);
200 kfree(bus);
201}
202
203static struct class mdio_bus_class = {
204 .name = "mdio_bus",
205 .dev_release = mdiobus_release,
206};
207
208#if IS_ENABLED(CONFIG_OF_MDIO)
209/* Helper function for of_mdio_find_bus */
210static int of_mdio_bus_match(struct device *dev, const void *mdio_bus_np)
211{
212 return dev->of_node == mdio_bus_np;
213}
214/**
215 * of_mdio_find_bus - Given an mii_bus node, find the mii_bus.
216 * @mdio_bus_np: Pointer to the mii_bus.
217 *
218 * Returns a reference to the mii_bus, or NULL if none found. The
219 * embedded struct device will have its reference count incremented,
220 * and this must be put once the bus is finished with.
221 *
222 * Because the association of a device_node and mii_bus is made via
223 * of_mdiobus_register(), the mii_bus cannot be found before it is
224 * registered with of_mdiobus_register().
225 *
226 */
227struct mii_bus *of_mdio_find_bus(struct device_node *mdio_bus_np)
228{
229 struct device *d;
230
231 if (!mdio_bus_np)
232 return NULL;
233
234 d = class_find_device(&mdio_bus_class, NULL, mdio_bus_np,
235 of_mdio_bus_match);
236
237 return d ? to_mii_bus(d) : NULL;
238}
239EXPORT_SYMBOL(of_mdio_find_bus);
240
241/* Walk the list of subnodes of a mdio bus and look for a node that
242 * matches the mdio device's address with its 'reg' property. If
243 * found, set the of_node pointer for the mdio device. This allows
244 * auto-probed phy devices to be supplied with information passed in
245 * via DT.
246 */
247static void of_mdiobus_link_mdiodev(struct mii_bus *bus,
248 struct mdio_device *mdiodev)
249{
250 struct device *dev = &mdiodev->dev;
251 struct device_node *child;
252
253 if (dev->of_node || !bus->dev.of_node)
254 return;
255
256 for_each_available_child_of_node(bus->dev.of_node, child) {
257 int addr;
258 int ret;
259
260 ret = of_property_read_u32(child, "reg", &addr);
261 if (ret < 0) {
262 dev_err(dev, "%s has invalid MDIO address\n",
263 child->full_name);
264 continue;
265 }
266
267 /* A MDIO device must have a reg property in the range [0-31] */
268 if (addr >= PHY_MAX_ADDR) {
269 dev_err(dev, "%s MDIO address %i is too large\n",
270 child->full_name, addr);
271 continue;
272 }
273
274 if (addr == mdiodev->addr) {
275 dev->of_node = child;
276 return;
277 }
278 }
279}
280#else /* !IS_ENABLED(CONFIG_OF_MDIO) */
281static inline void of_mdiobus_link_mdiodev(struct mii_bus *mdio,
282 struct mdio_device *mdiodev)
283{
284}
285#endif
286
287/**
288 * __mdiobus_register - bring up all the PHYs on a given bus and attach them to bus
289 * @bus: target mii_bus
290 * @owner: module containing bus accessor functions
291 *
292 * Description: Called by a bus driver to bring up all the PHYs
293 * on a given bus, and attach them to the bus. Drivers should use
294 * mdiobus_register() rather than __mdiobus_register() unless they
295 * need to pass a specific owner module. MDIO devices which are not
296 * PHYs will not be brought up by this function. They are expected to
297 * to be explicitly listed in DT and instantiated by of_mdiobus_register().
298 *
299 * Returns 0 on success or < 0 on error.
300 */
301int __mdiobus_register(struct mii_bus *bus, struct module *owner)
302{
303 struct mdio_device *mdiodev;
304 int i, err;
305
306 if (NULL == bus || NULL == bus->name ||
307 NULL == bus->read || NULL == bus->write)
308 return -EINVAL;
309
310 BUG_ON(bus->state != MDIOBUS_ALLOCATED &&
311 bus->state != MDIOBUS_UNREGISTERED);
312
313 bus->owner = owner;
314 bus->dev.parent = bus->parent;
315 bus->dev.class = &mdio_bus_class;
316 bus->dev.groups = NULL;
317 dev_set_name(&bus->dev, "%s", bus->id);
318
319 err = device_register(&bus->dev);
320 if (err) {
321 pr_err("mii_bus %s failed to register\n", bus->id);
322 put_device(&bus->dev);
323 return -EINVAL;
324 }
325
326 mutex_init(&bus->mdio_lock);
327
328 if (bus->reset)
329 bus->reset(bus);
330
331 for (i = 0; i < PHY_MAX_ADDR; i++) {
332 if ((bus->phy_mask & (1 << i)) == 0) {
333 struct phy_device *phydev;
334
335 phydev = mdiobus_scan(bus, i);
336 if (IS_ERR(phydev)) {
337 err = PTR_ERR(phydev);
338 goto error;
339 }
340 }
341 }
342
343 bus->state = MDIOBUS_REGISTERED;
344 pr_info("%s: probed\n", bus->name);
345 return 0;
346
347error:
348 while (--i >= 0) {
349 mdiodev = bus->mdio_map[i];
350 if (!mdiodev)
351 continue;
352
353 mdiodev->device_remove(mdiodev);
354 mdiodev->device_free(mdiodev);
355 }
356 device_del(&bus->dev);
357 return err;
358}
359EXPORT_SYMBOL(__mdiobus_register);
360
361void mdiobus_unregister(struct mii_bus *bus)
362{
363 struct mdio_device *mdiodev;
364 int i;
365
366 BUG_ON(bus->state != MDIOBUS_REGISTERED);
367 bus->state = MDIOBUS_UNREGISTERED;
368
369 for (i = 0; i < PHY_MAX_ADDR; i++) {
370 mdiodev = bus->mdio_map[i];
371 if (!mdiodev)
372 continue;
373
374 mdiodev->device_remove(mdiodev);
375 mdiodev->device_free(mdiodev);
376 }
377 device_del(&bus->dev);
378}
379EXPORT_SYMBOL(mdiobus_unregister);
380
381/**
382 * mdiobus_free - free a struct mii_bus
383 * @bus: mii_bus to free
384 *
385 * This function releases the reference to the underlying device
386 * object in the mii_bus. If this is the last reference, the mii_bus
387 * will be freed.
388 */
389void mdiobus_free(struct mii_bus *bus)
390{
391 /* For compatibility with error handling in drivers. */
392 if (bus->state == MDIOBUS_ALLOCATED) {
393 kfree(bus);
394 return;
395 }
396
397 BUG_ON(bus->state != MDIOBUS_UNREGISTERED);
398 bus->state = MDIOBUS_RELEASED;
399
400 put_device(&bus->dev);
401}
402EXPORT_SYMBOL(mdiobus_free);
403
404/**
405 * mdiobus_scan - scan a bus for MDIO devices.
406 * @bus: mii_bus to scan
407 * @addr: address on bus to scan
408 *
409 * This function scans the MDIO bus, looking for devices which can be
410 * identified using a vendor/product ID in registers 2 and 3. Not all
411 * MDIO devices have such registers, but PHY devices typically
412 * do. Hence this function assumes anything found is a PHY, or can be
413 * treated as a PHY. Other MDIO devices, such as switches, will
414 * probably not be found during the scan.
415 */
416struct phy_device *mdiobus_scan(struct mii_bus *bus, int addr)
417{
418 struct phy_device *phydev;
419 int err;
420
421 phydev = get_phy_device(bus, addr, false);
422 if (IS_ERR(phydev) || phydev == NULL)
423 return phydev;
424
425 /*
426 * For DT, see if the auto-probed phy has a correspoding child
427 * in the bus node, and set the of_node pointer in this case.
428 */
429 of_mdiobus_link_mdiodev(bus, &phydev->mdio);
430
431 err = phy_device_register(phydev);
432 if (err) {
433 phy_device_free(phydev);
434 return NULL;
435 }
436
437 return phydev;
438}
439EXPORT_SYMBOL(mdiobus_scan);
440
441/**
442 * mdiobus_read_nested - Nested version of the mdiobus_read function
443 * @bus: the mii_bus struct
444 * @addr: the phy address
445 * @regnum: register number to read
446 *
447 * In case of nested MDIO bus access avoid lockdep false positives by
448 * using mutex_lock_nested().
449 *
450 * NOTE: MUST NOT be called from interrupt context,
451 * because the bus read/write functions may wait for an interrupt
452 * to conclude the operation.
453 */
454int mdiobus_read_nested(struct mii_bus *bus, int addr, u32 regnum)
455{
456 int retval;
457
458 BUG_ON(in_interrupt());
459
460 mutex_lock_nested(&bus->mdio_lock, SINGLE_DEPTH_NESTING);
461 retval = bus->read(bus, addr, regnum);
462 mutex_unlock(&bus->mdio_lock);
463
464 return retval;
465}
466EXPORT_SYMBOL(mdiobus_read_nested);
467
468/**
469 * mdiobus_read - Convenience function for reading a given MII mgmt register
470 * @bus: the mii_bus struct
471 * @addr: the phy address
472 * @regnum: register number to read
473 *
474 * NOTE: MUST NOT be called from interrupt context,
475 * because the bus read/write functions may wait for an interrupt
476 * to conclude the operation.
477 */
478int mdiobus_read(struct mii_bus *bus, int addr, u32 regnum)
479{
480 int retval;
481
482 BUG_ON(in_interrupt());
483
484 mutex_lock(&bus->mdio_lock);
485 retval = bus->read(bus, addr, regnum);
486 mutex_unlock(&bus->mdio_lock);
487
488 return retval;
489}
490EXPORT_SYMBOL(mdiobus_read);
491
492/**
493 * mdiobus_write_nested - Nested version of the mdiobus_write function
494 * @bus: the mii_bus struct
495 * @addr: the phy address
496 * @regnum: register number to write
497 * @val: value to write to @regnum
498 *
499 * In case of nested MDIO bus access avoid lockdep false positives by
500 * using mutex_lock_nested().
501 *
502 * NOTE: MUST NOT be called from interrupt context,
503 * because the bus read/write functions may wait for an interrupt
504 * to conclude the operation.
505 */
506int mdiobus_write_nested(struct mii_bus *bus, int addr, u32 regnum, u16 val)
507{
508 int err;
509
510 BUG_ON(in_interrupt());
511
512 mutex_lock_nested(&bus->mdio_lock, SINGLE_DEPTH_NESTING);
513 err = bus->write(bus, addr, regnum, val);
514 mutex_unlock(&bus->mdio_lock);
515
516 return err;
517}
518EXPORT_SYMBOL(mdiobus_write_nested);
519
520/**
521 * mdiobus_write - Convenience function for writing a given MII mgmt register
522 * @bus: the mii_bus struct
523 * @addr: the phy address
524 * @regnum: register number to write
525 * @val: value to write to @regnum
526 *
527 * NOTE: MUST NOT be called from interrupt context,
528 * because the bus read/write functions may wait for an interrupt
529 * to conclude the operation.
530 */
531int mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val)
532{
533 int err;
534
535 BUG_ON(in_interrupt());
536
537 mutex_lock(&bus->mdio_lock);
538 err = bus->write(bus, addr, regnum, val);
539 mutex_unlock(&bus->mdio_lock);
540
541 return err;
542}
543EXPORT_SYMBOL(mdiobus_write);
544
545/**
546 * mdio_bus_match - determine if given MDIO driver supports the given
547 * MDIO device
548 * @dev: target MDIO device
549 * @drv: given MDIO driver
550 *
551 * Description: Given a MDIO device, and a MDIO driver, return 1 if
552 * the driver supports the device. Otherwise, return 0. This may
553 * require calling the devices own match function, since different classes
554 * of MDIO devices have different match criteria.
555 */
556static int mdio_bus_match(struct device *dev, struct device_driver *drv)
557{
558 struct mdio_device *mdio = to_mdio_device(dev);
559
560 if (of_driver_match_device(dev, drv))
561 return 1;
562
563 if (mdio->bus_match)
564 return mdio->bus_match(dev, drv);
565
566 return 0;
567}
568
569#ifdef CONFIG_PM
570static int mdio_bus_suspend(struct device *dev)
571{
572 struct mdio_device *mdio = to_mdio_device(dev);
573
574 if (mdio->pm_ops && mdio->pm_ops->suspend)
575 return mdio->pm_ops->suspend(dev);
576
577 return 0;
578}
579
580static int mdio_bus_resume(struct device *dev)
581{
582 struct mdio_device *mdio = to_mdio_device(dev);
583
584 if (mdio->pm_ops && mdio->pm_ops->resume)
585 return mdio->pm_ops->resume(dev);
586
587 return 0;
588}
589
590static int mdio_bus_restore(struct device *dev)
591{
592 struct mdio_device *mdio = to_mdio_device(dev);
593
594 if (mdio->pm_ops && mdio->pm_ops->restore)
595 return mdio->pm_ops->restore(dev);
596
597 return 0;
598}
599
600static const struct dev_pm_ops mdio_bus_pm_ops = {
601 .suspend = mdio_bus_suspend,
602 .resume = mdio_bus_resume,
603 .freeze = mdio_bus_suspend,
604 .thaw = mdio_bus_resume,
605 .restore = mdio_bus_restore,
606};
607
608#define MDIO_BUS_PM_OPS (&mdio_bus_pm_ops)
609
610#else
611
612#define MDIO_BUS_PM_OPS NULL
613
614#endif /* CONFIG_PM */
615
616struct bus_type mdio_bus_type = {
617 .name = "mdio_bus",
618 .match = mdio_bus_match,
619 .pm = MDIO_BUS_PM_OPS,
620};
621EXPORT_SYMBOL(mdio_bus_type);
622
623int __init mdio_bus_init(void)
624{
625 int ret;
626
627 ret = class_register(&mdio_bus_class);
628 if (!ret) {
629 ret = bus_register(&mdio_bus_type);
630 if (ret)
631 class_unregister(&mdio_bus_class);
632 }
633
634 return ret;
635}
636
637void mdio_bus_exit(void)
638{
639 class_unregister(&mdio_bus_class);
640 bus_unregister(&mdio_bus_type);
641}