1 // SPDX-License-Identifier: GPL-2.0+
6 * Copyright (c) 2004 Freescale Semiconductor, Inc.
9 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
11 #include <linux/kernel.h>
12 #include <linux/string.h>
13 #include <linux/errno.h>
14 #include <linux/unistd.h>
15 #include <linux/slab.h>
16 #include <linux/interrupt.h>
17 #include <linux/init.h>
18 #include <linux/delay.h>
19 #include <linux/device.h>
20 #include <linux/gpio.h>
21 #include <linux/gpio/consumer.h>
22 #include <linux/of_device.h>
23 #include <linux/of_mdio.h>
24 #include <linux/of_gpio.h>
25 #include <linux/netdevice.h>
26 #include <linux/etherdevice.h>
27 #include <linux/reset.h>
28 #include <linux/skbuff.h>
29 #include <linux/spinlock.h>
31 #include <linux/module.h>
32 #include <linux/mii.h>
33 #include <linux/ethtool.h>
34 #include <linux/phy.h>
36 #include <linux/uaccess.h>
38 #define CREATE_TRACE_POINTS
39 #include <trace/events/mdio.h>
41 #include "mdio-boardinfo.h"
43 static int mdiobus_register_gpiod(struct mdio_device *mdiodev)
47 /* Deassert the optional reset signal */
48 mdiodev->reset_gpio = gpiod_get_optional(&mdiodev->dev,
49 "reset", GPIOD_OUT_LOW);
50 error = PTR_ERR_OR_ZERO(mdiodev->reset_gpio);
54 if (mdiodev->reset_gpio)
55 gpiod_set_consumer_name(mdiodev->reset_gpio, "PHY reset");
60 static int mdiobus_register_reset(struct mdio_device *mdiodev)
62 struct reset_control *reset;
64 reset = reset_control_get_optional_exclusive(&mdiodev->dev, "phy");
66 return PTR_ERR(reset);
68 mdiodev->reset_ctrl = reset;
73 int mdiobus_register_device(struct mdio_device *mdiodev)
77 if (mdiodev->bus->mdio_map[mdiodev->addr])
80 if (mdiodev->flags & MDIO_DEVICE_FLAG_PHY) {
81 err = mdiobus_register_gpiod(mdiodev);
85 err = mdiobus_register_reset(mdiodev);
89 /* Assert the reset signal */
90 mdio_device_reset(mdiodev, 1);
93 mdiodev->bus->mdio_map[mdiodev->addr] = mdiodev;
97 EXPORT_SYMBOL(mdiobus_register_device);
99 int mdiobus_unregister_device(struct mdio_device *mdiodev)
101 if (mdiodev->bus->mdio_map[mdiodev->addr] != mdiodev)
104 reset_control_put(mdiodev->reset_ctrl);
106 mdiodev->bus->mdio_map[mdiodev->addr] = NULL;
110 EXPORT_SYMBOL(mdiobus_unregister_device);
112 struct phy_device *mdiobus_get_phy(struct mii_bus *bus, int addr)
114 struct mdio_device *mdiodev = bus->mdio_map[addr];
119 if (!(mdiodev->flags & MDIO_DEVICE_FLAG_PHY))
122 return container_of(mdiodev, struct phy_device, mdio);
124 EXPORT_SYMBOL(mdiobus_get_phy);
126 bool mdiobus_is_registered_device(struct mii_bus *bus, int addr)
128 return bus->mdio_map[addr];
130 EXPORT_SYMBOL(mdiobus_is_registered_device);
133 * mdiobus_alloc_size - allocate a mii_bus structure
134 * @size: extra amount of memory to allocate for private storage.
135 * If non-zero, then bus->priv is points to that memory.
137 * Description: called by a bus driver to allocate an mii_bus
138 * structure to fill in.
140 struct mii_bus *mdiobus_alloc_size(size_t size)
143 size_t aligned_size = ALIGN(sizeof(*bus), NETDEV_ALIGN);
147 /* If we alloc extra space, it should be aligned */
149 alloc_size = aligned_size + size;
151 alloc_size = sizeof(*bus);
153 bus = kzalloc(alloc_size, GFP_KERNEL);
157 bus->state = MDIOBUS_ALLOCATED;
159 bus->priv = (void *)bus + aligned_size;
161 /* Initialise the interrupts to polling and 64-bit seqcounts */
162 for (i = 0; i < PHY_MAX_ADDR; i++) {
163 bus->irq[i] = PHY_POLL;
164 u64_stats_init(&bus->stats[i].syncp);
169 EXPORT_SYMBOL(mdiobus_alloc_size);
171 static void _devm_mdiobus_free(struct device *dev, void *res)
173 mdiobus_free(*(struct mii_bus **)res);
176 static int devm_mdiobus_match(struct device *dev, void *res, void *data)
178 struct mii_bus **r = res;
180 if (WARN_ON(!r || !*r))
187 * devm_mdiobus_alloc_size - Resource-managed mdiobus_alloc_size()
188 * @dev: Device to allocate mii_bus for
189 * @sizeof_priv: Space to allocate for private structure.
191 * Managed mdiobus_alloc_size. mii_bus allocated with this function is
192 * automatically freed on driver detach.
194 * If an mii_bus allocated with this function needs to be freed separately,
195 * devm_mdiobus_free() must be used.
198 * Pointer to allocated mii_bus on success, NULL on failure.
200 struct mii_bus *devm_mdiobus_alloc_size(struct device *dev, int sizeof_priv)
202 struct mii_bus **ptr, *bus;
204 ptr = devres_alloc(_devm_mdiobus_free, sizeof(*ptr), GFP_KERNEL);
208 /* use raw alloc_dr for kmalloc caller tracing */
209 bus = mdiobus_alloc_size(sizeof_priv);
212 devres_add(dev, ptr);
219 EXPORT_SYMBOL_GPL(devm_mdiobus_alloc_size);
222 * devm_mdiobus_free - Resource-managed mdiobus_free()
223 * @dev: Device this mii_bus belongs to
224 * @bus: the mii_bus associated with the device
226 * Free mii_bus allocated with devm_mdiobus_alloc_size().
228 void devm_mdiobus_free(struct device *dev, struct mii_bus *bus)
232 rc = devres_release(dev, _devm_mdiobus_free,
233 devm_mdiobus_match, bus);
236 EXPORT_SYMBOL_GPL(devm_mdiobus_free);
239 * mdiobus_release - mii_bus device release callback
240 * @d: the target struct device that contains the mii_bus
242 * Description: called when the last reference to an mii_bus is
243 * dropped, to free the underlying memory.
245 static void mdiobus_release(struct device *d)
247 struct mii_bus *bus = to_mii_bus(d);
248 BUG_ON(bus->state != MDIOBUS_RELEASED &&
249 /* for compatibility with error handling in drivers */
250 bus->state != MDIOBUS_ALLOCATED);
254 struct mdio_bus_stat_attr {
256 unsigned int field_offset;
259 static u64 mdio_bus_get_stat(struct mdio_bus_stats *s, unsigned int offset)
261 const char *p = (const char *)s + offset;
266 start = u64_stats_fetch_begin(&s->syncp);
267 val = u64_stats_read((const u64_stats_t *)p);
268 } while (u64_stats_fetch_retry(&s->syncp, start));
273 static u64 mdio_bus_get_global_stat(struct mii_bus *bus, unsigned int offset)
278 for (i = 0; i < PHY_MAX_ADDR; i++)
279 val += mdio_bus_get_stat(&bus->stats[i], offset);
284 static ssize_t mdio_bus_stat_field_show(struct device *dev,
285 struct device_attribute *attr,
288 struct mii_bus *bus = to_mii_bus(dev);
289 struct mdio_bus_stat_attr *sattr;
290 struct dev_ext_attribute *eattr;
293 eattr = container_of(attr, struct dev_ext_attribute, attr);
297 val = mdio_bus_get_global_stat(bus, sattr->field_offset);
299 val = mdio_bus_get_stat(&bus->stats[sattr->addr],
300 sattr->field_offset);
302 return sprintf(buf, "%llu\n", val);
305 static ssize_t mdio_bus_device_stat_field_show(struct device *dev,
306 struct device_attribute *attr,
309 struct mdio_device *mdiodev = to_mdio_device(dev);
310 struct mii_bus *bus = mdiodev->bus;
311 struct mdio_bus_stat_attr *sattr;
312 struct dev_ext_attribute *eattr;
313 int addr = mdiodev->addr;
316 eattr = container_of(attr, struct dev_ext_attribute, attr);
319 val = mdio_bus_get_stat(&bus->stats[addr], sattr->field_offset);
321 return sprintf(buf, "%llu\n", val);
324 #define MDIO_BUS_STATS_ATTR_DECL(field, file) \
325 static struct dev_ext_attribute dev_attr_mdio_bus_##field = { \
326 .attr = { .attr = { .name = file, .mode = 0444 }, \
327 .show = mdio_bus_stat_field_show, \
329 .var = &((struct mdio_bus_stat_attr) { \
330 -1, offsetof(struct mdio_bus_stats, field) \
333 static struct dev_ext_attribute dev_attr_mdio_bus_device_##field = { \
334 .attr = { .attr = { .name = file, .mode = 0444 }, \
335 .show = mdio_bus_device_stat_field_show, \
337 .var = &((struct mdio_bus_stat_attr) { \
338 -1, offsetof(struct mdio_bus_stats, field) \
342 #define MDIO_BUS_STATS_ATTR(field) \
343 MDIO_BUS_STATS_ATTR_DECL(field, __stringify(field))
345 MDIO_BUS_STATS_ATTR(transfers);
346 MDIO_BUS_STATS_ATTR(errors);
347 MDIO_BUS_STATS_ATTR(writes);
348 MDIO_BUS_STATS_ATTR(reads);
350 #define MDIO_BUS_STATS_ADDR_ATTR_DECL(field, addr, file) \
351 static struct dev_ext_attribute dev_attr_mdio_bus_addr_##field##_##addr = { \
352 .attr = { .attr = { .name = file, .mode = 0444 }, \
353 .show = mdio_bus_stat_field_show, \
355 .var = &((struct mdio_bus_stat_attr) { \
356 addr, offsetof(struct mdio_bus_stats, field) \
360 #define MDIO_BUS_STATS_ADDR_ATTR(field, addr) \
361 MDIO_BUS_STATS_ADDR_ATTR_DECL(field, addr, \
362 __stringify(field) "_" __stringify(addr))
364 #define MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(addr) \
365 MDIO_BUS_STATS_ADDR_ATTR(transfers, addr); \
366 MDIO_BUS_STATS_ADDR_ATTR(errors, addr); \
367 MDIO_BUS_STATS_ADDR_ATTR(writes, addr); \
368 MDIO_BUS_STATS_ADDR_ATTR(reads, addr) \
370 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(0);
371 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(1);
372 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(2);
373 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(3);
374 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(4);
375 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(5);
376 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(6);
377 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(7);
378 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(8);
379 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(9);
380 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(10);
381 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(11);
382 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(12);
383 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(13);
384 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(14);
385 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(15);
386 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(16);
387 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(17);
388 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(18);
389 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(19);
390 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(20);
391 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(21);
392 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(22);
393 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(23);
394 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(24);
395 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(25);
396 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(26);
397 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(27);
398 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(28);
399 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(29);
400 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(30);
401 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(31);
403 #define MDIO_BUS_STATS_ADDR_ATTR_GROUP(addr) \
404 &dev_attr_mdio_bus_addr_transfers_##addr.attr.attr, \
405 &dev_attr_mdio_bus_addr_errors_##addr.attr.attr, \
406 &dev_attr_mdio_bus_addr_writes_##addr.attr.attr, \
407 &dev_attr_mdio_bus_addr_reads_##addr.attr.attr \
409 static struct attribute *mdio_bus_statistics_attrs[] = {
410 &dev_attr_mdio_bus_transfers.attr.attr,
411 &dev_attr_mdio_bus_errors.attr.attr,
412 &dev_attr_mdio_bus_writes.attr.attr,
413 &dev_attr_mdio_bus_reads.attr.attr,
414 MDIO_BUS_STATS_ADDR_ATTR_GROUP(0),
415 MDIO_BUS_STATS_ADDR_ATTR_GROUP(1),
416 MDIO_BUS_STATS_ADDR_ATTR_GROUP(2),
417 MDIO_BUS_STATS_ADDR_ATTR_GROUP(3),
418 MDIO_BUS_STATS_ADDR_ATTR_GROUP(4),
419 MDIO_BUS_STATS_ADDR_ATTR_GROUP(5),
420 MDIO_BUS_STATS_ADDR_ATTR_GROUP(6),
421 MDIO_BUS_STATS_ADDR_ATTR_GROUP(7),
422 MDIO_BUS_STATS_ADDR_ATTR_GROUP(8),
423 MDIO_BUS_STATS_ADDR_ATTR_GROUP(9),
424 MDIO_BUS_STATS_ADDR_ATTR_GROUP(10),
425 MDIO_BUS_STATS_ADDR_ATTR_GROUP(11),
426 MDIO_BUS_STATS_ADDR_ATTR_GROUP(12),
427 MDIO_BUS_STATS_ADDR_ATTR_GROUP(13),
428 MDIO_BUS_STATS_ADDR_ATTR_GROUP(14),
429 MDIO_BUS_STATS_ADDR_ATTR_GROUP(15),
430 MDIO_BUS_STATS_ADDR_ATTR_GROUP(16),
431 MDIO_BUS_STATS_ADDR_ATTR_GROUP(17),
432 MDIO_BUS_STATS_ADDR_ATTR_GROUP(18),
433 MDIO_BUS_STATS_ADDR_ATTR_GROUP(19),
434 MDIO_BUS_STATS_ADDR_ATTR_GROUP(20),
435 MDIO_BUS_STATS_ADDR_ATTR_GROUP(21),
436 MDIO_BUS_STATS_ADDR_ATTR_GROUP(22),
437 MDIO_BUS_STATS_ADDR_ATTR_GROUP(23),
438 MDIO_BUS_STATS_ADDR_ATTR_GROUP(24),
439 MDIO_BUS_STATS_ADDR_ATTR_GROUP(25),
440 MDIO_BUS_STATS_ADDR_ATTR_GROUP(26),
441 MDIO_BUS_STATS_ADDR_ATTR_GROUP(27),
442 MDIO_BUS_STATS_ADDR_ATTR_GROUP(28),
443 MDIO_BUS_STATS_ADDR_ATTR_GROUP(29),
444 MDIO_BUS_STATS_ADDR_ATTR_GROUP(30),
445 MDIO_BUS_STATS_ADDR_ATTR_GROUP(31),
449 static const struct attribute_group mdio_bus_statistics_group = {
450 .name = "statistics",
451 .attrs = mdio_bus_statistics_attrs,
454 static const struct attribute_group *mdio_bus_groups[] = {
455 &mdio_bus_statistics_group,
459 static struct class mdio_bus_class = {
461 .dev_release = mdiobus_release,
462 .dev_groups = mdio_bus_groups,
466 * mdio_find_bus - Given the name of a mdiobus, find the mii_bus.
467 * @mdio_bus_np: Pointer to the mii_bus.
469 * Returns a reference to the mii_bus, or NULL if none found. The
470 * embedded struct device will have its reference count incremented,
471 * and this must be put_deviced'ed once the bus is finished with.
473 struct mii_bus *mdio_find_bus(const char *mdio_name)
477 d = class_find_device_by_name(&mdio_bus_class, mdio_name);
478 return d ? to_mii_bus(d) : NULL;
480 EXPORT_SYMBOL(mdio_find_bus);
482 #if IS_ENABLED(CONFIG_OF_MDIO)
484 * of_mdio_find_bus - Given an mii_bus node, find the mii_bus.
485 * @mdio_bus_np: Pointer to the mii_bus.
487 * Returns a reference to the mii_bus, or NULL if none found. The
488 * embedded struct device will have its reference count incremented,
489 * and this must be put once the bus is finished with.
491 * Because the association of a device_node and mii_bus is made via
492 * of_mdiobus_register(), the mii_bus cannot be found before it is
493 * registered with of_mdiobus_register().
496 struct mii_bus *of_mdio_find_bus(struct device_node *mdio_bus_np)
503 d = class_find_device_by_of_node(&mdio_bus_class, mdio_bus_np);
504 return d ? to_mii_bus(d) : NULL;
506 EXPORT_SYMBOL(of_mdio_find_bus);
508 /* Walk the list of subnodes of a mdio bus and look for a node that
509 * matches the mdio device's address with its 'reg' property. If
510 * found, set the of_node pointer for the mdio device. This allows
511 * auto-probed phy devices to be supplied with information passed in
514 static void of_mdiobus_link_mdiodev(struct mii_bus *bus,
515 struct mdio_device *mdiodev)
517 struct device *dev = &mdiodev->dev;
518 struct device_node *child;
520 if (dev->of_node || !bus->dev.of_node)
523 for_each_available_child_of_node(bus->dev.of_node, child) {
526 addr = of_mdio_parse_addr(dev, child);
530 if (addr == mdiodev->addr) {
531 dev->of_node = child;
532 dev->fwnode = of_fwnode_handle(child);
537 #else /* !IS_ENABLED(CONFIG_OF_MDIO) */
538 static inline void of_mdiobus_link_mdiodev(struct mii_bus *mdio,
539 struct mdio_device *mdiodev)
545 * mdiobus_create_device_from_board_info - create a full MDIO device given
546 * a mdio_board_info structure
547 * @bus: MDIO bus to create the devices on
548 * @bi: mdio_board_info structure describing the devices
550 * Returns 0 on success or < 0 on error.
552 static int mdiobus_create_device(struct mii_bus *bus,
553 struct mdio_board_info *bi)
555 struct mdio_device *mdiodev;
558 mdiodev = mdio_device_create(bus, bi->mdio_addr);
562 strncpy(mdiodev->modalias, bi->modalias,
563 sizeof(mdiodev->modalias));
564 mdiodev->bus_match = mdio_device_bus_match;
565 mdiodev->dev.platform_data = (void *)bi->platform_data;
567 ret = mdio_device_register(mdiodev);
569 mdio_device_free(mdiodev);
575 * __mdiobus_register - bring up all the PHYs on a given bus and attach them to bus
576 * @bus: target mii_bus
577 * @owner: module containing bus accessor functions
579 * Description: Called by a bus driver to bring up all the PHYs
580 * on a given bus, and attach them to the bus. Drivers should use
581 * mdiobus_register() rather than __mdiobus_register() unless they
582 * need to pass a specific owner module. MDIO devices which are not
583 * PHYs will not be brought up by this function. They are expected to
584 * to be explicitly listed in DT and instantiated by of_mdiobus_register().
586 * Returns 0 on success or < 0 on error.
588 int __mdiobus_register(struct mii_bus *bus, struct module *owner)
590 struct mdio_device *mdiodev;
592 struct gpio_desc *gpiod;
594 if (NULL == bus || NULL == bus->name ||
595 NULL == bus->read || NULL == bus->write)
598 BUG_ON(bus->state != MDIOBUS_ALLOCATED &&
599 bus->state != MDIOBUS_UNREGISTERED);
602 bus->dev.parent = bus->parent;
603 bus->dev.class = &mdio_bus_class;
604 bus->dev.groups = NULL;
605 dev_set_name(&bus->dev, "%s", bus->id);
607 err = device_register(&bus->dev);
609 pr_err("mii_bus %s failed to register\n", bus->id);
613 mutex_init(&bus->mdio_lock);
615 /* de-assert bus level PHY GPIO reset */
616 gpiod = devm_gpiod_get_optional(&bus->dev, "reset", GPIOD_OUT_LOW);
618 dev_err(&bus->dev, "mii_bus %s couldn't get reset GPIO\n",
620 device_del(&bus->dev);
621 return PTR_ERR(gpiod);
623 bus->reset_gpiod = gpiod;
625 gpiod_set_value_cansleep(gpiod, 1);
626 udelay(bus->reset_delay_us);
627 gpiod_set_value_cansleep(gpiod, 0);
633 for (i = 0; i < PHY_MAX_ADDR; i++) {
634 if ((bus->phy_mask & (1 << i)) == 0) {
635 struct phy_device *phydev;
637 phydev = mdiobus_scan(bus, i);
638 if (IS_ERR(phydev) && (PTR_ERR(phydev) != -ENODEV)) {
639 err = PTR_ERR(phydev);
645 mdiobus_setup_mdiodev_from_board_info(bus, mdiobus_create_device);
647 bus->state = MDIOBUS_REGISTERED;
648 pr_info("%s: probed\n", bus->name);
653 mdiodev = bus->mdio_map[i];
657 mdiodev->device_remove(mdiodev);
658 mdiodev->device_free(mdiodev);
661 /* Put PHYs in RESET to save power */
662 if (bus->reset_gpiod)
663 gpiod_set_value_cansleep(bus->reset_gpiod, 1);
665 device_del(&bus->dev);
668 EXPORT_SYMBOL(__mdiobus_register);
670 void mdiobus_unregister(struct mii_bus *bus)
672 struct mdio_device *mdiodev;
675 BUG_ON(bus->state != MDIOBUS_REGISTERED);
676 bus->state = MDIOBUS_UNREGISTERED;
678 for (i = 0; i < PHY_MAX_ADDR; i++) {
679 mdiodev = bus->mdio_map[i];
683 if (mdiodev->reset_gpio)
684 gpiod_put(mdiodev->reset_gpio);
686 mdiodev->device_remove(mdiodev);
687 mdiodev->device_free(mdiodev);
690 /* Put PHYs in RESET to save power */
691 if (bus->reset_gpiod)
692 gpiod_set_value_cansleep(bus->reset_gpiod, 1);
694 device_del(&bus->dev);
696 EXPORT_SYMBOL(mdiobus_unregister);
699 * mdiobus_free - free a struct mii_bus
700 * @bus: mii_bus to free
702 * This function releases the reference to the underlying device
703 * object in the mii_bus. If this is the last reference, the mii_bus
706 void mdiobus_free(struct mii_bus *bus)
708 /* For compatibility with error handling in drivers. */
709 if (bus->state == MDIOBUS_ALLOCATED) {
714 BUG_ON(bus->state != MDIOBUS_UNREGISTERED);
715 bus->state = MDIOBUS_RELEASED;
717 put_device(&bus->dev);
719 EXPORT_SYMBOL(mdiobus_free);
722 * mdiobus_scan - scan a bus for MDIO devices.
723 * @bus: mii_bus to scan
724 * @addr: address on bus to scan
726 * This function scans the MDIO bus, looking for devices which can be
727 * identified using a vendor/product ID in registers 2 and 3. Not all
728 * MDIO devices have such registers, but PHY devices typically
729 * do. Hence this function assumes anything found is a PHY, or can be
730 * treated as a PHY. Other MDIO devices, such as switches, will
731 * probably not be found during the scan.
733 struct phy_device *mdiobus_scan(struct mii_bus *bus, int addr)
735 struct phy_device *phydev;
738 phydev = get_phy_device(bus, addr, false);
743 * For DT, see if the auto-probed phy has a correspoding child
744 * in the bus node, and set the of_node pointer in this case.
746 of_mdiobus_link_mdiodev(bus, &phydev->mdio);
748 err = phy_device_register(phydev);
750 phy_device_free(phydev);
751 return ERR_PTR(-ENODEV);
756 EXPORT_SYMBOL(mdiobus_scan);
758 static void mdiobus_stats_acct(struct mdio_bus_stats *stats, bool op, int ret)
760 u64_stats_update_begin(&stats->syncp);
762 u64_stats_inc(&stats->transfers);
764 u64_stats_inc(&stats->errors);
769 u64_stats_inc(&stats->reads);
771 u64_stats_inc(&stats->writes);
773 u64_stats_update_end(&stats->syncp);
777 * __mdiobus_read - Unlocked version of the mdiobus_read function
778 * @bus: the mii_bus struct
779 * @addr: the phy address
780 * @regnum: register number to read
782 * Read a MDIO bus register. Caller must hold the mdio bus lock.
784 * NOTE: MUST NOT be called from interrupt context.
786 int __mdiobus_read(struct mii_bus *bus, int addr, u32 regnum)
790 WARN_ON_ONCE(!mutex_is_locked(&bus->mdio_lock));
792 retval = bus->read(bus, addr, regnum);
794 trace_mdio_access(bus, 1, addr, regnum, retval, retval);
795 mdiobus_stats_acct(&bus->stats[addr], true, retval);
799 EXPORT_SYMBOL(__mdiobus_read);
802 * __mdiobus_write - Unlocked version of the mdiobus_write function
803 * @bus: the mii_bus struct
804 * @addr: the phy address
805 * @regnum: register number to write
806 * @val: value to write to @regnum
808 * Write a MDIO bus register. Caller must hold the mdio bus lock.
810 * NOTE: MUST NOT be called from interrupt context.
812 int __mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val)
816 WARN_ON_ONCE(!mutex_is_locked(&bus->mdio_lock));
818 err = bus->write(bus, addr, regnum, val);
820 trace_mdio_access(bus, 0, addr, regnum, val, err);
821 mdiobus_stats_acct(&bus->stats[addr], false, err);
825 EXPORT_SYMBOL(__mdiobus_write);
828 * __mdiobus_modify_changed - Unlocked version of the mdiobus_modify function
829 * @bus: the mii_bus struct
830 * @addr: the phy address
831 * @regnum: register number to modify
832 * @mask: bit mask of bits to clear
833 * @set: bit mask of bits to set
835 * Read, modify, and if any change, write the register value back to the
836 * device. Any error returns a negative number.
838 * NOTE: MUST NOT be called from interrupt context.
840 int __mdiobus_modify_changed(struct mii_bus *bus, int addr, u32 regnum,
845 ret = __mdiobus_read(bus, addr, regnum);
849 new = (ret & ~mask) | set;
853 ret = __mdiobus_write(bus, addr, regnum, new);
855 return ret < 0 ? ret : 1;
857 EXPORT_SYMBOL_GPL(__mdiobus_modify_changed);
860 * mdiobus_read_nested - Nested version of the mdiobus_read function
861 * @bus: the mii_bus struct
862 * @addr: the phy address
863 * @regnum: register number to read
865 * In case of nested MDIO bus access avoid lockdep false positives by
866 * using mutex_lock_nested().
868 * NOTE: MUST NOT be called from interrupt context,
869 * because the bus read/write functions may wait for an interrupt
870 * to conclude the operation.
872 int mdiobus_read_nested(struct mii_bus *bus, int addr, u32 regnum)
876 if (WARN_ON_ONCE(in_interrupt()))
879 mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED);
880 retval = __mdiobus_read(bus, addr, regnum);
881 mutex_unlock(&bus->mdio_lock);
885 EXPORT_SYMBOL(mdiobus_read_nested);
888 * mdiobus_read - Convenience function for reading a given MII mgmt register
889 * @bus: the mii_bus struct
890 * @addr: the phy address
891 * @regnum: register number to read
893 * NOTE: MUST NOT be called from interrupt context,
894 * because the bus read/write functions may wait for an interrupt
895 * to conclude the operation.
897 int mdiobus_read(struct mii_bus *bus, int addr, u32 regnum)
901 if (WARN_ON_ONCE(in_interrupt()))
904 mutex_lock(&bus->mdio_lock);
905 retval = __mdiobus_read(bus, addr, regnum);
906 mutex_unlock(&bus->mdio_lock);
910 EXPORT_SYMBOL(mdiobus_read);
913 * mdiobus_write_nested - Nested version of the mdiobus_write function
914 * @bus: the mii_bus struct
915 * @addr: the phy address
916 * @regnum: register number to write
917 * @val: value to write to @regnum
919 * In case of nested MDIO bus access avoid lockdep false positives by
920 * using mutex_lock_nested().
922 * NOTE: MUST NOT be called from interrupt context,
923 * because the bus read/write functions may wait for an interrupt
924 * to conclude the operation.
926 int mdiobus_write_nested(struct mii_bus *bus, int addr, u32 regnum, u16 val)
930 if (WARN_ON_ONCE(in_interrupt()))
933 mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED);
934 err = __mdiobus_write(bus, addr, regnum, val);
935 mutex_unlock(&bus->mdio_lock);
939 EXPORT_SYMBOL(mdiobus_write_nested);
942 * mdiobus_write - Convenience function for writing a given MII mgmt register
943 * @bus: the mii_bus struct
944 * @addr: the phy address
945 * @regnum: register number to write
946 * @val: value to write to @regnum
948 * NOTE: MUST NOT be called from interrupt context,
949 * because the bus read/write functions may wait for an interrupt
950 * to conclude the operation.
952 int mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val)
956 if (WARN_ON_ONCE(in_interrupt()))
959 mutex_lock(&bus->mdio_lock);
960 err = __mdiobus_write(bus, addr, regnum, val);
961 mutex_unlock(&bus->mdio_lock);
965 EXPORT_SYMBOL(mdiobus_write);
968 * mdiobus_modify - Convenience function for modifying a given mdio device
970 * @bus: the mii_bus struct
971 * @addr: the phy address
972 * @regnum: register number to write
973 * @mask: bit mask of bits to clear
974 * @set: bit mask of bits to set
976 int mdiobus_modify(struct mii_bus *bus, int addr, u32 regnum, u16 mask, u16 set)
980 if (WARN_ON_ONCE(in_interrupt()))
983 mutex_lock(&bus->mdio_lock);
984 err = __mdiobus_modify_changed(bus, addr, regnum, mask, set);
985 mutex_unlock(&bus->mdio_lock);
987 return err < 0 ? err : 0;
989 EXPORT_SYMBOL_GPL(mdiobus_modify);
992 * mdio_bus_match - determine if given MDIO driver supports the given
994 * @dev: target MDIO device
995 * @drv: given MDIO driver
997 * Description: Given a MDIO device, and a MDIO driver, return 1 if
998 * the driver supports the device. Otherwise, return 0. This may
999 * require calling the devices own match function, since different classes
1000 * of MDIO devices have different match criteria.
1002 static int mdio_bus_match(struct device *dev, struct device_driver *drv)
1004 struct mdio_device *mdio = to_mdio_device(dev);
1006 if (of_driver_match_device(dev, drv))
1009 if (mdio->bus_match)
1010 return mdio->bus_match(dev, drv);
1015 static int mdio_uevent(struct device *dev, struct kobj_uevent_env *env)
1019 /* Some devices have extra OF data and an OF-style MODALIAS */
1020 rc = of_device_uevent_modalias(dev, env);
1027 static struct attribute *mdio_bus_device_statistics_attrs[] = {
1028 &dev_attr_mdio_bus_device_transfers.attr.attr,
1029 &dev_attr_mdio_bus_device_errors.attr.attr,
1030 &dev_attr_mdio_bus_device_writes.attr.attr,
1031 &dev_attr_mdio_bus_device_reads.attr.attr,
1035 static const struct attribute_group mdio_bus_device_statistics_group = {
1036 .name = "statistics",
1037 .attrs = mdio_bus_device_statistics_attrs,
1040 static const struct attribute_group *mdio_bus_dev_groups[] = {
1041 &mdio_bus_device_statistics_group,
1045 struct bus_type mdio_bus_type = {
1047 .dev_groups = mdio_bus_dev_groups,
1048 .match = mdio_bus_match,
1049 .uevent = mdio_uevent,
1051 EXPORT_SYMBOL(mdio_bus_type);
1053 int __init mdio_bus_init(void)
1057 ret = class_register(&mdio_bus_class);
1059 ret = bus_register(&mdio_bus_type);
1061 class_unregister(&mdio_bus_class);
1066 EXPORT_SYMBOL_GPL(mdio_bus_init);
1068 #if IS_ENABLED(CONFIG_PHYLIB)
1069 void mdio_bus_exit(void)
1071 class_unregister(&mdio_bus_class);
1072 bus_unregister(&mdio_bus_type);
1074 EXPORT_SYMBOL_GPL(mdio_bus_exit);
1076 module_init(mdio_bus_init);
1077 /* no module_exit, intentional */
1078 MODULE_LICENSE("GPL");
1079 MODULE_DESCRIPTION("MDIO bus/device layer");