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