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 43 static 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 57 static 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 70 int 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 } 94 EXPORT_SYMBOL(mdiobus_register_device); 95 96 int 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 } 107 EXPORT_SYMBOL(mdiobus_unregister_device); 108 109 struct phy_device *mdiobus_get_phy(struct mii_bus *bus, int addr) 110 { 111 struct mdio_device *mdiodev = bus->mdio_map[addr]; 112 113 if (!mdiodev) 114 return NULL; 115 116 if (!(mdiodev->flags & MDIO_DEVICE_FLAG_PHY)) 117 return NULL; 118 119 return container_of(mdiodev, struct phy_device, mdio); 120 } 121 EXPORT_SYMBOL(mdiobus_get_phy); 122 123 bool mdiobus_is_registered_device(struct mii_bus *bus, int addr) 124 { 125 return bus->mdio_map[addr]; 126 } 127 EXPORT_SYMBOL(mdiobus_is_registered_device); 128 129 /** 130 * mdiobus_alloc_size - allocate a mii_bus structure 131 * @size: extra amount of memory to allocate for private storage. 132 * If non-zero, then bus->priv is points to that memory. 133 * 134 * Description: called by a bus driver to allocate an mii_bus 135 * structure to fill in. 136 */ 137 struct mii_bus *mdiobus_alloc_size(size_t size) 138 { 139 struct mii_bus *bus; 140 size_t aligned_size = ALIGN(sizeof(*bus), NETDEV_ALIGN); 141 size_t alloc_size; 142 int i; 143 144 /* If we alloc extra space, it should be aligned */ 145 if (size) 146 alloc_size = aligned_size + size; 147 else 148 alloc_size = sizeof(*bus); 149 150 bus = kzalloc(alloc_size, GFP_KERNEL); 151 if (!bus) 152 return NULL; 153 154 bus->state = MDIOBUS_ALLOCATED; 155 if (size) 156 bus->priv = (void *)bus + aligned_size; 157 158 /* Initialise the interrupts to polling and 64-bit seqcounts */ 159 for (i = 0; i < PHY_MAX_ADDR; i++) { 160 bus->irq[i] = PHY_POLL; 161 u64_stats_init(&bus->stats[i].syncp); 162 } 163 164 return bus; 165 } 166 EXPORT_SYMBOL(mdiobus_alloc_size); 167 168 /** 169 * mdiobus_release - mii_bus device release callback 170 * @d: the target struct device that contains the mii_bus 171 * 172 * Description: called when the last reference to an mii_bus is 173 * dropped, to free the underlying memory. 174 */ 175 static void mdiobus_release(struct device *d) 176 { 177 struct mii_bus *bus = to_mii_bus(d); 178 179 WARN(bus->state != MDIOBUS_RELEASED && 180 /* for compatibility with error handling in drivers */ 181 bus->state != MDIOBUS_ALLOCATED, 182 "%s: not in RELEASED or ALLOCATED state\n", 183 bus->id); 184 kfree(bus); 185 } 186 187 struct mdio_bus_stat_attr { 188 int addr; 189 unsigned int field_offset; 190 }; 191 192 static u64 mdio_bus_get_stat(struct mdio_bus_stats *s, unsigned int offset) 193 { 194 const char *p = (const char *)s + offset; 195 unsigned int start; 196 u64 val = 0; 197 198 do { 199 start = u64_stats_fetch_begin(&s->syncp); 200 val = u64_stats_read((const u64_stats_t *)p); 201 } while (u64_stats_fetch_retry(&s->syncp, start)); 202 203 return val; 204 } 205 206 static u64 mdio_bus_get_global_stat(struct mii_bus *bus, unsigned int offset) 207 { 208 unsigned int i; 209 u64 val = 0; 210 211 for (i = 0; i < PHY_MAX_ADDR; i++) 212 val += mdio_bus_get_stat(&bus->stats[i], offset); 213 214 return val; 215 } 216 217 static ssize_t mdio_bus_stat_field_show(struct device *dev, 218 struct device_attribute *attr, 219 char *buf) 220 { 221 struct mii_bus *bus = to_mii_bus(dev); 222 struct mdio_bus_stat_attr *sattr; 223 struct dev_ext_attribute *eattr; 224 u64 val; 225 226 eattr = container_of(attr, struct dev_ext_attribute, attr); 227 sattr = eattr->var; 228 229 if (sattr->addr < 0) 230 val = mdio_bus_get_global_stat(bus, sattr->field_offset); 231 else 232 val = mdio_bus_get_stat(&bus->stats[sattr->addr], 233 sattr->field_offset); 234 235 return sprintf(buf, "%llu\n", val); 236 } 237 238 static ssize_t mdio_bus_device_stat_field_show(struct device *dev, 239 struct device_attribute *attr, 240 char *buf) 241 { 242 struct mdio_device *mdiodev = to_mdio_device(dev); 243 struct mii_bus *bus = mdiodev->bus; 244 struct mdio_bus_stat_attr *sattr; 245 struct dev_ext_attribute *eattr; 246 int addr = mdiodev->addr; 247 u64 val; 248 249 eattr = container_of(attr, struct dev_ext_attribute, attr); 250 sattr = eattr->var; 251 252 val = mdio_bus_get_stat(&bus->stats[addr], sattr->field_offset); 253 254 return sprintf(buf, "%llu\n", val); 255 } 256 257 #define MDIO_BUS_STATS_ATTR_DECL(field, file) \ 258 static struct dev_ext_attribute dev_attr_mdio_bus_##field = { \ 259 .attr = { .attr = { .name = file, .mode = 0444 }, \ 260 .show = mdio_bus_stat_field_show, \ 261 }, \ 262 .var = &((struct mdio_bus_stat_attr) { \ 263 -1, offsetof(struct mdio_bus_stats, field) \ 264 }), \ 265 }; \ 266 static struct dev_ext_attribute dev_attr_mdio_bus_device_##field = { \ 267 .attr = { .attr = { .name = file, .mode = 0444 }, \ 268 .show = mdio_bus_device_stat_field_show, \ 269 }, \ 270 .var = &((struct mdio_bus_stat_attr) { \ 271 -1, offsetof(struct mdio_bus_stats, field) \ 272 }), \ 273 }; 274 275 #define MDIO_BUS_STATS_ATTR(field) \ 276 MDIO_BUS_STATS_ATTR_DECL(field, __stringify(field)) 277 278 MDIO_BUS_STATS_ATTR(transfers); 279 MDIO_BUS_STATS_ATTR(errors); 280 MDIO_BUS_STATS_ATTR(writes); 281 MDIO_BUS_STATS_ATTR(reads); 282 283 #define MDIO_BUS_STATS_ADDR_ATTR_DECL(field, addr, file) \ 284 static struct dev_ext_attribute dev_attr_mdio_bus_addr_##field##_##addr = { \ 285 .attr = { .attr = { .name = file, .mode = 0444 }, \ 286 .show = mdio_bus_stat_field_show, \ 287 }, \ 288 .var = &((struct mdio_bus_stat_attr) { \ 289 addr, offsetof(struct mdio_bus_stats, field) \ 290 }), \ 291 } 292 293 #define MDIO_BUS_STATS_ADDR_ATTR(field, addr) \ 294 MDIO_BUS_STATS_ADDR_ATTR_DECL(field, addr, \ 295 __stringify(field) "_" __stringify(addr)) 296 297 #define MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(addr) \ 298 MDIO_BUS_STATS_ADDR_ATTR(transfers, addr); \ 299 MDIO_BUS_STATS_ADDR_ATTR(errors, addr); \ 300 MDIO_BUS_STATS_ADDR_ATTR(writes, addr); \ 301 MDIO_BUS_STATS_ADDR_ATTR(reads, addr) \ 302 303 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(0); 304 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(1); 305 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(2); 306 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(3); 307 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(4); 308 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(5); 309 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(6); 310 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(7); 311 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(8); 312 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(9); 313 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(10); 314 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(11); 315 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(12); 316 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(13); 317 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(14); 318 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(15); 319 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(16); 320 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(17); 321 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(18); 322 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(19); 323 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(20); 324 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(21); 325 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(22); 326 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(23); 327 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(24); 328 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(25); 329 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(26); 330 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(27); 331 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(28); 332 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(29); 333 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(30); 334 MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(31); 335 336 #define MDIO_BUS_STATS_ADDR_ATTR_GROUP(addr) \ 337 &dev_attr_mdio_bus_addr_transfers_##addr.attr.attr, \ 338 &dev_attr_mdio_bus_addr_errors_##addr.attr.attr, \ 339 &dev_attr_mdio_bus_addr_writes_##addr.attr.attr, \ 340 &dev_attr_mdio_bus_addr_reads_##addr.attr.attr \ 341 342 static struct attribute *mdio_bus_statistics_attrs[] = { 343 &dev_attr_mdio_bus_transfers.attr.attr, 344 &dev_attr_mdio_bus_errors.attr.attr, 345 &dev_attr_mdio_bus_writes.attr.attr, 346 &dev_attr_mdio_bus_reads.attr.attr, 347 MDIO_BUS_STATS_ADDR_ATTR_GROUP(0), 348 MDIO_BUS_STATS_ADDR_ATTR_GROUP(1), 349 MDIO_BUS_STATS_ADDR_ATTR_GROUP(2), 350 MDIO_BUS_STATS_ADDR_ATTR_GROUP(3), 351 MDIO_BUS_STATS_ADDR_ATTR_GROUP(4), 352 MDIO_BUS_STATS_ADDR_ATTR_GROUP(5), 353 MDIO_BUS_STATS_ADDR_ATTR_GROUP(6), 354 MDIO_BUS_STATS_ADDR_ATTR_GROUP(7), 355 MDIO_BUS_STATS_ADDR_ATTR_GROUP(8), 356 MDIO_BUS_STATS_ADDR_ATTR_GROUP(9), 357 MDIO_BUS_STATS_ADDR_ATTR_GROUP(10), 358 MDIO_BUS_STATS_ADDR_ATTR_GROUP(11), 359 MDIO_BUS_STATS_ADDR_ATTR_GROUP(12), 360 MDIO_BUS_STATS_ADDR_ATTR_GROUP(13), 361 MDIO_BUS_STATS_ADDR_ATTR_GROUP(14), 362 MDIO_BUS_STATS_ADDR_ATTR_GROUP(15), 363 MDIO_BUS_STATS_ADDR_ATTR_GROUP(16), 364 MDIO_BUS_STATS_ADDR_ATTR_GROUP(17), 365 MDIO_BUS_STATS_ADDR_ATTR_GROUP(18), 366 MDIO_BUS_STATS_ADDR_ATTR_GROUP(19), 367 MDIO_BUS_STATS_ADDR_ATTR_GROUP(20), 368 MDIO_BUS_STATS_ADDR_ATTR_GROUP(21), 369 MDIO_BUS_STATS_ADDR_ATTR_GROUP(22), 370 MDIO_BUS_STATS_ADDR_ATTR_GROUP(23), 371 MDIO_BUS_STATS_ADDR_ATTR_GROUP(24), 372 MDIO_BUS_STATS_ADDR_ATTR_GROUP(25), 373 MDIO_BUS_STATS_ADDR_ATTR_GROUP(26), 374 MDIO_BUS_STATS_ADDR_ATTR_GROUP(27), 375 MDIO_BUS_STATS_ADDR_ATTR_GROUP(28), 376 MDIO_BUS_STATS_ADDR_ATTR_GROUP(29), 377 MDIO_BUS_STATS_ADDR_ATTR_GROUP(30), 378 MDIO_BUS_STATS_ADDR_ATTR_GROUP(31), 379 NULL, 380 }; 381 382 static const struct attribute_group mdio_bus_statistics_group = { 383 .name = "statistics", 384 .attrs = mdio_bus_statistics_attrs, 385 }; 386 387 static const struct attribute_group *mdio_bus_groups[] = { 388 &mdio_bus_statistics_group, 389 NULL, 390 }; 391 392 static struct class mdio_bus_class = { 393 .name = "mdio_bus", 394 .dev_release = mdiobus_release, 395 .dev_groups = mdio_bus_groups, 396 }; 397 398 /** 399 * mdio_find_bus - Given the name of a mdiobus, find the mii_bus. 400 * @mdio_name: The name of a mdiobus. 401 * 402 * Returns a reference to the mii_bus, or NULL if none found. The 403 * embedded struct device will have its reference count incremented, 404 * and this must be put_deviced'ed once the bus is finished with. 405 */ 406 struct mii_bus *mdio_find_bus(const char *mdio_name) 407 { 408 struct device *d; 409 410 d = class_find_device_by_name(&mdio_bus_class, mdio_name); 411 return d ? to_mii_bus(d) : NULL; 412 } 413 EXPORT_SYMBOL(mdio_find_bus); 414 415 #if IS_ENABLED(CONFIG_OF_MDIO) 416 /** 417 * of_mdio_find_bus - Given an mii_bus node, find the mii_bus. 418 * @mdio_bus_np: Pointer to the mii_bus. 419 * 420 * Returns a reference to the mii_bus, or NULL if none found. The 421 * embedded struct device will have its reference count incremented, 422 * and this must be put once the bus is finished with. 423 * 424 * Because the association of a device_node and mii_bus is made via 425 * of_mdiobus_register(), the mii_bus cannot be found before it is 426 * registered with of_mdiobus_register(). 427 * 428 */ 429 struct mii_bus *of_mdio_find_bus(struct device_node *mdio_bus_np) 430 { 431 struct device *d; 432 433 if (!mdio_bus_np) 434 return NULL; 435 436 d = class_find_device_by_of_node(&mdio_bus_class, mdio_bus_np); 437 return d ? to_mii_bus(d) : NULL; 438 } 439 EXPORT_SYMBOL(of_mdio_find_bus); 440 441 /* Walk the list of subnodes of a mdio bus and look for a node that 442 * matches the mdio device's address with its 'reg' property. If 443 * found, set the of_node pointer for the mdio device. This allows 444 * auto-probed phy devices to be supplied with information passed in 445 * via DT. 446 */ 447 static void of_mdiobus_link_mdiodev(struct mii_bus *bus, 448 struct mdio_device *mdiodev) 449 { 450 struct device *dev = &mdiodev->dev; 451 struct device_node *child; 452 453 if (dev->of_node || !bus->dev.of_node) 454 return; 455 456 for_each_available_child_of_node(bus->dev.of_node, child) { 457 int addr; 458 459 addr = of_mdio_parse_addr(dev, child); 460 if (addr < 0) 461 continue; 462 463 if (addr == mdiodev->addr) { 464 device_set_node(dev, of_fwnode_handle(child)); 465 return; 466 } 467 } 468 } 469 #else /* !IS_ENABLED(CONFIG_OF_MDIO) */ 470 static inline void of_mdiobus_link_mdiodev(struct mii_bus *mdio, 471 struct mdio_device *mdiodev) 472 { 473 } 474 #endif 475 476 /** 477 * mdiobus_create_device - create a full MDIO device given 478 * a mdio_board_info structure 479 * @bus: MDIO bus to create the devices on 480 * @bi: mdio_board_info structure describing the devices 481 * 482 * Returns 0 on success or < 0 on error. 483 */ 484 static int mdiobus_create_device(struct mii_bus *bus, 485 struct mdio_board_info *bi) 486 { 487 struct mdio_device *mdiodev; 488 int ret = 0; 489 490 mdiodev = mdio_device_create(bus, bi->mdio_addr); 491 if (IS_ERR(mdiodev)) 492 return -ENODEV; 493 494 strncpy(mdiodev->modalias, bi->modalias, 495 sizeof(mdiodev->modalias)); 496 mdiodev->bus_match = mdio_device_bus_match; 497 mdiodev->dev.platform_data = (void *)bi->platform_data; 498 499 ret = mdio_device_register(mdiodev); 500 if (ret) 501 mdio_device_free(mdiodev); 502 503 return ret; 504 } 505 506 /** 507 * __mdiobus_register - bring up all the PHYs on a given bus and attach them to bus 508 * @bus: target mii_bus 509 * @owner: module containing bus accessor functions 510 * 511 * Description: Called by a bus driver to bring up all the PHYs 512 * on a given bus, and attach them to the bus. Drivers should use 513 * mdiobus_register() rather than __mdiobus_register() unless they 514 * need to pass a specific owner module. MDIO devices which are not 515 * PHYs will not be brought up by this function. They are expected 516 * to be explicitly listed in DT and instantiated by of_mdiobus_register(). 517 * 518 * Returns 0 on success or < 0 on error. 519 */ 520 int __mdiobus_register(struct mii_bus *bus, struct module *owner) 521 { 522 struct mdio_device *mdiodev; 523 int i, err; 524 struct gpio_desc *gpiod; 525 526 if (NULL == bus || NULL == bus->name || 527 NULL == bus->read || NULL == bus->write) 528 return -EINVAL; 529 530 if (bus->parent && bus->parent->of_node) 531 bus->parent->of_node->fwnode.flags |= 532 FWNODE_FLAG_NEEDS_CHILD_BOUND_ON_ADD; 533 534 WARN(bus->state != MDIOBUS_ALLOCATED && 535 bus->state != MDIOBUS_UNREGISTERED, 536 "%s: not in ALLOCATED or UNREGISTERED state\n", bus->id); 537 538 bus->owner = owner; 539 bus->dev.parent = bus->parent; 540 bus->dev.class = &mdio_bus_class; 541 bus->dev.groups = NULL; 542 dev_set_name(&bus->dev, "%s", bus->id); 543 544 /* We need to set state to MDIOBUS_UNREGISTERED to correctly release 545 * the device in mdiobus_free() 546 * 547 * State will be updated later in this function in case of success 548 */ 549 bus->state = MDIOBUS_UNREGISTERED; 550 551 err = device_register(&bus->dev); 552 if (err) { 553 pr_err("mii_bus %s failed to register\n", bus->id); 554 return -EINVAL; 555 } 556 557 mutex_init(&bus->mdio_lock); 558 mutex_init(&bus->shared_lock); 559 560 /* assert bus level PHY GPIO reset */ 561 gpiod = devm_gpiod_get_optional(&bus->dev, "reset", GPIOD_OUT_HIGH); 562 if (IS_ERR(gpiod)) { 563 err = dev_err_probe(&bus->dev, PTR_ERR(gpiod), 564 "mii_bus %s couldn't get reset GPIO\n", 565 bus->id); 566 device_del(&bus->dev); 567 return err; 568 } else if (gpiod) { 569 bus->reset_gpiod = gpiod; 570 fsleep(bus->reset_delay_us); 571 gpiod_set_value_cansleep(gpiod, 0); 572 if (bus->reset_post_delay_us > 0) 573 fsleep(bus->reset_post_delay_us); 574 } 575 576 if (bus->reset) { 577 err = bus->reset(bus); 578 if (err) 579 goto error_reset_gpiod; 580 } 581 582 for (i = 0; i < PHY_MAX_ADDR; i++) { 583 if ((bus->phy_mask & (1 << i)) == 0) { 584 struct phy_device *phydev; 585 586 phydev = mdiobus_scan(bus, i); 587 if (IS_ERR(phydev) && (PTR_ERR(phydev) != -ENODEV)) { 588 err = PTR_ERR(phydev); 589 goto error; 590 } 591 } 592 } 593 594 mdiobus_setup_mdiodev_from_board_info(bus, mdiobus_create_device); 595 596 bus->state = MDIOBUS_REGISTERED; 597 pr_info("%s: probed\n", bus->name); 598 return 0; 599 600 error: 601 while (--i >= 0) { 602 mdiodev = bus->mdio_map[i]; 603 if (!mdiodev) 604 continue; 605 606 mdiodev->device_remove(mdiodev); 607 mdiodev->device_free(mdiodev); 608 } 609 error_reset_gpiod: 610 /* Put PHYs in RESET to save power */ 611 if (bus->reset_gpiod) 612 gpiod_set_value_cansleep(bus->reset_gpiod, 1); 613 614 device_del(&bus->dev); 615 return err; 616 } 617 EXPORT_SYMBOL(__mdiobus_register); 618 619 void mdiobus_unregister(struct mii_bus *bus) 620 { 621 struct mdio_device *mdiodev; 622 int i; 623 624 if (WARN_ON_ONCE(bus->state != MDIOBUS_REGISTERED)) 625 return; 626 bus->state = MDIOBUS_UNREGISTERED; 627 628 for (i = 0; i < PHY_MAX_ADDR; i++) { 629 mdiodev = bus->mdio_map[i]; 630 if (!mdiodev) 631 continue; 632 633 if (mdiodev->reset_gpio) 634 gpiod_put(mdiodev->reset_gpio); 635 636 mdiodev->device_remove(mdiodev); 637 mdiodev->device_free(mdiodev); 638 } 639 640 /* Put PHYs in RESET to save power */ 641 if (bus->reset_gpiod) 642 gpiod_set_value_cansleep(bus->reset_gpiod, 1); 643 644 device_del(&bus->dev); 645 } 646 EXPORT_SYMBOL(mdiobus_unregister); 647 648 /** 649 * mdiobus_free - free a struct mii_bus 650 * @bus: mii_bus to free 651 * 652 * This function releases the reference to the underlying device 653 * object in the mii_bus. If this is the last reference, the mii_bus 654 * will be freed. 655 */ 656 void mdiobus_free(struct mii_bus *bus) 657 { 658 /* For compatibility with error handling in drivers. */ 659 if (bus->state == MDIOBUS_ALLOCATED) { 660 kfree(bus); 661 return; 662 } 663 664 WARN(bus->state != MDIOBUS_UNREGISTERED, 665 "%s: not in UNREGISTERED state\n", bus->id); 666 bus->state = MDIOBUS_RELEASED; 667 668 put_device(&bus->dev); 669 } 670 EXPORT_SYMBOL(mdiobus_free); 671 672 /** 673 * mdiobus_scan - scan a bus for MDIO devices. 674 * @bus: mii_bus to scan 675 * @addr: address on bus to scan 676 * 677 * This function scans the MDIO bus, looking for devices which can be 678 * identified using a vendor/product ID in registers 2 and 3. Not all 679 * MDIO devices have such registers, but PHY devices typically 680 * do. Hence this function assumes anything found is a PHY, or can be 681 * treated as a PHY. Other MDIO devices, such as switches, will 682 * probably not be found during the scan. 683 */ 684 struct phy_device *mdiobus_scan(struct mii_bus *bus, int addr) 685 { 686 struct phy_device *phydev = ERR_PTR(-ENODEV); 687 int err; 688 689 switch (bus->probe_capabilities) { 690 case MDIOBUS_NO_CAP: 691 case MDIOBUS_C22: 692 phydev = get_phy_device(bus, addr, false); 693 break; 694 case MDIOBUS_C45: 695 phydev = get_phy_device(bus, addr, true); 696 break; 697 case MDIOBUS_C22_C45: 698 phydev = get_phy_device(bus, addr, false); 699 if (IS_ERR(phydev)) 700 phydev = get_phy_device(bus, addr, true); 701 break; 702 } 703 704 if (IS_ERR(phydev)) 705 return phydev; 706 707 /* 708 * For DT, see if the auto-probed phy has a correspoding child 709 * in the bus node, and set the of_node pointer in this case. 710 */ 711 of_mdiobus_link_mdiodev(bus, &phydev->mdio); 712 713 err = phy_device_register(phydev); 714 if (err) { 715 phy_device_free(phydev); 716 return ERR_PTR(-ENODEV); 717 } 718 719 return phydev; 720 } 721 EXPORT_SYMBOL(mdiobus_scan); 722 723 static void mdiobus_stats_acct(struct mdio_bus_stats *stats, bool op, int ret) 724 { 725 preempt_disable(); 726 u64_stats_update_begin(&stats->syncp); 727 728 u64_stats_inc(&stats->transfers); 729 if (ret < 0) { 730 u64_stats_inc(&stats->errors); 731 goto out; 732 } 733 734 if (op) 735 u64_stats_inc(&stats->reads); 736 else 737 u64_stats_inc(&stats->writes); 738 out: 739 u64_stats_update_end(&stats->syncp); 740 preempt_enable(); 741 } 742 743 /** 744 * __mdiobus_read - Unlocked version of the mdiobus_read function 745 * @bus: the mii_bus struct 746 * @addr: the phy address 747 * @regnum: register number to read 748 * 749 * Read a MDIO bus register. Caller must hold the mdio bus lock. 750 * 751 * NOTE: MUST NOT be called from interrupt context. 752 */ 753 int __mdiobus_read(struct mii_bus *bus, int addr, u32 regnum) 754 { 755 int retval; 756 757 lockdep_assert_held_once(&bus->mdio_lock); 758 759 retval = bus->read(bus, addr, regnum); 760 761 trace_mdio_access(bus, 1, addr, regnum, retval, retval); 762 mdiobus_stats_acct(&bus->stats[addr], true, retval); 763 764 return retval; 765 } 766 EXPORT_SYMBOL(__mdiobus_read); 767 768 /** 769 * __mdiobus_write - Unlocked version of the mdiobus_write function 770 * @bus: the mii_bus struct 771 * @addr: the phy address 772 * @regnum: register number to write 773 * @val: value to write to @regnum 774 * 775 * Write a MDIO bus register. Caller must hold the mdio bus lock. 776 * 777 * NOTE: MUST NOT be called from interrupt context. 778 */ 779 int __mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val) 780 { 781 int err; 782 783 lockdep_assert_held_once(&bus->mdio_lock); 784 785 err = bus->write(bus, addr, regnum, val); 786 787 trace_mdio_access(bus, 0, addr, regnum, val, err); 788 mdiobus_stats_acct(&bus->stats[addr], false, err); 789 790 return err; 791 } 792 EXPORT_SYMBOL(__mdiobus_write); 793 794 /** 795 * __mdiobus_modify_changed - Unlocked version of the mdiobus_modify function 796 * @bus: the mii_bus struct 797 * @addr: the phy address 798 * @regnum: register number to modify 799 * @mask: bit mask of bits to clear 800 * @set: bit mask of bits to set 801 * 802 * Read, modify, and if any change, write the register value back to the 803 * device. Any error returns a negative number. 804 * 805 * NOTE: MUST NOT be called from interrupt context. 806 */ 807 int __mdiobus_modify_changed(struct mii_bus *bus, int addr, u32 regnum, 808 u16 mask, u16 set) 809 { 810 int new, ret; 811 812 ret = __mdiobus_read(bus, addr, regnum); 813 if (ret < 0) 814 return ret; 815 816 new = (ret & ~mask) | set; 817 if (new == ret) 818 return 0; 819 820 ret = __mdiobus_write(bus, addr, regnum, new); 821 822 return ret < 0 ? ret : 1; 823 } 824 EXPORT_SYMBOL_GPL(__mdiobus_modify_changed); 825 826 /** 827 * mdiobus_read_nested - Nested version of the mdiobus_read function 828 * @bus: the mii_bus struct 829 * @addr: the phy address 830 * @regnum: register number to read 831 * 832 * In case of nested MDIO bus access avoid lockdep false positives by 833 * using mutex_lock_nested(). 834 * 835 * NOTE: MUST NOT be called from interrupt context, 836 * because the bus read/write functions may wait for an interrupt 837 * to conclude the operation. 838 */ 839 int mdiobus_read_nested(struct mii_bus *bus, int addr, u32 regnum) 840 { 841 int retval; 842 843 mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED); 844 retval = __mdiobus_read(bus, addr, regnum); 845 mutex_unlock(&bus->mdio_lock); 846 847 return retval; 848 } 849 EXPORT_SYMBOL(mdiobus_read_nested); 850 851 /** 852 * mdiobus_read - Convenience function for reading a given MII mgmt register 853 * @bus: the mii_bus struct 854 * @addr: the phy address 855 * @regnum: register number to read 856 * 857 * NOTE: MUST NOT be called from interrupt context, 858 * because the bus read/write functions may wait for an interrupt 859 * to conclude the operation. 860 */ 861 int mdiobus_read(struct mii_bus *bus, int addr, u32 regnum) 862 { 863 int retval; 864 865 mutex_lock(&bus->mdio_lock); 866 retval = __mdiobus_read(bus, addr, regnum); 867 mutex_unlock(&bus->mdio_lock); 868 869 return retval; 870 } 871 EXPORT_SYMBOL(mdiobus_read); 872 873 /** 874 * mdiobus_write_nested - Nested version of the mdiobus_write function 875 * @bus: the mii_bus struct 876 * @addr: the phy address 877 * @regnum: register number to write 878 * @val: value to write to @regnum 879 * 880 * In case of nested MDIO bus access avoid lockdep false positives by 881 * using mutex_lock_nested(). 882 * 883 * NOTE: MUST NOT be called from interrupt context, 884 * because the bus read/write functions may wait for an interrupt 885 * to conclude the operation. 886 */ 887 int mdiobus_write_nested(struct mii_bus *bus, int addr, u32 regnum, u16 val) 888 { 889 int err; 890 891 mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED); 892 err = __mdiobus_write(bus, addr, regnum, val); 893 mutex_unlock(&bus->mdio_lock); 894 895 return err; 896 } 897 EXPORT_SYMBOL(mdiobus_write_nested); 898 899 /** 900 * mdiobus_write - Convenience function for writing a given MII mgmt register 901 * @bus: the mii_bus struct 902 * @addr: the phy address 903 * @regnum: register number to write 904 * @val: value to write to @regnum 905 * 906 * NOTE: MUST NOT be called from interrupt context, 907 * because the bus read/write functions may wait for an interrupt 908 * to conclude the operation. 909 */ 910 int mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val) 911 { 912 int err; 913 914 mutex_lock(&bus->mdio_lock); 915 err = __mdiobus_write(bus, addr, regnum, val); 916 mutex_unlock(&bus->mdio_lock); 917 918 return err; 919 } 920 EXPORT_SYMBOL(mdiobus_write); 921 922 /** 923 * mdiobus_modify - Convenience function for modifying a given mdio device 924 * register 925 * @bus: the mii_bus struct 926 * @addr: the phy address 927 * @regnum: register number to write 928 * @mask: bit mask of bits to clear 929 * @set: bit mask of bits to set 930 */ 931 int mdiobus_modify(struct mii_bus *bus, int addr, u32 regnum, u16 mask, u16 set) 932 { 933 int err; 934 935 mutex_lock(&bus->mdio_lock); 936 err = __mdiobus_modify_changed(bus, addr, regnum, mask, set); 937 mutex_unlock(&bus->mdio_lock); 938 939 return err < 0 ? err : 0; 940 } 941 EXPORT_SYMBOL_GPL(mdiobus_modify); 942 943 /** 944 * mdiobus_modify_changed - Convenience function for modifying a given mdio 945 * device register and returning if it changed 946 * @bus: the mii_bus struct 947 * @addr: the phy address 948 * @regnum: register number to write 949 * @mask: bit mask of bits to clear 950 * @set: bit mask of bits to set 951 */ 952 int mdiobus_modify_changed(struct mii_bus *bus, int addr, u32 regnum, 953 u16 mask, u16 set) 954 { 955 int err; 956 957 mutex_lock(&bus->mdio_lock); 958 err = __mdiobus_modify_changed(bus, addr, regnum, mask, set); 959 mutex_unlock(&bus->mdio_lock); 960 961 return err; 962 } 963 EXPORT_SYMBOL_GPL(mdiobus_modify_changed); 964 965 /** 966 * mdio_bus_match - determine if given MDIO driver supports the given 967 * MDIO device 968 * @dev: target MDIO device 969 * @drv: given MDIO driver 970 * 971 * Description: Given a MDIO device, and a MDIO driver, return 1 if 972 * the driver supports the device. Otherwise, return 0. This may 973 * require calling the devices own match function, since different classes 974 * of MDIO devices have different match criteria. 975 */ 976 static int mdio_bus_match(struct device *dev, struct device_driver *drv) 977 { 978 struct mdio_driver *mdiodrv = to_mdio_driver(drv); 979 struct mdio_device *mdio = to_mdio_device(dev); 980 981 /* Both the driver and device must type-match */ 982 if (!(mdiodrv->mdiodrv.flags & MDIO_DEVICE_IS_PHY) != 983 !(mdio->flags & MDIO_DEVICE_FLAG_PHY)) 984 return 0; 985 986 if (of_driver_match_device(dev, drv)) 987 return 1; 988 989 if (mdio->bus_match) 990 return mdio->bus_match(dev, drv); 991 992 return 0; 993 } 994 995 static int mdio_uevent(struct device *dev, struct kobj_uevent_env *env) 996 { 997 int rc; 998 999 /* Some devices have extra OF data and an OF-style MODALIAS */ 1000 rc = of_device_uevent_modalias(dev, env); 1001 if (rc != -ENODEV) 1002 return rc; 1003 1004 return 0; 1005 } 1006 1007 static struct attribute *mdio_bus_device_statistics_attrs[] = { 1008 &dev_attr_mdio_bus_device_transfers.attr.attr, 1009 &dev_attr_mdio_bus_device_errors.attr.attr, 1010 &dev_attr_mdio_bus_device_writes.attr.attr, 1011 &dev_attr_mdio_bus_device_reads.attr.attr, 1012 NULL, 1013 }; 1014 1015 static const struct attribute_group mdio_bus_device_statistics_group = { 1016 .name = "statistics", 1017 .attrs = mdio_bus_device_statistics_attrs, 1018 }; 1019 1020 static const struct attribute_group *mdio_bus_dev_groups[] = { 1021 &mdio_bus_device_statistics_group, 1022 NULL, 1023 }; 1024 1025 struct bus_type mdio_bus_type = { 1026 .name = "mdio_bus", 1027 .dev_groups = mdio_bus_dev_groups, 1028 .match = mdio_bus_match, 1029 .uevent = mdio_uevent, 1030 }; 1031 EXPORT_SYMBOL(mdio_bus_type); 1032 1033 int __init mdio_bus_init(void) 1034 { 1035 int ret; 1036 1037 ret = class_register(&mdio_bus_class); 1038 if (!ret) { 1039 ret = bus_register(&mdio_bus_type); 1040 if (ret) 1041 class_unregister(&mdio_bus_class); 1042 } 1043 1044 return ret; 1045 } 1046 EXPORT_SYMBOL_GPL(mdio_bus_init); 1047 1048 #if IS_ENABLED(CONFIG_PHYLIB) 1049 void mdio_bus_exit(void) 1050 { 1051 class_unregister(&mdio_bus_class); 1052 bus_unregister(&mdio_bus_type); 1053 } 1054 EXPORT_SYMBOL_GPL(mdio_bus_exit); 1055 #else 1056 module_init(mdio_bus_init); 1057 /* no module_exit, intentional */ 1058 MODULE_LICENSE("GPL"); 1059 MODULE_DESCRIPTION("MDIO bus/device layer"); 1060 #endif 1061