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