1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Copyright (C) 2006 Benjamin Herrenschmidt, IBM Corp. 4 * <benh@kernel.crashing.org> 5 * and Arnd Bergmann, IBM Corp. 6 * Merged from powerpc/kernel/of_platform.c and 7 * sparc{,64}/kernel/of_device.c by Stephen Rothwell 8 */ 9 10 #define pr_fmt(fmt) "OF: " fmt 11 12 #include <linux/errno.h> 13 #include <linux/module.h> 14 #include <linux/amba/bus.h> 15 #include <linux/device.h> 16 #include <linux/dma-mapping.h> 17 #include <linux/slab.h> 18 #include <linux/of_address.h> 19 #include <linux/of_device.h> 20 #include <linux/of_iommu.h> 21 #include <linux/of_irq.h> 22 #include <linux/of_platform.h> 23 #include <linux/platform_device.h> 24 25 const struct of_device_id of_default_bus_match_table[] = { 26 { .compatible = "simple-bus", }, 27 { .compatible = "simple-mfd", }, 28 { .compatible = "isa", }, 29 #ifdef CONFIG_ARM_AMBA 30 { .compatible = "arm,amba-bus", }, 31 #endif /* CONFIG_ARM_AMBA */ 32 {} /* Empty terminated list */ 33 }; 34 35 static const struct of_device_id of_skipped_node_table[] = { 36 { .compatible = "operating-points-v2", }, 37 {} /* Empty terminated list */ 38 }; 39 40 static int of_dev_node_match(struct device *dev, void *data) 41 { 42 return dev->of_node == data; 43 } 44 45 /** 46 * of_find_device_by_node - Find the platform_device associated with a node 47 * @np: Pointer to device tree node 48 * 49 * Takes a reference to the embedded struct device which needs to be dropped 50 * after use. 51 * 52 * Returns platform_device pointer, or NULL if not found 53 */ 54 struct platform_device *of_find_device_by_node(struct device_node *np) 55 { 56 struct device *dev; 57 58 dev = bus_find_device(&platform_bus_type, NULL, np, of_dev_node_match); 59 return dev ? to_platform_device(dev) : NULL; 60 } 61 EXPORT_SYMBOL(of_find_device_by_node); 62 63 #ifdef CONFIG_OF_ADDRESS 64 /* 65 * The following routines scan a subtree and registers a device for 66 * each applicable node. 67 * 68 * Note: sparc doesn't use these routines because it has a different 69 * mechanism for creating devices from device tree nodes. 70 */ 71 72 /** 73 * of_device_make_bus_id - Use the device node data to assign a unique name 74 * @dev: pointer to device structure that is linked to a device tree node 75 * 76 * This routine will first try using the translated bus address to 77 * derive a unique name. If it cannot, then it will prepend names from 78 * parent nodes until a unique name can be derived. 79 */ 80 static void of_device_make_bus_id(struct device *dev) 81 { 82 struct device_node *node = dev->of_node; 83 const __be32 *reg; 84 u64 addr; 85 86 /* Construct the name, using parent nodes if necessary to ensure uniqueness */ 87 while (node->parent) { 88 /* 89 * If the address can be translated, then that is as much 90 * uniqueness as we need. Make it the first component and return 91 */ 92 reg = of_get_property(node, "reg", NULL); 93 if (reg && (addr = of_translate_address(node, reg)) != OF_BAD_ADDR) { 94 dev_set_name(dev, dev_name(dev) ? "%llx.%pOFn:%s" : "%llx.%pOFn", 95 (unsigned long long)addr, node, 96 dev_name(dev)); 97 return; 98 } 99 100 /* format arguments only used if dev_name() resolves to NULL */ 101 dev_set_name(dev, dev_name(dev) ? "%s:%s" : "%s", 102 kbasename(node->full_name), dev_name(dev)); 103 node = node->parent; 104 } 105 } 106 107 /** 108 * of_device_alloc - Allocate and initialize an of_device 109 * @np: device node to assign to device 110 * @bus_id: Name to assign to the device. May be null to use default name. 111 * @parent: Parent device. 112 */ 113 struct platform_device *of_device_alloc(struct device_node *np, 114 const char *bus_id, 115 struct device *parent) 116 { 117 struct platform_device *dev; 118 int rc, i, num_reg = 0, num_irq; 119 struct resource *res, temp_res; 120 121 dev = platform_device_alloc("", PLATFORM_DEVID_NONE); 122 if (!dev) 123 return NULL; 124 125 /* count the io and irq resources */ 126 while (of_address_to_resource(np, num_reg, &temp_res) == 0) 127 num_reg++; 128 num_irq = of_irq_count(np); 129 130 /* Populate the resource table */ 131 if (num_irq || num_reg) { 132 res = kcalloc(num_irq + num_reg, sizeof(*res), GFP_KERNEL); 133 if (!res) { 134 platform_device_put(dev); 135 return NULL; 136 } 137 138 dev->num_resources = num_reg + num_irq; 139 dev->resource = res; 140 for (i = 0; i < num_reg; i++, res++) { 141 rc = of_address_to_resource(np, i, res); 142 WARN_ON(rc); 143 } 144 if (of_irq_to_resource_table(np, res, num_irq) != num_irq) 145 pr_debug("not all legacy IRQ resources mapped for %pOFn\n", 146 np); 147 } 148 149 dev->dev.of_node = of_node_get(np); 150 dev->dev.fwnode = &np->fwnode; 151 dev->dev.parent = parent ? : &platform_bus; 152 153 if (bus_id) 154 dev_set_name(&dev->dev, "%s", bus_id); 155 else 156 of_device_make_bus_id(&dev->dev); 157 158 return dev; 159 } 160 EXPORT_SYMBOL(of_device_alloc); 161 162 /** 163 * of_platform_device_create_pdata - Alloc, initialize and register an of_device 164 * @np: pointer to node to create device for 165 * @bus_id: name to assign device 166 * @platform_data: pointer to populate platform_data pointer with 167 * @parent: Linux device model parent device. 168 * 169 * Returns pointer to created platform device, or NULL if a device was not 170 * registered. Unavailable devices will not get registered. 171 */ 172 static struct platform_device *of_platform_device_create_pdata( 173 struct device_node *np, 174 const char *bus_id, 175 void *platform_data, 176 struct device *parent) 177 { 178 struct platform_device *dev; 179 180 if (!of_device_is_available(np) || 181 of_node_test_and_set_flag(np, OF_POPULATED)) 182 return NULL; 183 184 dev = of_device_alloc(np, bus_id, parent); 185 if (!dev) 186 goto err_clear_flag; 187 188 dev->dev.coherent_dma_mask = DMA_BIT_MASK(32); 189 if (!dev->dev.dma_mask) 190 dev->dev.dma_mask = &dev->dev.coherent_dma_mask; 191 dev->dev.bus = &platform_bus_type; 192 dev->dev.platform_data = platform_data; 193 of_msi_configure(&dev->dev, dev->dev.of_node); 194 195 if (of_device_add(dev) != 0) { 196 platform_device_put(dev); 197 goto err_clear_flag; 198 } 199 200 return dev; 201 202 err_clear_flag: 203 of_node_clear_flag(np, OF_POPULATED); 204 return NULL; 205 } 206 207 /** 208 * of_platform_device_create - Alloc, initialize and register an of_device 209 * @np: pointer to node to create device for 210 * @bus_id: name to assign device 211 * @parent: Linux device model parent device. 212 * 213 * Returns pointer to created platform device, or NULL if a device was not 214 * registered. Unavailable devices will not get registered. 215 */ 216 struct platform_device *of_platform_device_create(struct device_node *np, 217 const char *bus_id, 218 struct device *parent) 219 { 220 return of_platform_device_create_pdata(np, bus_id, NULL, parent); 221 } 222 EXPORT_SYMBOL(of_platform_device_create); 223 224 #ifdef CONFIG_ARM_AMBA 225 static struct amba_device *of_amba_device_create(struct device_node *node, 226 const char *bus_id, 227 void *platform_data, 228 struct device *parent) 229 { 230 struct amba_device *dev; 231 const void *prop; 232 int i, ret; 233 234 pr_debug("Creating amba device %pOF\n", node); 235 236 if (!of_device_is_available(node) || 237 of_node_test_and_set_flag(node, OF_POPULATED)) 238 return NULL; 239 240 dev = amba_device_alloc(NULL, 0, 0); 241 if (!dev) 242 goto err_clear_flag; 243 244 /* setup generic device info */ 245 dev->dev.of_node = of_node_get(node); 246 dev->dev.fwnode = &node->fwnode; 247 dev->dev.parent = parent ? : &platform_bus; 248 dev->dev.platform_data = platform_data; 249 if (bus_id) 250 dev_set_name(&dev->dev, "%s", bus_id); 251 else 252 of_device_make_bus_id(&dev->dev); 253 254 /* Allow the HW Peripheral ID to be overridden */ 255 prop = of_get_property(node, "arm,primecell-periphid", NULL); 256 if (prop) 257 dev->periphid = of_read_ulong(prop, 1); 258 259 /* Decode the IRQs and address ranges */ 260 for (i = 0; i < AMBA_NR_IRQS; i++) 261 dev->irq[i] = irq_of_parse_and_map(node, i); 262 263 ret = of_address_to_resource(node, 0, &dev->res); 264 if (ret) { 265 pr_err("amba: of_address_to_resource() failed (%d) for %pOF\n", 266 ret, node); 267 goto err_free; 268 } 269 270 ret = amba_device_add(dev, &iomem_resource); 271 if (ret) { 272 pr_err("amba_device_add() failed (%d) for %pOF\n", 273 ret, node); 274 goto err_free; 275 } 276 277 return dev; 278 279 err_free: 280 amba_device_put(dev); 281 err_clear_flag: 282 of_node_clear_flag(node, OF_POPULATED); 283 return NULL; 284 } 285 #else /* CONFIG_ARM_AMBA */ 286 static struct amba_device *of_amba_device_create(struct device_node *node, 287 const char *bus_id, 288 void *platform_data, 289 struct device *parent) 290 { 291 return NULL; 292 } 293 #endif /* CONFIG_ARM_AMBA */ 294 295 /** 296 * of_devname_lookup() - Given a device node, lookup the preferred Linux name 297 */ 298 static const struct of_dev_auxdata *of_dev_lookup(const struct of_dev_auxdata *lookup, 299 struct device_node *np) 300 { 301 const struct of_dev_auxdata *auxdata; 302 struct resource res; 303 int compatible = 0; 304 305 if (!lookup) 306 return NULL; 307 308 auxdata = lookup; 309 for (; auxdata->compatible; auxdata++) { 310 if (!of_device_is_compatible(np, auxdata->compatible)) 311 continue; 312 compatible++; 313 if (!of_address_to_resource(np, 0, &res)) 314 if (res.start != auxdata->phys_addr) 315 continue; 316 pr_debug("%pOF: devname=%s\n", np, auxdata->name); 317 return auxdata; 318 } 319 320 if (!compatible) 321 return NULL; 322 323 /* Try compatible match if no phys_addr and name are specified */ 324 auxdata = lookup; 325 for (; auxdata->compatible; auxdata++) { 326 if (!of_device_is_compatible(np, auxdata->compatible)) 327 continue; 328 if (!auxdata->phys_addr && !auxdata->name) { 329 pr_debug("%pOF: compatible match\n", np); 330 return auxdata; 331 } 332 } 333 334 return NULL; 335 } 336 337 /** 338 * of_platform_bus_create() - Create a device for a node and its children. 339 * @bus: device node of the bus to instantiate 340 * @matches: match table for bus nodes 341 * @lookup: auxdata table for matching id and platform_data with device nodes 342 * @parent: parent for new device, or NULL for top level. 343 * @strict: require compatible property 344 * 345 * Creates a platform_device for the provided device_node, and optionally 346 * recursively create devices for all the child nodes. 347 */ 348 static int of_platform_bus_create(struct device_node *bus, 349 const struct of_device_id *matches, 350 const struct of_dev_auxdata *lookup, 351 struct device *parent, bool strict) 352 { 353 const struct of_dev_auxdata *auxdata; 354 struct device_node *child; 355 struct platform_device *dev; 356 const char *bus_id = NULL; 357 void *platform_data = NULL; 358 int rc = 0; 359 360 /* Make sure it has a compatible property */ 361 if (strict && (!of_get_property(bus, "compatible", NULL))) { 362 pr_debug("%s() - skipping %pOF, no compatible prop\n", 363 __func__, bus); 364 return 0; 365 } 366 367 /* Skip nodes for which we don't want to create devices */ 368 if (unlikely(of_match_node(of_skipped_node_table, bus))) { 369 pr_debug("%s() - skipping %pOF node\n", __func__, bus); 370 return 0; 371 } 372 373 if (of_node_check_flag(bus, OF_POPULATED_BUS)) { 374 pr_debug("%s() - skipping %pOF, already populated\n", 375 __func__, bus); 376 return 0; 377 } 378 379 auxdata = of_dev_lookup(lookup, bus); 380 if (auxdata) { 381 bus_id = auxdata->name; 382 platform_data = auxdata->platform_data; 383 } 384 385 if (of_device_is_compatible(bus, "arm,primecell")) { 386 /* 387 * Don't return an error here to keep compatibility with older 388 * device tree files. 389 */ 390 of_amba_device_create(bus, bus_id, platform_data, parent); 391 return 0; 392 } 393 394 dev = of_platform_device_create_pdata(bus, bus_id, platform_data, parent); 395 if (!dev || !of_match_node(matches, bus)) 396 return 0; 397 398 for_each_child_of_node(bus, child) { 399 pr_debug(" create child: %pOF\n", child); 400 rc = of_platform_bus_create(child, matches, lookup, &dev->dev, strict); 401 if (rc) { 402 of_node_put(child); 403 break; 404 } 405 } 406 of_node_set_flag(bus, OF_POPULATED_BUS); 407 return rc; 408 } 409 410 /** 411 * of_platform_bus_probe() - Probe the device-tree for platform buses 412 * @root: parent of the first level to probe or NULL for the root of the tree 413 * @matches: match table for bus nodes 414 * @parent: parent to hook devices from, NULL for toplevel 415 * 416 * Note that children of the provided root are not instantiated as devices 417 * unless the specified root itself matches the bus list and is not NULL. 418 */ 419 int of_platform_bus_probe(struct device_node *root, 420 const struct of_device_id *matches, 421 struct device *parent) 422 { 423 struct device_node *child; 424 int rc = 0; 425 426 root = root ? of_node_get(root) : of_find_node_by_path("/"); 427 if (!root) 428 return -EINVAL; 429 430 pr_debug("%s()\n", __func__); 431 pr_debug(" starting at: %pOF\n", root); 432 433 /* Do a self check of bus type, if there's a match, create children */ 434 if (of_match_node(matches, root)) { 435 rc = of_platform_bus_create(root, matches, NULL, parent, false); 436 } else for_each_child_of_node(root, child) { 437 if (!of_match_node(matches, child)) 438 continue; 439 rc = of_platform_bus_create(child, matches, NULL, parent, false); 440 if (rc) { 441 of_node_put(child); 442 break; 443 } 444 } 445 446 of_node_put(root); 447 return rc; 448 } 449 EXPORT_SYMBOL(of_platform_bus_probe); 450 451 /** 452 * of_platform_populate() - Populate platform_devices from device tree data 453 * @root: parent of the first level to probe or NULL for the root of the tree 454 * @matches: match table, NULL to use the default 455 * @lookup: auxdata table for matching id and platform_data with device nodes 456 * @parent: parent to hook devices from, NULL for toplevel 457 * 458 * Similar to of_platform_bus_probe(), this function walks the device tree 459 * and creates devices from nodes. It differs in that it follows the modern 460 * convention of requiring all device nodes to have a 'compatible' property, 461 * and it is suitable for creating devices which are children of the root 462 * node (of_platform_bus_probe will only create children of the root which 463 * are selected by the @matches argument). 464 * 465 * New board support should be using this function instead of 466 * of_platform_bus_probe(). 467 * 468 * Returns 0 on success, < 0 on failure. 469 */ 470 int of_platform_populate(struct device_node *root, 471 const struct of_device_id *matches, 472 const struct of_dev_auxdata *lookup, 473 struct device *parent) 474 { 475 struct device_node *child; 476 int rc = 0; 477 478 root = root ? of_node_get(root) : of_find_node_by_path("/"); 479 if (!root) 480 return -EINVAL; 481 482 pr_debug("%s()\n", __func__); 483 pr_debug(" starting at: %pOF\n", root); 484 485 for_each_child_of_node(root, child) { 486 rc = of_platform_bus_create(child, matches, lookup, parent, true); 487 if (rc) { 488 of_node_put(child); 489 break; 490 } 491 } 492 of_node_set_flag(root, OF_POPULATED_BUS); 493 494 of_node_put(root); 495 return rc; 496 } 497 EXPORT_SYMBOL_GPL(of_platform_populate); 498 499 int of_platform_default_populate(struct device_node *root, 500 const struct of_dev_auxdata *lookup, 501 struct device *parent) 502 { 503 return of_platform_populate(root, of_default_bus_match_table, lookup, 504 parent); 505 } 506 EXPORT_SYMBOL_GPL(of_platform_default_populate); 507 508 #ifndef CONFIG_PPC 509 static const struct of_device_id reserved_mem_matches[] = { 510 { .compatible = "qcom,rmtfs-mem" }, 511 { .compatible = "qcom,cmd-db" }, 512 { .compatible = "ramoops" }, 513 {} 514 }; 515 516 static int __init of_platform_default_populate_init(void) 517 { 518 struct device_node *node; 519 520 if (!of_have_populated_dt()) 521 return -ENODEV; 522 523 /* 524 * Handle certain compatibles explicitly, since we don't want to create 525 * platform_devices for every node in /reserved-memory with a 526 * "compatible", 527 */ 528 for_each_matching_node(node, reserved_mem_matches) 529 of_platform_device_create(node, NULL, NULL); 530 531 node = of_find_node_by_path("/firmware"); 532 if (node) { 533 of_platform_populate(node, NULL, NULL, NULL); 534 of_node_put(node); 535 } 536 537 /* Populate everything else. */ 538 of_platform_default_populate(NULL, NULL, NULL); 539 540 return 0; 541 } 542 arch_initcall_sync(of_platform_default_populate_init); 543 #endif 544 545 int of_platform_device_destroy(struct device *dev, void *data) 546 { 547 /* Do not touch devices not populated from the device tree */ 548 if (!dev->of_node || !of_node_check_flag(dev->of_node, OF_POPULATED)) 549 return 0; 550 551 /* Recurse for any nodes that were treated as busses */ 552 if (of_node_check_flag(dev->of_node, OF_POPULATED_BUS)) 553 device_for_each_child(dev, NULL, of_platform_device_destroy); 554 555 of_node_clear_flag(dev->of_node, OF_POPULATED); 556 of_node_clear_flag(dev->of_node, OF_POPULATED_BUS); 557 558 if (dev->bus == &platform_bus_type) 559 platform_device_unregister(to_platform_device(dev)); 560 #ifdef CONFIG_ARM_AMBA 561 else if (dev->bus == &amba_bustype) 562 amba_device_unregister(to_amba_device(dev)); 563 #endif 564 565 return 0; 566 } 567 EXPORT_SYMBOL_GPL(of_platform_device_destroy); 568 569 /** 570 * of_platform_depopulate() - Remove devices populated from device tree 571 * @parent: device which children will be removed 572 * 573 * Complementary to of_platform_populate(), this function removes children 574 * of the given device (and, recurrently, their children) that have been 575 * created from their respective device tree nodes (and only those, 576 * leaving others - eg. manually created - unharmed). 577 */ 578 void of_platform_depopulate(struct device *parent) 579 { 580 if (parent->of_node && of_node_check_flag(parent->of_node, OF_POPULATED_BUS)) { 581 device_for_each_child(parent, NULL, of_platform_device_destroy); 582 of_node_clear_flag(parent->of_node, OF_POPULATED_BUS); 583 } 584 } 585 EXPORT_SYMBOL_GPL(of_platform_depopulate); 586 587 static void devm_of_platform_populate_release(struct device *dev, void *res) 588 { 589 of_platform_depopulate(*(struct device **)res); 590 } 591 592 /** 593 * devm_of_platform_populate() - Populate platform_devices from device tree data 594 * @dev: device that requested to populate from device tree data 595 * 596 * Similar to of_platform_populate(), but will automatically call 597 * of_platform_depopulate() when the device is unbound from the bus. 598 * 599 * Returns 0 on success, < 0 on failure. 600 */ 601 int devm_of_platform_populate(struct device *dev) 602 { 603 struct device **ptr; 604 int ret; 605 606 if (!dev) 607 return -EINVAL; 608 609 ptr = devres_alloc(devm_of_platform_populate_release, 610 sizeof(*ptr), GFP_KERNEL); 611 if (!ptr) 612 return -ENOMEM; 613 614 ret = of_platform_populate(dev->of_node, NULL, NULL, dev); 615 if (ret) { 616 devres_free(ptr); 617 } else { 618 *ptr = dev; 619 devres_add(dev, ptr); 620 } 621 622 return ret; 623 } 624 EXPORT_SYMBOL_GPL(devm_of_platform_populate); 625 626 static int devm_of_platform_match(struct device *dev, void *res, void *data) 627 { 628 struct device **ptr = res; 629 630 if (!ptr) { 631 WARN_ON(!ptr); 632 return 0; 633 } 634 635 return *ptr == data; 636 } 637 638 /** 639 * devm_of_platform_depopulate() - Remove devices populated from device tree 640 * @dev: device that requested to depopulate from device tree data 641 * 642 * Complementary to devm_of_platform_populate(), this function removes children 643 * of the given device (and, recurrently, their children) that have been 644 * created from their respective device tree nodes (and only those, 645 * leaving others - eg. manually created - unharmed). 646 */ 647 void devm_of_platform_depopulate(struct device *dev) 648 { 649 int ret; 650 651 ret = devres_release(dev, devm_of_platform_populate_release, 652 devm_of_platform_match, dev); 653 654 WARN_ON(ret); 655 } 656 EXPORT_SYMBOL_GPL(devm_of_platform_depopulate); 657 658 #ifdef CONFIG_OF_DYNAMIC 659 static int of_platform_notify(struct notifier_block *nb, 660 unsigned long action, void *arg) 661 { 662 struct of_reconfig_data *rd = arg; 663 struct platform_device *pdev_parent, *pdev; 664 bool children_left; 665 666 switch (of_reconfig_get_state_change(action, rd)) { 667 case OF_RECONFIG_CHANGE_ADD: 668 /* verify that the parent is a bus */ 669 if (!of_node_check_flag(rd->dn->parent, OF_POPULATED_BUS)) 670 return NOTIFY_OK; /* not for us */ 671 672 /* already populated? (driver using of_populate manually) */ 673 if (of_node_check_flag(rd->dn, OF_POPULATED)) 674 return NOTIFY_OK; 675 676 /* pdev_parent may be NULL when no bus platform device */ 677 pdev_parent = of_find_device_by_node(rd->dn->parent); 678 pdev = of_platform_device_create(rd->dn, NULL, 679 pdev_parent ? &pdev_parent->dev : NULL); 680 of_dev_put(pdev_parent); 681 682 if (pdev == NULL) { 683 pr_err("%s: failed to create for '%pOF'\n", 684 __func__, rd->dn); 685 /* of_platform_device_create tosses the error code */ 686 return notifier_from_errno(-EINVAL); 687 } 688 break; 689 690 case OF_RECONFIG_CHANGE_REMOVE: 691 692 /* already depopulated? */ 693 if (!of_node_check_flag(rd->dn, OF_POPULATED)) 694 return NOTIFY_OK; 695 696 /* find our device by node */ 697 pdev = of_find_device_by_node(rd->dn); 698 if (pdev == NULL) 699 return NOTIFY_OK; /* no? not meant for us */ 700 701 /* unregister takes one ref away */ 702 of_platform_device_destroy(&pdev->dev, &children_left); 703 704 /* and put the reference of the find */ 705 of_dev_put(pdev); 706 break; 707 } 708 709 return NOTIFY_OK; 710 } 711 712 static struct notifier_block platform_of_notifier = { 713 .notifier_call = of_platform_notify, 714 }; 715 716 void of_platform_register_reconfig_notifier(void) 717 { 718 WARN_ON(of_reconfig_notifier_register(&platform_of_notifier)); 719 } 720 #endif /* CONFIG_OF_DYNAMIC */ 721 722 #endif /* CONFIG_OF_ADDRESS */ 723