1 // SPDX-License-Identifier: BSD-2-Clause 2 /* 3 * Copyright (c) 2021, Linaro Limited 4 * Copyright (c) 2021, Bootlin 5 * Copyright (c) 2021, Linaro Limited 6 * Copyright (c) 2021, STMicroelectronics 7 */ 8 9 #include <assert.h> 10 #include <config.h> 11 #include <initcall.h> 12 #include <kernel/boot.h> 13 #include <kernel/dt.h> 14 #include <kernel/dt_driver.h> 15 #include <libfdt.h> 16 #include <malloc.h> 17 #include <sys/queue.h> 18 #include <tee_api_defines_extensions.h> 19 #include <tee_api_types.h> 20 21 /* 22 * struct dt_driver_probe - Node instance in secure FDT to probe a driver for 23 * 24 * @link: List hook 25 * @nodeoffset: Node offset of device referenced in the FDT 26 * @type: One of DT_DRIVER_* or DT_DRIVER_NOTYPE. 27 * @deferrals: Driver probe deferrals count 28 * @dt_drv: Matching driver to probe if found or NULL 29 * @dm: Matching reference if applicable or NULL 30 */ 31 struct dt_driver_probe { 32 int nodeoffset; 33 enum dt_driver_type type; 34 unsigned int deferrals; 35 const struct dt_driver *dt_drv; 36 const struct dt_device_match *dm; 37 TAILQ_ENTRY(dt_driver_probe) link; 38 }; 39 40 /* 41 * struct dt_driver_provider - DT related info on probed device 42 * 43 * Saves information on the probed device so that device 44 * drivers can get resources from DT phandle and related arguments. 45 * 46 * @nodeoffset: Node offset of device referenced in the FDT 47 * @type: One of DT_DRIVER_* or DT_DRIVER_NOTYPE. 48 * @provider_cells: Cells count in the FDT used by the driver's references 49 * @get_of_device: Function to get driver's device ref from phandle data 50 * @priv_data: Driver private data passed as @get_of_device argument 51 * @link: Reference in DT driver providers list 52 */ 53 struct dt_driver_provider { 54 int nodeoffset; 55 enum dt_driver_type type; 56 unsigned int provider_cells; 57 uint32_t phandle; 58 get_of_device_func get_of_device; 59 void *priv_data; 60 SLIST_ENTRY(dt_driver_provider) link; 61 }; 62 63 /* 64 * Device driver providers are able to provide a driver specific instance 65 * related to device phandle arguments found in the secure embedded FDT. 66 */ 67 static SLIST_HEAD(, dt_driver_provider) dt_driver_provider_list = 68 SLIST_HEAD_INITIALIZER(dt_driver_provider_list); 69 70 /* FDT nodes for which a matching driver is to be probed */ 71 static TAILQ_HEAD(dt_driver_probe_head, dt_driver_probe) dt_driver_probe_list = 72 TAILQ_HEAD_INITIALIZER(dt_driver_probe_list); 73 74 /* FDT nodes for which a matching driver has been successfully probed */ 75 static TAILQ_HEAD(, dt_driver_probe) dt_driver_ready_list = 76 TAILQ_HEAD_INITIALIZER(dt_driver_ready_list); 77 78 /* List of the nodes for which a compatible driver but reported a failure */ 79 static TAILQ_HEAD(, dt_driver_probe) dt_driver_failed_list = 80 TAILQ_HEAD_INITIALIZER(dt_driver_failed_list); 81 82 /* Flag enabled when a new node (possibly typed) is added in the probe list */ 83 static bool added_node; 84 85 /* Resolve drivers dependencies on core crypto layer */ 86 static bool tee_crypt_is_ready; 87 88 void dt_driver_crypt_init_complete(void) 89 { 90 assert(!tee_crypt_is_ready); 91 tee_crypt_is_ready = true; 92 } 93 94 TEE_Result dt_driver_get_crypto(void) 95 { 96 if (tee_crypt_is_ready) 97 return TEE_SUCCESS; 98 else 99 return TEE_ERROR_DEFER_DRIVER_INIT; 100 } 101 102 static void assert_type_is_valid(enum dt_driver_type type) 103 { 104 switch (type) { 105 case DT_DRIVER_NOTYPE: 106 case DT_DRIVER_UART: 107 case DT_DRIVER_CLK: 108 return; 109 default: 110 assert(0); 111 } 112 } 113 114 /* 115 * Driver provider registering API functions 116 */ 117 118 TEE_Result dt_driver_register_provider(const void *fdt, int nodeoffset, 119 get_of_device_func get_of_device, 120 void *priv, enum dt_driver_type type) 121 { 122 struct dt_driver_provider *prv = NULL; 123 int provider_cells = 0; 124 uint32_t phandle = 0; 125 126 assert_type_is_valid(type); 127 128 provider_cells = fdt_get_dt_driver_cells(fdt, nodeoffset, type); 129 if (provider_cells < 0) { 130 DMSG("Failed to find provider cells: %d", provider_cells); 131 return TEE_ERROR_GENERIC; 132 } 133 134 phandle = fdt_get_phandle(fdt, nodeoffset); 135 if (!phandle || phandle == (uint32_t)-1) { 136 DMSG("Failed to find provide phandle"); 137 return TEE_ERROR_GENERIC; 138 } 139 140 prv = calloc(1, sizeof(*prv)); 141 if (!prv) 142 return TEE_ERROR_OUT_OF_MEMORY; 143 144 prv->nodeoffset = nodeoffset; 145 prv->type = type; 146 prv->provider_cells = provider_cells; 147 prv->phandle = phandle; 148 prv->get_of_device = get_of_device; 149 prv->priv_data = priv; 150 151 SLIST_INSERT_HEAD(&dt_driver_provider_list, prv, link); 152 153 return TEE_SUCCESS; 154 } 155 156 /* 157 * Helper functions for dt_drivers querying driver provider information 158 */ 159 160 int fdt_get_dt_driver_cells(const void *fdt, int nodeoffset, 161 enum dt_driver_type type) 162 { 163 const char *cells_name = NULL; 164 const fdt32_t *c = NULL; 165 int len = 0; 166 167 switch (type) { 168 case DT_DRIVER_CLK: 169 cells_name = "#clock-cells"; 170 break; 171 default: 172 panic(); 173 } 174 175 c = fdt_getprop(fdt, nodeoffset, cells_name, &len); 176 if (!c) 177 return len; 178 179 if (len != sizeof(*c)) 180 return -FDT_ERR_BADNCELLS; 181 182 return fdt32_to_cpu(*c); 183 } 184 185 unsigned int dt_driver_provider_cells(struct dt_driver_provider *prv) 186 { 187 return prv->provider_cells; 188 } 189 190 struct dt_driver_provider * 191 dt_driver_get_provider_by_node(int nodeoffset, enum dt_driver_type type) 192 { 193 struct dt_driver_provider *prv = NULL; 194 195 SLIST_FOREACH(prv, &dt_driver_provider_list, link) 196 if (prv->nodeoffset == nodeoffset && prv->type == type) 197 return prv; 198 199 return NULL; 200 } 201 202 struct dt_driver_provider * 203 dt_driver_get_provider_by_phandle(uint32_t phandle, enum dt_driver_type type) 204 { 205 struct dt_driver_provider *prv = NULL; 206 207 SLIST_FOREACH(prv, &dt_driver_provider_list, link) 208 if (prv->phandle == phandle && prv->type == type) 209 return prv; 210 211 return NULL; 212 } 213 214 static void *device_from_provider_prop(struct dt_driver_provider *prv, 215 const uint32_t *prop, 216 TEE_Result *res) 217 { 218 struct dt_driver_phandle_args *pargs = NULL; 219 unsigned int n = 0; 220 void *device = NULL; 221 222 pargs = calloc(1, prv->provider_cells * sizeof(uint32_t *) + 223 sizeof(*pargs)); 224 if (!pargs) { 225 *res = TEE_ERROR_OUT_OF_MEMORY; 226 return NULL; 227 } 228 229 pargs->args_count = prv->provider_cells; 230 for (n = 0; n < prv->provider_cells; n++) 231 pargs->args[n] = fdt32_to_cpu(prop[n + 1]); 232 233 device = prv->get_of_device(pargs, prv->priv_data, res); 234 235 free(pargs); 236 237 return device; 238 } 239 240 void *dt_driver_device_from_node_idx_prop(const char *prop_name, 241 const void *fdt, int nodeoffset, 242 unsigned int prop_idx, 243 enum dt_driver_type type, 244 TEE_Result *res) 245 { 246 int len = 0; 247 int idx = 0; 248 int idx32 = 0; 249 int prv_cells = 0; 250 uint32_t phandle = 0; 251 const uint32_t *prop = NULL; 252 struct dt_driver_provider *prv = NULL; 253 254 prop = fdt_getprop(fdt, nodeoffset, prop_name, &len); 255 if (!prop) { 256 DMSG("Property %s missing in node %s", prop_name, 257 fdt_get_name(fdt, nodeoffset, NULL)); 258 *res = TEE_ERROR_GENERIC; 259 return NULL; 260 } 261 262 while (idx < len) { 263 idx32 = idx / sizeof(uint32_t); 264 phandle = fdt32_to_cpu(prop[idx32]); 265 266 prv = dt_driver_get_provider_by_phandle(phandle, type); 267 if (!prv) { 268 /* No provider registered yet */ 269 *res = TEE_ERROR_DEFER_DRIVER_INIT; 270 return NULL; 271 } 272 273 prv_cells = dt_driver_provider_cells(prv); 274 if (prop_idx) { 275 prop_idx--; 276 idx += sizeof(phandle) + prv_cells * sizeof(uint32_t); 277 continue; 278 } 279 280 return device_from_provider_prop(prv, prop + idx32, res); 281 } 282 283 *res = TEE_ERROR_GENERIC; 284 return NULL; 285 } 286 287 static unsigned int __maybe_unused probe_list_count(void) 288 { 289 struct dt_driver_probe *elt = NULL; 290 unsigned int count = 0; 291 292 TAILQ_FOREACH(elt, &dt_driver_probe_list, link) 293 count++; 294 295 return count; 296 } 297 298 static void __maybe_unused print_probe_list(const void *fdt __maybe_unused) 299 { 300 struct dt_driver_probe *elt = NULL; 301 302 DMSG("Probe list: %u elements", probe_list_count()); 303 304 TAILQ_FOREACH(elt, &dt_driver_probe_list, link) 305 DMSG("- Driver %s probes on node %s", 306 elt->dt_drv->name, 307 fdt_get_name(fdt, elt->nodeoffset, NULL)); 308 309 DMSG("Probe list end"); 310 } 311 312 /* 313 * Probe element: push to ready list if succeeds, push to probe list if probe 314 * if deferred, panic with an error trace otherwise. 315 */ 316 static TEE_Result probe_driver_node(const void *fdt, 317 struct dt_driver_probe *elt) 318 { 319 TEE_Result res = TEE_ERROR_GENERIC; 320 const char __maybe_unused *drv_name = NULL; 321 const char __maybe_unused *node_name = NULL; 322 323 node_name = fdt_get_name(fdt, elt->nodeoffset, NULL); 324 drv_name = elt->dt_drv->name; 325 326 if (!elt->dt_drv->probe) { 327 DMSG("No probe operator for driver %s, skipped", drv_name); 328 return TEE_SUCCESS; 329 } 330 331 FMSG("Probing %s on node %s", drv_name, node_name); 332 333 res = elt->dt_drv->probe(fdt, elt->nodeoffset, elt->dm->compat_data); 334 switch (res) { 335 case TEE_SUCCESS: 336 TAILQ_INSERT_HEAD(&dt_driver_ready_list, elt, link); 337 338 DMSG("element: %s on node %s initialized", drv_name, node_name); 339 break; 340 case TEE_ERROR_DEFER_DRIVER_INIT: 341 elt->deferrals++; 342 TAILQ_INSERT_TAIL(&dt_driver_probe_list, elt, link); 343 344 DMSG("element: %s on node %s deferred %u time(s)", drv_name, 345 node_name, elt->deferrals); 346 break; 347 default: 348 TAILQ_INSERT_HEAD(&dt_driver_failed_list, elt, link); 349 350 EMSG("Failed to probe %s on node %s: %#"PRIx32, 351 drv_name, node_name, res); 352 break; 353 } 354 355 return res; 356 } 357 358 static TEE_Result alloc_elt_and_probe(const void *fdt, int node, 359 const struct dt_driver *dt_drv, 360 const struct dt_device_match *dm) 361 { 362 struct dt_driver_probe *elt = NULL; 363 364 /* Will be freed when lists are released */ 365 elt = calloc(1, sizeof(*elt)); 366 if (!elt) 367 return TEE_ERROR_OUT_OF_MEMORY; 368 369 elt->nodeoffset = node; 370 elt->dt_drv = dt_drv; 371 elt->dm = dm; 372 elt->type = dt_drv->type; 373 374 return probe_driver_node(fdt, elt); 375 } 376 377 /* Lookup a compatible driver, possibly of a specific @type, for the FDT node */ 378 static TEE_Result probe_device_by_compat(const void *fdt, int node, 379 const char *compat, 380 enum dt_driver_type type) 381 { 382 const struct dt_driver *drv = NULL; 383 const struct dt_device_match *dm = NULL; 384 385 for_each_dt_driver(drv) { 386 if (drv->type != type) 387 continue; 388 389 for (dm = drv->match_table; dm && dm->compatible; dm++) 390 if (strcmp(dm->compatible, compat) == 0) 391 return alloc_elt_and_probe(fdt, node, drv, dm); 392 } 393 394 return TEE_ERROR_ITEM_NOT_FOUND; 395 } 396 397 /* 398 * Lookup the best matching compatible driver, possibly of a specific @type, 399 * for the FDT node. 400 */ 401 TEE_Result dt_driver_probe_device_by_node(const void *fdt, int nodeoffset, 402 enum dt_driver_type type) 403 { 404 int idx = 0; 405 int len = 0; 406 int count = 0; 407 const char *compat = NULL; 408 TEE_Result res = TEE_ERROR_GENERIC; 409 410 assert_type_is_valid(type); 411 412 count = fdt_stringlist_count(fdt, nodeoffset, "compatible"); 413 if (count < 0) 414 return TEE_ERROR_ITEM_NOT_FOUND; 415 416 for (idx = 0; idx < count; idx++) { 417 compat = fdt_stringlist_get(fdt, nodeoffset, "compatible", 418 idx, &len); 419 if (!compat) 420 return TEE_ERROR_GENERIC; 421 422 res = probe_device_by_compat(fdt, nodeoffset, compat, type); 423 424 if (res != TEE_ERROR_ITEM_NOT_FOUND) 425 return res; 426 } 427 428 return TEE_ERROR_ITEM_NOT_FOUND; 429 } 430 431 static TEE_Result process_probe_list(const void *fdt) 432 { 433 struct dt_driver_probe *elt = NULL; 434 struct dt_driver_probe *prev = NULL; 435 unsigned int __maybe_unused loop_count = 0; 436 unsigned int __maybe_unused deferral_loop_count = 0; 437 bool __maybe_unused one_deferred = false; 438 bool one_probed_ok = false; 439 440 do { 441 loop_count++; 442 FMSG("Probe loop %u after %u for deferral(s)", loop_count, 443 deferral_loop_count); 444 445 /* Hack here for TRACE_DEBUG messages on probe list elements */ 446 if (TRACE_LEVEL >= TRACE_FLOW) 447 print_probe_list(fdt); 448 449 if (TAILQ_EMPTY(&dt_driver_probe_list)) 450 return TEE_SUCCESS; 451 452 /* 453 * Probe from current end to top. Deferred probed node are 454 * pushed back after current tail for the next probe round. 455 * Reset probe result flags and see status after probe round. 456 */ 457 one_deferred = false; 458 one_probed_ok = false; 459 added_node = false; 460 461 TAILQ_FOREACH_REVERSE_SAFE(elt, &dt_driver_probe_list, 462 dt_driver_probe_head, link, prev) { 463 TAILQ_REMOVE(&dt_driver_probe_list, elt, link); 464 465 switch (probe_driver_node(fdt, elt)) { 466 case TEE_SUCCESS: 467 one_probed_ok = true; 468 break; 469 case TEE_ERROR_DEFER_DRIVER_INIT: 470 one_deferred = true; 471 break; 472 default: 473 break; 474 } 475 } 476 477 if (one_deferred) 478 deferral_loop_count++; 479 480 } while (added_node || one_probed_ok); 481 482 EMSG("Panic on unresolved dependencies after %u rounds, %u deferred:", 483 loop_count, deferral_loop_count); 484 485 TAILQ_FOREACH(elt, &dt_driver_probe_list, link) 486 EMSG("- Pending: driver %s on node %s", elt->dt_drv->name, 487 fdt_get_name(fdt, elt->nodeoffset, NULL)); 488 489 TAILQ_FOREACH(elt, &dt_driver_failed_list, link) 490 EMSG("- Failed: driver %s on node %s", elt->dt_drv->name, 491 fdt_get_name(fdt, elt->nodeoffset, NULL)); 492 493 panic(); 494 } 495 496 static int driver_probe_compare(struct dt_driver_probe *candidate, 497 struct dt_driver_probe *elt) 498 { 499 if (candidate->nodeoffset != elt->nodeoffset || 500 candidate->type != elt->type) 501 return 1; 502 503 assert(elt->dt_drv == candidate->dt_drv); 504 return 0; 505 } 506 507 /* 508 * Return TEE_SUCCESS if compatible found 509 * TEE_ERROR_OUT_OF_MEMORY if heap is exhausted 510 */ 511 static TEE_Result add_node_to_probe(const void *fdt, int node, 512 const struct dt_driver *dt_drv, 513 const struct dt_device_match *dm) 514 { 515 const char __maybe_unused *node_name = fdt_get_name(fdt, node, NULL); 516 const char __maybe_unused *drv_name = dt_drv->name; 517 struct dt_driver_probe *elt = NULL; 518 struct dt_driver_probe elt_new = { 519 .dm = dm, 520 .dt_drv = dt_drv, 521 .nodeoffset = node, 522 .type = dt_drv->type, 523 }; 524 525 /* If node/type found in probe list or ready list, nothing to do */ 526 TAILQ_FOREACH(elt, &dt_driver_probe_list, link) 527 if (!driver_probe_compare(&elt_new, elt)) 528 return TEE_SUCCESS; 529 530 TAILQ_FOREACH(elt, &dt_driver_ready_list, link) 531 if (!driver_probe_compare(&elt_new, elt)) 532 return TEE_SUCCESS; 533 534 elt = malloc(sizeof(*elt)); 535 if (!elt) 536 return TEE_ERROR_OUT_OF_MEMORY; 537 538 DMSG("element: %s on node %s", node_name, drv_name); 539 540 memcpy(elt, &elt_new, sizeof(*elt)); 541 542 added_node = true; 543 544 TAILQ_INSERT_TAIL(&dt_driver_probe_list, elt, link); 545 546 /* Hack here for TRACE_DEBUG messages on current probe list elements */ 547 if (TRACE_LEVEL >= TRACE_FLOW) 548 print_probe_list(fdt); 549 550 return TEE_SUCCESS; 551 } 552 553 /* 554 * Add a node to the probe list if a dt_driver matches target compatible. 555 * 556 * If @type is DT_DRIVER_ANY, probe list can hold only 1 driver to probe for 557 * the node. A node may probe several drivers if have a unique driver type. 558 * 559 * Return TEE_SUCCESS if compatible found 560 * TEE_ERROR_ITEM_NOT_FOUND if no matching driver 561 * TEE_ERROR_OUT_OF_MEMORY if heap is exhausted 562 */ 563 static TEE_Result add_probe_node_by_compat(const void *fdt, int node, 564 const char *compat) 565 { 566 TEE_Result res = TEE_ERROR_ITEM_NOT_FOUND; 567 const struct dt_driver *dt_drv = NULL; 568 const struct dt_device_match *dm = NULL; 569 uint32_t found_types = 0; 570 571 for_each_dt_driver(dt_drv) { 572 for (dm = dt_drv->match_table; dm && dm->compatible; dm++) { 573 if (strcmp(dm->compatible, compat) == 0) { 574 assert(dt_drv->type < 32); 575 576 res = add_node_to_probe(fdt, node, dt_drv, dm); 577 if (res) 578 return res; 579 580 if (found_types & BIT(dt_drv->type)) { 581 EMSG("Driver %s multi hit on type %u", 582 dt_drv->name, dt_drv->type); 583 panic(); 584 } 585 found_types |= BIT(dt_drv->type); 586 587 /* Matching found for this driver, try next */ 588 break; 589 } 590 } 591 } 592 593 return res; 594 } 595 596 /* 597 * Add the node to the probe list if matching compatible drivers are found. 598 * Follow node's compatible property list ordering to find matching driver. 599 */ 600 TEE_Result dt_driver_maybe_add_probe_node(const void *fdt, int node) 601 { 602 int idx = 0; 603 int len = 0; 604 int count = 0; 605 const char *compat = NULL; 606 TEE_Result res = TEE_ERROR_GENERIC; 607 608 if (_fdt_get_status(fdt, node) == DT_STATUS_DISABLED) 609 return TEE_SUCCESS; 610 611 count = fdt_stringlist_count(fdt, node, "compatible"); 612 if (count < 0) 613 return TEE_SUCCESS; 614 615 for (idx = 0; idx < count; idx++) { 616 compat = fdt_stringlist_get(fdt, node, "compatible", idx, &len); 617 assert(compat && len > 0); 618 619 res = add_probe_node_by_compat(fdt, node, compat); 620 621 /* Stop lookup if something was found */ 622 if (res != TEE_ERROR_ITEM_NOT_FOUND) 623 return res; 624 } 625 626 return TEE_SUCCESS; 627 } 628 629 static void parse_node(const void *fdt, int node) 630 { 631 TEE_Result __maybe_unused res = TEE_ERROR_GENERIC; 632 int subnode = 0; 633 634 fdt_for_each_subnode(subnode, fdt, node) { 635 res = dt_driver_maybe_add_probe_node(fdt, subnode); 636 if (res) { 637 EMSG("Failed on node %s with %#"PRIx32, 638 fdt_get_name(fdt, subnode, NULL), res); 639 panic(); 640 } 641 642 /* 643 * Rescursively parse the FDT, skipping disabled nodes. 644 * FDT is expected reliable and core shall have sufficient 645 * stack depth to possibly parse all DT nodes. 646 */ 647 if (IS_ENABLED(CFG_DRIVERS_DT_RECURSIVE_PROBE)) { 648 if (_fdt_get_status(fdt, subnode) == DT_STATUS_DISABLED) 649 continue; 650 651 parse_node(fdt, subnode); 652 } 653 } 654 } 655 656 /* 657 * Parse FDT for nodes and save in probe list the node for which a dt_driver 658 * matches node's compatible property. 659 */ 660 static TEE_Result probe_dt_drivers(void) 661 { 662 const void *fdt = NULL; 663 664 if (!IS_ENABLED(CFG_EMBED_DTB)) 665 return TEE_SUCCESS; 666 667 fdt = get_embedded_dt(); 668 assert(fdt); 669 670 parse_node(fdt, fdt_path_offset(fdt, "/")); 671 672 return process_probe_list(fdt); 673 } 674 675 driver_init(probe_dt_drivers); 676 677 static TEE_Result release_probe_lists(void) 678 { 679 struct dt_driver_probe *elt = NULL; 680 struct dt_driver_probe *next = NULL; 681 struct dt_driver_provider *prov = NULL; 682 struct dt_driver_provider *next_prov = NULL; 683 const void * __maybe_unused fdt = NULL; 684 685 if (!IS_ENABLED(CFG_EMBED_DTB)) 686 return TEE_SUCCESS; 687 688 fdt = get_embedded_dt(); 689 690 assert(fdt && TAILQ_EMPTY(&dt_driver_probe_list)); 691 692 TAILQ_FOREACH_SAFE(elt, &dt_driver_ready_list, link, next) 693 free(elt); 694 695 TAILQ_FOREACH_SAFE(elt, &dt_driver_failed_list, link, next) 696 free(elt); 697 698 SLIST_FOREACH_SAFE(prov, &dt_driver_provider_list, link, next_prov) 699 free(prov); 700 701 return TEE_SUCCESS; 702 } 703 704 release_init_resource(release_probe_lists); 705 706 /* 707 * Simple bus support: handy to parse subnodes 708 */ 709 static TEE_Result simple_bus_probe(const void *fdt, int node, 710 const void *compat_data __unused) 711 { 712 TEE_Result res = TEE_ERROR_GENERIC; 713 int subnode = 0; 714 715 fdt_for_each_subnode(subnode, fdt, node) { 716 res = dt_driver_maybe_add_probe_node(fdt, subnode); 717 if (res) { 718 EMSG("Failed on node %s with %#"PRIx32, 719 fdt_get_name(fdt, subnode, NULL), res); 720 panic(); 721 } 722 } 723 724 return TEE_SUCCESS; 725 } 726 727 static const struct dt_device_match simple_bus_match_table[] = { 728 { .compatible = "simple-bus" }, 729 { } 730 }; 731 732 const struct dt_driver simple_bus_dt_driver __dt_driver = { 733 .name = "simple-bus", 734 .match_table = simple_bus_match_table, 735 .probe = simple_bus_probe, 736 }; 737