1 /* 2 * Device manager 3 * 4 * Copyright (c) 2013 Google, Inc 5 * 6 * (C) Copyright 2012 7 * Pavel Herrmann <morpheus.ibis@gmail.com> 8 * 9 * SPDX-License-Identifier: GPL-2.0+ 10 */ 11 12 #include <common.h> 13 #include <fdtdec.h> 14 #include <malloc.h> 15 #include <dm/device.h> 16 #include <dm/device-internal.h> 17 #include <dm/lists.h> 18 #include <dm/platdata.h> 19 #include <dm/uclass.h> 20 #include <dm/uclass-internal.h> 21 #include <dm/util.h> 22 #include <linux/err.h> 23 #include <linux/list.h> 24 25 DECLARE_GLOBAL_DATA_PTR; 26 27 /** 28 * device_chld_unbind() - Unbind all device's children from the device 29 * 30 * On error, the function continues to unbind all children, and reports the 31 * first error. 32 * 33 * @dev: The device that is to be stripped of its children 34 * @return 0 on success, -ve on error 35 */ 36 static int device_chld_unbind(struct udevice *dev) 37 { 38 struct udevice *pos, *n; 39 int ret, saved_ret = 0; 40 41 assert(dev); 42 43 list_for_each_entry_safe(pos, n, &dev->child_head, sibling_node) { 44 ret = device_unbind(pos); 45 if (ret && !saved_ret) 46 saved_ret = ret; 47 } 48 49 return saved_ret; 50 } 51 52 /** 53 * device_chld_remove() - Stop all device's children 54 * @dev: The device whose children are to be removed 55 * @return 0 on success, -ve on error 56 */ 57 static int device_chld_remove(struct udevice *dev) 58 { 59 struct udevice *pos, *n; 60 int ret; 61 62 assert(dev); 63 64 list_for_each_entry_safe(pos, n, &dev->child_head, sibling_node) { 65 ret = device_remove(pos); 66 if (ret) 67 return ret; 68 } 69 70 return 0; 71 } 72 73 int device_bind(struct udevice *parent, struct driver *drv, const char *name, 74 void *platdata, int of_offset, struct udevice **devp) 75 { 76 struct udevice *dev; 77 struct uclass *uc; 78 int ret = 0; 79 80 *devp = NULL; 81 if (!name) 82 return -EINVAL; 83 84 ret = uclass_get(drv->id, &uc); 85 if (ret) 86 return ret; 87 88 dev = calloc(1, sizeof(struct udevice)); 89 if (!dev) 90 return -ENOMEM; 91 92 INIT_LIST_HEAD(&dev->sibling_node); 93 INIT_LIST_HEAD(&dev->child_head); 94 INIT_LIST_HEAD(&dev->uclass_node); 95 dev->platdata = platdata; 96 dev->name = name; 97 dev->of_offset = of_offset; 98 dev->parent = parent; 99 dev->driver = drv; 100 dev->uclass = uc; 101 102 /* 103 * For some devices, such as a SPI or I2C bus, the 'reg' property 104 * is a reasonable indicator of the sequence number. But if there is 105 * an alias, we use that in preference. In any case, this is just 106 * a 'requested' sequence, and will be resolved (and ->seq updated) 107 * when the device is probed. 108 */ 109 dev->seq = -1; 110 #ifdef CONFIG_OF_CONTROL 111 dev->req_seq = fdtdec_get_int(gd->fdt_blob, of_offset, "reg", -1); 112 if (!IS_ERR_VALUE(dev->req_seq)) 113 dev->req_seq &= INT_MAX; 114 if (uc->uc_drv->name && of_offset != -1) { 115 fdtdec_get_alias_seq(gd->fdt_blob, uc->uc_drv->name, of_offset, 116 &dev->req_seq); 117 } 118 #else 119 dev->req_seq = -1; 120 #endif 121 if (!dev->platdata && drv->platdata_auto_alloc_size) 122 dev->flags |= DM_FLAG_ALLOC_PDATA; 123 124 /* put dev into parent's successor list */ 125 if (parent) 126 list_add_tail(&dev->sibling_node, &parent->child_head); 127 128 ret = uclass_bind_device(dev); 129 if (ret) 130 goto fail_bind; 131 132 /* if we fail to bind we remove device from successors and free it */ 133 if (drv->bind) { 134 ret = drv->bind(dev); 135 if (ret) { 136 if (uclass_unbind_device(dev)) { 137 dm_warn("Failed to unbind dev '%s' on error path\n", 138 dev->name); 139 } 140 goto fail_bind; 141 } 142 } 143 if (parent) 144 dm_dbg("Bound device %s to %s\n", dev->name, parent->name); 145 *devp = dev; 146 147 return 0; 148 149 fail_bind: 150 list_del(&dev->sibling_node); 151 free(dev); 152 return ret; 153 } 154 155 int device_bind_by_name(struct udevice *parent, bool pre_reloc_only, 156 const struct driver_info *info, struct udevice **devp) 157 { 158 struct driver *drv; 159 160 drv = lists_driver_lookup_name(info->name); 161 if (!drv) 162 return -ENOENT; 163 if (pre_reloc_only && !(drv->flags & DM_FLAG_PRE_RELOC)) 164 return -EPERM; 165 166 return device_bind(parent, drv, info->name, (void *)info->platdata, 167 -1, devp); 168 } 169 170 int device_unbind(struct udevice *dev) 171 { 172 struct driver *drv; 173 int ret; 174 175 if (!dev) 176 return -EINVAL; 177 178 if (dev->flags & DM_FLAG_ACTIVATED) 179 return -EINVAL; 180 181 drv = dev->driver; 182 assert(drv); 183 184 if (drv->unbind) { 185 ret = drv->unbind(dev); 186 if (ret) 187 return ret; 188 } 189 190 ret = device_chld_unbind(dev); 191 if (ret) 192 return ret; 193 194 ret = uclass_unbind_device(dev); 195 if (ret) 196 return ret; 197 198 if (dev->parent) 199 list_del(&dev->sibling_node); 200 free(dev); 201 202 return 0; 203 } 204 205 /** 206 * device_free() - Free memory buffers allocated by a device 207 * @dev: Device that is to be started 208 */ 209 static void device_free(struct udevice *dev) 210 { 211 int size; 212 213 if (dev->driver->priv_auto_alloc_size) { 214 free(dev->priv); 215 dev->priv = NULL; 216 } 217 if (dev->flags & DM_FLAG_ALLOC_PDATA) { 218 free(dev->platdata); 219 dev->platdata = NULL; 220 } 221 size = dev->uclass->uc_drv->per_device_auto_alloc_size; 222 if (size) { 223 free(dev->uclass_priv); 224 dev->uclass_priv = NULL; 225 } 226 if (dev->parent) { 227 size = dev->parent->driver->per_child_auto_alloc_size; 228 if (size) { 229 free(dev->parent_priv); 230 dev->parent_priv = NULL; 231 } 232 } 233 } 234 235 int device_probe_child(struct udevice *dev, void *parent_priv) 236 { 237 struct driver *drv; 238 int size = 0; 239 int ret; 240 int seq; 241 242 if (!dev) 243 return -EINVAL; 244 245 if (dev->flags & DM_FLAG_ACTIVATED) 246 return 0; 247 248 drv = dev->driver; 249 assert(drv); 250 251 /* Allocate private data and platdata if requested */ 252 if (drv->priv_auto_alloc_size) { 253 dev->priv = calloc(1, drv->priv_auto_alloc_size); 254 if (!dev->priv) { 255 ret = -ENOMEM; 256 goto fail; 257 } 258 } 259 /* Allocate private data if requested */ 260 if (dev->flags & DM_FLAG_ALLOC_PDATA) { 261 dev->platdata = calloc(1, drv->platdata_auto_alloc_size); 262 if (!dev->platdata) { 263 ret = -ENOMEM; 264 goto fail; 265 } 266 } 267 size = dev->uclass->uc_drv->per_device_auto_alloc_size; 268 if (size) { 269 dev->uclass_priv = calloc(1, size); 270 if (!dev->uclass_priv) { 271 ret = -ENOMEM; 272 goto fail; 273 } 274 } 275 276 /* Ensure all parents are probed */ 277 if (dev->parent) { 278 size = dev->parent->driver->per_child_auto_alloc_size; 279 if (size) { 280 dev->parent_priv = calloc(1, size); 281 if (!dev->parent_priv) { 282 ret = -ENOMEM; 283 goto fail; 284 } 285 if (parent_priv) 286 memcpy(dev->parent_priv, parent_priv, size); 287 } 288 289 ret = device_probe(dev->parent); 290 if (ret) 291 goto fail; 292 } 293 294 seq = uclass_resolve_seq(dev); 295 if (seq < 0) { 296 ret = seq; 297 goto fail; 298 } 299 dev->seq = seq; 300 301 if (dev->parent && dev->parent->driver->child_pre_probe) { 302 ret = dev->parent->driver->child_pre_probe(dev); 303 if (ret) 304 goto fail; 305 } 306 307 if (drv->ofdata_to_platdata && dev->of_offset >= 0) { 308 ret = drv->ofdata_to_platdata(dev); 309 if (ret) 310 goto fail; 311 } 312 313 if (drv->probe) { 314 ret = drv->probe(dev); 315 if (ret) 316 goto fail; 317 } 318 319 dev->flags |= DM_FLAG_ACTIVATED; 320 321 ret = uclass_post_probe_device(dev); 322 if (ret) { 323 dev->flags &= ~DM_FLAG_ACTIVATED; 324 goto fail_uclass; 325 } 326 327 return 0; 328 fail_uclass: 329 if (device_remove(dev)) { 330 dm_warn("%s: Device '%s' failed to remove on error path\n", 331 __func__, dev->name); 332 } 333 fail: 334 dev->seq = -1; 335 device_free(dev); 336 337 return ret; 338 } 339 340 int device_probe(struct udevice *dev) 341 { 342 return device_probe_child(dev, NULL); 343 } 344 345 int device_remove(struct udevice *dev) 346 { 347 struct driver *drv; 348 int ret; 349 350 if (!dev) 351 return -EINVAL; 352 353 if (!(dev->flags & DM_FLAG_ACTIVATED)) 354 return 0; 355 356 drv = dev->driver; 357 assert(drv); 358 359 ret = uclass_pre_remove_device(dev); 360 if (ret) 361 return ret; 362 363 ret = device_chld_remove(dev); 364 if (ret) 365 goto err; 366 367 if (drv->remove) { 368 ret = drv->remove(dev); 369 if (ret) 370 goto err_remove; 371 } 372 373 if (dev->parent && dev->parent->driver->child_post_remove) { 374 ret = dev->parent->driver->child_post_remove(dev); 375 if (ret) { 376 dm_warn("%s: Device '%s' failed child_post_remove()", 377 __func__, dev->name); 378 } 379 } 380 381 device_free(dev); 382 383 dev->seq = -1; 384 dev->flags &= ~DM_FLAG_ACTIVATED; 385 386 return ret; 387 388 err_remove: 389 /* We can't put the children back */ 390 dm_warn("%s: Device '%s' failed to remove, but children are gone\n", 391 __func__, dev->name); 392 err: 393 ret = uclass_post_probe_device(dev); 394 if (ret) { 395 dm_warn("%s: Device '%s' failed to post_probe on error path\n", 396 __func__, dev->name); 397 } 398 399 return ret; 400 } 401 402 void *dev_get_platdata(struct udevice *dev) 403 { 404 if (!dev) { 405 dm_warn("%s: null device", __func__); 406 return NULL; 407 } 408 409 return dev->platdata; 410 } 411 412 void *dev_get_priv(struct udevice *dev) 413 { 414 if (!dev) { 415 dm_warn("%s: null device", __func__); 416 return NULL; 417 } 418 419 return dev->priv; 420 } 421 422 void *dev_get_parentdata(struct udevice *dev) 423 { 424 if (!dev) { 425 dm_warn("%s: null device", __func__); 426 return NULL; 427 } 428 429 return dev->parent_priv; 430 } 431 432 static int device_get_device_tail(struct udevice *dev, int ret, 433 struct udevice **devp) 434 { 435 if (ret) 436 return ret; 437 438 ret = device_probe(dev); 439 if (ret) 440 return ret; 441 442 *devp = dev; 443 444 return 0; 445 } 446 447 int device_get_child(struct udevice *parent, int index, struct udevice **devp) 448 { 449 struct udevice *dev; 450 451 list_for_each_entry(dev, &parent->child_head, sibling_node) { 452 if (!index--) 453 return device_get_device_tail(dev, 0, devp); 454 } 455 456 return -ENODEV; 457 } 458 459 int device_find_child_by_seq(struct udevice *parent, int seq_or_req_seq, 460 bool find_req_seq, struct udevice **devp) 461 { 462 struct udevice *dev; 463 464 *devp = NULL; 465 if (seq_or_req_seq == -1) 466 return -ENODEV; 467 468 list_for_each_entry(dev, &parent->child_head, sibling_node) { 469 if ((find_req_seq ? dev->req_seq : dev->seq) == 470 seq_or_req_seq) { 471 *devp = dev; 472 return 0; 473 } 474 } 475 476 return -ENODEV; 477 } 478 479 int device_get_child_by_seq(struct udevice *parent, int seq, 480 struct udevice **devp) 481 { 482 struct udevice *dev; 483 int ret; 484 485 *devp = NULL; 486 ret = device_find_child_by_seq(parent, seq, false, &dev); 487 if (ret == -ENODEV) { 488 /* 489 * We didn't find it in probed devices. See if there is one 490 * that will request this seq if probed. 491 */ 492 ret = device_find_child_by_seq(parent, seq, true, &dev); 493 } 494 return device_get_device_tail(dev, ret, devp); 495 } 496 497 int device_find_child_by_of_offset(struct udevice *parent, int of_offset, 498 struct udevice **devp) 499 { 500 struct udevice *dev; 501 502 *devp = NULL; 503 504 list_for_each_entry(dev, &parent->child_head, sibling_node) { 505 if (dev->of_offset == of_offset) { 506 *devp = dev; 507 return 0; 508 } 509 } 510 511 return -ENODEV; 512 } 513 514 int device_get_child_by_of_offset(struct udevice *parent, int seq, 515 struct udevice **devp) 516 { 517 struct udevice *dev; 518 int ret; 519 520 *devp = NULL; 521 ret = device_find_child_by_of_offset(parent, seq, &dev); 522 return device_get_device_tail(dev, ret, devp); 523 } 524 525 int device_find_first_child(struct udevice *parent, struct udevice **devp) 526 { 527 if (list_empty(&parent->child_head)) { 528 *devp = NULL; 529 } else { 530 *devp = list_first_entry(&parent->child_head, struct udevice, 531 sibling_node); 532 } 533 534 return 0; 535 } 536 537 int device_find_next_child(struct udevice **devp) 538 { 539 struct udevice *dev = *devp; 540 struct udevice *parent = dev->parent; 541 542 if (list_is_last(&dev->sibling_node, &parent->child_head)) { 543 *devp = NULL; 544 } else { 545 *devp = list_entry(dev->sibling_node.next, struct udevice, 546 sibling_node); 547 } 548 549 return 0; 550 } 551