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 (uc->uc_drv->name && of_offset != -1) { 113 fdtdec_get_alias_seq(gd->fdt_blob, uc->uc_drv->name, of_offset, 114 &dev->req_seq); 115 } 116 #else 117 dev->req_seq = -1; 118 #endif 119 if (!dev->platdata && drv->platdata_auto_alloc_size) 120 dev->flags |= DM_FLAG_ALLOC_PDATA; 121 122 /* put dev into parent's successor list */ 123 if (parent) 124 list_add_tail(&dev->sibling_node, &parent->child_head); 125 126 ret = uclass_bind_device(dev); 127 if (ret) 128 goto fail_bind; 129 130 /* if we fail to bind we remove device from successors and free it */ 131 if (drv->bind) { 132 ret = drv->bind(dev); 133 if (ret) { 134 if (uclass_unbind_device(dev)) { 135 dm_warn("Failed to unbind dev '%s' on error path\n", 136 dev->name); 137 } 138 goto fail_bind; 139 } 140 } 141 if (parent) 142 dm_dbg("Bound device %s to %s\n", dev->name, parent->name); 143 *devp = dev; 144 145 return 0; 146 147 fail_bind: 148 list_del(&dev->sibling_node); 149 free(dev); 150 return ret; 151 } 152 153 int device_bind_by_name(struct udevice *parent, bool pre_reloc_only, 154 const struct driver_info *info, struct udevice **devp) 155 { 156 struct driver *drv; 157 158 drv = lists_driver_lookup_name(info->name); 159 if (!drv) 160 return -ENOENT; 161 if (pre_reloc_only && !(drv->flags & DM_FLAG_PRE_RELOC)) 162 return -EPERM; 163 164 return device_bind(parent, drv, info->name, (void *)info->platdata, 165 -1, devp); 166 } 167 168 int device_unbind(struct udevice *dev) 169 { 170 struct driver *drv; 171 int ret; 172 173 if (!dev) 174 return -EINVAL; 175 176 if (dev->flags & DM_FLAG_ACTIVATED) 177 return -EINVAL; 178 179 drv = dev->driver; 180 assert(drv); 181 182 if (drv->unbind) { 183 ret = drv->unbind(dev); 184 if (ret) 185 return ret; 186 } 187 188 ret = device_chld_unbind(dev); 189 if (ret) 190 return ret; 191 192 ret = uclass_unbind_device(dev); 193 if (ret) 194 return ret; 195 196 if (dev->parent) 197 list_del(&dev->sibling_node); 198 free(dev); 199 200 return 0; 201 } 202 203 /** 204 * device_free() - Free memory buffers allocated by a device 205 * @dev: Device that is to be started 206 */ 207 static void device_free(struct udevice *dev) 208 { 209 int size; 210 211 if (dev->driver->priv_auto_alloc_size) { 212 free(dev->priv); 213 dev->priv = NULL; 214 } 215 if (dev->flags & DM_FLAG_ALLOC_PDATA) { 216 free(dev->platdata); 217 dev->platdata = NULL; 218 } 219 size = dev->uclass->uc_drv->per_device_auto_alloc_size; 220 if (size) { 221 free(dev->uclass_priv); 222 dev->uclass_priv = NULL; 223 } 224 if (dev->parent) { 225 size = dev->parent->driver->per_child_auto_alloc_size; 226 if (size) { 227 free(dev->parent_priv); 228 dev->parent_priv = NULL; 229 } 230 } 231 } 232 233 int device_probe(struct udevice *dev) 234 { 235 struct driver *drv; 236 int size = 0; 237 int ret; 238 int seq; 239 240 if (!dev) 241 return -EINVAL; 242 243 if (dev->flags & DM_FLAG_ACTIVATED) 244 return 0; 245 246 drv = dev->driver; 247 assert(drv); 248 249 /* Allocate private data and platdata if requested */ 250 if (drv->priv_auto_alloc_size) { 251 dev->priv = calloc(1, drv->priv_auto_alloc_size); 252 if (!dev->priv) { 253 ret = -ENOMEM; 254 goto fail; 255 } 256 } 257 /* Allocate private data if requested */ 258 if (dev->flags & DM_FLAG_ALLOC_PDATA) { 259 dev->platdata = calloc(1, drv->platdata_auto_alloc_size); 260 if (!dev->platdata) { 261 ret = -ENOMEM; 262 goto fail; 263 } 264 } 265 size = dev->uclass->uc_drv->per_device_auto_alloc_size; 266 if (size) { 267 dev->uclass_priv = calloc(1, size); 268 if (!dev->uclass_priv) { 269 ret = -ENOMEM; 270 goto fail; 271 } 272 } 273 274 /* Ensure all parents are probed */ 275 if (dev->parent) { 276 size = dev->parent->driver->per_child_auto_alloc_size; 277 if (size) { 278 dev->parent_priv = calloc(1, size); 279 if (!dev->parent_priv) { 280 ret = -ENOMEM; 281 goto fail; 282 } 283 } 284 285 ret = device_probe(dev->parent); 286 if (ret) 287 goto fail; 288 } 289 290 seq = uclass_resolve_seq(dev); 291 if (seq < 0) { 292 ret = seq; 293 goto fail; 294 } 295 dev->seq = seq; 296 297 if (dev->parent && dev->parent->driver->child_pre_probe) { 298 ret = dev->parent->driver->child_pre_probe(dev); 299 if (ret) 300 goto fail; 301 } 302 303 if (drv->ofdata_to_platdata && dev->of_offset >= 0) { 304 ret = drv->ofdata_to_platdata(dev); 305 if (ret) 306 goto fail; 307 } 308 309 if (drv->probe) { 310 ret = drv->probe(dev); 311 if (ret) 312 goto fail; 313 } 314 315 dev->flags |= DM_FLAG_ACTIVATED; 316 317 ret = uclass_post_probe_device(dev); 318 if (ret) { 319 dev->flags &= ~DM_FLAG_ACTIVATED; 320 goto fail_uclass; 321 } 322 323 return 0; 324 fail_uclass: 325 if (device_remove(dev)) { 326 dm_warn("%s: Device '%s' failed to remove on error path\n", 327 __func__, dev->name); 328 } 329 fail: 330 dev->seq = -1; 331 device_free(dev); 332 333 return ret; 334 } 335 336 int device_remove(struct udevice *dev) 337 { 338 struct driver *drv; 339 int ret; 340 341 if (!dev) 342 return -EINVAL; 343 344 if (!(dev->flags & DM_FLAG_ACTIVATED)) 345 return 0; 346 347 drv = dev->driver; 348 assert(drv); 349 350 ret = uclass_pre_remove_device(dev); 351 if (ret) 352 return ret; 353 354 ret = device_chld_remove(dev); 355 if (ret) 356 goto err; 357 358 if (drv->remove) { 359 ret = drv->remove(dev); 360 if (ret) 361 goto err_remove; 362 } 363 364 if (dev->parent && dev->parent->driver->child_post_remove) { 365 ret = dev->parent->driver->child_post_remove(dev); 366 if (ret) { 367 dm_warn("%s: Device '%s' failed child_post_remove()", 368 __func__, dev->name); 369 } 370 } 371 372 device_free(dev); 373 374 dev->seq = -1; 375 dev->flags &= ~DM_FLAG_ACTIVATED; 376 377 return ret; 378 379 err_remove: 380 /* We can't put the children back */ 381 dm_warn("%s: Device '%s' failed to remove, but children are gone\n", 382 __func__, dev->name); 383 err: 384 ret = uclass_post_probe_device(dev); 385 if (ret) { 386 dm_warn("%s: Device '%s' failed to post_probe on error path\n", 387 __func__, dev->name); 388 } 389 390 return ret; 391 } 392 393 void *dev_get_platdata(struct udevice *dev) 394 { 395 if (!dev) { 396 dm_warn("%s: null device", __func__); 397 return NULL; 398 } 399 400 return dev->platdata; 401 } 402 403 void *dev_get_priv(struct udevice *dev) 404 { 405 if (!dev) { 406 dm_warn("%s: null device", __func__); 407 return NULL; 408 } 409 410 return dev->priv; 411 } 412 413 void *dev_get_parentdata(struct udevice *dev) 414 { 415 if (!dev) { 416 dm_warn("%s: null device", __func__); 417 return NULL; 418 } 419 420 return dev->parent_priv; 421 } 422 423 static int device_get_device_tail(struct udevice *dev, int ret, 424 struct udevice **devp) 425 { 426 if (ret) 427 return ret; 428 429 ret = device_probe(dev); 430 if (ret) 431 return ret; 432 433 *devp = dev; 434 435 return 0; 436 } 437 438 int device_get_child(struct udevice *parent, int index, struct udevice **devp) 439 { 440 struct udevice *dev; 441 442 list_for_each_entry(dev, &parent->child_head, sibling_node) { 443 if (!index--) 444 return device_get_device_tail(dev, 0, devp); 445 } 446 447 return -ENODEV; 448 } 449 450 int device_find_child_by_seq(struct udevice *parent, int seq_or_req_seq, 451 bool find_req_seq, struct udevice **devp) 452 { 453 struct udevice *dev; 454 455 *devp = NULL; 456 if (seq_or_req_seq == -1) 457 return -ENODEV; 458 459 list_for_each_entry(dev, &parent->child_head, sibling_node) { 460 if ((find_req_seq ? dev->req_seq : dev->seq) == 461 seq_or_req_seq) { 462 *devp = dev; 463 return 0; 464 } 465 } 466 467 return -ENODEV; 468 } 469 470 int device_get_child_by_seq(struct udevice *parent, int seq, 471 struct udevice **devp) 472 { 473 struct udevice *dev; 474 int ret; 475 476 *devp = NULL; 477 ret = device_find_child_by_seq(parent, seq, false, &dev); 478 if (ret == -ENODEV) { 479 /* 480 * We didn't find it in probed devices. See if there is one 481 * that will request this seq if probed. 482 */ 483 ret = device_find_child_by_seq(parent, seq, true, &dev); 484 } 485 return device_get_device_tail(dev, ret, devp); 486 } 487 488 int device_find_child_by_of_offset(struct udevice *parent, int of_offset, 489 struct udevice **devp) 490 { 491 struct udevice *dev; 492 493 *devp = NULL; 494 495 list_for_each_entry(dev, &parent->child_head, sibling_node) { 496 if (dev->of_offset == of_offset) { 497 *devp = dev; 498 return 0; 499 } 500 } 501 502 return -ENODEV; 503 } 504 505 int device_get_child_by_of_offset(struct udevice *parent, int seq, 506 struct udevice **devp) 507 { 508 struct udevice *dev; 509 int ret; 510 511 *devp = NULL; 512 ret = device_find_child_by_of_offset(parent, seq, &dev); 513 return device_get_device_tail(dev, ret, devp); 514 } 515