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->req_seq = fdtdec_get_int(gd->fdt_blob, of_offset, "reg", -1); 110 dev->seq = -1; 111 if (uc->uc_drv->name && of_offset != -1) { 112 fdtdec_get_alias_seq(gd->fdt_blob, uc->uc_drv->name, of_offset, 113 &dev->req_seq); 114 } 115 116 if (!dev->platdata && drv->platdata_auto_alloc_size) 117 dev->flags |= DM_FLAG_ALLOC_PDATA; 118 119 /* put dev into parent's successor list */ 120 if (parent) 121 list_add_tail(&dev->sibling_node, &parent->child_head); 122 123 ret = uclass_bind_device(dev); 124 if (ret) 125 goto fail_bind; 126 127 /* if we fail to bind we remove device from successors and free it */ 128 if (drv->bind) { 129 ret = drv->bind(dev); 130 if (ret) { 131 if (uclass_unbind_device(dev)) { 132 dm_warn("Failed to unbind dev '%s' on error path\n", 133 dev->name); 134 } 135 goto fail_bind; 136 } 137 } 138 if (parent) 139 dm_dbg("Bound device %s to %s\n", dev->name, parent->name); 140 *devp = dev; 141 142 return 0; 143 144 fail_bind: 145 list_del(&dev->sibling_node); 146 free(dev); 147 return ret; 148 } 149 150 int device_bind_by_name(struct udevice *parent, bool pre_reloc_only, 151 const struct driver_info *info, struct udevice **devp) 152 { 153 struct driver *drv; 154 155 drv = lists_driver_lookup_name(info->name); 156 if (!drv) 157 return -ENOENT; 158 if (pre_reloc_only && !(drv->flags & DM_FLAG_PRE_RELOC)) 159 return -EPERM; 160 161 return device_bind(parent, drv, info->name, (void *)info->platdata, 162 -1, devp); 163 } 164 165 int device_unbind(struct udevice *dev) 166 { 167 struct driver *drv; 168 int ret; 169 170 if (!dev) 171 return -EINVAL; 172 173 if (dev->flags & DM_FLAG_ACTIVATED) 174 return -EINVAL; 175 176 drv = dev->driver; 177 assert(drv); 178 179 if (drv->unbind) { 180 ret = drv->unbind(dev); 181 if (ret) 182 return ret; 183 } 184 185 ret = device_chld_unbind(dev); 186 if (ret) 187 return ret; 188 189 ret = uclass_unbind_device(dev); 190 if (ret) 191 return ret; 192 193 if (dev->parent) 194 list_del(&dev->sibling_node); 195 free(dev); 196 197 return 0; 198 } 199 200 /** 201 * device_free() - Free memory buffers allocated by a device 202 * @dev: Device that is to be started 203 */ 204 static void device_free(struct udevice *dev) 205 { 206 int size; 207 208 if (dev->driver->priv_auto_alloc_size) { 209 free(dev->priv); 210 dev->priv = NULL; 211 } 212 if (dev->flags & DM_FLAG_ALLOC_PDATA) { 213 free(dev->platdata); 214 dev->platdata = NULL; 215 } 216 size = dev->uclass->uc_drv->per_device_auto_alloc_size; 217 if (size) { 218 free(dev->uclass_priv); 219 dev->uclass_priv = NULL; 220 } 221 if (dev->parent) { 222 size = dev->parent->driver->per_child_auto_alloc_size; 223 if (size) { 224 free(dev->parent_priv); 225 dev->parent_priv = NULL; 226 } 227 } 228 } 229 230 int device_probe(struct udevice *dev) 231 { 232 struct driver *drv; 233 int size = 0; 234 int ret; 235 int seq; 236 237 if (!dev) 238 return -EINVAL; 239 240 if (dev->flags & DM_FLAG_ACTIVATED) 241 return 0; 242 243 drv = dev->driver; 244 assert(drv); 245 246 /* Allocate private data and platdata if requested */ 247 if (drv->priv_auto_alloc_size) { 248 dev->priv = calloc(1, drv->priv_auto_alloc_size); 249 if (!dev->priv) { 250 ret = -ENOMEM; 251 goto fail; 252 } 253 } 254 /* Allocate private data if requested */ 255 if (dev->flags & DM_FLAG_ALLOC_PDATA) { 256 dev->platdata = calloc(1, drv->platdata_auto_alloc_size); 257 if (!dev->platdata) { 258 ret = -ENOMEM; 259 goto fail; 260 } 261 } 262 size = dev->uclass->uc_drv->per_device_auto_alloc_size; 263 if (size) { 264 dev->uclass_priv = calloc(1, size); 265 if (!dev->uclass_priv) { 266 ret = -ENOMEM; 267 goto fail; 268 } 269 } 270 271 /* Ensure all parents are probed */ 272 if (dev->parent) { 273 size = dev->parent->driver->per_child_auto_alloc_size; 274 if (size) { 275 dev->parent_priv = calloc(1, size); 276 if (!dev->parent_priv) { 277 ret = -ENOMEM; 278 goto fail; 279 } 280 } 281 282 ret = device_probe(dev->parent); 283 if (ret) 284 goto fail; 285 } 286 287 seq = uclass_resolve_seq(dev); 288 if (seq < 0) { 289 ret = seq; 290 goto fail; 291 } 292 dev->seq = seq; 293 294 if (dev->parent && dev->parent->driver->child_pre_probe) { 295 ret = dev->parent->driver->child_pre_probe(dev); 296 if (ret) 297 goto fail; 298 } 299 300 if (drv->ofdata_to_platdata && dev->of_offset >= 0) { 301 ret = drv->ofdata_to_platdata(dev); 302 if (ret) 303 goto fail; 304 } 305 306 if (drv->probe) { 307 ret = drv->probe(dev); 308 if (ret) 309 goto fail; 310 } 311 312 dev->flags |= DM_FLAG_ACTIVATED; 313 314 ret = uclass_post_probe_device(dev); 315 if (ret) { 316 dev->flags &= ~DM_FLAG_ACTIVATED; 317 goto fail_uclass; 318 } 319 320 return 0; 321 fail_uclass: 322 if (device_remove(dev)) { 323 dm_warn("%s: Device '%s' failed to remove on error path\n", 324 __func__, dev->name); 325 } 326 fail: 327 dev->seq = -1; 328 device_free(dev); 329 330 return ret; 331 } 332 333 int device_remove(struct udevice *dev) 334 { 335 struct driver *drv; 336 int ret; 337 338 if (!dev) 339 return -EINVAL; 340 341 if (!(dev->flags & DM_FLAG_ACTIVATED)) 342 return 0; 343 344 drv = dev->driver; 345 assert(drv); 346 347 ret = uclass_pre_remove_device(dev); 348 if (ret) 349 return ret; 350 351 ret = device_chld_remove(dev); 352 if (ret) 353 goto err; 354 355 if (drv->remove) { 356 ret = drv->remove(dev); 357 if (ret) 358 goto err_remove; 359 } 360 361 if (dev->parent && dev->parent->driver->child_post_remove) { 362 ret = dev->parent->driver->child_post_remove(dev); 363 if (ret) { 364 dm_warn("%s: Device '%s' failed child_post_remove()", 365 __func__, dev->name); 366 } 367 } 368 369 device_free(dev); 370 371 dev->seq = -1; 372 dev->flags &= ~DM_FLAG_ACTIVATED; 373 374 return ret; 375 376 err_remove: 377 /* We can't put the children back */ 378 dm_warn("%s: Device '%s' failed to remove, but children are gone\n", 379 __func__, dev->name); 380 err: 381 ret = uclass_post_probe_device(dev); 382 if (ret) { 383 dm_warn("%s: Device '%s' failed to post_probe on error path\n", 384 __func__, dev->name); 385 } 386 387 return ret; 388 } 389 390 void *dev_get_platdata(struct udevice *dev) 391 { 392 if (!dev) { 393 dm_warn("%s: null device", __func__); 394 return NULL; 395 } 396 397 return dev->platdata; 398 } 399 400 void *dev_get_priv(struct udevice *dev) 401 { 402 if (!dev) { 403 dm_warn("%s: null device", __func__); 404 return NULL; 405 } 406 407 return dev->priv; 408 } 409 410 void *dev_get_parentdata(struct udevice *dev) 411 { 412 if (!dev) { 413 dm_warn("%s: null device", __func__); 414 return NULL; 415 } 416 417 return dev->parent_priv; 418 } 419 420 static int device_get_device_tail(struct udevice *dev, int ret, 421 struct udevice **devp) 422 { 423 if (ret) 424 return ret; 425 426 ret = device_probe(dev); 427 if (ret) 428 return ret; 429 430 *devp = dev; 431 432 return 0; 433 } 434 435 int device_get_child(struct udevice *parent, int index, struct udevice **devp) 436 { 437 struct udevice *dev; 438 439 list_for_each_entry(dev, &parent->child_head, sibling_node) { 440 if (!index--) 441 return device_get_device_tail(dev, 0, devp); 442 } 443 444 return -ENODEV; 445 } 446 447 int device_find_child_by_seq(struct udevice *parent, int seq_or_req_seq, 448 bool find_req_seq, struct udevice **devp) 449 { 450 struct udevice *dev; 451 452 *devp = NULL; 453 if (seq_or_req_seq == -1) 454 return -ENODEV; 455 456 list_for_each_entry(dev, &parent->child_head, sibling_node) { 457 if ((find_req_seq ? dev->req_seq : dev->seq) == 458 seq_or_req_seq) { 459 *devp = dev; 460 return 0; 461 } 462 } 463 464 return -ENODEV; 465 } 466 467 int device_get_child_by_seq(struct udevice *parent, int seq, 468 struct udevice **devp) 469 { 470 struct udevice *dev; 471 int ret; 472 473 *devp = NULL; 474 ret = device_find_child_by_seq(parent, seq, false, &dev); 475 if (ret == -ENODEV) { 476 /* 477 * We didn't find it in probed devices. See if there is one 478 * that will request this seq if probed. 479 */ 480 ret = device_find_child_by_seq(parent, seq, true, &dev); 481 } 482 return device_get_device_tail(dev, ret, devp); 483 } 484 485 int device_find_child_by_of_offset(struct udevice *parent, int of_offset, 486 struct udevice **devp) 487 { 488 struct udevice *dev; 489 490 *devp = NULL; 491 492 list_for_each_entry(dev, &parent->child_head, sibling_node) { 493 if (dev->of_offset == of_offset) { 494 *devp = dev; 495 return 0; 496 } 497 } 498 499 return -ENODEV; 500 } 501 502 int device_get_child_by_of_offset(struct udevice *parent, int seq, 503 struct udevice **devp) 504 { 505 struct udevice *dev; 506 int ret; 507 508 *devp = NULL; 509 ret = device_find_child_by_of_offset(parent, seq, &dev); 510 return device_get_device_tail(dev, ret, devp); 511 } 512