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(struct udevice *dev) 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 } 286 287 ret = device_probe(dev->parent); 288 if (ret) 289 goto fail; 290 } 291 292 seq = uclass_resolve_seq(dev); 293 if (seq < 0) { 294 ret = seq; 295 goto fail; 296 } 297 dev->seq = seq; 298 299 if (dev->parent && dev->parent->driver->child_pre_probe) { 300 ret = dev->parent->driver->child_pre_probe(dev); 301 if (ret) 302 goto fail; 303 } 304 305 if (drv->ofdata_to_platdata && dev->of_offset >= 0) { 306 ret = drv->ofdata_to_platdata(dev); 307 if (ret) 308 goto fail; 309 } 310 311 if (drv->probe) { 312 ret = drv->probe(dev); 313 if (ret) 314 goto fail; 315 } 316 317 dev->flags |= DM_FLAG_ACTIVATED; 318 319 ret = uclass_post_probe_device(dev); 320 if (ret) { 321 dev->flags &= ~DM_FLAG_ACTIVATED; 322 goto fail_uclass; 323 } 324 325 return 0; 326 fail_uclass: 327 if (device_remove(dev)) { 328 dm_warn("%s: Device '%s' failed to remove on error path\n", 329 __func__, dev->name); 330 } 331 fail: 332 dev->seq = -1; 333 device_free(dev); 334 335 return ret; 336 } 337 338 int device_remove(struct udevice *dev) 339 { 340 struct driver *drv; 341 int ret; 342 343 if (!dev) 344 return -EINVAL; 345 346 if (!(dev->flags & DM_FLAG_ACTIVATED)) 347 return 0; 348 349 drv = dev->driver; 350 assert(drv); 351 352 ret = uclass_pre_remove_device(dev); 353 if (ret) 354 return ret; 355 356 ret = device_chld_remove(dev); 357 if (ret) 358 goto err; 359 360 if (drv->remove) { 361 ret = drv->remove(dev); 362 if (ret) 363 goto err_remove; 364 } 365 366 if (dev->parent && dev->parent->driver->child_post_remove) { 367 ret = dev->parent->driver->child_post_remove(dev); 368 if (ret) { 369 dm_warn("%s: Device '%s' failed child_post_remove()", 370 __func__, dev->name); 371 } 372 } 373 374 device_free(dev); 375 376 dev->seq = -1; 377 dev->flags &= ~DM_FLAG_ACTIVATED; 378 379 return ret; 380 381 err_remove: 382 /* We can't put the children back */ 383 dm_warn("%s: Device '%s' failed to remove, but children are gone\n", 384 __func__, dev->name); 385 err: 386 ret = uclass_post_probe_device(dev); 387 if (ret) { 388 dm_warn("%s: Device '%s' failed to post_probe on error path\n", 389 __func__, dev->name); 390 } 391 392 return ret; 393 } 394 395 void *dev_get_platdata(struct udevice *dev) 396 { 397 if (!dev) { 398 dm_warn("%s: null device", __func__); 399 return NULL; 400 } 401 402 return dev->platdata; 403 } 404 405 void *dev_get_priv(struct udevice *dev) 406 { 407 if (!dev) { 408 dm_warn("%s: null device", __func__); 409 return NULL; 410 } 411 412 return dev->priv; 413 } 414 415 void *dev_get_parentdata(struct udevice *dev) 416 { 417 if (!dev) { 418 dm_warn("%s: null device", __func__); 419 return NULL; 420 } 421 422 return dev->parent_priv; 423 } 424 425 static int device_get_device_tail(struct udevice *dev, int ret, 426 struct udevice **devp) 427 { 428 if (ret) 429 return ret; 430 431 ret = device_probe(dev); 432 if (ret) 433 return ret; 434 435 *devp = dev; 436 437 return 0; 438 } 439 440 int device_get_child(struct udevice *parent, int index, struct udevice **devp) 441 { 442 struct udevice *dev; 443 444 list_for_each_entry(dev, &parent->child_head, sibling_node) { 445 if (!index--) 446 return device_get_device_tail(dev, 0, devp); 447 } 448 449 return -ENODEV; 450 } 451 452 int device_find_child_by_seq(struct udevice *parent, int seq_or_req_seq, 453 bool find_req_seq, struct udevice **devp) 454 { 455 struct udevice *dev; 456 457 *devp = NULL; 458 if (seq_or_req_seq == -1) 459 return -ENODEV; 460 461 list_for_each_entry(dev, &parent->child_head, sibling_node) { 462 if ((find_req_seq ? dev->req_seq : dev->seq) == 463 seq_or_req_seq) { 464 *devp = dev; 465 return 0; 466 } 467 } 468 469 return -ENODEV; 470 } 471 472 int device_get_child_by_seq(struct udevice *parent, int seq, 473 struct udevice **devp) 474 { 475 struct udevice *dev; 476 int ret; 477 478 *devp = NULL; 479 ret = device_find_child_by_seq(parent, seq, false, &dev); 480 if (ret == -ENODEV) { 481 /* 482 * We didn't find it in probed devices. See if there is one 483 * that will request this seq if probed. 484 */ 485 ret = device_find_child_by_seq(parent, seq, true, &dev); 486 } 487 return device_get_device_tail(dev, ret, devp); 488 } 489 490 int device_find_child_by_of_offset(struct udevice *parent, int of_offset, 491 struct udevice **devp) 492 { 493 struct udevice *dev; 494 495 *devp = NULL; 496 497 list_for_each_entry(dev, &parent->child_head, sibling_node) { 498 if (dev->of_offset == of_offset) { 499 *devp = dev; 500 return 0; 501 } 502 } 503 504 return -ENODEV; 505 } 506 507 int device_get_child_by_of_offset(struct udevice *parent, int seq, 508 struct udevice **devp) 509 { 510 struct udevice *dev; 511 int ret; 512 513 *devp = NULL; 514 ret = device_find_child_by_of_offset(parent, seq, &dev); 515 return device_get_device_tail(dev, ret, devp); 516 } 517