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 <malloc.h> 14 #include <dm/device.h> 15 #include <dm/device-internal.h> 16 #include <dm/lists.h> 17 #include <dm/platdata.h> 18 #include <dm/uclass.h> 19 #include <dm/uclass-internal.h> 20 #include <dm/util.h> 21 #include <linux/err.h> 22 #include <linux/list.h> 23 24 /** 25 * device_chld_unbind() - Unbind all device's children from the device 26 * 27 * On error, the function continues to unbind all children, and reports the 28 * first error. 29 * 30 * @dev: The device that is to be stripped of its children 31 * @return 0 on success, -ve on error 32 */ 33 static int device_chld_unbind(struct device *dev) 34 { 35 struct device *pos, *n; 36 int ret, saved_ret = 0; 37 38 assert(dev); 39 40 list_for_each_entry_safe(pos, n, &dev->child_head, sibling_node) { 41 ret = device_unbind(pos); 42 if (ret && !saved_ret) 43 saved_ret = ret; 44 } 45 46 return saved_ret; 47 } 48 49 /** 50 * device_chld_remove() - Stop all device's children 51 * @dev: The device whose children are to be removed 52 * @return 0 on success, -ve on error 53 */ 54 static int device_chld_remove(struct device *dev) 55 { 56 struct device *pos, *n; 57 int ret; 58 59 assert(dev); 60 61 list_for_each_entry_safe(pos, n, &dev->child_head, sibling_node) { 62 ret = device_remove(pos); 63 if (ret) 64 return ret; 65 } 66 67 return 0; 68 } 69 70 int device_bind(struct device *parent, struct driver *drv, const char *name, 71 void *platdata, int of_offset, struct device **devp) 72 { 73 struct device *dev; 74 struct uclass *uc; 75 int ret = 0; 76 77 *devp = NULL; 78 if (!name) 79 return -EINVAL; 80 81 ret = uclass_get(drv->id, &uc); 82 if (ret) 83 return ret; 84 85 dev = calloc(1, sizeof(struct device)); 86 if (!dev) 87 return -ENOMEM; 88 89 INIT_LIST_HEAD(&dev->sibling_node); 90 INIT_LIST_HEAD(&dev->child_head); 91 INIT_LIST_HEAD(&dev->uclass_node); 92 dev->platdata = platdata; 93 dev->name = name; 94 dev->of_offset = of_offset; 95 dev->parent = parent; 96 dev->driver = drv; 97 dev->uclass = uc; 98 if (!dev->platdata && drv->platdata_auto_alloc_size) 99 dev->flags |= DM_FLAG_ALLOC_PDATA; 100 101 /* put dev into parent's successor list */ 102 if (parent) 103 list_add_tail(&dev->sibling_node, &parent->child_head); 104 105 ret = uclass_bind_device(dev); 106 if (ret) 107 goto fail_bind; 108 109 /* if we fail to bind we remove device from successors and free it */ 110 if (drv->bind) { 111 ret = drv->bind(dev); 112 if (ret) { 113 if (uclass_unbind_device(dev)) { 114 dm_warn("Failed to unbind dev '%s' on error path\n", 115 dev->name); 116 } 117 goto fail_bind; 118 } 119 } 120 if (parent) 121 dm_dbg("Bound device %s to %s\n", dev->name, parent->name); 122 *devp = dev; 123 124 return 0; 125 126 fail_bind: 127 list_del(&dev->sibling_node); 128 free(dev); 129 return ret; 130 } 131 132 int device_bind_by_name(struct device *parent, const struct driver_info *info, 133 struct device **devp) 134 { 135 struct driver *drv; 136 137 drv = lists_driver_lookup_name(info->name); 138 if (!drv) 139 return -ENOENT; 140 141 return device_bind(parent, drv, info->name, (void *)info->platdata, 142 -1, devp); 143 } 144 145 int device_unbind(struct device *dev) 146 { 147 struct driver *drv; 148 int ret; 149 150 if (!dev) 151 return -EINVAL; 152 153 if (dev->flags & DM_FLAG_ACTIVATED) 154 return -EINVAL; 155 156 drv = dev->driver; 157 assert(drv); 158 159 if (drv->unbind) { 160 ret = drv->unbind(dev); 161 if (ret) 162 return ret; 163 } 164 165 ret = device_chld_unbind(dev); 166 if (ret) 167 return ret; 168 169 ret = uclass_unbind_device(dev); 170 if (ret) 171 return ret; 172 173 if (dev->parent) 174 list_del(&dev->sibling_node); 175 free(dev); 176 177 return 0; 178 } 179 180 /** 181 * device_free() - Free memory buffers allocated by a device 182 * @dev: Device that is to be started 183 */ 184 static void device_free(struct device *dev) 185 { 186 int size; 187 188 if (dev->driver->priv_auto_alloc_size) { 189 free(dev->priv); 190 dev->priv = NULL; 191 } 192 if (dev->flags & DM_FLAG_ALLOC_PDATA) { 193 free(dev->platdata); 194 dev->platdata = NULL; 195 } 196 size = dev->uclass->uc_drv->per_device_auto_alloc_size; 197 if (size) { 198 free(dev->uclass_priv); 199 dev->uclass_priv = NULL; 200 } 201 } 202 203 int device_probe(struct device *dev) 204 { 205 struct driver *drv; 206 int size = 0; 207 int ret; 208 209 if (!dev) 210 return -EINVAL; 211 212 if (dev->flags & DM_FLAG_ACTIVATED) 213 return 0; 214 215 drv = dev->driver; 216 assert(drv); 217 218 /* Allocate private data and platdata if requested */ 219 if (drv->priv_auto_alloc_size) { 220 dev->priv = calloc(1, drv->priv_auto_alloc_size); 221 if (!dev->priv) { 222 ret = -ENOMEM; 223 goto fail; 224 } 225 } 226 /* Allocate private data if requested */ 227 if (dev->flags & DM_FLAG_ALLOC_PDATA) { 228 dev->platdata = calloc(1, drv->platdata_auto_alloc_size); 229 if (!dev->platdata) { 230 ret = -ENOMEM; 231 goto fail; 232 } 233 } 234 size = dev->uclass->uc_drv->per_device_auto_alloc_size; 235 if (size) { 236 dev->uclass_priv = calloc(1, size); 237 if (!dev->uclass_priv) { 238 ret = -ENOMEM; 239 goto fail; 240 } 241 } 242 243 /* Ensure all parents are probed */ 244 if (dev->parent) { 245 ret = device_probe(dev->parent); 246 if (ret) 247 goto fail; 248 } 249 250 if (drv->ofdata_to_platdata && dev->of_offset >= 0) { 251 ret = drv->ofdata_to_platdata(dev); 252 if (ret) 253 goto fail; 254 } 255 256 if (drv->probe) { 257 ret = drv->probe(dev); 258 if (ret) 259 goto fail; 260 } 261 262 dev->flags |= DM_FLAG_ACTIVATED; 263 264 ret = uclass_post_probe_device(dev); 265 if (ret) { 266 dev->flags &= ~DM_FLAG_ACTIVATED; 267 goto fail_uclass; 268 } 269 270 return 0; 271 fail_uclass: 272 if (device_remove(dev)) { 273 dm_warn("%s: Device '%s' failed to remove on error path\n", 274 __func__, dev->name); 275 } 276 fail: 277 device_free(dev); 278 279 return ret; 280 } 281 282 int device_remove(struct device *dev) 283 { 284 struct driver *drv; 285 int ret; 286 287 if (!dev) 288 return -EINVAL; 289 290 if (!(dev->flags & DM_FLAG_ACTIVATED)) 291 return 0; 292 293 drv = dev->driver; 294 assert(drv); 295 296 ret = uclass_pre_remove_device(dev); 297 if (ret) 298 return ret; 299 300 ret = device_chld_remove(dev); 301 if (ret) 302 goto err; 303 304 if (drv->remove) { 305 ret = drv->remove(dev); 306 if (ret) 307 goto err_remove; 308 } 309 310 device_free(dev); 311 312 dev->flags &= ~DM_FLAG_ACTIVATED; 313 314 return 0; 315 316 err_remove: 317 /* We can't put the children back */ 318 dm_warn("%s: Device '%s' failed to remove, but children are gone\n", 319 __func__, dev->name); 320 err: 321 ret = uclass_post_probe_device(dev); 322 if (ret) { 323 dm_warn("%s: Device '%s' failed to post_probe on error path\n", 324 __func__, dev->name); 325 } 326 327 return ret; 328 } 329 330 void *dev_get_platdata(struct device *dev) 331 { 332 if (!dev) { 333 dm_warn("%s: null device", __func__); 334 return NULL; 335 } 336 337 return dev->platdata; 338 } 339 340 void *dev_get_priv(struct device *dev) 341 { 342 if (!dev) { 343 dm_warn("%s: null device", __func__); 344 return NULL; 345 } 346 347 return dev->priv; 348 } 349