| 1 | /* |
| 2 | * Link physical devices with ACPI devices support |
| 3 | * |
| 4 | * Copyright (c) 2005 David Shaohua Li <shaohua.li@intel.com> |
| 5 | * Copyright (c) 2005 Intel Corp. |
| 6 | * |
| 7 | * This file is released under the GPLv2. |
| 8 | */ |
| 9 | #include <linux/export.h> |
| 10 | #include <linux/init.h> |
| 11 | #include <linux/list.h> |
| 12 | #include <linux/device.h> |
| 13 | #include <linux/slab.h> |
| 14 | #include <linux/rwsem.h> |
| 15 | #include <linux/acpi.h> |
| 16 | |
| 17 | #include "internal.h" |
| 18 | |
| 19 | #define ACPI_GLUE_DEBUG 0 |
| 20 | #if ACPI_GLUE_DEBUG |
| 21 | #define DBG(fmt, ...) \ |
| 22 | printk(KERN_DEBUG PREFIX fmt, ##__VA_ARGS__) |
| 23 | #else |
| 24 | #define DBG(fmt, ...) \ |
| 25 | do { \ |
| 26 | if (0) \ |
| 27 | printk(KERN_DEBUG PREFIX fmt, ##__VA_ARGS__); \ |
| 28 | } while (0) |
| 29 | #endif |
| 30 | static LIST_HEAD(bus_type_list); |
| 31 | static DECLARE_RWSEM(bus_type_sem); |
| 32 | |
| 33 | #define PHYSICAL_NODE_STRING "physical_node" |
| 34 | #define PHYSICAL_NODE_NAME_SIZE (sizeof(PHYSICAL_NODE_STRING) + 10) |
| 35 | |
| 36 | int register_acpi_bus_type(struct acpi_bus_type *type) |
| 37 | { |
| 38 | if (acpi_disabled) |
| 39 | return -ENODEV; |
| 40 | if (type && type->match && type->find_device) { |
| 41 | down_write(&bus_type_sem); |
| 42 | list_add_tail(&type->list, &bus_type_list); |
| 43 | up_write(&bus_type_sem); |
| 44 | printk(KERN_INFO PREFIX "bus type %s registered\n", type->name); |
| 45 | return 0; |
| 46 | } |
| 47 | return -ENODEV; |
| 48 | } |
| 49 | EXPORT_SYMBOL_GPL(register_acpi_bus_type); |
| 50 | |
| 51 | int unregister_acpi_bus_type(struct acpi_bus_type *type) |
| 52 | { |
| 53 | if (acpi_disabled) |
| 54 | return 0; |
| 55 | if (type) { |
| 56 | down_write(&bus_type_sem); |
| 57 | list_del_init(&type->list); |
| 58 | up_write(&bus_type_sem); |
| 59 | printk(KERN_INFO PREFIX "bus type %s unregistered\n", |
| 60 | type->name); |
| 61 | return 0; |
| 62 | } |
| 63 | return -ENODEV; |
| 64 | } |
| 65 | EXPORT_SYMBOL_GPL(unregister_acpi_bus_type); |
| 66 | |
| 67 | static struct acpi_bus_type *acpi_get_bus_type(struct device *dev) |
| 68 | { |
| 69 | struct acpi_bus_type *tmp, *ret = NULL; |
| 70 | |
| 71 | down_read(&bus_type_sem); |
| 72 | list_for_each_entry(tmp, &bus_type_list, list) { |
| 73 | if (tmp->match(dev)) { |
| 74 | ret = tmp; |
| 75 | break; |
| 76 | } |
| 77 | } |
| 78 | up_read(&bus_type_sem); |
| 79 | return ret; |
| 80 | } |
| 81 | |
| 82 | #define FIND_CHILD_MIN_SCORE 1 |
| 83 | #define FIND_CHILD_MAX_SCORE 2 |
| 84 | |
| 85 | static acpi_status acpi_dev_present(acpi_handle handle, u32 lvl_not_used, |
| 86 | void *not_used, void **ret_p) |
| 87 | { |
| 88 | struct acpi_device *adev = NULL; |
| 89 | |
| 90 | acpi_bus_get_device(handle, &adev); |
| 91 | if (adev) { |
| 92 | *ret_p = handle; |
| 93 | return AE_CTRL_TERMINATE; |
| 94 | } |
| 95 | return AE_OK; |
| 96 | } |
| 97 | |
| 98 | static int do_find_child_checks(acpi_handle handle, bool is_bridge) |
| 99 | { |
| 100 | bool sta_present = true; |
| 101 | unsigned long long sta; |
| 102 | acpi_status status; |
| 103 | |
| 104 | status = acpi_evaluate_integer(handle, "_STA", NULL, &sta); |
| 105 | if (status == AE_NOT_FOUND) |
| 106 | sta_present = false; |
| 107 | else if (ACPI_FAILURE(status) || !(sta & ACPI_STA_DEVICE_ENABLED)) |
| 108 | return -ENODEV; |
| 109 | |
| 110 | if (is_bridge) { |
| 111 | void *test = NULL; |
| 112 | |
| 113 | /* Check if this object has at least one child device. */ |
| 114 | acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1, |
| 115 | acpi_dev_present, NULL, NULL, &test); |
| 116 | if (!test) |
| 117 | return -ENODEV; |
| 118 | } |
| 119 | return sta_present ? FIND_CHILD_MAX_SCORE : FIND_CHILD_MIN_SCORE; |
| 120 | } |
| 121 | |
| 122 | struct find_child_context { |
| 123 | u64 addr; |
| 124 | bool is_bridge; |
| 125 | acpi_handle ret; |
| 126 | int ret_score; |
| 127 | }; |
| 128 | |
| 129 | static acpi_status do_find_child(acpi_handle handle, u32 lvl_not_used, |
| 130 | void *data, void **not_used) |
| 131 | { |
| 132 | struct find_child_context *context = data; |
| 133 | unsigned long long addr; |
| 134 | acpi_status status; |
| 135 | int score; |
| 136 | |
| 137 | status = acpi_evaluate_integer(handle, METHOD_NAME__ADR, NULL, &addr); |
| 138 | if (ACPI_FAILURE(status) || addr != context->addr) |
| 139 | return AE_OK; |
| 140 | |
| 141 | if (!context->ret) { |
| 142 | /* This is the first matching object. Save its handle. */ |
| 143 | context->ret = handle; |
| 144 | return AE_OK; |
| 145 | } |
| 146 | /* |
| 147 | * There is more than one matching object with the same _ADR value. |
| 148 | * That really is unexpected, so we are kind of beyond the scope of the |
| 149 | * spec here. We have to choose which one to return, though. |
| 150 | * |
| 151 | * First, check if the previously found object is good enough and return |
| 152 | * its handle if so. Second, check the same for the object that we've |
| 153 | * just found. |
| 154 | */ |
| 155 | if (!context->ret_score) { |
| 156 | score = do_find_child_checks(context->ret, context->is_bridge); |
| 157 | if (score == FIND_CHILD_MAX_SCORE) |
| 158 | return AE_CTRL_TERMINATE; |
| 159 | else |
| 160 | context->ret_score = score; |
| 161 | } |
| 162 | score = do_find_child_checks(handle, context->is_bridge); |
| 163 | if (score == FIND_CHILD_MAX_SCORE) { |
| 164 | context->ret = handle; |
| 165 | return AE_CTRL_TERMINATE; |
| 166 | } else if (score > context->ret_score) { |
| 167 | context->ret = handle; |
| 168 | context->ret_score = score; |
| 169 | } |
| 170 | return AE_OK; |
| 171 | } |
| 172 | |
| 173 | acpi_handle acpi_find_child(acpi_handle parent, u64 addr, bool is_bridge) |
| 174 | { |
| 175 | if (parent) { |
| 176 | struct find_child_context context = { |
| 177 | .addr = addr, |
| 178 | .is_bridge = is_bridge, |
| 179 | }; |
| 180 | |
| 181 | acpi_walk_namespace(ACPI_TYPE_DEVICE, parent, 1, do_find_child, |
| 182 | NULL, &context, NULL); |
| 183 | return context.ret; |
| 184 | } |
| 185 | return NULL; |
| 186 | } |
| 187 | EXPORT_SYMBOL_GPL(acpi_find_child); |
| 188 | |
| 189 | static void acpi_physnode_link_name(char *buf, unsigned int node_id) |
| 190 | { |
| 191 | if (node_id > 0) |
| 192 | snprintf(buf, PHYSICAL_NODE_NAME_SIZE, |
| 193 | PHYSICAL_NODE_STRING "%u", node_id); |
| 194 | else |
| 195 | strcpy(buf, PHYSICAL_NODE_STRING); |
| 196 | } |
| 197 | |
| 198 | int acpi_bind_one(struct device *dev, acpi_handle handle) |
| 199 | { |
| 200 | struct acpi_device *acpi_dev; |
| 201 | acpi_status status; |
| 202 | struct acpi_device_physical_node *physical_node, *pn; |
| 203 | char physical_node_name[PHYSICAL_NODE_NAME_SIZE]; |
| 204 | struct list_head *physnode_list; |
| 205 | unsigned int node_id; |
| 206 | int retval = -EINVAL; |
| 207 | |
| 208 | if (ACPI_HANDLE(dev)) { |
| 209 | if (handle) { |
| 210 | dev_warn(dev, "ACPI handle is already set\n"); |
| 211 | return -EINVAL; |
| 212 | } else { |
| 213 | handle = ACPI_HANDLE(dev); |
| 214 | } |
| 215 | } |
| 216 | if (!handle) |
| 217 | return -EINVAL; |
| 218 | |
| 219 | get_device(dev); |
| 220 | status = acpi_bus_get_device(handle, &acpi_dev); |
| 221 | if (ACPI_FAILURE(status)) |
| 222 | goto err; |
| 223 | |
| 224 | physical_node = kzalloc(sizeof(*physical_node), GFP_KERNEL); |
| 225 | if (!physical_node) { |
| 226 | retval = -ENOMEM; |
| 227 | goto err; |
| 228 | } |
| 229 | |
| 230 | mutex_lock(&acpi_dev->physical_node_lock); |
| 231 | |
| 232 | /* |
| 233 | * Keep the list sorted by node_id so that the IDs of removed nodes can |
| 234 | * be recycled easily. |
| 235 | */ |
| 236 | physnode_list = &acpi_dev->physical_node_list; |
| 237 | node_id = 0; |
| 238 | list_for_each_entry(pn, &acpi_dev->physical_node_list, node) { |
| 239 | /* Sanity check. */ |
| 240 | if (pn->dev == dev) { |
| 241 | mutex_unlock(&acpi_dev->physical_node_lock); |
| 242 | |
| 243 | dev_warn(dev, "Already associated with ACPI node\n"); |
| 244 | kfree(physical_node); |
| 245 | if (ACPI_HANDLE(dev) != handle) |
| 246 | goto err; |
| 247 | |
| 248 | put_device(dev); |
| 249 | return 0; |
| 250 | } |
| 251 | if (pn->node_id == node_id) { |
| 252 | physnode_list = &pn->node; |
| 253 | node_id++; |
| 254 | } |
| 255 | } |
| 256 | |
| 257 | physical_node->node_id = node_id; |
| 258 | physical_node->dev = dev; |
| 259 | list_add(&physical_node->node, physnode_list); |
| 260 | acpi_dev->physical_node_count++; |
| 261 | |
| 262 | if (!ACPI_HANDLE(dev)) |
| 263 | ACPI_HANDLE_SET(dev, acpi_dev->handle); |
| 264 | |
| 265 | acpi_physnode_link_name(physical_node_name, node_id); |
| 266 | retval = sysfs_create_link(&acpi_dev->dev.kobj, &dev->kobj, |
| 267 | physical_node_name); |
| 268 | if (retval) |
| 269 | dev_err(&acpi_dev->dev, "Failed to create link %s (%d)\n", |
| 270 | physical_node_name, retval); |
| 271 | |
| 272 | retval = sysfs_create_link(&dev->kobj, &acpi_dev->dev.kobj, |
| 273 | "firmware_node"); |
| 274 | if (retval) |
| 275 | dev_err(dev, "Failed to create link firmware_node (%d)\n", |
| 276 | retval); |
| 277 | |
| 278 | mutex_unlock(&acpi_dev->physical_node_lock); |
| 279 | |
| 280 | if (acpi_dev->wakeup.flags.valid) |
| 281 | device_set_wakeup_capable(dev, true); |
| 282 | |
| 283 | return 0; |
| 284 | |
| 285 | err: |
| 286 | ACPI_HANDLE_SET(dev, NULL); |
| 287 | put_device(dev); |
| 288 | return retval; |
| 289 | } |
| 290 | EXPORT_SYMBOL_GPL(acpi_bind_one); |
| 291 | |
| 292 | int acpi_unbind_one(struct device *dev) |
| 293 | { |
| 294 | struct acpi_device_physical_node *entry; |
| 295 | struct acpi_device *acpi_dev; |
| 296 | acpi_status status; |
| 297 | |
| 298 | if (!ACPI_HANDLE(dev)) |
| 299 | return 0; |
| 300 | |
| 301 | status = acpi_bus_get_device(ACPI_HANDLE(dev), &acpi_dev); |
| 302 | if (ACPI_FAILURE(status)) { |
| 303 | dev_err(dev, "Oops, ACPI handle corrupt in %s()\n", __func__); |
| 304 | return -EINVAL; |
| 305 | } |
| 306 | |
| 307 | mutex_lock(&acpi_dev->physical_node_lock); |
| 308 | |
| 309 | list_for_each_entry(entry, &acpi_dev->physical_node_list, node) |
| 310 | if (entry->dev == dev) { |
| 311 | char physnode_name[PHYSICAL_NODE_NAME_SIZE]; |
| 312 | |
| 313 | list_del(&entry->node); |
| 314 | acpi_dev->physical_node_count--; |
| 315 | |
| 316 | acpi_physnode_link_name(physnode_name, entry->node_id); |
| 317 | sysfs_remove_link(&acpi_dev->dev.kobj, physnode_name); |
| 318 | sysfs_remove_link(&dev->kobj, "firmware_node"); |
| 319 | ACPI_HANDLE_SET(dev, NULL); |
| 320 | /* acpi_bind_one() increase refcnt by one. */ |
| 321 | put_device(dev); |
| 322 | kfree(entry); |
| 323 | break; |
| 324 | } |
| 325 | |
| 326 | mutex_unlock(&acpi_dev->physical_node_lock); |
| 327 | return 0; |
| 328 | } |
| 329 | EXPORT_SYMBOL_GPL(acpi_unbind_one); |
| 330 | |
| 331 | static int acpi_platform_notify(struct device *dev) |
| 332 | { |
| 333 | struct acpi_bus_type *type = acpi_get_bus_type(dev); |
| 334 | acpi_handle handle; |
| 335 | int ret; |
| 336 | |
| 337 | ret = acpi_bind_one(dev, NULL); |
| 338 | if (ret && type) { |
| 339 | ret = type->find_device(dev, &handle); |
| 340 | if (ret) { |
| 341 | DBG("Unable to get handle for %s\n", dev_name(dev)); |
| 342 | goto out; |
| 343 | } |
| 344 | ret = acpi_bind_one(dev, handle); |
| 345 | if (ret) |
| 346 | goto out; |
| 347 | } |
| 348 | |
| 349 | if (type && type->setup) |
| 350 | type->setup(dev); |
| 351 | |
| 352 | out: |
| 353 | #if ACPI_GLUE_DEBUG |
| 354 | if (!ret) { |
| 355 | struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; |
| 356 | |
| 357 | acpi_get_name(ACPI_HANDLE(dev), ACPI_FULL_PATHNAME, &buffer); |
| 358 | DBG("Device %s -> %s\n", dev_name(dev), (char *)buffer.pointer); |
| 359 | kfree(buffer.pointer); |
| 360 | } else |
| 361 | DBG("Device %s -> No ACPI support\n", dev_name(dev)); |
| 362 | #endif |
| 363 | |
| 364 | return ret; |
| 365 | } |
| 366 | |
| 367 | static int acpi_platform_notify_remove(struct device *dev) |
| 368 | { |
| 369 | struct acpi_bus_type *type; |
| 370 | |
| 371 | type = acpi_get_bus_type(dev); |
| 372 | if (type && type->cleanup) |
| 373 | type->cleanup(dev); |
| 374 | |
| 375 | acpi_unbind_one(dev); |
| 376 | return 0; |
| 377 | } |
| 378 | |
| 379 | int __init init_acpi_device_notify(void) |
| 380 | { |
| 381 | if (platform_notify || platform_notify_remove) { |
| 382 | printk(KERN_ERR PREFIX "Can't use platform_notify\n"); |
| 383 | return 0; |
| 384 | } |
| 385 | platform_notify = acpi_platform_notify; |
| 386 | platform_notify_remove = acpi_platform_notify_remove; |
| 387 | return 0; |
| 388 | } |