drivers/acpi/glue.c

   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
  35 int register_acpi_bus_type(struct acpi_bus_type *type)
  36 {
  37         if (acpi_disabled)
  38                 return -ENODEV;
  39         if (type && type->bus && type->find_device) {
  40                 down_write(&bus_type_sem);
  41                 list_add_tail(&type->list, &bus_type_list);
  42                 up_write(&bus_type_sem);
  43                 printk(KERN_INFO PREFIX "bus type %s registered\n",
  44                        type->bus->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 "ACPI bus type %s unregistered\n",
  60                        type->bus->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 bus_type *type)
  68 {
  69         struct acpi_bus_type *tmp, *ret = NULL;
  70
  71         if (!type)
  72                 return NULL;
  73
  74         down_read(&bus_type_sem);
  75         list_for_each_entry(tmp, &bus_type_list, list) {
  76                 if (tmp->bus == type) {
  77                         ret = tmp;
  78                         break;
  79                 }
  80         }
  81         up_read(&bus_type_sem);
  82         return ret;
  83 }
  84
  85 static int acpi_find_bridge_device(struct device *dev, acpi_handle * handle)
  86 {
  87         struct acpi_bus_type *tmp;
  88         int ret = -ENODEV;
  89
  90         down_read(&bus_type_sem);
  91         list_for_each_entry(tmp, &bus_type_list, list) {
  92                 if (tmp->find_bridge && !tmp->find_bridge(dev, handle)) {
  93                         ret = 0;
  94                         break;
  95                 }
  96         }
  97         up_read(&bus_type_sem);
  98         return ret;
  99 }
 100
 101 /* Get device's handler per its address under its parent */
 102 struct acpi_find_child {
 103         acpi_handle handle;
 104         u64 address;
 105 };
 106
 107 static acpi_status
 108 do_acpi_find_child(acpi_handle handle, u32 lvl, void *context, void **rv)
 109 {
 110         acpi_status status;
 111         struct acpi_device_info *info;
 112         struct acpi_find_child *find = context;
 113
 114         status = acpi_get_object_info(handle, &info);
 115         if (ACPI_SUCCESS(status)) {
 116                 if ((info->address == find->address)
 117                         && (info->valid & ACPI_VALID_ADR))
 118                         find->handle = handle;
 119                 kfree(info);
 120         }
 121         return AE_OK;
 122 }
 123
 124 acpi_handle acpi_get_child(acpi_handle parent, u64 address)
 125 {
 126         struct acpi_find_child find = { NULL, address };
 127
 128         if (!parent)
 129                 return NULL;
 130         acpi_walk_namespace(ACPI_TYPE_DEVICE, parent,
 131                             1, do_acpi_find_child, NULL, &find, NULL);
 132         return find.handle;
 133 }
 134
 135 EXPORT_SYMBOL(acpi_get_child);
 136
 137 static int acpi_bind_one(struct device *dev, acpi_handle handle)
 138 {
 139         struct acpi_device *acpi_dev;
 140         acpi_status status;
 141         struct acpi_device_physical_node *physical_node, *pn;
 142         char physical_node_name[sizeof(PHYSICAL_NODE_STRING) + 2];
 143         int retval = -EINVAL;
 144
 145         if (ACPI_HANDLE(dev)) {
 146                 if (handle) {
 147                         dev_warn(dev, "ACPI handle is already set\n");
 148                         return -EINVAL;
 149                 } else {
 150                         handle = ACPI_HANDLE(dev);
 151                 }
 152         }
 153         if (!handle)
 154                 return -EINVAL;
 155
 156         get_device(dev);
 157         status = acpi_bus_get_device(handle, &acpi_dev);
 158         if (ACPI_FAILURE(status))
 159                 goto err;
 160
 161         physical_node = kzalloc(sizeof(*physical_node), GFP_KERNEL);
 162         if (!physical_node) {
 163                 retval = -ENOMEM;
 164                 goto err;
 165         }
 166
 167         mutex_lock(&acpi_dev->physical_node_lock);
 168
 169         /* Sanity check. */
 170         list_for_each_entry(pn, &acpi_dev->physical_node_list, node)
 171                 if (pn->dev == dev) {
 172                         dev_warn(dev, "Already associated with ACPI node\n");
 173                         goto err_free;
 174                 }
 175
 176         /* allocate physical node id according to physical_node_id_bitmap */
 177         physical_node->node_id =
 178                 find_first_zero_bit(acpi_dev->physical_node_id_bitmap,
 179                 ACPI_MAX_PHYSICAL_NODE);
 180         if (physical_node->node_id >= ACPI_MAX_PHYSICAL_NODE) {
 181                 retval = -ENOSPC;
 182                 goto err_free;
 183         }
 184
 185         set_bit(physical_node->node_id, acpi_dev->physical_node_id_bitmap);
 186         physical_node->dev = dev;
 187         list_add_tail(&physical_node->node, &acpi_dev->physical_node_list);
 188         acpi_dev->physical_node_count++;
 189
 190         mutex_unlock(&acpi_dev->physical_node_lock);
 191
 192         if (!ACPI_HANDLE(dev))
 193                 ACPI_HANDLE_SET(dev, acpi_dev->handle);
 194
 195         if (!physical_node->node_id)
 196                 strcpy(physical_node_name, PHYSICAL_NODE_STRING);
 197         else
 198                 sprintf(physical_node_name,
 199                         "physical_node%d", physical_node->node_id);
 200         retval = sysfs_create_link(&acpi_dev->dev.kobj, &dev->kobj,
 201                         physical_node_name);
 202         retval = sysfs_create_link(&dev->kobj, &acpi_dev->dev.kobj,
 203                 "firmware_node");
 204
 205         if (acpi_dev->wakeup.flags.valid)
 206                 device_set_wakeup_capable(dev, true);
 207
 208         return 0;
 209
 210  err:
 211         ACPI_HANDLE_SET(dev, NULL);
 212         put_device(dev);
 213         return retval;
 214
 215  err_free:
 216         mutex_unlock(&acpi_dev->physical_node_lock);
 217         kfree(physical_node);
 218         goto err;
 219 }
 220
 221 static int acpi_unbind_one(struct device *dev)
 222 {
 223         struct acpi_device_physical_node *entry;
 224         struct acpi_device *acpi_dev;
 225         acpi_status status;
 226         struct list_head *node, *next;
 227
 228         if (!ACPI_HANDLE(dev))
 229                 return 0;
 230
 231         status = acpi_bus_get_device(ACPI_HANDLE(dev), &acpi_dev);
 232         if (ACPI_FAILURE(status))
 233                 goto err;
 234
 235         mutex_lock(&acpi_dev->physical_node_lock);
 236         list_for_each_safe(node, next, &acpi_dev->physical_node_list) {
 237                 char physical_node_name[sizeof(PHYSICAL_NODE_STRING) + 2];
 238
 239                 entry = list_entry(node, struct acpi_device_physical_node,
 240                         node);
 241                 if (entry->dev != dev)
 242                         continue;
 243
 244                 list_del(node);
 245                 clear_bit(entry->node_id, acpi_dev->physical_node_id_bitmap);
 246
 247                 acpi_dev->physical_node_count--;
 248
 249                 if (!entry->node_id)
 250                         strcpy(physical_node_name, PHYSICAL_NODE_STRING);
 251                 else
 252                         sprintf(physical_node_name,
 253                                 "physical_node%d", entry->node_id);
 254
 255                 sysfs_remove_link(&acpi_dev->dev.kobj, physical_node_name);
 256                 sysfs_remove_link(&dev->kobj, "firmware_node");
 257                 ACPI_HANDLE_SET(dev, NULL);
 258                 /* acpi_bind_one increase refcnt by one */
 259                 put_device(dev);
 260                 kfree(entry);
 261         }
 262         mutex_unlock(&acpi_dev->physical_node_lock);
 263
 264         return 0;
 265
 266 err:
 267         dev_err(dev, "Oops, 'acpi_handle' corrupt\n");
 268         return -EINVAL;
 269 }
 270
 271 static int acpi_platform_notify(struct device *dev)
 272 {
 273         struct acpi_bus_type *type;
 274         acpi_handle handle;
 275         int ret;
 276
 277         ret = acpi_bind_one(dev, NULL);
 278         if (ret && (!dev->bus || !dev->parent)) {
 279                 /* bridge devices genernally haven't bus or parent */
 280                 ret = acpi_find_bridge_device(dev, &handle);
 281                 if (!ret) {
 282                         ret = acpi_bind_one(dev, handle);
 283                         if (ret)
 284                                 goto out;
 285                 }
 286         }
 287
 288         type = acpi_get_bus_type(dev->bus);
 289         if (ret) {
 290                 if (!type || !type->find_device) {
 291                         DBG("No ACPI bus support for %s\n", dev_name(dev));
 292                         ret = -EINVAL;
 293                         goto out;
 294                 }
 295
 296                 ret = type->find_device(dev, &handle);
 297                 if (ret) {
 298                         DBG("Unable to get handle for %s\n", dev_name(dev));
 299                         goto out;
 300                 }
 301                 ret = acpi_bind_one(dev, handle);
 302                 if (ret)
 303                         goto out;
 304         }
 305
 306         if (type && type->setup)
 307                 type->setup(dev);
 308
 309  out:
 310 #if ACPI_GLUE_DEBUG
 311         if (!ret) {
 312                 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 313
 314                 acpi_get_name(ACPI_HANDLE(dev), ACPI_FULL_PATHNAME, &buffer);
 315                 DBG("Device %s -> %s\n", dev_name(dev), (char *)buffer.pointer);
 316                 kfree(buffer.pointer);
 317         } else
 318                 DBG("Device %s -> No ACPI support\n", dev_name(dev));
 319 #endif
 320
 321         return ret;
 322 }
 323
 324 static int acpi_platform_notify_remove(struct device *dev)
 325 {
 326         struct acpi_bus_type *type;
 327
 328         type = acpi_get_bus_type(dev->bus);
 329         if (type && type->cleanup)
 330                 type->cleanup(dev);
 331
 332         acpi_unbind_one(dev);
 333         return 0;
 334 }
 335
 336 int __init init_acpi_device_notify(void)
 337 {
 338         if (platform_notify || platform_notify_remove) {
 339                 printk(KERN_ERR PREFIX "Can't use platform_notify\n");
 340                 return 0;
 341         }
 342         platform_notify = acpi_platform_notify;
 343         platform_notify_remove = acpi_platform_notify_remove;
 344         return 0;
 345 }