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