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