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->match && 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", type->name);
  44                 return 0;
  45         }
  46         return -ENODEV;
  47 }
  48 EXPORT_SYMBOL_GPL(register_acpi_bus_type);
  49
  50 int unregister_acpi_bus_type(struct acpi_bus_type *type)
  51 {
  52         if (acpi_disabled)
  53                 return 0;
  54         if (type) {
  55                 down_write(&bus_type_sem);
  56                 list_del_init(&type->list);
  57                 up_write(&bus_type_sem);
  58                 printk(KERN_INFO PREFIX "bus type %s unregistered\n",
  59                        type->name);
  60                 return 0;
  61         }
  62         return -ENODEV;
  63 }
  64 EXPORT_SYMBOL_GPL(unregister_acpi_bus_type);
  65
  66 static struct acpi_bus_type *acpi_get_bus_type(struct device *dev)
  67 {
  68         struct acpi_bus_type *tmp, *ret = NULL;
  69
  70         down_read(&bus_type_sem);
  71         list_for_each_entry(tmp, &bus_type_list, list) {
  72                 if (tmp->match(dev)) {
  73                         ret = tmp;
  74                         break;
  75                 }
  76         }
  77         up_read(&bus_type_sem);
  78         return ret;
  79 }
  80
  81 static int acpi_find_bridge_device(struct device *dev, acpi_handle * handle)
  82 {
  83         struct acpi_bus_type *tmp;
  84         int ret = -ENODEV;
  85
  86         down_read(&bus_type_sem);
  87         list_for_each_entry(tmp, &bus_type_list, list) {
  88                 if (tmp->find_bridge && !tmp->find_bridge(dev, handle)) {
  89                         ret = 0;
  90                         break;
  91                 }
  92         }
  93         up_read(&bus_type_sem);
  94         return ret;
  95 }
  96
  97 static acpi_status do_acpi_find_child(acpi_handle handle, u32 lvl_not_used,
  98                                       void *addr_p, void **ret_p)
  99 {
 100         unsigned long long addr;
 101         acpi_status status;
 102
 103         status = acpi_evaluate_integer(handle, METHOD_NAME__ADR, NULL, &addr);
 104         if (ACPI_SUCCESS(status) && addr == *((u64 *)addr_p)) {
 105                 *ret_p = handle;
 106                 return AE_CTRL_TERMINATE;
 107         }
 108         return AE_OK;
 109 }
 110
 111 acpi_handle acpi_get_child(acpi_handle parent, u64 address)
 112 {
 113         void *ret = NULL;
 114
 115         if (!parent)
 116                 return NULL;
 117
 118         acpi_walk_namespace(ACPI_TYPE_DEVICE, parent, 1, NULL,
 119                             do_acpi_find_child, &address, &ret);
 120         return (acpi_handle)ret;
 121 }
 122 EXPORT_SYMBOL(acpi_get_child);
 123
 124 static int acpi_bind_one(struct device *dev, acpi_handle handle)
 125 {
 126         struct acpi_device *acpi_dev;
 127         acpi_status status;
 128         struct acpi_device_physical_node *physical_node, *pn;
 129         char physical_node_name[sizeof(PHYSICAL_NODE_STRING) + 2];
 130         int retval = -EINVAL;
 131
 132         if (ACPI_HANDLE(dev)) {
 133                 if (handle) {
 134                         dev_warn(dev, "ACPI handle is already set\n");
 135                         return -EINVAL;
 136                 } else {
 137                         handle = ACPI_HANDLE(dev);
 138                 }
 139         }
 140         if (!handle)
 141                 return -EINVAL;
 142
 143         get_device(dev);
 144         status = acpi_bus_get_device(handle, &acpi_dev);
 145         if (ACPI_FAILURE(status))
 146                 goto err;
 147
 148         physical_node = kzalloc(sizeof(*physical_node), GFP_KERNEL);
 149         if (!physical_node) {
 150                 retval = -ENOMEM;
 151                 goto err;
 152         }
 153
 154         mutex_lock(&acpi_dev->physical_node_lock);
 155
 156         /* Sanity check. */
 157         list_for_each_entry(pn, &acpi_dev->physical_node_list, node)
 158                 if (pn->dev == dev) {
 159                         dev_warn(dev, "Already associated with ACPI node\n");
 160                         goto err_free;
 161                 }
 162
 163         /* allocate physical node id according to physical_node_id_bitmap */
 164         physical_node->node_id =
 165                 find_first_zero_bit(acpi_dev->physical_node_id_bitmap,
 166                 ACPI_MAX_PHYSICAL_NODE);
 167         if (physical_node->node_id >= ACPI_MAX_PHYSICAL_NODE) {
 168                 retval = -ENOSPC;
 169                 goto err_free;
 170         }
 171
 172         set_bit(physical_node->node_id, acpi_dev->physical_node_id_bitmap);
 173         physical_node->dev = dev;
 174         list_add_tail(&physical_node->node, &acpi_dev->physical_node_list);
 175         acpi_dev->physical_node_count++;
 176
 177         mutex_unlock(&acpi_dev->physical_node_lock);
 178
 179         if (!ACPI_HANDLE(dev))
 180                 ACPI_HANDLE_SET(dev, acpi_dev->handle);
 181
 182         if (!physical_node->node_id)
 183                 strcpy(physical_node_name, PHYSICAL_NODE_STRING);
 184         else
 185                 sprintf(physical_node_name,
 186                         "physical_node%d", physical_node->node_id);
 187         retval = sysfs_create_link(&acpi_dev->dev.kobj, &dev->kobj,
 188                         physical_node_name);
 189         retval = sysfs_create_link(&dev->kobj, &acpi_dev->dev.kobj,
 190                 "firmware_node");
 191
 192         if (acpi_dev->wakeup.flags.valid)
 193                 device_set_wakeup_capable(dev, true);
 194
 195         return 0;
 196
 197  err:
 198         ACPI_HANDLE_SET(dev, NULL);
 199         put_device(dev);
 200         return retval;
 201
 202  err_free:
 203         mutex_unlock(&acpi_dev->physical_node_lock);
 204         kfree(physical_node);
 205         goto err;
 206 }
 207
 208 static int acpi_unbind_one(struct device *dev)
 209 {
 210         struct acpi_device_physical_node *entry;
 211         struct acpi_device *acpi_dev;
 212         acpi_status status;
 213         struct list_head *node, *next;
 214
 215         if (!ACPI_HANDLE(dev))
 216                 return 0;
 217
 218         status = acpi_bus_get_device(ACPI_HANDLE(dev), &acpi_dev);
 219         if (ACPI_FAILURE(status))
 220                 goto err;
 221
 222         mutex_lock(&acpi_dev->physical_node_lock);
 223         list_for_each_safe(node, next, &acpi_dev->physical_node_list) {
 224                 char physical_node_name[sizeof(PHYSICAL_NODE_STRING) + 2];
 225
 226                 entry = list_entry(node, struct acpi_device_physical_node,
 227                         node);
 228                 if (entry->dev != dev)
 229                         continue;
 230
 231                 list_del(node);
 232                 clear_bit(entry->node_id, acpi_dev->physical_node_id_bitmap);
 233
 234                 acpi_dev->physical_node_count--;
 235
 236                 if (!entry->node_id)
 237                         strcpy(physical_node_name, PHYSICAL_NODE_STRING);
 238                 else
 239                         sprintf(physical_node_name,
 240                                 "physical_node%d", entry->node_id);
 241
 242                 sysfs_remove_link(&acpi_dev->dev.kobj, physical_node_name);
 243                 sysfs_remove_link(&dev->kobj, "firmware_node");
 244                 ACPI_HANDLE_SET(dev, NULL);
 245                 /* acpi_bind_one increase refcnt by one */
 246                 put_device(dev);
 247                 kfree(entry);
 248         }
 249         mutex_unlock(&acpi_dev->physical_node_lock);
 250
 251         return 0;
 252
 253 err:
 254         dev_err(dev, "Oops, 'acpi_handle' corrupt\n");
 255         return -EINVAL;
 256 }
 257
 258 static int acpi_platform_notify(struct device *dev)
 259 {
 260         struct acpi_bus_type *type = acpi_get_bus_type(dev);
 261         acpi_handle handle;
 262         int ret;
 263
 264         ret = acpi_bind_one(dev, NULL);
 265         if (ret) {
 266                 if (!type) {
 267                         ret = acpi_find_bridge_device(dev, &handle);
 268                         if (!ret)
 269                                 ret = acpi_bind_one(dev, handle);
 270
 271                         goto out;
 272                 }
 273
 274                 ret = type->find_device(dev, &handle);
 275                 if (ret) {
 276                         DBG("Unable to get handle for %s\n", dev_name(dev));
 277                         goto out;
 278                 }
 279                 ret = acpi_bind_one(dev, handle);
 280                 if (ret)
 281                         goto out;
 282         }
 283
 284         if (type && type->setup)
 285                 type->setup(dev);
 286
 287  out:
 288 #if ACPI_GLUE_DEBUG
 289         if (!ret) {
 290                 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 291
 292                 acpi_get_name(ACPI_HANDLE(dev), ACPI_FULL_PATHNAME, &buffer);
 293                 DBG("Device %s -> %s\n", dev_name(dev), (char *)buffer.pointer);
 294                 kfree(buffer.pointer);
 295         } else
 296                 DBG("Device %s -> No ACPI support\n", dev_name(dev));
 297 #endif
 298
 299         return ret;
 300 }
 301
 302 static int acpi_platform_notify_remove(struct device *dev)
 303 {
 304         struct acpi_bus_type *type;
 305
 306         type = acpi_get_bus_type(dev);
 307         if (type && type->cleanup)
 308                 type->cleanup(dev);
 309
 310         acpi_unbind_one(dev);
 311         return 0;
 312 }
 313
 314 int __init init_acpi_device_notify(void)
 315 {
 316         if (platform_notify || platform_notify_remove) {
 317                 printk(KERN_ERR PREFIX "Can't use platform_notify\n");
 318                 return 0;
 319         }
 320         platform_notify = acpi_platform_notify;
 321         platform_notify_remove = acpi_platform_notify_remove;
 322         return 0;
 323 }