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