linux/drivers/acpi/container.c
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   1/*
   2 * acpi_container.c  - ACPI Generic Container Driver
   3 * ($Revision: )
   4 *
   5 * Copyright (C) 2004 Anil S Keshavamurthy (anil.s.keshavamurthy@intel.com)
   6 * Copyright (C) 2004 Keiichiro Tokunaga (tokunaga.keiich@jp.fujitsu.com)
   7 * Copyright (C) 2004 Motoyuki Ito (motoyuki@soft.fujitsu.com)
   8 * Copyright (C) 2004 Intel Corp.
   9 * Copyright (C) 2004 FUJITSU LIMITED
  10 *
  11 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  12 *
  13 *  This program is free software; you can redistribute it and/or modify
  14 *  it under the terms of the GNU General Public License as published by
  15 *  the Free Software Foundation; either version 2 of the License, or (at
  16 *  your option) any later version.
  17 *
  18 *  This program is distributed in the hope that it will be useful, but
  19 *  WITHOUT ANY WARRANTY; without even the implied warranty of
  20 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  21 *  General Public License for more details.
  22 *
  23 *  You should have received a copy of the GNU General Public License along
  24 *  with this program; if not, write to the Free Software Foundation, Inc.,
  25 *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  26 *
  27 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  28 */
  29#include <linux/kernel.h>
  30#include <linux/module.h>
  31#include <linux/init.h>
  32#include <linux/types.h>
  33#include <linux/acpi.h>
  34#include <acpi/acpi_bus.h>
  35#include <acpi/acpi_drivers.h>
  36#include <acpi/container.h>
  37
  38#define ACPI_CONTAINER_DEVICE_NAME      "ACPI container device"
  39#define ACPI_CONTAINER_CLASS            "container"
  40
  41#define INSTALL_NOTIFY_HANDLER          1
  42#define UNINSTALL_NOTIFY_HANDLER        2
  43
  44#define _COMPONENT                      ACPI_CONTAINER_COMPONENT
  45ACPI_MODULE_NAME("container");
  46
  47MODULE_AUTHOR("Anil S Keshavamurthy");
  48MODULE_DESCRIPTION("ACPI container driver");
  49MODULE_LICENSE("GPL");
  50
  51static int acpi_container_add(struct acpi_device *device);
  52static int acpi_container_remove(struct acpi_device *device, int type);
  53
  54static const struct acpi_device_id container_device_ids[] = {
  55        {"ACPI0004", 0},
  56        {"PNP0A05", 0},
  57        {"PNP0A06", 0},
  58        {"", 0},
  59};
  60MODULE_DEVICE_TABLE(acpi, container_device_ids);
  61
  62static struct acpi_driver acpi_container_driver = {
  63        .name = "container",
  64        .class = ACPI_CONTAINER_CLASS,
  65        .ids = container_device_ids,
  66        .ops = {
  67                .add = acpi_container_add,
  68                .remove = acpi_container_remove,
  69                },
  70};
  71
  72/*******************************************************************/
  73
  74static int is_device_present(acpi_handle handle)
  75{
  76        acpi_handle temp;
  77        acpi_status status;
  78        unsigned long long sta;
  79
  80
  81        status = acpi_get_handle(handle, "_STA", &temp);
  82        if (ACPI_FAILURE(status))
  83                return 1;       /* _STA not found, assume device present */
  84
  85        status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
  86        if (ACPI_FAILURE(status))
  87                return 0;       /* Firmware error */
  88
  89        return ((sta & ACPI_STA_DEVICE_PRESENT) == ACPI_STA_DEVICE_PRESENT);
  90}
  91
  92/*******************************************************************/
  93static int acpi_container_add(struct acpi_device *device)
  94{
  95        struct acpi_container *container;
  96
  97
  98        if (!device) {
  99                printk(KERN_ERR PREFIX "device is NULL\n");
 100                return -EINVAL;
 101        }
 102
 103        container = kzalloc(sizeof(struct acpi_container), GFP_KERNEL);
 104        if (!container)
 105                return -ENOMEM;
 106
 107        container->handle = device->handle;
 108        strcpy(acpi_device_name(device), ACPI_CONTAINER_DEVICE_NAME);
 109        strcpy(acpi_device_class(device), ACPI_CONTAINER_CLASS);
 110        device->driver_data = container;
 111
 112        ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device <%s> bid <%s>\n",
 113                          acpi_device_name(device), acpi_device_bid(device)));
 114
 115        return 0;
 116}
 117
 118static int acpi_container_remove(struct acpi_device *device, int type)
 119{
 120        acpi_status status = AE_OK;
 121        struct acpi_container *pc = NULL;
 122
 123        pc = acpi_driver_data(device);
 124        kfree(pc);
 125        return status;
 126}
 127
 128static int container_device_add(struct acpi_device **device, acpi_handle handle)
 129{
 130        acpi_handle phandle;
 131        struct acpi_device *pdev;
 132        int result;
 133
 134
 135        if (acpi_get_parent(handle, &phandle)) {
 136                return -ENODEV;
 137        }
 138
 139        if (acpi_bus_get_device(phandle, &pdev)) {
 140                return -ENODEV;
 141        }
 142
 143        if (acpi_bus_add(device, pdev, handle, ACPI_BUS_TYPE_DEVICE)) {
 144                return -ENODEV;
 145        }
 146
 147        result = acpi_bus_start(*device);
 148
 149        return result;
 150}
 151
 152static void container_notify_cb(acpi_handle handle, u32 type, void *context)
 153{
 154        struct acpi_device *device = NULL;
 155        int result;
 156        int present;
 157        acpi_status status;
 158
 159
 160        present = is_device_present(handle);
 161
 162        switch (type) {
 163        case ACPI_NOTIFY_BUS_CHECK:
 164                /* Fall through */
 165        case ACPI_NOTIFY_DEVICE_CHECK:
 166                printk(KERN_WARNING "Container driver received %s event\n",
 167                       (type == ACPI_NOTIFY_BUS_CHECK) ?
 168                       "ACPI_NOTIFY_BUS_CHECK" : "ACPI_NOTIFY_DEVICE_CHECK");
 169                status = acpi_bus_get_device(handle, &device);
 170                if (present) {
 171                        if (ACPI_FAILURE(status) || !device) {
 172                                result = container_device_add(&device, handle);
 173                                if (!result)
 174                                        kobject_uevent(&device->dev.kobj,
 175                                                       KOBJ_ONLINE);
 176                                else
 177                                        printk(KERN_WARNING
 178                                               "Failed to add container\n");
 179                        }
 180                } else {
 181                        if (ACPI_SUCCESS(status)) {
 182                                /* device exist and this is a remove request */
 183                                kobject_uevent(&device->dev.kobj, KOBJ_OFFLINE);
 184                        }
 185                }
 186                break;
 187        case ACPI_NOTIFY_EJECT_REQUEST:
 188                if (!acpi_bus_get_device(handle, &device) && device) {
 189                        kobject_uevent(&device->dev.kobj, KOBJ_OFFLINE);
 190                }
 191                break;
 192        default:
 193                break;
 194        }
 195        return;
 196}
 197
 198static acpi_status
 199container_walk_namespace_cb(acpi_handle handle,
 200                            u32 lvl, void *context, void **rv)
 201{
 202        char *hid = NULL;
 203        struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 204        struct acpi_device_info *info;
 205        acpi_status status;
 206        int *action = context;
 207
 208
 209        status = acpi_get_object_info(handle, &buffer);
 210        if (ACPI_FAILURE(status) || !buffer.pointer) {
 211                return AE_OK;
 212        }
 213
 214        info = buffer.pointer;
 215        if (info->valid & ACPI_VALID_HID)
 216                hid = info->hardware_id.value;
 217
 218        if (hid == NULL) {
 219                goto end;
 220        }
 221
 222        if (strcmp(hid, "ACPI0004") && strcmp(hid, "PNP0A05") &&
 223            strcmp(hid, "PNP0A06")) {
 224                goto end;
 225        }
 226
 227        switch (*action) {
 228        case INSTALL_NOTIFY_HANDLER:
 229                acpi_install_notify_handler(handle,
 230                                            ACPI_SYSTEM_NOTIFY,
 231                                            container_notify_cb, NULL);
 232                break;
 233        case UNINSTALL_NOTIFY_HANDLER:
 234                acpi_remove_notify_handler(handle,
 235                                           ACPI_SYSTEM_NOTIFY,
 236                                           container_notify_cb);
 237                break;
 238        default:
 239                break;
 240        }
 241
 242      end:
 243        kfree(buffer.pointer);
 244
 245        return AE_OK;
 246}
 247
 248static int __init acpi_container_init(void)
 249{
 250        int result = 0;
 251        int action = INSTALL_NOTIFY_HANDLER;
 252
 253        result = acpi_bus_register_driver(&acpi_container_driver);
 254        if (result < 0) {
 255                return (result);
 256        }
 257
 258        /* register notify handler to every container device */
 259        acpi_walk_namespace(ACPI_TYPE_DEVICE,
 260                            ACPI_ROOT_OBJECT,
 261                            ACPI_UINT32_MAX,
 262                            container_walk_namespace_cb, &action, NULL);
 263
 264        return (0);
 265}
 266
 267static void __exit acpi_container_exit(void)
 268{
 269        int action = UNINSTALL_NOTIFY_HANDLER;
 270
 271
 272        acpi_walk_namespace(ACPI_TYPE_DEVICE,
 273                            ACPI_ROOT_OBJECT,
 274                            ACPI_UINT32_MAX,
 275                            container_walk_namespace_cb, &action, NULL);
 276
 277        acpi_bus_unregister_driver(&acpi_container_driver);
 278
 279        return;
 280}
 281
 282module_init(acpi_container_init);
 283module_exit(acpi_container_exit);
 284