drivers/acpi/container.c

   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/slab.h>
  33 #include <linux/types.h>
  34 #include <linux/acpi.h>
  35 #include <acpi/acpi_bus.h>
  36 #include <acpi/acpi_drivers.h>
  37 #include <acpi/container.h>
  38
  39 #define PREFIX "ACPI: "
  40
  41 #define ACPI_CONTAINER_DEVICE_NAME      "ACPI container device"
  42 #define ACPI_CONTAINER_CLASS            "container"
  43
  44 #define INSTALL_NOTIFY_HANDLER          1
  45 #define UNINSTALL_NOTIFY_HANDLER        2
  46
  47 #define _COMPONENT                      ACPI_CONTAINER_COMPONENT
  48 ACPI_MODULE_NAME("container");
  49
  50 MODULE_AUTHOR("Anil S Keshavamurthy");
  51 MODULE_DESCRIPTION("ACPI container driver");
  52 MODULE_LICENSE("GPL");
  53
  54 static int acpi_container_add(struct acpi_device *device);
  55 static int acpi_container_remove(struct acpi_device *device);
  56
  57 static const struct acpi_device_id container_device_ids[] = {
  58         {"ACPI0004", 0},
  59         {"PNP0A05", 0},
  60         {"PNP0A06", 0},
  61         {"", 0},
  62 };
  63 MODULE_DEVICE_TABLE(acpi, container_device_ids);
  64
  65 static struct acpi_driver acpi_container_driver = {
  66         .name = "container",
  67         .class = ACPI_CONTAINER_CLASS,
  68         .ids = container_device_ids,
  69         .ops = {
  70                 .add = acpi_container_add,
  71                 .remove = acpi_container_remove,
  72                 },
  73 };
  74
  75 /*******************************************************************/
  76
  77 static int is_device_present(acpi_handle handle)
  78 {
  79         acpi_handle temp;
  80         acpi_status status;
  81         unsigned long long sta;
  82
  83
  84         status = acpi_get_handle(handle, "_STA", &temp);
  85         if (ACPI_FAILURE(status))
  86                 return 1;       /* _STA not found, assume device present */
  87
  88         status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
  89         if (ACPI_FAILURE(status))
  90                 return 0;       /* Firmware error */
  91
  92         return ((sta & ACPI_STA_DEVICE_PRESENT) == ACPI_STA_DEVICE_PRESENT);
  93 }
  94
  95 static bool is_container_device(const char *hid)
  96 {
  97         const struct acpi_device_id *container_id;
  98
  99         for (container_id = container_device_ids;
 100              container_id->id[0]; container_id++) {
 101                 if (!strcmp((char *)container_id->id, hid))
 102                         return true;
 103         }
 104
 105         return false;
 106 }
 107
 108 /*******************************************************************/
 109 static int acpi_container_add(struct acpi_device *device)
 110 {
 111         struct acpi_container *container;
 112
 113         container = kzalloc(sizeof(struct acpi_container), GFP_KERNEL);
 114         if (!container)
 115                 return -ENOMEM;
 116
 117         container->handle = device->handle;
 118         strcpy(acpi_device_name(device), ACPI_CONTAINER_DEVICE_NAME);
 119         strcpy(acpi_device_class(device), ACPI_CONTAINER_CLASS);
 120         device->driver_data = container;
 121
 122         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device <%s> bid <%s>\n",
 123                           acpi_device_name(device), acpi_device_bid(device)));
 124
 125         return 0;
 126 }
 127
 128 static int acpi_container_remove(struct acpi_device *device)
 129 {
 130         acpi_status status = AE_OK;
 131         struct acpi_container *pc = NULL;
 132
 133         pc = acpi_driver_data(device);
 134         kfree(pc);
 135         return status;
 136 }
 137
 138 static void container_notify_cb(acpi_handle handle, u32 type, void *context)
 139 {
 140         struct acpi_device *device = NULL;
 141         int result;
 142         int present;
 143         acpi_status status;
 144         u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE; /* default */
 145
 146         switch (type) {
 147         case ACPI_NOTIFY_BUS_CHECK:
 148                 /* Fall through */
 149         case ACPI_NOTIFY_DEVICE_CHECK:
 150                 pr_debug("Container driver received %s event\n",
 151                        (type == ACPI_NOTIFY_BUS_CHECK) ?
 152                        "ACPI_NOTIFY_BUS_CHECK" : "ACPI_NOTIFY_DEVICE_CHECK");
 153
 154                 present = is_device_present(handle);
 155                 status = acpi_bus_get_device(handle, &device);
 156                 if (!present) {
 157                         if (ACPI_SUCCESS(status)) {
 158                                 /* device exist and this is a remove request */
 159                                 device->flags.eject_pending = 1;
 160                                 kobject_uevent(&device->dev.kobj, KOBJ_OFFLINE);
 161                                 return;
 162                         }
 163                         break;
 164                 }
 165
 166                 if (!ACPI_FAILURE(status) || device)
 167                         break;
 168
 169                 result = acpi_bus_scan(handle);
 170                 if (result) {
 171                         acpi_handle_warn(handle, "Failed to add container\n");
 172                         break;
 173                 }
 174                 result = acpi_bus_get_device(handle, &device);
 175                 if (result) {
 176                         acpi_handle_warn(handle, "Missing device object\n");
 177                         break;
 178                 }
 179
 180                 kobject_uevent(&device->dev.kobj, KOBJ_ONLINE);
 181                 ost_code = ACPI_OST_SC_SUCCESS;
 182                 break;
 183
 184         case ACPI_NOTIFY_EJECT_REQUEST:
 185                 if (!acpi_bus_get_device(handle, &device) && device) {
 186                         device->flags.eject_pending = 1;
 187                         kobject_uevent(&device->dev.kobj, KOBJ_OFFLINE);
 188                         return;
 189                 }
 190                 break;
 191
 192         default:
 193                 /* non-hotplug event; possibly handled by other handler */
 194                 return;
 195         }
 196
 197         /* Inform firmware that the hotplug operation has completed */
 198         (void) acpi_evaluate_hotplug_ost(handle, type, ost_code, NULL);
 199         return;
 200 }
 201
 202 static acpi_status
 203 container_walk_namespace_cb(acpi_handle handle,
 204                             u32 lvl, void *context, void **rv)
 205 {
 206         char *hid = NULL;
 207         struct acpi_device_info *info;
 208         acpi_status status;
 209         int *action = context;
 210
 211         status = acpi_get_object_info(handle, &info);
 212         if (ACPI_FAILURE(status)) {
 213                 return AE_OK;
 214         }
 215
 216         if (info->valid & ACPI_VALID_HID)
 217                 hid = info->hardware_id.string;
 218
 219         if (hid == NULL) {
 220                 goto end;
 221         }
 222
 223         if (!is_container_device(hid))
 224                 goto end;
 225
 226         switch (*action) {
 227         case INSTALL_NOTIFY_HANDLER:
 228                 acpi_install_notify_handler(handle,
 229                                             ACPI_SYSTEM_NOTIFY,
 230                                             container_notify_cb, NULL);
 231                 break;
 232         case UNINSTALL_NOTIFY_HANDLER:
 233                 acpi_remove_notify_handler(handle,
 234                                            ACPI_SYSTEM_NOTIFY,
 235                                            container_notify_cb);
 236                 break;
 237         default:
 238                 break;
 239         }
 240
 241       end:
 242         kfree(info);
 243
 244         return AE_OK;
 245 }
 246
 247 static int __init acpi_container_init(void)
 248 {
 249         int result = 0;
 250         int action = INSTALL_NOTIFY_HANDLER;
 251
 252         result = acpi_bus_register_driver(&acpi_container_driver);
 253         if (result < 0) {
 254                 return (result);
 255         }
 256
 257         /* register notify handler to every container device */
 258         acpi_walk_namespace(ACPI_TYPE_DEVICE,
 259                             ACPI_ROOT_OBJECT,
 260                             ACPI_UINT32_MAX,
 261                             container_walk_namespace_cb, NULL, &action, NULL);
 262
 263         return (0);
 264 }
 265
 266 static void __exit acpi_container_exit(void)
 267 {
 268         int action = UNINSTALL_NOTIFY_HANDLER;
 269
 270
 271         acpi_walk_namespace(ACPI_TYPE_DEVICE,
 272                             ACPI_ROOT_OBJECT,
 273                             ACPI_UINT32_MAX,
 274                             container_walk_namespace_cb, NULL, &action, NULL);
 275
 276         acpi_bus_unregister_driver(&acpi_container_driver);
 277
 278         return;
 279 }
 280
 281 module_init(acpi_container_init);
 282 module_exit(acpi_container_exit);