drivers/acpi/video.c

   1 /*
   2  *  video.c - ACPI Video Driver
   3  *
   4  *  Copyright (C) 2004 Luming Yu <luming.yu@intel.com>
   5  *  Copyright (C) 2004 Bruno Ducrot <ducrot@poupinou.org>
   6  *  Copyright (C) 2006 Thomas Tuttle <linux-kernel@ttuttle.net>
   7  *
   8  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   9  *
  10  *  This program is free software; you can redistribute it and/or modify
  11  *  it under the terms of the GNU General Public License as published by
  12  *  the Free Software Foundation; either version 2 of the License, or (at
  13  *  your option) any later version.
  14  *
  15  *  This program is distributed in the hope that it will be useful, but
  16  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  17  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  *  General Public License for more details.
  19  *
  20  *  You should have received a copy of the GNU General Public License along
  21  *  with this program; if not, write to the Free Software Foundation, Inc.,
  22  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  23  *
  24  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  25  */
  26
  27 #include <linux/kernel.h>
  28 #include <linux/module.h>
  29 #include <linux/init.h>
  30 #include <linux/types.h>
  31 #include <linux/list.h>
  32 #include <linux/mutex.h>
  33 #include <linux/input.h>
  34 #include <linux/backlight.h>
  35 #include <linux/thermal.h>
  36 #include <linux/sort.h>
  37 #include <linux/pci.h>
  38 #include <linux/pci_ids.h>
  39 #include <linux/slab.h>
  40 #include <linux/dmi.h>
  41 #include <linux/suspend.h>
  42 #include <linux/acpi.h>
  43 #include <acpi/video.h>
  44 #include <asm/uaccess.h>
  45
  46 #include "internal.h"
  47
  48 #define ACPI_VIDEO_BUS_NAME             "Video Bus"
  49 #define ACPI_VIDEO_DEVICE_NAME          "Video Device"
  50 #define ACPI_VIDEO_NOTIFY_SWITCH        0x80
  51 #define ACPI_VIDEO_NOTIFY_PROBE         0x81
  52 #define ACPI_VIDEO_NOTIFY_CYCLE         0x82
  53 #define ACPI_VIDEO_NOTIFY_NEXT_OUTPUT   0x83
  54 #define ACPI_VIDEO_NOTIFY_PREV_OUTPUT   0x84
  55
  56 #define ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS      0x85
  57 #define ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS        0x86
  58 #define ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS        0x87
  59 #define ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS       0x88
  60 #define ACPI_VIDEO_NOTIFY_DISPLAY_OFF           0x89
  61
  62 #define MAX_NAME_LEN    20
  63
  64 #define _COMPONENT              ACPI_VIDEO_COMPONENT
  65 ACPI_MODULE_NAME("video");
  66
  67 MODULE_AUTHOR("Bruno Ducrot");
  68 MODULE_DESCRIPTION("ACPI Video Driver");
  69 MODULE_LICENSE("GPL");
  70
  71 static bool brightness_switch_enabled = 1;
  72 module_param(brightness_switch_enabled, bool, 0644);
  73
  74 /*
  75  * By default, we don't allow duplicate ACPI video bus devices
  76  * under the same VGA controller
  77  */
  78 static bool allow_duplicates;
  79 module_param(allow_duplicates, bool, 0644);
  80
  81 /*
  82  * For Windows 8 systems: used to decide if video module
  83  * should skip registering backlight interface of its own.
  84  */
  85 static int use_native_backlight_param = 1;
  86 module_param_named(use_native_backlight, use_native_backlight_param, int, 0444);
  87 static bool use_native_backlight_dmi = false;
  88
  89 static int register_count;
  90 static struct mutex video_list_lock;
  91 static struct list_head video_bus_head;
  92 static int acpi_video_bus_add(struct acpi_device *device);
  93 static int acpi_video_bus_remove(struct acpi_device *device);
  94 static void acpi_video_bus_notify(struct acpi_device *device, u32 event);
  95
  96 static const struct acpi_device_id video_device_ids[] = {
  97         {ACPI_VIDEO_HID, 0},
  98         {"", 0},
  99 };
 100 MODULE_DEVICE_TABLE(acpi, video_device_ids);
 101
 102 static struct acpi_driver acpi_video_bus = {
 103         .name = "video",
 104         .class = ACPI_VIDEO_CLASS,
 105         .ids = video_device_ids,
 106         .ops = {
 107                 .add = acpi_video_bus_add,
 108                 .remove = acpi_video_bus_remove,
 109                 .notify = acpi_video_bus_notify,
 110                 },
 111 };
 112
 113 struct acpi_video_bus_flags {
 114         u8 multihead:1;         /* can switch video heads */
 115         u8 rom:1;               /* can retrieve a video rom */
 116         u8 post:1;              /* can configure the head to */
 117         u8 reserved:5;
 118 };
 119
 120 struct acpi_video_bus_cap {
 121         u8 _DOS:1;              /* Enable/Disable output switching */
 122         u8 _DOD:1;              /* Enumerate all devices attached to display adapter */
 123         u8 _ROM:1;              /* Get ROM Data */
 124         u8 _GPD:1;              /* Get POST Device */
 125         u8 _SPD:1;              /* Set POST Device */
 126         u8 _VPO:1;              /* Video POST Options */
 127         u8 reserved:2;
 128 };
 129
 130 struct acpi_video_device_attrib {
 131         u32 display_index:4;    /* A zero-based instance of the Display */
 132         u32 display_port_attachment:4;  /* This field differentiates the display type */
 133         u32 display_type:4;     /* Describe the specific type in use */
 134         u32 vendor_specific:4;  /* Chipset Vendor Specific */
 135         u32 bios_can_detect:1;  /* BIOS can detect the device */
 136         u32 depend_on_vga:1;    /* Non-VGA output device whose power is related to
 137                                    the VGA device. */
 138         u32 pipe_id:3;          /* For VGA multiple-head devices. */
 139         u32 reserved:10;        /* Must be 0 */
 140         u32 device_id_scheme:1; /* Device ID Scheme */
 141 };
 142
 143 struct acpi_video_enumerated_device {
 144         union {
 145                 u32 int_val;
 146                 struct acpi_video_device_attrib attrib;
 147         } value;
 148         struct acpi_video_device *bind_info;
 149 };
 150
 151 struct acpi_video_bus {
 152         struct acpi_device *device;
 153         bool backlight_registered;
 154         bool backlight_notifier_registered;
 155         u8 dos_setting;
 156         struct acpi_video_enumerated_device *attached_array;
 157         u8 attached_count;
 158         struct acpi_video_bus_cap cap;
 159         struct acpi_video_bus_flags flags;
 160         struct list_head video_device_list;
 161         struct mutex device_list_lock;  /* protects video_device_list */
 162         struct list_head entry;
 163         struct input_dev *input;
 164         char phys[32];  /* for input device */
 165         struct notifier_block pm_nb;
 166         struct notifier_block backlight_nb;
 167 };
 168
 169 struct acpi_video_device_flags {
 170         u8 crt:1;
 171         u8 lcd:1;
 172         u8 tvout:1;
 173         u8 dvi:1;
 174         u8 bios:1;
 175         u8 unknown:1;
 176         u8 notify:1;
 177         u8 reserved:1;
 178 };
 179
 180 struct acpi_video_device_cap {
 181         u8 _ADR:1;              /* Return the unique ID */
 182         u8 _BCL:1;              /* Query list of brightness control levels supported */
 183         u8 _BCM:1;              /* Set the brightness level */
 184         u8 _BQC:1;              /* Get current brightness level */
 185         u8 _BCQ:1;              /* Some buggy BIOS uses _BCQ instead of _BQC */
 186         u8 _DDC:1;              /* Return the EDID for this device */
 187 };
 188
 189 struct acpi_video_brightness_flags {
 190         u8 _BCL_no_ac_battery_levels:1; /* no AC/Battery levels in _BCL */
 191         u8 _BCL_reversed:1;             /* _BCL package is in a reversed order */
 192         u8 _BQC_use_index:1;            /* _BQC returns an index value */
 193 };
 194
 195 struct acpi_video_device_brightness {
 196         int curr;
 197         int count;
 198         int *levels;
 199         struct acpi_video_brightness_flags flags;
 200 };
 201
 202 struct acpi_video_device {
 203         unsigned long device_id;
 204         struct acpi_video_device_flags flags;
 205         struct acpi_video_device_cap cap;
 206         struct list_head entry;
 207         struct acpi_video_bus *video;
 208         struct acpi_device *dev;
 209         struct acpi_video_device_brightness *brightness;
 210         struct backlight_device *backlight;
 211         struct thermal_cooling_device *cooling_dev;
 212 };
 213
 214 static const char device_decode[][30] = {
 215         "motherboard VGA device",
 216         "PCI VGA device",
 217         "AGP VGA device",
 218         "UNKNOWN",
 219 };
 220
 221 static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data);
 222 static void acpi_video_device_rebind(struct acpi_video_bus *video);
 223 static void acpi_video_device_bind(struct acpi_video_bus *video,
 224                                    struct acpi_video_device *device);
 225 static int acpi_video_device_enumerate(struct acpi_video_bus *video);
 226 static int acpi_video_device_lcd_set_level(struct acpi_video_device *device,
 227                         int level);
 228 static int acpi_video_device_lcd_get_level_current(
 229                         struct acpi_video_device *device,
 230                         unsigned long long *level, bool raw);
 231 static int acpi_video_get_next_level(struct acpi_video_device *device,
 232                                      u32 level_current, u32 event);
 233 static int acpi_video_switch_brightness(struct acpi_video_device *device,
 234                                          int event);
 235
 236 static bool acpi_video_use_native_backlight(void)
 237 {
 238         if (use_native_backlight_param != -1)
 239                 return use_native_backlight_param;
 240         else
 241                 return use_native_backlight_dmi;
 242 }
 243
 244 bool acpi_video_verify_backlight_support(void)
 245 {
 246         if (acpi_osi_is_win8() && acpi_video_use_native_backlight() &&
 247             backlight_device_registered(BACKLIGHT_RAW))
 248                 return false;
 249         return acpi_video_backlight_support();
 250 }
 251 EXPORT_SYMBOL_GPL(acpi_video_verify_backlight_support);
 252
 253 /* backlight device sysfs support */
 254 static int acpi_video_get_brightness(struct backlight_device *bd)
 255 {
 256         unsigned long long cur_level;
 257         int i;
 258         struct acpi_video_device *vd = bl_get_data(bd);
 259
 260         if (acpi_video_device_lcd_get_level_current(vd, &cur_level, false))
 261                 return -EINVAL;
 262         for (i = 2; i < vd->brightness->count; i++) {
 263                 if (vd->brightness->levels[i] == cur_level)
 264                         /*
 265                          * The first two entries are special - see page 575
 266                          * of the ACPI spec 3.0
 267                          */
 268                         return i - 2;
 269         }
 270         return 0;
 271 }
 272
 273 static int acpi_video_set_brightness(struct backlight_device *bd)
 274 {
 275         int request_level = bd->props.brightness + 2;
 276         struct acpi_video_device *vd = bl_get_data(bd);
 277
 278         return acpi_video_device_lcd_set_level(vd,
 279                                 vd->brightness->levels[request_level]);
 280 }
 281
 282 static const struct backlight_ops acpi_backlight_ops = {
 283         .get_brightness = acpi_video_get_brightness,
 284         .update_status  = acpi_video_set_brightness,
 285 };
 286
 287 /* thermal cooling device callbacks */
 288 static int video_get_max_state(struct thermal_cooling_device *cooling_dev, unsigned
 289                                long *state)
 290 {
 291         struct acpi_device *device = cooling_dev->devdata;
 292         struct acpi_video_device *video = acpi_driver_data(device);
 293
 294         *state = video->brightness->count - 3;
 295         return 0;
 296 }
 297
 298 static int video_get_cur_state(struct thermal_cooling_device *cooling_dev, unsigned
 299                                long *state)
 300 {
 301         struct acpi_device *device = cooling_dev->devdata;
 302         struct acpi_video_device *video = acpi_driver_data(device);
 303         unsigned long long level;
 304         int offset;
 305
 306         if (acpi_video_device_lcd_get_level_current(video, &level, false))
 307                 return -EINVAL;
 308         for (offset = 2; offset < video->brightness->count; offset++)
 309                 if (level == video->brightness->levels[offset]) {
 310                         *state = video->brightness->count - offset - 1;
 311                         return 0;
 312                 }
 313
 314         return -EINVAL;
 315 }
 316
 317 static int
 318 video_set_cur_state(struct thermal_cooling_device *cooling_dev, unsigned long state)
 319 {
 320         struct acpi_device *device = cooling_dev->devdata;
 321         struct acpi_video_device *video = acpi_driver_data(device);
 322         int level;
 323
 324         if (state >= video->brightness->count - 2)
 325                 return -EINVAL;
 326
 327         state = video->brightness->count - state;
 328         level = video->brightness->levels[state - 1];
 329         return acpi_video_device_lcd_set_level(video, level);
 330 }
 331
 332 static const struct thermal_cooling_device_ops video_cooling_ops = {
 333         .get_max_state = video_get_max_state,
 334         .get_cur_state = video_get_cur_state,
 335         .set_cur_state = video_set_cur_state,
 336 };
 337
 338 /*
 339  * --------------------------------------------------------------------------
 340  *                             Video Management
 341  * --------------------------------------------------------------------------
 342  */
 343
 344 static int
 345 acpi_video_device_lcd_query_levels(struct acpi_video_device *device,
 346                                    union acpi_object **levels)
 347 {
 348         int status;
 349         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 350         union acpi_object *obj;
 351
 352
 353         *levels = NULL;
 354
 355         status = acpi_evaluate_object(device->dev->handle, "_BCL", NULL, &buffer);
 356         if (!ACPI_SUCCESS(status))
 357                 return status;
 358         obj = (union acpi_object *)buffer.pointer;
 359         if (!obj || (obj->type != ACPI_TYPE_PACKAGE)) {
 360                 printk(KERN_ERR PREFIX "Invalid _BCL data\n");
 361                 status = -EFAULT;
 362                 goto err;
 363         }
 364
 365         *levels = obj;
 366
 367         return 0;
 368
 369 err:
 370         kfree(buffer.pointer);
 371
 372         return status;
 373 }
 374
 375 static int
 376 acpi_video_device_lcd_set_level(struct acpi_video_device *device, int level)
 377 {
 378         int status;
 379         int state;
 380
 381         status = acpi_execute_simple_method(device->dev->handle,
 382                                             "_BCM", level);
 383         if (ACPI_FAILURE(status)) {
 384                 ACPI_ERROR((AE_INFO, "Evaluating _BCM failed"));
 385                 return -EIO;
 386         }
 387
 388         device->brightness->curr = level;
 389         for (state = 2; state < device->brightness->count; state++)
 390                 if (level == device->brightness->levels[state]) {
 391                         if (device->backlight)
 392                                 device->backlight->props.brightness = state - 2;
 393                         return 0;
 394                 }
 395
 396         ACPI_ERROR((AE_INFO, "Current brightness invalid"));
 397         return -EINVAL;
 398 }
 399
 400 /*
 401  * For some buggy _BQC methods, we need to add a constant value to
 402  * the _BQC return value to get the actual current brightness level
 403  */
 404
 405 static int bqc_offset_aml_bug_workaround;
 406 static int __init video_set_bqc_offset(const struct dmi_system_id *d)
 407 {
 408         bqc_offset_aml_bug_workaround = 9;
 409         return 0;
 410 }
 411
 412 static int __init video_set_use_native_backlight(const struct dmi_system_id *d)
 413 {
 414         use_native_backlight_dmi = true;
 415         return 0;
 416 }
 417
 418 static struct dmi_system_id video_dmi_table[] __initdata = {
 419         /*
 420          * Broken _BQC workaround http://bugzilla.kernel.org/show_bug.cgi?id=13121
 421          */
 422         {
 423          .callback = video_set_bqc_offset,
 424          .ident = "Acer Aspire 5720",
 425          .matches = {
 426                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
 427                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5720"),
 428                 },
 429         },
 430         {
 431          .callback = video_set_bqc_offset,
 432          .ident = "Acer Aspire 5710Z",
 433          .matches = {
 434                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
 435                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5710Z"),
 436                 },
 437         },
 438         {
 439          .callback = video_set_bqc_offset,
 440          .ident = "eMachines E510",
 441          .matches = {
 442                 DMI_MATCH(DMI_BOARD_VENDOR, "EMACHINES"),
 443                 DMI_MATCH(DMI_PRODUCT_NAME, "eMachines E510"),
 444                 },
 445         },
 446         {
 447          .callback = video_set_bqc_offset,
 448          .ident = "Acer Aspire 5315",
 449          .matches = {
 450                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
 451                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5315"),
 452                 },
 453         },
 454         {
 455          .callback = video_set_bqc_offset,
 456          .ident = "Acer Aspire 7720",
 457          .matches = {
 458                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
 459                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 7720"),
 460                 },
 461         },
 462         {
 463          .callback = video_set_use_native_backlight,
 464          .ident = "ThinkPad T430 and T430s",
 465          .matches = {
 466                 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
 467                 DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T430"),
 468                 },
 469         },
 470         {
 471          .callback = video_set_use_native_backlight,
 472          .ident = "ThinkPad X230",
 473          .matches = {
 474                 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
 475                 DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X230"),
 476                 },
 477         },
 478         {
 479          .callback = video_set_use_native_backlight,
 480          .ident = "ThinkPad W530",
 481          .matches = {
 482                 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
 483                 DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad W530"),
 484                 },
 485         },
 486         {
 487          .callback = video_set_use_native_backlight,
 488         .ident = "ThinkPad X1 Carbon",
 489         .matches = {
 490                 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
 491                 DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X1 Carbon"),
 492                 },
 493         },
 494         {
 495          .callback = video_set_use_native_backlight,
 496          .ident = "Lenovo Yoga 13",
 497          .matches = {
 498                 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
 499                 DMI_MATCH(DMI_PRODUCT_VERSION, "Lenovo IdeaPad Yoga 13"),
 500                 },
 501         },
 502         {
 503          .callback = video_set_use_native_backlight,
 504          .ident = "Lenovo Yoga 2 11",
 505          .matches = {
 506                 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
 507                 DMI_MATCH(DMI_PRODUCT_VERSION, "Lenovo Yoga 2 11"),
 508                 },
 509         },
 510         {
 511         .callback = video_set_use_native_backlight,
 512         .ident = "Thinkpad Helix",
 513         .matches = {
 514                 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
 515                 DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad Helix"),
 516                 },
 517         },
 518         {
 519          .callback = video_set_use_native_backlight,
 520          .ident = "Dell Inspiron 7520",
 521          .matches = {
 522                 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 523                 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 7520"),
 524                 },
 525         },
 526         {
 527          .callback = video_set_use_native_backlight,
 528          .ident = "Acer Aspire 5733Z",
 529          .matches = {
 530                 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
 531                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5733Z"),
 532                 },
 533         },
 534         {
 535          .callback = video_set_use_native_backlight,
 536          .ident = "Acer Aspire 5742G",
 537          .matches = {
 538                 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
 539                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5742G"),
 540                 },
 541         },
 542         {
 543          .callback = video_set_use_native_backlight,
 544          .ident = "Acer Aspire V5-171",
 545          .matches = {
 546                 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
 547                 DMI_MATCH(DMI_PRODUCT_NAME, "V5-171"),
 548                 },
 549         },
 550         {
 551          .callback = video_set_use_native_backlight,
 552          .ident = "Acer Aspire V5-431",
 553          .matches = {
 554                 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
 555                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire V5-431"),
 556                 },
 557         },
 558         {
 559          .callback = video_set_use_native_backlight,
 560          .ident = "Acer Aspire V5-471G",
 561          .matches = {
 562                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
 563                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire V5-471G"),
 564                 },
 565         },
 566         {
 567          .callback = video_set_use_native_backlight,
 568          .ident = "Acer TravelMate B113",
 569          .matches = {
 570                 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
 571                 DMI_MATCH(DMI_PRODUCT_NAME, "TravelMate B113"),
 572                 },
 573         },
 574         {
 575         .callback = video_set_use_native_backlight,
 576         .ident = "HP ProBook 4340s",
 577         .matches = {
 578                 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
 579                 DMI_MATCH(DMI_PRODUCT_VERSION, "HP ProBook 4340s"),
 580                 },
 581         },
 582         {
 583         .callback = video_set_use_native_backlight,
 584         .ident = "HP ProBook 4540s",
 585         .matches = {
 586                 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
 587                 DMI_MATCH(DMI_PRODUCT_VERSION, "HP ProBook 4540s"),
 588                 },
 589         },
 590         {
 591         .callback = video_set_use_native_backlight,
 592         .ident = "HP ProBook 2013 models",
 593         .matches = {
 594                 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
 595                 DMI_MATCH(DMI_PRODUCT_NAME, "HP ProBook "),
 596                 DMI_MATCH(DMI_PRODUCT_NAME, " G1"),
 597                 },
 598         },
 599         {
 600         .callback = video_set_use_native_backlight,
 601         .ident = "HP EliteBook 2013 models",
 602         .matches = {
 603                 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
 604                 DMI_MATCH(DMI_PRODUCT_NAME, "HP EliteBook "),
 605                 DMI_MATCH(DMI_PRODUCT_NAME, " G1"),
 606                 },
 607         },
 608         {
 609         .callback = video_set_use_native_backlight,
 610         .ident = "HP ZBook 14",
 611         .matches = {
 612                 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
 613                 DMI_MATCH(DMI_PRODUCT_NAME, "HP ZBook 14"),
 614                 },
 615         },
 616         {
 617         .callback = video_set_use_native_backlight,
 618         .ident = "HP ZBook 15",
 619         .matches = {
 620                 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
 621                 DMI_MATCH(DMI_PRODUCT_NAME, "HP ZBook 15"),
 622                 },
 623         },
 624         {
 625         .callback = video_set_use_native_backlight,
 626         .ident = "HP ZBook 17",
 627         .matches = {
 628                 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
 629                 DMI_MATCH(DMI_PRODUCT_NAME, "HP ZBook 17"),
 630                 },
 631         },
 632         {
 633         .callback = video_set_use_native_backlight,
 634         .ident = "HP EliteBook 8470p",
 635         .matches = {
 636                 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
 637                 DMI_MATCH(DMI_PRODUCT_NAME, "HP EliteBook 8470p"),
 638                 },
 639         },
 640         {
 641         .callback = video_set_use_native_backlight,
 642         .ident = "HP EliteBook 8780w",
 643         .matches = {
 644                 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
 645                 DMI_MATCH(DMI_PRODUCT_NAME, "HP EliteBook 8780w"),
 646                 },
 647         },
 648         {}
 649 };
 650
 651 static unsigned long long
 652 acpi_video_bqc_value_to_level(struct acpi_video_device *device,
 653                               unsigned long long bqc_value)
 654 {
 655         unsigned long long level;
 656
 657         if (device->brightness->flags._BQC_use_index) {
 658                 /*
 659                  * _BQC returns an index that doesn't account for
 660                  * the first 2 items with special meaning, so we need
 661                  * to compensate for that by offsetting ourselves
 662                  */
 663                 if (device->brightness->flags._BCL_reversed)
 664                         bqc_value = device->brightness->count - 3 - bqc_value;
 665
 666                 level = device->brightness->levels[bqc_value + 2];
 667         } else {
 668                 level = bqc_value;
 669         }
 670
 671         level += bqc_offset_aml_bug_workaround;
 672
 673         return level;
 674 }
 675
 676 static int
 677 acpi_video_device_lcd_get_level_current(struct acpi_video_device *device,
 678                                         unsigned long long *level, bool raw)
 679 {
 680         acpi_status status = AE_OK;
 681         int i;
 682
 683         if (device->cap._BQC || device->cap._BCQ) {
 684                 char *buf = device->cap._BQC ? "_BQC" : "_BCQ";
 685
 686                 status = acpi_evaluate_integer(device->dev->handle, buf,
 687                                                 NULL, level);
 688                 if (ACPI_SUCCESS(status)) {
 689                         if (raw) {
 690                                 /*
 691                                  * Caller has indicated he wants the raw
 692                                  * value returned by _BQC, so don't furtherly
 693                                  * mess with the value.
 694                                  */
 695                                 return 0;
 696                         }
 697
 698                         *level = acpi_video_bqc_value_to_level(device, *level);
 699
 700                         for (i = 2; i < device->brightness->count; i++)
 701                                 if (device->brightness->levels[i] == *level) {
 702                                         device->brightness->curr = *level;
 703                                         return 0;
 704                                 }
 705                         /*
 706                          * BQC returned an invalid level.
 707                          * Stop using it.
 708                          */
 709                         ACPI_WARNING((AE_INFO,
 710                                       "%s returned an invalid level",
 711                                       buf));
 712                         device->cap._BQC = device->cap._BCQ = 0;
 713                 } else {
 714                         /*
 715                          * Fixme:
 716                          * should we return an error or ignore this failure?
 717                          * dev->brightness->curr is a cached value which stores
 718                          * the correct current backlight level in most cases.
 719                          * ACPI video backlight still works w/ buggy _BQC.
 720                          * http://bugzilla.kernel.org/show_bug.cgi?id=12233
 721                          */
 722                         ACPI_WARNING((AE_INFO, "Evaluating %s failed", buf));
 723                         device->cap._BQC = device->cap._BCQ = 0;
 724                 }
 725         }
 726
 727         *level = device->brightness->curr;
 728         return 0;
 729 }
 730
 731 static int
 732 acpi_video_device_EDID(struct acpi_video_device *device,
 733                        union acpi_object **edid, ssize_t length)
 734 {
 735         int status;
 736         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 737         union acpi_object *obj;
 738         union acpi_object arg0 = { ACPI_TYPE_INTEGER };
 739         struct acpi_object_list args = { 1, &arg0 };
 740
 741
 742         *edid = NULL;
 743
 744         if (!device)
 745                 return -ENODEV;
 746         if (length == 128)
 747                 arg0.integer.value = 1;
 748         else if (length == 256)
 749                 arg0.integer.value = 2;
 750         else
 751                 return -EINVAL;
 752
 753         status = acpi_evaluate_object(device->dev->handle, "_DDC", &args, &buffer);
 754         if (ACPI_FAILURE(status))
 755                 return -ENODEV;
 756
 757         obj = buffer.pointer;
 758
 759         if (obj && obj->type == ACPI_TYPE_BUFFER)
 760                 *edid = obj;
 761         else {
 762                 printk(KERN_ERR PREFIX "Invalid _DDC data\n");
 763                 status = -EFAULT;
 764                 kfree(obj);
 765         }
 766
 767         return status;
 768 }
 769
 770 /* bus */
 771
 772 /*
 773  *  Arg:
 774  *      video           : video bus device pointer
 775  *      bios_flag       :
 776  *              0.      The system BIOS should NOT automatically switch(toggle)
 777  *                      the active display output.
 778  *              1.      The system BIOS should automatically switch (toggle) the
 779  *                      active display output. No switch event.
 780  *              2.      The _DGS value should be locked.
 781  *              3.      The system BIOS should not automatically switch (toggle) the
 782  *                      active display output, but instead generate the display switch
 783  *                      event notify code.
 784  *      lcd_flag        :
 785  *              0.      The system BIOS should automatically control the brightness level
 786  *                      of the LCD when the power changes from AC to DC
 787  *              1.      The system BIOS should NOT automatically control the brightness
 788  *                      level of the LCD when the power changes from AC to DC.
 789  *  Return Value:
 790  *              -EINVAL wrong arg.
 791  */
 792
 793 static int
 794 acpi_video_bus_DOS(struct acpi_video_bus *video, int bios_flag, int lcd_flag)
 795 {
 796         acpi_status status;
 797
 798         if (!video->cap._DOS)
 799                 return 0;
 800
 801         if (bios_flag < 0 || bios_flag > 3 || lcd_flag < 0 || lcd_flag > 1)
 802                 return -EINVAL;
 803         video->dos_setting = (lcd_flag << 2) | bios_flag;
 804         status = acpi_execute_simple_method(video->device->handle, "_DOS",
 805                                             (lcd_flag << 2) | bios_flag);
 806         if (ACPI_FAILURE(status))
 807                 return -EIO;
 808
 809         return 0;
 810 }
 811
 812 /*
 813  * Simple comparison function used to sort backlight levels.
 814  */
 815
 816 static int
 817 acpi_video_cmp_level(const void *a, const void *b)
 818 {
 819         return *(int *)a - *(int *)b;
 820 }
 821
 822 /*
 823  * Decides if _BQC/_BCQ for this system is usable
 824  *
 825  * We do this by changing the level first and then read out the current
 826  * brightness level, if the value does not match, find out if it is using
 827  * index. If not, clear the _BQC/_BCQ capability.
 828  */
 829 static int acpi_video_bqc_quirk(struct acpi_video_device *device,
 830                                 int max_level, int current_level)
 831 {
 832         struct acpi_video_device_brightness *br = device->brightness;
 833         int result;
 834         unsigned long long level;
 835         int test_level;
 836
 837         /* don't mess with existing known broken systems */
 838         if (bqc_offset_aml_bug_workaround)
 839                 return 0;
 840
 841         /*
 842          * Some systems always report current brightness level as maximum
 843          * through _BQC, we need to test another value for them.
 844          */
 845         test_level = current_level == max_level ? br->levels[3] : max_level;
 846
 847         result = acpi_video_device_lcd_set_level(device, test_level);
 848         if (result)
 849                 return result;
 850
 851         result = acpi_video_device_lcd_get_level_current(device, &level, true);
 852         if (result)
 853                 return result;
 854
 855         if (level != test_level) {
 856                 /* buggy _BQC found, need to find out if it uses index */
 857                 if (level < br->count) {
 858                         if (br->flags._BCL_reversed)
 859                                 level = br->count - 3 - level;
 860                         if (br->levels[level + 2] == test_level)
 861                                 br->flags._BQC_use_index = 1;
 862                 }
 863
 864                 if (!br->flags._BQC_use_index)
 865                         device->cap._BQC = device->cap._BCQ = 0;
 866         }
 867
 868         return 0;
 869 }
 870
 871
 872 /*
 873  *  Arg:
 874  *      device  : video output device (LCD, CRT, ..)
 875  *
 876  *  Return Value:
 877  *      Maximum brightness level
 878  *
 879  *  Allocate and initialize device->brightness.
 880  */
 881
 882 static int
 883 acpi_video_init_brightness(struct acpi_video_device *device)
 884 {
 885         union acpi_object *obj = NULL;
 886         int i, max_level = 0, count = 0, level_ac_battery = 0;
 887         unsigned long long level, level_old;
 888         union acpi_object *o;
 889         struct acpi_video_device_brightness *br = NULL;
 890         int result = -EINVAL;
 891         u32 value;
 892
 893         if (!ACPI_SUCCESS(acpi_video_device_lcd_query_levels(device, &obj))) {
 894                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Could not query available "
 895                                                 "LCD brightness level\n"));
 896                 goto out;
 897         }
 898
 899         if (obj->package.count < 2)
 900                 goto out;
 901
 902         br = kzalloc(sizeof(*br), GFP_KERNEL);
 903         if (!br) {
 904                 printk(KERN_ERR "can't allocate memory\n");
 905                 result = -ENOMEM;
 906                 goto out;
 907         }
 908
 909         br->levels = kmalloc((obj->package.count + 2) * sizeof *(br->levels),
 910                                 GFP_KERNEL);
 911         if (!br->levels) {
 912                 result = -ENOMEM;
 913                 goto out_free;
 914         }
 915
 916         for (i = 0; i < obj->package.count; i++) {
 917                 o = (union acpi_object *)&obj->package.elements[i];
 918                 if (o->type != ACPI_TYPE_INTEGER) {
 919                         printk(KERN_ERR PREFIX "Invalid data\n");
 920                         continue;
 921                 }
 922                 value = (u32) o->integer.value;
 923                 /* Skip duplicate entries */
 924                 if (count > 2 && br->levels[count - 1] == value)
 925                         continue;
 926
 927                 br->levels[count] = value;
 928
 929                 if (br->levels[count] > max_level)
 930                         max_level = br->levels[count];
 931                 count++;
 932         }
 933
 934         /*
 935          * some buggy BIOS don't export the levels
 936          * when machine is on AC/Battery in _BCL package.
 937          * In this case, the first two elements in _BCL packages
 938          * are also supported brightness levels that OS should take care of.
 939          */
 940         for (i = 2; i < count; i++) {
 941                 if (br->levels[i] == br->levels[0])
 942                         level_ac_battery++;
 943                 if (br->levels[i] == br->levels[1])
 944                         level_ac_battery++;
 945         }
 946
 947         if (level_ac_battery < 2) {
 948                 level_ac_battery = 2 - level_ac_battery;
 949                 br->flags._BCL_no_ac_battery_levels = 1;
 950                 for (i = (count - 1 + level_ac_battery); i >= 2; i--)
 951                         br->levels[i] = br->levels[i - level_ac_battery];
 952                 count += level_ac_battery;
 953         } else if (level_ac_battery > 2)
 954                 ACPI_ERROR((AE_INFO, "Too many duplicates in _BCL package"));
 955
 956         /* Check if the _BCL package is in a reversed order */
 957         if (max_level == br->levels[2]) {
 958                 br->flags._BCL_reversed = 1;
 959                 sort(&br->levels[2], count - 2, sizeof(br->levels[2]),
 960                         acpi_video_cmp_level, NULL);
 961         } else if (max_level != br->levels[count - 1])
 962                 ACPI_ERROR((AE_INFO,
 963                             "Found unordered _BCL package"));
 964
 965         br->count = count;
 966         device->brightness = br;
 967
 968         /* _BQC uses INDEX while _BCL uses VALUE in some laptops */
 969         br->curr = level = max_level;
 970
 971         if (!device->cap._BQC)
 972                 goto set_level;
 973
 974         result = acpi_video_device_lcd_get_level_current(device,
 975                                                          &level_old, true);
 976         if (result)
 977                 goto out_free_levels;
 978
 979         result = acpi_video_bqc_quirk(device, max_level, level_old);
 980         if (result)
 981                 goto out_free_levels;
 982         /*
 983          * cap._BQC may get cleared due to _BQC is found to be broken
 984          * in acpi_video_bqc_quirk, so check again here.
 985          */
 986         if (!device->cap._BQC)
 987                 goto set_level;
 988
 989         level = acpi_video_bqc_value_to_level(device, level_old);
 990         /*
 991          * On some buggy laptops, _BQC returns an uninitialized
 992          * value when invoked for the first time, i.e.
 993          * level_old is invalid (no matter whether it's a level
 994          * or an index). Set the backlight to max_level in this case.
 995          */
 996         for (i = 2; i < br->count; i++)
 997                 if (level == br->levels[i])
 998                         break;
 999         if (i == br->count || !level)
1000                 level = max_level;
1001
1002 set_level:
1003         result = acpi_video_device_lcd_set_level(device, level);
1004         if (result)
1005                 goto out_free_levels;
1006
1007         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1008                           "found %d brightness levels\n", count - 2));
1009         kfree(obj);
1010         return result;
1011
1012 out_free_levels:
1013         kfree(br->levels);
1014 out_free:
1015         kfree(br);
1016 out:
1017         device->brightness = NULL;
1018         kfree(obj);
1019         return result;
1020 }
1021
1022 /*
1023  *  Arg:
1024  *      device  : video output device (LCD, CRT, ..)
1025  *
1026  *  Return Value:
1027  *      None
1028  *
1029  *  Find out all required AML methods defined under the output
1030  *  device.
1031  */
1032
1033 static void acpi_video_device_find_cap(struct acpi_video_device *device)
1034 {
1035         if (acpi_has_method(device->dev->handle, "_ADR"))
1036                 device->cap._ADR = 1;
1037         if (acpi_has_method(device->dev->handle, "_BCL"))
1038                 device->cap._BCL = 1;
1039         if (acpi_has_method(device->dev->handle, "_BCM"))
1040                 device->cap._BCM = 1;
1041         if (acpi_has_method(device->dev->handle, "_BQC")) {
1042                 device->cap._BQC = 1;
1043         } else if (acpi_has_method(device->dev->handle, "_BCQ")) {
1044                 printk(KERN_WARNING FW_BUG "_BCQ is used instead of _BQC\n");
1045                 device->cap._BCQ = 1;
1046         }
1047
1048         if (acpi_has_method(device->dev->handle, "_DDC"))
1049                 device->cap._DDC = 1;
1050 }
1051
1052 /*
1053  *  Arg:
1054  *      device  : video output device (VGA)
1055  *
1056  *  Return Value:
1057  *      None
1058  *
1059  *  Find out all required AML methods defined under the video bus device.
1060  */
1061
1062 static void acpi_video_bus_find_cap(struct acpi_video_bus *video)
1063 {
1064         if (acpi_has_method(video->device->handle, "_DOS"))
1065                 video->cap._DOS = 1;
1066         if (acpi_has_method(video->device->handle, "_DOD"))
1067                 video->cap._DOD = 1;
1068         if (acpi_has_method(video->device->handle, "_ROM"))
1069                 video->cap._ROM = 1;
1070         if (acpi_has_method(video->device->handle, "_GPD"))
1071                 video->cap._GPD = 1;
1072         if (acpi_has_method(video->device->handle, "_SPD"))
1073                 video->cap._SPD = 1;
1074         if (acpi_has_method(video->device->handle, "_VPO"))
1075                 video->cap._VPO = 1;
1076 }
1077
1078 /*
1079  * Check whether the video bus device has required AML method to
1080  * support the desired features
1081  */
1082
1083 static int acpi_video_bus_check(struct acpi_video_bus *video)
1084 {
1085         acpi_status status = -ENOENT;
1086         struct pci_dev *dev;
1087
1088         if (!video)
1089                 return -EINVAL;
1090
1091         dev = acpi_get_pci_dev(video->device->handle);
1092         if (!dev)
1093                 return -ENODEV;
1094         pci_dev_put(dev);
1095
1096         /*
1097          * Since there is no HID, CID and so on for VGA driver, we have
1098          * to check well known required nodes.
1099          */
1100
1101         /* Does this device support video switching? */
1102         if (video->cap._DOS || video->cap._DOD) {
1103                 if (!video->cap._DOS) {
1104                         printk(KERN_WARNING FW_BUG
1105                                 "ACPI(%s) defines _DOD but not _DOS\n",
1106                                 acpi_device_bid(video->device));
1107                 }
1108                 video->flags.multihead = 1;
1109                 status = 0;
1110         }
1111
1112         /* Does this device support retrieving a video ROM? */
1113         if (video->cap._ROM) {
1114                 video->flags.rom = 1;
1115                 status = 0;
1116         }
1117
1118         /* Does this device support configuring which video device to POST? */
1119         if (video->cap._GPD && video->cap._SPD && video->cap._VPO) {
1120                 video->flags.post = 1;
1121                 status = 0;
1122         }
1123
1124         return status;
1125 }
1126
1127 /*
1128  * --------------------------------------------------------------------------
1129  *                               Driver Interface
1130  * --------------------------------------------------------------------------
1131  */
1132
1133 /* device interface */
1134 static struct acpi_video_device_attrib *
1135 acpi_video_get_device_attr(struct acpi_video_bus *video, unsigned long device_id)
1136 {
1137         struct acpi_video_enumerated_device *ids;
1138         int i;
1139
1140         for (i = 0; i < video->attached_count; i++) {
1141                 ids = &video->attached_array[i];
1142                 if ((ids->value.int_val & 0xffff) == device_id)
1143                         return &ids->value.attrib;
1144         }
1145
1146         return NULL;
1147 }
1148
1149 static int
1150 acpi_video_get_device_type(struct acpi_video_bus *video,
1151                            unsigned long device_id)
1152 {
1153         struct acpi_video_enumerated_device *ids;
1154         int i;
1155
1156         for (i = 0; i < video->attached_count; i++) {
1157                 ids = &video->attached_array[i];
1158                 if ((ids->value.int_val & 0xffff) == device_id)
1159                         return ids->value.int_val;
1160         }
1161
1162         return 0;
1163 }
1164
1165 static int
1166 acpi_video_bus_get_one_device(struct acpi_device *device,
1167                               struct acpi_video_bus *video)
1168 {
1169         unsigned long long device_id;
1170         int status, device_type;
1171         struct acpi_video_device *data;
1172         struct acpi_video_device_attrib *attribute;
1173
1174         status =
1175             acpi_evaluate_integer(device->handle, "_ADR", NULL, &device_id);
1176         /* Some device omits _ADR, we skip them instead of fail */
1177         if (ACPI_FAILURE(status))
1178                 return 0;
1179
1180         data = kzalloc(sizeof(struct acpi_video_device), GFP_KERNEL);
1181         if (!data)
1182                 return -ENOMEM;
1183
1184         strcpy(acpi_device_name(device), ACPI_VIDEO_DEVICE_NAME);
1185         strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
1186         device->driver_data = data;
1187
1188         data->device_id = device_id;
1189         data->video = video;
1190         data->dev = device;
1191
1192         attribute = acpi_video_get_device_attr(video, device_id);
1193
1194         if (attribute && attribute->device_id_scheme) {
1195                 switch (attribute->display_type) {
1196                 case ACPI_VIDEO_DISPLAY_CRT:
1197                         data->flags.crt = 1;
1198                         break;
1199                 case ACPI_VIDEO_DISPLAY_TV:
1200                         data->flags.tvout = 1;
1201                         break;
1202                 case ACPI_VIDEO_DISPLAY_DVI:
1203                         data->flags.dvi = 1;
1204                         break;
1205                 case ACPI_VIDEO_DISPLAY_LCD:
1206                         data->flags.lcd = 1;
1207                         break;
1208                 default:
1209                         data->flags.unknown = 1;
1210                         break;
1211                 }
1212                 if (attribute->bios_can_detect)
1213                         data->flags.bios = 1;
1214         } else {
1215                 /* Check for legacy IDs */
1216                 device_type = acpi_video_get_device_type(video, device_id);
1217                 /* Ignore bits 16 and 18-20 */
1218                 switch (device_type & 0xffe2ffff) {
1219                 case ACPI_VIDEO_DISPLAY_LEGACY_MONITOR:
1220                         data->flags.crt = 1;
1221                         break;
1222                 case ACPI_VIDEO_DISPLAY_LEGACY_PANEL:
1223                         data->flags.lcd = 1;
1224                         break;
1225                 case ACPI_VIDEO_DISPLAY_LEGACY_TV:
1226                         data->flags.tvout = 1;
1227                         break;
1228                 default:
1229                         data->flags.unknown = 1;
1230                 }
1231         }
1232
1233         acpi_video_device_bind(video, data);
1234         acpi_video_device_find_cap(data);
1235
1236         mutex_lock(&video->device_list_lock);
1237         list_add_tail(&data->entry, &video->video_device_list);
1238         mutex_unlock(&video->device_list_lock);
1239
1240         return status;
1241 }
1242
1243 /*
1244  *  Arg:
1245  *      video   : video bus device
1246  *
1247  *  Return:
1248  *      none
1249  *
1250  *  Enumerate the video device list of the video bus,
1251  *  bind the ids with the corresponding video devices
1252  *  under the video bus.
1253  */
1254
1255 static void acpi_video_device_rebind(struct acpi_video_bus *video)
1256 {
1257         struct acpi_video_device *dev;
1258
1259         mutex_lock(&video->device_list_lock);
1260
1261         list_for_each_entry(dev, &video->video_device_list, entry)
1262                 acpi_video_device_bind(video, dev);
1263
1264         mutex_unlock(&video->device_list_lock);
1265 }
1266
1267 /*
1268  *  Arg:
1269  *      video   : video bus device
1270  *      device  : video output device under the video
1271  *              bus
1272  *
1273  *  Return:
1274  *      none
1275  *
1276  *  Bind the ids with the corresponding video devices
1277  *  under the video bus.
1278  */
1279
1280 static void
1281 acpi_video_device_bind(struct acpi_video_bus *video,
1282                        struct acpi_video_device *device)
1283 {
1284         struct acpi_video_enumerated_device *ids;
1285         int i;
1286
1287         for (i = 0; i < video->attached_count; i++) {
1288                 ids = &video->attached_array[i];
1289                 if (device->device_id == (ids->value.int_val & 0xffff)) {
1290                         ids->bind_info = device;
1291                         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "device_bind %d\n", i));
1292                 }
1293         }
1294 }
1295
1296 /*
1297  *  Arg:
1298  *      video   : video bus device
1299  *
1300  *  Return:
1301  *      < 0     : error
1302  *
1303  *  Call _DOD to enumerate all devices attached to display adapter
1304  *
1305  */
1306
1307 static int acpi_video_device_enumerate(struct acpi_video_bus *video)
1308 {
1309         int status;
1310         int count;
1311         int i;
1312         struct acpi_video_enumerated_device *active_list;
1313         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1314         union acpi_object *dod = NULL;
1315         union acpi_object *obj;
1316
1317         status = acpi_evaluate_object(video->device->handle, "_DOD", NULL, &buffer);
1318         if (!ACPI_SUCCESS(status)) {
1319                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _DOD"));
1320                 return status;
1321         }
1322
1323         dod = buffer.pointer;
1324         if (!dod || (dod->type != ACPI_TYPE_PACKAGE)) {
1325                 ACPI_EXCEPTION((AE_INFO, status, "Invalid _DOD data"));
1326                 status = -EFAULT;
1327                 goto out;
1328         }
1329
1330         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d video heads in _DOD\n",
1331                           dod->package.count));
1332
1333         active_list = kcalloc(1 + dod->package.count,
1334                               sizeof(struct acpi_video_enumerated_device),
1335                               GFP_KERNEL);
1336         if (!active_list) {
1337                 status = -ENOMEM;
1338                 goto out;
1339         }
1340
1341         count = 0;
1342         for (i = 0; i < dod->package.count; i++) {
1343                 obj = &dod->package.elements[i];
1344
1345                 if (obj->type != ACPI_TYPE_INTEGER) {
1346                         printk(KERN_ERR PREFIX
1347                                 "Invalid _DOD data in element %d\n", i);
1348                         continue;
1349                 }
1350
1351                 active_list[count].value.int_val = obj->integer.value;
1352                 active_list[count].bind_info = NULL;
1353                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "dod element[%d] = %d\n", i,
1354                                   (int)obj->integer.value));
1355                 count++;
1356         }
1357
1358         kfree(video->attached_array);
1359
1360         video->attached_array = active_list;
1361         video->attached_count = count;
1362
1363 out:
1364         kfree(buffer.pointer);
1365         return status;
1366 }
1367
1368 static int
1369 acpi_video_get_next_level(struct acpi_video_device *device,
1370                           u32 level_current, u32 event)
1371 {
1372         int min, max, min_above, max_below, i, l, delta = 255;
1373         max = max_below = 0;
1374         min = min_above = 255;
1375         /* Find closest level to level_current */
1376         for (i = 2; i < device->brightness->count; i++) {
1377                 l = device->brightness->levels[i];
1378                 if (abs(l - level_current) < abs(delta)) {
1379                         delta = l - level_current;
1380                         if (!delta)
1381                                 break;
1382                 }
1383         }
1384         /* Ajust level_current to closest available level */
1385         level_current += delta;
1386         for (i = 2; i < device->brightness->count; i++) {
1387                 l = device->brightness->levels[i];
1388                 if (l < min)
1389                         min = l;
1390                 if (l > max)
1391                         max = l;
1392                 if (l < min_above && l > level_current)
1393                         min_above = l;
1394                 if (l > max_below && l < level_current)
1395                         max_below = l;
1396         }
1397
1398         switch (event) {
1399         case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:
1400                 return (level_current < max) ? min_above : min;
1401         case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:
1402                 return (level_current < max) ? min_above : max;
1403         case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:
1404                 return (level_current > min) ? max_below : min;
1405         case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS:
1406         case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:
1407                 return 0;
1408         default:
1409                 return level_current;
1410         }
1411 }
1412
1413 static int
1414 acpi_video_switch_brightness(struct acpi_video_device *device, int event)
1415 {
1416         unsigned long long level_current, level_next;
1417         int result = -EINVAL;
1418
1419         /* no warning message if acpi_backlight=vendor or a quirk is used */
1420         if (!acpi_video_verify_backlight_support())
1421                 return 0;
1422
1423         if (!device->brightness)
1424                 goto out;
1425
1426         result = acpi_video_device_lcd_get_level_current(device,
1427                                                          &level_current,
1428                                                          false);
1429         if (result)
1430                 goto out;
1431
1432         level_next = acpi_video_get_next_level(device, level_current, event);
1433
1434         result = acpi_video_device_lcd_set_level(device, level_next);
1435
1436         if (!result)
1437                 backlight_force_update(device->backlight,
1438                                        BACKLIGHT_UPDATE_HOTKEY);
1439
1440 out:
1441         if (result)
1442                 printk(KERN_ERR PREFIX "Failed to switch the brightness\n");
1443
1444         return result;
1445 }
1446
1447 int acpi_video_get_edid(struct acpi_device *device, int type, int device_id,
1448                         void **edid)
1449 {
1450         struct acpi_video_bus *video;
1451         struct acpi_video_device *video_device;
1452         union acpi_object *buffer = NULL;
1453         acpi_status status;
1454         int i, length;
1455
1456         if (!device || !acpi_driver_data(device))
1457                 return -EINVAL;
1458
1459         video = acpi_driver_data(device);
1460
1461         for (i = 0; i < video->attached_count; i++) {
1462                 video_device = video->attached_array[i].bind_info;
1463                 length = 256;
1464
1465                 if (!video_device)
1466                         continue;
1467
1468                 if (!video_device->cap._DDC)
1469                         continue;
1470
1471                 if (type) {
1472                         switch (type) {
1473                         case ACPI_VIDEO_DISPLAY_CRT:
1474                                 if (!video_device->flags.crt)
1475                                         continue;
1476                                 break;
1477                         case ACPI_VIDEO_DISPLAY_TV:
1478                                 if (!video_device->flags.tvout)
1479                                         continue;
1480                                 break;
1481                         case ACPI_VIDEO_DISPLAY_DVI:
1482                                 if (!video_device->flags.dvi)
1483                                         continue;
1484                                 break;
1485                         case ACPI_VIDEO_DISPLAY_LCD:
1486                                 if (!video_device->flags.lcd)
1487                                         continue;
1488                                 break;
1489                         }
1490                 } else if (video_device->device_id != device_id) {
1491                         continue;
1492                 }
1493
1494                 status = acpi_video_device_EDID(video_device, &buffer, length);
1495
1496                 if (ACPI_FAILURE(status) || !buffer ||
1497                     buffer->type != ACPI_TYPE_BUFFER) {
1498                         length = 128;
1499                         status = acpi_video_device_EDID(video_device, &buffer,
1500                                                         length);
1501                         if (ACPI_FAILURE(status) || !buffer ||
1502                             buffer->type != ACPI_TYPE_BUFFER) {
1503                                 continue;
1504                         }
1505                 }
1506
1507                 *edid = buffer->buffer.pointer;
1508                 return length;
1509         }
1510
1511         return -ENODEV;
1512 }
1513 EXPORT_SYMBOL(acpi_video_get_edid);
1514
1515 static int
1516 acpi_video_bus_get_devices(struct acpi_video_bus *video,
1517                            struct acpi_device *device)
1518 {
1519         int status = 0;
1520         struct acpi_device *dev;
1521
1522         /*
1523          * There are systems where video module known to work fine regardless
1524          * of broken _DOD and ignoring returned value here doesn't cause
1525          * any issues later.
1526          */
1527         acpi_video_device_enumerate(video);
1528
1529         list_for_each_entry(dev, &device->children, node) {
1530
1531                 status = acpi_video_bus_get_one_device(dev, video);
1532                 if (status) {
1533                         dev_err(&dev->dev, "Can't attach device\n");
1534                         break;
1535                 }
1536         }
1537         return status;
1538 }
1539
1540 /* acpi_video interface */
1541
1542 /*
1543  * Win8 requires setting bit2 of _DOS to let firmware know it shouldn't
1544  * preform any automatic brightness change on receiving a notification.
1545  */
1546 static int acpi_video_bus_start_devices(struct acpi_video_bus *video)
1547 {
1548         return acpi_video_bus_DOS(video, 0,
1549                                   acpi_osi_is_win8() ? 1 : 0);
1550 }
1551
1552 static int acpi_video_bus_stop_devices(struct acpi_video_bus *video)
1553 {
1554         return acpi_video_bus_DOS(video, 0,
1555                                   acpi_osi_is_win8() ? 0 : 1);
1556 }
1557
1558 static void acpi_video_bus_notify(struct acpi_device *device, u32 event)
1559 {
1560         struct acpi_video_bus *video = acpi_driver_data(device);
1561         struct input_dev *input;
1562         int keycode = 0;
1563
1564         if (!video || !video->input)
1565                 return;
1566
1567         input = video->input;
1568
1569         switch (event) {
1570         case ACPI_VIDEO_NOTIFY_SWITCH:  /* User requested a switch,
1571                                          * most likely via hotkey. */
1572                 keycode = KEY_SWITCHVIDEOMODE;
1573                 break;
1574
1575         case ACPI_VIDEO_NOTIFY_PROBE:   /* User plugged in or removed a video
1576                                          * connector. */
1577                 acpi_video_device_enumerate(video);
1578                 acpi_video_device_rebind(video);
1579                 keycode = KEY_SWITCHVIDEOMODE;
1580                 break;
1581
1582         case ACPI_VIDEO_NOTIFY_CYCLE:   /* Cycle Display output hotkey pressed. */
1583                 keycode = KEY_SWITCHVIDEOMODE;
1584                 break;
1585         case ACPI_VIDEO_NOTIFY_NEXT_OUTPUT:     /* Next Display output hotkey pressed. */
1586                 keycode = KEY_VIDEO_NEXT;
1587                 break;
1588         case ACPI_VIDEO_NOTIFY_PREV_OUTPUT:     /* previous Display output hotkey pressed. */
1589                 keycode = KEY_VIDEO_PREV;
1590                 break;
1591
1592         default:
1593                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1594                                   "Unsupported event [0x%x]\n", event));
1595                 break;
1596         }
1597
1598         if (acpi_notifier_call_chain(device, event, 0))
1599                 /* Something vetoed the keypress. */
1600                 keycode = 0;
1601
1602         if (keycode) {
1603                 input_report_key(input, keycode, 1);
1604                 input_sync(input);
1605                 input_report_key(input, keycode, 0);
1606                 input_sync(input);
1607         }
1608
1609         return;
1610 }
1611
1612 static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data)
1613 {
1614         struct acpi_video_device *video_device = data;
1615         struct acpi_device *device = NULL;
1616         struct acpi_video_bus *bus;
1617         struct input_dev *input;
1618         int keycode = 0;
1619
1620         if (!video_device)
1621                 return;
1622
1623         device = video_device->dev;
1624         bus = video_device->video;
1625         input = bus->input;
1626
1627         switch (event) {
1628         case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:        /* Cycle brightness */
1629                 if (brightness_switch_enabled)
1630                         acpi_video_switch_brightness(video_device, event);
1631                 keycode = KEY_BRIGHTNESS_CYCLE;
1632                 break;
1633         case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:  /* Increase brightness */
1634                 if (brightness_switch_enabled)
1635                         acpi_video_switch_brightness(video_device, event);
1636                 keycode = KEY_BRIGHTNESSUP;
1637                 break;
1638         case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:  /* Decrease brightness */
1639                 if (brightness_switch_enabled)
1640                         acpi_video_switch_brightness(video_device, event);
1641                 keycode = KEY_BRIGHTNESSDOWN;
1642                 break;
1643         case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS: /* zero brightness */
1644                 if (brightness_switch_enabled)
1645                         acpi_video_switch_brightness(video_device, event);
1646                 keycode = KEY_BRIGHTNESS_ZERO;
1647                 break;
1648         case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:     /* display device off */
1649                 if (brightness_switch_enabled)
1650                         acpi_video_switch_brightness(video_device, event);
1651                 keycode = KEY_DISPLAY_OFF;
1652                 break;
1653         default:
1654                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1655                                   "Unsupported event [0x%x]\n", event));
1656                 break;
1657         }
1658
1659         acpi_notifier_call_chain(device, event, 0);
1660
1661         if (keycode) {
1662                 input_report_key(input, keycode, 1);
1663                 input_sync(input);
1664                 input_report_key(input, keycode, 0);
1665                 input_sync(input);
1666         }
1667
1668         return;
1669 }
1670
1671 static int acpi_video_resume(struct notifier_block *nb,
1672                                 unsigned long val, void *ign)
1673 {
1674         struct acpi_video_bus *video;
1675         struct acpi_video_device *video_device;
1676         int i;
1677
1678         switch (val) {
1679         case PM_HIBERNATION_PREPARE:
1680         case PM_SUSPEND_PREPARE:
1681         case PM_RESTORE_PREPARE:
1682                 return NOTIFY_DONE;
1683         }
1684
1685         video = container_of(nb, struct acpi_video_bus, pm_nb);
1686
1687         dev_info(&video->device->dev, "Restoring backlight state\n");
1688
1689         for (i = 0; i < video->attached_count; i++) {
1690                 video_device = video->attached_array[i].bind_info;
1691                 if (video_device && video_device->backlight)
1692                         acpi_video_set_brightness(video_device->backlight);
1693         }
1694
1695         return NOTIFY_OK;
1696 }
1697
1698 static acpi_status
1699 acpi_video_bus_match(acpi_handle handle, u32 level, void *context,
1700                         void **return_value)
1701 {
1702         struct acpi_device *device = context;
1703         struct acpi_device *sibling;
1704         int result;
1705
1706         if (handle == device->handle)
1707                 return AE_CTRL_TERMINATE;
1708
1709         result = acpi_bus_get_device(handle, &sibling);
1710         if (result)
1711                 return AE_OK;
1712
1713         if (!strcmp(acpi_device_name(sibling), ACPI_VIDEO_BUS_NAME))
1714                         return AE_ALREADY_EXISTS;
1715
1716         return AE_OK;
1717 }
1718
1719 static void acpi_video_dev_register_backlight(struct acpi_video_device *device)
1720 {
1721         struct backlight_properties props;
1722         struct pci_dev *pdev;
1723         acpi_handle acpi_parent;
1724         struct device *parent = NULL;
1725         int result;
1726         static int count;
1727         char *name;
1728
1729         result = acpi_video_init_brightness(device);
1730         if (result)
1731                 return;
1732         name = kasprintf(GFP_KERNEL, "acpi_video%d", count);
1733         if (!name)
1734                 return;
1735         count++;
1736
1737         acpi_get_parent(device->dev->handle, &acpi_parent);
1738
1739         pdev = acpi_get_pci_dev(acpi_parent);
1740         if (pdev) {
1741                 parent = &pdev->dev;
1742                 pci_dev_put(pdev);
1743         }
1744
1745         memset(&props, 0, sizeof(struct backlight_properties));
1746         props.type = BACKLIGHT_FIRMWARE;
1747         props.max_brightness = device->brightness->count - 3;
1748         device->backlight = backlight_device_register(name,
1749                                                       parent,
1750                                                       device,
1751                                                       &acpi_backlight_ops,
1752                                                       &props);
1753         kfree(name);
1754         if (IS_ERR(device->backlight))
1755                 return;
1756
1757         /*
1758          * Save current brightness level in case we have to restore it
1759          * before acpi_video_device_lcd_set_level() is called next time.
1760          */
1761         device->backlight->props.brightness =
1762                         acpi_video_get_brightness(device->backlight);
1763
1764         device->cooling_dev = thermal_cooling_device_register("LCD",
1765                                 device->dev, &video_cooling_ops);
1766         if (IS_ERR(device->cooling_dev)) {
1767                 /*
1768                  * Set cooling_dev to NULL so we don't crash trying to free it.
1769                  * Also, why the hell we are returning early and not attempt to
1770                  * register video output if cooling device registration failed?
1771                  * -- dtor
1772                  */
1773                 device->cooling_dev = NULL;
1774                 return;
1775         }
1776
1777         dev_info(&device->dev->dev, "registered as cooling_device%d\n",
1778                  device->cooling_dev->id);
1779         result = sysfs_create_link(&device->dev->dev.kobj,
1780                         &device->cooling_dev->device.kobj,
1781                         "thermal_cooling");
1782         if (result)
1783                 printk(KERN_ERR PREFIX "Create sysfs link\n");
1784         result = sysfs_create_link(&device->cooling_dev->device.kobj,
1785                         &device->dev->dev.kobj, "device");
1786         if (result)
1787                 printk(KERN_ERR PREFIX "Create sysfs link\n");
1788 }
1789
1790 static int acpi_video_bus_register_backlight(struct acpi_video_bus *video)
1791 {
1792         struct acpi_video_device *dev;
1793
1794         if (video->backlight_registered)
1795                 return 0;
1796
1797         if (!acpi_video_verify_backlight_support())
1798                 return 0;
1799
1800         mutex_lock(&video->device_list_lock);
1801         list_for_each_entry(dev, &video->video_device_list, entry)
1802                 acpi_video_dev_register_backlight(dev);
1803         mutex_unlock(&video->device_list_lock);
1804
1805         video->backlight_registered = true;
1806
1807         video->pm_nb.notifier_call = acpi_video_resume;
1808         video->pm_nb.priority = 0;
1809         return register_pm_notifier(&video->pm_nb);
1810 }
1811
1812 static void acpi_video_dev_unregister_backlight(struct acpi_video_device *device)
1813 {
1814         if (device->backlight) {
1815                 backlight_device_unregister(device->backlight);
1816                 device->backlight = NULL;
1817         }
1818         if (device->brightness) {
1819                 kfree(device->brightness->levels);
1820                 kfree(device->brightness);
1821                 device->brightness = NULL;
1822         }
1823         if (device->cooling_dev) {
1824                 sysfs_remove_link(&device->dev->dev.kobj, "thermal_cooling");
1825                 sysfs_remove_link(&device->cooling_dev->device.kobj, "device");
1826                 thermal_cooling_device_unregister(device->cooling_dev);
1827                 device->cooling_dev = NULL;
1828         }
1829 }
1830
1831 static int acpi_video_bus_unregister_backlight(struct acpi_video_bus *video)
1832 {
1833         struct acpi_video_device *dev;
1834         int error;
1835
1836         if (!video->backlight_registered)
1837                 return 0;
1838
1839         error = unregister_pm_notifier(&video->pm_nb);
1840
1841         mutex_lock(&video->device_list_lock);
1842         list_for_each_entry(dev, &video->video_device_list, entry)
1843                 acpi_video_dev_unregister_backlight(dev);
1844         mutex_unlock(&video->device_list_lock);
1845
1846         video->backlight_registered = false;
1847
1848         return error;
1849 }
1850
1851 static void acpi_video_dev_add_notify_handler(struct acpi_video_device *device)
1852 {
1853         acpi_status status;
1854         struct acpi_device *adev = device->dev;
1855
1856         status = acpi_install_notify_handler(adev->handle, ACPI_DEVICE_NOTIFY,
1857                                              acpi_video_device_notify, device);
1858         if (ACPI_FAILURE(status))
1859                 dev_err(&adev->dev, "Error installing notify handler\n");
1860         else
1861                 device->flags.notify = 1;
1862 }
1863
1864 static int acpi_video_bus_add_notify_handler(struct acpi_video_bus *video)
1865 {
1866         struct input_dev *input;
1867         struct acpi_video_device *dev;
1868         int error;
1869
1870         video->input = input = input_allocate_device();
1871         if (!input) {
1872                 error = -ENOMEM;
1873                 goto out;
1874         }
1875
1876         error = acpi_video_bus_start_devices(video);
1877         if (error)
1878                 goto err_free_input;
1879
1880         snprintf(video->phys, sizeof(video->phys),
1881                         "%s/video/input0", acpi_device_hid(video->device));
1882
1883         input->name = acpi_device_name(video->device);
1884         input->phys = video->phys;
1885         input->id.bustype = BUS_HOST;
1886         input->id.product = 0x06;
1887         input->dev.parent = &video->device->dev;
1888         input->evbit[0] = BIT(EV_KEY);
1889         set_bit(KEY_SWITCHVIDEOMODE, input->keybit);
1890         set_bit(KEY_VIDEO_NEXT, input->keybit);
1891         set_bit(KEY_VIDEO_PREV, input->keybit);
1892         set_bit(KEY_BRIGHTNESS_CYCLE, input->keybit);
1893         set_bit(KEY_BRIGHTNESSUP, input->keybit);
1894         set_bit(KEY_BRIGHTNESSDOWN, input->keybit);
1895         set_bit(KEY_BRIGHTNESS_ZERO, input->keybit);
1896         set_bit(KEY_DISPLAY_OFF, input->keybit);
1897
1898         error = input_register_device(input);
1899         if (error)
1900                 goto err_stop_dev;
1901
1902         mutex_lock(&video->device_list_lock);
1903         list_for_each_entry(dev, &video->video_device_list, entry)
1904                 acpi_video_dev_add_notify_handler(dev);
1905         mutex_unlock(&video->device_list_lock);
1906
1907         return 0;
1908
1909 err_stop_dev:
1910         acpi_video_bus_stop_devices(video);
1911 err_free_input:
1912         input_free_device(input);
1913         video->input = NULL;
1914 out:
1915         return error;
1916 }
1917
1918 static void acpi_video_dev_remove_notify_handler(struct acpi_video_device *dev)
1919 {
1920         if (dev->flags.notify) {
1921                 acpi_remove_notify_handler(dev->dev->handle, ACPI_DEVICE_NOTIFY,
1922                                            acpi_video_device_notify);
1923                 dev->flags.notify = 0;
1924         }
1925 }
1926
1927 static void acpi_video_bus_remove_notify_handler(struct acpi_video_bus *video)
1928 {
1929         struct acpi_video_device *dev;
1930
1931         mutex_lock(&video->device_list_lock);
1932         list_for_each_entry(dev, &video->video_device_list, entry)
1933                 acpi_video_dev_remove_notify_handler(dev);
1934         mutex_unlock(&video->device_list_lock);
1935
1936         acpi_video_bus_stop_devices(video);
1937         input_unregister_device(video->input);
1938         video->input = NULL;
1939 }
1940
1941 static int acpi_video_backlight_notify(struct notifier_block *nb,
1942                                         unsigned long val, void *bd)
1943 {
1944         struct backlight_device *backlight = bd;
1945         struct acpi_video_bus *video;
1946
1947         /* acpi_video_verify_backlight_support only cares about raw devices */
1948         if (backlight->props.type != BACKLIGHT_RAW)
1949                 return NOTIFY_DONE;
1950
1951         video = container_of(nb, struct acpi_video_bus, backlight_nb);
1952
1953         switch (val) {
1954         case BACKLIGHT_REGISTERED:
1955                 if (!acpi_video_verify_backlight_support())
1956                         acpi_video_bus_unregister_backlight(video);
1957                 break;
1958         case BACKLIGHT_UNREGISTERED:
1959                 acpi_video_bus_register_backlight(video);
1960                 break;
1961         }
1962
1963         return NOTIFY_OK;
1964 }
1965
1966 static int acpi_video_bus_add_backlight_notify_handler(
1967                                                 struct acpi_video_bus *video)
1968 {
1969         int error;
1970
1971         video->backlight_nb.notifier_call = acpi_video_backlight_notify;
1972         video->backlight_nb.priority = 0;
1973         error = backlight_register_notifier(&video->backlight_nb);
1974         if (error == 0)
1975                 video->backlight_notifier_registered = true;
1976
1977         return error;
1978 }
1979
1980 static int acpi_video_bus_remove_backlight_notify_handler(
1981                                                 struct acpi_video_bus *video)
1982 {
1983         if (!video->backlight_notifier_registered)
1984                 return 0;
1985
1986         video->backlight_notifier_registered = false;
1987
1988         return backlight_unregister_notifier(&video->backlight_nb);
1989 }
1990
1991 static int acpi_video_bus_put_devices(struct acpi_video_bus *video)
1992 {
1993         struct acpi_video_device *dev, *next;
1994
1995         mutex_lock(&video->device_list_lock);
1996         list_for_each_entry_safe(dev, next, &video->video_device_list, entry) {
1997                 list_del(&dev->entry);
1998                 kfree(dev);
1999         }
2000         mutex_unlock(&video->device_list_lock);
2001
2002         return 0;
2003 }
2004
2005 static int instance;
2006
2007 static int acpi_video_bus_add(struct acpi_device *device)
2008 {
2009         struct acpi_video_bus *video;
2010         int error;
2011         acpi_status status;
2012
2013         status = acpi_walk_namespace(ACPI_TYPE_DEVICE,
2014                                 device->parent->handle, 1,
2015                                 acpi_video_bus_match, NULL,
2016                                 device, NULL);
2017         if (status == AE_ALREADY_EXISTS) {
2018                 printk(KERN_WARNING FW_BUG
2019                         "Duplicate ACPI video bus devices for the"
2020                         " same VGA controller, please try module "
2021                         "parameter \"video.allow_duplicates=1\""
2022                         "if the current driver doesn't work.\n");
2023                 if (!allow_duplicates)
2024                         return -ENODEV;
2025         }
2026
2027         video = kzalloc(sizeof(struct acpi_video_bus), GFP_KERNEL);
2028         if (!video)
2029                 return -ENOMEM;
2030
2031         /* a hack to fix the duplicate name "VID" problem on T61 */
2032         if (!strcmp(device->pnp.bus_id, "VID")) {
2033                 if (instance)
2034                         device->pnp.bus_id[3] = '0' + instance;
2035                 instance++;
2036         }
2037         /* a hack to fix the duplicate name "VGA" problem on Pa 3553 */
2038         if (!strcmp(device->pnp.bus_id, "VGA")) {
2039                 if (instance)
2040                         device->pnp.bus_id[3] = '0' + instance;
2041                 instance++;
2042         }
2043
2044         video->device = device;
2045         strcpy(acpi_device_name(device), ACPI_VIDEO_BUS_NAME);
2046         strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
2047         device->driver_data = video;
2048
2049         acpi_video_bus_find_cap(video);
2050         error = acpi_video_bus_check(video);
2051         if (error)
2052                 goto err_free_video;
2053
2054         mutex_init(&video->device_list_lock);
2055         INIT_LIST_HEAD(&video->video_device_list);
2056
2057         error = acpi_video_bus_get_devices(video, device);
2058         if (error)
2059                 goto err_put_video;
2060
2061         printk(KERN_INFO PREFIX "%s [%s] (multi-head: %s  rom: %s  post: %s)\n",
2062                ACPI_VIDEO_DEVICE_NAME, acpi_device_bid(device),
2063                video->flags.multihead ? "yes" : "no",
2064                video->flags.rom ? "yes" : "no",
2065                video->flags.post ? "yes" : "no");
2066         mutex_lock(&video_list_lock);
2067         list_add_tail(&video->entry, &video_bus_head);
2068         mutex_unlock(&video_list_lock);
2069
2070         acpi_video_bus_register_backlight(video);
2071         acpi_video_bus_add_notify_handler(video);
2072         acpi_video_bus_add_backlight_notify_handler(video);
2073
2074         return 0;
2075
2076 err_put_video:
2077         acpi_video_bus_put_devices(video);
2078         kfree(video->attached_array);
2079 err_free_video:
2080         kfree(video);
2081         device->driver_data = NULL;
2082
2083         return error;
2084 }
2085
2086 static int acpi_video_bus_remove(struct acpi_device *device)
2087 {
2088         struct acpi_video_bus *video = NULL;
2089
2090
2091         if (!device || !acpi_driver_data(device))
2092                 return -EINVAL;
2093
2094         video = acpi_driver_data(device);
2095
2096         acpi_video_bus_remove_backlight_notify_handler(video);
2097         acpi_video_bus_remove_notify_handler(video);
2098         acpi_video_bus_unregister_backlight(video);
2099         acpi_video_bus_put_devices(video);
2100
2101         mutex_lock(&video_list_lock);
2102         list_del(&video->entry);
2103         mutex_unlock(&video_list_lock);
2104
2105         kfree(video->attached_array);
2106         kfree(video);
2107
2108         return 0;
2109 }
2110
2111 static int __init is_i740(struct pci_dev *dev)
2112 {
2113         if (dev->device == 0x00D1)
2114                 return 1;
2115         if (dev->device == 0x7000)
2116                 return 1;
2117         return 0;
2118 }
2119
2120 static int __init intel_opregion_present(void)
2121 {
2122         int opregion = 0;
2123         struct pci_dev *dev = NULL;
2124         u32 address;
2125
2126         for_each_pci_dev(dev) {
2127                 if ((dev->class >> 8) != PCI_CLASS_DISPLAY_VGA)
2128                         continue;
2129                 if (dev->vendor != PCI_VENDOR_ID_INTEL)
2130                         continue;
2131                 /* We don't want to poke around undefined i740 registers */
2132                 if (is_i740(dev))
2133                         continue;
2134                 pci_read_config_dword(dev, 0xfc, &address);
2135                 if (!address)
2136                         continue;
2137                 opregion = 1;
2138         }
2139         return opregion;
2140 }
2141
2142 int acpi_video_register(void)
2143 {
2144         int result = 0;
2145         if (register_count) {
2146                 /*
2147                  * if the function of acpi_video_register is already called,
2148                  * don't register the acpi_vide_bus again and return no error.
2149                  */
2150                 return 0;
2151         }
2152
2153         mutex_init(&video_list_lock);
2154         INIT_LIST_HEAD(&video_bus_head);
2155
2156         result = acpi_bus_register_driver(&acpi_video_bus);
2157         if (result < 0)
2158                 return -ENODEV;
2159
2160         /*
2161          * When the acpi_video_bus is loaded successfully, increase
2162          * the counter reference.
2163          */
2164         register_count = 1;
2165
2166         return 0;
2167 }
2168 EXPORT_SYMBOL(acpi_video_register);
2169
2170 void acpi_video_unregister(void)
2171 {
2172         if (!register_count) {
2173                 /*
2174                  * If the acpi video bus is already unloaded, don't
2175                  * unload it again and return directly.
2176                  */
2177                 return;
2178         }
2179         acpi_bus_unregister_driver(&acpi_video_bus);
2180
2181         register_count = 0;
2182
2183         return;
2184 }
2185 EXPORT_SYMBOL(acpi_video_unregister);
2186
2187 void acpi_video_unregister_backlight(void)
2188 {
2189         struct acpi_video_bus *video;
2190
2191         if (!register_count)
2192                 return;
2193
2194         mutex_lock(&video_list_lock);
2195         list_for_each_entry(video, &video_bus_head, entry)
2196                 acpi_video_bus_unregister_backlight(video);
2197         mutex_unlock(&video_list_lock);
2198 }
2199 EXPORT_SYMBOL(acpi_video_unregister_backlight);
2200
2201 /*
2202  * This is kind of nasty. Hardware using Intel chipsets may require
2203  * the video opregion code to be run first in order to initialise
2204  * state before any ACPI video calls are made. To handle this we defer
2205  * registration of the video class until the opregion code has run.
2206  */
2207
2208 static int __init acpi_video_init(void)
2209 {
2210         dmi_check_system(video_dmi_table);
2211
2212         if (intel_opregion_present())
2213                 return 0;
2214
2215         return acpi_video_register();
2216 }
2217
2218 static void __exit acpi_video_exit(void)
2219 {
2220         acpi_video_unregister();
2221
2222         return;
2223 }
2224
2225 module_init(acpi_video_init);
2226 module_exit(acpi_video_exit);