drivers/acpi/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  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  21  */
  22
  23 #include <linux/kernel.h>
  24 #include <linux/module.h>
  25 #include <linux/init.h>
  26 #include <linux/types.h>
  27 #include <linux/list.h>
  28 #include <linux/mutex.h>
  29 #include <linux/input.h>
  30 #include <linux/backlight.h>
  31 #include <linux/thermal.h>
  32 #include <linux/sort.h>
  33 #include <linux/pci.h>
  34 #include <linux/pci_ids.h>
  35 #include <linux/slab.h>
  36 #include <linux/dmi.h>
  37 #include <linux/suspend.h>
  38 #include <linux/acpi.h>
  39 #include <acpi/video.h>
  40 #include <linux/uaccess.h>
  41
  42 #define PREFIX "ACPI: "
  43
  44 #define ACPI_VIDEO_BUS_NAME             "Video Bus"
  45 #define ACPI_VIDEO_DEVICE_NAME          "Video Device"
  46
  47 #define MAX_NAME_LEN    20
  48
  49 #define _COMPONENT              ACPI_VIDEO_COMPONENT
  50 ACPI_MODULE_NAME("video");
  51
  52 MODULE_AUTHOR("Bruno Ducrot");
  53 MODULE_DESCRIPTION("ACPI Video Driver");
  54 MODULE_LICENSE("GPL");
  55
  56 static bool brightness_switch_enabled = true;
  57 module_param(brightness_switch_enabled, bool, 0644);
  58
  59 /*
  60  * By default, we don't allow duplicate ACPI video bus devices
  61  * under the same VGA controller
  62  */
  63 static bool allow_duplicates;
  64 module_param(allow_duplicates, bool, 0644);
  65
  66 static int disable_backlight_sysfs_if = -1;
  67 module_param(disable_backlight_sysfs_if, int, 0444);
  68
  69 #define REPORT_OUTPUT_KEY_EVENTS                0x01
  70 #define REPORT_BRIGHTNESS_KEY_EVENTS            0x02
  71 static int report_key_events = -1;
  72 module_param(report_key_events, int, 0644);
  73 MODULE_PARM_DESC(report_key_events,
  74         "0: none, 1: output changes, 2: brightness changes, 3: all");
  75
  76 static int hw_changes_brightness = -1;
  77 module_param(hw_changes_brightness, int, 0644);
  78 MODULE_PARM_DESC(hw_changes_brightness,
  79         "Set this to 1 on buggy hw which changes the brightness itself when "
  80         "a hotkey is pressed: -1: auto, 0: normal 1: hw-changes-brightness");
  81
  82 /*
  83  * Whether the struct acpi_video_device_attrib::device_id_scheme bit should be
  84  * assumed even if not actually set.
  85  */
  86 static bool device_id_scheme = false;
  87 module_param(device_id_scheme, bool, 0444);
  88
  89 static int only_lcd = -1;
  90 module_param(only_lcd, int, 0444);
  91
  92 static int register_count;
  93 static DEFINE_MUTEX(register_count_mutex);
  94 static DEFINE_MUTEX(video_list_lock);
  95 static LIST_HEAD(video_bus_head);
  96 static int acpi_video_bus_add(struct acpi_device *device);
  97 static int acpi_video_bus_remove(struct acpi_device *device);
  98 static void acpi_video_bus_notify(struct acpi_device *device, u32 event);
  99 void acpi_video_detect_exit(void);
 100
 101 /*
 102  * Indices in the _BCL method response: the first two items are special,
 103  * the rest are all supported levels.
 104  *
 105  * See page 575 of the ACPI spec 3.0
 106  */
 107 enum acpi_video_level_idx {
 108         ACPI_VIDEO_AC_LEVEL,            /* level when machine has full power */
 109         ACPI_VIDEO_BATTERY_LEVEL,       /* level when machine is on batteries */
 110         ACPI_VIDEO_FIRST_LEVEL,         /* actual supported levels begin here */
 111 };
 112
 113 static const struct acpi_device_id video_device_ids[] = {
 114         {ACPI_VIDEO_HID, 0},
 115         {"", 0},
 116 };
 117 MODULE_DEVICE_TABLE(acpi, video_device_ids);
 118
 119 static struct acpi_driver acpi_video_bus = {
 120         .name = "video",
 121         .class = ACPI_VIDEO_CLASS,
 122         .ids = video_device_ids,
 123         .ops = {
 124                 .add = acpi_video_bus_add,
 125                 .remove = acpi_video_bus_remove,
 126                 .notify = acpi_video_bus_notify,
 127                 },
 128 };
 129
 130 struct acpi_video_bus_flags {
 131         u8 multihead:1;         /* can switch video heads */
 132         u8 rom:1;               /* can retrieve a video rom */
 133         u8 post:1;              /* can configure the head to */
 134         u8 reserved:5;
 135 };
 136
 137 struct acpi_video_bus_cap {
 138         u8 _DOS:1;              /* Enable/Disable output switching */
 139         u8 _DOD:1;              /* Enumerate all devices attached to display adapter */
 140         u8 _ROM:1;              /* Get ROM Data */
 141         u8 _GPD:1;              /* Get POST Device */
 142         u8 _SPD:1;              /* Set POST Device */
 143         u8 _VPO:1;              /* Video POST Options */
 144         u8 reserved:2;
 145 };
 146
 147 struct acpi_video_device_attrib {
 148         u32 display_index:4;    /* A zero-based instance of the Display */
 149         u32 display_port_attachment:4;  /* This field differentiates the display type */
 150         u32 display_type:4;     /* Describe the specific type in use */
 151         u32 vendor_specific:4;  /* Chipset Vendor Specific */
 152         u32 bios_can_detect:1;  /* BIOS can detect the device */
 153         u32 depend_on_vga:1;    /* Non-VGA output device whose power is related to
 154                                    the VGA device. */
 155         u32 pipe_id:3;          /* For VGA multiple-head devices. */
 156         u32 reserved:10;        /* Must be 0 */
 157
 158         /*
 159          * The device ID might not actually follow the scheme described by this
 160          * struct acpi_video_device_attrib. If it does, then this bit
 161          * device_id_scheme is set; otherwise, other fields should be ignored.
 162          *
 163          * (but also see the global flag device_id_scheme)
 164          */
 165         u32 device_id_scheme:1;
 166 };
 167
 168 struct acpi_video_enumerated_device {
 169         union {
 170                 u32 int_val;
 171                 struct acpi_video_device_attrib attrib;
 172         } value;
 173         struct acpi_video_device *bind_info;
 174 };
 175
 176 struct acpi_video_bus {
 177         struct acpi_device *device;
 178         bool backlight_registered;
 179         u8 dos_setting;
 180         struct acpi_video_enumerated_device *attached_array;
 181         u8 attached_count;
 182         u8 child_count;
 183         struct acpi_video_bus_cap cap;
 184         struct acpi_video_bus_flags flags;
 185         struct list_head video_device_list;
 186         struct mutex device_list_lock;  /* protects video_device_list */
 187         struct list_head entry;
 188         struct input_dev *input;
 189         char phys[32];  /* for input device */
 190         struct notifier_block pm_nb;
 191 };
 192
 193 struct acpi_video_device_flags {
 194         u8 crt:1;
 195         u8 lcd:1;
 196         u8 tvout:1;
 197         u8 dvi:1;
 198         u8 bios:1;
 199         u8 unknown:1;
 200         u8 notify:1;
 201         u8 reserved:1;
 202 };
 203
 204 struct acpi_video_device_cap {
 205         u8 _ADR:1;              /* Return the unique ID */
 206         u8 _BCL:1;              /* Query list of brightness control levels supported */
 207         u8 _BCM:1;              /* Set the brightness level */
 208         u8 _BQC:1;              /* Get current brightness level */
 209         u8 _BCQ:1;              /* Some buggy BIOS uses _BCQ instead of _BQC */
 210         u8 _DDC:1;              /* Return the EDID for this device */
 211 };
 212
 213 struct acpi_video_device {
 214         unsigned long device_id;
 215         struct acpi_video_device_flags flags;
 216         struct acpi_video_device_cap cap;
 217         struct list_head entry;
 218         struct delayed_work switch_brightness_work;
 219         int switch_brightness_event;
 220         struct acpi_video_bus *video;
 221         struct acpi_device *dev;
 222         struct acpi_video_device_brightness *brightness;
 223         struct backlight_device *backlight;
 224         struct thermal_cooling_device *cooling_dev;
 225 };
 226
 227 static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data);
 228 static void acpi_video_device_rebind(struct acpi_video_bus *video);
 229 static void acpi_video_device_bind(struct acpi_video_bus *video,
 230                                    struct acpi_video_device *device);
 231 static int acpi_video_device_enumerate(struct acpi_video_bus *video);
 232 static int acpi_video_device_lcd_set_level(struct acpi_video_device *device,
 233                         int level);
 234 static int acpi_video_device_lcd_get_level_current(
 235                         struct acpi_video_device *device,
 236                         unsigned long long *level, bool raw);
 237 static int acpi_video_get_next_level(struct acpi_video_device *device,
 238                                      u32 level_current, u32 event);
 239 static void acpi_video_switch_brightness(struct work_struct *work);
 240
 241 /* backlight device sysfs support */
 242 static int acpi_video_get_brightness(struct backlight_device *bd)
 243 {
 244         unsigned long long cur_level;
 245         int i;
 246         struct acpi_video_device *vd = bl_get_data(bd);
 247
 248         if (acpi_video_device_lcd_get_level_current(vd, &cur_level, false))
 249                 return -EINVAL;
 250         for (i = ACPI_VIDEO_FIRST_LEVEL; i < vd->brightness->count; i++) {
 251                 if (vd->brightness->levels[i] == cur_level)
 252                         return i - ACPI_VIDEO_FIRST_LEVEL;
 253         }
 254         return 0;
 255 }
 256
 257 static int acpi_video_set_brightness(struct backlight_device *bd)
 258 {
 259         int request_level = bd->props.brightness + ACPI_VIDEO_FIRST_LEVEL;
 260         struct acpi_video_device *vd = bl_get_data(bd);
 261
 262         cancel_delayed_work(&vd->switch_brightness_work);
 263         return acpi_video_device_lcd_set_level(vd,
 264                                 vd->brightness->levels[request_level]);
 265 }
 266
 267 static const struct backlight_ops acpi_backlight_ops = {
 268         .get_brightness = acpi_video_get_brightness,
 269         .update_status  = acpi_video_set_brightness,
 270 };
 271
 272 /* thermal cooling device callbacks */
 273 static int video_get_max_state(struct thermal_cooling_device *cooling_dev,
 274                                unsigned long *state)
 275 {
 276         struct acpi_device *device = cooling_dev->devdata;
 277         struct acpi_video_device *video = acpi_driver_data(device);
 278
 279         *state = video->brightness->count - ACPI_VIDEO_FIRST_LEVEL - 1;
 280         return 0;
 281 }
 282
 283 static int video_get_cur_state(struct thermal_cooling_device *cooling_dev,
 284                                unsigned long *state)
 285 {
 286         struct acpi_device *device = cooling_dev->devdata;
 287         struct acpi_video_device *video = acpi_driver_data(device);
 288         unsigned long long level;
 289         int offset;
 290
 291         if (acpi_video_device_lcd_get_level_current(video, &level, false))
 292                 return -EINVAL;
 293         for (offset = ACPI_VIDEO_FIRST_LEVEL; offset < video->brightness->count;
 294              offset++)
 295                 if (level == video->brightness->levels[offset]) {
 296                         *state = video->brightness->count - offset - 1;
 297                         return 0;
 298                 }
 299
 300         return -EINVAL;
 301 }
 302
 303 static int
 304 video_set_cur_state(struct thermal_cooling_device *cooling_dev, unsigned long state)
 305 {
 306         struct acpi_device *device = cooling_dev->devdata;
 307         struct acpi_video_device *video = acpi_driver_data(device);
 308         int level;
 309
 310         if (state >= video->brightness->count - ACPI_VIDEO_FIRST_LEVEL)
 311                 return -EINVAL;
 312
 313         state = video->brightness->count - state;
 314         level = video->brightness->levels[state - 1];
 315         return acpi_video_device_lcd_set_level(video, level);
 316 }
 317
 318 static const struct thermal_cooling_device_ops video_cooling_ops = {
 319         .get_max_state = video_get_max_state,
 320         .get_cur_state = video_get_cur_state,
 321         .set_cur_state = video_set_cur_state,
 322 };
 323
 324 /*
 325  * --------------------------------------------------------------------------
 326  *                             Video Management
 327  * --------------------------------------------------------------------------
 328  */
 329
 330 static int
 331 acpi_video_device_lcd_query_levels(acpi_handle handle,
 332                                    union acpi_object **levels)
 333 {
 334         int status;
 335         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 336         union acpi_object *obj;
 337
 338
 339         *levels = NULL;
 340
 341         status = acpi_evaluate_object(handle, "_BCL", NULL, &buffer);
 342         if (!ACPI_SUCCESS(status))
 343                 return status;
 344         obj = (union acpi_object *)buffer.pointer;
 345         if (!obj || (obj->type != ACPI_TYPE_PACKAGE)) {
 346                 printk(KERN_ERR PREFIX "Invalid _BCL data\n");
 347                 status = -EFAULT;
 348                 goto err;
 349         }
 350
 351         *levels = obj;
 352
 353         return 0;
 354
 355 err:
 356         kfree(buffer.pointer);
 357
 358         return status;
 359 }
 360
 361 static int
 362 acpi_video_device_lcd_set_level(struct acpi_video_device *device, int level)
 363 {
 364         int status;
 365         int state;
 366
 367         status = acpi_execute_simple_method(device->dev->handle,
 368                                             "_BCM", level);
 369         if (ACPI_FAILURE(status)) {
 370                 ACPI_ERROR((AE_INFO, "Evaluating _BCM failed"));
 371                 return -EIO;
 372         }
 373
 374         device->brightness->curr = level;
 375         for (state = ACPI_VIDEO_FIRST_LEVEL; state < device->brightness->count;
 376              state++)
 377                 if (level == device->brightness->levels[state]) {
 378                         if (device->backlight)
 379                                 device->backlight->props.brightness =
 380                                         state - ACPI_VIDEO_FIRST_LEVEL;
 381                         return 0;
 382                 }
 383
 384         ACPI_ERROR((AE_INFO, "Current brightness invalid"));
 385         return -EINVAL;
 386 }
 387
 388 /*
 389  * For some buggy _BQC methods, we need to add a constant value to
 390  * the _BQC return value to get the actual current brightness level
 391  */
 392
 393 static int bqc_offset_aml_bug_workaround;
 394 static int video_set_bqc_offset(const struct dmi_system_id *d)
 395 {
 396         bqc_offset_aml_bug_workaround = 9;
 397         return 0;
 398 }
 399
 400 static int video_disable_backlight_sysfs_if(
 401         const struct dmi_system_id *d)
 402 {
 403         if (disable_backlight_sysfs_if == -1)
 404                 disable_backlight_sysfs_if = 1;
 405         return 0;
 406 }
 407
 408 static int video_set_device_id_scheme(const struct dmi_system_id *d)
 409 {
 410         device_id_scheme = true;
 411         return 0;
 412 }
 413
 414 static int video_enable_only_lcd(const struct dmi_system_id *d)
 415 {
 416         only_lcd = true;
 417         return 0;
 418 }
 419
 420 static int video_set_report_key_events(const struct dmi_system_id *id)
 421 {
 422         if (report_key_events == -1)
 423                 report_key_events = (uintptr_t)id->driver_data;
 424         return 0;
 425 }
 426
 427 static int video_hw_changes_brightness(
 428         const struct dmi_system_id *d)
 429 {
 430         if (hw_changes_brightness == -1)
 431                 hw_changes_brightness = 1;
 432         return 0;
 433 }
 434
 435 static const struct dmi_system_id video_dmi_table[] = {
 436         /*
 437          * Broken _BQC workaround http://bugzilla.kernel.org/show_bug.cgi?id=13121
 438          */
 439         {
 440          .callback = video_set_bqc_offset,
 441          .ident = "Acer Aspire 5720",
 442          .matches = {
 443                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
 444                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5720"),
 445                 },
 446         },
 447         {
 448          .callback = video_set_bqc_offset,
 449          .ident = "Acer Aspire 5710Z",
 450          .matches = {
 451                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
 452                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5710Z"),
 453                 },
 454         },
 455         {
 456          .callback = video_set_bqc_offset,
 457          .ident = "eMachines E510",
 458          .matches = {
 459                 DMI_MATCH(DMI_BOARD_VENDOR, "EMACHINES"),
 460                 DMI_MATCH(DMI_PRODUCT_NAME, "eMachines E510"),
 461                 },
 462         },
 463         {
 464          .callback = video_set_bqc_offset,
 465          .ident = "Acer Aspire 5315",
 466          .matches = {
 467                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
 468                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5315"),
 469                 },
 470         },
 471         {
 472          .callback = video_set_bqc_offset,
 473          .ident = "Acer Aspire 7720",
 474          .matches = {
 475                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
 476                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 7720"),
 477                 },
 478         },
 479
 480         /*
 481          * Some machines have a broken acpi-video interface for brightness
 482          * control, but still need an acpi_video_device_lcd_set_level() call
 483          * on resume to turn the backlight power on.  We Enable backlight
 484          * control on these systems, but do not register a backlight sysfs
 485          * as brightness control does not work.
 486          */
 487         {
 488          /* https://bugzilla.kernel.org/show_bug.cgi?id=21012 */
 489          .callback = video_disable_backlight_sysfs_if,
 490          .ident = "Toshiba Portege R700",
 491          .matches = {
 492                 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
 493                 DMI_MATCH(DMI_PRODUCT_NAME, "PORTEGE R700"),
 494                 },
 495         },
 496         {
 497          /* https://bugs.freedesktop.org/show_bug.cgi?id=82634 */
 498          .callback = video_disable_backlight_sysfs_if,
 499          .ident = "Toshiba Portege R830",
 500          .matches = {
 501                 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
 502                 DMI_MATCH(DMI_PRODUCT_NAME, "PORTEGE R830"),
 503                 },
 504         },
 505         {
 506          /* https://bugzilla.kernel.org/show_bug.cgi?id=21012 */
 507          .callback = video_disable_backlight_sysfs_if,
 508          .ident = "Toshiba Satellite R830",
 509          .matches = {
 510                 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
 511                 DMI_MATCH(DMI_PRODUCT_NAME, "SATELLITE R830"),
 512                 },
 513         },
 514         {
 515          .callback = video_disable_backlight_sysfs_if,
 516          .ident = "Toshiba Satellite Z830",
 517          .matches = {
 518                 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
 519                 DMI_MATCH(DMI_PRODUCT_NAME, "SATELLITE Z830"),
 520                 },
 521         },
 522         {
 523          .callback = video_disable_backlight_sysfs_if,
 524          .ident = "Toshiba Portege Z830",
 525          .matches = {
 526                 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
 527                 DMI_MATCH(DMI_PRODUCT_NAME, "PORTEGE Z830"),
 528                 },
 529         },
 530         /*
 531          * Some machine's _DOD IDs don't have bit 31(Device ID Scheme) set
 532          * but the IDs actually follow the Device ID Scheme.
 533          */
 534         {
 535          /* https://bugzilla.kernel.org/show_bug.cgi?id=104121 */
 536          .callback = video_set_device_id_scheme,
 537          .ident = "ESPRIMO Mobile M9410",
 538          .matches = {
 539                 DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU SIEMENS"),
 540                 DMI_MATCH(DMI_PRODUCT_NAME, "ESPRIMO Mobile M9410"),
 541                 },
 542         },
 543         /*
 544          * Some machines have multiple video output devices, but only the one
 545          * that is the type of LCD can do the backlight control so we should not
 546          * register backlight interface for other video output devices.
 547          */
 548         {
 549          /* https://bugzilla.kernel.org/show_bug.cgi?id=104121 */
 550          .callback = video_enable_only_lcd,
 551          .ident = "ESPRIMO Mobile M9410",
 552          .matches = {
 553                 DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU SIEMENS"),
 554                 DMI_MATCH(DMI_PRODUCT_NAME, "ESPRIMO Mobile M9410"),
 555                 },
 556         },
 557         /*
 558          * Some machines report wrong key events on the acpi-bus, suppress
 559          * key event reporting on these.  Note this is only intended to work
 560          * around events which are plain wrong. In some cases we get double
 561          * events, in this case acpi-video is considered the canonical source
 562          * and the events from the other source should be filtered. E.g.
 563          * by calling acpi_video_handles_brightness_key_presses() from the
 564          * vendor acpi/wmi driver or by using /lib/udev/hwdb.d/60-keyboard.hwdb
 565          */
 566         {
 567          .callback = video_set_report_key_events,
 568          .driver_data = (void *)((uintptr_t)REPORT_OUTPUT_KEY_EVENTS),
 569          .ident = "Dell Vostro V131",
 570          .matches = {
 571                 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 572                 DMI_MATCH(DMI_PRODUCT_NAME, "Vostro V131"),
 573                 },
 574         },
 575         {
 576          .callback = video_set_report_key_events,
 577          .driver_data = (void *)((uintptr_t)REPORT_BRIGHTNESS_KEY_EVENTS),
 578          .ident = "Dell Vostro 3350",
 579          .matches = {
 580                 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 581                 DMI_MATCH(DMI_PRODUCT_NAME, "Vostro 3350"),
 582                 },
 583         },
 584         /*
 585          * Some machines change the brightness themselves when a brightness
 586          * hotkey gets pressed, despite us telling them not to. In this case
 587          * acpi_video_device_notify() should only call backlight_force_update(
 588          * BACKLIGHT_UPDATE_HOTKEY) and not do anything else.
 589          */
 590         {
 591          /* https://bugzilla.kernel.org/show_bug.cgi?id=204077 */
 592          .callback = video_hw_changes_brightness,
 593          .ident = "Packard Bell EasyNote MZ35",
 594          .matches = {
 595                 DMI_MATCH(DMI_SYS_VENDOR, "Packard Bell"),
 596                 DMI_MATCH(DMI_PRODUCT_NAME, "EasyNote MZ35"),
 597                 },
 598         },
 599         {}
 600 };
 601
 602 static unsigned long long
 603 acpi_video_bqc_value_to_level(struct acpi_video_device *device,
 604                               unsigned long long bqc_value)
 605 {
 606         unsigned long long level;
 607
 608         if (device->brightness->flags._BQC_use_index) {
 609                 /*
 610                  * _BQC returns an index that doesn't account for the first 2
 611                  * items with special meaning (see enum acpi_video_level_idx),
 612                  * so we need to compensate for that by offsetting ourselves
 613                  */
 614                 if (device->brightness->flags._BCL_reversed)
 615                         bqc_value = device->brightness->count -
 616                                 ACPI_VIDEO_FIRST_LEVEL - 1 - bqc_value;
 617
 618                 level = device->brightness->levels[bqc_value +
 619                                                    ACPI_VIDEO_FIRST_LEVEL];
 620         } else {
 621                 level = bqc_value;
 622         }
 623
 624         level += bqc_offset_aml_bug_workaround;
 625
 626         return level;
 627 }
 628
 629 static int
 630 acpi_video_device_lcd_get_level_current(struct acpi_video_device *device,
 631                                         unsigned long long *level, bool raw)
 632 {
 633         acpi_status status = AE_OK;
 634         int i;
 635
 636         if (device->cap._BQC || device->cap._BCQ) {
 637                 char *buf = device->cap._BQC ? "_BQC" : "_BCQ";
 638
 639                 status = acpi_evaluate_integer(device->dev->handle, buf,
 640                                                 NULL, level);
 641                 if (ACPI_SUCCESS(status)) {
 642                         if (raw) {
 643                                 /*
 644                                  * Caller has indicated he wants the raw
 645                                  * value returned by _BQC, so don't furtherly
 646                                  * mess with the value.
 647                                  */
 648                                 return 0;
 649                         }
 650
 651                         *level = acpi_video_bqc_value_to_level(device, *level);
 652
 653                         for (i = ACPI_VIDEO_FIRST_LEVEL;
 654                              i < device->brightness->count; i++)
 655                                 if (device->brightness->levels[i] == *level) {
 656                                         device->brightness->curr = *level;
 657                                         return 0;
 658                                 }
 659                         /*
 660                          * BQC returned an invalid level.
 661                          * Stop using it.
 662                          */
 663                         ACPI_WARNING((AE_INFO,
 664                                       "%s returned an invalid level",
 665                                       buf));
 666                         device->cap._BQC = device->cap._BCQ = 0;
 667                 } else {
 668                         /*
 669                          * Fixme:
 670                          * should we return an error or ignore this failure?
 671                          * dev->brightness->curr is a cached value which stores
 672                          * the correct current backlight level in most cases.
 673                          * ACPI video backlight still works w/ buggy _BQC.
 674                          * http://bugzilla.kernel.org/show_bug.cgi?id=12233
 675                          */
 676                         ACPI_WARNING((AE_INFO, "Evaluating %s failed", buf));
 677                         device->cap._BQC = device->cap._BCQ = 0;
 678                 }
 679         }
 680
 681         *level = device->brightness->curr;
 682         return 0;
 683 }
 684
 685 static int
 686 acpi_video_device_EDID(struct acpi_video_device *device,
 687                        union acpi_object **edid, ssize_t length)
 688 {
 689         int status;
 690         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 691         union acpi_object *obj;
 692         union acpi_object arg0 = { ACPI_TYPE_INTEGER };
 693         struct acpi_object_list args = { 1, &arg0 };
 694
 695
 696         *edid = NULL;
 697
 698         if (!device)
 699                 return -ENODEV;
 700         if (length == 128)
 701                 arg0.integer.value = 1;
 702         else if (length == 256)
 703                 arg0.integer.value = 2;
 704         else
 705                 return -EINVAL;
 706
 707         status = acpi_evaluate_object(device->dev->handle, "_DDC", &args, &buffer);
 708         if (ACPI_FAILURE(status))
 709                 return -ENODEV;
 710
 711         obj = buffer.pointer;
 712
 713         if (obj && obj->type == ACPI_TYPE_BUFFER)
 714                 *edid = obj;
 715         else {
 716                 printk(KERN_ERR PREFIX "Invalid _DDC data\n");
 717                 status = -EFAULT;
 718                 kfree(obj);
 719         }
 720
 721         return status;
 722 }
 723
 724 /* bus */
 725
 726 /*
 727  *  Arg:
 728  *      video           : video bus device pointer
 729  *      bios_flag       :
 730  *              0.      The system BIOS should NOT automatically switch(toggle)
 731  *                      the active display output.
 732  *              1.      The system BIOS should automatically switch (toggle) the
 733  *                      active display output. No switch event.
 734  *              2.      The _DGS value should be locked.
 735  *              3.      The system BIOS should not automatically switch (toggle) the
 736  *                      active display output, but instead generate the display switch
 737  *                      event notify code.
 738  *      lcd_flag        :
 739  *              0.      The system BIOS should automatically control the brightness level
 740  *                      of the LCD when the power changes from AC to DC
 741  *              1.      The system BIOS should NOT automatically control the brightness
 742  *                      level of the LCD when the power changes from AC to DC.
 743  *  Return Value:
 744  *              -EINVAL wrong arg.
 745  */
 746
 747 static int
 748 acpi_video_bus_DOS(struct acpi_video_bus *video, int bios_flag, int lcd_flag)
 749 {
 750         acpi_status status;
 751
 752         if (!video->cap._DOS)
 753                 return 0;
 754
 755         if (bios_flag < 0 || bios_flag > 3 || lcd_flag < 0 || lcd_flag > 1)
 756                 return -EINVAL;
 757         video->dos_setting = (lcd_flag << 2) | bios_flag;
 758         status = acpi_execute_simple_method(video->device->handle, "_DOS",
 759                                             (lcd_flag << 2) | bios_flag);
 760         if (ACPI_FAILURE(status))
 761                 return -EIO;
 762
 763         return 0;
 764 }
 765
 766 /*
 767  * Simple comparison function used to sort backlight levels.
 768  */
 769
 770 static int
 771 acpi_video_cmp_level(const void *a, const void *b)
 772 {
 773         return *(int *)a - *(int *)b;
 774 }
 775
 776 /*
 777  * Decides if _BQC/_BCQ for this system is usable
 778  *
 779  * We do this by changing the level first and then read out the current
 780  * brightness level, if the value does not match, find out if it is using
 781  * index. If not, clear the _BQC/_BCQ capability.
 782  */
 783 static int acpi_video_bqc_quirk(struct acpi_video_device *device,
 784                                 int max_level, int current_level)
 785 {
 786         struct acpi_video_device_brightness *br = device->brightness;
 787         int result;
 788         unsigned long long level;
 789         int test_level;
 790
 791         /* don't mess with existing known broken systems */
 792         if (bqc_offset_aml_bug_workaround)
 793                 return 0;
 794
 795         /*
 796          * Some systems always report current brightness level as maximum
 797          * through _BQC, we need to test another value for them. However,
 798          * there is a subtlety:
 799          *
 800          * If the _BCL package ordering is descending, the first level
 801          * (br->levels[2]) is likely to be 0, and if the number of levels
 802          * matches the number of steps, we might confuse a returned level to
 803          * mean the index.
 804          *
 805          * For example:
 806          *
 807          *     current_level = max_level = 100
 808          *     test_level = 0
 809          *     returned level = 100
 810          *
 811          * In this case 100 means the level, not the index, and _BCM failed.
 812          * Still, if the _BCL package ordering is descending, the index of
 813          * level 0 is also 100, so we assume _BQC is indexed, when it's not.
 814          *
 815          * This causes all _BQC calls to return bogus values causing weird
 816          * behavior from the user's perspective.  For example:
 817          *
 818          * xbacklight -set 10; xbacklight -set 20;
 819          *
 820          * would flash to 90% and then slowly down to the desired level (20).
 821          *
 822          * The solution is simple; test anything other than the first level
 823          * (e.g. 1).
 824          */
 825         test_level = current_level == max_level
 826                 ? br->levels[ACPI_VIDEO_FIRST_LEVEL + 1]
 827                 : max_level;
 828
 829         result = acpi_video_device_lcd_set_level(device, test_level);
 830         if (result)
 831                 return result;
 832
 833         result = acpi_video_device_lcd_get_level_current(device, &level, true);
 834         if (result)
 835                 return result;
 836
 837         if (level != test_level) {
 838                 /* buggy _BQC found, need to find out if it uses index */
 839                 if (level < br->count) {
 840                         if (br->flags._BCL_reversed)
 841                                 level = br->count - ACPI_VIDEO_FIRST_LEVEL - 1 - level;
 842                         if (br->levels[level + ACPI_VIDEO_FIRST_LEVEL] == test_level)
 843                                 br->flags._BQC_use_index = 1;
 844                 }
 845
 846                 if (!br->flags._BQC_use_index)
 847                         device->cap._BQC = device->cap._BCQ = 0;
 848         }
 849
 850         return 0;
 851 }
 852
 853 int acpi_video_get_levels(struct acpi_device *device,
 854                           struct acpi_video_device_brightness **dev_br,
 855                           int *pmax_level)
 856 {
 857         union acpi_object *obj = NULL;
 858         int i, max_level = 0, count = 0, level_ac_battery = 0;
 859         union acpi_object *o;
 860         struct acpi_video_device_brightness *br = NULL;
 861         int result = 0;
 862         u32 value;
 863
 864         if (!ACPI_SUCCESS(acpi_video_device_lcd_query_levels(device->handle,
 865                                                                 &obj))) {
 866                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Could not query available "
 867                                                 "LCD brightness level\n"));
 868                 result = -ENODEV;
 869                 goto out;
 870         }
 871
 872         if (obj->package.count < ACPI_VIDEO_FIRST_LEVEL) {
 873                 result = -EINVAL;
 874                 goto out;
 875         }
 876
 877         br = kzalloc(sizeof(*br), GFP_KERNEL);
 878         if (!br) {
 879                 printk(KERN_ERR "can't allocate memory\n");
 880                 result = -ENOMEM;
 881                 goto out;
 882         }
 883
 884         /*
 885          * Note that we have to reserve 2 extra items (ACPI_VIDEO_FIRST_LEVEL),
 886          * in order to account for buggy BIOS which don't export the first two
 887          * special levels (see below)
 888          */
 889         br->levels = kmalloc_array(obj->package.count + ACPI_VIDEO_FIRST_LEVEL,
 890                                    sizeof(*br->levels),
 891                                    GFP_KERNEL);
 892         if (!br->levels) {
 893                 result = -ENOMEM;
 894                 goto out_free;
 895         }
 896
 897         for (i = 0; i < obj->package.count; i++) {
 898                 o = (union acpi_object *)&obj->package.elements[i];
 899                 if (o->type != ACPI_TYPE_INTEGER) {
 900                         printk(KERN_ERR PREFIX "Invalid data\n");
 901                         continue;
 902                 }
 903                 value = (u32) o->integer.value;
 904                 /* Skip duplicate entries */
 905                 if (count > ACPI_VIDEO_FIRST_LEVEL
 906                     && br->levels[count - 1] == value)
 907                         continue;
 908
 909                 br->levels[count] = value;
 910
 911                 if (br->levels[count] > max_level)
 912                         max_level = br->levels[count];
 913                 count++;
 914         }
 915
 916         /*
 917          * some buggy BIOS don't export the levels
 918          * when machine is on AC/Battery in _BCL package.
 919          * In this case, the first two elements in _BCL packages
 920          * are also supported brightness levels that OS should take care of.
 921          */
 922         for (i = ACPI_VIDEO_FIRST_LEVEL; i < count; i++) {
 923                 if (br->levels[i] == br->levels[ACPI_VIDEO_AC_LEVEL])
 924                         level_ac_battery++;
 925                 if (br->levels[i] == br->levels[ACPI_VIDEO_BATTERY_LEVEL])
 926                         level_ac_battery++;
 927         }
 928
 929         if (level_ac_battery < ACPI_VIDEO_FIRST_LEVEL) {
 930                 level_ac_battery = ACPI_VIDEO_FIRST_LEVEL - level_ac_battery;
 931                 br->flags._BCL_no_ac_battery_levels = 1;
 932                 for (i = (count - 1 + level_ac_battery);
 933                      i >= ACPI_VIDEO_FIRST_LEVEL; i--)
 934                         br->levels[i] = br->levels[i - level_ac_battery];
 935                 count += level_ac_battery;
 936         } else if (level_ac_battery > ACPI_VIDEO_FIRST_LEVEL)
 937                 ACPI_ERROR((AE_INFO, "Too many duplicates in _BCL package"));
 938
 939         /* Check if the _BCL package is in a reversed order */
 940         if (max_level == br->levels[ACPI_VIDEO_FIRST_LEVEL]) {
 941                 br->flags._BCL_reversed = 1;
 942                 sort(&br->levels[ACPI_VIDEO_FIRST_LEVEL],
 943                      count - ACPI_VIDEO_FIRST_LEVEL,
 944                      sizeof(br->levels[ACPI_VIDEO_FIRST_LEVEL]),
 945                      acpi_video_cmp_level, NULL);
 946         } else if (max_level != br->levels[count - 1])
 947                 ACPI_ERROR((AE_INFO,
 948                             "Found unordered _BCL package"));
 949
 950         br->count = count;
 951         *dev_br = br;
 952         if (pmax_level)
 953                 *pmax_level = max_level;
 954
 955 out:
 956         kfree(obj);
 957         return result;
 958 out_free:
 959         kfree(br);
 960         goto out;
 961 }
 962 EXPORT_SYMBOL(acpi_video_get_levels);
 963
 964 /*
 965  *  Arg:
 966  *      device  : video output device (LCD, CRT, ..)
 967  *
 968  *  Return Value:
 969  *      Maximum brightness level
 970  *
 971  *  Allocate and initialize device->brightness.
 972  */
 973
 974 static int
 975 acpi_video_init_brightness(struct acpi_video_device *device)
 976 {
 977         int i, max_level = 0;
 978         unsigned long long level, level_old;
 979         struct acpi_video_device_brightness *br = NULL;
 980         int result = -EINVAL;
 981
 982         result = acpi_video_get_levels(device->dev, &br, &max_level);
 983         if (result)
 984                 return result;
 985         device->brightness = br;
 986
 987         /* _BQC uses INDEX while _BCL uses VALUE in some laptops */
 988         br->curr = level = max_level;
 989
 990         if (!device->cap._BQC)
 991                 goto set_level;
 992
 993         result = acpi_video_device_lcd_get_level_current(device,
 994                                                          &level_old, true);
 995         if (result)
 996                 goto out_free_levels;
 997
 998         result = acpi_video_bqc_quirk(device, max_level, level_old);
 999         if (result)
1000                 goto out_free_levels;
1001         /*
1002          * cap._BQC may get cleared due to _BQC is found to be broken
1003          * in acpi_video_bqc_quirk, so check again here.
1004          */
1005         if (!device->cap._BQC)
1006                 goto set_level;
1007
1008         level = acpi_video_bqc_value_to_level(device, level_old);
1009         /*
1010          * On some buggy laptops, _BQC returns an uninitialized
1011          * value when invoked for the first time, i.e.
1012          * level_old is invalid (no matter whether it's a level
1013          * or an index). Set the backlight to max_level in this case.
1014          */
1015         for (i = ACPI_VIDEO_FIRST_LEVEL; i < br->count; i++)
1016                 if (level == br->levels[i])
1017                         break;
1018         if (i == br->count || !level)
1019                 level = max_level;
1020
1021 set_level:
1022         result = acpi_video_device_lcd_set_level(device, level);
1023         if (result)
1024                 goto out_free_levels;
1025
1026         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1027                           "found %d brightness levels\n",
1028                           br->count - ACPI_VIDEO_FIRST_LEVEL));
1029         return 0;
1030
1031 out_free_levels:
1032         kfree(br->levels);
1033         kfree(br);
1034         device->brightness = NULL;
1035         return result;
1036 }
1037
1038 /*
1039  *  Arg:
1040  *      device  : video output device (LCD, CRT, ..)
1041  *
1042  *  Return Value:
1043  *      None
1044  *
1045  *  Find out all required AML methods defined under the output
1046  *  device.
1047  */
1048
1049 static void acpi_video_device_find_cap(struct acpi_video_device *device)
1050 {
1051         if (acpi_has_method(device->dev->handle, "_ADR"))
1052                 device->cap._ADR = 1;
1053         if (acpi_has_method(device->dev->handle, "_BCL"))
1054                 device->cap._BCL = 1;
1055         if (acpi_has_method(device->dev->handle, "_BCM"))
1056                 device->cap._BCM = 1;
1057         if (acpi_has_method(device->dev->handle, "_BQC")) {
1058                 device->cap._BQC = 1;
1059         } else if (acpi_has_method(device->dev->handle, "_BCQ")) {
1060                 printk(KERN_WARNING FW_BUG "_BCQ is used instead of _BQC\n");
1061                 device->cap._BCQ = 1;
1062         }
1063
1064         if (acpi_has_method(device->dev->handle, "_DDC"))
1065                 device->cap._DDC = 1;
1066 }
1067
1068 /*
1069  *  Arg:
1070  *      device  : video output device (VGA)
1071  *
1072  *  Return Value:
1073  *      None
1074  *
1075  *  Find out all required AML methods defined under the video bus device.
1076  */
1077
1078 static void acpi_video_bus_find_cap(struct acpi_video_bus *video)
1079 {
1080         if (acpi_has_method(video->device->handle, "_DOS"))
1081                 video->cap._DOS = 1;
1082         if (acpi_has_method(video->device->handle, "_DOD"))
1083                 video->cap._DOD = 1;
1084         if (acpi_has_method(video->device->handle, "_ROM"))
1085                 video->cap._ROM = 1;
1086         if (acpi_has_method(video->device->handle, "_GPD"))
1087                 video->cap._GPD = 1;
1088         if (acpi_has_method(video->device->handle, "_SPD"))
1089                 video->cap._SPD = 1;
1090         if (acpi_has_method(video->device->handle, "_VPO"))
1091                 video->cap._VPO = 1;
1092 }
1093
1094 /*
1095  * Check whether the video bus device has required AML method to
1096  * support the desired features
1097  */
1098
1099 static int acpi_video_bus_check(struct acpi_video_bus *video)
1100 {
1101         acpi_status status = -ENOENT;
1102         struct pci_dev *dev;
1103
1104         if (!video)
1105                 return -EINVAL;
1106
1107         dev = acpi_get_pci_dev(video->device->handle);
1108         if (!dev)
1109                 return -ENODEV;
1110         pci_dev_put(dev);
1111
1112         /*
1113          * Since there is no HID, CID and so on for VGA driver, we have
1114          * to check well known required nodes.
1115          */
1116
1117         /* Does this device support video switching? */
1118         if (video->cap._DOS || video->cap._DOD) {
1119                 if (!video->cap._DOS) {
1120                         printk(KERN_WARNING FW_BUG
1121                                 "ACPI(%s) defines _DOD but not _DOS\n",
1122                                 acpi_device_bid(video->device));
1123                 }
1124                 video->flags.multihead = 1;
1125                 status = 0;
1126         }
1127
1128         /* Does this device support retrieving a video ROM? */
1129         if (video->cap._ROM) {
1130                 video->flags.rom = 1;
1131                 status = 0;
1132         }
1133
1134         /* Does this device support configuring which video device to POST? */
1135         if (video->cap._GPD && video->cap._SPD && video->cap._VPO) {
1136                 video->flags.post = 1;
1137                 status = 0;
1138         }
1139
1140         return status;
1141 }
1142
1143 /*
1144  * --------------------------------------------------------------------------
1145  *                               Driver Interface
1146  * --------------------------------------------------------------------------
1147  */
1148
1149 /* device interface */
1150 static struct acpi_video_device_attrib *
1151 acpi_video_get_device_attr(struct acpi_video_bus *video, 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.attrib;
1160         }
1161
1162         return NULL;
1163 }
1164
1165 static int
1166 acpi_video_get_device_type(struct acpi_video_bus *video,
1167                            unsigned long device_id)
1168 {
1169         struct acpi_video_enumerated_device *ids;
1170         int i;
1171
1172         for (i = 0; i < video->attached_count; i++) {
1173                 ids = &video->attached_array[i];
1174                 if ((ids->value.int_val & 0xffff) == device_id)
1175                         return ids->value.int_val;
1176         }
1177
1178         return 0;
1179 }
1180
1181 static int
1182 acpi_video_bus_get_one_device(struct acpi_device *device,
1183                               struct acpi_video_bus *video)
1184 {
1185         unsigned long long device_id;
1186         int status, device_type;
1187         struct acpi_video_device *data;
1188         struct acpi_video_device_attrib *attribute;
1189
1190         status =
1191             acpi_evaluate_integer(device->handle, "_ADR", NULL, &device_id);
1192         /* Some device omits _ADR, we skip them instead of fail */
1193         if (ACPI_FAILURE(status))
1194                 return 0;
1195
1196         data = kzalloc(sizeof(struct acpi_video_device), GFP_KERNEL);
1197         if (!data)
1198                 return -ENOMEM;
1199
1200         strcpy(acpi_device_name(device), ACPI_VIDEO_DEVICE_NAME);
1201         strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
1202         device->driver_data = data;
1203
1204         data->device_id = device_id;
1205         data->video = video;
1206         data->dev = device;
1207         INIT_DELAYED_WORK(&data->switch_brightness_work,
1208                           acpi_video_switch_brightness);
1209
1210         attribute = acpi_video_get_device_attr(video, device_id);
1211
1212         if (attribute && (attribute->device_id_scheme || device_id_scheme)) {
1213                 switch (attribute->display_type) {
1214                 case ACPI_VIDEO_DISPLAY_CRT:
1215                         data->flags.crt = 1;
1216                         break;
1217                 case ACPI_VIDEO_DISPLAY_TV:
1218                         data->flags.tvout = 1;
1219                         break;
1220                 case ACPI_VIDEO_DISPLAY_DVI:
1221                         data->flags.dvi = 1;
1222                         break;
1223                 case ACPI_VIDEO_DISPLAY_LCD:
1224                         data->flags.lcd = 1;
1225                         break;
1226                 default:
1227                         data->flags.unknown = 1;
1228                         break;
1229                 }
1230                 if (attribute->bios_can_detect)
1231                         data->flags.bios = 1;
1232         } else {
1233                 /* Check for legacy IDs */
1234                 device_type = acpi_video_get_device_type(video, device_id);
1235                 /* Ignore bits 16 and 18-20 */
1236                 switch (device_type & 0xffe2ffff) {
1237                 case ACPI_VIDEO_DISPLAY_LEGACY_MONITOR:
1238                         data->flags.crt = 1;
1239                         break;
1240                 case ACPI_VIDEO_DISPLAY_LEGACY_PANEL:
1241                         data->flags.lcd = 1;
1242                         break;
1243                 case ACPI_VIDEO_DISPLAY_LEGACY_TV:
1244                         data->flags.tvout = 1;
1245                         break;
1246                 default:
1247                         data->flags.unknown = 1;
1248                 }
1249         }
1250
1251         acpi_video_device_bind(video, data);
1252         acpi_video_device_find_cap(data);
1253
1254         mutex_lock(&video->device_list_lock);
1255         list_add_tail(&data->entry, &video->video_device_list);
1256         mutex_unlock(&video->device_list_lock);
1257
1258         return status;
1259 }
1260
1261 /*
1262  *  Arg:
1263  *      video   : video bus device
1264  *
1265  *  Return:
1266  *      none
1267  *
1268  *  Enumerate the video device list of the video bus,
1269  *  bind the ids with the corresponding video devices
1270  *  under the video bus.
1271  */
1272
1273 static void acpi_video_device_rebind(struct acpi_video_bus *video)
1274 {
1275         struct acpi_video_device *dev;
1276
1277         mutex_lock(&video->device_list_lock);
1278
1279         list_for_each_entry(dev, &video->video_device_list, entry)
1280                 acpi_video_device_bind(video, dev);
1281
1282         mutex_unlock(&video->device_list_lock);
1283 }
1284
1285 /*
1286  *  Arg:
1287  *      video   : video bus device
1288  *      device  : video output device under the video
1289  *              bus
1290  *
1291  *  Return:
1292  *      none
1293  *
1294  *  Bind the ids with the corresponding video devices
1295  *  under the video bus.
1296  */
1297
1298 static void
1299 acpi_video_device_bind(struct acpi_video_bus *video,
1300                        struct acpi_video_device *device)
1301 {
1302         struct acpi_video_enumerated_device *ids;
1303         int i;
1304
1305         for (i = 0; i < video->attached_count; i++) {
1306                 ids = &video->attached_array[i];
1307                 if (device->device_id == (ids->value.int_val & 0xffff)) {
1308                         ids->bind_info = device;
1309                         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "device_bind %d\n", i));
1310                 }
1311         }
1312 }
1313
1314 static bool acpi_video_device_in_dod(struct acpi_video_device *device)
1315 {
1316         struct acpi_video_bus *video = device->video;
1317         int i;
1318
1319         /*
1320          * If we have a broken _DOD or we have more than 8 output devices
1321          * under the graphics controller node that we can't proper deal with
1322          * in the operation region code currently, no need to test.
1323          */
1324         if (!video->attached_count || video->child_count > 8)
1325                 return true;
1326
1327         for (i = 0; i < video->attached_count; i++) {
1328                 if ((video->attached_array[i].value.int_val & 0xfff) ==
1329                     (device->device_id & 0xfff))
1330                         return true;
1331         }
1332
1333         return false;
1334 }
1335
1336 /*
1337  *  Arg:
1338  *      video   : video bus device
1339  *
1340  *  Return:
1341  *      < 0     : error
1342  *
1343  *  Call _DOD to enumerate all devices attached to display adapter
1344  *
1345  */
1346
1347 static int acpi_video_device_enumerate(struct acpi_video_bus *video)
1348 {
1349         int status;
1350         int count;
1351         int i;
1352         struct acpi_video_enumerated_device *active_list;
1353         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1354         union acpi_object *dod = NULL;
1355         union acpi_object *obj;
1356
1357         if (!video->cap._DOD)
1358                 return AE_NOT_EXIST;
1359
1360         status = acpi_evaluate_object(video->device->handle, "_DOD", NULL, &buffer);
1361         if (!ACPI_SUCCESS(status)) {
1362                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _DOD"));
1363                 return status;
1364         }
1365
1366         dod = buffer.pointer;
1367         if (!dod || (dod->type != ACPI_TYPE_PACKAGE)) {
1368                 ACPI_EXCEPTION((AE_INFO, status, "Invalid _DOD data"));
1369                 status = -EFAULT;
1370                 goto out;
1371         }
1372
1373         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d video heads in _DOD\n",
1374                           dod->package.count));
1375
1376         active_list = kcalloc(1 + dod->package.count,
1377                               sizeof(struct acpi_video_enumerated_device),
1378                               GFP_KERNEL);
1379         if (!active_list) {
1380                 status = -ENOMEM;
1381                 goto out;
1382         }
1383
1384         count = 0;
1385         for (i = 0; i < dod->package.count; i++) {
1386                 obj = &dod->package.elements[i];
1387
1388                 if (obj->type != ACPI_TYPE_INTEGER) {
1389                         printk(KERN_ERR PREFIX
1390                                 "Invalid _DOD data in element %d\n", i);
1391                         continue;
1392                 }
1393
1394                 active_list[count].value.int_val = obj->integer.value;
1395                 active_list[count].bind_info = NULL;
1396                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "dod element[%d] = %d\n", i,
1397                                   (int)obj->integer.value));
1398                 count++;
1399         }
1400
1401         kfree(video->attached_array);
1402
1403         video->attached_array = active_list;
1404         video->attached_count = count;
1405
1406 out:
1407         kfree(buffer.pointer);
1408         return status;
1409 }
1410
1411 static int
1412 acpi_video_get_next_level(struct acpi_video_device *device,
1413                           u32 level_current, u32 event)
1414 {
1415         int min, max, min_above, max_below, i, l, delta = 255;
1416         max = max_below = 0;
1417         min = min_above = 255;
1418         /* Find closest level to level_current */
1419         for (i = ACPI_VIDEO_FIRST_LEVEL; i < device->brightness->count; i++) {
1420                 l = device->brightness->levels[i];
1421                 if (abs(l - level_current) < abs(delta)) {
1422                         delta = l - level_current;
1423                         if (!delta)
1424                                 break;
1425                 }
1426         }
1427         /* Ajust level_current to closest available level */
1428         level_current += delta;
1429         for (i = ACPI_VIDEO_FIRST_LEVEL; i < device->brightness->count; i++) {
1430                 l = device->brightness->levels[i];
1431                 if (l < min)
1432                         min = l;
1433                 if (l > max)
1434                         max = l;
1435                 if (l < min_above && l > level_current)
1436                         min_above = l;
1437                 if (l > max_below && l < level_current)
1438                         max_below = l;
1439         }
1440
1441         switch (event) {
1442         case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:
1443                 return (level_current < max) ? min_above : min;
1444         case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:
1445                 return (level_current < max) ? min_above : max;
1446         case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:
1447                 return (level_current > min) ? max_below : min;
1448         case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS:
1449         case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:
1450                 return 0;
1451         default:
1452                 return level_current;
1453         }
1454 }
1455
1456 static void
1457 acpi_video_switch_brightness(struct work_struct *work)
1458 {
1459         struct acpi_video_device *device = container_of(to_delayed_work(work),
1460                              struct acpi_video_device, switch_brightness_work);
1461         unsigned long long level_current, level_next;
1462         int event = device->switch_brightness_event;
1463         int result = -EINVAL;
1464
1465         /* no warning message if acpi_backlight=vendor or a quirk is used */
1466         if (!device->backlight)
1467                 return;
1468
1469         if (!device->brightness)
1470                 goto out;
1471
1472         result = acpi_video_device_lcd_get_level_current(device,
1473                                                          &level_current,
1474                                                          false);
1475         if (result)
1476                 goto out;
1477
1478         level_next = acpi_video_get_next_level(device, level_current, event);
1479
1480         result = acpi_video_device_lcd_set_level(device, level_next);
1481
1482         if (!result)
1483                 backlight_force_update(device->backlight,
1484                                        BACKLIGHT_UPDATE_HOTKEY);
1485
1486 out:
1487         if (result)
1488                 printk(KERN_ERR PREFIX "Failed to switch the brightness\n");
1489 }
1490
1491 int acpi_video_get_edid(struct acpi_device *device, int type, int device_id,
1492                         void **edid)
1493 {
1494         struct acpi_video_bus *video;
1495         struct acpi_video_device *video_device;
1496         union acpi_object *buffer = NULL;
1497         acpi_status status;
1498         int i, length;
1499
1500         if (!device || !acpi_driver_data(device))
1501                 return -EINVAL;
1502
1503         video = acpi_driver_data(device);
1504
1505         for (i = 0; i < video->attached_count; i++) {
1506                 video_device = video->attached_array[i].bind_info;
1507                 length = 256;
1508
1509                 if (!video_device)
1510                         continue;
1511
1512                 if (!video_device->cap._DDC)
1513                         continue;
1514
1515                 if (type) {
1516                         switch (type) {
1517                         case ACPI_VIDEO_DISPLAY_CRT:
1518                                 if (!video_device->flags.crt)
1519                                         continue;
1520                                 break;
1521                         case ACPI_VIDEO_DISPLAY_TV:
1522                                 if (!video_device->flags.tvout)
1523                                         continue;
1524                                 break;
1525                         case ACPI_VIDEO_DISPLAY_DVI:
1526                                 if (!video_device->flags.dvi)
1527                                         continue;
1528                                 break;
1529                         case ACPI_VIDEO_DISPLAY_LCD:
1530                                 if (!video_device->flags.lcd)
1531                                         continue;
1532                                 break;
1533                         }
1534                 } else if (video_device->device_id != device_id) {
1535                         continue;
1536                 }
1537
1538                 status = acpi_video_device_EDID(video_device, &buffer, length);
1539
1540                 if (ACPI_FAILURE(status) || !buffer ||
1541                     buffer->type != ACPI_TYPE_BUFFER) {
1542                         length = 128;
1543                         status = acpi_video_device_EDID(video_device, &buffer,
1544                                                         length);
1545                         if (ACPI_FAILURE(status) || !buffer ||
1546                             buffer->type != ACPI_TYPE_BUFFER) {
1547                                 continue;
1548                         }
1549                 }
1550
1551                 *edid = buffer->buffer.pointer;
1552                 return length;
1553         }
1554
1555         return -ENODEV;
1556 }
1557 EXPORT_SYMBOL(acpi_video_get_edid);
1558
1559 static int
1560 acpi_video_bus_get_devices(struct acpi_video_bus *video,
1561                            struct acpi_device *device)
1562 {
1563         int status = 0;
1564         struct acpi_device *dev;
1565
1566         /*
1567          * There are systems where video module known to work fine regardless
1568          * of broken _DOD and ignoring returned value here doesn't cause
1569          * any issues later.
1570          */
1571         acpi_video_device_enumerate(video);
1572
1573         list_for_each_entry(dev, &device->children, node) {
1574
1575                 status = acpi_video_bus_get_one_device(dev, video);
1576                 if (status) {
1577                         dev_err(&dev->dev, "Can't attach device\n");
1578                         break;
1579                 }
1580                 video->child_count++;
1581         }
1582         return status;
1583 }
1584
1585 /* acpi_video interface */
1586
1587 /*
1588  * Win8 requires setting bit2 of _DOS to let firmware know it shouldn't
1589  * preform any automatic brightness change on receiving a notification.
1590  */
1591 static int acpi_video_bus_start_devices(struct acpi_video_bus *video)
1592 {
1593         return acpi_video_bus_DOS(video, 0,
1594                                   acpi_osi_is_win8() ? 1 : 0);
1595 }
1596
1597 static int acpi_video_bus_stop_devices(struct acpi_video_bus *video)
1598 {
1599         return acpi_video_bus_DOS(video, 0,
1600                                   acpi_osi_is_win8() ? 0 : 1);
1601 }
1602
1603 static void acpi_video_bus_notify(struct acpi_device *device, u32 event)
1604 {
1605         struct acpi_video_bus *video = acpi_driver_data(device);
1606         struct input_dev *input;
1607         int keycode = 0;
1608
1609         if (!video || !video->input)
1610                 return;
1611
1612         input = video->input;
1613
1614         switch (event) {
1615         case ACPI_VIDEO_NOTIFY_SWITCH:  /* User requested a switch,
1616                                          * most likely via hotkey. */
1617                 keycode = KEY_SWITCHVIDEOMODE;
1618                 break;
1619
1620         case ACPI_VIDEO_NOTIFY_PROBE:   /* User plugged in or removed a video
1621                                          * connector. */
1622                 acpi_video_device_enumerate(video);
1623                 acpi_video_device_rebind(video);
1624                 keycode = KEY_SWITCHVIDEOMODE;
1625                 break;
1626
1627         case ACPI_VIDEO_NOTIFY_CYCLE:   /* Cycle Display output hotkey pressed. */
1628                 keycode = KEY_SWITCHVIDEOMODE;
1629                 break;
1630         case ACPI_VIDEO_NOTIFY_NEXT_OUTPUT:     /* Next Display output hotkey pressed. */
1631                 keycode = KEY_VIDEO_NEXT;
1632                 break;
1633         case ACPI_VIDEO_NOTIFY_PREV_OUTPUT:     /* previous Display output hotkey pressed. */
1634                 keycode = KEY_VIDEO_PREV;
1635                 break;
1636
1637         default:
1638                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1639                                   "Unsupported event [0x%x]\n", event));
1640                 break;
1641         }
1642
1643         if (acpi_notifier_call_chain(device, event, 0))
1644                 /* Something vetoed the keypress. */
1645                 keycode = 0;
1646
1647         if (keycode && (report_key_events & REPORT_OUTPUT_KEY_EVENTS)) {
1648                 input_report_key(input, keycode, 1);
1649                 input_sync(input);
1650                 input_report_key(input, keycode, 0);
1651                 input_sync(input);
1652         }
1653
1654         return;
1655 }
1656
1657 static void brightness_switch_event(struct acpi_video_device *video_device,
1658                                     u32 event)
1659 {
1660         if (!brightness_switch_enabled)
1661                 return;
1662
1663         video_device->switch_brightness_event = event;
1664         schedule_delayed_work(&video_device->switch_brightness_work, HZ / 10);
1665 }
1666
1667 static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data)
1668 {
1669         struct acpi_video_device *video_device = data;
1670         struct acpi_device *device = NULL;
1671         struct acpi_video_bus *bus;
1672         struct input_dev *input;
1673         int keycode = 0;
1674
1675         if (!video_device)
1676                 return;
1677
1678         device = video_device->dev;
1679         bus = video_device->video;
1680         input = bus->input;
1681
1682         if (hw_changes_brightness > 0) {
1683                 if (video_device->backlight)
1684                         backlight_force_update(video_device->backlight,
1685                                                BACKLIGHT_UPDATE_HOTKEY);
1686                 acpi_notifier_call_chain(device, event, 0);
1687                 return;
1688         }
1689
1690         switch (event) {
1691         case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:        /* Cycle brightness */
1692                 brightness_switch_event(video_device, event);
1693                 keycode = KEY_BRIGHTNESS_CYCLE;
1694                 break;
1695         case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:  /* Increase brightness */
1696                 brightness_switch_event(video_device, event);
1697                 keycode = KEY_BRIGHTNESSUP;
1698                 break;
1699         case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:  /* Decrease brightness */
1700                 brightness_switch_event(video_device, event);
1701                 keycode = KEY_BRIGHTNESSDOWN;
1702                 break;
1703         case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS: /* zero brightness */
1704                 brightness_switch_event(video_device, event);
1705                 keycode = KEY_BRIGHTNESS_ZERO;
1706                 break;
1707         case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:     /* display device off */
1708                 brightness_switch_event(video_device, event);
1709                 keycode = KEY_DISPLAY_OFF;
1710                 break;
1711         default:
1712                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1713                                   "Unsupported event [0x%x]\n", event));
1714                 break;
1715         }
1716
1717         acpi_notifier_call_chain(device, event, 0);
1718
1719         if (keycode && (report_key_events & REPORT_BRIGHTNESS_KEY_EVENTS)) {
1720                 input_report_key(input, keycode, 1);
1721                 input_sync(input);
1722                 input_report_key(input, keycode, 0);
1723                 input_sync(input);
1724         }
1725
1726         return;
1727 }
1728
1729 static int acpi_video_resume(struct notifier_block *nb,
1730                                 unsigned long val, void *ign)
1731 {
1732         struct acpi_video_bus *video;
1733         struct acpi_video_device *video_device;
1734         int i;
1735
1736         switch (val) {
1737         case PM_HIBERNATION_PREPARE:
1738         case PM_SUSPEND_PREPARE:
1739         case PM_RESTORE_PREPARE:
1740                 return NOTIFY_DONE;
1741         }
1742
1743         video = container_of(nb, struct acpi_video_bus, pm_nb);
1744
1745         dev_info(&video->device->dev, "Restoring backlight state\n");
1746
1747         for (i = 0; i < video->attached_count; i++) {
1748                 video_device = video->attached_array[i].bind_info;
1749                 if (video_device && video_device->brightness)
1750                         acpi_video_device_lcd_set_level(video_device,
1751                                         video_device->brightness->curr);
1752         }
1753
1754         return NOTIFY_OK;
1755 }
1756
1757 static acpi_status
1758 acpi_video_bus_match(acpi_handle handle, u32 level, void *context,
1759                         void **return_value)
1760 {
1761         struct acpi_device *device = context;
1762         struct acpi_device *sibling;
1763         int result;
1764
1765         if (handle == device->handle)
1766                 return AE_CTRL_TERMINATE;
1767
1768         result = acpi_bus_get_device(handle, &sibling);
1769         if (result)
1770                 return AE_OK;
1771
1772         if (!strcmp(acpi_device_name(sibling), ACPI_VIDEO_BUS_NAME))
1773                         return AE_ALREADY_EXISTS;
1774
1775         return AE_OK;
1776 }
1777
1778 static void acpi_video_dev_register_backlight(struct acpi_video_device *device)
1779 {
1780         struct backlight_properties props;
1781         struct pci_dev *pdev;
1782         acpi_handle acpi_parent;
1783         struct device *parent = NULL;
1784         int result;
1785         static int count;
1786         char *name;
1787
1788         result = acpi_video_init_brightness(device);
1789         if (result)
1790                 return;
1791
1792         if (disable_backlight_sysfs_if > 0)
1793                 return;
1794
1795         name = kasprintf(GFP_KERNEL, "acpi_video%d", count);
1796         if (!name)
1797                 return;
1798         count++;
1799
1800         acpi_get_parent(device->dev->handle, &acpi_parent);
1801
1802         pdev = acpi_get_pci_dev(acpi_parent);
1803         if (pdev) {
1804                 parent = &pdev->dev;
1805                 pci_dev_put(pdev);
1806         }
1807
1808         memset(&props, 0, sizeof(struct backlight_properties));
1809         props.type = BACKLIGHT_FIRMWARE;
1810         props.max_brightness =
1811                 device->brightness->count - ACPI_VIDEO_FIRST_LEVEL - 1;
1812         device->backlight = backlight_device_register(name,
1813                                                       parent,
1814                                                       device,
1815                                                       &acpi_backlight_ops,
1816                                                       &props);
1817         kfree(name);
1818         if (IS_ERR(device->backlight)) {
1819                 device->backlight = NULL;
1820                 return;
1821         }
1822
1823         /*
1824          * Save current brightness level in case we have to restore it
1825          * before acpi_video_device_lcd_set_level() is called next time.
1826          */
1827         device->backlight->props.brightness =
1828                         acpi_video_get_brightness(device->backlight);
1829
1830         device->cooling_dev = thermal_cooling_device_register("LCD",
1831                                 device->dev, &video_cooling_ops);
1832         if (IS_ERR(device->cooling_dev)) {
1833                 /*
1834                  * Set cooling_dev to NULL so we don't crash trying to free it.
1835                  * Also, why the hell we are returning early and not attempt to
1836                  * register video output if cooling device registration failed?
1837                  * -- dtor
1838                  */
1839                 device->cooling_dev = NULL;
1840                 return;
1841         }
1842
1843         dev_info(&device->dev->dev, "registered as cooling_device%d\n",
1844                  device->cooling_dev->id);
1845         result = sysfs_create_link(&device->dev->dev.kobj,
1846                         &device->cooling_dev->device.kobj,
1847                         "thermal_cooling");
1848         if (result)
1849                 printk(KERN_ERR PREFIX "Create sysfs link\n");
1850         result = sysfs_create_link(&device->cooling_dev->device.kobj,
1851                         &device->dev->dev.kobj, "device");
1852         if (result)
1853                 printk(KERN_ERR PREFIX "Create sysfs link\n");
1854 }
1855
1856 static void acpi_video_run_bcl_for_osi(struct acpi_video_bus *video)
1857 {
1858         struct acpi_video_device *dev;
1859         union acpi_object *levels;
1860
1861         mutex_lock(&video->device_list_lock);
1862         list_for_each_entry(dev, &video->video_device_list, entry) {
1863                 if (!acpi_video_device_lcd_query_levels(dev->dev->handle, &levels))
1864                         kfree(levels);
1865         }
1866         mutex_unlock(&video->device_list_lock);
1867 }
1868
1869 static bool acpi_video_should_register_backlight(struct acpi_video_device *dev)
1870 {
1871         /*
1872          * Do not create backlight device for video output
1873          * device that is not in the enumerated list.
1874          */
1875         if (!acpi_video_device_in_dod(dev)) {
1876                 dev_dbg(&dev->dev->dev, "not in _DOD list, ignore\n");
1877                 return false;
1878         }
1879
1880         if (only_lcd)
1881                 return dev->flags.lcd;
1882         return true;
1883 }
1884
1885 static int acpi_video_bus_register_backlight(struct acpi_video_bus *video)
1886 {
1887         struct acpi_video_device *dev;
1888
1889         if (video->backlight_registered)
1890                 return 0;
1891
1892         acpi_video_run_bcl_for_osi(video);
1893
1894         if (acpi_video_get_backlight_type() != acpi_backlight_video)
1895                 return 0;
1896
1897         mutex_lock(&video->device_list_lock);
1898         list_for_each_entry(dev, &video->video_device_list, entry) {
1899                 if (acpi_video_should_register_backlight(dev))
1900                         acpi_video_dev_register_backlight(dev);
1901         }
1902         mutex_unlock(&video->device_list_lock);
1903
1904         video->backlight_registered = true;
1905
1906         video->pm_nb.notifier_call = acpi_video_resume;
1907         video->pm_nb.priority = 0;
1908         return register_pm_notifier(&video->pm_nb);
1909 }
1910
1911 static void acpi_video_dev_unregister_backlight(struct acpi_video_device *device)
1912 {
1913         if (device->backlight) {
1914                 backlight_device_unregister(device->backlight);
1915                 device->backlight = NULL;
1916         }
1917         if (device->brightness) {
1918                 kfree(device->brightness->levels);
1919                 kfree(device->brightness);
1920                 device->brightness = NULL;
1921         }
1922         if (device->cooling_dev) {
1923                 sysfs_remove_link(&device->dev->dev.kobj, "thermal_cooling");
1924                 sysfs_remove_link(&device->cooling_dev->device.kobj, "device");
1925                 thermal_cooling_device_unregister(device->cooling_dev);
1926                 device->cooling_dev = NULL;
1927         }
1928 }
1929
1930 static int acpi_video_bus_unregister_backlight(struct acpi_video_bus *video)
1931 {
1932         struct acpi_video_device *dev;
1933         int error;
1934
1935         if (!video->backlight_registered)
1936                 return 0;
1937
1938         error = unregister_pm_notifier(&video->pm_nb);
1939
1940         mutex_lock(&video->device_list_lock);
1941         list_for_each_entry(dev, &video->video_device_list, entry)
1942                 acpi_video_dev_unregister_backlight(dev);
1943         mutex_unlock(&video->device_list_lock);
1944
1945         video->backlight_registered = false;
1946
1947         return error;
1948 }
1949
1950 static void acpi_video_dev_add_notify_handler(struct acpi_video_device *device)
1951 {
1952         acpi_status status;
1953         struct acpi_device *adev = device->dev;
1954
1955         status = acpi_install_notify_handler(adev->handle, ACPI_DEVICE_NOTIFY,
1956                                              acpi_video_device_notify, device);
1957         if (ACPI_FAILURE(status))
1958                 dev_err(&adev->dev, "Error installing notify handler\n");
1959         else
1960                 device->flags.notify = 1;
1961 }
1962
1963 static int acpi_video_bus_add_notify_handler(struct acpi_video_bus *video)
1964 {
1965         struct input_dev *input;
1966         struct acpi_video_device *dev;
1967         int error;
1968
1969         video->input = input = input_allocate_device();
1970         if (!input) {
1971                 error = -ENOMEM;
1972                 goto out;
1973         }
1974
1975         error = acpi_video_bus_start_devices(video);
1976         if (error)
1977                 goto err_free_input;
1978
1979         snprintf(video->phys, sizeof(video->phys),
1980                         "%s/video/input0", acpi_device_hid(video->device));
1981
1982         input->name = acpi_device_name(video->device);
1983         input->phys = video->phys;
1984         input->id.bustype = BUS_HOST;
1985         input->id.product = 0x06;
1986         input->dev.parent = &video->device->dev;
1987         input->evbit[0] = BIT(EV_KEY);
1988         set_bit(KEY_SWITCHVIDEOMODE, input->keybit);
1989         set_bit(KEY_VIDEO_NEXT, input->keybit);
1990         set_bit(KEY_VIDEO_PREV, input->keybit);
1991         set_bit(KEY_BRIGHTNESS_CYCLE, input->keybit);
1992         set_bit(KEY_BRIGHTNESSUP, input->keybit);
1993         set_bit(KEY_BRIGHTNESSDOWN, input->keybit);
1994         set_bit(KEY_BRIGHTNESS_ZERO, input->keybit);
1995         set_bit(KEY_DISPLAY_OFF, input->keybit);
1996
1997         error = input_register_device(input);
1998         if (error)
1999                 goto err_stop_dev;
2000
2001         mutex_lock(&video->device_list_lock);
2002         list_for_each_entry(dev, &video->video_device_list, entry)
2003                 acpi_video_dev_add_notify_handler(dev);
2004         mutex_unlock(&video->device_list_lock);
2005
2006         return 0;
2007
2008 err_stop_dev:
2009         acpi_video_bus_stop_devices(video);
2010 err_free_input:
2011         input_free_device(input);
2012         video->input = NULL;
2013 out:
2014         return error;
2015 }
2016
2017 static void acpi_video_dev_remove_notify_handler(struct acpi_video_device *dev)
2018 {
2019         if (dev->flags.notify) {
2020                 acpi_remove_notify_handler(dev->dev->handle, ACPI_DEVICE_NOTIFY,
2021                                            acpi_video_device_notify);
2022                 dev->flags.notify = 0;
2023         }
2024 }
2025
2026 static void acpi_video_bus_remove_notify_handler(struct acpi_video_bus *video)
2027 {
2028         struct acpi_video_device *dev;
2029
2030         mutex_lock(&video->device_list_lock);
2031         list_for_each_entry(dev, &video->video_device_list, entry)
2032                 acpi_video_dev_remove_notify_handler(dev);
2033         mutex_unlock(&video->device_list_lock);
2034
2035         acpi_video_bus_stop_devices(video);
2036         input_unregister_device(video->input);
2037         video->input = NULL;
2038 }
2039
2040 static int acpi_video_bus_put_devices(struct acpi_video_bus *video)
2041 {
2042         struct acpi_video_device *dev, *next;
2043
2044         mutex_lock(&video->device_list_lock);
2045         list_for_each_entry_safe(dev, next, &video->video_device_list, entry) {
2046                 list_del(&dev->entry);
2047                 kfree(dev);
2048         }
2049         mutex_unlock(&video->device_list_lock);
2050
2051         return 0;
2052 }
2053
2054 static int instance;
2055
2056 static int acpi_video_bus_add(struct acpi_device *device)
2057 {
2058         struct acpi_video_bus *video;
2059         int error;
2060         acpi_status status;
2061
2062         status = acpi_walk_namespace(ACPI_TYPE_DEVICE,
2063                                 device->parent->handle, 1,
2064                                 acpi_video_bus_match, NULL,
2065                                 device, NULL);
2066         if (status == AE_ALREADY_EXISTS) {
2067                 printk(KERN_WARNING FW_BUG
2068                         "Duplicate ACPI video bus devices for the"
2069                         " same VGA controller, please try module "
2070                         "parameter \"video.allow_duplicates=1\""
2071                         "if the current driver doesn't work.\n");
2072                 if (!allow_duplicates)
2073                         return -ENODEV;
2074         }
2075
2076         video = kzalloc(sizeof(struct acpi_video_bus), GFP_KERNEL);
2077         if (!video)
2078                 return -ENOMEM;
2079
2080         /* a hack to fix the duplicate name "VID" problem on T61 */
2081         if (!strcmp(device->pnp.bus_id, "VID")) {
2082                 if (instance)
2083                         device->pnp.bus_id[3] = '0' + instance;
2084                 instance++;
2085         }
2086         /* a hack to fix the duplicate name "VGA" problem on Pa 3553 */
2087         if (!strcmp(device->pnp.bus_id, "VGA")) {
2088                 if (instance)
2089                         device->pnp.bus_id[3] = '0' + instance;
2090                 instance++;
2091         }
2092
2093         video->device = device;
2094         strcpy(acpi_device_name(device), ACPI_VIDEO_BUS_NAME);
2095         strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
2096         device->driver_data = video;
2097
2098         acpi_video_bus_find_cap(video);
2099         error = acpi_video_bus_check(video);
2100         if (error)
2101                 goto err_free_video;
2102
2103         mutex_init(&video->device_list_lock);
2104         INIT_LIST_HEAD(&video->video_device_list);
2105
2106         error = acpi_video_bus_get_devices(video, device);
2107         if (error)
2108                 goto err_put_video;
2109
2110         printk(KERN_INFO PREFIX "%s [%s] (multi-head: %s  rom: %s  post: %s)\n",
2111                ACPI_VIDEO_DEVICE_NAME, acpi_device_bid(device),
2112                video->flags.multihead ? "yes" : "no",
2113                video->flags.rom ? "yes" : "no",
2114                video->flags.post ? "yes" : "no");
2115         mutex_lock(&video_list_lock);
2116         list_add_tail(&video->entry, &video_bus_head);
2117         mutex_unlock(&video_list_lock);
2118
2119         acpi_video_bus_register_backlight(video);
2120         acpi_video_bus_add_notify_handler(video);
2121
2122         return 0;
2123
2124 err_put_video:
2125         acpi_video_bus_put_devices(video);
2126         kfree(video->attached_array);
2127 err_free_video:
2128         kfree(video);
2129         device->driver_data = NULL;
2130
2131         return error;
2132 }
2133
2134 static int acpi_video_bus_remove(struct acpi_device *device)
2135 {
2136         struct acpi_video_bus *video = NULL;
2137
2138
2139         if (!device || !acpi_driver_data(device))
2140                 return -EINVAL;
2141
2142         video = acpi_driver_data(device);
2143
2144         acpi_video_bus_remove_notify_handler(video);
2145         acpi_video_bus_unregister_backlight(video);
2146         acpi_video_bus_put_devices(video);
2147
2148         mutex_lock(&video_list_lock);
2149         list_del(&video->entry);
2150         mutex_unlock(&video_list_lock);
2151
2152         kfree(video->attached_array);
2153         kfree(video);
2154
2155         return 0;
2156 }
2157
2158 static int __init is_i740(struct pci_dev *dev)
2159 {
2160         if (dev->device == 0x00D1)
2161                 return 1;
2162         if (dev->device == 0x7000)
2163                 return 1;
2164         return 0;
2165 }
2166
2167 static int __init intel_opregion_present(void)
2168 {
2169         int opregion = 0;
2170         struct pci_dev *dev = NULL;
2171         u32 address;
2172
2173         for_each_pci_dev(dev) {
2174                 if ((dev->class >> 8) != PCI_CLASS_DISPLAY_VGA)
2175                         continue;
2176                 if (dev->vendor != PCI_VENDOR_ID_INTEL)
2177                         continue;
2178                 /* We don't want to poke around undefined i740 registers */
2179                 if (is_i740(dev))
2180                         continue;
2181                 pci_read_config_dword(dev, 0xfc, &address);
2182                 if (!address)
2183                         continue;
2184                 opregion = 1;
2185         }
2186         return opregion;
2187 }
2188
2189 /* Check if the chassis-type indicates there is no builtin LCD panel */
2190 static bool dmi_is_desktop(void)
2191 {
2192         const char *chassis_type;
2193         unsigned long type;
2194
2195         chassis_type = dmi_get_system_info(DMI_CHASSIS_TYPE);
2196         if (!chassis_type)
2197                 return false;
2198
2199         if (kstrtoul(chassis_type, 10, &type) != 0)
2200                 return false;
2201
2202         switch (type) {
2203         case 0x03: /* Desktop */
2204         case 0x04: /* Low Profile Desktop */
2205         case 0x05: /* Pizza Box */
2206         case 0x06: /* Mini Tower */
2207         case 0x07: /* Tower */
2208         case 0x10: /* Lunch Box */
2209         case 0x11: /* Main Server Chassis */
2210                 return true;
2211         }
2212
2213         return false;
2214 }
2215
2216 int acpi_video_register(void)
2217 {
2218         int ret = 0;
2219
2220         mutex_lock(&register_count_mutex);
2221         if (register_count) {
2222                 /*
2223                  * if the function of acpi_video_register is already called,
2224                  * don't register the acpi_vide_bus again and return no error.
2225                  */
2226                 goto leave;
2227         }
2228
2229         /*
2230          * We're seeing a lot of bogus backlight interfaces on newer machines
2231          * without a LCD such as desktops, servers and HDMI sticks. Checking
2232          * the lcd flag fixes this, so enable this on any machines which are
2233          * win8 ready (where we also prefer the native backlight driver, so
2234          * normally the acpi_video code should not register there anyways).
2235          */
2236         if (only_lcd == -1) {
2237                 if (dmi_is_desktop() && acpi_osi_is_win8())
2238                         only_lcd = true;
2239                 else
2240                         only_lcd = false;
2241         }
2242
2243         dmi_check_system(video_dmi_table);
2244
2245         ret = acpi_bus_register_driver(&acpi_video_bus);
2246         if (ret)
2247                 goto leave;
2248
2249         /*
2250          * When the acpi_video_bus is loaded successfully, increase
2251          * the counter reference.
2252          */
2253         register_count = 1;
2254
2255 leave:
2256         mutex_unlock(&register_count_mutex);
2257         return ret;
2258 }
2259 EXPORT_SYMBOL(acpi_video_register);
2260
2261 void acpi_video_unregister(void)
2262 {
2263         mutex_lock(&register_count_mutex);
2264         if (register_count) {
2265                 acpi_bus_unregister_driver(&acpi_video_bus);
2266                 register_count = 0;
2267         }
2268         mutex_unlock(&register_count_mutex);
2269 }
2270 EXPORT_SYMBOL(acpi_video_unregister);
2271
2272 void acpi_video_unregister_backlight(void)
2273 {
2274         struct acpi_video_bus *video;
2275
2276         mutex_lock(&register_count_mutex);
2277         if (register_count) {
2278                 mutex_lock(&video_list_lock);
2279                 list_for_each_entry(video, &video_bus_head, entry)
2280                         acpi_video_bus_unregister_backlight(video);
2281                 mutex_unlock(&video_list_lock);
2282         }
2283         mutex_unlock(&register_count_mutex);
2284 }
2285
2286 bool acpi_video_handles_brightness_key_presses(void)
2287 {
2288         bool have_video_busses;
2289
2290         mutex_lock(&video_list_lock);
2291         have_video_busses = !list_empty(&video_bus_head);
2292         mutex_unlock(&video_list_lock);
2293
2294         return have_video_busses &&
2295                (report_key_events & REPORT_BRIGHTNESS_KEY_EVENTS);
2296 }
2297 EXPORT_SYMBOL(acpi_video_handles_brightness_key_presses);
2298
2299 /*
2300  * This is kind of nasty. Hardware using Intel chipsets may require
2301  * the video opregion code to be run first in order to initialise
2302  * state before any ACPI video calls are made. To handle this we defer
2303  * registration of the video class until the opregion code has run.
2304  */
2305
2306 static int __init acpi_video_init(void)
2307 {
2308         /*
2309          * Let the module load even if ACPI is disabled (e.g. due to
2310          * a broken BIOS) so that i915.ko can still be loaded on such
2311          * old systems without an AcpiOpRegion.
2312          *
2313          * acpi_video_register() will report -ENODEV later as well due
2314          * to acpi_disabled when i915.ko tries to register itself afterwards.
2315          */
2316         if (acpi_disabled)
2317                 return 0;
2318
2319         if (intel_opregion_present())
2320                 return 0;
2321
2322         return acpi_video_register();
2323 }
2324
2325 static void __exit acpi_video_exit(void)
2326 {
2327         acpi_video_detect_exit();
2328         acpi_video_unregister();
2329
2330         return;
2331 }
2332
2333 module_init(acpi_video_init);
2334 module_exit(acpi_video_exit);