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 = 1;
  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((obj->package.count + ACPI_VIDEO_FIRST_LEVEL) *
 890                              sizeof(*br->levels), GFP_KERNEL);
 891         if (!br->levels) {
 892                 result = -ENOMEM;
 893                 goto out_free;
 894         }
 895
 896         for (i = 0; i < obj->package.count; i++) {
 897                 o = (union acpi_object *)&obj->package.elements[i];
 898                 if (o->type != ACPI_TYPE_INTEGER) {
 899                         printk(KERN_ERR PREFIX "Invalid data\n");
 900                         continue;
 901                 }
 902                 value = (u32) o->integer.value;
 903                 /* Skip duplicate entries */
 904                 if (count > ACPI_VIDEO_FIRST_LEVEL
 905                     && br->levels[count - 1] == value)
 906                         continue;
 907
 908                 br->levels[count] = value;
 909
 910                 if (br->levels[count] > max_level)
 911                         max_level = br->levels[count];
 912                 count++;
 913         }
 914
 915         /*
 916          * some buggy BIOS don't export the levels
 917          * when machine is on AC/Battery in _BCL package.
 918          * In this case, the first two elements in _BCL packages
 919          * are also supported brightness levels that OS should take care of.
 920          */
 921         for (i = ACPI_VIDEO_FIRST_LEVEL; i < count; i++) {
 922                 if (br->levels[i] == br->levels[ACPI_VIDEO_AC_LEVEL])
 923                         level_ac_battery++;
 924                 if (br->levels[i] == br->levels[ACPI_VIDEO_BATTERY_LEVEL])
 925                         level_ac_battery++;
 926         }
 927
 928         if (level_ac_battery < ACPI_VIDEO_FIRST_LEVEL) {
 929                 level_ac_battery = ACPI_VIDEO_FIRST_LEVEL - level_ac_battery;
 930                 br->flags._BCL_no_ac_battery_levels = 1;
 931                 for (i = (count - 1 + level_ac_battery);
 932                      i >= ACPI_VIDEO_FIRST_LEVEL; i--)
 933                         br->levels[i] = br->levels[i - level_ac_battery];
 934                 count += level_ac_battery;
 935         } else if (level_ac_battery > ACPI_VIDEO_FIRST_LEVEL)
 936                 ACPI_ERROR((AE_INFO, "Too many duplicates in _BCL package"));
 937
 938         /* Check if the _BCL package is in a reversed order */
 939         if (max_level == br->levels[ACPI_VIDEO_FIRST_LEVEL]) {
 940                 br->flags._BCL_reversed = 1;
 941                 sort(&br->levels[ACPI_VIDEO_FIRST_LEVEL],
 942                      count - ACPI_VIDEO_FIRST_LEVEL,
 943                      sizeof(br->levels[ACPI_VIDEO_FIRST_LEVEL]),
 944                      acpi_video_cmp_level, NULL);
 945         } else if (max_level != br->levels[count - 1])
 946                 ACPI_ERROR((AE_INFO,
 947                             "Found unordered _BCL package"));
 948
 949         br->count = count;
 950         *dev_br = br;
 951         if (pmax_level)
 952                 *pmax_level = max_level;
 953
 954 out:
 955         kfree(obj);
 956         return result;
 957 out_free:
 958         kfree(br);
 959         goto out;
 960 }
 961 EXPORT_SYMBOL(acpi_video_get_levels);
 962
 963 /*
 964  *  Arg:
 965  *      device  : video output device (LCD, CRT, ..)
 966  *
 967  *  Return Value:
 968  *      Maximum brightness level
 969  *
 970  *  Allocate and initialize device->brightness.
 971  */
 972
 973 static int
 974 acpi_video_init_brightness(struct acpi_video_device *device)
 975 {
 976         int i, max_level = 0;
 977         unsigned long long level, level_old;
 978         struct acpi_video_device_brightness *br = NULL;
 979         int result = -EINVAL;
 980
 981         result = acpi_video_get_levels(device->dev, &br, &max_level);
 982         if (result)
 983                 return result;
 984         device->brightness = br;
 985
 986         /* _BQC uses INDEX while _BCL uses VALUE in some laptops */
 987         br->curr = level = max_level;
 988
 989         if (!device->cap._BQC)
 990                 goto set_level;
 991
 992         result = acpi_video_device_lcd_get_level_current(device,
 993                                                          &level_old, true);
 994         if (result)
 995                 goto out_free_levels;
 996
 997         result = acpi_video_bqc_quirk(device, max_level, level_old);
 998         if (result)
 999                 goto out_free_levels;
1000         /*
1001          * cap._BQC may get cleared due to _BQC is found to be broken
1002          * in acpi_video_bqc_quirk, so check again here.
1003          */
1004         if (!device->cap._BQC)
1005                 goto set_level;
1006
1007         level = acpi_video_bqc_value_to_level(device, level_old);
1008         /*
1009          * On some buggy laptops, _BQC returns an uninitialized
1010          * value when invoked for the first time, i.e.
1011          * level_old is invalid (no matter whether it's a level
1012          * or an index). Set the backlight to max_level in this case.
1013          */
1014         for (i = ACPI_VIDEO_FIRST_LEVEL; i < br->count; i++)
1015                 if (level == br->levels[i])
1016                         break;
1017         if (i == br->count || !level)
1018                 level = max_level;
1019
1020 set_level:
1021         result = acpi_video_device_lcd_set_level(device, level);
1022         if (result)
1023                 goto out_free_levels;
1024
1025         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1026                           "found %d brightness levels\n",
1027                           br->count - ACPI_VIDEO_FIRST_LEVEL));
1028         return 0;
1029
1030 out_free_levels:
1031         kfree(br->levels);
1032         kfree(br);
1033         device->brightness = NULL;
1034         return result;
1035 }
1036
1037 /*
1038  *  Arg:
1039  *      device  : video output device (LCD, CRT, ..)
1040  *
1041  *  Return Value:
1042  *      None
1043  *
1044  *  Find out all required AML methods defined under the output
1045  *  device.
1046  */
1047
1048 static void acpi_video_device_find_cap(struct acpi_video_device *device)
1049 {
1050         if (acpi_has_method(device->dev->handle, "_ADR"))
1051                 device->cap._ADR = 1;
1052         if (acpi_has_method(device->dev->handle, "_BCL"))
1053                 device->cap._BCL = 1;
1054         if (acpi_has_method(device->dev->handle, "_BCM"))
1055                 device->cap._BCM = 1;
1056         if (acpi_has_method(device->dev->handle, "_BQC")) {
1057                 device->cap._BQC = 1;
1058         } else if (acpi_has_method(device->dev->handle, "_BCQ")) {
1059                 printk(KERN_WARNING FW_BUG "_BCQ is used instead of _BQC\n");
1060                 device->cap._BCQ = 1;
1061         }
1062
1063         if (acpi_has_method(device->dev->handle, "_DDC"))
1064                 device->cap._DDC = 1;
1065 }
1066
1067 /*
1068  *  Arg:
1069  *      device  : video output device (VGA)
1070  *
1071  *  Return Value:
1072  *      None
1073  *
1074  *  Find out all required AML methods defined under the video bus device.
1075  */
1076
1077 static void acpi_video_bus_find_cap(struct acpi_video_bus *video)
1078 {
1079         if (acpi_has_method(video->device->handle, "_DOS"))
1080                 video->cap._DOS = 1;
1081         if (acpi_has_method(video->device->handle, "_DOD"))
1082                 video->cap._DOD = 1;
1083         if (acpi_has_method(video->device->handle, "_ROM"))
1084                 video->cap._ROM = 1;
1085         if (acpi_has_method(video->device->handle, "_GPD"))
1086                 video->cap._GPD = 1;
1087         if (acpi_has_method(video->device->handle, "_SPD"))
1088                 video->cap._SPD = 1;
1089         if (acpi_has_method(video->device->handle, "_VPO"))
1090                 video->cap._VPO = 1;
1091 }
1092
1093 /*
1094  * Check whether the video bus device has required AML method to
1095  * support the desired features
1096  */
1097
1098 static int acpi_video_bus_check(struct acpi_video_bus *video)
1099 {
1100         acpi_status status = -ENOENT;
1101         struct pci_dev *dev;
1102
1103         if (!video)
1104                 return -EINVAL;
1105
1106         dev = acpi_get_pci_dev(video->device->handle);
1107         if (!dev)
1108                 return -ENODEV;
1109         pci_dev_put(dev);
1110
1111         /*
1112          * Since there is no HID, CID and so on for VGA driver, we have
1113          * to check well known required nodes.
1114          */
1115
1116         /* Does this device support video switching? */
1117         if (video->cap._DOS || video->cap._DOD) {
1118                 if (!video->cap._DOS) {
1119                         printk(KERN_WARNING FW_BUG
1120                                 "ACPI(%s) defines _DOD but not _DOS\n",
1121                                 acpi_device_bid(video->device));
1122                 }
1123                 video->flags.multihead = 1;
1124                 status = 0;
1125         }
1126
1127         /* Does this device support retrieving a video ROM? */
1128         if (video->cap._ROM) {
1129                 video->flags.rom = 1;
1130                 status = 0;
1131         }
1132
1133         /* Does this device support configuring which video device to POST? */
1134         if (video->cap._GPD && video->cap._SPD && video->cap._VPO) {
1135                 video->flags.post = 1;
1136                 status = 0;
1137         }
1138
1139         return status;
1140 }
1141
1142 /*
1143  * --------------------------------------------------------------------------
1144  *                               Driver Interface
1145  * --------------------------------------------------------------------------
1146  */
1147
1148 /* device interface */
1149 static struct acpi_video_device_attrib *
1150 acpi_video_get_device_attr(struct acpi_video_bus *video, unsigned long device_id)
1151 {
1152         struct acpi_video_enumerated_device *ids;
1153         int i;
1154
1155         for (i = 0; i < video->attached_count; i++) {
1156                 ids = &video->attached_array[i];
1157                 if ((ids->value.int_val & 0xffff) == device_id)
1158                         return &ids->value.attrib;
1159         }
1160
1161         return NULL;
1162 }
1163
1164 static int
1165 acpi_video_get_device_type(struct acpi_video_bus *video,
1166                            unsigned long device_id)
1167 {
1168         struct acpi_video_enumerated_device *ids;
1169         int i;
1170
1171         for (i = 0; i < video->attached_count; i++) {
1172                 ids = &video->attached_array[i];
1173                 if ((ids->value.int_val & 0xffff) == device_id)
1174                         return ids->value.int_val;
1175         }
1176
1177         return 0;
1178 }
1179
1180 static int
1181 acpi_video_bus_get_one_device(struct acpi_device *device,
1182                               struct acpi_video_bus *video)
1183 {
1184         unsigned long long device_id;
1185         int status, device_type;
1186         struct acpi_video_device *data;
1187         struct acpi_video_device_attrib *attribute;
1188
1189         status =
1190             acpi_evaluate_integer(device->handle, "_ADR", NULL, &device_id);
1191         /* Some device omits _ADR, we skip them instead of fail */
1192         if (ACPI_FAILURE(status))
1193                 return 0;
1194
1195         data = kzalloc(sizeof(struct acpi_video_device), GFP_KERNEL);
1196         if (!data)
1197                 return -ENOMEM;
1198
1199         strcpy(acpi_device_name(device), ACPI_VIDEO_DEVICE_NAME);
1200         strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
1201         device->driver_data = data;
1202
1203         data->device_id = device_id;
1204         data->video = video;
1205         data->dev = device;
1206         INIT_DELAYED_WORK(&data->switch_brightness_work,
1207                           acpi_video_switch_brightness);
1208
1209         attribute = acpi_video_get_device_attr(video, device_id);
1210
1211         if (attribute && (attribute->device_id_scheme || device_id_scheme)) {
1212                 switch (attribute->display_type) {
1213                 case ACPI_VIDEO_DISPLAY_CRT:
1214                         data->flags.crt = 1;
1215                         break;
1216                 case ACPI_VIDEO_DISPLAY_TV:
1217                         data->flags.tvout = 1;
1218                         break;
1219                 case ACPI_VIDEO_DISPLAY_DVI:
1220                         data->flags.dvi = 1;
1221                         break;
1222                 case ACPI_VIDEO_DISPLAY_LCD:
1223                         data->flags.lcd = 1;
1224                         break;
1225                 default:
1226                         data->flags.unknown = 1;
1227                         break;
1228                 }
1229                 if (attribute->bios_can_detect)
1230                         data->flags.bios = 1;
1231         } else {
1232                 /* Check for legacy IDs */
1233                 device_type = acpi_video_get_device_type(video, device_id);
1234                 /* Ignore bits 16 and 18-20 */
1235                 switch (device_type & 0xffe2ffff) {
1236                 case ACPI_VIDEO_DISPLAY_LEGACY_MONITOR:
1237                         data->flags.crt = 1;
1238                         break;
1239                 case ACPI_VIDEO_DISPLAY_LEGACY_PANEL:
1240                         data->flags.lcd = 1;
1241                         break;
1242                 case ACPI_VIDEO_DISPLAY_LEGACY_TV:
1243                         data->flags.tvout = 1;
1244                         break;
1245                 default:
1246                         data->flags.unknown = 1;
1247                 }
1248         }
1249
1250         acpi_video_device_bind(video, data);
1251         acpi_video_device_find_cap(data);
1252
1253         mutex_lock(&video->device_list_lock);
1254         list_add_tail(&data->entry, &video->video_device_list);
1255         mutex_unlock(&video->device_list_lock);
1256
1257         return status;
1258 }
1259
1260 /*
1261  *  Arg:
1262  *      video   : video bus device
1263  *
1264  *  Return:
1265  *      none
1266  *
1267  *  Enumerate the video device list of the video bus,
1268  *  bind the ids with the corresponding video devices
1269  *  under the video bus.
1270  */
1271
1272 static void acpi_video_device_rebind(struct acpi_video_bus *video)
1273 {
1274         struct acpi_video_device *dev;
1275
1276         mutex_lock(&video->device_list_lock);
1277
1278         list_for_each_entry(dev, &video->video_device_list, entry)
1279                 acpi_video_device_bind(video, dev);
1280
1281         mutex_unlock(&video->device_list_lock);
1282 }
1283
1284 /*
1285  *  Arg:
1286  *      video   : video bus device
1287  *      device  : video output device under the video
1288  *              bus
1289  *
1290  *  Return:
1291  *      none
1292  *
1293  *  Bind the ids with the corresponding video devices
1294  *  under the video bus.
1295  */
1296
1297 static void
1298 acpi_video_device_bind(struct acpi_video_bus *video,
1299                        struct acpi_video_device *device)
1300 {
1301         struct acpi_video_enumerated_device *ids;
1302         int i;
1303
1304         for (i = 0; i < video->attached_count; i++) {
1305                 ids = &video->attached_array[i];
1306                 if (device->device_id == (ids->value.int_val & 0xffff)) {
1307                         ids->bind_info = device;
1308                         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "device_bind %d\n", i));
1309                 }
1310         }
1311 }
1312
1313 static bool acpi_video_device_in_dod(struct acpi_video_device *device)
1314 {
1315         struct acpi_video_bus *video = device->video;
1316         int i;
1317
1318         /*
1319          * If we have a broken _DOD or we have more than 8 output devices
1320          * under the graphics controller node that we can't proper deal with
1321          * in the operation region code currently, no need to test.
1322          */
1323         if (!video->attached_count || video->child_count > 8)
1324                 return true;
1325
1326         for (i = 0; i < video->attached_count; i++) {
1327                 if ((video->attached_array[i].value.int_val & 0xfff) ==
1328                     (device->device_id & 0xfff))
1329                         return true;
1330         }
1331
1332         return false;
1333 }
1334
1335 /*
1336  *  Arg:
1337  *      video   : video bus device
1338  *
1339  *  Return:
1340  *      < 0     : error
1341  *
1342  *  Call _DOD to enumerate all devices attached to display adapter
1343  *
1344  */
1345
1346 static int acpi_video_device_enumerate(struct acpi_video_bus *video)
1347 {
1348         int status;
1349         int count;
1350         int i;
1351         struct acpi_video_enumerated_device *active_list;
1352         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1353         union acpi_object *dod = NULL;
1354         union acpi_object *obj;
1355
1356         if (!video->cap._DOD)
1357                 return AE_NOT_EXIST;
1358
1359         status = acpi_evaluate_object(video->device->handle, "_DOD", NULL, &buffer);
1360         if (!ACPI_SUCCESS(status)) {
1361                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _DOD"));
1362                 return status;
1363         }
1364
1365         dod = buffer.pointer;
1366         if (!dod || (dod->type != ACPI_TYPE_PACKAGE)) {
1367                 ACPI_EXCEPTION((AE_INFO, status, "Invalid _DOD data"));
1368                 status = -EFAULT;
1369                 goto out;
1370         }
1371
1372         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d video heads in _DOD\n",
1373                           dod->package.count));
1374
1375         active_list = kcalloc(1 + dod->package.count,
1376                               sizeof(struct acpi_video_enumerated_device),
1377                               GFP_KERNEL);
1378         if (!active_list) {
1379                 status = -ENOMEM;
1380                 goto out;
1381         }
1382
1383         count = 0;
1384         for (i = 0; i < dod->package.count; i++) {
1385                 obj = &dod->package.elements[i];
1386
1387                 if (obj->type != ACPI_TYPE_INTEGER) {
1388                         printk(KERN_ERR PREFIX
1389                                 "Invalid _DOD data in element %d\n", i);
1390                         continue;
1391                 }
1392
1393                 active_list[count].value.int_val = obj->integer.value;
1394                 active_list[count].bind_info = NULL;
1395                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "dod element[%d] = %d\n", i,
1396                                   (int)obj->integer.value));
1397                 count++;
1398         }
1399
1400         kfree(video->attached_array);
1401
1402         video->attached_array = active_list;
1403         video->attached_count = count;
1404
1405 out:
1406         kfree(buffer.pointer);
1407         return status;
1408 }
1409
1410 static int
1411 acpi_video_get_next_level(struct acpi_video_device *device,
1412                           u32 level_current, u32 event)
1413 {
1414         int min, max, min_above, max_below, i, l, delta = 255;
1415         max = max_below = 0;
1416         min = min_above = 255;
1417         /* Find closest level to level_current */
1418         for (i = ACPI_VIDEO_FIRST_LEVEL; i < device->brightness->count; i++) {
1419                 l = device->brightness->levels[i];
1420                 if (abs(l - level_current) < abs(delta)) {
1421                         delta = l - level_current;
1422                         if (!delta)
1423                                 break;
1424                 }
1425         }
1426         /* Ajust level_current to closest available level */
1427         level_current += delta;
1428         for (i = ACPI_VIDEO_FIRST_LEVEL; i < device->brightness->count; i++) {
1429                 l = device->brightness->levels[i];
1430                 if (l < min)
1431                         min = l;
1432                 if (l > max)
1433                         max = l;
1434                 if (l < min_above && l > level_current)
1435                         min_above = l;
1436                 if (l > max_below && l < level_current)
1437                         max_below = l;
1438         }
1439
1440         switch (event) {
1441         case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:
1442                 return (level_current < max) ? min_above : min;
1443         case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:
1444                 return (level_current < max) ? min_above : max;
1445         case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:
1446                 return (level_current > min) ? max_below : min;
1447         case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS:
1448         case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:
1449                 return 0;
1450         default:
1451                 return level_current;
1452         }
1453 }
1454
1455 static void
1456 acpi_video_switch_brightness(struct work_struct *work)
1457 {
1458         struct acpi_video_device *device = container_of(to_delayed_work(work),
1459                              struct acpi_video_device, switch_brightness_work);
1460         unsigned long long level_current, level_next;
1461         int event = device->switch_brightness_event;
1462         int result = -EINVAL;
1463
1464         /* no warning message if acpi_backlight=vendor or a quirk is used */
1465         if (!device->backlight)
1466                 return;
1467
1468         if (!device->brightness)
1469                 goto out;
1470
1471         result = acpi_video_device_lcd_get_level_current(device,
1472                                                          &level_current,
1473                                                          false);
1474         if (result)
1475                 goto out;
1476
1477         level_next = acpi_video_get_next_level(device, level_current, event);
1478
1479         result = acpi_video_device_lcd_set_level(device, level_next);
1480
1481         if (!result)
1482                 backlight_force_update(device->backlight,
1483                                        BACKLIGHT_UPDATE_HOTKEY);
1484
1485 out:
1486         if (result)
1487                 printk(KERN_ERR PREFIX "Failed to switch the brightness\n");
1488 }
1489
1490 int acpi_video_get_edid(struct acpi_device *device, int type, int device_id,
1491                         void **edid)
1492 {
1493         struct acpi_video_bus *video;
1494         struct acpi_video_device *video_device;
1495         union acpi_object *buffer = NULL;
1496         acpi_status status;
1497         int i, length;
1498
1499         if (!device || !acpi_driver_data(device))
1500                 return -EINVAL;
1501
1502         video = acpi_driver_data(device);
1503
1504         for (i = 0; i < video->attached_count; i++) {
1505                 video_device = video->attached_array[i].bind_info;
1506                 length = 256;
1507
1508                 if (!video_device)
1509                         continue;
1510
1511                 if (!video_device->cap._DDC)
1512                         continue;
1513
1514                 if (type) {
1515                         switch (type) {
1516                         case ACPI_VIDEO_DISPLAY_CRT:
1517                                 if (!video_device->flags.crt)
1518                                         continue;
1519                                 break;
1520                         case ACPI_VIDEO_DISPLAY_TV:
1521                                 if (!video_device->flags.tvout)
1522                                         continue;
1523                                 break;
1524                         case ACPI_VIDEO_DISPLAY_DVI:
1525                                 if (!video_device->flags.dvi)
1526                                         continue;
1527                                 break;
1528                         case ACPI_VIDEO_DISPLAY_LCD:
1529                                 if (!video_device->flags.lcd)
1530                                         continue;
1531                                 break;
1532                         }
1533                 } else if (video_device->device_id != device_id) {
1534                         continue;
1535                 }
1536
1537                 status = acpi_video_device_EDID(video_device, &buffer, length);
1538
1539                 if (ACPI_FAILURE(status) || !buffer ||
1540                     buffer->type != ACPI_TYPE_BUFFER) {
1541                         length = 128;
1542                         status = acpi_video_device_EDID(video_device, &buffer,
1543                                                         length);
1544                         if (ACPI_FAILURE(status) || !buffer ||
1545                             buffer->type != ACPI_TYPE_BUFFER) {
1546                                 continue;
1547                         }
1548                 }
1549
1550                 *edid = buffer->buffer.pointer;
1551                 return length;
1552         }
1553
1554         return -ENODEV;
1555 }
1556 EXPORT_SYMBOL(acpi_video_get_edid);
1557
1558 static int
1559 acpi_video_bus_get_devices(struct acpi_video_bus *video,
1560                            struct acpi_device *device)
1561 {
1562         int status = 0;
1563         struct acpi_device *dev;
1564
1565         /*
1566          * There are systems where video module known to work fine regardless
1567          * of broken _DOD and ignoring returned value here doesn't cause
1568          * any issues later.
1569          */
1570         acpi_video_device_enumerate(video);
1571
1572         list_for_each_entry(dev, &device->children, node) {
1573
1574                 status = acpi_video_bus_get_one_device(dev, video);
1575                 if (status) {
1576                         dev_err(&dev->dev, "Can't attach device\n");
1577                         break;
1578                 }
1579                 video->child_count++;
1580         }
1581         return status;
1582 }
1583
1584 /* acpi_video interface */
1585
1586 /*
1587  * Win8 requires setting bit2 of _DOS to let firmware know it shouldn't
1588  * preform any automatic brightness change on receiving a notification.
1589  */
1590 static int acpi_video_bus_start_devices(struct acpi_video_bus *video)
1591 {
1592         return acpi_video_bus_DOS(video, 0,
1593                                   acpi_osi_is_win8() ? 1 : 0);
1594 }
1595
1596 static int acpi_video_bus_stop_devices(struct acpi_video_bus *video)
1597 {
1598         return acpi_video_bus_DOS(video, 0,
1599                                   acpi_osi_is_win8() ? 0 : 1);
1600 }
1601
1602 static void acpi_video_bus_notify(struct acpi_device *device, u32 event)
1603 {
1604         struct acpi_video_bus *video = acpi_driver_data(device);
1605         struct input_dev *input;
1606         int keycode = 0;
1607
1608         if (!video || !video->input)
1609                 return;
1610
1611         input = video->input;
1612
1613         switch (event) {
1614         case ACPI_VIDEO_NOTIFY_SWITCH:  /* User requested a switch,
1615                                          * most likely via hotkey. */
1616                 keycode = KEY_SWITCHVIDEOMODE;
1617                 break;
1618
1619         case ACPI_VIDEO_NOTIFY_PROBE:   /* User plugged in or removed a video
1620                                          * connector. */
1621                 acpi_video_device_enumerate(video);
1622                 acpi_video_device_rebind(video);
1623                 keycode = KEY_SWITCHVIDEOMODE;
1624                 break;
1625
1626         case ACPI_VIDEO_NOTIFY_CYCLE:   /* Cycle Display output hotkey pressed. */
1627                 keycode = KEY_SWITCHVIDEOMODE;
1628                 break;
1629         case ACPI_VIDEO_NOTIFY_NEXT_OUTPUT:     /* Next Display output hotkey pressed. */
1630                 keycode = KEY_VIDEO_NEXT;
1631                 break;
1632         case ACPI_VIDEO_NOTIFY_PREV_OUTPUT:     /* previous Display output hotkey pressed. */
1633                 keycode = KEY_VIDEO_PREV;
1634                 break;
1635
1636         default:
1637                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1638                                   "Unsupported event [0x%x]\n", event));
1639                 break;
1640         }
1641
1642         if (acpi_notifier_call_chain(device, event, 0))
1643                 /* Something vetoed the keypress. */
1644                 keycode = 0;
1645
1646         if (keycode && (report_key_events & REPORT_OUTPUT_KEY_EVENTS)) {
1647                 input_report_key(input, keycode, 1);
1648                 input_sync(input);
1649                 input_report_key(input, keycode, 0);
1650                 input_sync(input);
1651         }
1652
1653         return;
1654 }
1655
1656 static void brightness_switch_event(struct acpi_video_device *video_device,
1657                                     u32 event)
1658 {
1659         if (!brightness_switch_enabled)
1660                 return;
1661
1662         video_device->switch_brightness_event = event;
1663         schedule_delayed_work(&video_device->switch_brightness_work, HZ / 10);
1664 }
1665
1666 static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data)
1667 {
1668         struct acpi_video_device *video_device = data;
1669         struct acpi_device *device = NULL;
1670         struct acpi_video_bus *bus;
1671         struct input_dev *input;
1672         int keycode = 0;
1673
1674         if (!video_device)
1675                 return;
1676
1677         device = video_device->dev;
1678         bus = video_device->video;
1679         input = bus->input;
1680
1681         if (hw_changes_brightness > 0) {
1682                 if (video_device->backlight)
1683                         backlight_force_update(video_device->backlight,
1684                                                BACKLIGHT_UPDATE_HOTKEY);
1685                 acpi_notifier_call_chain(device, event, 0);
1686                 return;
1687         }
1688
1689         switch (event) {
1690         case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:        /* Cycle brightness */
1691                 brightness_switch_event(video_device, event);
1692                 keycode = KEY_BRIGHTNESS_CYCLE;
1693                 break;
1694         case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:  /* Increase brightness */
1695                 brightness_switch_event(video_device, event);
1696                 keycode = KEY_BRIGHTNESSUP;
1697                 break;
1698         case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:  /* Decrease brightness */
1699                 brightness_switch_event(video_device, event);
1700                 keycode = KEY_BRIGHTNESSDOWN;
1701                 break;
1702         case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS: /* zero brightness */
1703                 brightness_switch_event(video_device, event);
1704                 keycode = KEY_BRIGHTNESS_ZERO;
1705                 break;
1706         case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:     /* display device off */
1707                 brightness_switch_event(video_device, event);
1708                 keycode = KEY_DISPLAY_OFF;
1709                 break;
1710         default:
1711                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1712                                   "Unsupported event [0x%x]\n", event));
1713                 break;
1714         }
1715
1716         acpi_notifier_call_chain(device, event, 0);
1717
1718         if (keycode && (report_key_events & REPORT_BRIGHTNESS_KEY_EVENTS)) {
1719                 input_report_key(input, keycode, 1);
1720                 input_sync(input);
1721                 input_report_key(input, keycode, 0);
1722                 input_sync(input);
1723         }
1724
1725         return;
1726 }
1727
1728 static int acpi_video_resume(struct notifier_block *nb,
1729                                 unsigned long val, void *ign)
1730 {
1731         struct acpi_video_bus *video;
1732         struct acpi_video_device *video_device;
1733         int i;
1734
1735         switch (val) {
1736         case PM_HIBERNATION_PREPARE:
1737         case PM_SUSPEND_PREPARE:
1738         case PM_RESTORE_PREPARE:
1739                 return NOTIFY_DONE;
1740         }
1741
1742         video = container_of(nb, struct acpi_video_bus, pm_nb);
1743
1744         dev_info(&video->device->dev, "Restoring backlight state\n");
1745
1746         for (i = 0; i < video->attached_count; i++) {
1747                 video_device = video->attached_array[i].bind_info;
1748                 if (video_device && video_device->brightness)
1749                         acpi_video_device_lcd_set_level(video_device,
1750                                         video_device->brightness->curr);
1751         }
1752
1753         return NOTIFY_OK;
1754 }
1755
1756 static acpi_status
1757 acpi_video_bus_match(acpi_handle handle, u32 level, void *context,
1758                         void **return_value)
1759 {
1760         struct acpi_device *device = context;
1761         struct acpi_device *sibling;
1762         int result;
1763
1764         if (handle == device->handle)
1765                 return AE_CTRL_TERMINATE;
1766
1767         result = acpi_bus_get_device(handle, &sibling);
1768         if (result)
1769                 return AE_OK;
1770
1771         if (!strcmp(acpi_device_name(sibling), ACPI_VIDEO_BUS_NAME))
1772                         return AE_ALREADY_EXISTS;
1773
1774         return AE_OK;
1775 }
1776
1777 static void acpi_video_dev_register_backlight(struct acpi_video_device *device)
1778 {
1779         struct backlight_properties props;
1780         struct pci_dev *pdev;
1781         acpi_handle acpi_parent;
1782         struct device *parent = NULL;
1783         int result;
1784         static int count;
1785         char *name;
1786
1787         result = acpi_video_init_brightness(device);
1788         if (result)
1789                 return;
1790
1791         if (disable_backlight_sysfs_if > 0)
1792                 return;
1793
1794         name = kasprintf(GFP_KERNEL, "acpi_video%d", count);
1795         if (!name)
1796                 return;
1797         count++;
1798
1799         acpi_get_parent(device->dev->handle, &acpi_parent);
1800
1801         pdev = acpi_get_pci_dev(acpi_parent);
1802         if (pdev) {
1803                 parent = &pdev->dev;
1804                 pci_dev_put(pdev);
1805         }
1806
1807         memset(&props, 0, sizeof(struct backlight_properties));
1808         props.type = BACKLIGHT_FIRMWARE;
1809         props.max_brightness =
1810                 device->brightness->count - ACPI_VIDEO_FIRST_LEVEL - 1;
1811         device->backlight = backlight_device_register(name,
1812                                                       parent,
1813                                                       device,
1814                                                       &acpi_backlight_ops,
1815                                                       &props);
1816         kfree(name);
1817         if (IS_ERR(device->backlight)) {
1818                 device->backlight = NULL;
1819                 return;
1820         }
1821
1822         /*
1823          * Save current brightness level in case we have to restore it
1824          * before acpi_video_device_lcd_set_level() is called next time.
1825          */
1826         device->backlight->props.brightness =
1827                         acpi_video_get_brightness(device->backlight);
1828
1829         device->cooling_dev = thermal_cooling_device_register("LCD",
1830                                 device->dev, &video_cooling_ops);
1831         if (IS_ERR(device->cooling_dev)) {
1832                 /*
1833                  * Set cooling_dev to NULL so we don't crash trying to free it.
1834                  * Also, why the hell we are returning early and not attempt to
1835                  * register video output if cooling device registration failed?
1836                  * -- dtor
1837                  */
1838                 device->cooling_dev = NULL;
1839                 return;
1840         }
1841
1842         dev_info(&device->dev->dev, "registered as cooling_device%d\n",
1843                  device->cooling_dev->id);
1844         result = sysfs_create_link(&device->dev->dev.kobj,
1845                         &device->cooling_dev->device.kobj,
1846                         "thermal_cooling");
1847         if (result)
1848                 printk(KERN_ERR PREFIX "Create sysfs link\n");
1849         result = sysfs_create_link(&device->cooling_dev->device.kobj,
1850                         &device->dev->dev.kobj, "device");
1851         if (result)
1852                 printk(KERN_ERR PREFIX "Create sysfs link\n");
1853 }
1854
1855 static void acpi_video_run_bcl_for_osi(struct acpi_video_bus *video)
1856 {
1857         struct acpi_video_device *dev;
1858         union acpi_object *levels;
1859
1860         mutex_lock(&video->device_list_lock);
1861         list_for_each_entry(dev, &video->video_device_list, entry) {
1862                 if (!acpi_video_device_lcd_query_levels(dev->dev->handle, &levels))
1863                         kfree(levels);
1864         }
1865         mutex_unlock(&video->device_list_lock);
1866 }
1867
1868 static bool acpi_video_should_register_backlight(struct acpi_video_device *dev)
1869 {
1870         /*
1871          * Do not create backlight device for video output
1872          * device that is not in the enumerated list.
1873          */
1874         if (!acpi_video_device_in_dod(dev)) {
1875                 dev_dbg(&dev->dev->dev, "not in _DOD list, ignore\n");
1876                 return false;
1877         }
1878
1879         if (only_lcd)
1880                 return dev->flags.lcd;
1881         return true;
1882 }
1883
1884 static int acpi_video_bus_register_backlight(struct acpi_video_bus *video)
1885 {
1886         struct acpi_video_device *dev;
1887
1888         if (video->backlight_registered)
1889                 return 0;
1890
1891         acpi_video_run_bcl_for_osi(video);
1892
1893         if (acpi_video_get_backlight_type() != acpi_backlight_video)
1894                 return 0;
1895
1896         mutex_lock(&video->device_list_lock);
1897         list_for_each_entry(dev, &video->video_device_list, entry) {
1898                 if (acpi_video_should_register_backlight(dev))
1899                         acpi_video_dev_register_backlight(dev);
1900         }
1901         mutex_unlock(&video->device_list_lock);
1902
1903         video->backlight_registered = true;
1904
1905         video->pm_nb.notifier_call = acpi_video_resume;
1906         video->pm_nb.priority = 0;
1907         return register_pm_notifier(&video->pm_nb);
1908 }
1909
1910 static void acpi_video_dev_unregister_backlight(struct acpi_video_device *device)
1911 {
1912         if (device->backlight) {
1913                 backlight_device_unregister(device->backlight);
1914                 device->backlight = NULL;
1915         }
1916         if (device->brightness) {
1917                 kfree(device->brightness->levels);
1918                 kfree(device->brightness);
1919                 device->brightness = NULL;
1920         }
1921         if (device->cooling_dev) {
1922                 sysfs_remove_link(&device->dev->dev.kobj, "thermal_cooling");
1923                 sysfs_remove_link(&device->cooling_dev->device.kobj, "device");
1924                 thermal_cooling_device_unregister(device->cooling_dev);
1925                 device->cooling_dev = NULL;
1926         }
1927 }
1928
1929 static int acpi_video_bus_unregister_backlight(struct acpi_video_bus *video)
1930 {
1931         struct acpi_video_device *dev;
1932         int error;
1933
1934         if (!video->backlight_registered)
1935                 return 0;
1936
1937         error = unregister_pm_notifier(&video->pm_nb);
1938
1939         mutex_lock(&video->device_list_lock);
1940         list_for_each_entry(dev, &video->video_device_list, entry)
1941                 acpi_video_dev_unregister_backlight(dev);
1942         mutex_unlock(&video->device_list_lock);
1943
1944         video->backlight_registered = false;
1945
1946         return error;
1947 }
1948
1949 static void acpi_video_dev_add_notify_handler(struct acpi_video_device *device)
1950 {
1951         acpi_status status;
1952         struct acpi_device *adev = device->dev;
1953
1954         status = acpi_install_notify_handler(adev->handle, ACPI_DEVICE_NOTIFY,
1955                                              acpi_video_device_notify, device);
1956         if (ACPI_FAILURE(status))
1957                 dev_err(&adev->dev, "Error installing notify handler\n");
1958         else
1959                 device->flags.notify = 1;
1960 }
1961
1962 static int acpi_video_bus_add_notify_handler(struct acpi_video_bus *video)
1963 {
1964         struct input_dev *input;
1965         struct acpi_video_device *dev;
1966         int error;
1967
1968         video->input = input = input_allocate_device();
1969         if (!input) {
1970                 error = -ENOMEM;
1971                 goto out;
1972         }
1973
1974         error = acpi_video_bus_start_devices(video);
1975         if (error)
1976                 goto err_free_input;
1977
1978         snprintf(video->phys, sizeof(video->phys),
1979                         "%s/video/input0", acpi_device_hid(video->device));
1980
1981         input->name = acpi_device_name(video->device);
1982         input->phys = video->phys;
1983         input->id.bustype = BUS_HOST;
1984         input->id.product = 0x06;
1985         input->dev.parent = &video->device->dev;
1986         input->evbit[0] = BIT(EV_KEY);
1987         set_bit(KEY_SWITCHVIDEOMODE, input->keybit);
1988         set_bit(KEY_VIDEO_NEXT, input->keybit);
1989         set_bit(KEY_VIDEO_PREV, input->keybit);
1990         set_bit(KEY_BRIGHTNESS_CYCLE, input->keybit);
1991         set_bit(KEY_BRIGHTNESSUP, input->keybit);
1992         set_bit(KEY_BRIGHTNESSDOWN, input->keybit);
1993         set_bit(KEY_BRIGHTNESS_ZERO, input->keybit);
1994         set_bit(KEY_DISPLAY_OFF, input->keybit);
1995
1996         error = input_register_device(input);
1997         if (error)
1998                 goto err_stop_dev;
1999
2000         mutex_lock(&video->device_list_lock);
2001         list_for_each_entry(dev, &video->video_device_list, entry)
2002                 acpi_video_dev_add_notify_handler(dev);
2003         mutex_unlock(&video->device_list_lock);
2004
2005         return 0;
2006
2007 err_stop_dev:
2008         acpi_video_bus_stop_devices(video);
2009 err_free_input:
2010         input_free_device(input);
2011         video->input = NULL;
2012 out:
2013         return error;
2014 }
2015
2016 static void acpi_video_dev_remove_notify_handler(struct acpi_video_device *dev)
2017 {
2018         if (dev->flags.notify) {
2019                 acpi_remove_notify_handler(dev->dev->handle, ACPI_DEVICE_NOTIFY,
2020                                            acpi_video_device_notify);
2021                 dev->flags.notify = 0;
2022         }
2023 }
2024
2025 static void acpi_video_bus_remove_notify_handler(struct acpi_video_bus *video)
2026 {
2027         struct acpi_video_device *dev;
2028
2029         mutex_lock(&video->device_list_lock);
2030         list_for_each_entry(dev, &video->video_device_list, entry)
2031                 acpi_video_dev_remove_notify_handler(dev);
2032         mutex_unlock(&video->device_list_lock);
2033
2034         acpi_video_bus_stop_devices(video);
2035         input_unregister_device(video->input);
2036         video->input = NULL;
2037 }
2038
2039 static int acpi_video_bus_put_devices(struct acpi_video_bus *video)
2040 {
2041         struct acpi_video_device *dev, *next;
2042
2043         mutex_lock(&video->device_list_lock);
2044         list_for_each_entry_safe(dev, next, &video->video_device_list, entry) {
2045                 list_del(&dev->entry);
2046                 kfree(dev);
2047         }
2048         mutex_unlock(&video->device_list_lock);
2049
2050         return 0;
2051 }
2052
2053 static int instance;
2054
2055 static int acpi_video_bus_add(struct acpi_device *device)
2056 {
2057         struct acpi_video_bus *video;
2058         int error;
2059         acpi_status status;
2060
2061         status = acpi_walk_namespace(ACPI_TYPE_DEVICE,
2062                                 device->parent->handle, 1,
2063                                 acpi_video_bus_match, NULL,
2064                                 device, NULL);
2065         if (status == AE_ALREADY_EXISTS) {
2066                 printk(KERN_WARNING FW_BUG
2067                         "Duplicate ACPI video bus devices for the"
2068                         " same VGA controller, please try module "
2069                         "parameter \"video.allow_duplicates=1\""
2070                         "if the current driver doesn't work.\n");
2071                 if (!allow_duplicates)
2072                         return -ENODEV;
2073         }
2074
2075         video = kzalloc(sizeof(struct acpi_video_bus), GFP_KERNEL);
2076         if (!video)
2077                 return -ENOMEM;
2078
2079         /* a hack to fix the duplicate name "VID" problem on T61 */
2080         if (!strcmp(device->pnp.bus_id, "VID")) {
2081                 if (instance)
2082                         device->pnp.bus_id[3] = '0' + instance;
2083                 instance++;
2084         }
2085         /* a hack to fix the duplicate name "VGA" problem on Pa 3553 */
2086         if (!strcmp(device->pnp.bus_id, "VGA")) {
2087                 if (instance)
2088                         device->pnp.bus_id[3] = '0' + instance;
2089                 instance++;
2090         }
2091
2092         video->device = device;
2093         strcpy(acpi_device_name(device), ACPI_VIDEO_BUS_NAME);
2094         strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
2095         device->driver_data = video;
2096
2097         acpi_video_bus_find_cap(video);
2098         error = acpi_video_bus_check(video);
2099         if (error)
2100                 goto err_free_video;
2101
2102         mutex_init(&video->device_list_lock);
2103         INIT_LIST_HEAD(&video->video_device_list);
2104
2105         error = acpi_video_bus_get_devices(video, device);
2106         if (error)
2107                 goto err_put_video;
2108
2109         printk(KERN_INFO PREFIX "%s [%s] (multi-head: %s  rom: %s  post: %s)\n",
2110                ACPI_VIDEO_DEVICE_NAME, acpi_device_bid(device),
2111                video->flags.multihead ? "yes" : "no",
2112                video->flags.rom ? "yes" : "no",
2113                video->flags.post ? "yes" : "no");
2114         mutex_lock(&video_list_lock);
2115         list_add_tail(&video->entry, &video_bus_head);
2116         mutex_unlock(&video_list_lock);
2117
2118         acpi_video_bus_register_backlight(video);
2119         acpi_video_bus_add_notify_handler(video);
2120
2121         return 0;
2122
2123 err_put_video:
2124         acpi_video_bus_put_devices(video);
2125         kfree(video->attached_array);
2126 err_free_video:
2127         kfree(video);
2128         device->driver_data = NULL;
2129
2130         return error;
2131 }
2132
2133 static int acpi_video_bus_remove(struct acpi_device *device)
2134 {
2135         struct acpi_video_bus *video = NULL;
2136
2137
2138         if (!device || !acpi_driver_data(device))
2139                 return -EINVAL;
2140
2141         video = acpi_driver_data(device);
2142
2143         acpi_video_bus_remove_notify_handler(video);
2144         acpi_video_bus_unregister_backlight(video);
2145         acpi_video_bus_put_devices(video);
2146
2147         mutex_lock(&video_list_lock);
2148         list_del(&video->entry);
2149         mutex_unlock(&video_list_lock);
2150
2151         kfree(video->attached_array);
2152         kfree(video);
2153
2154         return 0;
2155 }
2156
2157 static int __init is_i740(struct pci_dev *dev)
2158 {
2159         if (dev->device == 0x00D1)
2160                 return 1;
2161         if (dev->device == 0x7000)
2162                 return 1;
2163         return 0;
2164 }
2165
2166 static int __init intel_opregion_present(void)
2167 {
2168         int opregion = 0;
2169         struct pci_dev *dev = NULL;
2170         u32 address;
2171
2172         for_each_pci_dev(dev) {
2173                 if ((dev->class >> 8) != PCI_CLASS_DISPLAY_VGA)
2174                         continue;
2175                 if (dev->vendor != PCI_VENDOR_ID_INTEL)
2176                         continue;
2177                 /* We don't want to poke around undefined i740 registers */
2178                 if (is_i740(dev))
2179                         continue;
2180                 pci_read_config_dword(dev, 0xfc, &address);
2181                 if (!address)
2182                         continue;
2183                 opregion = 1;
2184         }
2185         return opregion;
2186 }
2187
2188 /* Check if the chassis-type indicates there is no builtin LCD panel */
2189 static bool dmi_is_desktop(void)
2190 {
2191         const char *chassis_type;
2192         unsigned long type;
2193
2194         chassis_type = dmi_get_system_info(DMI_CHASSIS_TYPE);
2195         if (!chassis_type)
2196                 return false;
2197
2198         if (kstrtoul(chassis_type, 10, &type) != 0)
2199                 return false;
2200
2201         switch (type) {
2202         case 0x03: /* Desktop */
2203         case 0x04: /* Low Profile Desktop */
2204         case 0x05: /* Pizza Box */
2205         case 0x06: /* Mini Tower */
2206         case 0x07: /* Tower */
2207         case 0x10: /* Lunch Box */
2208         case 0x11: /* Main Server Chassis */
2209                 return true;
2210         }
2211
2212         return false;
2213 }
2214
2215 int acpi_video_register(void)
2216 {
2217         int ret = 0;
2218
2219         mutex_lock(&register_count_mutex);
2220         if (register_count) {
2221                 /*
2222                  * if the function of acpi_video_register is already called,
2223                  * don't register the acpi_vide_bus again and return no error.
2224                  */
2225                 goto leave;
2226         }
2227
2228         /*
2229          * We're seeing a lot of bogus backlight interfaces on newer machines
2230          * without a LCD such as desktops, servers and HDMI sticks. Checking
2231          * the lcd flag fixes this, so enable this on any machines which are
2232          * win8 ready (where we also prefer the native backlight driver, so
2233          * normally the acpi_video code should not register there anyways).
2234          */
2235         if (only_lcd == -1) {
2236                 if (dmi_is_desktop() && acpi_osi_is_win8())
2237                         only_lcd = true;
2238                 else
2239                         only_lcd = false;
2240         }
2241
2242         dmi_check_system(video_dmi_table);
2243
2244         ret = acpi_bus_register_driver(&acpi_video_bus);
2245         if (ret)
2246                 goto leave;
2247
2248         /*
2249          * When the acpi_video_bus is loaded successfully, increase
2250          * the counter reference.
2251          */
2252         register_count = 1;
2253
2254 leave:
2255         mutex_unlock(&register_count_mutex);
2256         return ret;
2257 }
2258 EXPORT_SYMBOL(acpi_video_register);
2259
2260 void acpi_video_unregister(void)
2261 {
2262         mutex_lock(&register_count_mutex);
2263         if (register_count) {
2264                 acpi_bus_unregister_driver(&acpi_video_bus);
2265                 register_count = 0;
2266         }
2267         mutex_unlock(&register_count_mutex);
2268 }
2269 EXPORT_SYMBOL(acpi_video_unregister);
2270
2271 void acpi_video_unregister_backlight(void)
2272 {
2273         struct acpi_video_bus *video;
2274
2275         mutex_lock(&register_count_mutex);
2276         if (register_count) {
2277                 mutex_lock(&video_list_lock);
2278                 list_for_each_entry(video, &video_bus_head, entry)
2279                         acpi_video_bus_unregister_backlight(video);
2280                 mutex_unlock(&video_list_lock);
2281         }
2282         mutex_unlock(&register_count_mutex);
2283 }
2284
2285 bool acpi_video_handles_brightness_key_presses(void)
2286 {
2287         bool have_video_busses;
2288
2289         mutex_lock(&video_list_lock);
2290         have_video_busses = !list_empty(&video_bus_head);
2291         mutex_unlock(&video_list_lock);
2292
2293         return have_video_busses &&
2294                (report_key_events & REPORT_BRIGHTNESS_KEY_EVENTS);
2295 }
2296 EXPORT_SYMBOL(acpi_video_handles_brightness_key_presses);
2297
2298 /*
2299  * This is kind of nasty. Hardware using Intel chipsets may require
2300  * the video opregion code to be run first in order to initialise
2301  * state before any ACPI video calls are made. To handle this we defer
2302  * registration of the video class until the opregion code has run.
2303  */
2304
2305 static int __init acpi_video_init(void)
2306 {
2307         /*
2308          * Let the module load even if ACPI is disabled (e.g. due to
2309          * a broken BIOS) so that i915.ko can still be loaded on such
2310          * old systems without an AcpiOpRegion.
2311          *
2312          * acpi_video_register() will report -ENODEV later as well due
2313          * to acpi_disabled when i915.ko tries to register itself afterwards.
2314          */
2315         if (acpi_disabled)
2316                 return 0;
2317
2318         if (intel_opregion_present())
2319                 return 0;
2320
2321         return acpi_video_register();
2322 }
2323
2324 static void __exit acpi_video_exit(void)
2325 {
2326         acpi_video_detect_exit();
2327         acpi_video_unregister();
2328
2329         return;
2330 }
2331
2332 module_init(acpi_video_init);
2333 module_exit(acpi_video_exit);