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          * Some machine's _DOD IDs don't have bit 31(Device ID Scheme) set
 516          * but the IDs actually follow the Device ID Scheme.
 517          */
 518         {
 519          /* https://bugzilla.kernel.org/show_bug.cgi?id=104121 */
 520          .callback = video_set_device_id_scheme,
 521          .ident = "ESPRIMO Mobile M9410",
 522          .matches = {
 523                 DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU SIEMENS"),
 524                 DMI_MATCH(DMI_PRODUCT_NAME, "ESPRIMO Mobile M9410"),
 525                 },
 526         },
 527         /*
 528          * Some machines have multiple video output devices, but only the one
 529          * that is the type of LCD can do the backlight control so we should not
 530          * register backlight interface for other video output devices.
 531          */
 532         {
 533          /* https://bugzilla.kernel.org/show_bug.cgi?id=104121 */
 534          .callback = video_enable_only_lcd,
 535          .ident = "ESPRIMO Mobile M9410",
 536          .matches = {
 537                 DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU SIEMENS"),
 538                 DMI_MATCH(DMI_PRODUCT_NAME, "ESPRIMO Mobile M9410"),
 539                 },
 540         },
 541         /*
 542          * Some machines report wrong key events on the acpi-bus, suppress
 543          * key event reporting on these.  Note this is only intended to work
 544          * around events which are plain wrong. In some cases we get double
 545          * events, in this case acpi-video is considered the canonical source
 546          * and the events from the other source should be filtered. E.g.
 547          * by calling acpi_video_handles_brightness_key_presses() from the
 548          * vendor acpi/wmi driver or by using /lib/udev/hwdb.d/60-keyboard.hwdb
 549          */
 550         {
 551          .callback = video_set_report_key_events,
 552          .driver_data = (void *)((uintptr_t)REPORT_OUTPUT_KEY_EVENTS),
 553          .ident = "Dell Vostro V131",
 554          .matches = {
 555                 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 556                 DMI_MATCH(DMI_PRODUCT_NAME, "Vostro V131"),
 557                 },
 558         },
 559         {
 560          .callback = video_set_report_key_events,
 561          .driver_data = (void *)((uintptr_t)REPORT_BRIGHTNESS_KEY_EVENTS),
 562          .ident = "Dell Vostro 3350",
 563          .matches = {
 564                 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 565                 DMI_MATCH(DMI_PRODUCT_NAME, "Vostro 3350"),
 566                 },
 567         },
 568         /*
 569          * Some machines change the brightness themselves when a brightness
 570          * hotkey gets pressed, despite us telling them not to. In this case
 571          * acpi_video_device_notify() should only call backlight_force_update(
 572          * BACKLIGHT_UPDATE_HOTKEY) and not do anything else.
 573          */
 574         {
 575          /* https://bugzilla.kernel.org/show_bug.cgi?id=204077 */
 576          .callback = video_hw_changes_brightness,
 577          .ident = "Packard Bell EasyNote MZ35",
 578          .matches = {
 579                 DMI_MATCH(DMI_SYS_VENDOR, "Packard Bell"),
 580                 DMI_MATCH(DMI_PRODUCT_NAME, "EasyNote MZ35"),
 581                 },
 582         },
 583         {}
 584 };
 585
 586 static unsigned long long
 587 acpi_video_bqc_value_to_level(struct acpi_video_device *device,
 588                               unsigned long long bqc_value)
 589 {
 590         unsigned long long level;
 591
 592         if (device->brightness->flags._BQC_use_index) {
 593                 /*
 594                  * _BQC returns an index that doesn't account for the first 2
 595                  * items with special meaning (see enum acpi_video_level_idx),
 596                  * so we need to compensate for that by offsetting ourselves
 597                  */
 598                 if (device->brightness->flags._BCL_reversed)
 599                         bqc_value = device->brightness->count -
 600                                 ACPI_VIDEO_FIRST_LEVEL - 1 - bqc_value;
 601
 602                 level = device->brightness->levels[bqc_value +
 603                                                    ACPI_VIDEO_FIRST_LEVEL];
 604         } else {
 605                 level = bqc_value;
 606         }
 607
 608         level += bqc_offset_aml_bug_workaround;
 609
 610         return level;
 611 }
 612
 613 static int
 614 acpi_video_device_lcd_get_level_current(struct acpi_video_device *device,
 615                                         unsigned long long *level, bool raw)
 616 {
 617         acpi_status status = AE_OK;
 618         int i;
 619
 620         if (device->cap._BQC || device->cap._BCQ) {
 621                 char *buf = device->cap._BQC ? "_BQC" : "_BCQ";
 622
 623                 status = acpi_evaluate_integer(device->dev->handle, buf,
 624                                                 NULL, level);
 625                 if (ACPI_SUCCESS(status)) {
 626                         if (raw) {
 627                                 /*
 628                                  * Caller has indicated he wants the raw
 629                                  * value returned by _BQC, so don't furtherly
 630                                  * mess with the value.
 631                                  */
 632                                 return 0;
 633                         }
 634
 635                         *level = acpi_video_bqc_value_to_level(device, *level);
 636
 637                         for (i = ACPI_VIDEO_FIRST_LEVEL;
 638                              i < device->brightness->count; i++)
 639                                 if (device->brightness->levels[i] == *level) {
 640                                         device->brightness->curr = *level;
 641                                         return 0;
 642                                 }
 643                         /*
 644                          * BQC returned an invalid level.
 645                          * Stop using it.
 646                          */
 647                         ACPI_WARNING((AE_INFO,
 648                                       "%s returned an invalid level",
 649                                       buf));
 650                         device->cap._BQC = device->cap._BCQ = 0;
 651                 } else {
 652                         /*
 653                          * Fixme:
 654                          * should we return an error or ignore this failure?
 655                          * dev->brightness->curr is a cached value which stores
 656                          * the correct current backlight level in most cases.
 657                          * ACPI video backlight still works w/ buggy _BQC.
 658                          * http://bugzilla.kernel.org/show_bug.cgi?id=12233
 659                          */
 660                         ACPI_WARNING((AE_INFO, "Evaluating %s failed", buf));
 661                         device->cap._BQC = device->cap._BCQ = 0;
 662                 }
 663         }
 664
 665         *level = device->brightness->curr;
 666         return 0;
 667 }
 668
 669 static int
 670 acpi_video_device_EDID(struct acpi_video_device *device,
 671                        union acpi_object **edid, ssize_t length)
 672 {
 673         int status;
 674         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 675         union acpi_object *obj;
 676         union acpi_object arg0 = { ACPI_TYPE_INTEGER };
 677         struct acpi_object_list args = { 1, &arg0 };
 678
 679
 680         *edid = NULL;
 681
 682         if (!device)
 683                 return -ENODEV;
 684         if (length == 128)
 685                 arg0.integer.value = 1;
 686         else if (length == 256)
 687                 arg0.integer.value = 2;
 688         else
 689                 return -EINVAL;
 690
 691         status = acpi_evaluate_object(device->dev->handle, "_DDC", &args, &buffer);
 692         if (ACPI_FAILURE(status))
 693                 return -ENODEV;
 694
 695         obj = buffer.pointer;
 696
 697         if (obj && obj->type == ACPI_TYPE_BUFFER)
 698                 *edid = obj;
 699         else {
 700                 printk(KERN_ERR PREFIX "Invalid _DDC data\n");
 701                 status = -EFAULT;
 702                 kfree(obj);
 703         }
 704
 705         return status;
 706 }
 707
 708 /* bus */
 709
 710 /*
 711  *  Arg:
 712  *      video           : video bus device pointer
 713  *      bios_flag       :
 714  *              0.      The system BIOS should NOT automatically switch(toggle)
 715  *                      the active display output.
 716  *              1.      The system BIOS should automatically switch (toggle) the
 717  *                      active display output. No switch event.
 718  *              2.      The _DGS value should be locked.
 719  *              3.      The system BIOS should not automatically switch (toggle) the
 720  *                      active display output, but instead generate the display switch
 721  *                      event notify code.
 722  *      lcd_flag        :
 723  *              0.      The system BIOS should automatically control the brightness level
 724  *                      of the LCD when the power changes from AC to DC
 725  *              1.      The system BIOS should NOT automatically control the brightness
 726  *                      level of the LCD when the power changes from AC to DC.
 727  *  Return Value:
 728  *              -EINVAL wrong arg.
 729  */
 730
 731 static int
 732 acpi_video_bus_DOS(struct acpi_video_bus *video, int bios_flag, int lcd_flag)
 733 {
 734         acpi_status status;
 735
 736         if (!video->cap._DOS)
 737                 return 0;
 738
 739         if (bios_flag < 0 || bios_flag > 3 || lcd_flag < 0 || lcd_flag > 1)
 740                 return -EINVAL;
 741         video->dos_setting = (lcd_flag << 2) | bios_flag;
 742         status = acpi_execute_simple_method(video->device->handle, "_DOS",
 743                                             (lcd_flag << 2) | bios_flag);
 744         if (ACPI_FAILURE(status))
 745                 return -EIO;
 746
 747         return 0;
 748 }
 749
 750 /*
 751  * Simple comparison function used to sort backlight levels.
 752  */
 753
 754 static int
 755 acpi_video_cmp_level(const void *a, const void *b)
 756 {
 757         return *(int *)a - *(int *)b;
 758 }
 759
 760 /*
 761  * Decides if _BQC/_BCQ for this system is usable
 762  *
 763  * We do this by changing the level first and then read out the current
 764  * brightness level, if the value does not match, find out if it is using
 765  * index. If not, clear the _BQC/_BCQ capability.
 766  */
 767 static int acpi_video_bqc_quirk(struct acpi_video_device *device,
 768                                 int max_level, int current_level)
 769 {
 770         struct acpi_video_device_brightness *br = device->brightness;
 771         int result;
 772         unsigned long long level;
 773         int test_level;
 774
 775         /* don't mess with existing known broken systems */
 776         if (bqc_offset_aml_bug_workaround)
 777                 return 0;
 778
 779         /*
 780          * Some systems always report current brightness level as maximum
 781          * through _BQC, we need to test another value for them. However,
 782          * there is a subtlety:
 783          *
 784          * If the _BCL package ordering is descending, the first level
 785          * (br->levels[2]) is likely to be 0, and if the number of levels
 786          * matches the number of steps, we might confuse a returned level to
 787          * mean the index.
 788          *
 789          * For example:
 790          *
 791          *     current_level = max_level = 100
 792          *     test_level = 0
 793          *     returned level = 100
 794          *
 795          * In this case 100 means the level, not the index, and _BCM failed.
 796          * Still, if the _BCL package ordering is descending, the index of
 797          * level 0 is also 100, so we assume _BQC is indexed, when it's not.
 798          *
 799          * This causes all _BQC calls to return bogus values causing weird
 800          * behavior from the user's perspective.  For example:
 801          *
 802          * xbacklight -set 10; xbacklight -set 20;
 803          *
 804          * would flash to 90% and then slowly down to the desired level (20).
 805          *
 806          * The solution is simple; test anything other than the first level
 807          * (e.g. 1).
 808          */
 809         test_level = current_level == max_level
 810                 ? br->levels[ACPI_VIDEO_FIRST_LEVEL + 1]
 811                 : max_level;
 812
 813         result = acpi_video_device_lcd_set_level(device, test_level);
 814         if (result)
 815                 return result;
 816
 817         result = acpi_video_device_lcd_get_level_current(device, &level, true);
 818         if (result)
 819                 return result;
 820
 821         if (level != test_level) {
 822                 /* buggy _BQC found, need to find out if it uses index */
 823                 if (level < br->count) {
 824                         if (br->flags._BCL_reversed)
 825                                 level = br->count - ACPI_VIDEO_FIRST_LEVEL - 1 - level;
 826                         if (br->levels[level + ACPI_VIDEO_FIRST_LEVEL] == test_level)
 827                                 br->flags._BQC_use_index = 1;
 828                 }
 829
 830                 if (!br->flags._BQC_use_index)
 831                         device->cap._BQC = device->cap._BCQ = 0;
 832         }
 833
 834         return 0;
 835 }
 836
 837 int acpi_video_get_levels(struct acpi_device *device,
 838                           struct acpi_video_device_brightness **dev_br,
 839                           int *pmax_level)
 840 {
 841         union acpi_object *obj = NULL;
 842         int i, max_level = 0, count = 0, level_ac_battery = 0;
 843         union acpi_object *o;
 844         struct acpi_video_device_brightness *br = NULL;
 845         int result = 0;
 846         u32 value;
 847
 848         if (!ACPI_SUCCESS(acpi_video_device_lcd_query_levels(device->handle,
 849                                                                 &obj))) {
 850                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Could not query available "
 851                                                 "LCD brightness level\n"));
 852                 result = -ENODEV;
 853                 goto out;
 854         }
 855
 856         if (obj->package.count < ACPI_VIDEO_FIRST_LEVEL) {
 857                 result = -EINVAL;
 858                 goto out;
 859         }
 860
 861         br = kzalloc(sizeof(*br), GFP_KERNEL);
 862         if (!br) {
 863                 printk(KERN_ERR "can't allocate memory\n");
 864                 result = -ENOMEM;
 865                 goto out;
 866         }
 867
 868         /*
 869          * Note that we have to reserve 2 extra items (ACPI_VIDEO_FIRST_LEVEL),
 870          * in order to account for buggy BIOS which don't export the first two
 871          * special levels (see below)
 872          */
 873         br->levels = kmalloc((obj->package.count + ACPI_VIDEO_FIRST_LEVEL) *
 874                              sizeof(*br->levels), GFP_KERNEL);
 875         if (!br->levels) {
 876                 result = -ENOMEM;
 877                 goto out_free;
 878         }
 879
 880         for (i = 0; i < obj->package.count; i++) {
 881                 o = (union acpi_object *)&obj->package.elements[i];
 882                 if (o->type != ACPI_TYPE_INTEGER) {
 883                         printk(KERN_ERR PREFIX "Invalid data\n");
 884                         continue;
 885                 }
 886                 value = (u32) o->integer.value;
 887                 /* Skip duplicate entries */
 888                 if (count > ACPI_VIDEO_FIRST_LEVEL
 889                     && br->levels[count - 1] == value)
 890                         continue;
 891
 892                 br->levels[count] = value;
 893
 894                 if (br->levels[count] > max_level)
 895                         max_level = br->levels[count];
 896                 count++;
 897         }
 898
 899         /*
 900          * some buggy BIOS don't export the levels
 901          * when machine is on AC/Battery in _BCL package.
 902          * In this case, the first two elements in _BCL packages
 903          * are also supported brightness levels that OS should take care of.
 904          */
 905         for (i = ACPI_VIDEO_FIRST_LEVEL; i < count; i++) {
 906                 if (br->levels[i] == br->levels[ACPI_VIDEO_AC_LEVEL])
 907                         level_ac_battery++;
 908                 if (br->levels[i] == br->levels[ACPI_VIDEO_BATTERY_LEVEL])
 909                         level_ac_battery++;
 910         }
 911
 912         if (level_ac_battery < ACPI_VIDEO_FIRST_LEVEL) {
 913                 level_ac_battery = ACPI_VIDEO_FIRST_LEVEL - level_ac_battery;
 914                 br->flags._BCL_no_ac_battery_levels = 1;
 915                 for (i = (count - 1 + level_ac_battery);
 916                      i >= ACPI_VIDEO_FIRST_LEVEL; i--)
 917                         br->levels[i] = br->levels[i - level_ac_battery];
 918                 count += level_ac_battery;
 919         } else if (level_ac_battery > ACPI_VIDEO_FIRST_LEVEL)
 920                 ACPI_ERROR((AE_INFO, "Too many duplicates in _BCL package"));
 921
 922         /* Check if the _BCL package is in a reversed order */
 923         if (max_level == br->levels[ACPI_VIDEO_FIRST_LEVEL]) {
 924                 br->flags._BCL_reversed = 1;
 925                 sort(&br->levels[ACPI_VIDEO_FIRST_LEVEL],
 926                      count - ACPI_VIDEO_FIRST_LEVEL,
 927                      sizeof(br->levels[ACPI_VIDEO_FIRST_LEVEL]),
 928                      acpi_video_cmp_level, NULL);
 929         } else if (max_level != br->levels[count - 1])
 930                 ACPI_ERROR((AE_INFO,
 931                             "Found unordered _BCL package"));
 932
 933         br->count = count;
 934         *dev_br = br;
 935         if (pmax_level)
 936                 *pmax_level = max_level;
 937
 938 out:
 939         kfree(obj);
 940         return result;
 941 out_free:
 942         kfree(br);
 943         goto out;
 944 }
 945 EXPORT_SYMBOL(acpi_video_get_levels);
 946
 947 /*
 948  *  Arg:
 949  *      device  : video output device (LCD, CRT, ..)
 950  *
 951  *  Return Value:
 952  *      Maximum brightness level
 953  *
 954  *  Allocate and initialize device->brightness.
 955  */
 956
 957 static int
 958 acpi_video_init_brightness(struct acpi_video_device *device)
 959 {
 960         int i, max_level = 0;
 961         unsigned long long level, level_old;
 962         struct acpi_video_device_brightness *br = NULL;
 963         int result = -EINVAL;
 964
 965         result = acpi_video_get_levels(device->dev, &br, &max_level);
 966         if (result)
 967                 return result;
 968         device->brightness = br;
 969
 970         /* _BQC uses INDEX while _BCL uses VALUE in some laptops */
 971         br->curr = level = max_level;
 972
 973         if (!device->cap._BQC)
 974                 goto set_level;
 975
 976         result = acpi_video_device_lcd_get_level_current(device,
 977                                                          &level_old, true);
 978         if (result)
 979                 goto out_free_levels;
 980
 981         result = acpi_video_bqc_quirk(device, max_level, level_old);
 982         if (result)
 983                 goto out_free_levels;
 984         /*
 985          * cap._BQC may get cleared due to _BQC is found to be broken
 986          * in acpi_video_bqc_quirk, so check again here.
 987          */
 988         if (!device->cap._BQC)
 989                 goto set_level;
 990
 991         level = acpi_video_bqc_value_to_level(device, level_old);
 992         /*
 993          * On some buggy laptops, _BQC returns an uninitialized
 994          * value when invoked for the first time, i.e.
 995          * level_old is invalid (no matter whether it's a level
 996          * or an index). Set the backlight to max_level in this case.
 997          */
 998         for (i = ACPI_VIDEO_FIRST_LEVEL; i < br->count; i++)
 999                 if (level == br->levels[i])
1000                         break;
1001         if (i == br->count || !level)
1002                 level = max_level;
1003
1004 set_level:
1005         result = acpi_video_device_lcd_set_level(device, level);
1006         if (result)
1007                 goto out_free_levels;
1008
1009         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1010                           "found %d brightness levels\n",
1011                           br->count - ACPI_VIDEO_FIRST_LEVEL));
1012         return 0;
1013
1014 out_free_levels:
1015         kfree(br->levels);
1016         kfree(br);
1017         device->brightness = NULL;
1018         return result;
1019 }
1020
1021 /*
1022  *  Arg:
1023  *      device  : video output device (LCD, CRT, ..)
1024  *
1025  *  Return Value:
1026  *      None
1027  *
1028  *  Find out all required AML methods defined under the output
1029  *  device.
1030  */
1031
1032 static void acpi_video_device_find_cap(struct acpi_video_device *device)
1033 {
1034         if (acpi_has_method(device->dev->handle, "_ADR"))
1035                 device->cap._ADR = 1;
1036         if (acpi_has_method(device->dev->handle, "_BCL"))
1037                 device->cap._BCL = 1;
1038         if (acpi_has_method(device->dev->handle, "_BCM"))
1039                 device->cap._BCM = 1;
1040         if (acpi_has_method(device->dev->handle, "_BQC")) {
1041                 device->cap._BQC = 1;
1042         } else if (acpi_has_method(device->dev->handle, "_BCQ")) {
1043                 printk(KERN_WARNING FW_BUG "_BCQ is used instead of _BQC\n");
1044                 device->cap._BCQ = 1;
1045         }
1046
1047         if (acpi_has_method(device->dev->handle, "_DDC"))
1048                 device->cap._DDC = 1;
1049 }
1050
1051 /*
1052  *  Arg:
1053  *      device  : video output device (VGA)
1054  *
1055  *  Return Value:
1056  *      None
1057  *
1058  *  Find out all required AML methods defined under the video bus device.
1059  */
1060
1061 static void acpi_video_bus_find_cap(struct acpi_video_bus *video)
1062 {
1063         if (acpi_has_method(video->device->handle, "_DOS"))
1064                 video->cap._DOS = 1;
1065         if (acpi_has_method(video->device->handle, "_DOD"))
1066                 video->cap._DOD = 1;
1067         if (acpi_has_method(video->device->handle, "_ROM"))
1068                 video->cap._ROM = 1;
1069         if (acpi_has_method(video->device->handle, "_GPD"))
1070                 video->cap._GPD = 1;
1071         if (acpi_has_method(video->device->handle, "_SPD"))
1072                 video->cap._SPD = 1;
1073         if (acpi_has_method(video->device->handle, "_VPO"))
1074                 video->cap._VPO = 1;
1075 }
1076
1077 /*
1078  * Check whether the video bus device has required AML method to
1079  * support the desired features
1080  */
1081
1082 static int acpi_video_bus_check(struct acpi_video_bus *video)
1083 {
1084         acpi_status status = -ENOENT;
1085         struct pci_dev *dev;
1086
1087         if (!video)
1088                 return -EINVAL;
1089
1090         dev = acpi_get_pci_dev(video->device->handle);
1091         if (!dev)
1092                 return -ENODEV;
1093         pci_dev_put(dev);
1094
1095         /*
1096          * Since there is no HID, CID and so on for VGA driver, we have
1097          * to check well known required nodes.
1098          */
1099
1100         /* Does this device support video switching? */
1101         if (video->cap._DOS || video->cap._DOD) {
1102                 if (!video->cap._DOS) {
1103                         printk(KERN_WARNING FW_BUG
1104                                 "ACPI(%s) defines _DOD but not _DOS\n",
1105                                 acpi_device_bid(video->device));
1106                 }
1107                 video->flags.multihead = 1;
1108                 status = 0;
1109         }
1110
1111         /* Does this device support retrieving a video ROM? */
1112         if (video->cap._ROM) {
1113                 video->flags.rom = 1;
1114                 status = 0;
1115         }
1116
1117         /* Does this device support configuring which video device to POST? */
1118         if (video->cap._GPD && video->cap._SPD && video->cap._VPO) {
1119                 video->flags.post = 1;
1120                 status = 0;
1121         }
1122
1123         return status;
1124 }
1125
1126 /*
1127  * --------------------------------------------------------------------------
1128  *                               Driver Interface
1129  * --------------------------------------------------------------------------
1130  */
1131
1132 /* device interface */
1133 static struct acpi_video_device_attrib *
1134 acpi_video_get_device_attr(struct acpi_video_bus *video, unsigned long device_id)
1135 {
1136         struct acpi_video_enumerated_device *ids;
1137         int i;
1138
1139         for (i = 0; i < video->attached_count; i++) {
1140                 ids = &video->attached_array[i];
1141                 if ((ids->value.int_val & 0xffff) == device_id)
1142                         return &ids->value.attrib;
1143         }
1144
1145         return NULL;
1146 }
1147
1148 static int
1149 acpi_video_get_device_type(struct acpi_video_bus *video,
1150                            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.int_val;
1159         }
1160
1161         return 0;
1162 }
1163
1164 static int
1165 acpi_video_bus_get_one_device(struct acpi_device *device,
1166                               struct acpi_video_bus *video)
1167 {
1168         unsigned long long device_id;
1169         int status, device_type;
1170         struct acpi_video_device *data;
1171         struct acpi_video_device_attrib *attribute;
1172
1173         status =
1174             acpi_evaluate_integer(device->handle, "_ADR", NULL, &device_id);
1175         /* Some device omits _ADR, we skip them instead of fail */
1176         if (ACPI_FAILURE(status))
1177                 return 0;
1178
1179         data = kzalloc(sizeof(struct acpi_video_device), GFP_KERNEL);
1180         if (!data)
1181                 return -ENOMEM;
1182
1183         strcpy(acpi_device_name(device), ACPI_VIDEO_DEVICE_NAME);
1184         strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
1185         device->driver_data = data;
1186
1187         data->device_id = device_id;
1188         data->video = video;
1189         data->dev = device;
1190         INIT_DELAYED_WORK(&data->switch_brightness_work,
1191                           acpi_video_switch_brightness);
1192
1193         attribute = acpi_video_get_device_attr(video, device_id);
1194
1195         if (attribute && (attribute->device_id_scheme || device_id_scheme)) {
1196                 switch (attribute->display_type) {
1197                 case ACPI_VIDEO_DISPLAY_CRT:
1198                         data->flags.crt = 1;
1199                         break;
1200                 case ACPI_VIDEO_DISPLAY_TV:
1201                         data->flags.tvout = 1;
1202                         break;
1203                 case ACPI_VIDEO_DISPLAY_DVI:
1204                         data->flags.dvi = 1;
1205                         break;
1206                 case ACPI_VIDEO_DISPLAY_LCD:
1207                         data->flags.lcd = 1;
1208                         break;
1209                 default:
1210                         data->flags.unknown = 1;
1211                         break;
1212                 }
1213                 if (attribute->bios_can_detect)
1214                         data->flags.bios = 1;
1215         } else {
1216                 /* Check for legacy IDs */
1217                 device_type = acpi_video_get_device_type(video, device_id);
1218                 /* Ignore bits 16 and 18-20 */
1219                 switch (device_type & 0xffe2ffff) {
1220                 case ACPI_VIDEO_DISPLAY_LEGACY_MONITOR:
1221                         data->flags.crt = 1;
1222                         break;
1223                 case ACPI_VIDEO_DISPLAY_LEGACY_PANEL:
1224                         data->flags.lcd = 1;
1225                         break;
1226                 case ACPI_VIDEO_DISPLAY_LEGACY_TV:
1227                         data->flags.tvout = 1;
1228                         break;
1229                 default:
1230                         data->flags.unknown = 1;
1231                 }
1232         }
1233
1234         acpi_video_device_bind(video, data);
1235         acpi_video_device_find_cap(data);
1236
1237         mutex_lock(&video->device_list_lock);
1238         list_add_tail(&data->entry, &video->video_device_list);
1239         mutex_unlock(&video->device_list_lock);
1240
1241         return status;
1242 }
1243
1244 /*
1245  *  Arg:
1246  *      video   : video bus device
1247  *
1248  *  Return:
1249  *      none
1250  *
1251  *  Enumerate the video device list of the video bus,
1252  *  bind the ids with the corresponding video devices
1253  *  under the video bus.
1254  */
1255
1256 static void acpi_video_device_rebind(struct acpi_video_bus *video)
1257 {
1258         struct acpi_video_device *dev;
1259
1260         mutex_lock(&video->device_list_lock);
1261
1262         list_for_each_entry(dev, &video->video_device_list, entry)
1263                 acpi_video_device_bind(video, dev);
1264
1265         mutex_unlock(&video->device_list_lock);
1266 }
1267
1268 /*
1269  *  Arg:
1270  *      video   : video bus device
1271  *      device  : video output device under the video
1272  *              bus
1273  *
1274  *  Return:
1275  *      none
1276  *
1277  *  Bind the ids with the corresponding video devices
1278  *  under the video bus.
1279  */
1280
1281 static void
1282 acpi_video_device_bind(struct acpi_video_bus *video,
1283                        struct acpi_video_device *device)
1284 {
1285         struct acpi_video_enumerated_device *ids;
1286         int i;
1287
1288         for (i = 0; i < video->attached_count; i++) {
1289                 ids = &video->attached_array[i];
1290                 if (device->device_id == (ids->value.int_val & 0xffff)) {
1291                         ids->bind_info = device;
1292                         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "device_bind %d\n", i));
1293                 }
1294         }
1295 }
1296
1297 static bool acpi_video_device_in_dod(struct acpi_video_device *device)
1298 {
1299         struct acpi_video_bus *video = device->video;
1300         int i;
1301
1302         /*
1303          * If we have a broken _DOD or we have more than 8 output devices
1304          * under the graphics controller node that we can't proper deal with
1305          * in the operation region code currently, no need to test.
1306          */
1307         if (!video->attached_count || video->child_count > 8)
1308                 return true;
1309
1310         for (i = 0; i < video->attached_count; i++) {
1311                 if ((video->attached_array[i].value.int_val & 0xfff) ==
1312                     (device->device_id & 0xfff))
1313                         return true;
1314         }
1315
1316         return false;
1317 }
1318
1319 /*
1320  *  Arg:
1321  *      video   : video bus device
1322  *
1323  *  Return:
1324  *      < 0     : error
1325  *
1326  *  Call _DOD to enumerate all devices attached to display adapter
1327  *
1328  */
1329
1330 static int acpi_video_device_enumerate(struct acpi_video_bus *video)
1331 {
1332         int status;
1333         int count;
1334         int i;
1335         struct acpi_video_enumerated_device *active_list;
1336         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1337         union acpi_object *dod = NULL;
1338         union acpi_object *obj;
1339
1340         if (!video->cap._DOD)
1341                 return AE_NOT_EXIST;
1342
1343         status = acpi_evaluate_object(video->device->handle, "_DOD", NULL, &buffer);
1344         if (!ACPI_SUCCESS(status)) {
1345                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _DOD"));
1346                 return status;
1347         }
1348
1349         dod = buffer.pointer;
1350         if (!dod || (dod->type != ACPI_TYPE_PACKAGE)) {
1351                 ACPI_EXCEPTION((AE_INFO, status, "Invalid _DOD data"));
1352                 status = -EFAULT;
1353                 goto out;
1354         }
1355
1356         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d video heads in _DOD\n",
1357                           dod->package.count));
1358
1359         active_list = kcalloc(1 + dod->package.count,
1360                               sizeof(struct acpi_video_enumerated_device),
1361                               GFP_KERNEL);
1362         if (!active_list) {
1363                 status = -ENOMEM;
1364                 goto out;
1365         }
1366
1367         count = 0;
1368         for (i = 0; i < dod->package.count; i++) {
1369                 obj = &dod->package.elements[i];
1370
1371                 if (obj->type != ACPI_TYPE_INTEGER) {
1372                         printk(KERN_ERR PREFIX
1373                                 "Invalid _DOD data in element %d\n", i);
1374                         continue;
1375                 }
1376
1377                 active_list[count].value.int_val = obj->integer.value;
1378                 active_list[count].bind_info = NULL;
1379                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "dod element[%d] = %d\n", i,
1380                                   (int)obj->integer.value));
1381                 count++;
1382         }
1383
1384         kfree(video->attached_array);
1385
1386         video->attached_array = active_list;
1387         video->attached_count = count;
1388
1389 out:
1390         kfree(buffer.pointer);
1391         return status;
1392 }
1393
1394 static int
1395 acpi_video_get_next_level(struct acpi_video_device *device,
1396                           u32 level_current, u32 event)
1397 {
1398         int min, max, min_above, max_below, i, l, delta = 255;
1399         max = max_below = 0;
1400         min = min_above = 255;
1401         /* Find closest level to level_current */
1402         for (i = ACPI_VIDEO_FIRST_LEVEL; i < device->brightness->count; i++) {
1403                 l = device->brightness->levels[i];
1404                 if (abs(l - level_current) < abs(delta)) {
1405                         delta = l - level_current;
1406                         if (!delta)
1407                                 break;
1408                 }
1409         }
1410         /* Ajust level_current to closest available level */
1411         level_current += delta;
1412         for (i = ACPI_VIDEO_FIRST_LEVEL; i < device->brightness->count; i++) {
1413                 l = device->brightness->levels[i];
1414                 if (l < min)
1415                         min = l;
1416                 if (l > max)
1417                         max = l;
1418                 if (l < min_above && l > level_current)
1419                         min_above = l;
1420                 if (l > max_below && l < level_current)
1421                         max_below = l;
1422         }
1423
1424         switch (event) {
1425         case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:
1426                 return (level_current < max) ? min_above : min;
1427         case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:
1428                 return (level_current < max) ? min_above : max;
1429         case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:
1430                 return (level_current > min) ? max_below : min;
1431         case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS:
1432         case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:
1433                 return 0;
1434         default:
1435                 return level_current;
1436         }
1437 }
1438
1439 static void
1440 acpi_video_switch_brightness(struct work_struct *work)
1441 {
1442         struct acpi_video_device *device = container_of(to_delayed_work(work),
1443                              struct acpi_video_device, switch_brightness_work);
1444         unsigned long long level_current, level_next;
1445         int event = device->switch_brightness_event;
1446         int result = -EINVAL;
1447
1448         /* no warning message if acpi_backlight=vendor or a quirk is used */
1449         if (!device->backlight)
1450                 return;
1451
1452         if (!device->brightness)
1453                 goto out;
1454
1455         result = acpi_video_device_lcd_get_level_current(device,
1456                                                          &level_current,
1457                                                          false);
1458         if (result)
1459                 goto out;
1460
1461         level_next = acpi_video_get_next_level(device, level_current, event);
1462
1463         result = acpi_video_device_lcd_set_level(device, level_next);
1464
1465         if (!result)
1466                 backlight_force_update(device->backlight,
1467                                        BACKLIGHT_UPDATE_HOTKEY);
1468
1469 out:
1470         if (result)
1471                 printk(KERN_ERR PREFIX "Failed to switch the brightness\n");
1472 }
1473
1474 int acpi_video_get_edid(struct acpi_device *device, int type, int device_id,
1475                         void **edid)
1476 {
1477         struct acpi_video_bus *video;
1478         struct acpi_video_device *video_device;
1479         union acpi_object *buffer = NULL;
1480         acpi_status status;
1481         int i, length;
1482
1483         if (!device || !acpi_driver_data(device))
1484                 return -EINVAL;
1485
1486         video = acpi_driver_data(device);
1487
1488         for (i = 0; i < video->attached_count; i++) {
1489                 video_device = video->attached_array[i].bind_info;
1490                 length = 256;
1491
1492                 if (!video_device)
1493                         continue;
1494
1495                 if (!video_device->cap._DDC)
1496                         continue;
1497
1498                 if (type) {
1499                         switch (type) {
1500                         case ACPI_VIDEO_DISPLAY_CRT:
1501                                 if (!video_device->flags.crt)
1502                                         continue;
1503                                 break;
1504                         case ACPI_VIDEO_DISPLAY_TV:
1505                                 if (!video_device->flags.tvout)
1506                                         continue;
1507                                 break;
1508                         case ACPI_VIDEO_DISPLAY_DVI:
1509                                 if (!video_device->flags.dvi)
1510                                         continue;
1511                                 break;
1512                         case ACPI_VIDEO_DISPLAY_LCD:
1513                                 if (!video_device->flags.lcd)
1514                                         continue;
1515                                 break;
1516                         }
1517                 } else if (video_device->device_id != device_id) {
1518                         continue;
1519                 }
1520
1521                 status = acpi_video_device_EDID(video_device, &buffer, length);
1522
1523                 if (ACPI_FAILURE(status) || !buffer ||
1524                     buffer->type != ACPI_TYPE_BUFFER) {
1525                         length = 128;
1526                         status = acpi_video_device_EDID(video_device, &buffer,
1527                                                         length);
1528                         if (ACPI_FAILURE(status) || !buffer ||
1529                             buffer->type != ACPI_TYPE_BUFFER) {
1530                                 continue;
1531                         }
1532                 }
1533
1534                 *edid = buffer->buffer.pointer;
1535                 return length;
1536         }
1537
1538         return -ENODEV;
1539 }
1540 EXPORT_SYMBOL(acpi_video_get_edid);
1541
1542 static int
1543 acpi_video_bus_get_devices(struct acpi_video_bus *video,
1544                            struct acpi_device *device)
1545 {
1546         int status = 0;
1547         struct acpi_device *dev;
1548
1549         /*
1550          * There are systems where video module known to work fine regardless
1551          * of broken _DOD and ignoring returned value here doesn't cause
1552          * any issues later.
1553          */
1554         acpi_video_device_enumerate(video);
1555
1556         list_for_each_entry(dev, &device->children, node) {
1557
1558                 status = acpi_video_bus_get_one_device(dev, video);
1559                 if (status) {
1560                         dev_err(&dev->dev, "Can't attach device\n");
1561                         break;
1562                 }
1563                 video->child_count++;
1564         }
1565         return status;
1566 }
1567
1568 /* acpi_video interface */
1569
1570 /*
1571  * Win8 requires setting bit2 of _DOS to let firmware know it shouldn't
1572  * preform any automatic brightness change on receiving a notification.
1573  */
1574 static int acpi_video_bus_start_devices(struct acpi_video_bus *video)
1575 {
1576         return acpi_video_bus_DOS(video, 0,
1577                                   acpi_osi_is_win8() ? 1 : 0);
1578 }
1579
1580 static int acpi_video_bus_stop_devices(struct acpi_video_bus *video)
1581 {
1582         return acpi_video_bus_DOS(video, 0,
1583                                   acpi_osi_is_win8() ? 0 : 1);
1584 }
1585
1586 static void acpi_video_bus_notify(struct acpi_device *device, u32 event)
1587 {
1588         struct acpi_video_bus *video = acpi_driver_data(device);
1589         struct input_dev *input;
1590         int keycode = 0;
1591
1592         if (!video || !video->input)
1593                 return;
1594
1595         input = video->input;
1596
1597         switch (event) {
1598         case ACPI_VIDEO_NOTIFY_SWITCH:  /* User requested a switch,
1599                                          * most likely via hotkey. */
1600                 keycode = KEY_SWITCHVIDEOMODE;
1601                 break;
1602
1603         case ACPI_VIDEO_NOTIFY_PROBE:   /* User plugged in or removed a video
1604                                          * connector. */
1605                 acpi_video_device_enumerate(video);
1606                 acpi_video_device_rebind(video);
1607                 keycode = KEY_SWITCHVIDEOMODE;
1608                 break;
1609
1610         case ACPI_VIDEO_NOTIFY_CYCLE:   /* Cycle Display output hotkey pressed. */
1611                 keycode = KEY_SWITCHVIDEOMODE;
1612                 break;
1613         case ACPI_VIDEO_NOTIFY_NEXT_OUTPUT:     /* Next Display output hotkey pressed. */
1614                 keycode = KEY_VIDEO_NEXT;
1615                 break;
1616         case ACPI_VIDEO_NOTIFY_PREV_OUTPUT:     /* previous Display output hotkey pressed. */
1617                 keycode = KEY_VIDEO_PREV;
1618                 break;
1619
1620         default:
1621                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1622                                   "Unsupported event [0x%x]\n", event));
1623                 break;
1624         }
1625
1626         if (acpi_notifier_call_chain(device, event, 0))
1627                 /* Something vetoed the keypress. */
1628                 keycode = 0;
1629
1630         if (keycode && (report_key_events & REPORT_OUTPUT_KEY_EVENTS)) {
1631                 input_report_key(input, keycode, 1);
1632                 input_sync(input);
1633                 input_report_key(input, keycode, 0);
1634                 input_sync(input);
1635         }
1636
1637         return;
1638 }
1639
1640 static void brightness_switch_event(struct acpi_video_device *video_device,
1641                                     u32 event)
1642 {
1643         if (!brightness_switch_enabled)
1644                 return;
1645
1646         video_device->switch_brightness_event = event;
1647         schedule_delayed_work(&video_device->switch_brightness_work, HZ / 10);
1648 }
1649
1650 static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data)
1651 {
1652         struct acpi_video_device *video_device = data;
1653         struct acpi_device *device = NULL;
1654         struct acpi_video_bus *bus;
1655         struct input_dev *input;
1656         int keycode = 0;
1657
1658         if (!video_device)
1659                 return;
1660
1661         device = video_device->dev;
1662         bus = video_device->video;
1663         input = bus->input;
1664
1665         if (hw_changes_brightness > 0) {
1666                 if (video_device->backlight)
1667                         backlight_force_update(video_device->backlight,
1668                                                BACKLIGHT_UPDATE_HOTKEY);
1669                 acpi_notifier_call_chain(device, event, 0);
1670                 return;
1671         }
1672
1673         switch (event) {
1674         case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:        /* Cycle brightness */
1675                 brightness_switch_event(video_device, event);
1676                 keycode = KEY_BRIGHTNESS_CYCLE;
1677                 break;
1678         case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:  /* Increase brightness */
1679                 brightness_switch_event(video_device, event);
1680                 keycode = KEY_BRIGHTNESSUP;
1681                 break;
1682         case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:  /* Decrease brightness */
1683                 brightness_switch_event(video_device, event);
1684                 keycode = KEY_BRIGHTNESSDOWN;
1685                 break;
1686         case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS: /* zero brightness */
1687                 brightness_switch_event(video_device, event);
1688                 keycode = KEY_BRIGHTNESS_ZERO;
1689                 break;
1690         case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:     /* display device off */
1691                 brightness_switch_event(video_device, event);
1692                 keycode = KEY_DISPLAY_OFF;
1693                 break;
1694         default:
1695                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1696                                   "Unsupported event [0x%x]\n", event));
1697                 break;
1698         }
1699
1700         acpi_notifier_call_chain(device, event, 0);
1701
1702         if (keycode && (report_key_events & REPORT_BRIGHTNESS_KEY_EVENTS)) {
1703                 input_report_key(input, keycode, 1);
1704                 input_sync(input);
1705                 input_report_key(input, keycode, 0);
1706                 input_sync(input);
1707         }
1708
1709         return;
1710 }
1711
1712 static int acpi_video_resume(struct notifier_block *nb,
1713                                 unsigned long val, void *ign)
1714 {
1715         struct acpi_video_bus *video;
1716         struct acpi_video_device *video_device;
1717         int i;
1718
1719         switch (val) {
1720         case PM_HIBERNATION_PREPARE:
1721         case PM_SUSPEND_PREPARE:
1722         case PM_RESTORE_PREPARE:
1723                 return NOTIFY_DONE;
1724         }
1725
1726         video = container_of(nb, struct acpi_video_bus, pm_nb);
1727
1728         dev_info(&video->device->dev, "Restoring backlight state\n");
1729
1730         for (i = 0; i < video->attached_count; i++) {
1731                 video_device = video->attached_array[i].bind_info;
1732                 if (video_device && video_device->brightness)
1733                         acpi_video_device_lcd_set_level(video_device,
1734                                         video_device->brightness->curr);
1735         }
1736
1737         return NOTIFY_OK;
1738 }
1739
1740 static acpi_status
1741 acpi_video_bus_match(acpi_handle handle, u32 level, void *context,
1742                         void **return_value)
1743 {
1744         struct acpi_device *device = context;
1745         struct acpi_device *sibling;
1746         int result;
1747
1748         if (handle == device->handle)
1749                 return AE_CTRL_TERMINATE;
1750
1751         result = acpi_bus_get_device(handle, &sibling);
1752         if (result)
1753                 return AE_OK;
1754
1755         if (!strcmp(acpi_device_name(sibling), ACPI_VIDEO_BUS_NAME))
1756                         return AE_ALREADY_EXISTS;
1757
1758         return AE_OK;
1759 }
1760
1761 static void acpi_video_dev_register_backlight(struct acpi_video_device *device)
1762 {
1763         struct backlight_properties props;
1764         struct pci_dev *pdev;
1765         acpi_handle acpi_parent;
1766         struct device *parent = NULL;
1767         int result;
1768         static int count;
1769         char *name;
1770
1771         result = acpi_video_init_brightness(device);
1772         if (result)
1773                 return;
1774
1775         if (disable_backlight_sysfs_if > 0)
1776                 return;
1777
1778         name = kasprintf(GFP_KERNEL, "acpi_video%d", count);
1779         if (!name)
1780                 return;
1781         count++;
1782
1783         acpi_get_parent(device->dev->handle, &acpi_parent);
1784
1785         pdev = acpi_get_pci_dev(acpi_parent);
1786         if (pdev) {
1787                 parent = &pdev->dev;
1788                 pci_dev_put(pdev);
1789         }
1790
1791         memset(&props, 0, sizeof(struct backlight_properties));
1792         props.type = BACKLIGHT_FIRMWARE;
1793         props.max_brightness =
1794                 device->brightness->count - ACPI_VIDEO_FIRST_LEVEL - 1;
1795         device->backlight = backlight_device_register(name,
1796                                                       parent,
1797                                                       device,
1798                                                       &acpi_backlight_ops,
1799                                                       &props);
1800         kfree(name);
1801         if (IS_ERR(device->backlight)) {
1802                 device->backlight = NULL;
1803                 return;
1804         }
1805
1806         /*
1807          * Save current brightness level in case we have to restore it
1808          * before acpi_video_device_lcd_set_level() is called next time.
1809          */
1810         device->backlight->props.brightness =
1811                         acpi_video_get_brightness(device->backlight);
1812
1813         device->cooling_dev = thermal_cooling_device_register("LCD",
1814                                 device->dev, &video_cooling_ops);
1815         if (IS_ERR(device->cooling_dev)) {
1816                 /*
1817                  * Set cooling_dev to NULL so we don't crash trying to free it.
1818                  * Also, why the hell we are returning early and not attempt to
1819                  * register video output if cooling device registration failed?
1820                  * -- dtor
1821                  */
1822                 device->cooling_dev = NULL;
1823                 return;
1824         }
1825
1826         dev_info(&device->dev->dev, "registered as cooling_device%d\n",
1827                  device->cooling_dev->id);
1828         result = sysfs_create_link(&device->dev->dev.kobj,
1829                         &device->cooling_dev->device.kobj,
1830                         "thermal_cooling");
1831         if (result)
1832                 printk(KERN_ERR PREFIX "Create sysfs link\n");
1833         result = sysfs_create_link(&device->cooling_dev->device.kobj,
1834                         &device->dev->dev.kobj, "device");
1835         if (result)
1836                 printk(KERN_ERR PREFIX "Create sysfs link\n");
1837 }
1838
1839 static void acpi_video_run_bcl_for_osi(struct acpi_video_bus *video)
1840 {
1841         struct acpi_video_device *dev;
1842         union acpi_object *levels;
1843
1844         mutex_lock(&video->device_list_lock);
1845         list_for_each_entry(dev, &video->video_device_list, entry) {
1846                 if (!acpi_video_device_lcd_query_levels(dev->dev->handle, &levels))
1847                         kfree(levels);
1848         }
1849         mutex_unlock(&video->device_list_lock);
1850 }
1851
1852 static bool acpi_video_should_register_backlight(struct acpi_video_device *dev)
1853 {
1854         /*
1855          * Do not create backlight device for video output
1856          * device that is not in the enumerated list.
1857          */
1858         if (!acpi_video_device_in_dod(dev)) {
1859                 dev_dbg(&dev->dev->dev, "not in _DOD list, ignore\n");
1860                 return false;
1861         }
1862
1863         if (only_lcd)
1864                 return dev->flags.lcd;
1865         return true;
1866 }
1867
1868 static int acpi_video_bus_register_backlight(struct acpi_video_bus *video)
1869 {
1870         struct acpi_video_device *dev;
1871
1872         if (video->backlight_registered)
1873                 return 0;
1874
1875         acpi_video_run_bcl_for_osi(video);
1876
1877         if (acpi_video_get_backlight_type() != acpi_backlight_video)
1878                 return 0;
1879
1880         mutex_lock(&video->device_list_lock);
1881         list_for_each_entry(dev, &video->video_device_list, entry) {
1882                 if (acpi_video_should_register_backlight(dev))
1883                         acpi_video_dev_register_backlight(dev);
1884         }
1885         mutex_unlock(&video->device_list_lock);
1886
1887         video->backlight_registered = true;
1888
1889         video->pm_nb.notifier_call = acpi_video_resume;
1890         video->pm_nb.priority = 0;
1891         return register_pm_notifier(&video->pm_nb);
1892 }
1893
1894 static void acpi_video_dev_unregister_backlight(struct acpi_video_device *device)
1895 {
1896         if (device->backlight) {
1897                 backlight_device_unregister(device->backlight);
1898                 device->backlight = NULL;
1899         }
1900         if (device->brightness) {
1901                 kfree(device->brightness->levels);
1902                 kfree(device->brightness);
1903                 device->brightness = NULL;
1904         }
1905         if (device->cooling_dev) {
1906                 sysfs_remove_link(&device->dev->dev.kobj, "thermal_cooling");
1907                 sysfs_remove_link(&device->cooling_dev->device.kobj, "device");
1908                 thermal_cooling_device_unregister(device->cooling_dev);
1909                 device->cooling_dev = NULL;
1910         }
1911 }
1912
1913 static int acpi_video_bus_unregister_backlight(struct acpi_video_bus *video)
1914 {
1915         struct acpi_video_device *dev;
1916         int error;
1917
1918         if (!video->backlight_registered)
1919                 return 0;
1920
1921         error = unregister_pm_notifier(&video->pm_nb);
1922
1923         mutex_lock(&video->device_list_lock);
1924         list_for_each_entry(dev, &video->video_device_list, entry)
1925                 acpi_video_dev_unregister_backlight(dev);
1926         mutex_unlock(&video->device_list_lock);
1927
1928         video->backlight_registered = false;
1929
1930         return error;
1931 }
1932
1933 static void acpi_video_dev_add_notify_handler(struct acpi_video_device *device)
1934 {
1935         acpi_status status;
1936         struct acpi_device *adev = device->dev;
1937
1938         status = acpi_install_notify_handler(adev->handle, ACPI_DEVICE_NOTIFY,
1939                                              acpi_video_device_notify, device);
1940         if (ACPI_FAILURE(status))
1941                 dev_err(&adev->dev, "Error installing notify handler\n");
1942         else
1943                 device->flags.notify = 1;
1944 }
1945
1946 static int acpi_video_bus_add_notify_handler(struct acpi_video_bus *video)
1947 {
1948         struct input_dev *input;
1949         struct acpi_video_device *dev;
1950         int error;
1951
1952         video->input = input = input_allocate_device();
1953         if (!input) {
1954                 error = -ENOMEM;
1955                 goto out;
1956         }
1957
1958         error = acpi_video_bus_start_devices(video);
1959         if (error)
1960                 goto err_free_input;
1961
1962         snprintf(video->phys, sizeof(video->phys),
1963                         "%s/video/input0", acpi_device_hid(video->device));
1964
1965         input->name = acpi_device_name(video->device);
1966         input->phys = video->phys;
1967         input->id.bustype = BUS_HOST;
1968         input->id.product = 0x06;
1969         input->dev.parent = &video->device->dev;
1970         input->evbit[0] = BIT(EV_KEY);
1971         set_bit(KEY_SWITCHVIDEOMODE, input->keybit);
1972         set_bit(KEY_VIDEO_NEXT, input->keybit);
1973         set_bit(KEY_VIDEO_PREV, input->keybit);
1974         set_bit(KEY_BRIGHTNESS_CYCLE, input->keybit);
1975         set_bit(KEY_BRIGHTNESSUP, input->keybit);
1976         set_bit(KEY_BRIGHTNESSDOWN, input->keybit);
1977         set_bit(KEY_BRIGHTNESS_ZERO, input->keybit);
1978         set_bit(KEY_DISPLAY_OFF, input->keybit);
1979
1980         error = input_register_device(input);
1981         if (error)
1982                 goto err_stop_dev;
1983
1984         mutex_lock(&video->device_list_lock);
1985         list_for_each_entry(dev, &video->video_device_list, entry)
1986                 acpi_video_dev_add_notify_handler(dev);
1987         mutex_unlock(&video->device_list_lock);
1988
1989         return 0;
1990
1991 err_stop_dev:
1992         acpi_video_bus_stop_devices(video);
1993 err_free_input:
1994         input_free_device(input);
1995         video->input = NULL;
1996 out:
1997         return error;
1998 }
1999
2000 static void acpi_video_dev_remove_notify_handler(struct acpi_video_device *dev)
2001 {
2002         if (dev->flags.notify) {
2003                 acpi_remove_notify_handler(dev->dev->handle, ACPI_DEVICE_NOTIFY,
2004                                            acpi_video_device_notify);
2005                 dev->flags.notify = 0;
2006         }
2007 }
2008
2009 static void acpi_video_bus_remove_notify_handler(struct acpi_video_bus *video)
2010 {
2011         struct acpi_video_device *dev;
2012
2013         mutex_lock(&video->device_list_lock);
2014         list_for_each_entry(dev, &video->video_device_list, entry)
2015                 acpi_video_dev_remove_notify_handler(dev);
2016         mutex_unlock(&video->device_list_lock);
2017
2018         acpi_video_bus_stop_devices(video);
2019         input_unregister_device(video->input);
2020         video->input = NULL;
2021 }
2022
2023 static int acpi_video_bus_put_devices(struct acpi_video_bus *video)
2024 {
2025         struct acpi_video_device *dev, *next;
2026
2027         mutex_lock(&video->device_list_lock);
2028         list_for_each_entry_safe(dev, next, &video->video_device_list, entry) {
2029                 list_del(&dev->entry);
2030                 kfree(dev);
2031         }
2032         mutex_unlock(&video->device_list_lock);
2033
2034         return 0;
2035 }
2036
2037 static int instance;
2038
2039 static int acpi_video_bus_add(struct acpi_device *device)
2040 {
2041         struct acpi_video_bus *video;
2042         int error;
2043         acpi_status status;
2044
2045         status = acpi_walk_namespace(ACPI_TYPE_DEVICE,
2046                                 device->parent->handle, 1,
2047                                 acpi_video_bus_match, NULL,
2048                                 device, NULL);
2049         if (status == AE_ALREADY_EXISTS) {
2050                 printk(KERN_WARNING FW_BUG
2051                         "Duplicate ACPI video bus devices for the"
2052                         " same VGA controller, please try module "
2053                         "parameter \"video.allow_duplicates=1\""
2054                         "if the current driver doesn't work.\n");
2055                 if (!allow_duplicates)
2056                         return -ENODEV;
2057         }
2058
2059         video = kzalloc(sizeof(struct acpi_video_bus), GFP_KERNEL);
2060         if (!video)
2061                 return -ENOMEM;
2062
2063         /* a hack to fix the duplicate name "VID" problem on T61 */
2064         if (!strcmp(device->pnp.bus_id, "VID")) {
2065                 if (instance)
2066                         device->pnp.bus_id[3] = '0' + instance;
2067                 instance++;
2068         }
2069         /* a hack to fix the duplicate name "VGA" problem on Pa 3553 */
2070         if (!strcmp(device->pnp.bus_id, "VGA")) {
2071                 if (instance)
2072                         device->pnp.bus_id[3] = '0' + instance;
2073                 instance++;
2074         }
2075
2076         video->device = device;
2077         strcpy(acpi_device_name(device), ACPI_VIDEO_BUS_NAME);
2078         strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
2079         device->driver_data = video;
2080
2081         acpi_video_bus_find_cap(video);
2082         error = acpi_video_bus_check(video);
2083         if (error)
2084                 goto err_free_video;
2085
2086         mutex_init(&video->device_list_lock);
2087         INIT_LIST_HEAD(&video->video_device_list);
2088
2089         error = acpi_video_bus_get_devices(video, device);
2090         if (error)
2091                 goto err_put_video;
2092
2093         printk(KERN_INFO PREFIX "%s [%s] (multi-head: %s  rom: %s  post: %s)\n",
2094                ACPI_VIDEO_DEVICE_NAME, acpi_device_bid(device),
2095                video->flags.multihead ? "yes" : "no",
2096                video->flags.rom ? "yes" : "no",
2097                video->flags.post ? "yes" : "no");
2098         mutex_lock(&video_list_lock);
2099         list_add_tail(&video->entry, &video_bus_head);
2100         mutex_unlock(&video_list_lock);
2101
2102         acpi_video_bus_register_backlight(video);
2103         acpi_video_bus_add_notify_handler(video);
2104
2105         return 0;
2106
2107 err_put_video:
2108         acpi_video_bus_put_devices(video);
2109         kfree(video->attached_array);
2110 err_free_video:
2111         kfree(video);
2112         device->driver_data = NULL;
2113
2114         return error;
2115 }
2116
2117 static int acpi_video_bus_remove(struct acpi_device *device)
2118 {
2119         struct acpi_video_bus *video = NULL;
2120
2121
2122         if (!device || !acpi_driver_data(device))
2123                 return -EINVAL;
2124
2125         video = acpi_driver_data(device);
2126
2127         acpi_video_bus_remove_notify_handler(video);
2128         acpi_video_bus_unregister_backlight(video);
2129         acpi_video_bus_put_devices(video);
2130
2131         mutex_lock(&video_list_lock);
2132         list_del(&video->entry);
2133         mutex_unlock(&video_list_lock);
2134
2135         kfree(video->attached_array);
2136         kfree(video);
2137
2138         return 0;
2139 }
2140
2141 static int __init is_i740(struct pci_dev *dev)
2142 {
2143         if (dev->device == 0x00D1)
2144                 return 1;
2145         if (dev->device == 0x7000)
2146                 return 1;
2147         return 0;
2148 }
2149
2150 static int __init intel_opregion_present(void)
2151 {
2152         int opregion = 0;
2153         struct pci_dev *dev = NULL;
2154         u32 address;
2155
2156         for_each_pci_dev(dev) {
2157                 if ((dev->class >> 8) != PCI_CLASS_DISPLAY_VGA)
2158                         continue;
2159                 if (dev->vendor != PCI_VENDOR_ID_INTEL)
2160                         continue;
2161                 /* We don't want to poke around undefined i740 registers */
2162                 if (is_i740(dev))
2163                         continue;
2164                 pci_read_config_dword(dev, 0xfc, &address);
2165                 if (!address)
2166                         continue;
2167                 opregion = 1;
2168         }
2169         return opregion;
2170 }
2171
2172 /* Check if the chassis-type indicates there is no builtin LCD panel */
2173 static bool dmi_is_desktop(void)
2174 {
2175         const char *chassis_type;
2176         unsigned long type;
2177
2178         chassis_type = dmi_get_system_info(DMI_CHASSIS_TYPE);
2179         if (!chassis_type)
2180                 return false;
2181
2182         if (kstrtoul(chassis_type, 10, &type) != 0)
2183                 return false;
2184
2185         switch (type) {
2186         case 0x03: /* Desktop */
2187         case 0x04: /* Low Profile Desktop */
2188         case 0x05: /* Pizza Box */
2189         case 0x06: /* Mini Tower */
2190         case 0x07: /* Tower */
2191         case 0x10: /* Lunch Box */
2192         case 0x11: /* Main Server Chassis */
2193                 return true;
2194         }
2195
2196         return false;
2197 }
2198
2199 int acpi_video_register(void)
2200 {
2201         int ret = 0;
2202
2203         mutex_lock(&register_count_mutex);
2204         if (register_count) {
2205                 /*
2206                  * if the function of acpi_video_register is already called,
2207                  * don't register the acpi_vide_bus again and return no error.
2208                  */
2209                 goto leave;
2210         }
2211
2212         /*
2213          * We're seeing a lot of bogus backlight interfaces on newer machines
2214          * without a LCD such as desktops, servers and HDMI sticks. Checking
2215          * the lcd flag fixes this, so enable this on any machines which are
2216          * win8 ready (where we also prefer the native backlight driver, so
2217          * normally the acpi_video code should not register there anyways).
2218          */
2219         if (only_lcd == -1) {
2220                 if (dmi_is_desktop() && acpi_osi_is_win8())
2221                         only_lcd = true;
2222                 else
2223                         only_lcd = false;
2224         }
2225
2226         dmi_check_system(video_dmi_table);
2227
2228         ret = acpi_bus_register_driver(&acpi_video_bus);
2229         if (ret)
2230                 goto leave;
2231
2232         /*
2233          * When the acpi_video_bus is loaded successfully, increase
2234          * the counter reference.
2235          */
2236         register_count = 1;
2237
2238 leave:
2239         mutex_unlock(&register_count_mutex);
2240         return ret;
2241 }
2242 EXPORT_SYMBOL(acpi_video_register);
2243
2244 void acpi_video_unregister(void)
2245 {
2246         mutex_lock(&register_count_mutex);
2247         if (register_count) {
2248                 acpi_bus_unregister_driver(&acpi_video_bus);
2249                 register_count = 0;
2250         }
2251         mutex_unlock(&register_count_mutex);
2252 }
2253 EXPORT_SYMBOL(acpi_video_unregister);
2254
2255 void acpi_video_unregister_backlight(void)
2256 {
2257         struct acpi_video_bus *video;
2258
2259         mutex_lock(&register_count_mutex);
2260         if (register_count) {
2261                 mutex_lock(&video_list_lock);
2262                 list_for_each_entry(video, &video_bus_head, entry)
2263                         acpi_video_bus_unregister_backlight(video);
2264                 mutex_unlock(&video_list_lock);
2265         }
2266         mutex_unlock(&register_count_mutex);
2267 }
2268
2269 bool acpi_video_handles_brightness_key_presses(void)
2270 {
2271         bool have_video_busses;
2272
2273         mutex_lock(&video_list_lock);
2274         have_video_busses = !list_empty(&video_bus_head);
2275         mutex_unlock(&video_list_lock);
2276
2277         return have_video_busses &&
2278                (report_key_events & REPORT_BRIGHTNESS_KEY_EVENTS);
2279 }
2280 EXPORT_SYMBOL(acpi_video_handles_brightness_key_presses);
2281
2282 /*
2283  * This is kind of nasty. Hardware using Intel chipsets may require
2284  * the video opregion code to be run first in order to initialise
2285  * state before any ACPI video calls are made. To handle this we defer
2286  * registration of the video class until the opregion code has run.
2287  */
2288
2289 static int __init acpi_video_init(void)
2290 {
2291         /*
2292          * Let the module load even if ACPI is disabled (e.g. due to
2293          * a broken BIOS) so that i915.ko can still be loaded on such
2294          * old systems without an AcpiOpRegion.
2295          *
2296          * acpi_video_register() will report -ENODEV later as well due
2297          * to acpi_disabled when i915.ko tries to register itself afterwards.
2298          */
2299         if (acpi_disabled)
2300                 return 0;
2301
2302         if (intel_opregion_present())
2303                 return 0;
2304
2305         return acpi_video_register();
2306 }
2307
2308 static void __exit acpi_video_exit(void)
2309 {
2310         acpi_video_detect_exit();
2311         acpi_video_unregister();
2312
2313         return;
2314 }
2315
2316 module_init(acpi_video_init);
2317 module_exit(acpi_video_exit);