drivers/acpi/acpi_video.c

   1 /*
   2  *  video.c - ACPI Video Driver
   3  *
   4  *  Copyright (C) 2004 Luming Yu <luming.yu@intel.com>
   5  *  Copyright (C) 2004 Bruno Ducrot <ducrot@poupinou.org>
   6  *  Copyright (C) 2006 Thomas Tuttle <linux-kernel@ttuttle.net>
   7  *
   8  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   9  *
  10  *  This program is free software; you can redistribute it and/or modify
  11  *  it under the terms of the GNU General Public License as published by
  12  *  the Free Software Foundation; either version 2 of the License, or (at
  13  *  your option) any later version.
  14  *
  15  *  This program is distributed in the hope that it will be useful, but
  16  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  17  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  *  General Public License for more details.
  19  *
  20  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  21  */
  22
  23 #include <linux/kernel.h>
  24 #include <linux/module.h>
  25 #include <linux/init.h>
  26 #include <linux/types.h>
  27 #include <linux/list.h>
  28 #include <linux/mutex.h>
  29 #include <linux/input.h>
  30 #include <linux/backlight.h>
  31 #include <linux/thermal.h>
  32 #include <linux/sort.h>
  33 #include <linux/pci.h>
  34 #include <linux/pci_ids.h>
  35 #include <linux/slab.h>
  36 #include <linux/dmi.h>
  37 #include <linux/suspend.h>
  38 #include <linux/acpi.h>
  39 #include <acpi/video.h>
  40 #include <linux/uaccess.h>
  41
  42 #define PREFIX "ACPI: "
  43
  44 #define ACPI_VIDEO_BUS_NAME             "Video Bus"
  45 #define ACPI_VIDEO_DEVICE_NAME          "Video Device"
  46
  47 #define MAX_NAME_LEN    20
  48
  49 #define _COMPONENT              ACPI_VIDEO_COMPONENT
  50 ACPI_MODULE_NAME("video");
  51
  52 MODULE_AUTHOR("Bruno Ducrot");
  53 MODULE_DESCRIPTION("ACPI Video Driver");
  54 MODULE_LICENSE("GPL");
  55
  56 static bool brightness_switch_enabled = true;
  57 module_param(brightness_switch_enabled, bool, 0644);
  58
  59 /*
  60  * By default, we don't allow duplicate ACPI video bus devices
  61  * under the same VGA controller
  62  */
  63 static bool allow_duplicates;
  64 module_param(allow_duplicates, bool, 0644);
  65
  66 static int disable_backlight_sysfs_if = -1;
  67 module_param(disable_backlight_sysfs_if, int, 0444);
  68
  69 #define REPORT_OUTPUT_KEY_EVENTS                0x01
  70 #define REPORT_BRIGHTNESS_KEY_EVENTS            0x02
  71 static int report_key_events = -1;
  72 module_param(report_key_events, int, 0644);
  73 MODULE_PARM_DESC(report_key_events,
  74         "0: none, 1: output changes, 2: brightness changes, 3: all");
  75
  76 static int hw_changes_brightness = -1;
  77 module_param(hw_changes_brightness, int, 0644);
  78 MODULE_PARM_DESC(hw_changes_brightness,
  79         "Set this to 1 on buggy hw which changes the brightness itself when "
  80         "a hotkey is pressed: -1: auto, 0: normal 1: hw-changes-brightness");
  81
  82 /*
  83  * Whether the struct acpi_video_device_attrib::device_id_scheme bit should be
  84  * assumed even if not actually set.
  85  */
  86 static bool device_id_scheme = false;
  87 module_param(device_id_scheme, bool, 0444);
  88
  89 static int only_lcd = -1;
  90 module_param(only_lcd, int, 0444);
  91
  92 static int register_count;
  93 static DEFINE_MUTEX(register_count_mutex);
  94 static DEFINE_MUTEX(video_list_lock);
  95 static LIST_HEAD(video_bus_head);
  96 static int acpi_video_bus_add(struct acpi_device *device);
  97 static int acpi_video_bus_remove(struct acpi_device *device);
  98 static void acpi_video_bus_notify(struct acpi_device *device, u32 event);
  99 void acpi_video_detect_exit(void);
 100
 101 /*
 102  * Indices in the _BCL method response: the first two items are special,
 103  * the rest are all supported levels.
 104  *
 105  * See page 575 of the ACPI spec 3.0
 106  */
 107 enum acpi_video_level_idx {
 108         ACPI_VIDEO_AC_LEVEL,            /* level when machine has full power */
 109         ACPI_VIDEO_BATTERY_LEVEL,       /* level when machine is on batteries */
 110         ACPI_VIDEO_FIRST_LEVEL,         /* actual supported levels begin here */
 111 };
 112
 113 static const struct acpi_device_id video_device_ids[] = {
 114         {ACPI_VIDEO_HID, 0},
 115         {"", 0},
 116 };
 117 MODULE_DEVICE_TABLE(acpi, video_device_ids);
 118
 119 static struct acpi_driver acpi_video_bus = {
 120         .name = "video",
 121         .class = ACPI_VIDEO_CLASS,
 122         .ids = video_device_ids,
 123         .ops = {
 124                 .add = acpi_video_bus_add,
 125                 .remove = acpi_video_bus_remove,
 126                 .notify = acpi_video_bus_notify,
 127                 },
 128 };
 129
 130 struct acpi_video_bus_flags {
 131         u8 multihead:1;         /* can switch video heads */
 132         u8 rom:1;               /* can retrieve a video rom */
 133         u8 post:1;              /* can configure the head to */
 134         u8 reserved:5;
 135 };
 136
 137 struct acpi_video_bus_cap {
 138         u8 _DOS:1;              /* Enable/Disable output switching */
 139         u8 _DOD:1;              /* Enumerate all devices attached to display adapter */
 140         u8 _ROM:1;              /* Get ROM Data */
 141         u8 _GPD:1;              /* Get POST Device */
 142         u8 _SPD:1;              /* Set POST Device */
 143         u8 _VPO:1;              /* Video POST Options */
 144         u8 reserved:2;
 145 };
 146
 147 struct acpi_video_device_attrib {
 148         u32 display_index:4;    /* A zero-based instance of the Display */
 149         u32 display_port_attachment:4;  /* This field differentiates the display type */
 150         u32 display_type:4;     /* Describe the specific type in use */
 151         u32 vendor_specific:4;  /* Chipset Vendor Specific */
 152         u32 bios_can_detect:1;  /* BIOS can detect the device */
 153         u32 depend_on_vga:1;    /* Non-VGA output device whose power is related to
 154                                    the VGA device. */
 155         u32 pipe_id:3;          /* For VGA multiple-head devices. */
 156         u32 reserved:10;        /* Must be 0 */
 157
 158         /*
 159          * The device ID might not actually follow the scheme described by this
 160          * struct acpi_video_device_attrib. If it does, then this bit
 161          * device_id_scheme is set; otherwise, other fields should be ignored.
 162          *
 163          * (but also see the global flag device_id_scheme)
 164          */
 165         u32 device_id_scheme:1;
 166 };
 167
 168 struct acpi_video_enumerated_device {
 169         union {
 170                 u32 int_val;
 171                 struct acpi_video_device_attrib attrib;
 172         } value;
 173         struct acpi_video_device *bind_info;
 174 };
 175
 176 struct acpi_video_bus {
 177         struct acpi_device *device;
 178         bool backlight_registered;
 179         u8 dos_setting;
 180         struct acpi_video_enumerated_device *attached_array;
 181         u8 attached_count;
 182         u8 child_count;
 183         struct acpi_video_bus_cap cap;
 184         struct acpi_video_bus_flags flags;
 185         struct list_head video_device_list;
 186         struct mutex device_list_lock;  /* protects video_device_list */
 187         struct list_head entry;
 188         struct input_dev *input;
 189         char phys[32];  /* for input device */
 190         struct notifier_block pm_nb;
 191 };
 192
 193 struct acpi_video_device_flags {
 194         u8 crt:1;
 195         u8 lcd:1;
 196         u8 tvout:1;
 197         u8 dvi:1;
 198         u8 bios:1;
 199         u8 unknown:1;
 200         u8 notify:1;
 201         u8 reserved:1;
 202 };
 203
 204 struct acpi_video_device_cap {
 205         u8 _ADR:1;              /* Return the unique ID */
 206         u8 _BCL:1;              /* Query list of brightness control levels supported */
 207         u8 _BCM:1;              /* Set the brightness level */
 208         u8 _BQC:1;              /* Get current brightness level */
 209         u8 _BCQ:1;              /* Some buggy BIOS uses _BCQ instead of _BQC */
 210         u8 _DDC:1;              /* Return the EDID for this device */
 211 };
 212
 213 struct acpi_video_device {
 214         unsigned long device_id;
 215         struct acpi_video_device_flags flags;
 216         struct acpi_video_device_cap cap;
 217         struct list_head entry;
 218         struct delayed_work switch_brightness_work;
 219         int switch_brightness_event;
 220         struct acpi_video_bus *video;
 221         struct acpi_device *dev;
 222         struct acpi_video_device_brightness *brightness;
 223         struct backlight_device *backlight;
 224         struct thermal_cooling_device *cooling_dev;
 225 };
 226
 227 static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data);
 228 static void acpi_video_device_rebind(struct acpi_video_bus *video);
 229 static void acpi_video_device_bind(struct acpi_video_bus *video,
 230                                    struct acpi_video_device *device);
 231 static int acpi_video_device_enumerate(struct acpi_video_bus *video);
 232 static int acpi_video_device_lcd_set_level(struct acpi_video_device *device,
 233                         int level);
 234 static int acpi_video_device_lcd_get_level_current(
 235                         struct acpi_video_device *device,
 236                         unsigned long long *level, bool raw);
 237 static int acpi_video_get_next_level(struct acpi_video_device *device,
 238                                      u32 level_current, u32 event);
 239 static void acpi_video_switch_brightness(struct work_struct *work);
 240
 241 /* backlight device sysfs support */
 242 static int acpi_video_get_brightness(struct backlight_device *bd)
 243 {
 244         unsigned long long cur_level;
 245         int i;
 246         struct acpi_video_device *vd = bl_get_data(bd);
 247
 248         if (acpi_video_device_lcd_get_level_current(vd, &cur_level, false))
 249                 return -EINVAL;
 250         for (i = ACPI_VIDEO_FIRST_LEVEL; i < vd->brightness->count; i++) {
 251                 if (vd->brightness->levels[i] == cur_level)
 252                         return i - ACPI_VIDEO_FIRST_LEVEL;
 253         }
 254         return 0;
 255 }
 256
 257 static int acpi_video_set_brightness(struct backlight_device *bd)
 258 {
 259         int request_level = bd->props.brightness + ACPI_VIDEO_FIRST_LEVEL;
 260         struct acpi_video_device *vd = bl_get_data(bd);
 261
 262         cancel_delayed_work(&vd->switch_brightness_work);
 263         return acpi_video_device_lcd_set_level(vd,
 264                                 vd->brightness->levels[request_level]);
 265 }
 266
 267 static const struct backlight_ops acpi_backlight_ops = {
 268         .get_brightness = acpi_video_get_brightness,
 269         .update_status  = acpi_video_set_brightness,
 270 };
 271
 272 /* thermal cooling device callbacks */
 273 static int video_get_max_state(struct thermal_cooling_device *cooling_dev,
 274                                unsigned long *state)
 275 {
 276         struct acpi_device *device = cooling_dev->devdata;
 277         struct acpi_video_device *video = acpi_driver_data(device);
 278
 279         *state = video->brightness->count - ACPI_VIDEO_FIRST_LEVEL - 1;
 280         return 0;
 281 }
 282
 283 static int video_get_cur_state(struct thermal_cooling_device *cooling_dev,
 284                                unsigned long *state)
 285 {
 286         struct acpi_device *device = cooling_dev->devdata;
 287         struct acpi_video_device *video = acpi_driver_data(device);
 288         unsigned long long level;
 289         int offset;
 290
 291         if (acpi_video_device_lcd_get_level_current(video, &level, false))
 292                 return -EINVAL;
 293         for (offset = ACPI_VIDEO_FIRST_LEVEL; offset < video->brightness->count;
 294              offset++)
 295                 if (level == video->brightness->levels[offset]) {
 296                         *state = video->brightness->count - offset - 1;
 297                         return 0;
 298                 }
 299
 300         return -EINVAL;
 301 }
 302
 303 static int
 304 video_set_cur_state(struct thermal_cooling_device *cooling_dev, unsigned long state)
 305 {
 306         struct acpi_device *device = cooling_dev->devdata;
 307         struct acpi_video_device *video = acpi_driver_data(device);
 308         int level;
 309
 310         if (state >= video->brightness->count - ACPI_VIDEO_FIRST_LEVEL)
 311                 return -EINVAL;
 312
 313         state = video->brightness->count - state;
 314         level = video->brightness->levels[state - 1];
 315         return acpi_video_device_lcd_set_level(video, level);
 316 }
 317
 318 static const struct thermal_cooling_device_ops video_cooling_ops = {
 319         .get_max_state = video_get_max_state,
 320         .get_cur_state = video_get_cur_state,
 321         .set_cur_state = video_set_cur_state,
 322 };
 323
 324 /*
 325  * --------------------------------------------------------------------------
 326  *                             Video Management
 327  * --------------------------------------------------------------------------
 328  */
 329
 330 static int
 331 acpi_video_device_lcd_query_levels(acpi_handle handle,
 332                                    union acpi_object **levels)
 333 {
 334         int status;
 335         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 336         union acpi_object *obj;
 337
 338
 339         *levels = NULL;
 340
 341         status = acpi_evaluate_object(handle, "_BCL", NULL, &buffer);
 342         if (!ACPI_SUCCESS(status))
 343                 return status;
 344         obj = (union acpi_object *)buffer.pointer;
 345         if (!obj || (obj->type != ACPI_TYPE_PACKAGE)) {
 346                 printk(KERN_ERR PREFIX "Invalid _BCL data\n");
 347                 status = -EFAULT;
 348                 goto err;
 349         }
 350
 351         *levels = obj;
 352
 353         return 0;
 354
 355 err:
 356         kfree(buffer.pointer);
 357
 358         return status;
 359 }
 360
 361 static int
 362 acpi_video_device_lcd_set_level(struct acpi_video_device *device, int level)
 363 {
 364         int status;
 365         int state;
 366
 367         status = acpi_execute_simple_method(device->dev->handle,
 368                                             "_BCM", level);
 369         if (ACPI_FAILURE(status)) {
 370                 ACPI_ERROR((AE_INFO, "Evaluating _BCM failed"));
 371                 return -EIO;
 372         }
 373
 374         device->brightness->curr = level;
 375         for (state = ACPI_VIDEO_FIRST_LEVEL; state < device->brightness->count;
 376              state++)
 377                 if (level == device->brightness->levels[state]) {
 378                         if (device->backlight)
 379                                 device->backlight->props.brightness =
 380                                         state - ACPI_VIDEO_FIRST_LEVEL;
 381                         return 0;
 382                 }
 383
 384         ACPI_ERROR((AE_INFO, "Current brightness invalid"));
 385         return -EINVAL;
 386 }
 387
 388 /*
 389  * For some buggy _BQC methods, we need to add a constant value to
 390  * the _BQC return value to get the actual current brightness level
 391  */
 392
 393 static int bqc_offset_aml_bug_workaround;
 394 static int video_set_bqc_offset(const struct dmi_system_id *d)
 395 {
 396         bqc_offset_aml_bug_workaround = 9;
 397         return 0;
 398 }
 399
 400 static int video_disable_backlight_sysfs_if(
 401         const struct dmi_system_id *d)
 402 {
 403         if (disable_backlight_sysfs_if == -1)
 404                 disable_backlight_sysfs_if = 1;
 405         return 0;
 406 }
 407
 408 static int video_set_device_id_scheme(const struct dmi_system_id *d)
 409 {
 410         device_id_scheme = true;
 411         return 0;
 412 }
 413
 414 static int video_enable_only_lcd(const struct dmi_system_id *d)
 415 {
 416         only_lcd = true;
 417         return 0;
 418 }
 419
 420 static int video_set_report_key_events(const struct dmi_system_id *id)
 421 {
 422         if (report_key_events == -1)
 423                 report_key_events = (uintptr_t)id->driver_data;
 424         return 0;
 425 }
 426
 427 static int video_hw_changes_brightness(
 428         const struct dmi_system_id *d)
 429 {
 430         if (hw_changes_brightness == -1)
 431                 hw_changes_brightness = 1;
 432         return 0;
 433 }
 434
 435 static const struct dmi_system_id video_dmi_table[] = {
 436         /*
 437          * Broken _BQC workaround http://bugzilla.kernel.org/show_bug.cgi?id=13121
 438          */
 439         {
 440          .callback = video_set_bqc_offset,
 441          .ident = "Acer Aspire 5720",
 442          .matches = {
 443                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
 444                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5720"),
 445                 },
 446         },
 447         {
 448          .callback = video_set_bqc_offset,
 449          .ident = "Acer Aspire 5710Z",
 450          .matches = {
 451                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
 452                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5710Z"),
 453                 },
 454         },
 455         {
 456          .callback = video_set_bqc_offset,
 457          .ident = "eMachines E510",
 458          .matches = {
 459                 DMI_MATCH(DMI_BOARD_VENDOR, "EMACHINES"),
 460                 DMI_MATCH(DMI_PRODUCT_NAME, "eMachines E510"),
 461                 },
 462         },
 463         {
 464          .callback = video_set_bqc_offset,
 465          .ident = "Acer Aspire 5315",
 466          .matches = {
 467                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
 468                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5315"),
 469                 },
 470         },
 471         {
 472          .callback = video_set_bqc_offset,
 473          .ident = "Acer Aspire 7720",
 474          .matches = {
 475                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
 476                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 7720"),
 477                 },
 478         },
 479
 480         /*
 481          * Some machines have a broken acpi-video interface for brightness
 482          * control, but still need an acpi_video_device_lcd_set_level() call
 483          * on resume to turn the backlight power on.  We Enable backlight
 484          * control on these systems, but do not register a backlight sysfs
 485          * as brightness control does not work.
 486          */
 487         {
 488          /* https://bugzilla.kernel.org/show_bug.cgi?id=21012 */
 489          .callback = video_disable_backlight_sysfs_if,
 490          .ident = "Toshiba Portege R700",
 491          .matches = {
 492                 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
 493                 DMI_MATCH(DMI_PRODUCT_NAME, "PORTEGE R700"),
 494                 },
 495         },
 496         {
 497          /* https://bugs.freedesktop.org/show_bug.cgi?id=82634 */
 498          .callback = video_disable_backlight_sysfs_if,
 499          .ident = "Toshiba Portege R830",
 500          .matches = {
 501                 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
 502                 DMI_MATCH(DMI_PRODUCT_NAME, "PORTEGE R830"),
 503                 },
 504         },
 505         {
 506          /* https://bugzilla.kernel.org/show_bug.cgi?id=21012 */
 507          .callback = video_disable_backlight_sysfs_if,
 508          .ident = "Toshiba Satellite R830",
 509          .matches = {
 510                 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
 511                 DMI_MATCH(DMI_PRODUCT_NAME, "SATELLITE R830"),
 512                 },
 513         },
 514         /*
 515          * 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_array(obj->package.count + ACPI_VIDEO_FIRST_LEVEL,
 874                                    sizeof(*br->levels),
 875                                    GFP_KERNEL);
 876         if (!br->levels) {
 877                 result = -ENOMEM;
 878                 goto out_free;
 879         }
 880
 881         for (i = 0; i < obj->package.count; i++) {
 882                 o = (union acpi_object *)&obj->package.elements[i];
 883                 if (o->type != ACPI_TYPE_INTEGER) {
 884                         printk(KERN_ERR PREFIX "Invalid data\n");
 885                         continue;
 886                 }
 887                 value = (u32) o->integer.value;
 888                 /* Skip duplicate entries */
 889                 if (count > ACPI_VIDEO_FIRST_LEVEL
 890                     && br->levels[count - 1] == value)
 891                         continue;
 892
 893                 br->levels[count] = value;
 894
 895                 if (br->levels[count] > max_level)
 896                         max_level = br->levels[count];
 897                 count++;
 898         }
 899
 900         /*
 901          * some buggy BIOS don't export the levels
 902          * when machine is on AC/Battery in _BCL package.
 903          * In this case, the first two elements in _BCL packages
 904          * are also supported brightness levels that OS should take care of.
 905          */
 906         for (i = ACPI_VIDEO_FIRST_LEVEL; i < count; i++) {
 907                 if (br->levels[i] == br->levels[ACPI_VIDEO_AC_LEVEL])
 908                         level_ac_battery++;
 909                 if (br->levels[i] == br->levels[ACPI_VIDEO_BATTERY_LEVEL])
 910                         level_ac_battery++;
 911         }
 912
 913         if (level_ac_battery < ACPI_VIDEO_FIRST_LEVEL) {
 914                 level_ac_battery = ACPI_VIDEO_FIRST_LEVEL - level_ac_battery;
 915                 br->flags._BCL_no_ac_battery_levels = 1;
 916                 for (i = (count - 1 + level_ac_battery);
 917                      i >= ACPI_VIDEO_FIRST_LEVEL; i--)
 918                         br->levels[i] = br->levels[i - level_ac_battery];
 919                 count += level_ac_battery;
 920         } else if (level_ac_battery > ACPI_VIDEO_FIRST_LEVEL)
 921                 ACPI_ERROR((AE_INFO, "Too many duplicates in _BCL package"));
 922
 923         /* Check if the _BCL package is in a reversed order */
 924         if (max_level == br->levels[ACPI_VIDEO_FIRST_LEVEL]) {
 925                 br->flags._BCL_reversed = 1;
 926                 sort(&br->levels[ACPI_VIDEO_FIRST_LEVEL],
 927                      count - ACPI_VIDEO_FIRST_LEVEL,
 928                      sizeof(br->levels[ACPI_VIDEO_FIRST_LEVEL]),
 929                      acpi_video_cmp_level, NULL);
 930         } else if (max_level != br->levels[count - 1])
 931                 ACPI_ERROR((AE_INFO,
 932                             "Found unordered _BCL package"));
 933
 934         br->count = count;
 935         *dev_br = br;
 936         if (pmax_level)
 937                 *pmax_level = max_level;
 938
 939 out:
 940         kfree(obj);
 941         return result;
 942 out_free:
 943         kfree(br);
 944         goto out;
 945 }
 946 EXPORT_SYMBOL(acpi_video_get_levels);
 947
 948 /*
 949  *  Arg:
 950  *      device  : video output device (LCD, CRT, ..)
 951  *
 952  *  Return Value:
 953  *      Maximum brightness level
 954  *
 955  *  Allocate and initialize device->brightness.
 956  */
 957
 958 static int
 959 acpi_video_init_brightness(struct acpi_video_device *device)
 960 {
 961         int i, max_level = 0;
 962         unsigned long long level, level_old;
 963         struct acpi_video_device_brightness *br = NULL;
 964         int result = -EINVAL;
 965
 966         result = acpi_video_get_levels(device->dev, &br, &max_level);
 967         if (result)
 968                 return result;
 969         device->brightness = br;
 970
 971         /* _BQC uses INDEX while _BCL uses VALUE in some laptops */
 972         br->curr = level = max_level;
 973
 974         if (!device->cap._BQC)
 975                 goto set_level;
 976
 977         result = acpi_video_device_lcd_get_level_current(device,
 978                                                          &level_old, true);
 979         if (result)
 980                 goto out_free_levels;
 981
 982         result = acpi_video_bqc_quirk(device, max_level, level_old);
 983         if (result)
 984                 goto out_free_levels;
 985         /*
 986          * cap._BQC may get cleared due to _BQC is found to be broken
 987          * in acpi_video_bqc_quirk, so check again here.
 988          */
 989         if (!device->cap._BQC)
 990                 goto set_level;
 991
 992         level = acpi_video_bqc_value_to_level(device, level_old);
 993         /*
 994          * On some buggy laptops, _BQC returns an uninitialized
 995          * value when invoked for the first time, i.e.
 996          * level_old is invalid (no matter whether it's a level
 997          * or an index). Set the backlight to max_level in this case.
 998          */
 999         for (i = ACPI_VIDEO_FIRST_LEVEL; i < br->count; i++)
1000                 if (level == br->levels[i])
1001                         break;
1002         if (i == br->count || !level)
1003                 level = max_level;
1004
1005 set_level:
1006         result = acpi_video_device_lcd_set_level(device, level);
1007         if (result)
1008                 goto out_free_levels;
1009
1010         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1011                           "found %d brightness levels\n",
1012                           br->count - ACPI_VIDEO_FIRST_LEVEL));
1013         return 0;
1014
1015 out_free_levels:
1016         kfree(br->levels);
1017         kfree(br);
1018         device->brightness = NULL;
1019         return result;
1020 }
1021
1022 /*
1023  *  Arg:
1024  *      device  : video output device (LCD, CRT, ..)
1025  *
1026  *  Return Value:
1027  *      None
1028  *
1029  *  Find out all required AML methods defined under the output
1030  *  device.
1031  */
1032
1033 static void acpi_video_device_find_cap(struct acpi_video_device *device)
1034 {
1035         if (acpi_has_method(device->dev->handle, "_ADR"))
1036                 device->cap._ADR = 1;
1037         if (acpi_has_method(device->dev->handle, "_BCL"))
1038                 device->cap._BCL = 1;
1039         if (acpi_has_method(device->dev->handle, "_BCM"))
1040                 device->cap._BCM = 1;
1041         if (acpi_has_method(device->dev->handle, "_BQC")) {
1042                 device->cap._BQC = 1;
1043         } else if (acpi_has_method(device->dev->handle, "_BCQ")) {
1044                 printk(KERN_WARNING FW_BUG "_BCQ is used instead of _BQC\n");
1045                 device->cap._BCQ = 1;
1046         }
1047
1048         if (acpi_has_method(device->dev->handle, "_DDC"))
1049                 device->cap._DDC = 1;
1050 }
1051
1052 /*
1053  *  Arg:
1054  *      device  : video output device (VGA)
1055  *
1056  *  Return Value:
1057  *      None
1058  *
1059  *  Find out all required AML methods defined under the video bus device.
1060  */
1061
1062 static void acpi_video_bus_find_cap(struct acpi_video_bus *video)
1063 {
1064         if (acpi_has_method(video->device->handle, "_DOS"))
1065                 video->cap._DOS = 1;
1066         if (acpi_has_method(video->device->handle, "_DOD"))
1067                 video->cap._DOD = 1;
1068         if (acpi_has_method(video->device->handle, "_ROM"))
1069                 video->cap._ROM = 1;
1070         if (acpi_has_method(video->device->handle, "_GPD"))
1071                 video->cap._GPD = 1;
1072         if (acpi_has_method(video->device->handle, "_SPD"))
1073                 video->cap._SPD = 1;
1074         if (acpi_has_method(video->device->handle, "_VPO"))
1075                 video->cap._VPO = 1;
1076 }
1077
1078 /*
1079  * Check whether the video bus device has required AML method to
1080  * support the desired features
1081  */
1082
1083 static int acpi_video_bus_check(struct acpi_video_bus *video)
1084 {
1085         acpi_status status = -ENOENT;
1086         struct pci_dev *dev;
1087
1088         if (!video)
1089                 return -EINVAL;
1090
1091         dev = acpi_get_pci_dev(video->device->handle);
1092         if (!dev)
1093                 return -ENODEV;
1094         pci_dev_put(dev);
1095
1096         /*
1097          * Since there is no HID, CID and so on for VGA driver, we have
1098          * to check well known required nodes.
1099          */
1100
1101         /* Does this device support video switching? */
1102         if (video->cap._DOS || video->cap._DOD) {
1103                 if (!video->cap._DOS) {
1104                         printk(KERN_WARNING FW_BUG
1105                                 "ACPI(%s) defines _DOD but not _DOS\n",
1106                                 acpi_device_bid(video->device));
1107                 }
1108                 video->flags.multihead = 1;
1109                 status = 0;
1110         }
1111
1112         /* Does this device support retrieving a video ROM? */
1113         if (video->cap._ROM) {
1114                 video->flags.rom = 1;
1115                 status = 0;
1116         }
1117
1118         /* Does this device support configuring which video device to POST? */
1119         if (video->cap._GPD && video->cap._SPD && video->cap._VPO) {
1120                 video->flags.post = 1;
1121                 status = 0;
1122         }
1123
1124         return status;
1125 }
1126
1127 /*
1128  * --------------------------------------------------------------------------
1129  *                               Driver Interface
1130  * --------------------------------------------------------------------------
1131  */
1132
1133 /* device interface */
1134 static struct acpi_video_device_attrib *
1135 acpi_video_get_device_attr(struct acpi_video_bus *video, unsigned long device_id)
1136 {
1137         struct acpi_video_enumerated_device *ids;
1138         int i;
1139
1140         for (i = 0; i < video->attached_count; i++) {
1141                 ids = &video->attached_array[i];
1142                 if ((ids->value.int_val & 0xffff) == device_id)
1143                         return &ids->value.attrib;
1144         }
1145
1146         return NULL;
1147 }
1148
1149 static int
1150 acpi_video_get_device_type(struct acpi_video_bus *video,
1151                            unsigned long device_id)
1152 {
1153         struct acpi_video_enumerated_device *ids;
1154         int i;
1155
1156         for (i = 0; i < video->attached_count; i++) {
1157                 ids = &video->attached_array[i];
1158                 if ((ids->value.int_val & 0xffff) == device_id)
1159                         return ids->value.int_val;
1160         }
1161
1162         return 0;
1163 }
1164
1165 static int
1166 acpi_video_bus_get_one_device(struct acpi_device *device,
1167                               struct acpi_video_bus *video)
1168 {
1169         unsigned long long device_id;
1170         int status, device_type;
1171         struct acpi_video_device *data;
1172         struct acpi_video_device_attrib *attribute;
1173
1174         status =
1175             acpi_evaluate_integer(device->handle, "_ADR", NULL, &device_id);
1176         /* Some device omits _ADR, we skip them instead of fail */
1177         if (ACPI_FAILURE(status))
1178                 return 0;
1179
1180         data = kzalloc(sizeof(struct acpi_video_device), GFP_KERNEL);
1181         if (!data)
1182                 return -ENOMEM;
1183
1184         strcpy(acpi_device_name(device), ACPI_VIDEO_DEVICE_NAME);
1185         strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
1186         device->driver_data = data;
1187
1188         data->device_id = device_id;
1189         data->video = video;
1190         data->dev = device;
1191         INIT_DELAYED_WORK(&data->switch_brightness_work,
1192                           acpi_video_switch_brightness);
1193
1194         attribute = acpi_video_get_device_attr(video, device_id);
1195
1196         if (attribute && (attribute->device_id_scheme || device_id_scheme)) {
1197                 switch (attribute->display_type) {
1198                 case ACPI_VIDEO_DISPLAY_CRT:
1199                         data->flags.crt = 1;
1200                         break;
1201                 case ACPI_VIDEO_DISPLAY_TV:
1202                         data->flags.tvout = 1;
1203                         break;
1204                 case ACPI_VIDEO_DISPLAY_DVI:
1205                         data->flags.dvi = 1;
1206                         break;
1207                 case ACPI_VIDEO_DISPLAY_LCD:
1208                         data->flags.lcd = 1;
1209                         break;
1210                 default:
1211                         data->flags.unknown = 1;
1212                         break;
1213                 }
1214                 if (attribute->bios_can_detect)
1215                         data->flags.bios = 1;
1216         } else {
1217                 /* Check for legacy IDs */
1218                 device_type = acpi_video_get_device_type(video, device_id);
1219                 /* Ignore bits 16 and 18-20 */
1220                 switch (device_type & 0xffe2ffff) {
1221                 case ACPI_VIDEO_DISPLAY_LEGACY_MONITOR:
1222                         data->flags.crt = 1;
1223                         break;
1224                 case ACPI_VIDEO_DISPLAY_LEGACY_PANEL:
1225                         data->flags.lcd = 1;
1226                         break;
1227                 case ACPI_VIDEO_DISPLAY_LEGACY_TV:
1228                         data->flags.tvout = 1;
1229                         break;
1230                 default:
1231                         data->flags.unknown = 1;
1232                 }
1233         }
1234
1235         acpi_video_device_bind(video, data);
1236         acpi_video_device_find_cap(data);
1237
1238         mutex_lock(&video->device_list_lock);
1239         list_add_tail(&data->entry, &video->video_device_list);
1240         mutex_unlock(&video->device_list_lock);
1241
1242         return status;
1243 }
1244
1245 /*
1246  *  Arg:
1247  *      video   : video bus device
1248  *
1249  *  Return:
1250  *      none
1251  *
1252  *  Enumerate the video device list of the video bus,
1253  *  bind the ids with the corresponding video devices
1254  *  under the video bus.
1255  */
1256
1257 static void acpi_video_device_rebind(struct acpi_video_bus *video)
1258 {
1259         struct acpi_video_device *dev;
1260
1261         mutex_lock(&video->device_list_lock);
1262
1263         list_for_each_entry(dev, &video->video_device_list, entry)
1264                 acpi_video_device_bind(video, dev);
1265
1266         mutex_unlock(&video->device_list_lock);
1267 }
1268
1269 /*
1270  *  Arg:
1271  *      video   : video bus device
1272  *      device  : video output device under the video
1273  *              bus
1274  *
1275  *  Return:
1276  *      none
1277  *
1278  *  Bind the ids with the corresponding video devices
1279  *  under the video bus.
1280  */
1281
1282 static void
1283 acpi_video_device_bind(struct acpi_video_bus *video,
1284                        struct acpi_video_device *device)
1285 {
1286         struct acpi_video_enumerated_device *ids;
1287         int i;
1288
1289         for (i = 0; i < video->attached_count; i++) {
1290                 ids = &video->attached_array[i];
1291                 if (device->device_id == (ids->value.int_val & 0xffff)) {
1292                         ids->bind_info = device;
1293                         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "device_bind %d\n", i));
1294                 }
1295         }
1296 }
1297
1298 static bool acpi_video_device_in_dod(struct acpi_video_device *device)
1299 {
1300         struct acpi_video_bus *video = device->video;
1301         int i;
1302
1303         /*
1304          * If we have a broken _DOD or we have more than 8 output devices
1305          * under the graphics controller node that we can't proper deal with
1306          * in the operation region code currently, no need to test.
1307          */
1308         if (!video->attached_count || video->child_count > 8)
1309                 return true;
1310
1311         for (i = 0; i < video->attached_count; i++) {
1312                 if ((video->attached_array[i].value.int_val & 0xfff) ==
1313                     (device->device_id & 0xfff))
1314                         return true;
1315         }
1316
1317         return false;
1318 }
1319
1320 /*
1321  *  Arg:
1322  *      video   : video bus device
1323  *
1324  *  Return:
1325  *      < 0     : error
1326  *
1327  *  Call _DOD to enumerate all devices attached to display adapter
1328  *
1329  */
1330
1331 static int acpi_video_device_enumerate(struct acpi_video_bus *video)
1332 {
1333         int status;
1334         int count;
1335         int i;
1336         struct acpi_video_enumerated_device *active_list;
1337         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1338         union acpi_object *dod = NULL;
1339         union acpi_object *obj;
1340
1341         if (!video->cap._DOD)
1342                 return AE_NOT_EXIST;
1343
1344         status = acpi_evaluate_object(video->device->handle, "_DOD", NULL, &buffer);
1345         if (!ACPI_SUCCESS(status)) {
1346                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _DOD"));
1347                 return status;
1348         }
1349
1350         dod = buffer.pointer;
1351         if (!dod || (dod->type != ACPI_TYPE_PACKAGE)) {
1352                 ACPI_EXCEPTION((AE_INFO, status, "Invalid _DOD data"));
1353                 status = -EFAULT;
1354                 goto out;
1355         }
1356
1357         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d video heads in _DOD\n",
1358                           dod->package.count));
1359
1360         active_list = kcalloc(1 + dod->package.count,
1361                               sizeof(struct acpi_video_enumerated_device),
1362                               GFP_KERNEL);
1363         if (!active_list) {
1364                 status = -ENOMEM;
1365                 goto out;
1366         }
1367
1368         count = 0;
1369         for (i = 0; i < dod->package.count; i++) {
1370                 obj = &dod->package.elements[i];
1371
1372                 if (obj->type != ACPI_TYPE_INTEGER) {
1373                         printk(KERN_ERR PREFIX
1374                                 "Invalid _DOD data in element %d\n", i);
1375                         continue;
1376                 }
1377
1378                 active_list[count].value.int_val = obj->integer.value;
1379                 active_list[count].bind_info = NULL;
1380                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "dod element[%d] = %d\n", i,
1381                                   (int)obj->integer.value));
1382                 count++;
1383         }
1384
1385         kfree(video->attached_array);
1386
1387         video->attached_array = active_list;
1388         video->attached_count = count;
1389
1390 out:
1391         kfree(buffer.pointer);
1392         return status;
1393 }
1394
1395 static int
1396 acpi_video_get_next_level(struct acpi_video_device *device,
1397                           u32 level_current, u32 event)
1398 {
1399         int min, max, min_above, max_below, i, l, delta = 255;
1400         max = max_below = 0;
1401         min = min_above = 255;
1402         /* Find closest level to level_current */
1403         for (i = ACPI_VIDEO_FIRST_LEVEL; i < device->brightness->count; i++) {
1404                 l = device->brightness->levels[i];
1405                 if (abs(l - level_current) < abs(delta)) {
1406                         delta = l - level_current;
1407                         if (!delta)
1408                                 break;
1409                 }
1410         }
1411         /* Ajust level_current to closest available level */
1412         level_current += delta;
1413         for (i = ACPI_VIDEO_FIRST_LEVEL; i < device->brightness->count; i++) {
1414                 l = device->brightness->levels[i];
1415                 if (l < min)
1416                         min = l;
1417                 if (l > max)
1418                         max = l;
1419                 if (l < min_above && l > level_current)
1420                         min_above = l;
1421                 if (l > max_below && l < level_current)
1422                         max_below = l;
1423         }
1424
1425         switch (event) {
1426         case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:
1427                 return (level_current < max) ? min_above : min;
1428         case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:
1429                 return (level_current < max) ? min_above : max;
1430         case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:
1431                 return (level_current > min) ? max_below : min;
1432         case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS:
1433         case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:
1434                 return 0;
1435         default:
1436                 return level_current;
1437         }
1438 }
1439
1440 static void
1441 acpi_video_switch_brightness(struct work_struct *work)
1442 {
1443         struct acpi_video_device *device = container_of(to_delayed_work(work),
1444                              struct acpi_video_device, switch_brightness_work);
1445         unsigned long long level_current, level_next;
1446         int event = device->switch_brightness_event;
1447         int result = -EINVAL;
1448
1449         /* no warning message if acpi_backlight=vendor or a quirk is used */
1450         if (!device->backlight)
1451                 return;
1452
1453         if (!device->brightness)
1454                 goto out;
1455
1456         result = acpi_video_device_lcd_get_level_current(device,
1457                                                          &level_current,
1458                                                          false);
1459         if (result)
1460                 goto out;
1461
1462         level_next = acpi_video_get_next_level(device, level_current, event);
1463
1464         result = acpi_video_device_lcd_set_level(device, level_next);
1465
1466         if (!result)
1467                 backlight_force_update(device->backlight,
1468                                        BACKLIGHT_UPDATE_HOTKEY);
1469
1470 out:
1471         if (result)
1472                 printk(KERN_ERR PREFIX "Failed to switch the brightness\n");
1473 }
1474
1475 int acpi_video_get_edid(struct acpi_device *device, int type, int device_id,
1476                         void **edid)
1477 {
1478         struct acpi_video_bus *video;
1479         struct acpi_video_device *video_device;
1480         union acpi_object *buffer = NULL;
1481         acpi_status status;
1482         int i, length;
1483
1484         if (!device || !acpi_driver_data(device))
1485                 return -EINVAL;
1486
1487         video = acpi_driver_data(device);
1488
1489         for (i = 0; i < video->attached_count; i++) {
1490                 video_device = video->attached_array[i].bind_info;
1491                 length = 256;
1492
1493                 if (!video_device)
1494                         continue;
1495
1496                 if (!video_device->cap._DDC)
1497                         continue;
1498
1499                 if (type) {
1500                         switch (type) {
1501                         case ACPI_VIDEO_DISPLAY_CRT:
1502                                 if (!video_device->flags.crt)
1503                                         continue;
1504                                 break;
1505                         case ACPI_VIDEO_DISPLAY_TV:
1506                                 if (!video_device->flags.tvout)
1507                                         continue;
1508                                 break;
1509                         case ACPI_VIDEO_DISPLAY_DVI:
1510                                 if (!video_device->flags.dvi)
1511                                         continue;
1512                                 break;
1513                         case ACPI_VIDEO_DISPLAY_LCD:
1514                                 if (!video_device->flags.lcd)
1515                                         continue;
1516                                 break;
1517                         }
1518                 } else if (video_device->device_id != device_id) {
1519                         continue;
1520                 }
1521
1522                 status = acpi_video_device_EDID(video_device, &buffer, length);
1523
1524                 if (ACPI_FAILURE(status) || !buffer ||
1525                     buffer->type != ACPI_TYPE_BUFFER) {
1526                         length = 128;
1527                         status = acpi_video_device_EDID(video_device, &buffer,
1528                                                         length);
1529                         if (ACPI_FAILURE(status) || !buffer ||
1530                             buffer->type != ACPI_TYPE_BUFFER) {
1531                                 continue;
1532                         }
1533                 }
1534
1535                 *edid = buffer->buffer.pointer;
1536                 return length;
1537         }
1538
1539         return -ENODEV;
1540 }
1541 EXPORT_SYMBOL(acpi_video_get_edid);
1542
1543 static int
1544 acpi_video_bus_get_devices(struct acpi_video_bus *video,
1545                            struct acpi_device *device)
1546 {
1547         int status = 0;
1548         struct acpi_device *dev;
1549
1550         /*
1551          * There are systems where video module known to work fine regardless
1552          * of broken _DOD and ignoring returned value here doesn't cause
1553          * any issues later.
1554          */
1555         acpi_video_device_enumerate(video);
1556
1557         list_for_each_entry(dev, &device->children, node) {
1558
1559                 status = acpi_video_bus_get_one_device(dev, video);
1560                 if (status) {
1561                         dev_err(&dev->dev, "Can't attach device\n");
1562                         break;
1563                 }
1564                 video->child_count++;
1565         }
1566         return status;
1567 }
1568
1569 /* acpi_video interface */
1570
1571 /*
1572  * Win8 requires setting bit2 of _DOS to let firmware know it shouldn't
1573  * preform any automatic brightness change on receiving a notification.
1574  */
1575 static int acpi_video_bus_start_devices(struct acpi_video_bus *video)
1576 {
1577         return acpi_video_bus_DOS(video, 0,
1578                                   acpi_osi_is_win8() ? 1 : 0);
1579 }
1580
1581 static int acpi_video_bus_stop_devices(struct acpi_video_bus *video)
1582 {
1583         return acpi_video_bus_DOS(video, 0,
1584                                   acpi_osi_is_win8() ? 0 : 1);
1585 }
1586
1587 static void acpi_video_bus_notify(struct acpi_device *device, u32 event)
1588 {
1589         struct acpi_video_bus *video = acpi_driver_data(device);
1590         struct input_dev *input;
1591         int keycode = 0;
1592
1593         if (!video || !video->input)
1594                 return;
1595
1596         input = video->input;
1597
1598         switch (event) {
1599         case ACPI_VIDEO_NOTIFY_SWITCH:  /* User requested a switch,
1600                                          * most likely via hotkey. */
1601                 keycode = KEY_SWITCHVIDEOMODE;
1602                 break;
1603
1604         case ACPI_VIDEO_NOTIFY_PROBE:   /* User plugged in or removed a video
1605                                          * connector. */
1606                 acpi_video_device_enumerate(video);
1607                 acpi_video_device_rebind(video);
1608                 keycode = KEY_SWITCHVIDEOMODE;
1609                 break;
1610
1611         case ACPI_VIDEO_NOTIFY_CYCLE:   /* Cycle Display output hotkey pressed. */
1612                 keycode = KEY_SWITCHVIDEOMODE;
1613                 break;
1614         case ACPI_VIDEO_NOTIFY_NEXT_OUTPUT:     /* Next Display output hotkey pressed. */
1615                 keycode = KEY_VIDEO_NEXT;
1616                 break;
1617         case ACPI_VIDEO_NOTIFY_PREV_OUTPUT:     /* previous Display output hotkey pressed. */
1618                 keycode = KEY_VIDEO_PREV;
1619                 break;
1620
1621         default:
1622                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1623                                   "Unsupported event [0x%x]\n", event));
1624                 break;
1625         }
1626
1627         if (acpi_notifier_call_chain(device, event, 0))
1628                 /* Something vetoed the keypress. */
1629                 keycode = 0;
1630
1631         if (keycode && (report_key_events & REPORT_OUTPUT_KEY_EVENTS)) {
1632                 input_report_key(input, keycode, 1);
1633                 input_sync(input);
1634                 input_report_key(input, keycode, 0);
1635                 input_sync(input);
1636         }
1637
1638         return;
1639 }
1640
1641 static void brightness_switch_event(struct acpi_video_device *video_device,
1642                                     u32 event)
1643 {
1644         if (!brightness_switch_enabled)
1645                 return;
1646
1647         video_device->switch_brightness_event = event;
1648         schedule_delayed_work(&video_device->switch_brightness_work, HZ / 10);
1649 }
1650
1651 static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data)
1652 {
1653         struct acpi_video_device *video_device = data;
1654         struct acpi_device *device = NULL;
1655         struct acpi_video_bus *bus;
1656         struct input_dev *input;
1657         int keycode = 0;
1658
1659         if (!video_device)
1660                 return;
1661
1662         device = video_device->dev;
1663         bus = video_device->video;
1664         input = bus->input;
1665
1666         if (hw_changes_brightness > 0) {
1667                 if (video_device->backlight)
1668                         backlight_force_update(video_device->backlight,
1669                                                BACKLIGHT_UPDATE_HOTKEY);
1670                 acpi_notifier_call_chain(device, event, 0);
1671                 return;
1672         }
1673
1674         switch (event) {
1675         case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:        /* Cycle brightness */
1676                 brightness_switch_event(video_device, event);
1677                 keycode = KEY_BRIGHTNESS_CYCLE;
1678                 break;
1679         case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:  /* Increase brightness */
1680                 brightness_switch_event(video_device, event);
1681                 keycode = KEY_BRIGHTNESSUP;
1682                 break;
1683         case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:  /* Decrease brightness */
1684                 brightness_switch_event(video_device, event);
1685                 keycode = KEY_BRIGHTNESSDOWN;
1686                 break;
1687         case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS: /* zero brightness */
1688                 brightness_switch_event(video_device, event);
1689                 keycode = KEY_BRIGHTNESS_ZERO;
1690                 break;
1691         case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:     /* display device off */
1692                 brightness_switch_event(video_device, event);
1693                 keycode = KEY_DISPLAY_OFF;
1694                 break;
1695         default:
1696                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1697                                   "Unsupported event [0x%x]\n", event));
1698                 break;
1699         }
1700
1701         acpi_notifier_call_chain(device, event, 0);
1702
1703         if (keycode && (report_key_events & REPORT_BRIGHTNESS_KEY_EVENTS)) {
1704                 input_report_key(input, keycode, 1);
1705                 input_sync(input);
1706                 input_report_key(input, keycode, 0);
1707                 input_sync(input);
1708         }
1709
1710         return;
1711 }
1712
1713 static int acpi_video_resume(struct notifier_block *nb,
1714                                 unsigned long val, void *ign)
1715 {
1716         struct acpi_video_bus *video;
1717         struct acpi_video_device *video_device;
1718         int i;
1719
1720         switch (val) {
1721         case PM_HIBERNATION_PREPARE:
1722         case PM_SUSPEND_PREPARE:
1723         case PM_RESTORE_PREPARE:
1724                 return NOTIFY_DONE;
1725         }
1726
1727         video = container_of(nb, struct acpi_video_bus, pm_nb);
1728
1729         dev_info(&video->device->dev, "Restoring backlight state\n");
1730
1731         for (i = 0; i < video->attached_count; i++) {
1732                 video_device = video->attached_array[i].bind_info;
1733                 if (video_device && video_device->brightness)
1734                         acpi_video_device_lcd_set_level(video_device,
1735                                         video_device->brightness->curr);
1736         }
1737
1738         return NOTIFY_OK;
1739 }
1740
1741 static acpi_status
1742 acpi_video_bus_match(acpi_handle handle, u32 level, void *context,
1743                         void **return_value)
1744 {
1745         struct acpi_device *device = context;
1746         struct acpi_device *sibling;
1747         int result;
1748
1749         if (handle == device->handle)
1750                 return AE_CTRL_TERMINATE;
1751
1752         result = acpi_bus_get_device(handle, &sibling);
1753         if (result)
1754                 return AE_OK;
1755
1756         if (!strcmp(acpi_device_name(sibling), ACPI_VIDEO_BUS_NAME))
1757                         return AE_ALREADY_EXISTS;
1758
1759         return AE_OK;
1760 }
1761
1762 static void acpi_video_dev_register_backlight(struct acpi_video_device *device)
1763 {
1764         struct backlight_properties props;
1765         struct pci_dev *pdev;
1766         acpi_handle acpi_parent;
1767         struct device *parent = NULL;
1768         int result;
1769         static int count;
1770         char *name;
1771
1772         result = acpi_video_init_brightness(device);
1773         if (result)
1774                 return;
1775
1776         if (disable_backlight_sysfs_if > 0)
1777                 return;
1778
1779         name = kasprintf(GFP_KERNEL, "acpi_video%d", count);
1780         if (!name)
1781                 return;
1782         count++;
1783
1784         acpi_get_parent(device->dev->handle, &acpi_parent);
1785
1786         pdev = acpi_get_pci_dev(acpi_parent);
1787         if (pdev) {
1788                 parent = &pdev->dev;
1789                 pci_dev_put(pdev);
1790         }
1791
1792         memset(&props, 0, sizeof(struct backlight_properties));
1793         props.type = BACKLIGHT_FIRMWARE;
1794         props.max_brightness =
1795                 device->brightness->count - ACPI_VIDEO_FIRST_LEVEL - 1;
1796         device->backlight = backlight_device_register(name,
1797                                                       parent,
1798                                                       device,
1799                                                       &acpi_backlight_ops,
1800                                                       &props);
1801         kfree(name);
1802         if (IS_ERR(device->backlight)) {
1803                 device->backlight = NULL;
1804                 return;
1805         }
1806
1807         /*
1808          * Save current brightness level in case we have to restore it
1809          * before acpi_video_device_lcd_set_level() is called next time.
1810          */
1811         device->backlight->props.brightness =
1812                         acpi_video_get_brightness(device->backlight);
1813
1814         device->cooling_dev = thermal_cooling_device_register("LCD",
1815                                 device->dev, &video_cooling_ops);
1816         if (IS_ERR(device->cooling_dev)) {
1817                 /*
1818                  * Set cooling_dev to NULL so we don't crash trying to free it.
1819                  * Also, why the hell we are returning early and not attempt to
1820                  * register video output if cooling device registration failed?
1821                  * -- dtor
1822                  */
1823                 device->cooling_dev = NULL;
1824                 return;
1825         }
1826
1827         dev_info(&device->dev->dev, "registered as cooling_device%d\n",
1828                  device->cooling_dev->id);
1829         result = sysfs_create_link(&device->dev->dev.kobj,
1830                         &device->cooling_dev->device.kobj,
1831                         "thermal_cooling");
1832         if (result)
1833                 printk(KERN_ERR PREFIX "Create sysfs link\n");
1834         result = sysfs_create_link(&device->cooling_dev->device.kobj,
1835                         &device->dev->dev.kobj, "device");
1836         if (result)
1837                 printk(KERN_ERR PREFIX "Create sysfs link\n");
1838 }
1839
1840 static void acpi_video_run_bcl_for_osi(struct acpi_video_bus *video)
1841 {
1842         struct acpi_video_device *dev;
1843         union acpi_object *levels;
1844
1845         mutex_lock(&video->device_list_lock);
1846         list_for_each_entry(dev, &video->video_device_list, entry) {
1847                 if (!acpi_video_device_lcd_query_levels(dev->dev->handle, &levels))
1848                         kfree(levels);
1849         }
1850         mutex_unlock(&video->device_list_lock);
1851 }
1852
1853 static bool acpi_video_should_register_backlight(struct acpi_video_device *dev)
1854 {
1855         /*
1856          * Do not create backlight device for video output
1857          * device that is not in the enumerated list.
1858          */
1859         if (!acpi_video_device_in_dod(dev)) {
1860                 dev_dbg(&dev->dev->dev, "not in _DOD list, ignore\n");
1861                 return false;
1862         }
1863
1864         if (only_lcd)
1865                 return dev->flags.lcd;
1866         return true;
1867 }
1868
1869 static int acpi_video_bus_register_backlight(struct acpi_video_bus *video)
1870 {
1871         struct acpi_video_device *dev;
1872
1873         if (video->backlight_registered)
1874                 return 0;
1875
1876         acpi_video_run_bcl_for_osi(video);
1877
1878         if (acpi_video_get_backlight_type() != acpi_backlight_video)
1879                 return 0;
1880
1881         mutex_lock(&video->device_list_lock);
1882         list_for_each_entry(dev, &video->video_device_list, entry) {
1883                 if (acpi_video_should_register_backlight(dev))
1884                         acpi_video_dev_register_backlight(dev);
1885         }
1886         mutex_unlock(&video->device_list_lock);
1887
1888         video->backlight_registered = true;
1889
1890         video->pm_nb.notifier_call = acpi_video_resume;
1891         video->pm_nb.priority = 0;
1892         return register_pm_notifier(&video->pm_nb);
1893 }
1894
1895 static void acpi_video_dev_unregister_backlight(struct acpi_video_device *device)
1896 {
1897         if (device->backlight) {
1898                 backlight_device_unregister(device->backlight);
1899                 device->backlight = NULL;
1900         }
1901         if (device->brightness) {
1902                 kfree(device->brightness->levels);
1903                 kfree(device->brightness);
1904                 device->brightness = NULL;
1905         }
1906         if (device->cooling_dev) {
1907                 sysfs_remove_link(&device->dev->dev.kobj, "thermal_cooling");
1908                 sysfs_remove_link(&device->cooling_dev->device.kobj, "device");
1909                 thermal_cooling_device_unregister(device->cooling_dev);
1910                 device->cooling_dev = NULL;
1911         }
1912 }
1913
1914 static int acpi_video_bus_unregister_backlight(struct acpi_video_bus *video)
1915 {
1916         struct acpi_video_device *dev;
1917         int error;
1918
1919         if (!video->backlight_registered)
1920                 return 0;
1921
1922         error = unregister_pm_notifier(&video->pm_nb);
1923
1924         mutex_lock(&video->device_list_lock);
1925         list_for_each_entry(dev, &video->video_device_list, entry)
1926                 acpi_video_dev_unregister_backlight(dev);
1927         mutex_unlock(&video->device_list_lock);
1928
1929         video->backlight_registered = false;
1930
1931         return error;
1932 }
1933
1934 static void acpi_video_dev_add_notify_handler(struct acpi_video_device *device)
1935 {
1936         acpi_status status;
1937         struct acpi_device *adev = device->dev;
1938
1939         status = acpi_install_notify_handler(adev->handle, ACPI_DEVICE_NOTIFY,
1940                                              acpi_video_device_notify, device);
1941         if (ACPI_FAILURE(status))
1942                 dev_err(&adev->dev, "Error installing notify handler\n");
1943         else
1944                 device->flags.notify = 1;
1945 }
1946
1947 static int acpi_video_bus_add_notify_handler(struct acpi_video_bus *video)
1948 {
1949         struct input_dev *input;
1950         struct acpi_video_device *dev;
1951         int error;
1952
1953         video->input = input = input_allocate_device();
1954         if (!input) {
1955                 error = -ENOMEM;
1956                 goto out;
1957         }
1958
1959         error = acpi_video_bus_start_devices(video);
1960         if (error)
1961                 goto err_free_input;
1962
1963         snprintf(video->phys, sizeof(video->phys),
1964                         "%s/video/input0", acpi_device_hid(video->device));
1965
1966         input->name = acpi_device_name(video->device);
1967         input->phys = video->phys;
1968         input->id.bustype = BUS_HOST;
1969         input->id.product = 0x06;
1970         input->dev.parent = &video->device->dev;
1971         input->evbit[0] = BIT(EV_KEY);
1972         set_bit(KEY_SWITCHVIDEOMODE, input->keybit);
1973         set_bit(KEY_VIDEO_NEXT, input->keybit);
1974         set_bit(KEY_VIDEO_PREV, input->keybit);
1975         set_bit(KEY_BRIGHTNESS_CYCLE, input->keybit);
1976         set_bit(KEY_BRIGHTNESSUP, input->keybit);
1977         set_bit(KEY_BRIGHTNESSDOWN, input->keybit);
1978         set_bit(KEY_BRIGHTNESS_ZERO, input->keybit);
1979         set_bit(KEY_DISPLAY_OFF, input->keybit);
1980
1981         error = input_register_device(input);
1982         if (error)
1983                 goto err_stop_dev;
1984
1985         mutex_lock(&video->device_list_lock);
1986         list_for_each_entry(dev, &video->video_device_list, entry)
1987                 acpi_video_dev_add_notify_handler(dev);
1988         mutex_unlock(&video->device_list_lock);
1989
1990         return 0;
1991
1992 err_stop_dev:
1993         acpi_video_bus_stop_devices(video);
1994 err_free_input:
1995         input_free_device(input);
1996         video->input = NULL;
1997 out:
1998         return error;
1999 }
2000
2001 static void acpi_video_dev_remove_notify_handler(struct acpi_video_device *dev)
2002 {
2003         if (dev->flags.notify) {
2004                 acpi_remove_notify_handler(dev->dev->handle, ACPI_DEVICE_NOTIFY,
2005                                            acpi_video_device_notify);
2006                 dev->flags.notify = 0;
2007         }
2008 }
2009
2010 static void acpi_video_bus_remove_notify_handler(struct acpi_video_bus *video)
2011 {
2012         struct acpi_video_device *dev;
2013
2014         mutex_lock(&video->device_list_lock);
2015         list_for_each_entry(dev, &video->video_device_list, entry)
2016                 acpi_video_dev_remove_notify_handler(dev);
2017         mutex_unlock(&video->device_list_lock);
2018
2019         acpi_video_bus_stop_devices(video);
2020         input_unregister_device(video->input);
2021         video->input = NULL;
2022 }
2023
2024 static int acpi_video_bus_put_devices(struct acpi_video_bus *video)
2025 {
2026         struct acpi_video_device *dev, *next;
2027
2028         mutex_lock(&video->device_list_lock);
2029         list_for_each_entry_safe(dev, next, &video->video_device_list, entry) {
2030                 list_del(&dev->entry);
2031                 kfree(dev);
2032         }
2033         mutex_unlock(&video->device_list_lock);
2034
2035         return 0;
2036 }
2037
2038 static int instance;
2039
2040 static int acpi_video_bus_add(struct acpi_device *device)
2041 {
2042         struct acpi_video_bus *video;
2043         int error;
2044         acpi_status status;
2045
2046         status = acpi_walk_namespace(ACPI_TYPE_DEVICE,
2047                                 device->parent->handle, 1,
2048                                 acpi_video_bus_match, NULL,
2049                                 device, NULL);
2050         if (status == AE_ALREADY_EXISTS) {
2051                 printk(KERN_WARNING FW_BUG
2052                         "Duplicate ACPI video bus devices for the"
2053                         " same VGA controller, please try module "
2054                         "parameter \"video.allow_duplicates=1\""
2055                         "if the current driver doesn't work.\n");
2056                 if (!allow_duplicates)
2057                         return -ENODEV;
2058         }
2059
2060         video = kzalloc(sizeof(struct acpi_video_bus), GFP_KERNEL);
2061         if (!video)
2062                 return -ENOMEM;
2063
2064         /* a hack to fix the duplicate name "VID" problem on T61 */
2065         if (!strcmp(device->pnp.bus_id, "VID")) {
2066                 if (instance)
2067                         device->pnp.bus_id[3] = '0' + instance;
2068                 instance++;
2069         }
2070         /* a hack to fix the duplicate name "VGA" problem on Pa 3553 */
2071         if (!strcmp(device->pnp.bus_id, "VGA")) {
2072                 if (instance)
2073                         device->pnp.bus_id[3] = '0' + instance;
2074                 instance++;
2075         }
2076
2077         video->device = device;
2078         strcpy(acpi_device_name(device), ACPI_VIDEO_BUS_NAME);
2079         strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
2080         device->driver_data = video;
2081
2082         acpi_video_bus_find_cap(video);
2083         error = acpi_video_bus_check(video);
2084         if (error)
2085                 goto err_free_video;
2086
2087         mutex_init(&video->device_list_lock);
2088         INIT_LIST_HEAD(&video->video_device_list);
2089
2090         error = acpi_video_bus_get_devices(video, device);
2091         if (error)
2092                 goto err_put_video;
2093
2094         printk(KERN_INFO PREFIX "%s [%s] (multi-head: %s  rom: %s  post: %s)\n",
2095                ACPI_VIDEO_DEVICE_NAME, acpi_device_bid(device),
2096                video->flags.multihead ? "yes" : "no",
2097                video->flags.rom ? "yes" : "no",
2098                video->flags.post ? "yes" : "no");
2099         mutex_lock(&video_list_lock);
2100         list_add_tail(&video->entry, &video_bus_head);
2101         mutex_unlock(&video_list_lock);
2102
2103         acpi_video_bus_register_backlight(video);
2104         acpi_video_bus_add_notify_handler(video);
2105
2106         return 0;
2107
2108 err_put_video:
2109         acpi_video_bus_put_devices(video);
2110         kfree(video->attached_array);
2111 err_free_video:
2112         kfree(video);
2113         device->driver_data = NULL;
2114
2115         return error;
2116 }
2117
2118 static int acpi_video_bus_remove(struct acpi_device *device)
2119 {
2120         struct acpi_video_bus *video = NULL;
2121
2122
2123         if (!device || !acpi_driver_data(device))
2124                 return -EINVAL;
2125
2126         video = acpi_driver_data(device);
2127
2128         acpi_video_bus_remove_notify_handler(video);
2129         acpi_video_bus_unregister_backlight(video);
2130         acpi_video_bus_put_devices(video);
2131
2132         mutex_lock(&video_list_lock);
2133         list_del(&video->entry);
2134         mutex_unlock(&video_list_lock);
2135
2136         kfree(video->attached_array);
2137         kfree(video);
2138
2139         return 0;
2140 }
2141
2142 static int __init is_i740(struct pci_dev *dev)
2143 {
2144         if (dev->device == 0x00D1)
2145                 return 1;
2146         if (dev->device == 0x7000)
2147                 return 1;
2148         return 0;
2149 }
2150
2151 static int __init intel_opregion_present(void)
2152 {
2153         int opregion = 0;
2154         struct pci_dev *dev = NULL;
2155         u32 address;
2156
2157         for_each_pci_dev(dev) {
2158                 if ((dev->class >> 8) != PCI_CLASS_DISPLAY_VGA)
2159                         continue;
2160                 if (dev->vendor != PCI_VENDOR_ID_INTEL)
2161                         continue;
2162                 /* We don't want to poke around undefined i740 registers */
2163                 if (is_i740(dev))
2164                         continue;
2165                 pci_read_config_dword(dev, 0xfc, &address);
2166                 if (!address)
2167                         continue;
2168                 opregion = 1;
2169         }
2170         return opregion;
2171 }
2172
2173 /* Check if the chassis-type indicates there is no builtin LCD panel */
2174 static bool dmi_is_desktop(void)
2175 {
2176         const char *chassis_type;
2177         unsigned long type;
2178
2179         chassis_type = dmi_get_system_info(DMI_CHASSIS_TYPE);
2180         if (!chassis_type)
2181                 return false;
2182
2183         if (kstrtoul(chassis_type, 10, &type) != 0)
2184                 return false;
2185
2186         switch (type) {
2187         case 0x03: /* Desktop */
2188         case 0x04: /* Low Profile Desktop */
2189         case 0x05: /* Pizza Box */
2190         case 0x06: /* Mini Tower */
2191         case 0x07: /* Tower */
2192         case 0x10: /* Lunch Box */
2193         case 0x11: /* Main Server Chassis */
2194                 return true;
2195         }
2196
2197         return false;
2198 }
2199
2200 int acpi_video_register(void)
2201 {
2202         int ret = 0;
2203
2204         mutex_lock(&register_count_mutex);
2205         if (register_count) {
2206                 /*
2207                  * if the function of acpi_video_register is already called,
2208                  * don't register the acpi_vide_bus again and return no error.
2209                  */
2210                 goto leave;
2211         }
2212
2213         /*
2214          * We're seeing a lot of bogus backlight interfaces on newer machines
2215          * without a LCD such as desktops, servers and HDMI sticks. Checking
2216          * the lcd flag fixes this, so enable this on any machines which are
2217          * win8 ready (where we also prefer the native backlight driver, so
2218          * normally the acpi_video code should not register there anyways).
2219          */
2220         if (only_lcd == -1) {
2221                 if (dmi_is_desktop() && acpi_osi_is_win8())
2222                         only_lcd = true;
2223                 else
2224                         only_lcd = false;
2225         }
2226
2227         dmi_check_system(video_dmi_table);
2228
2229         ret = acpi_bus_register_driver(&acpi_video_bus);
2230         if (ret)
2231                 goto leave;
2232
2233         /*
2234          * When the acpi_video_bus is loaded successfully, increase
2235          * the counter reference.
2236          */
2237         register_count = 1;
2238
2239 leave:
2240         mutex_unlock(&register_count_mutex);
2241         return ret;
2242 }
2243 EXPORT_SYMBOL(acpi_video_register);
2244
2245 void acpi_video_unregister(void)
2246 {
2247         mutex_lock(&register_count_mutex);
2248         if (register_count) {
2249                 acpi_bus_unregister_driver(&acpi_video_bus);
2250                 register_count = 0;
2251         }
2252         mutex_unlock(&register_count_mutex);
2253 }
2254 EXPORT_SYMBOL(acpi_video_unregister);
2255
2256 void acpi_video_unregister_backlight(void)
2257 {
2258         struct acpi_video_bus *video;
2259
2260         mutex_lock(&register_count_mutex);
2261         if (register_count) {
2262                 mutex_lock(&video_list_lock);
2263                 list_for_each_entry(video, &video_bus_head, entry)
2264                         acpi_video_bus_unregister_backlight(video);
2265                 mutex_unlock(&video_list_lock);
2266         }
2267         mutex_unlock(&register_count_mutex);
2268 }
2269
2270 bool acpi_video_handles_brightness_key_presses(void)
2271 {
2272         bool have_video_busses;
2273
2274         mutex_lock(&video_list_lock);
2275         have_video_busses = !list_empty(&video_bus_head);
2276         mutex_unlock(&video_list_lock);
2277
2278         return have_video_busses &&
2279                (report_key_events & REPORT_BRIGHTNESS_KEY_EVENTS);
2280 }
2281 EXPORT_SYMBOL(acpi_video_handles_brightness_key_presses);
2282
2283 /*
2284  * This is kind of nasty. Hardware using Intel chipsets may require
2285  * the video opregion code to be run first in order to initialise
2286  * state before any ACPI video calls are made. To handle this we defer
2287  * registration of the video class until the opregion code has run.
2288  */
2289
2290 static int __init acpi_video_init(void)
2291 {
2292         /*
2293          * Let the module load even if ACPI is disabled (e.g. due to
2294          * a broken BIOS) so that i915.ko can still be loaded on such
2295          * old systems without an AcpiOpRegion.
2296          *
2297          * acpi_video_register() will report -ENODEV later as well due
2298          * to acpi_disabled when i915.ko tries to register itself afterwards.
2299          */
2300         if (acpi_disabled)
2301                 return 0;
2302
2303         if (intel_opregion_present())
2304                 return 0;
2305
2306         return acpi_video_register();
2307 }
2308
2309 static void __exit acpi_video_exit(void)
2310 {
2311         acpi_video_detect_exit();
2312         acpi_video_unregister();
2313
2314         return;
2315 }
2316
2317 module_init(acpi_video_init);
2318 module_exit(acpi_video_exit);