drivers/acpi/video.c

   1 /*
   2  *  video.c - ACPI Video Driver ($Revision:$)
   3  *
   4  *  Copyright (C) 2004 Luming Yu <luming.yu@intel.com>
   5  *  Copyright (C) 2004 Bruno Ducrot <ducrot@poupinou.org>
   6  *  Copyright (C) 2006 Thomas Tuttle <linux-kernel@ttuttle.net>
   7  *
   8  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   9  *
  10  *  This program is free software; you can redistribute it and/or modify
  11  *  it under the terms of the GNU General Public License as published by
  12  *  the Free Software Foundation; either version 2 of the License, or (at
  13  *  your option) any later version.
  14  *
  15  *  This program is distributed in the hope that it will be useful, but
  16  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  17  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  *  General Public License for more details.
  19  *
  20  *  You should have received a copy of the GNU General Public License along
  21  *  with this program; if not, write to the Free Software Foundation, Inc.,
  22  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  23  *
  24  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  25  */
  26
  27 #include <linux/kernel.h>
  28 #include <linux/module.h>
  29 #include <linux/init.h>
  30 #include <linux/types.h>
  31 #include <linux/list.h>
  32 #include <linux/mutex.h>
  33 #include <linux/input.h>
  34 #include <linux/backlight.h>
  35 #include <linux/thermal.h>
  36 #include <linux/sort.h>
  37 #include <linux/pci.h>
  38 #include <linux/pci_ids.h>
  39 #include <linux/slab.h>
  40 #include <asm/uaccess.h>
  41 #include <linux/dmi.h>
  42 #include <acpi/acpi_bus.h>
  43 #include <acpi/acpi_drivers.h>
  44 #include <linux/suspend.h>
  45 #include <acpi/video.h>
  46
  47 #define PREFIX "ACPI: "
  48
  49 #define ACPI_VIDEO_BUS_NAME             "Video Bus"
  50 #define ACPI_VIDEO_DEVICE_NAME          "Video Device"
  51 #define ACPI_VIDEO_NOTIFY_SWITCH        0x80
  52 #define ACPI_VIDEO_NOTIFY_PROBE         0x81
  53 #define ACPI_VIDEO_NOTIFY_CYCLE         0x82
  54 #define ACPI_VIDEO_NOTIFY_NEXT_OUTPUT   0x83
  55 #define ACPI_VIDEO_NOTIFY_PREV_OUTPUT   0x84
  56
  57 #define ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS      0x85
  58 #define ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS        0x86
  59 #define ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS        0x87
  60 #define ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS       0x88
  61 #define ACPI_VIDEO_NOTIFY_DISPLAY_OFF           0x89
  62
  63 #define MAX_NAME_LEN    20
  64
  65 #define _COMPONENT              ACPI_VIDEO_COMPONENT
  66 ACPI_MODULE_NAME("video");
  67
  68 MODULE_AUTHOR("Bruno Ducrot");
  69 MODULE_DESCRIPTION("ACPI Video Driver");
  70 MODULE_LICENSE("GPL");
  71
  72 static bool brightness_switch_enabled = 1;
  73 module_param(brightness_switch_enabled, bool, 0644);
  74
  75 /*
  76  * By default, we don't allow duplicate ACPI video bus devices
  77  * under the same VGA controller
  78  */
  79 static bool allow_duplicates;
  80 module_param(allow_duplicates, bool, 0644);
  81
  82 /*
  83  * Some BIOSes claim they use minimum backlight at boot,
  84  * and this may bring dimming screen after boot
  85  */
  86 static bool use_bios_initial_backlight = 1;
  87 module_param(use_bios_initial_backlight, bool, 0644);
  88
  89 static int register_count = 0;
  90 static int acpi_video_bus_add(struct acpi_device *device);
  91 static int acpi_video_bus_remove(struct acpi_device *device);
  92 static void acpi_video_bus_notify(struct acpi_device *device, u32 event);
  93
  94 static const struct acpi_device_id video_device_ids[] = {
  95         {ACPI_VIDEO_HID, 0},
  96         {"", 0},
  97 };
  98 MODULE_DEVICE_TABLE(acpi, video_device_ids);
  99
 100 static struct acpi_driver acpi_video_bus = {
 101         .name = "video",
 102         .class = ACPI_VIDEO_CLASS,
 103         .ids = video_device_ids,
 104         .ops = {
 105                 .add = acpi_video_bus_add,
 106                 .remove = acpi_video_bus_remove,
 107                 .notify = acpi_video_bus_notify,
 108                 },
 109 };
 110
 111 struct acpi_video_bus_flags {
 112         u8 multihead:1;         /* can switch video heads */
 113         u8 rom:1;               /* can retrieve a video rom */
 114         u8 post:1;              /* can configure the head to */
 115         u8 reserved:5;
 116 };
 117
 118 struct acpi_video_bus_cap {
 119         u8 _DOS:1;              /*Enable/Disable output switching */
 120         u8 _DOD:1;              /*Enumerate all devices attached to display adapter */
 121         u8 _ROM:1;              /*Get ROM Data */
 122         u8 _GPD:1;              /*Get POST Device */
 123         u8 _SPD:1;              /*Set POST Device */
 124         u8 _VPO:1;              /*Video POST Options */
 125         u8 reserved:2;
 126 };
 127
 128 struct acpi_video_device_attrib {
 129         u32 display_index:4;    /* A zero-based instance of the Display */
 130         u32 display_port_attachment:4;  /*This field differentiates the display type */
 131         u32 display_type:4;     /*Describe the specific type in use */
 132         u32 vendor_specific:4;  /*Chipset Vendor Specific */
 133         u32 bios_can_detect:1;  /*BIOS can detect the device */
 134         u32 depend_on_vga:1;    /*Non-VGA output device whose power is related to
 135                                    the VGA device. */
 136         u32 pipe_id:3;          /*For VGA multiple-head devices. */
 137         u32 reserved:10;        /*Must be 0 */
 138         u32 device_id_scheme:1; /*Device ID Scheme */
 139 };
 140
 141 struct acpi_video_enumerated_device {
 142         union {
 143                 u32 int_val;
 144                 struct acpi_video_device_attrib attrib;
 145         } value;
 146         struct acpi_video_device *bind_info;
 147 };
 148
 149 struct acpi_video_bus {
 150         struct acpi_device *device;
 151         u8 dos_setting;
 152         struct acpi_video_enumerated_device *attached_array;
 153         u8 attached_count;
 154         struct acpi_video_bus_cap cap;
 155         struct acpi_video_bus_flags flags;
 156         struct list_head video_device_list;
 157         struct mutex device_list_lock;  /* protects video_device_list */
 158         struct input_dev *input;
 159         char phys[32];  /* for input device */
 160         struct notifier_block pm_nb;
 161 };
 162
 163 struct acpi_video_device_flags {
 164         u8 crt:1;
 165         u8 lcd:1;
 166         u8 tvout:1;
 167         u8 dvi:1;
 168         u8 bios:1;
 169         u8 unknown:1;
 170         u8 notify:1;
 171         u8 reserved:1;
 172 };
 173
 174 struct acpi_video_device_cap {
 175         u8 _ADR:1;              /*Return the unique ID */
 176         u8 _BCL:1;              /*Query list of brightness control levels supported */
 177         u8 _BCM:1;              /*Set the brightness level */
 178         u8 _BQC:1;              /* Get current brightness level */
 179         u8 _BCQ:1;              /* Some buggy BIOS uses _BCQ instead of _BQC */
 180         u8 _DDC:1;              /*Return the EDID for this device */
 181 };
 182
 183 struct acpi_video_brightness_flags {
 184         u8 _BCL_no_ac_battery_levels:1; /* no AC/Battery levels in _BCL */
 185         u8 _BCL_reversed:1;             /* _BCL package is in a reversed order*/
 186         u8 _BCL_use_index:1;            /* levels in _BCL are index values */
 187         u8 _BCM_use_index:1;            /* input of _BCM is an index value */
 188         u8 _BQC_use_index:1;            /* _BQC returns an index value */
 189 };
 190
 191 struct acpi_video_device_brightness {
 192         int curr;
 193         int count;
 194         int *levels;
 195         struct acpi_video_brightness_flags flags;
 196 };
 197
 198 struct acpi_video_device {
 199         unsigned long device_id;
 200         struct acpi_video_device_flags flags;
 201         struct acpi_video_device_cap cap;
 202         struct list_head entry;
 203         struct acpi_video_bus *video;
 204         struct acpi_device *dev;
 205         struct acpi_video_device_brightness *brightness;
 206         struct backlight_device *backlight;
 207         struct thermal_cooling_device *cooling_dev;
 208 };
 209
 210 static const char device_decode[][30] = {
 211         "motherboard VGA device",
 212         "PCI VGA device",
 213         "AGP VGA device",
 214         "UNKNOWN",
 215 };
 216
 217 static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data);
 218 static void acpi_video_device_rebind(struct acpi_video_bus *video);
 219 static void acpi_video_device_bind(struct acpi_video_bus *video,
 220                                    struct acpi_video_device *device);
 221 static int acpi_video_device_enumerate(struct acpi_video_bus *video);
 222 static int acpi_video_device_lcd_set_level(struct acpi_video_device *device,
 223                         int level);
 224 static int acpi_video_device_lcd_get_level_current(
 225                         struct acpi_video_device *device,
 226                         unsigned long long *level, bool raw);
 227 static int acpi_video_get_next_level(struct acpi_video_device *device,
 228                                      u32 level_current, u32 event);
 229 static int acpi_video_switch_brightness(struct acpi_video_device *device,
 230                                          int event);
 231
 232 /*backlight device sysfs support*/
 233 static int acpi_video_get_brightness(struct backlight_device *bd)
 234 {
 235         unsigned long long cur_level;
 236         int i;
 237         struct acpi_video_device *vd =
 238                 (struct acpi_video_device *)bl_get_data(bd);
 239
 240         if (acpi_video_device_lcd_get_level_current(vd, &cur_level, false))
 241                 return -EINVAL;
 242         for (i = 2; i < vd->brightness->count; i++) {
 243                 if (vd->brightness->levels[i] == cur_level)
 244                         /* The first two entries are special - see page 575
 245                            of the ACPI spec 3.0 */
 246                         return i-2;
 247         }
 248         return 0;
 249 }
 250
 251 static int acpi_video_set_brightness(struct backlight_device *bd)
 252 {
 253         int request_level = bd->props.brightness + 2;
 254         struct acpi_video_device *vd =
 255                 (struct acpi_video_device *)bl_get_data(bd);
 256
 257         return acpi_video_device_lcd_set_level(vd,
 258                                 vd->brightness->levels[request_level]);
 259 }
 260
 261 static const struct backlight_ops acpi_backlight_ops = {
 262         .get_brightness = acpi_video_get_brightness,
 263         .update_status  = acpi_video_set_brightness,
 264 };
 265
 266 /* thermal cooling device callbacks */
 267 static int video_get_max_state(struct thermal_cooling_device *cooling_dev, unsigned
 268                                long *state)
 269 {
 270         struct acpi_device *device = cooling_dev->devdata;
 271         struct acpi_video_device *video = acpi_driver_data(device);
 272
 273         *state = video->brightness->count - 3;
 274         return 0;
 275 }
 276
 277 static int video_get_cur_state(struct thermal_cooling_device *cooling_dev, unsigned
 278                                long *state)
 279 {
 280         struct acpi_device *device = cooling_dev->devdata;
 281         struct acpi_video_device *video = acpi_driver_data(device);
 282         unsigned long long level;
 283         int offset;
 284
 285         if (acpi_video_device_lcd_get_level_current(video, &level, false))
 286                 return -EINVAL;
 287         for (offset = 2; offset < video->brightness->count; offset++)
 288                 if (level == video->brightness->levels[offset]) {
 289                         *state = video->brightness->count - offset - 1;
 290                         return 0;
 291                 }
 292
 293         return -EINVAL;
 294 }
 295
 296 static int
 297 video_set_cur_state(struct thermal_cooling_device *cooling_dev, unsigned long state)
 298 {
 299         struct acpi_device *device = cooling_dev->devdata;
 300         struct acpi_video_device *video = acpi_driver_data(device);
 301         int level;
 302
 303         if ( state >= video->brightness->count - 2)
 304                 return -EINVAL;
 305
 306         state = video->brightness->count - state;
 307         level = video->brightness->levels[state -1];
 308         return acpi_video_device_lcd_set_level(video, level);
 309 }
 310
 311 static const struct thermal_cooling_device_ops video_cooling_ops = {
 312         .get_max_state = video_get_max_state,
 313         .get_cur_state = video_get_cur_state,
 314         .set_cur_state = video_set_cur_state,
 315 };
 316
 317 /* --------------------------------------------------------------------------
 318                                Video Management
 319    -------------------------------------------------------------------------- */
 320
 321 static int
 322 acpi_video_device_lcd_query_levels(struct acpi_video_device *device,
 323                                    union acpi_object **levels)
 324 {
 325         int status;
 326         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 327         union acpi_object *obj;
 328
 329
 330         *levels = NULL;
 331
 332         status = acpi_evaluate_object(device->dev->handle, "_BCL", NULL, &buffer);
 333         if (!ACPI_SUCCESS(status))
 334                 return status;
 335         obj = (union acpi_object *)buffer.pointer;
 336         if (!obj || (obj->type != ACPI_TYPE_PACKAGE)) {
 337                 printk(KERN_ERR PREFIX "Invalid _BCL data\n");
 338                 status = -EFAULT;
 339                 goto err;
 340         }
 341
 342         *levels = obj;
 343
 344         return 0;
 345
 346       err:
 347         kfree(buffer.pointer);
 348
 349         return status;
 350 }
 351
 352 static int
 353 acpi_video_device_lcd_set_level(struct acpi_video_device *device, int level)
 354 {
 355         int status;
 356         union acpi_object arg0 = { ACPI_TYPE_INTEGER };
 357         struct acpi_object_list args = { 1, &arg0 };
 358         int state;
 359
 360         arg0.integer.value = level;
 361
 362         status = acpi_evaluate_object(device->dev->handle, "_BCM",
 363                                       &args, NULL);
 364         if (ACPI_FAILURE(status)) {
 365                 ACPI_ERROR((AE_INFO, "Evaluating _BCM failed"));
 366                 return -EIO;
 367         }
 368
 369         device->brightness->curr = level;
 370         for (state = 2; state < device->brightness->count; state++)
 371                 if (level == device->brightness->levels[state]) {
 372                         if (device->backlight)
 373                                 device->backlight->props.brightness = state - 2;
 374                         return 0;
 375                 }
 376
 377         ACPI_ERROR((AE_INFO, "Current brightness invalid"));
 378         return -EINVAL;
 379 }
 380
 381 /*
 382  * For some buggy _BQC methods, we need to add a constant value to
 383  * the _BQC return value to get the actual current brightness level
 384  */
 385
 386 static int bqc_offset_aml_bug_workaround;
 387 static int __init video_set_bqc_offset(const struct dmi_system_id *d)
 388 {
 389         bqc_offset_aml_bug_workaround = 9;
 390         return 0;
 391 }
 392
 393 static int video_ignore_initial_backlight(const struct dmi_system_id *d)
 394 {
 395         use_bios_initial_backlight = 0;
 396         return 0;
 397 }
 398
 399 static struct dmi_system_id video_dmi_table[] __initdata = {
 400         /*
 401          * Broken _BQC workaround http://bugzilla.kernel.org/show_bug.cgi?id=13121
 402          */
 403         {
 404          .callback = video_set_bqc_offset,
 405          .ident = "Acer Aspire 5720",
 406          .matches = {
 407                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
 408                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5720"),
 409                 },
 410         },
 411         {
 412          .callback = video_set_bqc_offset,
 413          .ident = "Acer Aspire 5710Z",
 414          .matches = {
 415                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
 416                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5710Z"),
 417                 },
 418         },
 419         {
 420          .callback = video_set_bqc_offset,
 421          .ident = "eMachines E510",
 422          .matches = {
 423                 DMI_MATCH(DMI_BOARD_VENDOR, "EMACHINES"),
 424                 DMI_MATCH(DMI_PRODUCT_NAME, "eMachines E510"),
 425                 },
 426         },
 427         {
 428          .callback = video_set_bqc_offset,
 429          .ident = "Acer Aspire 5315",
 430          .matches = {
 431                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
 432                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5315"),
 433                 },
 434         },
 435         {
 436          .callback = video_set_bqc_offset,
 437          .ident = "Acer Aspire 7720",
 438          .matches = {
 439                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
 440                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 7720"),
 441                 },
 442         },
 443         {
 444          .callback = video_ignore_initial_backlight,
 445          .ident = "HP Folio 13-2000",
 446          .matches = {
 447                 DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
 448                 DMI_MATCH(DMI_PRODUCT_NAME, "HP Folio 13 - 2000 Notebook PC"),
 449                 },
 450         },
 451         {
 452          .callback = video_ignore_initial_backlight,
 453          .ident = "Fujitsu E753",
 454          .matches = {
 455                 DMI_MATCH(DMI_BOARD_VENDOR, "FUJITSU"),
 456                 DMI_MATCH(DMI_PRODUCT_NAME, "LIFEBOOK E753"),
 457                 },
 458         },
 459         {
 460          .callback = video_ignore_initial_backlight,
 461          .ident = "HP Pavilion dm4",
 462          .matches = {
 463                 DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
 464                 DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion dm4 Notebook PC"),
 465                 },
 466         },
 467         {
 468          .callback = video_ignore_initial_backlight,
 469          .ident = "HP Pavilion g6 Notebook PC",
 470          .matches = {
 471                  DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
 472                  DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion g6 Notebook PC"),
 473                 },
 474         },
 475         {
 476          .callback = video_ignore_initial_backlight,
 477          .ident = "HP 1000 Notebook PC",
 478          .matches = {
 479                 DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
 480                 DMI_MATCH(DMI_PRODUCT_NAME, "HP 1000 Notebook PC"),
 481                 },
 482         },
 483         {
 484          .callback = video_ignore_initial_backlight,
 485          .ident = "HP Pavilion m4",
 486          .matches = {
 487                 DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
 488                 DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion m4 Notebook PC"),
 489                 },
 490         },
 491         {}
 492 };
 493
 494 static unsigned long long
 495 acpi_video_bqc_value_to_level(struct acpi_video_device *device,
 496                               unsigned long long bqc_value)
 497 {
 498         unsigned long long level;
 499
 500         if (device->brightness->flags._BQC_use_index) {
 501                 /*
 502                  * _BQC returns an index that doesn't account for
 503                  * the first 2 items with special meaning, so we need
 504                  * to compensate for that by offsetting ourselves
 505                  */
 506                 if (device->brightness->flags._BCL_reversed)
 507                         bqc_value = device->brightness->count - 3 - bqc_value;
 508
 509                 level = device->brightness->levels[bqc_value + 2];
 510         } else {
 511                 level = bqc_value;
 512         }
 513
 514         level += bqc_offset_aml_bug_workaround;
 515
 516         return level;
 517 }
 518
 519 static int
 520 acpi_video_device_lcd_get_level_current(struct acpi_video_device *device,
 521                                         unsigned long long *level, bool raw)
 522 {
 523         acpi_status status = AE_OK;
 524         int i;
 525
 526         if (device->cap._BQC || device->cap._BCQ) {
 527                 char *buf = device->cap._BQC ? "_BQC" : "_BCQ";
 528
 529                 status = acpi_evaluate_integer(device->dev->handle, buf,
 530                                                 NULL, level);
 531                 if (ACPI_SUCCESS(status)) {
 532                         if (raw) {
 533                                 /*
 534                                  * Caller has indicated he wants the raw
 535                                  * value returned by _BQC, so don't furtherly
 536                                  * mess with the value.
 537                                  */
 538                                 return 0;
 539                         }
 540
 541                         *level = acpi_video_bqc_value_to_level(device, *level);
 542
 543                         for (i = 2; i < device->brightness->count; i++)
 544                                 if (device->brightness->levels[i] == *level) {
 545                                         device->brightness->curr = *level;
 546                                         return 0;
 547                         }
 548                         /*
 549                          * BQC returned an invalid level.
 550                          * Stop using it.
 551                          */
 552                         ACPI_WARNING((AE_INFO,
 553                                       "%s returned an invalid level",
 554                                       buf));
 555                         device->cap._BQC = device->cap._BCQ = 0;
 556                 } else {
 557                         /* Fixme:
 558                          * should we return an error or ignore this failure?
 559                          * dev->brightness->curr is a cached value which stores
 560                          * the correct current backlight level in most cases.
 561                          * ACPI video backlight still works w/ buggy _BQC.
 562                          * http://bugzilla.kernel.org/show_bug.cgi?id=12233
 563                          */
 564                         ACPI_WARNING((AE_INFO, "Evaluating %s failed", buf));
 565                         device->cap._BQC = device->cap._BCQ = 0;
 566                 }
 567         }
 568
 569         *level = device->brightness->curr;
 570         return 0;
 571 }
 572
 573 static int
 574 acpi_video_device_EDID(struct acpi_video_device *device,
 575                        union acpi_object **edid, ssize_t length)
 576 {
 577         int status;
 578         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 579         union acpi_object *obj;
 580         union acpi_object arg0 = { ACPI_TYPE_INTEGER };
 581         struct acpi_object_list args = { 1, &arg0 };
 582
 583
 584         *edid = NULL;
 585
 586         if (!device)
 587                 return -ENODEV;
 588         if (length == 128)
 589                 arg0.integer.value = 1;
 590         else if (length == 256)
 591                 arg0.integer.value = 2;
 592         else
 593                 return -EINVAL;
 594
 595         status = acpi_evaluate_object(device->dev->handle, "_DDC", &args, &buffer);
 596         if (ACPI_FAILURE(status))
 597                 return -ENODEV;
 598
 599         obj = buffer.pointer;
 600
 601         if (obj && obj->type == ACPI_TYPE_BUFFER)
 602                 *edid = obj;
 603         else {
 604                 printk(KERN_ERR PREFIX "Invalid _DDC data\n");
 605                 status = -EFAULT;
 606                 kfree(obj);
 607         }
 608
 609         return status;
 610 }
 611
 612 /* bus */
 613
 614 /*
 615  *  Arg:
 616  *      video           : video bus device pointer
 617  *      bios_flag       :
 618  *              0.      The system BIOS should NOT automatically switch(toggle)
 619  *                      the active display output.
 620  *              1.      The system BIOS should automatically switch (toggle) the
 621  *                      active display output. No switch event.
 622  *              2.      The _DGS value should be locked.
 623  *              3.      The system BIOS should not automatically switch (toggle) the
 624  *                      active display output, but instead generate the display switch
 625  *                      event notify code.
 626  *      lcd_flag        :
 627  *              0.      The system BIOS should automatically control the brightness level
 628  *                      of the LCD when the power changes from AC to DC
 629  *              1.      The system BIOS should NOT automatically control the brightness
 630  *                      level of the LCD when the power changes from AC to DC.
 631  * Return Value:
 632  *              -EINVAL wrong arg.
 633  */
 634
 635 static int
 636 acpi_video_bus_DOS(struct acpi_video_bus *video, int bios_flag, int lcd_flag)
 637 {
 638         acpi_status status;
 639         union acpi_object arg0 = { ACPI_TYPE_INTEGER };
 640         struct acpi_object_list args = { 1, &arg0 };
 641
 642         if (!video->cap._DOS)
 643                 return 0;
 644
 645         if (bios_flag < 0 || bios_flag > 3 || lcd_flag < 0 || lcd_flag > 1)
 646                 return -EINVAL;
 647         arg0.integer.value = (lcd_flag << 2) | bios_flag;
 648         video->dos_setting = arg0.integer.value;
 649         status = acpi_evaluate_object(video->device->handle, "_DOS",
 650                 &args, NULL);
 651         if (ACPI_FAILURE(status))
 652                 return -EIO;
 653
 654         return 0;
 655 }
 656
 657 /*
 658  * Simple comparison function used to sort backlight levels.
 659  */
 660
 661 static int
 662 acpi_video_cmp_level(const void *a, const void *b)
 663 {
 664         return *(int *)a - *(int *)b;
 665 }
 666
 667 /*
 668  * Decides if _BQC/_BCQ for this system is usable
 669  *
 670  * We do this by changing the level first and then read out the current
 671  * brightness level, if the value does not match, find out if it is using
 672  * index. If not, clear the _BQC/_BCQ capability.
 673  */
 674 static int acpi_video_bqc_quirk(struct acpi_video_device *device,
 675                                 int max_level, int current_level)
 676 {
 677         struct acpi_video_device_brightness *br = device->brightness;
 678         int result;
 679         unsigned long long level;
 680         int test_level;
 681
 682         /* don't mess with existing known broken systems */
 683         if (bqc_offset_aml_bug_workaround)
 684                 return 0;
 685
 686         /*
 687          * Some systems always report current brightness level as maximum
 688          * through _BQC, we need to test another value for them.
 689          */
 690         test_level = current_level == max_level ? br->levels[2] : max_level;
 691
 692         result = acpi_video_device_lcd_set_level(device, test_level);
 693         if (result)
 694                 return result;
 695
 696         result = acpi_video_device_lcd_get_level_current(device, &level, true);
 697         if (result)
 698                 return result;
 699
 700         if (level != test_level) {
 701                 /* buggy _BQC found, need to find out if it uses index */
 702                 if (level < br->count) {
 703                         if (br->flags._BCL_reversed)
 704                                 level = br->count - 3 - level;
 705                         if (br->levels[level + 2] == test_level)
 706                                 br->flags._BQC_use_index = 1;
 707                 }
 708
 709                 if (!br->flags._BQC_use_index)
 710                         device->cap._BQC = device->cap._BCQ = 0;
 711         }
 712
 713         return 0;
 714 }
 715
 716
 717 /*
 718  *  Arg:
 719  *      device  : video output device (LCD, CRT, ..)
 720  *
 721  *  Return Value:
 722  *      Maximum brightness level
 723  *
 724  *  Allocate and initialize device->brightness.
 725  */
 726
 727 static int
 728 acpi_video_init_brightness(struct acpi_video_device *device)
 729 {
 730         union acpi_object *obj = NULL;
 731         int i, max_level = 0, count = 0, level_ac_battery = 0;
 732         unsigned long long level, level_old;
 733         union acpi_object *o;
 734         struct acpi_video_device_brightness *br = NULL;
 735         int result = -EINVAL;
 736
 737         if (!ACPI_SUCCESS(acpi_video_device_lcd_query_levels(device, &obj))) {
 738                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Could not query available "
 739                                                 "LCD brightness level\n"));
 740                 goto out;
 741         }
 742
 743         if (obj->package.count < 2)
 744                 goto out;
 745
 746         br = kzalloc(sizeof(*br), GFP_KERNEL);
 747         if (!br) {
 748                 printk(KERN_ERR "can't allocate memory\n");
 749                 result = -ENOMEM;
 750                 goto out;
 751         }
 752
 753         br->levels = kmalloc((obj->package.count + 2) * sizeof *(br->levels),
 754                                 GFP_KERNEL);
 755         if (!br->levels) {
 756                 result = -ENOMEM;
 757                 goto out_free;
 758         }
 759
 760         for (i = 0; i < obj->package.count; i++) {
 761                 o = (union acpi_object *)&obj->package.elements[i];
 762                 if (o->type != ACPI_TYPE_INTEGER) {
 763                         printk(KERN_ERR PREFIX "Invalid data\n");
 764                         continue;
 765                 }
 766                 br->levels[count] = (u32) o->integer.value;
 767
 768                 if (br->levels[count] > max_level)
 769                         max_level = br->levels[count];
 770                 count++;
 771         }
 772
 773         /*
 774          * some buggy BIOS don't export the levels
 775          * when machine is on AC/Battery in _BCL package.
 776          * In this case, the first two elements in _BCL packages
 777          * are also supported brightness levels that OS should take care of.
 778          */
 779         for (i = 2; i < count; i++) {
 780                 if (br->levels[i] == br->levels[0])
 781                         level_ac_battery++;
 782                 if (br->levels[i] == br->levels[1])
 783                         level_ac_battery++;
 784         }
 785
 786         if (level_ac_battery < 2) {
 787                 level_ac_battery = 2 - level_ac_battery;
 788                 br->flags._BCL_no_ac_battery_levels = 1;
 789                 for (i = (count - 1 + level_ac_battery); i >= 2; i--)
 790                         br->levels[i] = br->levels[i - level_ac_battery];
 791                 count += level_ac_battery;
 792         } else if (level_ac_battery > 2)
 793                 ACPI_ERROR((AE_INFO, "Too many duplicates in _BCL package"));
 794
 795         /* Check if the _BCL package is in a reversed order */
 796         if (max_level == br->levels[2]) {
 797                 br->flags._BCL_reversed = 1;
 798                 sort(&br->levels[2], count - 2, sizeof(br->levels[2]),
 799                         acpi_video_cmp_level, NULL);
 800         } else if (max_level != br->levels[count - 1])
 801                 ACPI_ERROR((AE_INFO,
 802                             "Found unordered _BCL package"));
 803
 804         br->count = count;
 805         device->brightness = br;
 806
 807         /* Check the input/output of _BQC/_BCL/_BCM */
 808         if ((max_level < 100) && (max_level <= (count - 2)))
 809                 br->flags._BCL_use_index = 1;
 810
 811         /*
 812          * _BCM is always consistent with _BCL,
 813          * at least for all the laptops we have ever seen.
 814          */
 815         br->flags._BCM_use_index = br->flags._BCL_use_index;
 816
 817         /* _BQC uses INDEX while _BCL uses VALUE in some laptops */
 818         br->curr = level = max_level;
 819
 820         if (!device->cap._BQC)
 821                 goto set_level;
 822
 823         result = acpi_video_device_lcd_get_level_current(device,
 824                                                          &level_old, true);
 825         if (result)
 826                 goto out_free_levels;
 827
 828         result = acpi_video_bqc_quirk(device, max_level, level_old);
 829         if (result)
 830                 goto out_free_levels;
 831         /*
 832          * cap._BQC may get cleared due to _BQC is found to be broken
 833          * in acpi_video_bqc_quirk, so check again here.
 834          */
 835         if (!device->cap._BQC)
 836                 goto set_level;
 837
 838         if (use_bios_initial_backlight) {
 839                 level = acpi_video_bqc_value_to_level(device, level_old);
 840                 /*
 841                  * On some buggy laptops, _BQC returns an uninitialized
 842                  * value when invoked for the first time, i.e.
 843                  * level_old is invalid (no matter whether it's a level
 844                  * or an index). Set the backlight to max_level in this case.
 845                  */
 846                 for (i = 2; i < br->count; i++)
 847                         if (level_old == br->levels[i])
 848                                 break;
 849                 if (i == br->count)
 850                         level = max_level;
 851         }
 852
 853 set_level:
 854         result = acpi_video_device_lcd_set_level(device, level);
 855         if (result)
 856                 goto out_free_levels;
 857
 858         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 859                           "found %d brightness levels\n", count - 2));
 860         kfree(obj);
 861         return result;
 862
 863 out_free_levels:
 864         kfree(br->levels);
 865 out_free:
 866         kfree(br);
 867 out:
 868         device->brightness = NULL;
 869         kfree(obj);
 870         return result;
 871 }
 872
 873 /*
 874  *  Arg:
 875  *      device  : video output device (LCD, CRT, ..)
 876  *
 877  *  Return Value:
 878  *      None
 879  *
 880  *  Find out all required AML methods defined under the output
 881  *  device.
 882  */
 883
 884 static void acpi_video_device_find_cap(struct acpi_video_device *device)
 885 {
 886         acpi_handle h_dummy1;
 887
 888         if (ACPI_SUCCESS(acpi_get_handle(device->dev->handle, "_ADR", &h_dummy1))) {
 889                 device->cap._ADR = 1;
 890         }
 891         if (ACPI_SUCCESS(acpi_get_handle(device->dev->handle, "_BCL", &h_dummy1))) {
 892                 device->cap._BCL = 1;
 893         }
 894         if (ACPI_SUCCESS(acpi_get_handle(device->dev->handle, "_BCM", &h_dummy1))) {
 895                 device->cap._BCM = 1;
 896         }
 897         if (ACPI_SUCCESS(acpi_get_handle(device->dev->handle,"_BQC",&h_dummy1)))
 898                 device->cap._BQC = 1;
 899         else if (ACPI_SUCCESS(acpi_get_handle(device->dev->handle, "_BCQ",
 900                                 &h_dummy1))) {
 901                 printk(KERN_WARNING FW_BUG "_BCQ is used instead of _BQC\n");
 902                 device->cap._BCQ = 1;
 903         }
 904
 905         if (ACPI_SUCCESS(acpi_get_handle(device->dev->handle, "_DDC", &h_dummy1))) {
 906                 device->cap._DDC = 1;
 907         }
 908
 909         if (acpi_video_backlight_support()) {
 910                 struct backlight_properties props;
 911                 struct pci_dev *pdev;
 912                 acpi_handle acpi_parent;
 913                 struct device *parent = NULL;
 914                 int result;
 915                 static int count = 0;
 916                 char *name;
 917
 918                 result = acpi_video_init_brightness(device);
 919                 if (result)
 920                         return;
 921                 name = kasprintf(GFP_KERNEL, "acpi_video%d", count);
 922                 if (!name)
 923                         return;
 924                 count++;
 925
 926                 acpi_get_parent(device->dev->handle, &acpi_parent);
 927
 928                 pdev = acpi_get_pci_dev(acpi_parent);
 929                 if (pdev) {
 930                         parent = &pdev->dev;
 931                         pci_dev_put(pdev);
 932                 }
 933
 934                 memset(&props, 0, sizeof(struct backlight_properties));
 935                 props.type = BACKLIGHT_FIRMWARE;
 936                 props.max_brightness = device->brightness->count - 3;
 937                 device->backlight = backlight_device_register(name,
 938                                                               parent,
 939                                                               device,
 940                                                               &acpi_backlight_ops,
 941                                                               &props);
 942                 kfree(name);
 943                 if (IS_ERR(device->backlight))
 944                         return;
 945
 946                 /*
 947                  * Save current brightness level in case we have to restore it
 948                  * before acpi_video_device_lcd_set_level() is called next time.
 949                  */
 950                 device->backlight->props.brightness =
 951                                 acpi_video_get_brightness(device->backlight);
 952
 953                 device->cooling_dev = thermal_cooling_device_register("LCD",
 954                                         device->dev, &video_cooling_ops);
 955                 if (IS_ERR(device->cooling_dev)) {
 956                         /*
 957                          * Set cooling_dev to NULL so we don't crash trying to
 958                          * free it.
 959                          * Also, why the hell we are returning early and
 960                          * not attempt to register video output if cooling
 961                          * device registration failed?
 962                          * -- dtor
 963                          */
 964                         device->cooling_dev = NULL;
 965                         return;
 966                 }
 967
 968                 dev_info(&device->dev->dev, "registered as cooling_device%d\n",
 969                          device->cooling_dev->id);
 970                 result = sysfs_create_link(&device->dev->dev.kobj,
 971                                 &device->cooling_dev->device.kobj,
 972                                 "thermal_cooling");
 973                 if (result)
 974                         printk(KERN_ERR PREFIX "Create sysfs link\n");
 975                 result = sysfs_create_link(&device->cooling_dev->device.kobj,
 976                                 &device->dev->dev.kobj, "device");
 977                 if (result)
 978                         printk(KERN_ERR PREFIX "Create sysfs link\n");
 979
 980         }
 981 }
 982
 983 /*
 984  *  Arg:
 985  *      device  : video output device (VGA)
 986  *
 987  *  Return Value:
 988  *      None
 989  *
 990  *  Find out all required AML methods defined under the video bus device.
 991  */
 992
 993 static void acpi_video_bus_find_cap(struct acpi_video_bus *video)
 994 {
 995         acpi_handle h_dummy1;
 996
 997         if (ACPI_SUCCESS(acpi_get_handle(video->device->handle, "_DOS", &h_dummy1))) {
 998                 video->cap._DOS = 1;
 999         }
1000         if (ACPI_SUCCESS(acpi_get_handle(video->device->handle, "_DOD", &h_dummy1))) {
1001                 video->cap._DOD = 1;
1002         }
1003         if (ACPI_SUCCESS(acpi_get_handle(video->device->handle, "_ROM", &h_dummy1))) {
1004                 video->cap._ROM = 1;
1005         }
1006         if (ACPI_SUCCESS(acpi_get_handle(video->device->handle, "_GPD", &h_dummy1))) {
1007                 video->cap._GPD = 1;
1008         }
1009         if (ACPI_SUCCESS(acpi_get_handle(video->device->handle, "_SPD", &h_dummy1))) {
1010                 video->cap._SPD = 1;
1011         }
1012         if (ACPI_SUCCESS(acpi_get_handle(video->device->handle, "_VPO", &h_dummy1))) {
1013                 video->cap._VPO = 1;
1014         }
1015 }
1016
1017 /*
1018  * Check whether the video bus device has required AML method to
1019  * support the desired features
1020  */
1021
1022 static int acpi_video_bus_check(struct acpi_video_bus *video)
1023 {
1024         acpi_status status = -ENOENT;
1025         struct pci_dev *dev;
1026
1027         if (!video)
1028                 return -EINVAL;
1029
1030         dev = acpi_get_pci_dev(video->device->handle);
1031         if (!dev)
1032                 return -ENODEV;
1033         pci_dev_put(dev);
1034
1035         /* Since there is no HID, CID and so on for VGA driver, we have
1036          * to check well known required nodes.
1037          */
1038
1039         /* Does this device support video switching? */
1040         if (video->cap._DOS || video->cap._DOD) {
1041                 if (!video->cap._DOS) {
1042                         printk(KERN_WARNING FW_BUG
1043                                 "ACPI(%s) defines _DOD but not _DOS\n",
1044                                 acpi_device_bid(video->device));
1045                 }
1046                 video->flags.multihead = 1;
1047                 status = 0;
1048         }
1049
1050         /* Does this device support retrieving a video ROM? */
1051         if (video->cap._ROM) {
1052                 video->flags.rom = 1;
1053                 status = 0;
1054         }
1055
1056         /* Does this device support configuring which video device to POST? */
1057         if (video->cap._GPD && video->cap._SPD && video->cap._VPO) {
1058                 video->flags.post = 1;
1059                 status = 0;
1060         }
1061
1062         return status;
1063 }
1064
1065 /* --------------------------------------------------------------------------
1066                                  Driver Interface
1067    -------------------------------------------------------------------------- */
1068
1069 /* device interface */
1070 static struct acpi_video_device_attrib*
1071 acpi_video_get_device_attr(struct acpi_video_bus *video, unsigned long device_id)
1072 {
1073         struct acpi_video_enumerated_device *ids;
1074         int i;
1075
1076         for (i = 0; i < video->attached_count; i++) {
1077                 ids = &video->attached_array[i];
1078                 if ((ids->value.int_val & 0xffff) == device_id)
1079                         return &ids->value.attrib;
1080         }
1081
1082         return NULL;
1083 }
1084
1085 static int
1086 acpi_video_get_device_type(struct acpi_video_bus *video,
1087                            unsigned long device_id)
1088 {
1089         struct acpi_video_enumerated_device *ids;
1090         int i;
1091
1092         for (i = 0; i < video->attached_count; i++) {
1093                 ids = &video->attached_array[i];
1094                 if ((ids->value.int_val & 0xffff) == device_id)
1095                         return ids->value.int_val;
1096         }
1097
1098         return 0;
1099 }
1100
1101 static int
1102 acpi_video_bus_get_one_device(struct acpi_device *device,
1103                               struct acpi_video_bus *video)
1104 {
1105         unsigned long long device_id;
1106         int status, device_type;
1107         struct acpi_video_device *data;
1108         struct acpi_video_device_attrib* attribute;
1109
1110         status =
1111             acpi_evaluate_integer(device->handle, "_ADR", NULL, &device_id);
1112         /* Some device omits _ADR, we skip them instead of fail */
1113         if (ACPI_FAILURE(status))
1114                 return 0;
1115
1116         data = kzalloc(sizeof(struct acpi_video_device), GFP_KERNEL);
1117         if (!data)
1118                 return -ENOMEM;
1119
1120         strcpy(acpi_device_name(device), ACPI_VIDEO_DEVICE_NAME);
1121         strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
1122         device->driver_data = data;
1123
1124         data->device_id = device_id;
1125         data->video = video;
1126         data->dev = device;
1127
1128         attribute = acpi_video_get_device_attr(video, device_id);
1129
1130         if((attribute != NULL) && attribute->device_id_scheme) {
1131                 switch (attribute->display_type) {
1132                 case ACPI_VIDEO_DISPLAY_CRT:
1133                         data->flags.crt = 1;
1134                         break;
1135                 case ACPI_VIDEO_DISPLAY_TV:
1136                         data->flags.tvout = 1;
1137                         break;
1138                 case ACPI_VIDEO_DISPLAY_DVI:
1139                         data->flags.dvi = 1;
1140                         break;
1141                 case ACPI_VIDEO_DISPLAY_LCD:
1142                         data->flags.lcd = 1;
1143                         break;
1144                 default:
1145                         data->flags.unknown = 1;
1146                         break;
1147                 }
1148                 if(attribute->bios_can_detect)
1149                         data->flags.bios = 1;
1150         } else {
1151                 /* Check for legacy IDs */
1152                 device_type = acpi_video_get_device_type(video, device_id);
1153                 /* Ignore bits 16 and 18-20 */
1154                 switch (device_type & 0xffe2ffff) {
1155                         case ACPI_VIDEO_DISPLAY_LEGACY_MONITOR:
1156                                 data->flags.crt = 1;
1157                                 break;
1158                         case ACPI_VIDEO_DISPLAY_LEGACY_PANEL:
1159                                 data->flags.lcd = 1;
1160                                 break;
1161                         case ACPI_VIDEO_DISPLAY_LEGACY_TV:
1162                                 data->flags.tvout = 1;
1163                                 break;
1164                         default:
1165                                 data->flags.unknown = 1;
1166                 }
1167         }
1168
1169         acpi_video_device_bind(video, data);
1170         acpi_video_device_find_cap(data);
1171
1172         status = acpi_install_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
1173                                              acpi_video_device_notify, data);
1174         if (ACPI_FAILURE(status))
1175                 dev_err(&device->dev, "Error installing notify handler\n");
1176         else
1177                 data->flags.notify = 1;
1178
1179         mutex_lock(&video->device_list_lock);
1180         list_add_tail(&data->entry, &video->video_device_list);
1181         mutex_unlock(&video->device_list_lock);
1182
1183         return status;
1184 }
1185
1186 /*
1187  *  Arg:
1188  *      video   : video bus device
1189  *
1190  *  Return:
1191  *      none
1192  *
1193  *  Enumerate the video device list of the video bus,
1194  *  bind the ids with the corresponding video devices
1195  *  under the video bus.
1196  */
1197
1198 static void acpi_video_device_rebind(struct acpi_video_bus *video)
1199 {
1200         struct acpi_video_device *dev;
1201
1202         mutex_lock(&video->device_list_lock);
1203
1204         list_for_each_entry(dev, &video->video_device_list, entry)
1205                 acpi_video_device_bind(video, dev);
1206
1207         mutex_unlock(&video->device_list_lock);
1208 }
1209
1210 /*
1211  *  Arg:
1212  *      video   : video bus device
1213  *      device  : video output device under the video
1214  *              bus
1215  *
1216  *  Return:
1217  *      none
1218  *
1219  *  Bind the ids with the corresponding video devices
1220  *  under the video bus.
1221  */
1222
1223 static void
1224 acpi_video_device_bind(struct acpi_video_bus *video,
1225                        struct acpi_video_device *device)
1226 {
1227         struct acpi_video_enumerated_device *ids;
1228         int i;
1229
1230         for (i = 0; i < video->attached_count; i++) {
1231                 ids = &video->attached_array[i];
1232                 if (device->device_id == (ids->value.int_val & 0xffff)) {
1233                         ids->bind_info = device;
1234                         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "device_bind %d\n", i));
1235                 }
1236         }
1237 }
1238
1239 /*
1240  *  Arg:
1241  *      video   : video bus device
1242  *
1243  *  Return:
1244  *      < 0     : error
1245  *
1246  *  Call _DOD to enumerate all devices attached to display adapter
1247  *
1248  */
1249
1250 static int acpi_video_device_enumerate(struct acpi_video_bus *video)
1251 {
1252         int status;
1253         int count;
1254         int i;
1255         struct acpi_video_enumerated_device *active_list;
1256         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1257         union acpi_object *dod = NULL;
1258         union acpi_object *obj;
1259
1260         status = acpi_evaluate_object(video->device->handle, "_DOD", NULL, &buffer);
1261         if (!ACPI_SUCCESS(status)) {
1262                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _DOD"));
1263                 return status;
1264         }
1265
1266         dod = buffer.pointer;
1267         if (!dod || (dod->type != ACPI_TYPE_PACKAGE)) {
1268                 ACPI_EXCEPTION((AE_INFO, status, "Invalid _DOD data"));
1269                 status = -EFAULT;
1270                 goto out;
1271         }
1272
1273         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d video heads in _DOD\n",
1274                           dod->package.count));
1275
1276         active_list = kcalloc(1 + dod->package.count,
1277                               sizeof(struct acpi_video_enumerated_device),
1278                               GFP_KERNEL);
1279         if (!active_list) {
1280                 status = -ENOMEM;
1281                 goto out;
1282         }
1283
1284         count = 0;
1285         for (i = 0; i < dod->package.count; i++) {
1286                 obj = &dod->package.elements[i];
1287
1288                 if (obj->type != ACPI_TYPE_INTEGER) {
1289                         printk(KERN_ERR PREFIX
1290                                 "Invalid _DOD data in element %d\n", i);
1291                         continue;
1292                 }
1293
1294                 active_list[count].value.int_val = obj->integer.value;
1295                 active_list[count].bind_info = NULL;
1296                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "dod element[%d] = %d\n", i,
1297                                   (int)obj->integer.value));
1298                 count++;
1299         }
1300
1301         kfree(video->attached_array);
1302
1303         video->attached_array = active_list;
1304         video->attached_count = count;
1305
1306  out:
1307         kfree(buffer.pointer);
1308         return status;
1309 }
1310
1311 static int
1312 acpi_video_get_next_level(struct acpi_video_device *device,
1313                           u32 level_current, u32 event)
1314 {
1315         int min, max, min_above, max_below, i, l, delta = 255;
1316         max = max_below = 0;
1317         min = min_above = 255;
1318         /* Find closest level to level_current */
1319         for (i = 2; i < device->brightness->count; i++) {
1320                 l = device->brightness->levels[i];
1321                 if (abs(l - level_current) < abs(delta)) {
1322                         delta = l - level_current;
1323                         if (!delta)
1324                                 break;
1325                 }
1326         }
1327         /* Ajust level_current to closest available level */
1328         level_current += delta;
1329         for (i = 2; i < device->brightness->count; i++) {
1330                 l = device->brightness->levels[i];
1331                 if (l < min)
1332                         min = l;
1333                 if (l > max)
1334                         max = l;
1335                 if (l < min_above && l > level_current)
1336                         min_above = l;
1337                 if (l > max_below && l < level_current)
1338                         max_below = l;
1339         }
1340
1341         switch (event) {
1342         case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:
1343                 return (level_current < max) ? min_above : min;
1344         case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:
1345                 return (level_current < max) ? min_above : max;
1346         case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:
1347                 return (level_current > min) ? max_below : min;
1348         case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS:
1349         case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:
1350                 return 0;
1351         default:
1352                 return level_current;
1353         }
1354 }
1355
1356 static int
1357 acpi_video_switch_brightness(struct acpi_video_device *device, int event)
1358 {
1359         unsigned long long level_current, level_next;
1360         int result = -EINVAL;
1361
1362         /* no warning message if acpi_backlight=vendor is used */
1363         if (!acpi_video_backlight_support())
1364                 return 0;
1365
1366         if (!device->brightness)
1367                 goto out;
1368
1369         result = acpi_video_device_lcd_get_level_current(device,
1370                                                          &level_current,
1371                                                          false);
1372         if (result)
1373                 goto out;
1374
1375         level_next = acpi_video_get_next_level(device, level_current, event);
1376
1377         result = acpi_video_device_lcd_set_level(device, level_next);
1378
1379         if (!result)
1380                 backlight_force_update(device->backlight,
1381                                        BACKLIGHT_UPDATE_HOTKEY);
1382
1383 out:
1384         if (result)
1385                 printk(KERN_ERR PREFIX "Failed to switch the brightness\n");
1386
1387         return result;
1388 }
1389
1390 int acpi_video_get_edid(struct acpi_device *device, int type, int device_id,
1391                         void **edid)
1392 {
1393         struct acpi_video_bus *video;
1394         struct acpi_video_device *video_device;
1395         union acpi_object *buffer = NULL;
1396         acpi_status status;
1397         int i, length;
1398
1399         if (!device || !acpi_driver_data(device))
1400                 return -EINVAL;
1401
1402         video = acpi_driver_data(device);
1403
1404         for (i = 0; i < video->attached_count; i++) {
1405                 video_device = video->attached_array[i].bind_info;
1406                 length = 256;
1407
1408                 if (!video_device)
1409                         continue;
1410
1411                 if (!video_device->cap._DDC)
1412                         continue;
1413
1414                 if (type) {
1415                         switch (type) {
1416                         case ACPI_VIDEO_DISPLAY_CRT:
1417                                 if (!video_device->flags.crt)
1418                                         continue;
1419                                 break;
1420                         case ACPI_VIDEO_DISPLAY_TV:
1421                                 if (!video_device->flags.tvout)
1422                                         continue;
1423                                 break;
1424                         case ACPI_VIDEO_DISPLAY_DVI:
1425                                 if (!video_device->flags.dvi)
1426                                         continue;
1427                                 break;
1428                         case ACPI_VIDEO_DISPLAY_LCD:
1429                                 if (!video_device->flags.lcd)
1430                                         continue;
1431                                 break;
1432                         }
1433                 } else if (video_device->device_id != device_id) {
1434                         continue;
1435                 }
1436
1437                 status = acpi_video_device_EDID(video_device, &buffer, length);
1438
1439                 if (ACPI_FAILURE(status) || !buffer ||
1440                     buffer->type != ACPI_TYPE_BUFFER) {
1441                         length = 128;
1442                         status = acpi_video_device_EDID(video_device, &buffer,
1443                                                         length);
1444                         if (ACPI_FAILURE(status) || !buffer ||
1445                             buffer->type != ACPI_TYPE_BUFFER) {
1446                                 continue;
1447                         }
1448                 }
1449
1450                 *edid = buffer->buffer.pointer;
1451                 return length;
1452         }
1453
1454         return -ENODEV;
1455 }
1456 EXPORT_SYMBOL(acpi_video_get_edid);
1457
1458 static int
1459 acpi_video_bus_get_devices(struct acpi_video_bus *video,
1460                            struct acpi_device *device)
1461 {
1462         int status = 0;
1463         struct acpi_device *dev;
1464
1465         /*
1466          * There are systems where video module known to work fine regardless
1467          * of broken _DOD and ignoring returned value here doesn't cause
1468          * any issues later.
1469          */
1470         acpi_video_device_enumerate(video);
1471
1472         list_for_each_entry(dev, &device->children, node) {
1473
1474                 status = acpi_video_bus_get_one_device(dev, video);
1475                 if (status) {
1476                         dev_err(&dev->dev, "Can't attach device\n");
1477                         break;
1478                 }
1479         }
1480         return status;
1481 }
1482
1483 static int acpi_video_bus_put_one_device(struct acpi_video_device *device)
1484 {
1485         acpi_status status;
1486
1487         if (!device || !device->video)
1488                 return -ENOENT;
1489
1490         if (device->flags.notify) {
1491                 status = acpi_remove_notify_handler(device->dev->handle,
1492                                 ACPI_DEVICE_NOTIFY, acpi_video_device_notify);
1493                 if (ACPI_FAILURE(status))
1494                         dev_err(&device->dev->dev,
1495                                         "Can't remove video notify handler\n");
1496         }
1497
1498         if (device->backlight) {
1499                 backlight_device_unregister(device->backlight);
1500                 device->backlight = NULL;
1501         }
1502         if (device->cooling_dev) {
1503                 sysfs_remove_link(&device->dev->dev.kobj,
1504                                   "thermal_cooling");
1505                 sysfs_remove_link(&device->cooling_dev->device.kobj,
1506                                   "device");
1507                 thermal_cooling_device_unregister(device->cooling_dev);
1508                 device->cooling_dev = NULL;
1509         }
1510
1511         return 0;
1512 }
1513
1514 static int acpi_video_bus_put_devices(struct acpi_video_bus *video)
1515 {
1516         int status;
1517         struct acpi_video_device *dev, *next;
1518
1519         mutex_lock(&video->device_list_lock);
1520
1521         list_for_each_entry_safe(dev, next, &video->video_device_list, entry) {
1522
1523                 status = acpi_video_bus_put_one_device(dev);
1524                 if (ACPI_FAILURE(status))
1525                         printk(KERN_WARNING PREFIX
1526                                "hhuuhhuu bug in acpi video driver.\n");
1527
1528                 if (dev->brightness) {
1529                         kfree(dev->brightness->levels);
1530                         kfree(dev->brightness);
1531                 }
1532                 list_del(&dev->entry);
1533                 kfree(dev);
1534         }
1535
1536         mutex_unlock(&video->device_list_lock);
1537
1538         return 0;
1539 }
1540
1541 /* acpi_video interface */
1542
1543 static int acpi_video_bus_start_devices(struct acpi_video_bus *video)
1544 {
1545         return acpi_video_bus_DOS(video, 0, 0);
1546 }
1547
1548 static int acpi_video_bus_stop_devices(struct acpi_video_bus *video)
1549 {
1550         return acpi_video_bus_DOS(video, 0, 1);
1551 }
1552
1553 static void acpi_video_bus_notify(struct acpi_device *device, u32 event)
1554 {
1555         struct acpi_video_bus *video = acpi_driver_data(device);
1556         struct input_dev *input;
1557         int keycode = 0;
1558
1559         if (!video)
1560                 return;
1561
1562         input = video->input;
1563
1564         switch (event) {
1565         case ACPI_VIDEO_NOTIFY_SWITCH:  /* User requested a switch,
1566                                          * most likely via hotkey. */
1567                 acpi_bus_generate_proc_event(device, event, 0);
1568                 keycode = KEY_SWITCHVIDEOMODE;
1569                 break;
1570
1571         case ACPI_VIDEO_NOTIFY_PROBE:   /* User plugged in or removed a video
1572                                          * connector. */
1573                 acpi_video_device_enumerate(video);
1574                 acpi_video_device_rebind(video);
1575                 acpi_bus_generate_proc_event(device, event, 0);
1576                 keycode = KEY_SWITCHVIDEOMODE;
1577                 break;
1578
1579         case ACPI_VIDEO_NOTIFY_CYCLE:   /* Cycle Display output hotkey pressed. */
1580                 acpi_bus_generate_proc_event(device, event, 0);
1581                 keycode = KEY_SWITCHVIDEOMODE;
1582                 break;
1583         case ACPI_VIDEO_NOTIFY_NEXT_OUTPUT:     /* Next Display output hotkey pressed. */
1584                 acpi_bus_generate_proc_event(device, event, 0);
1585                 keycode = KEY_VIDEO_NEXT;
1586                 break;
1587         case ACPI_VIDEO_NOTIFY_PREV_OUTPUT:     /* previous Display output hotkey pressed. */
1588                 acpi_bus_generate_proc_event(device, event, 0);
1589                 keycode = KEY_VIDEO_PREV;
1590                 break;
1591
1592         default:
1593                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1594                                   "Unsupported event [0x%x]\n", event));
1595                 break;
1596         }
1597
1598         if (acpi_notifier_call_chain(device, event, 0))
1599                 /* Something vetoed the keypress. */
1600                 keycode = 0;
1601
1602         if (keycode) {
1603                 input_report_key(input, keycode, 1);
1604                 input_sync(input);
1605                 input_report_key(input, keycode, 0);
1606                 input_sync(input);
1607         }
1608
1609         return;
1610 }
1611
1612 static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data)
1613 {
1614         struct acpi_video_device *video_device = data;
1615         struct acpi_device *device = NULL;
1616         struct acpi_video_bus *bus;
1617         struct input_dev *input;
1618         int keycode = 0;
1619
1620         if (!video_device)
1621                 return;
1622
1623         device = video_device->dev;
1624         bus = video_device->video;
1625         input = bus->input;
1626
1627         switch (event) {
1628         case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:        /* Cycle brightness */
1629                 if (brightness_switch_enabled)
1630                         acpi_video_switch_brightness(video_device, event);
1631                 acpi_bus_generate_proc_event(device, event, 0);
1632                 keycode = KEY_BRIGHTNESS_CYCLE;
1633                 break;
1634         case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:  /* Increase brightness */
1635                 if (brightness_switch_enabled)
1636                         acpi_video_switch_brightness(video_device, event);
1637                 acpi_bus_generate_proc_event(device, event, 0);
1638                 keycode = KEY_BRIGHTNESSUP;
1639                 break;
1640         case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:  /* Decrease brightness */
1641                 if (brightness_switch_enabled)
1642                         acpi_video_switch_brightness(video_device, event);
1643                 acpi_bus_generate_proc_event(device, event, 0);
1644                 keycode = KEY_BRIGHTNESSDOWN;
1645                 break;
1646         case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS: /* zero brightness */
1647                 if (brightness_switch_enabled)
1648                         acpi_video_switch_brightness(video_device, event);
1649                 acpi_bus_generate_proc_event(device, event, 0);
1650                 keycode = KEY_BRIGHTNESS_ZERO;
1651                 break;
1652         case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:     /* display device off */
1653                 if (brightness_switch_enabled)
1654                         acpi_video_switch_brightness(video_device, event);
1655                 acpi_bus_generate_proc_event(device, event, 0);
1656                 keycode = KEY_DISPLAY_OFF;
1657                 break;
1658         default:
1659                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1660                                   "Unsupported event [0x%x]\n", event));
1661                 break;
1662         }
1663
1664         acpi_notifier_call_chain(device, event, 0);
1665
1666         if (keycode) {
1667                 input_report_key(input, keycode, 1);
1668                 input_sync(input);
1669                 input_report_key(input, keycode, 0);
1670                 input_sync(input);
1671         }
1672
1673         return;
1674 }
1675
1676 static int acpi_video_resume(struct notifier_block *nb,
1677                                 unsigned long val, void *ign)
1678 {
1679         struct acpi_video_bus *video;
1680         struct acpi_video_device *video_device;
1681         int i;
1682
1683         switch (val) {
1684         case PM_HIBERNATION_PREPARE:
1685         case PM_SUSPEND_PREPARE:
1686         case PM_RESTORE_PREPARE:
1687                 return NOTIFY_DONE;
1688         }
1689
1690         video = container_of(nb, struct acpi_video_bus, pm_nb);
1691
1692         dev_info(&video->device->dev, "Restoring backlight state\n");
1693
1694         for (i = 0; i < video->attached_count; i++) {
1695                 video_device = video->attached_array[i].bind_info;
1696                 if (video_device && video_device->backlight)
1697                         acpi_video_set_brightness(video_device->backlight);
1698         }
1699
1700         return NOTIFY_OK;
1701 }
1702
1703 static acpi_status
1704 acpi_video_bus_match(acpi_handle handle, u32 level, void *context,
1705                         void **return_value)
1706 {
1707         struct acpi_device *device = context;
1708         struct acpi_device *sibling;
1709         int result;
1710
1711         if (handle == device->handle)
1712                 return AE_CTRL_TERMINATE;
1713
1714         result = acpi_bus_get_device(handle, &sibling);
1715         if (result)
1716                 return AE_OK;
1717
1718         if (!strcmp(acpi_device_name(sibling), ACPI_VIDEO_BUS_NAME))
1719                         return AE_ALREADY_EXISTS;
1720
1721         return AE_OK;
1722 }
1723
1724 static int instance;
1725
1726 static int acpi_video_bus_add(struct acpi_device *device)
1727 {
1728         struct acpi_video_bus *video;
1729         struct input_dev *input;
1730         int error;
1731         acpi_status status;
1732
1733         status = acpi_walk_namespace(ACPI_TYPE_DEVICE,
1734                                 device->parent->handle, 1,
1735                                 acpi_video_bus_match, NULL,
1736                                 device, NULL);
1737         if (status == AE_ALREADY_EXISTS) {
1738                 printk(KERN_WARNING FW_BUG
1739                         "Duplicate ACPI video bus devices for the"
1740                         " same VGA controller, please try module "
1741                         "parameter \"video.allow_duplicates=1\""
1742                         "if the current driver doesn't work.\n");
1743                 if (!allow_duplicates)
1744                         return -ENODEV;
1745         }
1746
1747         video = kzalloc(sizeof(struct acpi_video_bus), GFP_KERNEL);
1748         if (!video)
1749                 return -ENOMEM;
1750
1751         /* a hack to fix the duplicate name "VID" problem on T61 */
1752         if (!strcmp(device->pnp.bus_id, "VID")) {
1753                 if (instance)
1754                         device->pnp.bus_id[3] = '0' + instance;
1755                 instance ++;
1756         }
1757         /* a hack to fix the duplicate name "VGA" problem on Pa 3553 */
1758         if (!strcmp(device->pnp.bus_id, "VGA")) {
1759                 if (instance)
1760                         device->pnp.bus_id[3] = '0' + instance;
1761                 instance++;
1762         }
1763
1764         video->device = device;
1765         strcpy(acpi_device_name(device), ACPI_VIDEO_BUS_NAME);
1766         strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
1767         device->driver_data = video;
1768
1769         acpi_video_bus_find_cap(video);
1770         error = acpi_video_bus_check(video);
1771         if (error)
1772                 goto err_free_video;
1773
1774         mutex_init(&video->device_list_lock);
1775         INIT_LIST_HEAD(&video->video_device_list);
1776
1777         error = acpi_video_bus_get_devices(video, device);
1778         if (error)
1779                 goto err_put_video;
1780
1781         video->input = input = input_allocate_device();
1782         if (!input) {
1783                 error = -ENOMEM;
1784                 goto err_put_video;
1785         }
1786
1787         error = acpi_video_bus_start_devices(video);
1788         if (error)
1789                 goto err_free_input_dev;
1790
1791         snprintf(video->phys, sizeof(video->phys),
1792                 "%s/video/input0", acpi_device_hid(video->device));
1793
1794         input->name = acpi_device_name(video->device);
1795         input->phys = video->phys;
1796         input->id.bustype = BUS_HOST;
1797         input->id.product = 0x06;
1798         input->dev.parent = &device->dev;
1799         input->evbit[0] = BIT(EV_KEY);
1800         set_bit(KEY_SWITCHVIDEOMODE, input->keybit);
1801         set_bit(KEY_VIDEO_NEXT, input->keybit);
1802         set_bit(KEY_VIDEO_PREV, input->keybit);
1803         set_bit(KEY_BRIGHTNESS_CYCLE, input->keybit);
1804         set_bit(KEY_BRIGHTNESSUP, input->keybit);
1805         set_bit(KEY_BRIGHTNESSDOWN, input->keybit);
1806         set_bit(KEY_BRIGHTNESS_ZERO, input->keybit);
1807         set_bit(KEY_DISPLAY_OFF, input->keybit);
1808
1809         printk(KERN_INFO PREFIX "%s [%s] (multi-head: %s  rom: %s  post: %s)\n",
1810                ACPI_VIDEO_DEVICE_NAME, acpi_device_bid(device),
1811                video->flags.multihead ? "yes" : "no",
1812                video->flags.rom ? "yes" : "no",
1813                video->flags.post ? "yes" : "no");
1814
1815         video->pm_nb.notifier_call = acpi_video_resume;
1816         video->pm_nb.priority = 0;
1817         error = register_pm_notifier(&video->pm_nb);
1818         if (error)
1819                 goto err_stop_video;
1820
1821         error = input_register_device(input);
1822         if (error)
1823                 goto err_unregister_pm_notifier;
1824
1825         return 0;
1826
1827  err_unregister_pm_notifier:
1828         unregister_pm_notifier(&video->pm_nb);
1829  err_stop_video:
1830         acpi_video_bus_stop_devices(video);
1831  err_free_input_dev:
1832         input_free_device(input);
1833  err_put_video:
1834         acpi_video_bus_put_devices(video);
1835         kfree(video->attached_array);
1836  err_free_video:
1837         kfree(video);
1838         device->driver_data = NULL;
1839
1840         return error;
1841 }
1842
1843 static int acpi_video_bus_remove(struct acpi_device *device)
1844 {
1845         struct acpi_video_bus *video = NULL;
1846
1847
1848         if (!device || !acpi_driver_data(device))
1849                 return -EINVAL;
1850
1851         video = acpi_driver_data(device);
1852
1853         unregister_pm_notifier(&video->pm_nb);
1854
1855         acpi_video_bus_stop_devices(video);
1856         acpi_video_bus_put_devices(video);
1857
1858         input_unregister_device(video->input);
1859         kfree(video->attached_array);
1860         kfree(video);
1861
1862         return 0;
1863 }
1864
1865 static int __init is_i740(struct pci_dev *dev)
1866 {
1867         if (dev->device == 0x00D1)
1868                 return 1;
1869         if (dev->device == 0x7000)
1870                 return 1;
1871         return 0;
1872 }
1873
1874 static int __init intel_opregion_present(void)
1875 {
1876         int opregion = 0;
1877         struct pci_dev *dev = NULL;
1878         u32 address;
1879
1880         for_each_pci_dev(dev) {
1881                 if ((dev->class >> 8) != PCI_CLASS_DISPLAY_VGA)
1882                         continue;
1883                 if (dev->vendor != PCI_VENDOR_ID_INTEL)
1884                         continue;
1885                 /* We don't want to poke around undefined i740 registers */
1886                 if (is_i740(dev))
1887                         continue;
1888                 pci_read_config_dword(dev, 0xfc, &address);
1889                 if (!address)
1890                         continue;
1891                 opregion = 1;
1892         }
1893         return opregion;
1894 }
1895
1896 int acpi_video_register(void)
1897 {
1898         int result = 0;
1899         if (register_count) {
1900                 /*
1901                  * if the function of acpi_video_register is already called,
1902                  * don't register the acpi_vide_bus again and return no error.
1903                  */
1904                 return 0;
1905         }
1906
1907         result = acpi_bus_register_driver(&acpi_video_bus);
1908         if (result < 0)
1909                 return -ENODEV;
1910
1911         /*
1912          * When the acpi_video_bus is loaded successfully, increase
1913          * the counter reference.
1914          */
1915         register_count = 1;
1916
1917         return 0;
1918 }
1919 EXPORT_SYMBOL(acpi_video_register);
1920
1921 void acpi_video_unregister(void)
1922 {
1923         if (!register_count) {
1924                 /*
1925                  * If the acpi video bus is already unloaded, don't
1926                  * unload it again and return directly.
1927                  */
1928                 return;
1929         }
1930         acpi_bus_unregister_driver(&acpi_video_bus);
1931
1932         register_count = 0;
1933
1934         return;
1935 }
1936 EXPORT_SYMBOL(acpi_video_unregister);
1937
1938 /*
1939  * This is kind of nasty. Hardware using Intel chipsets may require
1940  * the video opregion code to be run first in order to initialise
1941  * state before any ACPI video calls are made. To handle this we defer
1942  * registration of the video class until the opregion code has run.
1943  */
1944
1945 static int __init acpi_video_init(void)
1946 {
1947         dmi_check_system(video_dmi_table);
1948
1949         if (intel_opregion_present())
1950                 return 0;
1951
1952         return acpi_video_register();
1953 }
1954
1955 static void __exit acpi_video_exit(void)
1956 {
1957         acpi_video_unregister();
1958
1959         return;
1960 }
1961
1962 module_init(acpi_video_init);
1963 module_exit(acpi_video_exit);