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