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 int video_ignore_initial_backlight(const struct dmi_system_id *d)
 393 {
 394         use_bios_initial_backlight = 0;
 395         return 0;
 396 }
 397
 398 static struct dmi_system_id video_dmi_table[] __initdata = {
 399         /*
 400          * Broken _BQC workaround http://bugzilla.kernel.org/show_bug.cgi?id=13121
 401          */
 402         {
 403          .callback = video_set_bqc_offset,
 404          .ident = "Acer Aspire 5720",
 405          .matches = {
 406                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
 407                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5720"),
 408                 },
 409         },
 410         {
 411          .callback = video_set_bqc_offset,
 412          .ident = "Acer Aspire 5710Z",
 413          .matches = {
 414                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
 415                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5710Z"),
 416                 },
 417         },
 418         {
 419          .callback = video_set_bqc_offset,
 420          .ident = "eMachines E510",
 421          .matches = {
 422                 DMI_MATCH(DMI_BOARD_VENDOR, "EMACHINES"),
 423                 DMI_MATCH(DMI_PRODUCT_NAME, "eMachines E510"),
 424                 },
 425         },
 426         {
 427          .callback = video_set_bqc_offset,
 428          .ident = "Acer Aspire 5315",
 429          .matches = {
 430                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
 431                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5315"),
 432                 },
 433         },
 434         {
 435          .callback = video_set_bqc_offset,
 436          .ident = "Acer Aspire 7720",
 437          .matches = {
 438                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
 439                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 7720"),
 440                 },
 441         },
 442         {
 443          .callback = video_ignore_initial_backlight,
 444          .ident = "HP Folio 13-2000",
 445          .matches = {
 446                 DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
 447                 DMI_MATCH(DMI_PRODUCT_NAME, "HP Folio 13 - 2000 Notebook PC"),
 448                 },
 449         },
 450         {}
 451 };
 452
 453 static int
 454 acpi_video_device_lcd_get_level_current(struct acpi_video_device *device,
 455                                         unsigned long long *level, int init)
 456 {
 457         acpi_status status = AE_OK;
 458         int i;
 459
 460         if (device->cap._BQC || device->cap._BCQ) {
 461                 char *buf = device->cap._BQC ? "_BQC" : "_BCQ";
 462
 463                 status = acpi_evaluate_integer(device->dev->handle, buf,
 464                                                 NULL, level);
 465                 if (ACPI_SUCCESS(status)) {
 466                         if (device->brightness->flags._BQC_use_index) {
 467                                 if (device->brightness->flags._BCL_reversed)
 468                                         *level = device->brightness->count
 469                                                                  - 3 - (*level);
 470                                 *level = device->brightness->levels[*level + 2];
 471
 472                         }
 473                         *level += bqc_offset_aml_bug_workaround;
 474                         for (i = 2; i < device->brightness->count; i++)
 475                                 if (device->brightness->levels[i] == *level) {
 476                                         device->brightness->curr = *level;
 477                                         return 0;
 478                         }
 479                         if (!init) {
 480                                 /*
 481                                  * BQC returned an invalid level.
 482                                  * Stop using it.
 483                                  */
 484                                 ACPI_WARNING((AE_INFO,
 485                                               "%s returned an invalid level",
 486                                               buf));
 487                                 device->cap._BQC = device->cap._BCQ = 0;
 488                         }
 489                 } else {
 490                         /* Fixme:
 491                          * should we return an error or ignore this failure?
 492                          * dev->brightness->curr is a cached value which stores
 493                          * the correct current backlight level in most cases.
 494                          * ACPI video backlight still works w/ buggy _BQC.
 495                          * http://bugzilla.kernel.org/show_bug.cgi?id=12233
 496                          */
 497                         ACPI_WARNING((AE_INFO, "Evaluating %s failed", buf));
 498                         device->cap._BQC = device->cap._BCQ = 0;
 499                 }
 500         }
 501
 502         *level = device->brightness->curr;
 503         return 0;
 504 }
 505
 506 static int
 507 acpi_video_device_EDID(struct acpi_video_device *device,
 508                        union acpi_object **edid, ssize_t length)
 509 {
 510         int status;
 511         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 512         union acpi_object *obj;
 513         union acpi_object arg0 = { ACPI_TYPE_INTEGER };
 514         struct acpi_object_list args = { 1, &arg0 };
 515
 516
 517         *edid = NULL;
 518
 519         if (!device)
 520                 return -ENODEV;
 521         if (length == 128)
 522                 arg0.integer.value = 1;
 523         else if (length == 256)
 524                 arg0.integer.value = 2;
 525         else
 526                 return -EINVAL;
 527
 528         status = acpi_evaluate_object(device->dev->handle, "_DDC", &args, &buffer);
 529         if (ACPI_FAILURE(status))
 530                 return -ENODEV;
 531
 532         obj = buffer.pointer;
 533
 534         if (obj && obj->type == ACPI_TYPE_BUFFER)
 535                 *edid = obj;
 536         else {
 537                 printk(KERN_ERR PREFIX "Invalid _DDC data\n");
 538                 status = -EFAULT;
 539                 kfree(obj);
 540         }
 541
 542         return status;
 543 }
 544
 545 /* bus */
 546
 547 /*
 548  *  Arg:
 549  *      video           : video bus device pointer
 550  *      bios_flag       :
 551  *              0.      The system BIOS should NOT automatically switch(toggle)
 552  *                      the active display output.
 553  *              1.      The system BIOS should automatically switch (toggle) the
 554  *                      active display output. No switch event.
 555  *              2.      The _DGS value should be locked.
 556  *              3.      The system BIOS should not automatically switch (toggle) the
 557  *                      active display output, but instead generate the display switch
 558  *                      event notify code.
 559  *      lcd_flag        :
 560  *              0.      The system BIOS should automatically control the brightness level
 561  *                      of the LCD when the power changes from AC to DC
 562  *              1.      The system BIOS should NOT automatically control the brightness
 563  *                      level of the LCD when the power changes from AC to DC.
 564  * Return Value:
 565  *              -EINVAL wrong arg.
 566  */
 567
 568 static int
 569 acpi_video_bus_DOS(struct acpi_video_bus *video, int bios_flag, int lcd_flag)
 570 {
 571         acpi_status status;
 572         union acpi_object arg0 = { ACPI_TYPE_INTEGER };
 573         struct acpi_object_list args = { 1, &arg0 };
 574
 575         if (!video->cap._DOS)
 576                 return 0;
 577
 578         if (bios_flag < 0 || bios_flag > 3 || lcd_flag < 0 || lcd_flag > 1)
 579                 return -EINVAL;
 580         arg0.integer.value = (lcd_flag << 2) | bios_flag;
 581         video->dos_setting = arg0.integer.value;
 582         status = acpi_evaluate_object(video->device->handle, "_DOS",
 583                 &args, NULL);
 584         if (ACPI_FAILURE(status))
 585                 return -EIO;
 586
 587         return 0;
 588 }
 589
 590 /*
 591  * Simple comparison function used to sort backlight levels.
 592  */
 593
 594 static int
 595 acpi_video_cmp_level(const void *a, const void *b)
 596 {
 597         return *(int *)a - *(int *)b;
 598 }
 599
 600 /*
 601  *  Arg:
 602  *      device  : video output device (LCD, CRT, ..)
 603  *
 604  *  Return Value:
 605  *      Maximum brightness level
 606  *
 607  *  Allocate and initialize device->brightness.
 608  */
 609
 610 static int
 611 acpi_video_init_brightness(struct acpi_video_device *device)
 612 {
 613         union acpi_object *obj = NULL;
 614         int i, max_level = 0, count = 0, level_ac_battery = 0;
 615         unsigned long long level, level_old;
 616         union acpi_object *o;
 617         struct acpi_video_device_brightness *br = NULL;
 618         int result = -EINVAL;
 619
 620         if (!ACPI_SUCCESS(acpi_video_device_lcd_query_levels(device, &obj))) {
 621                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Could not query available "
 622                                                 "LCD brightness level\n"));
 623                 goto out;
 624         }
 625
 626         if (obj->package.count < 2)
 627                 goto out;
 628
 629         br = kzalloc(sizeof(*br), GFP_KERNEL);
 630         if (!br) {
 631                 printk(KERN_ERR "can't allocate memory\n");
 632                 result = -ENOMEM;
 633                 goto out;
 634         }
 635
 636         br->levels = kmalloc((obj->package.count + 2) * sizeof *(br->levels),
 637                                 GFP_KERNEL);
 638         if (!br->levels) {
 639                 result = -ENOMEM;
 640                 goto out_free;
 641         }
 642
 643         for (i = 0; i < obj->package.count; i++) {
 644                 o = (union acpi_object *)&obj->package.elements[i];
 645                 if (o->type != ACPI_TYPE_INTEGER) {
 646                         printk(KERN_ERR PREFIX "Invalid data\n");
 647                         continue;
 648                 }
 649                 br->levels[count] = (u32) o->integer.value;
 650
 651                 if (br->levels[count] > max_level)
 652                         max_level = br->levels[count];
 653                 count++;
 654         }
 655
 656         /*
 657          * some buggy BIOS don't export the levels
 658          * when machine is on AC/Battery in _BCL package.
 659          * In this case, the first two elements in _BCL packages
 660          * are also supported brightness levels that OS should take care of.
 661          */
 662         for (i = 2; i < count; i++) {
 663                 if (br->levels[i] == br->levels[0])
 664                         level_ac_battery++;
 665                 if (br->levels[i] == br->levels[1])
 666                         level_ac_battery++;
 667         }
 668
 669         if (level_ac_battery < 2) {
 670                 level_ac_battery = 2 - level_ac_battery;
 671                 br->flags._BCL_no_ac_battery_levels = 1;
 672                 for (i = (count - 1 + level_ac_battery); i >= 2; i--)
 673                         br->levels[i] = br->levels[i - level_ac_battery];
 674                 count += level_ac_battery;
 675         } else if (level_ac_battery > 2)
 676                 ACPI_ERROR((AE_INFO, "Too many duplicates in _BCL package\n"));
 677
 678         /* Check if the _BCL package is in a reversed order */
 679         if (max_level == br->levels[2]) {
 680                 br->flags._BCL_reversed = 1;
 681                 sort(&br->levels[2], count - 2, sizeof(br->levels[2]),
 682                         acpi_video_cmp_level, NULL);
 683         } else if (max_level != br->levels[count - 1])
 684                 ACPI_ERROR((AE_INFO,
 685                             "Found unordered _BCL package\n"));
 686
 687         br->count = count;
 688         device->brightness = br;
 689
 690         /* Check the input/output of _BQC/_BCL/_BCM */
 691         if ((max_level < 100) && (max_level <= (count - 2)))
 692                 br->flags._BCL_use_index = 1;
 693
 694         /*
 695          * _BCM is always consistent with _BCL,
 696          * at least for all the laptops we have ever seen.
 697          */
 698         br->flags._BCM_use_index = br->flags._BCL_use_index;
 699
 700         /* _BQC uses INDEX while _BCL uses VALUE in some laptops */
 701         br->curr = level = max_level;
 702
 703         if (!device->cap._BQC)
 704                 goto set_level;
 705
 706         result = acpi_video_device_lcd_get_level_current(device, &level_old, 1);
 707         if (result)
 708                 goto out_free_levels;
 709
 710         /*
 711          * Set the level to maximum and check if _BQC uses indexed value
 712          */
 713         result = acpi_video_device_lcd_set_level(device, max_level);
 714         if (result)
 715                 goto out_free_levels;
 716
 717         result = acpi_video_device_lcd_get_level_current(device, &level, 0);
 718         if (result)
 719                 goto out_free_levels;
 720
 721         br->flags._BQC_use_index = (level == max_level ? 0 : 1);
 722
 723         if (!br->flags._BQC_use_index) {
 724                 /*
 725                  * Set the backlight to the initial state.
 726                  * On some buggy laptops, _BQC returns an uninitialized value
 727                  * when invoked for the first time, i.e. level_old is invalid.
 728                  * set the backlight to max_level in this case
 729                  */
 730                 if (use_bios_initial_backlight) {
 731                         for (i = 2; i < br->count; i++)
 732                                 if (level_old == br->levels[i])
 733                                         level = level_old;
 734                 }
 735                 goto set_level;
 736         }
 737
 738         if (br->flags._BCL_reversed)
 739                 level_old = (br->count - 1) - level_old;
 740         level = br->levels[level_old];
 741
 742 set_level:
 743         result = acpi_video_device_lcd_set_level(device, level);
 744         if (result)
 745                 goto out_free_levels;
 746
 747         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 748                           "found %d brightness levels\n", count - 2));
 749         kfree(obj);
 750         return result;
 751
 752 out_free_levels:
 753         kfree(br->levels);
 754 out_free:
 755         kfree(br);
 756 out:
 757         device->brightness = NULL;
 758         kfree(obj);
 759         return result;
 760 }
 761
 762 /*
 763  *  Arg:
 764  *      device  : video output device (LCD, CRT, ..)
 765  *
 766  *  Return Value:
 767  *      None
 768  *
 769  *  Find out all required AML methods defined under the output
 770  *  device.
 771  */
 772
 773 static void acpi_video_device_find_cap(struct acpi_video_device *device)
 774 {
 775         acpi_handle h_dummy1;
 776
 777         if (ACPI_SUCCESS(acpi_get_handle(device->dev->handle, "_ADR", &h_dummy1))) {
 778                 device->cap._ADR = 1;
 779         }
 780         if (ACPI_SUCCESS(acpi_get_handle(device->dev->handle, "_BCL", &h_dummy1))) {
 781                 device->cap._BCL = 1;
 782         }
 783         if (ACPI_SUCCESS(acpi_get_handle(device->dev->handle, "_BCM", &h_dummy1))) {
 784                 device->cap._BCM = 1;
 785         }
 786         if (ACPI_SUCCESS(acpi_get_handle(device->dev->handle,"_BQC",&h_dummy1)))
 787                 device->cap._BQC = 1;
 788         else if (ACPI_SUCCESS(acpi_get_handle(device->dev->handle, "_BCQ",
 789                                 &h_dummy1))) {
 790                 printk(KERN_WARNING FW_BUG "_BCQ is used instead of _BQC\n");
 791                 device->cap._BCQ = 1;
 792         }
 793
 794         if (ACPI_SUCCESS(acpi_get_handle(device->dev->handle, "_DDC", &h_dummy1))) {
 795                 device->cap._DDC = 1;
 796         }
 797
 798         if (acpi_video_backlight_support()) {
 799                 struct backlight_properties props;
 800                 struct pci_dev *pdev;
 801                 acpi_handle acpi_parent;
 802                 struct device *parent = NULL;
 803                 int result;
 804                 static int count = 0;
 805                 char *name;
 806
 807                 result = acpi_video_init_brightness(device);
 808                 if (result)
 809                         return;
 810                 name = kasprintf(GFP_KERNEL, "acpi_video%d", count);
 811                 if (!name)
 812                         return;
 813                 count++;
 814
 815                 acpi_get_parent(device->dev->handle, &acpi_parent);
 816
 817                 pdev = acpi_get_pci_dev(acpi_parent);
 818                 if (pdev) {
 819                         parent = &pdev->dev;
 820                         pci_dev_put(pdev);
 821                 }
 822
 823                 memset(&props, 0, sizeof(struct backlight_properties));
 824                 props.type = BACKLIGHT_FIRMWARE;
 825                 props.max_brightness = device->brightness->count - 3;
 826                 device->backlight = backlight_device_register(name,
 827                                                               parent,
 828                                                               device,
 829                                                               &acpi_backlight_ops,
 830                                                               &props);
 831                 kfree(name);
 832                 if (IS_ERR(device->backlight))
 833                         return;
 834
 835                 /*
 836                  * Save current brightness level in case we have to restore it
 837                  * before acpi_video_device_lcd_set_level() is called next time.
 838                  */
 839                 device->backlight->props.brightness =
 840                                 acpi_video_get_brightness(device->backlight);
 841
 842                 device->cooling_dev = thermal_cooling_device_register("LCD",
 843                                         device->dev, &video_cooling_ops);
 844                 if (IS_ERR(device->cooling_dev)) {
 845                         /*
 846                          * Set cooling_dev to NULL so we don't crash trying to
 847                          * free it.
 848                          * Also, why the hell we are returning early and
 849                          * not attempt to register video output if cooling
 850                          * device registration failed?
 851                          * -- dtor
 852                          */
 853                         device->cooling_dev = NULL;
 854                         return;
 855                 }
 856
 857                 dev_info(&device->dev->dev, "registered as cooling_device%d\n",
 858                          device->cooling_dev->id);
 859                 result = sysfs_create_link(&device->dev->dev.kobj,
 860                                 &device->cooling_dev->device.kobj,
 861                                 "thermal_cooling");
 862                 if (result)
 863                         printk(KERN_ERR PREFIX "Create sysfs link\n");
 864                 result = sysfs_create_link(&device->cooling_dev->device.kobj,
 865                                 &device->dev->dev.kobj, "device");
 866                 if (result)
 867                         printk(KERN_ERR PREFIX "Create sysfs link\n");
 868
 869         }
 870 }
 871
 872 /*
 873  *  Arg:
 874  *      device  : video output device (VGA)
 875  *
 876  *  Return Value:
 877  *      None
 878  *
 879  *  Find out all required AML methods defined under the video bus device.
 880  */
 881
 882 static void acpi_video_bus_find_cap(struct acpi_video_bus *video)
 883 {
 884         acpi_handle h_dummy1;
 885
 886         if (ACPI_SUCCESS(acpi_get_handle(video->device->handle, "_DOS", &h_dummy1))) {
 887                 video->cap._DOS = 1;
 888         }
 889         if (ACPI_SUCCESS(acpi_get_handle(video->device->handle, "_DOD", &h_dummy1))) {
 890                 video->cap._DOD = 1;
 891         }
 892         if (ACPI_SUCCESS(acpi_get_handle(video->device->handle, "_ROM", &h_dummy1))) {
 893                 video->cap._ROM = 1;
 894         }
 895         if (ACPI_SUCCESS(acpi_get_handle(video->device->handle, "_GPD", &h_dummy1))) {
 896                 video->cap._GPD = 1;
 897         }
 898         if (ACPI_SUCCESS(acpi_get_handle(video->device->handle, "_SPD", &h_dummy1))) {
 899                 video->cap._SPD = 1;
 900         }
 901         if (ACPI_SUCCESS(acpi_get_handle(video->device->handle, "_VPO", &h_dummy1))) {
 902                 video->cap._VPO = 1;
 903         }
 904 }
 905
 906 /*
 907  * Check whether the video bus device has required AML method to
 908  * support the desired features
 909  */
 910
 911 static int acpi_video_bus_check(struct acpi_video_bus *video)
 912 {
 913         acpi_status status = -ENOENT;
 914         struct pci_dev *dev;
 915
 916         if (!video)
 917                 return -EINVAL;
 918
 919         dev = acpi_get_pci_dev(video->device->handle);
 920         if (!dev)
 921                 return -ENODEV;
 922         pci_dev_put(dev);
 923
 924         /* Since there is no HID, CID and so on for VGA driver, we have
 925          * to check well known required nodes.
 926          */
 927
 928         /* Does this device support video switching? */
 929         if (video->cap._DOS || video->cap._DOD) {
 930                 if (!video->cap._DOS) {
 931                         printk(KERN_WARNING FW_BUG
 932                                 "ACPI(%s) defines _DOD but not _DOS\n",
 933                                 acpi_device_bid(video->device));
 934                 }
 935                 video->flags.multihead = 1;
 936                 status = 0;
 937         }
 938
 939         /* Does this device support retrieving a video ROM? */
 940         if (video->cap._ROM) {
 941                 video->flags.rom = 1;
 942                 status = 0;
 943         }
 944
 945         /* Does this device support configuring which video device to POST? */
 946         if (video->cap._GPD && video->cap._SPD && video->cap._VPO) {
 947                 video->flags.post = 1;
 948                 status = 0;
 949         }
 950
 951         return status;
 952 }
 953
 954 /* --------------------------------------------------------------------------
 955                                  Driver Interface
 956    -------------------------------------------------------------------------- */
 957
 958 /* device interface */
 959 static struct acpi_video_device_attrib*
 960 acpi_video_get_device_attr(struct acpi_video_bus *video, unsigned long device_id)
 961 {
 962         struct acpi_video_enumerated_device *ids;
 963         int i;
 964
 965         for (i = 0; i < video->attached_count; i++) {
 966                 ids = &video->attached_array[i];
 967                 if ((ids->value.int_val & 0xffff) == device_id)
 968                         return &ids->value.attrib;
 969         }
 970
 971         return NULL;
 972 }
 973
 974 static int
 975 acpi_video_get_device_type(struct acpi_video_bus *video,
 976                            unsigned long device_id)
 977 {
 978         struct acpi_video_enumerated_device *ids;
 979         int i;
 980
 981         for (i = 0; i < video->attached_count; i++) {
 982                 ids = &video->attached_array[i];
 983                 if ((ids->value.int_val & 0xffff) == device_id)
 984                         return ids->value.int_val;
 985         }
 986
 987         return 0;
 988 }
 989
 990 static int
 991 acpi_video_bus_get_one_device(struct acpi_device *device,
 992                               struct acpi_video_bus *video)
 993 {
 994         unsigned long long device_id;
 995         int status, device_type;
 996         struct acpi_video_device *data;
 997         struct acpi_video_device_attrib* attribute;
 998
 999         if (!device || !video)
1000                 return -EINVAL;
1001
1002         status =
1003             acpi_evaluate_integer(device->handle, "_ADR", NULL, &device_id);
1004         if (ACPI_SUCCESS(status)) {
1005
1006                 data = kzalloc(sizeof(struct acpi_video_device), GFP_KERNEL);
1007                 if (!data)
1008                         return -ENOMEM;
1009
1010                 strcpy(acpi_device_name(device), ACPI_VIDEO_DEVICE_NAME);
1011                 strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
1012                 device->driver_data = data;
1013
1014                 data->device_id = device_id;
1015                 data->video = video;
1016                 data->dev = device;
1017
1018                 attribute = acpi_video_get_device_attr(video, device_id);
1019
1020                 if((attribute != NULL) && attribute->device_id_scheme) {
1021                         switch (attribute->display_type) {
1022                         case ACPI_VIDEO_DISPLAY_CRT:
1023                                 data->flags.crt = 1;
1024                                 break;
1025                         case ACPI_VIDEO_DISPLAY_TV:
1026                                 data->flags.tvout = 1;
1027                                 break;
1028                         case ACPI_VIDEO_DISPLAY_DVI:
1029                                 data->flags.dvi = 1;
1030                                 break;
1031                         case ACPI_VIDEO_DISPLAY_LCD:
1032                                 data->flags.lcd = 1;
1033                                 break;
1034                         default:
1035                                 data->flags.unknown = 1;
1036                                 break;
1037                         }
1038                         if(attribute->bios_can_detect)
1039                                 data->flags.bios = 1;
1040                 } else {
1041                         /* Check for legacy IDs */
1042                         device_type = acpi_video_get_device_type(video,
1043                                                                  device_id);
1044                         /* Ignore bits 16 and 18-20 */
1045                         switch (device_type & 0xffe2ffff) {
1046                         case ACPI_VIDEO_DISPLAY_LEGACY_MONITOR:
1047                                 data->flags.crt = 1;
1048                                 break;
1049                         case ACPI_VIDEO_DISPLAY_LEGACY_PANEL:
1050                                 data->flags.lcd = 1;
1051                                 break;
1052                         case ACPI_VIDEO_DISPLAY_LEGACY_TV:
1053                                 data->flags.tvout = 1;
1054                                 break;
1055                         default:
1056                                 data->flags.unknown = 1;
1057                         }
1058                 }
1059
1060                 acpi_video_device_bind(video, data);
1061                 acpi_video_device_find_cap(data);
1062
1063                 status = acpi_install_notify_handler(device->handle,
1064                                                      ACPI_DEVICE_NOTIFY,
1065                                                      acpi_video_device_notify,
1066                                                      data);
1067                 if (ACPI_FAILURE(status)) {
1068                         printk(KERN_ERR PREFIX
1069                                           "Error installing notify handler\n");
1070                         if(data->brightness)
1071                                 kfree(data->brightness->levels);
1072                         kfree(data->brightness);
1073                         kfree(data);
1074                         return -ENODEV;
1075                 }
1076
1077                 mutex_lock(&video->device_list_lock);
1078                 list_add_tail(&data->entry, &video->video_device_list);
1079                 mutex_unlock(&video->device_list_lock);
1080
1081                 return 0;
1082         }
1083
1084         return -ENOENT;
1085 }
1086
1087 /*
1088  *  Arg:
1089  *      video   : video bus device
1090  *
1091  *  Return:
1092  *      none
1093  *
1094  *  Enumerate the video device list of the video bus,
1095  *  bind the ids with the corresponding video devices
1096  *  under the video bus.
1097  */
1098
1099 static void acpi_video_device_rebind(struct acpi_video_bus *video)
1100 {
1101         struct acpi_video_device *dev;
1102
1103         mutex_lock(&video->device_list_lock);
1104
1105         list_for_each_entry(dev, &video->video_device_list, entry)
1106                 acpi_video_device_bind(video, dev);
1107
1108         mutex_unlock(&video->device_list_lock);
1109 }
1110
1111 /*
1112  *  Arg:
1113  *      video   : video bus device
1114  *      device  : video output device under the video
1115  *              bus
1116  *
1117  *  Return:
1118  *      none
1119  *
1120  *  Bind the ids with the corresponding video devices
1121  *  under the video bus.
1122  */
1123
1124 static void
1125 acpi_video_device_bind(struct acpi_video_bus *video,
1126                        struct acpi_video_device *device)
1127 {
1128         struct acpi_video_enumerated_device *ids;
1129         int i;
1130
1131         for (i = 0; i < video->attached_count; i++) {
1132                 ids = &video->attached_array[i];
1133                 if (device->device_id == (ids->value.int_val & 0xffff)) {
1134                         ids->bind_info = device;
1135                         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "device_bind %d\n", i));
1136                 }
1137         }
1138 }
1139
1140 /*
1141  *  Arg:
1142  *      video   : video bus device
1143  *
1144  *  Return:
1145  *      < 0     : error
1146  *
1147  *  Call _DOD to enumerate all devices attached to display adapter
1148  *
1149  */
1150
1151 static int acpi_video_device_enumerate(struct acpi_video_bus *video)
1152 {
1153         int status;
1154         int count;
1155         int i;
1156         struct acpi_video_enumerated_device *active_list;
1157         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1158         union acpi_object *dod = NULL;
1159         union acpi_object *obj;
1160
1161         status = acpi_evaluate_object(video->device->handle, "_DOD", NULL, &buffer);
1162         if (!ACPI_SUCCESS(status)) {
1163                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _DOD"));
1164                 return status;
1165         }
1166
1167         dod = buffer.pointer;
1168         if (!dod || (dod->type != ACPI_TYPE_PACKAGE)) {
1169                 ACPI_EXCEPTION((AE_INFO, status, "Invalid _DOD data"));
1170                 status = -EFAULT;
1171                 goto out;
1172         }
1173
1174         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d video heads in _DOD\n",
1175                           dod->package.count));
1176
1177         active_list = kcalloc(1 + dod->package.count,
1178                               sizeof(struct acpi_video_enumerated_device),
1179                               GFP_KERNEL);
1180         if (!active_list) {
1181                 status = -ENOMEM;
1182                 goto out;
1183         }
1184
1185         count = 0;
1186         for (i = 0; i < dod->package.count; i++) {
1187                 obj = &dod->package.elements[i];
1188
1189                 if (obj->type != ACPI_TYPE_INTEGER) {
1190                         printk(KERN_ERR PREFIX
1191                                 "Invalid _DOD data in element %d\n", i);
1192                         continue;
1193                 }
1194
1195                 active_list[count].value.int_val = obj->integer.value;
1196                 active_list[count].bind_info = NULL;
1197                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "dod element[%d] = %d\n", i,
1198                                   (int)obj->integer.value));
1199                 count++;
1200         }
1201
1202         kfree(video->attached_array);
1203
1204         video->attached_array = active_list;
1205         video->attached_count = count;
1206
1207  out:
1208         kfree(buffer.pointer);
1209         return status;
1210 }
1211
1212 static int
1213 acpi_video_get_next_level(struct acpi_video_device *device,
1214                           u32 level_current, u32 event)
1215 {
1216         int min, max, min_above, max_below, i, l, delta = 255;
1217         max = max_below = 0;
1218         min = min_above = 255;
1219         /* Find closest level to level_current */
1220         for (i = 2; i < device->brightness->count; i++) {
1221                 l = device->brightness->levels[i];
1222                 if (abs(l - level_current) < abs(delta)) {
1223                         delta = l - level_current;
1224                         if (!delta)
1225                                 break;
1226                 }
1227         }
1228         /* Ajust level_current to closest available level */
1229         level_current += delta;
1230         for (i = 2; i < device->brightness->count; i++) {
1231                 l = device->brightness->levels[i];
1232                 if (l < min)
1233                         min = l;
1234                 if (l > max)
1235                         max = l;
1236                 if (l < min_above && l > level_current)
1237                         min_above = l;
1238                 if (l > max_below && l < level_current)
1239                         max_below = l;
1240         }
1241
1242         switch (event) {
1243         case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:
1244                 return (level_current < max) ? min_above : min;
1245         case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:
1246                 return (level_current < max) ? min_above : max;
1247         case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:
1248                 return (level_current > min) ? max_below : min;
1249         case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS:
1250         case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:
1251                 return 0;
1252         default:
1253                 return level_current;
1254         }
1255 }
1256
1257 static int
1258 acpi_video_switch_brightness(struct acpi_video_device *device, int event)
1259 {
1260         unsigned long long level_current, level_next;
1261         int result = -EINVAL;
1262
1263         /* no warning message if acpi_backlight=vendor is used */
1264         if (!acpi_video_backlight_support())
1265                 return 0;
1266
1267         if (!device->brightness)
1268                 goto out;
1269
1270         result = acpi_video_device_lcd_get_level_current(device,
1271                                                          &level_current, 0);
1272         if (result)
1273                 goto out;
1274
1275         level_next = acpi_video_get_next_level(device, level_current, event);
1276
1277         result = acpi_video_device_lcd_set_level(device, level_next);
1278
1279         if (!result)
1280                 backlight_force_update(device->backlight,
1281                                        BACKLIGHT_UPDATE_HOTKEY);
1282
1283 out:
1284         if (result)
1285                 printk(KERN_ERR PREFIX "Failed to switch the brightness\n");
1286
1287         return result;
1288 }
1289
1290 int acpi_video_get_edid(struct acpi_device *device, int type, int device_id,
1291                         void **edid)
1292 {
1293         struct acpi_video_bus *video;
1294         struct acpi_video_device *video_device;
1295         union acpi_object *buffer = NULL;
1296         acpi_status status;
1297         int i, length;
1298
1299         if (!device || !acpi_driver_data(device))
1300                 return -EINVAL;
1301
1302         video = acpi_driver_data(device);
1303
1304         for (i = 0; i < video->attached_count; i++) {
1305                 video_device = video->attached_array[i].bind_info;
1306                 length = 256;
1307
1308                 if (!video_device)
1309                         continue;
1310
1311                 if (!video_device->cap._DDC)
1312                         continue;
1313
1314                 if (type) {
1315                         switch (type) {
1316                         case ACPI_VIDEO_DISPLAY_CRT:
1317                                 if (!video_device->flags.crt)
1318                                         continue;
1319                                 break;
1320                         case ACPI_VIDEO_DISPLAY_TV:
1321                                 if (!video_device->flags.tvout)
1322                                         continue;
1323                                 break;
1324                         case ACPI_VIDEO_DISPLAY_DVI:
1325                                 if (!video_device->flags.dvi)
1326                                         continue;
1327                                 break;
1328                         case ACPI_VIDEO_DISPLAY_LCD:
1329                                 if (!video_device->flags.lcd)
1330                                         continue;
1331                                 break;
1332                         }
1333                 } else if (video_device->device_id != device_id) {
1334                         continue;
1335                 }
1336
1337                 status = acpi_video_device_EDID(video_device, &buffer, length);
1338
1339                 if (ACPI_FAILURE(status) || !buffer ||
1340                     buffer->type != ACPI_TYPE_BUFFER) {
1341                         length = 128;
1342                         status = acpi_video_device_EDID(video_device, &buffer,
1343                                                         length);
1344                         if (ACPI_FAILURE(status) || !buffer ||
1345                             buffer->type != ACPI_TYPE_BUFFER) {
1346                                 continue;
1347                         }
1348                 }
1349
1350                 *edid = buffer->buffer.pointer;
1351                 return length;
1352         }
1353
1354         return -ENODEV;
1355 }
1356 EXPORT_SYMBOL(acpi_video_get_edid);
1357
1358 static int
1359 acpi_video_bus_get_devices(struct acpi_video_bus *video,
1360                            struct acpi_device *device)
1361 {
1362         int status = 0;
1363         struct acpi_device *dev;
1364
1365         /*
1366          * There are systems where video module known to work fine regardless
1367          * of broken _DOD and ignoring returned value here doesn't cause
1368          * any issues later.
1369          */
1370         acpi_video_device_enumerate(video);
1371
1372         list_for_each_entry(dev, &device->children, node) {
1373
1374                 status = acpi_video_bus_get_one_device(dev, video);
1375                 if (status) {
1376                         printk(KERN_WARNING PREFIX
1377                                         "Can't attach device\n");
1378                         continue;
1379                 }
1380         }
1381         return status;
1382 }
1383
1384 static int acpi_video_bus_put_one_device(struct acpi_video_device *device)
1385 {
1386         acpi_status status;
1387
1388         if (!device || !device->video)
1389                 return -ENOENT;
1390
1391         status = acpi_remove_notify_handler(device->dev->handle,
1392                                             ACPI_DEVICE_NOTIFY,
1393                                             acpi_video_device_notify);
1394         if (ACPI_FAILURE(status)) {
1395                 printk(KERN_WARNING PREFIX
1396                        "Can't remove video notify handler\n");
1397         }
1398         if (device->backlight) {
1399                 backlight_device_unregister(device->backlight);
1400                 device->backlight = NULL;
1401         }
1402         if (device->cooling_dev) {
1403                 sysfs_remove_link(&device->dev->dev.kobj,
1404                                   "thermal_cooling");
1405                 sysfs_remove_link(&device->cooling_dev->device.kobj,
1406                                   "device");
1407                 thermal_cooling_device_unregister(device->cooling_dev);
1408                 device->cooling_dev = NULL;
1409         }
1410
1411         return 0;
1412 }
1413
1414 static int acpi_video_bus_put_devices(struct acpi_video_bus *video)
1415 {
1416         int status;
1417         struct acpi_video_device *dev, *next;
1418
1419         mutex_lock(&video->device_list_lock);
1420
1421         list_for_each_entry_safe(dev, next, &video->video_device_list, entry) {
1422
1423                 status = acpi_video_bus_put_one_device(dev);
1424                 if (ACPI_FAILURE(status))
1425                         printk(KERN_WARNING PREFIX
1426                                "hhuuhhuu bug in acpi video driver.\n");
1427
1428                 if (dev->brightness) {
1429                         kfree(dev->brightness->levels);
1430                         kfree(dev->brightness);
1431                 }
1432                 list_del(&dev->entry);
1433                 kfree(dev);
1434         }
1435
1436         mutex_unlock(&video->device_list_lock);
1437
1438         return 0;
1439 }
1440
1441 /* acpi_video interface */
1442
1443 static int acpi_video_bus_start_devices(struct acpi_video_bus *video)
1444 {
1445         return acpi_video_bus_DOS(video, 0, 0);
1446 }
1447
1448 static int acpi_video_bus_stop_devices(struct acpi_video_bus *video)
1449 {
1450         return acpi_video_bus_DOS(video, 0, 1);
1451 }
1452
1453 static void acpi_video_bus_notify(struct acpi_device *device, u32 event)
1454 {
1455         struct acpi_video_bus *video = acpi_driver_data(device);
1456         struct input_dev *input;
1457         int keycode = 0;
1458
1459         if (!video)
1460                 return;
1461
1462         input = video->input;
1463
1464         switch (event) {
1465         case ACPI_VIDEO_NOTIFY_SWITCH:  /* User requested a switch,
1466                                          * most likely via hotkey. */
1467                 acpi_bus_generate_proc_event(device, event, 0);
1468                 keycode = KEY_SWITCHVIDEOMODE;
1469                 break;
1470
1471         case ACPI_VIDEO_NOTIFY_PROBE:   /* User plugged in or removed a video
1472                                          * connector. */
1473                 acpi_video_device_enumerate(video);
1474                 acpi_video_device_rebind(video);
1475                 acpi_bus_generate_proc_event(device, event, 0);
1476                 keycode = KEY_SWITCHVIDEOMODE;
1477                 break;
1478
1479         case ACPI_VIDEO_NOTIFY_CYCLE:   /* Cycle Display output hotkey pressed. */
1480                 acpi_bus_generate_proc_event(device, event, 0);
1481                 keycode = KEY_SWITCHVIDEOMODE;
1482                 break;
1483         case ACPI_VIDEO_NOTIFY_NEXT_OUTPUT:     /* Next Display output hotkey pressed. */
1484                 acpi_bus_generate_proc_event(device, event, 0);
1485                 keycode = KEY_VIDEO_NEXT;
1486                 break;
1487         case ACPI_VIDEO_NOTIFY_PREV_OUTPUT:     /* previous Display output hotkey pressed. */
1488                 acpi_bus_generate_proc_event(device, event, 0);
1489                 keycode = KEY_VIDEO_PREV;
1490                 break;
1491
1492         default:
1493                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1494                                   "Unsupported event [0x%x]\n", event));
1495                 break;
1496         }
1497
1498         if (acpi_notifier_call_chain(device, event, 0))
1499                 /* Something vetoed the keypress. */
1500                 keycode = 0;
1501
1502         if (keycode) {
1503                 input_report_key(input, keycode, 1);
1504                 input_sync(input);
1505                 input_report_key(input, keycode, 0);
1506                 input_sync(input);
1507         }
1508
1509         return;
1510 }
1511
1512 static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data)
1513 {
1514         struct acpi_video_device *video_device = data;
1515         struct acpi_device *device = NULL;
1516         struct acpi_video_bus *bus;
1517         struct input_dev *input;
1518         int keycode = 0;
1519
1520         if (!video_device)
1521                 return;
1522
1523         device = video_device->dev;
1524         bus = video_device->video;
1525         input = bus->input;
1526
1527         switch (event) {
1528         case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:        /* Cycle brightness */
1529                 if (brightness_switch_enabled)
1530                         acpi_video_switch_brightness(video_device, event);
1531                 acpi_bus_generate_proc_event(device, event, 0);
1532                 keycode = KEY_BRIGHTNESS_CYCLE;
1533                 break;
1534         case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:  /* Increase brightness */
1535                 if (brightness_switch_enabled)
1536                         acpi_video_switch_brightness(video_device, event);
1537                 acpi_bus_generate_proc_event(device, event, 0);
1538                 keycode = KEY_BRIGHTNESSUP;
1539                 break;
1540         case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:  /* Decrease brightness */
1541                 if (brightness_switch_enabled)
1542                         acpi_video_switch_brightness(video_device, event);
1543                 acpi_bus_generate_proc_event(device, event, 0);
1544                 keycode = KEY_BRIGHTNESSDOWN;
1545                 break;
1546         case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS: /* zero brightness */
1547                 if (brightness_switch_enabled)
1548                         acpi_video_switch_brightness(video_device, event);
1549                 acpi_bus_generate_proc_event(device, event, 0);
1550                 keycode = KEY_BRIGHTNESS_ZERO;
1551                 break;
1552         case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:     /* display device off */
1553                 if (brightness_switch_enabled)
1554                         acpi_video_switch_brightness(video_device, event);
1555                 acpi_bus_generate_proc_event(device, event, 0);
1556                 keycode = KEY_DISPLAY_OFF;
1557                 break;
1558         default:
1559                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1560                                   "Unsupported event [0x%x]\n", event));
1561                 break;
1562         }
1563
1564         acpi_notifier_call_chain(device, event, 0);
1565
1566         if (keycode) {
1567                 input_report_key(input, keycode, 1);
1568                 input_sync(input);
1569                 input_report_key(input, keycode, 0);
1570                 input_sync(input);
1571         }
1572
1573         return;
1574 }
1575
1576 static int acpi_video_resume(struct notifier_block *nb,
1577                                 unsigned long val, void *ign)
1578 {
1579         struct acpi_video_bus *video;
1580         struct acpi_video_device *video_device;
1581         int i;
1582
1583         switch (val) {
1584         case PM_HIBERNATION_PREPARE:
1585         case PM_SUSPEND_PREPARE:
1586         case PM_RESTORE_PREPARE:
1587                 return NOTIFY_DONE;
1588         }
1589
1590         video = container_of(nb, struct acpi_video_bus, pm_nb);
1591
1592         dev_info(&video->device->dev, "Restoring backlight state\n");
1593
1594         for (i = 0; i < video->attached_count; i++) {
1595                 video_device = video->attached_array[i].bind_info;
1596                 if (video_device && video_device->backlight)
1597                         acpi_video_set_brightness(video_device->backlight);
1598         }
1599
1600         return NOTIFY_OK;
1601 }
1602
1603 static acpi_status
1604 acpi_video_bus_match(acpi_handle handle, u32 level, void *context,
1605                         void **return_value)
1606 {
1607         struct acpi_device *device = context;
1608         struct acpi_device *sibling;
1609         int result;
1610
1611         if (handle == device->handle)
1612                 return AE_CTRL_TERMINATE;
1613
1614         result = acpi_bus_get_device(handle, &sibling);
1615         if (result)
1616                 return AE_OK;
1617
1618         if (!strcmp(acpi_device_name(sibling), ACPI_VIDEO_BUS_NAME))
1619                         return AE_ALREADY_EXISTS;
1620
1621         return AE_OK;
1622 }
1623
1624 static int instance;
1625
1626 static int acpi_video_bus_add(struct acpi_device *device)
1627 {
1628         struct acpi_video_bus *video;
1629         struct input_dev *input;
1630         int error;
1631         acpi_status status;
1632
1633         status = acpi_walk_namespace(ACPI_TYPE_DEVICE,
1634                                 device->parent->handle, 1,
1635                                 acpi_video_bus_match, NULL,
1636                                 device, NULL);
1637         if (status == AE_ALREADY_EXISTS) {
1638                 printk(KERN_WARNING FW_BUG
1639                         "Duplicate ACPI video bus devices for the"
1640                         " same VGA controller, please try module "
1641                         "parameter \"video.allow_duplicates=1\""
1642                         "if the current driver doesn't work.\n");
1643                 if (!allow_duplicates)
1644                         return -ENODEV;
1645         }
1646
1647         video = kzalloc(sizeof(struct acpi_video_bus), GFP_KERNEL);
1648         if (!video)
1649                 return -ENOMEM;
1650
1651         /* a hack to fix the duplicate name "VID" problem on T61 */
1652         if (!strcmp(device->pnp.bus_id, "VID")) {
1653                 if (instance)
1654                         device->pnp.bus_id[3] = '0' + instance;
1655                 instance ++;
1656         }
1657         /* a hack to fix the duplicate name "VGA" problem on Pa 3553 */
1658         if (!strcmp(device->pnp.bus_id, "VGA")) {
1659                 if (instance)
1660                         device->pnp.bus_id[3] = '0' + instance;
1661                 instance++;
1662         }
1663
1664         video->device = device;
1665         strcpy(acpi_device_name(device), ACPI_VIDEO_BUS_NAME);
1666         strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
1667         device->driver_data = video;
1668
1669         acpi_video_bus_find_cap(video);
1670         error = acpi_video_bus_check(video);
1671         if (error)
1672                 goto err_free_video;
1673
1674         mutex_init(&video->device_list_lock);
1675         INIT_LIST_HEAD(&video->video_device_list);
1676
1677         error = acpi_video_bus_get_devices(video, device);
1678         if (error)
1679                 goto err_free_video;
1680
1681         video->input = input = input_allocate_device();
1682         if (!input) {
1683                 error = -ENOMEM;
1684                 goto err_put_video;
1685         }
1686
1687         error = acpi_video_bus_start_devices(video);
1688         if (error)
1689                 goto err_free_input_dev;
1690
1691         snprintf(video->phys, sizeof(video->phys),
1692                 "%s/video/input0", acpi_device_hid(video->device));
1693
1694         input->name = acpi_device_name(video->device);
1695         input->phys = video->phys;
1696         input->id.bustype = BUS_HOST;
1697         input->id.product = 0x06;
1698         input->dev.parent = &device->dev;
1699         input->evbit[0] = BIT(EV_KEY);
1700         set_bit(KEY_SWITCHVIDEOMODE, input->keybit);
1701         set_bit(KEY_VIDEO_NEXT, input->keybit);
1702         set_bit(KEY_VIDEO_PREV, input->keybit);
1703         set_bit(KEY_BRIGHTNESS_CYCLE, input->keybit);
1704         set_bit(KEY_BRIGHTNESSUP, input->keybit);
1705         set_bit(KEY_BRIGHTNESSDOWN, input->keybit);
1706         set_bit(KEY_BRIGHTNESS_ZERO, input->keybit);
1707         set_bit(KEY_DISPLAY_OFF, input->keybit);
1708
1709         printk(KERN_INFO PREFIX "%s [%s] (multi-head: %s  rom: %s  post: %s)\n",
1710                ACPI_VIDEO_DEVICE_NAME, acpi_device_bid(device),
1711                video->flags.multihead ? "yes" : "no",
1712                video->flags.rom ? "yes" : "no",
1713                video->flags.post ? "yes" : "no");
1714
1715         video->pm_nb.notifier_call = acpi_video_resume;
1716         video->pm_nb.priority = 0;
1717         error = register_pm_notifier(&video->pm_nb);
1718         if (error)
1719                 goto err_stop_video;
1720
1721         error = input_register_device(input);
1722         if (error)
1723                 goto err_unregister_pm_notifier;
1724
1725         return 0;
1726
1727  err_unregister_pm_notifier:
1728         unregister_pm_notifier(&video->pm_nb);
1729  err_stop_video:
1730         acpi_video_bus_stop_devices(video);
1731  err_free_input_dev:
1732         input_free_device(input);
1733  err_put_video:
1734         acpi_video_bus_put_devices(video);
1735         kfree(video->attached_array);
1736  err_free_video:
1737         kfree(video);
1738         device->driver_data = NULL;
1739
1740         return error;
1741 }
1742
1743 static int acpi_video_bus_remove(struct acpi_device *device, int type)
1744 {
1745         struct acpi_video_bus *video = NULL;
1746
1747
1748         if (!device || !acpi_driver_data(device))
1749                 return -EINVAL;
1750
1751         video = acpi_driver_data(device);
1752
1753         unregister_pm_notifier(&video->pm_nb);
1754
1755         acpi_video_bus_stop_devices(video);
1756         acpi_video_bus_put_devices(video);
1757
1758         input_unregister_device(video->input);
1759         kfree(video->attached_array);
1760         kfree(video);
1761
1762         return 0;
1763 }
1764
1765 static int __init is_i740(struct pci_dev *dev)
1766 {
1767         if (dev->device == 0x00D1)
1768                 return 1;
1769         if (dev->device == 0x7000)
1770                 return 1;
1771         return 0;
1772 }
1773
1774 static int __init intel_opregion_present(void)
1775 {
1776         int opregion = 0;
1777         struct pci_dev *dev = NULL;
1778         u32 address;
1779
1780         for_each_pci_dev(dev) {
1781                 if ((dev->class >> 8) != PCI_CLASS_DISPLAY_VGA)
1782                         continue;
1783                 if (dev->vendor != PCI_VENDOR_ID_INTEL)
1784                         continue;
1785                 /* We don't want to poke around undefined i740 registers */
1786                 if (is_i740(dev))
1787                         continue;
1788                 pci_read_config_dword(dev, 0xfc, &address);
1789                 if (!address)
1790                         continue;
1791                 opregion = 1;
1792         }
1793         return opregion;
1794 }
1795
1796 int acpi_video_register(void)
1797 {
1798         int result = 0;
1799         if (register_count) {
1800                 /*
1801                  * if the function of acpi_video_register is already called,
1802                  * don't register the acpi_vide_bus again and return no error.
1803                  */
1804                 return 0;
1805         }
1806
1807         result = acpi_bus_register_driver(&acpi_video_bus);
1808         if (result < 0)
1809                 return -ENODEV;
1810
1811         /*
1812          * When the acpi_video_bus is loaded successfully, increase
1813          * the counter reference.
1814          */
1815         register_count = 1;
1816
1817         return 0;
1818 }
1819 EXPORT_SYMBOL(acpi_video_register);
1820
1821 void acpi_video_unregister(void)
1822 {
1823         if (!register_count) {
1824                 /*
1825                  * If the acpi video bus is already unloaded, don't
1826                  * unload it again and return directly.
1827                  */
1828                 return;
1829         }
1830         acpi_bus_unregister_driver(&acpi_video_bus);
1831
1832         register_count = 0;
1833
1834         return;
1835 }
1836 EXPORT_SYMBOL(acpi_video_unregister);
1837
1838 /*
1839  * This is kind of nasty. Hardware using Intel chipsets may require
1840  * the video opregion code to be run first in order to initialise
1841  * state before any ACPI video calls are made. To handle this we defer
1842  * registration of the video class until the opregion code has run.
1843  */
1844
1845 static int __init acpi_video_init(void)
1846 {
1847         dmi_check_system(video_dmi_table);
1848
1849         if (intel_opregion_present())
1850                 return 0;
1851
1852         return acpi_video_register();
1853 }
1854
1855 static void __exit acpi_video_exit(void)
1856 {
1857         acpi_video_unregister();
1858
1859         return;
1860 }
1861
1862 module_init(acpi_video_init);
1863 module_exit(acpi_video_exit);