Pileus Git - ~andy/linux/blob - drivers/acpi/video.c

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