drivers/acpi/acpi_video.c

   1 /*
   2  *  video.c - ACPI Video Driver
   3  *
   4  *  Copyright (C) 2004 Luming Yu <luming.yu@intel.com>
   5  *  Copyright (C) 2004 Bruno Ducrot <ducrot@poupinou.org>
   6  *  Copyright (C) 2006 Thomas Tuttle <linux-kernel@ttuttle.net>
   7  *
   8  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   9  *
  10  *  This program is free software; you can redistribute it and/or modify
  11  *  it under the terms of the GNU General Public License as published by
  12  *  the Free Software Foundation; either version 2 of the License, or (at
  13  *  your option) any later version.
  14  *
  15  *  This program is distributed in the hope that it will be useful, but
  16  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  17  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  *  General Public License for more details.
  19  *
  20  *  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 <linux/dmi.h>
  41 #include <linux/suspend.h>
  42 #include <linux/acpi.h>
  43 #include <acpi/video.h>
  44 #include <asm/uaccess.h>
  45
  46 #define PREFIX "ACPI: "
  47
  48 #define ACPI_VIDEO_BUS_NAME             "Video Bus"
  49 #define ACPI_VIDEO_DEVICE_NAME          "Video Device"
  50 #define ACPI_VIDEO_NOTIFY_SWITCH        0x80
  51 #define ACPI_VIDEO_NOTIFY_PROBE         0x81
  52 #define ACPI_VIDEO_NOTIFY_CYCLE         0x82
  53 #define ACPI_VIDEO_NOTIFY_NEXT_OUTPUT   0x83
  54 #define ACPI_VIDEO_NOTIFY_PREV_OUTPUT   0x84
  55
  56 #define ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS      0x85
  57 #define ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS        0x86
  58 #define ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS        0x87
  59 #define ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS       0x88
  60 #define ACPI_VIDEO_NOTIFY_DISPLAY_OFF           0x89
  61
  62 #define MAX_NAME_LEN    20
  63
  64 #define _COMPONENT              ACPI_VIDEO_COMPONENT
  65 ACPI_MODULE_NAME("video");
  66
  67 MODULE_AUTHOR("Bruno Ducrot");
  68 MODULE_DESCRIPTION("ACPI Video Driver");
  69 MODULE_LICENSE("GPL");
  70
  71 static bool brightness_switch_enabled = 1;
  72 module_param(brightness_switch_enabled, bool, 0644);
  73
  74 /*
  75  * By default, we don't allow duplicate ACPI video bus devices
  76  * under the same VGA controller
  77  */
  78 static bool allow_duplicates;
  79 module_param(allow_duplicates, bool, 0644);
  80
  81 static int disable_backlight_sysfs_if = -1;
  82 module_param(disable_backlight_sysfs_if, int, 0444);
  83
  84 static int register_count;
  85 static DEFINE_MUTEX(register_count_mutex);
  86 static struct mutex video_list_lock;
  87 static struct list_head video_bus_head;
  88 static int acpi_video_bus_add(struct acpi_device *device);
  89 static int acpi_video_bus_remove(struct acpi_device *device);
  90 static void acpi_video_bus_notify(struct acpi_device *device, u32 event);
  91 void acpi_video_detect_exit(void);
  92
  93 static const struct acpi_device_id video_device_ids[] = {
  94         {ACPI_VIDEO_HID, 0},
  95         {"", 0},
  96 };
  97 MODULE_DEVICE_TABLE(acpi, video_device_ids);
  98
  99 static struct acpi_driver acpi_video_bus = {
 100         .name = "video",
 101         .class = ACPI_VIDEO_CLASS,
 102         .ids = video_device_ids,
 103         .ops = {
 104                 .add = acpi_video_bus_add,
 105                 .remove = acpi_video_bus_remove,
 106                 .notify = acpi_video_bus_notify,
 107                 },
 108 };
 109
 110 struct acpi_video_bus_flags {
 111         u8 multihead:1;         /* can switch video heads */
 112         u8 rom:1;               /* can retrieve a video rom */
 113         u8 post:1;              /* can configure the head to */
 114         u8 reserved:5;
 115 };
 116
 117 struct acpi_video_bus_cap {
 118         u8 _DOS:1;              /* Enable/Disable output switching */
 119         u8 _DOD:1;              /* Enumerate all devices attached to display adapter */
 120         u8 _ROM:1;              /* Get ROM Data */
 121         u8 _GPD:1;              /* Get POST Device */
 122         u8 _SPD:1;              /* Set POST Device */
 123         u8 _VPO:1;              /* Video POST Options */
 124         u8 reserved:2;
 125 };
 126
 127 struct acpi_video_device_attrib {
 128         u32 display_index:4;    /* A zero-based instance of the Display */
 129         u32 display_port_attachment:4;  /* This field differentiates the display type */
 130         u32 display_type:4;     /* Describe the specific type in use */
 131         u32 vendor_specific:4;  /* Chipset Vendor Specific */
 132         u32 bios_can_detect:1;  /* BIOS can detect the device */
 133         u32 depend_on_vga:1;    /* Non-VGA output device whose power is related to
 134                                    the VGA device. */
 135         u32 pipe_id:3;          /* For VGA multiple-head devices. */
 136         u32 reserved:10;        /* Must be 0 */
 137         u32 device_id_scheme:1; /* Device ID Scheme */
 138 };
 139
 140 struct acpi_video_enumerated_device {
 141         union {
 142                 u32 int_val;
 143                 struct acpi_video_device_attrib attrib;
 144         } value;
 145         struct acpi_video_device *bind_info;
 146 };
 147
 148 struct acpi_video_bus {
 149         struct acpi_device *device;
 150         bool backlight_registered;
 151         u8 dos_setting;
 152         struct acpi_video_enumerated_device *attached_array;
 153         u8 attached_count;
 154         u8 child_count;
 155         struct acpi_video_bus_cap cap;
 156         struct acpi_video_bus_flags flags;
 157         struct list_head video_device_list;
 158         struct mutex device_list_lock;  /* protects video_device_list */
 159         struct list_head entry;
 160         struct input_dev *input;
 161         char phys[32];  /* for input device */
 162         struct notifier_block pm_nb;
 163 };
 164
 165 struct acpi_video_device_flags {
 166         u8 crt:1;
 167         u8 lcd:1;
 168         u8 tvout:1;
 169         u8 dvi:1;
 170         u8 bios:1;
 171         u8 unknown:1;
 172         u8 notify:1;
 173         u8 reserved:1;
 174 };
 175
 176 struct acpi_video_device_cap {
 177         u8 _ADR:1;              /* Return the unique ID */
 178         u8 _BCL:1;              /* Query list of brightness control levels supported */
 179         u8 _BCM:1;              /* Set the brightness level */
 180         u8 _BQC:1;              /* Get current brightness level */
 181         u8 _BCQ:1;              /* Some buggy BIOS uses _BCQ instead of _BQC */
 182         u8 _DDC:1;              /* Return the EDID for this device */
 183 };
 184
 185 struct acpi_video_brightness_flags {
 186         u8 _BCL_no_ac_battery_levels:1; /* no AC/Battery levels in _BCL */
 187         u8 _BCL_reversed:1;             /* _BCL package is in a reversed order */
 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 delayed_work switch_brightness_work;
 204         int switch_brightness_event;
 205         struct acpi_video_bus *video;
 206         struct acpi_device *dev;
 207         struct acpi_video_device_brightness *brightness;
 208         struct backlight_device *backlight;
 209         struct thermal_cooling_device *cooling_dev;
 210 };
 211
 212 static const char device_decode[][30] = {
 213         "motherboard VGA device",
 214         "PCI VGA device",
 215         "AGP VGA device",
 216         "UNKNOWN",
 217 };
 218
 219 static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data);
 220 static void acpi_video_device_rebind(struct acpi_video_bus *video);
 221 static void acpi_video_device_bind(struct acpi_video_bus *video,
 222                                    struct acpi_video_device *device);
 223 static int acpi_video_device_enumerate(struct acpi_video_bus *video);
 224 static int acpi_video_device_lcd_set_level(struct acpi_video_device *device,
 225                         int level);
 226 static int acpi_video_device_lcd_get_level_current(
 227                         struct acpi_video_device *device,
 228                         unsigned long long *level, bool raw);
 229 static int acpi_video_get_next_level(struct acpi_video_device *device,
 230                                      u32 level_current, u32 event);
 231 static void acpi_video_switch_brightness(struct work_struct *work);
 232
 233 /* backlight device sysfs support */
 234 static int acpi_video_get_brightness(struct backlight_device *bd)
 235 {
 236         unsigned long long cur_level;
 237         int i;
 238         struct acpi_video_device *vd = 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                         /*
 245                          * The first two entries are special - see page 575
 246                          * of the ACPI spec 3.0
 247                          */
 248                         return i - 2;
 249         }
 250         return 0;
 251 }
 252
 253 static int acpi_video_set_brightness(struct backlight_device *bd)
 254 {
 255         int request_level = bd->props.brightness + 2;
 256         struct acpi_video_device *vd = bl_get_data(bd);
 257
 258         cancel_delayed_work(&vd->switch_brightness_work);
 259         return acpi_video_device_lcd_set_level(vd,
 260                                 vd->brightness->levels[request_level]);
 261 }
 262
 263 static const struct backlight_ops acpi_backlight_ops = {
 264         .get_brightness = acpi_video_get_brightness,
 265         .update_status  = acpi_video_set_brightness,
 266 };
 267
 268 /* thermal cooling device callbacks */
 269 static int video_get_max_state(struct thermal_cooling_device *cooling_dev, unsigned
 270                                long *state)
 271 {
 272         struct acpi_device *device = cooling_dev->devdata;
 273         struct acpi_video_device *video = acpi_driver_data(device);
 274
 275         *state = video->brightness->count - 3;
 276         return 0;
 277 }
 278
 279 static int video_get_cur_state(struct thermal_cooling_device *cooling_dev, unsigned
 280                                long *state)
 281 {
 282         struct acpi_device *device = cooling_dev->devdata;
 283         struct acpi_video_device *video = acpi_driver_data(device);
 284         unsigned long long level;
 285         int offset;
 286
 287         if (acpi_video_device_lcd_get_level_current(video, &level, false))
 288                 return -EINVAL;
 289         for (offset = 2; offset < video->brightness->count; offset++)
 290                 if (level == video->brightness->levels[offset]) {
 291                         *state = video->brightness->count - offset - 1;
 292                         return 0;
 293                 }
 294
 295         return -EINVAL;
 296 }
 297
 298 static int
 299 video_set_cur_state(struct thermal_cooling_device *cooling_dev, unsigned long state)
 300 {
 301         struct acpi_device *device = cooling_dev->devdata;
 302         struct acpi_video_device *video = acpi_driver_data(device);
 303         int level;
 304
 305         if (state >= video->brightness->count - 2)
 306                 return -EINVAL;
 307
 308         state = video->brightness->count - state;
 309         level = video->brightness->levels[state - 1];
 310         return acpi_video_device_lcd_set_level(video, level);
 311 }
 312
 313 static const struct thermal_cooling_device_ops video_cooling_ops = {
 314         .get_max_state = video_get_max_state,
 315         .get_cur_state = video_get_cur_state,
 316         .set_cur_state = video_set_cur_state,
 317 };
 318
 319 /*
 320  * --------------------------------------------------------------------------
 321  *                             Video Management
 322  * --------------------------------------------------------------------------
 323  */
 324
 325 static int
 326 acpi_video_device_lcd_query_levels(struct acpi_video_device *device,
 327                                    union acpi_object **levels)
 328 {
 329         int status;
 330         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 331         union acpi_object *obj;
 332
 333
 334         *levels = NULL;
 335
 336         status = acpi_evaluate_object(device->dev->handle, "_BCL", NULL, &buffer);
 337         if (!ACPI_SUCCESS(status))
 338                 return status;
 339         obj = (union acpi_object *)buffer.pointer;
 340         if (!obj || (obj->type != ACPI_TYPE_PACKAGE)) {
 341                 printk(KERN_ERR PREFIX "Invalid _BCL data\n");
 342                 status = -EFAULT;
 343                 goto err;
 344         }
 345
 346         *levels = obj;
 347
 348         return 0;
 349
 350 err:
 351         kfree(buffer.pointer);
 352
 353         return status;
 354 }
 355
 356 static int
 357 acpi_video_device_lcd_set_level(struct acpi_video_device *device, int level)
 358 {
 359         int status;
 360         int state;
 361
 362         status = acpi_execute_simple_method(device->dev->handle,
 363                                             "_BCM", level);
 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 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_disable_backlight_sysfs_if(
 394         const struct dmi_system_id *d)
 395 {
 396         if (disable_backlight_sysfs_if == -1)
 397                 disable_backlight_sysfs_if = 1;
 398         return 0;
 399 }
 400
 401 static struct dmi_system_id video_dmi_table[] = {
 402         /*
 403          * Broken _BQC workaround http://bugzilla.kernel.org/show_bug.cgi?id=13121
 404          */
 405         {
 406          .callback = video_set_bqc_offset,
 407          .ident = "Acer Aspire 5720",
 408          .matches = {
 409                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
 410                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5720"),
 411                 },
 412         },
 413         {
 414          .callback = video_set_bqc_offset,
 415          .ident = "Acer Aspire 5710Z",
 416          .matches = {
 417                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
 418                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5710Z"),
 419                 },
 420         },
 421         {
 422          .callback = video_set_bqc_offset,
 423          .ident = "eMachines E510",
 424          .matches = {
 425                 DMI_MATCH(DMI_BOARD_VENDOR, "EMACHINES"),
 426                 DMI_MATCH(DMI_PRODUCT_NAME, "eMachines E510"),
 427                 },
 428         },
 429         {
 430          .callback = video_set_bqc_offset,
 431          .ident = "Acer Aspire 5315",
 432          .matches = {
 433                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
 434                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5315"),
 435                 },
 436         },
 437         {
 438          .callback = video_set_bqc_offset,
 439          .ident = "Acer Aspire 7720",
 440          .matches = {
 441                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
 442                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 7720"),
 443                 },
 444         },
 445
 446         /*
 447          * Some machines have a broken acpi-video interface for brightness
 448          * control, but still need an acpi_video_device_lcd_set_level() call
 449          * on resume to turn the backlight power on.  We Enable backlight
 450          * control on these systems, but do not register a backlight sysfs
 451          * as brightness control does not work.
 452          */
 453         {
 454          /* https://bugs.freedesktop.org/show_bug.cgi?id=82634 */
 455          .callback = video_disable_backlight_sysfs_if,
 456          .ident = "Toshiba Portege R830",
 457          .matches = {
 458                 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
 459                 DMI_MATCH(DMI_PRODUCT_NAME, "PORTEGE R830"),
 460                 },
 461         },
 462         {}
 463 };
 464
 465 static unsigned long long
 466 acpi_video_bqc_value_to_level(struct acpi_video_device *device,
 467                               unsigned long long bqc_value)
 468 {
 469         unsigned long long level;
 470
 471         if (device->brightness->flags._BQC_use_index) {
 472                 /*
 473                  * _BQC returns an index that doesn't account for
 474                  * the first 2 items with special meaning, so we need
 475                  * to compensate for that by offsetting ourselves
 476                  */
 477                 if (device->brightness->flags._BCL_reversed)
 478                         bqc_value = device->brightness->count - 3 - bqc_value;
 479
 480                 level = device->brightness->levels[bqc_value + 2];
 481         } else {
 482                 level = bqc_value;
 483         }
 484
 485         level += bqc_offset_aml_bug_workaround;
 486
 487         return level;
 488 }
 489
 490 static int
 491 acpi_video_device_lcd_get_level_current(struct acpi_video_device *device,
 492                                         unsigned long long *level, bool raw)
 493 {
 494         acpi_status status = AE_OK;
 495         int i;
 496
 497         if (device->cap._BQC || device->cap._BCQ) {
 498                 char *buf = device->cap._BQC ? "_BQC" : "_BCQ";
 499
 500                 status = acpi_evaluate_integer(device->dev->handle, buf,
 501                                                 NULL, level);
 502                 if (ACPI_SUCCESS(status)) {
 503                         if (raw) {
 504                                 /*
 505                                  * Caller has indicated he wants the raw
 506                                  * value returned by _BQC, so don't furtherly
 507                                  * mess with the value.
 508                                  */
 509                                 return 0;
 510                         }
 511
 512                         *level = acpi_video_bqc_value_to_level(device, *level);
 513
 514                         for (i = 2; i < device->brightness->count; i++)
 515                                 if (device->brightness->levels[i] == *level) {
 516                                         device->brightness->curr = *level;
 517                                         return 0;
 518                                 }
 519                         /*
 520                          * BQC returned an invalid level.
 521                          * Stop using it.
 522                          */
 523                         ACPI_WARNING((AE_INFO,
 524                                       "%s returned an invalid level",
 525                                       buf));
 526                         device->cap._BQC = device->cap._BCQ = 0;
 527                 } else {
 528                         /*
 529                          * Fixme:
 530                          * should we return an error or ignore this failure?
 531                          * dev->brightness->curr is a cached value which stores
 532                          * the correct current backlight level in most cases.
 533                          * ACPI video backlight still works w/ buggy _BQC.
 534                          * http://bugzilla.kernel.org/show_bug.cgi?id=12233
 535                          */
 536                         ACPI_WARNING((AE_INFO, "Evaluating %s failed", buf));
 537                         device->cap._BQC = device->cap._BCQ = 0;
 538                 }
 539         }
 540
 541         *level = device->brightness->curr;
 542         return 0;
 543 }
 544
 545 static int
 546 acpi_video_device_EDID(struct acpi_video_device *device,
 547                        union acpi_object **edid, ssize_t length)
 548 {
 549         int status;
 550         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 551         union acpi_object *obj;
 552         union acpi_object arg0 = { ACPI_TYPE_INTEGER };
 553         struct acpi_object_list args = { 1, &arg0 };
 554
 555
 556         *edid = NULL;
 557
 558         if (!device)
 559                 return -ENODEV;
 560         if (length == 128)
 561                 arg0.integer.value = 1;
 562         else if (length == 256)
 563                 arg0.integer.value = 2;
 564         else
 565                 return -EINVAL;
 566
 567         status = acpi_evaluate_object(device->dev->handle, "_DDC", &args, &buffer);
 568         if (ACPI_FAILURE(status))
 569                 return -ENODEV;
 570
 571         obj = buffer.pointer;
 572
 573         if (obj && obj->type == ACPI_TYPE_BUFFER)
 574                 *edid = obj;
 575         else {
 576                 printk(KERN_ERR PREFIX "Invalid _DDC data\n");
 577                 status = -EFAULT;
 578                 kfree(obj);
 579         }
 580
 581         return status;
 582 }
 583
 584 /* bus */
 585
 586 /*
 587  *  Arg:
 588  *      video           : video bus device pointer
 589  *      bios_flag       :
 590  *              0.      The system BIOS should NOT automatically switch(toggle)
 591  *                      the active display output.
 592  *              1.      The system BIOS should automatically switch (toggle) the
 593  *                      active display output. No switch event.
 594  *              2.      The _DGS value should be locked.
 595  *              3.      The system BIOS should not automatically switch (toggle) the
 596  *                      active display output, but instead generate the display switch
 597  *                      event notify code.
 598  *      lcd_flag        :
 599  *              0.      The system BIOS should automatically control the brightness level
 600  *                      of the LCD when the power changes from AC to DC
 601  *              1.      The system BIOS should NOT automatically control the brightness
 602  *                      level of the LCD when the power changes from AC to DC.
 603  *  Return Value:
 604  *              -EINVAL wrong arg.
 605  */
 606
 607 static int
 608 acpi_video_bus_DOS(struct acpi_video_bus *video, int bios_flag, int lcd_flag)
 609 {
 610         acpi_status status;
 611
 612         if (!video->cap._DOS)
 613                 return 0;
 614
 615         if (bios_flag < 0 || bios_flag > 3 || lcd_flag < 0 || lcd_flag > 1)
 616                 return -EINVAL;
 617         video->dos_setting = (lcd_flag << 2) | bios_flag;
 618         status = acpi_execute_simple_method(video->device->handle, "_DOS",
 619                                             (lcd_flag << 2) | bios_flag);
 620         if (ACPI_FAILURE(status))
 621                 return -EIO;
 622
 623         return 0;
 624 }
 625
 626 /*
 627  * Simple comparison function used to sort backlight levels.
 628  */
 629
 630 static int
 631 acpi_video_cmp_level(const void *a, const void *b)
 632 {
 633         return *(int *)a - *(int *)b;
 634 }
 635
 636 /*
 637  * Decides if _BQC/_BCQ for this system is usable
 638  *
 639  * We do this by changing the level first and then read out the current
 640  * brightness level, if the value does not match, find out if it is using
 641  * index. If not, clear the _BQC/_BCQ capability.
 642  */
 643 static int acpi_video_bqc_quirk(struct acpi_video_device *device,
 644                                 int max_level, int current_level)
 645 {
 646         struct acpi_video_device_brightness *br = device->brightness;
 647         int result;
 648         unsigned long long level;
 649         int test_level;
 650
 651         /* don't mess with existing known broken systems */
 652         if (bqc_offset_aml_bug_workaround)
 653                 return 0;
 654
 655         /*
 656          * Some systems always report current brightness level as maximum
 657          * through _BQC, we need to test another value for them.
 658          */
 659         test_level = current_level == max_level ? br->levels[3] : max_level;
 660
 661         result = acpi_video_device_lcd_set_level(device, test_level);
 662         if (result)
 663                 return result;
 664
 665         result = acpi_video_device_lcd_get_level_current(device, &level, true);
 666         if (result)
 667                 return result;
 668
 669         if (level != test_level) {
 670                 /* buggy _BQC found, need to find out if it uses index */
 671                 if (level < br->count) {
 672                         if (br->flags._BCL_reversed)
 673                                 level = br->count - 3 - level;
 674                         if (br->levels[level + 2] == test_level)
 675                                 br->flags._BQC_use_index = 1;
 676                 }
 677
 678                 if (!br->flags._BQC_use_index)
 679                         device->cap._BQC = device->cap._BCQ = 0;
 680         }
 681
 682         return 0;
 683 }
 684
 685
 686 /*
 687  *  Arg:
 688  *      device  : video output device (LCD, CRT, ..)
 689  *
 690  *  Return Value:
 691  *      Maximum brightness level
 692  *
 693  *  Allocate and initialize device->brightness.
 694  */
 695
 696 static int
 697 acpi_video_init_brightness(struct acpi_video_device *device)
 698 {
 699         union acpi_object *obj = NULL;
 700         int i, max_level = 0, count = 0, level_ac_battery = 0;
 701         unsigned long long level, level_old;
 702         union acpi_object *o;
 703         struct acpi_video_device_brightness *br = NULL;
 704         int result = -EINVAL;
 705         u32 value;
 706
 707         if (!ACPI_SUCCESS(acpi_video_device_lcd_query_levels(device, &obj))) {
 708                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Could not query available "
 709                                                 "LCD brightness level\n"));
 710                 goto out;
 711         }
 712
 713         if (obj->package.count < 2)
 714                 goto out;
 715
 716         br = kzalloc(sizeof(*br), GFP_KERNEL);
 717         if (!br) {
 718                 printk(KERN_ERR "can't allocate memory\n");
 719                 result = -ENOMEM;
 720                 goto out;
 721         }
 722
 723         br->levels = kmalloc((obj->package.count + 2) * sizeof *(br->levels),
 724                                 GFP_KERNEL);
 725         if (!br->levels) {
 726                 result = -ENOMEM;
 727                 goto out_free;
 728         }
 729
 730         for (i = 0; i < obj->package.count; i++) {
 731                 o = (union acpi_object *)&obj->package.elements[i];
 732                 if (o->type != ACPI_TYPE_INTEGER) {
 733                         printk(KERN_ERR PREFIX "Invalid data\n");
 734                         continue;
 735                 }
 736                 value = (u32) o->integer.value;
 737                 /* Skip duplicate entries */
 738                 if (count > 2 && br->levels[count - 1] == value)
 739                         continue;
 740
 741                 br->levels[count] = value;
 742
 743                 if (br->levels[count] > max_level)
 744                         max_level = br->levels[count];
 745                 count++;
 746         }
 747
 748         /*
 749          * some buggy BIOS don't export the levels
 750          * when machine is on AC/Battery in _BCL package.
 751          * In this case, the first two elements in _BCL packages
 752          * are also supported brightness levels that OS should take care of.
 753          */
 754         for (i = 2; i < count; i++) {
 755                 if (br->levels[i] == br->levels[0])
 756                         level_ac_battery++;
 757                 if (br->levels[i] == br->levels[1])
 758                         level_ac_battery++;
 759         }
 760
 761         if (level_ac_battery < 2) {
 762                 level_ac_battery = 2 - level_ac_battery;
 763                 br->flags._BCL_no_ac_battery_levels = 1;
 764                 for (i = (count - 1 + level_ac_battery); i >= 2; i--)
 765                         br->levels[i] = br->levels[i - level_ac_battery];
 766                 count += level_ac_battery;
 767         } else if (level_ac_battery > 2)
 768                 ACPI_ERROR((AE_INFO, "Too many duplicates in _BCL package"));
 769
 770         /* Check if the _BCL package is in a reversed order */
 771         if (max_level == br->levels[2]) {
 772                 br->flags._BCL_reversed = 1;
 773                 sort(&br->levels[2], count - 2, sizeof(br->levels[2]),
 774                         acpi_video_cmp_level, NULL);
 775         } else if (max_level != br->levels[count - 1])
 776                 ACPI_ERROR((AE_INFO,
 777                             "Found unordered _BCL package"));
 778
 779         br->count = count;
 780         device->brightness = br;
 781
 782         /* _BQC uses INDEX while _BCL uses VALUE in some laptops */
 783         br->curr = level = max_level;
 784
 785         if (!device->cap._BQC)
 786                 goto set_level;
 787
 788         result = acpi_video_device_lcd_get_level_current(device,
 789                                                          &level_old, true);
 790         if (result)
 791                 goto out_free_levels;
 792
 793         result = acpi_video_bqc_quirk(device, max_level, level_old);
 794         if (result)
 795                 goto out_free_levels;
 796         /*
 797          * cap._BQC may get cleared due to _BQC is found to be broken
 798          * in acpi_video_bqc_quirk, so check again here.
 799          */
 800         if (!device->cap._BQC)
 801                 goto set_level;
 802
 803         level = acpi_video_bqc_value_to_level(device, level_old);
 804         /*
 805          * On some buggy laptops, _BQC returns an uninitialized
 806          * value when invoked for the first time, i.e.
 807          * level_old is invalid (no matter whether it's a level
 808          * or an index). Set the backlight to max_level in this case.
 809          */
 810         for (i = 2; i < br->count; i++)
 811                 if (level == br->levels[i])
 812                         break;
 813         if (i == br->count || !level)
 814                 level = max_level;
 815
 816 set_level:
 817         result = acpi_video_device_lcd_set_level(device, level);
 818         if (result)
 819                 goto out_free_levels;
 820
 821         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 822                           "found %d brightness levels\n", count - 2));
 823         kfree(obj);
 824         return result;
 825
 826 out_free_levels:
 827         kfree(br->levels);
 828 out_free:
 829         kfree(br);
 830 out:
 831         device->brightness = NULL;
 832         kfree(obj);
 833         return result;
 834 }
 835
 836 /*
 837  *  Arg:
 838  *      device  : video output device (LCD, CRT, ..)
 839  *
 840  *  Return Value:
 841  *      None
 842  *
 843  *  Find out all required AML methods defined under the output
 844  *  device.
 845  */
 846
 847 static void acpi_video_device_find_cap(struct acpi_video_device *device)
 848 {
 849         if (acpi_has_method(device->dev->handle, "_ADR"))
 850                 device->cap._ADR = 1;
 851         if (acpi_has_method(device->dev->handle, "_BCL"))
 852                 device->cap._BCL = 1;
 853         if (acpi_has_method(device->dev->handle, "_BCM"))
 854                 device->cap._BCM = 1;
 855         if (acpi_has_method(device->dev->handle, "_BQC")) {
 856                 device->cap._BQC = 1;
 857         } else if (acpi_has_method(device->dev->handle, "_BCQ")) {
 858                 printk(KERN_WARNING FW_BUG "_BCQ is used instead of _BQC\n");
 859                 device->cap._BCQ = 1;
 860         }
 861
 862         if (acpi_has_method(device->dev->handle, "_DDC"))
 863                 device->cap._DDC = 1;
 864 }
 865
 866 /*
 867  *  Arg:
 868  *      device  : video output device (VGA)
 869  *
 870  *  Return Value:
 871  *      None
 872  *
 873  *  Find out all required AML methods defined under the video bus device.
 874  */
 875
 876 static void acpi_video_bus_find_cap(struct acpi_video_bus *video)
 877 {
 878         if (acpi_has_method(video->device->handle, "_DOS"))
 879                 video->cap._DOS = 1;
 880         if (acpi_has_method(video->device->handle, "_DOD"))
 881                 video->cap._DOD = 1;
 882         if (acpi_has_method(video->device->handle, "_ROM"))
 883                 video->cap._ROM = 1;
 884         if (acpi_has_method(video->device->handle, "_GPD"))
 885                 video->cap._GPD = 1;
 886         if (acpi_has_method(video->device->handle, "_SPD"))
 887                 video->cap._SPD = 1;
 888         if (acpi_has_method(video->device->handle, "_VPO"))
 889                 video->cap._VPO = 1;
 890 }
 891
 892 /*
 893  * Check whether the video bus device has required AML method to
 894  * support the desired features
 895  */
 896
 897 static int acpi_video_bus_check(struct acpi_video_bus *video)
 898 {
 899         acpi_status status = -ENOENT;
 900         struct pci_dev *dev;
 901
 902         if (!video)
 903                 return -EINVAL;
 904
 905         dev = acpi_get_pci_dev(video->device->handle);
 906         if (!dev)
 907                 return -ENODEV;
 908         pci_dev_put(dev);
 909
 910         /*
 911          * Since there is no HID, CID and so on for VGA driver, we have
 912          * to check well known required nodes.
 913          */
 914
 915         /* Does this device support video switching? */
 916         if (video->cap._DOS || video->cap._DOD) {
 917                 if (!video->cap._DOS) {
 918                         printk(KERN_WARNING FW_BUG
 919                                 "ACPI(%s) defines _DOD but not _DOS\n",
 920                                 acpi_device_bid(video->device));
 921                 }
 922                 video->flags.multihead = 1;
 923                 status = 0;
 924         }
 925
 926         /* Does this device support retrieving a video ROM? */
 927         if (video->cap._ROM) {
 928                 video->flags.rom = 1;
 929                 status = 0;
 930         }
 931
 932         /* Does this device support configuring which video device to POST? */
 933         if (video->cap._GPD && video->cap._SPD && video->cap._VPO) {
 934                 video->flags.post = 1;
 935                 status = 0;
 936         }
 937
 938         return status;
 939 }
 940
 941 /*
 942  * --------------------------------------------------------------------------
 943  *                               Driver Interface
 944  * --------------------------------------------------------------------------
 945  */
 946
 947 /* device interface */
 948 static struct acpi_video_device_attrib *
 949 acpi_video_get_device_attr(struct acpi_video_bus *video, unsigned long device_id)
 950 {
 951         struct acpi_video_enumerated_device *ids;
 952         int i;
 953
 954         for (i = 0; i < video->attached_count; i++) {
 955                 ids = &video->attached_array[i];
 956                 if ((ids->value.int_val & 0xffff) == device_id)
 957                         return &ids->value.attrib;
 958         }
 959
 960         return NULL;
 961 }
 962
 963 static int
 964 acpi_video_get_device_type(struct acpi_video_bus *video,
 965                            unsigned long device_id)
 966 {
 967         struct acpi_video_enumerated_device *ids;
 968         int i;
 969
 970         for (i = 0; i < video->attached_count; i++) {
 971                 ids = &video->attached_array[i];
 972                 if ((ids->value.int_val & 0xffff) == device_id)
 973                         return ids->value.int_val;
 974         }
 975
 976         return 0;
 977 }
 978
 979 static int
 980 acpi_video_bus_get_one_device(struct acpi_device *device,
 981                               struct acpi_video_bus *video)
 982 {
 983         unsigned long long device_id;
 984         int status, device_type;
 985         struct acpi_video_device *data;
 986         struct acpi_video_device_attrib *attribute;
 987
 988         status =
 989             acpi_evaluate_integer(device->handle, "_ADR", NULL, &device_id);
 990         /* Some device omits _ADR, we skip them instead of fail */
 991         if (ACPI_FAILURE(status))
 992                 return 0;
 993
 994         data = kzalloc(sizeof(struct acpi_video_device), GFP_KERNEL);
 995         if (!data)
 996                 return -ENOMEM;
 997
 998         strcpy(acpi_device_name(device), ACPI_VIDEO_DEVICE_NAME);
 999         strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
1000         device->driver_data = data;
1001
1002         data->device_id = device_id;
1003         data->video = video;
1004         data->dev = device;
1005         INIT_DELAYED_WORK(&data->switch_brightness_work,
1006                           acpi_video_switch_brightness);
1007
1008         attribute = acpi_video_get_device_attr(video, device_id);
1009
1010         if (attribute && attribute->device_id_scheme) {
1011                 switch (attribute->display_type) {
1012                 case ACPI_VIDEO_DISPLAY_CRT:
1013                         data->flags.crt = 1;
1014                         break;
1015                 case ACPI_VIDEO_DISPLAY_TV:
1016                         data->flags.tvout = 1;
1017                         break;
1018                 case ACPI_VIDEO_DISPLAY_DVI:
1019                         data->flags.dvi = 1;
1020                         break;
1021                 case ACPI_VIDEO_DISPLAY_LCD:
1022                         data->flags.lcd = 1;
1023                         break;
1024                 default:
1025                         data->flags.unknown = 1;
1026                         break;
1027                 }
1028                 if (attribute->bios_can_detect)
1029                         data->flags.bios = 1;
1030         } else {
1031                 /* Check for legacy IDs */
1032                 device_type = acpi_video_get_device_type(video, device_id);
1033                 /* Ignore bits 16 and 18-20 */
1034                 switch (device_type & 0xffe2ffff) {
1035                 case ACPI_VIDEO_DISPLAY_LEGACY_MONITOR:
1036                         data->flags.crt = 1;
1037                         break;
1038                 case ACPI_VIDEO_DISPLAY_LEGACY_PANEL:
1039                         data->flags.lcd = 1;
1040                         break;
1041                 case ACPI_VIDEO_DISPLAY_LEGACY_TV:
1042                         data->flags.tvout = 1;
1043                         break;
1044                 default:
1045                         data->flags.unknown = 1;
1046                 }
1047         }
1048
1049         acpi_video_device_bind(video, data);
1050         acpi_video_device_find_cap(data);
1051
1052         mutex_lock(&video->device_list_lock);
1053         list_add_tail(&data->entry, &video->video_device_list);
1054         mutex_unlock(&video->device_list_lock);
1055
1056         return status;
1057 }
1058
1059 /*
1060  *  Arg:
1061  *      video   : video bus device
1062  *
1063  *  Return:
1064  *      none
1065  *
1066  *  Enumerate the video device list of the video bus,
1067  *  bind the ids with the corresponding video devices
1068  *  under the video bus.
1069  */
1070
1071 static void acpi_video_device_rebind(struct acpi_video_bus *video)
1072 {
1073         struct acpi_video_device *dev;
1074
1075         mutex_lock(&video->device_list_lock);
1076
1077         list_for_each_entry(dev, &video->video_device_list, entry)
1078                 acpi_video_device_bind(video, dev);
1079
1080         mutex_unlock(&video->device_list_lock);
1081 }
1082
1083 /*
1084  *  Arg:
1085  *      video   : video bus device
1086  *      device  : video output device under the video
1087  *              bus
1088  *
1089  *  Return:
1090  *      none
1091  *
1092  *  Bind the ids with the corresponding video devices
1093  *  under the video bus.
1094  */
1095
1096 static void
1097 acpi_video_device_bind(struct acpi_video_bus *video,
1098                        struct acpi_video_device *device)
1099 {
1100         struct acpi_video_enumerated_device *ids;
1101         int i;
1102
1103         for (i = 0; i < video->attached_count; i++) {
1104                 ids = &video->attached_array[i];
1105                 if (device->device_id == (ids->value.int_val & 0xffff)) {
1106                         ids->bind_info = device;
1107                         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "device_bind %d\n", i));
1108                 }
1109         }
1110 }
1111
1112 static bool acpi_video_device_in_dod(struct acpi_video_device *device)
1113 {
1114         struct acpi_video_bus *video = device->video;
1115         int i;
1116
1117         /*
1118          * If we have a broken _DOD or we have more than 8 output devices
1119          * under the graphics controller node that we can't proper deal with
1120          * in the operation region code currently, no need to test.
1121          */
1122         if (!video->attached_count || video->child_count > 8)
1123                 return true;
1124
1125         for (i = 0; i < video->attached_count; i++) {
1126                 if ((video->attached_array[i].value.int_val & 0xfff) ==
1127                     (device->device_id & 0xfff))
1128                         return true;
1129         }
1130
1131         return false;
1132 }
1133
1134 /*
1135  *  Arg:
1136  *      video   : video bus device
1137  *
1138  *  Return:
1139  *      < 0     : error
1140  *
1141  *  Call _DOD to enumerate all devices attached to display adapter
1142  *
1143  */
1144
1145 static int acpi_video_device_enumerate(struct acpi_video_bus *video)
1146 {
1147         int status;
1148         int count;
1149         int i;
1150         struct acpi_video_enumerated_device *active_list;
1151         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1152         union acpi_object *dod = NULL;
1153         union acpi_object *obj;
1154
1155         status = acpi_evaluate_object(video->device->handle, "_DOD", NULL, &buffer);
1156         if (!ACPI_SUCCESS(status)) {
1157                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _DOD"));
1158                 return status;
1159         }
1160
1161         dod = buffer.pointer;
1162         if (!dod || (dod->type != ACPI_TYPE_PACKAGE)) {
1163                 ACPI_EXCEPTION((AE_INFO, status, "Invalid _DOD data"));
1164                 status = -EFAULT;
1165                 goto out;
1166         }
1167
1168         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d video heads in _DOD\n",
1169                           dod->package.count));
1170
1171         active_list = kcalloc(1 + dod->package.count,
1172                               sizeof(struct acpi_video_enumerated_device),
1173                               GFP_KERNEL);
1174         if (!active_list) {
1175                 status = -ENOMEM;
1176                 goto out;
1177         }
1178
1179         count = 0;
1180         for (i = 0; i < dod->package.count; i++) {
1181                 obj = &dod->package.elements[i];
1182
1183                 if (obj->type != ACPI_TYPE_INTEGER) {
1184                         printk(KERN_ERR PREFIX
1185                                 "Invalid _DOD data in element %d\n", i);
1186                         continue;
1187                 }
1188
1189                 active_list[count].value.int_val = obj->integer.value;
1190                 active_list[count].bind_info = NULL;
1191                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "dod element[%d] = %d\n", i,
1192                                   (int)obj->integer.value));
1193                 count++;
1194         }
1195
1196         kfree(video->attached_array);
1197
1198         video->attached_array = active_list;
1199         video->attached_count = count;
1200
1201 out:
1202         kfree(buffer.pointer);
1203         return status;
1204 }
1205
1206 static int
1207 acpi_video_get_next_level(struct acpi_video_device *device,
1208                           u32 level_current, u32 event)
1209 {
1210         int min, max, min_above, max_below, i, l, delta = 255;
1211         max = max_below = 0;
1212         min = min_above = 255;
1213         /* Find closest level to level_current */
1214         for (i = 2; i < device->brightness->count; i++) {
1215                 l = device->brightness->levels[i];
1216                 if (abs(l - level_current) < abs(delta)) {
1217                         delta = l - level_current;
1218                         if (!delta)
1219                                 break;
1220                 }
1221         }
1222         /* Ajust level_current to closest available level */
1223         level_current += delta;
1224         for (i = 2; i < device->brightness->count; i++) {
1225                 l = device->brightness->levels[i];
1226                 if (l < min)
1227                         min = l;
1228                 if (l > max)
1229                         max = l;
1230                 if (l < min_above && l > level_current)
1231                         min_above = l;
1232                 if (l > max_below && l < level_current)
1233                         max_below = l;
1234         }
1235
1236         switch (event) {
1237         case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:
1238                 return (level_current < max) ? min_above : min;
1239         case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:
1240                 return (level_current < max) ? min_above : max;
1241         case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:
1242                 return (level_current > min) ? max_below : min;
1243         case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS:
1244         case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:
1245                 return 0;
1246         default:
1247                 return level_current;
1248         }
1249 }
1250
1251 static void
1252 acpi_video_switch_brightness(struct work_struct *work)
1253 {
1254         struct acpi_video_device *device = container_of(to_delayed_work(work),
1255                              struct acpi_video_device, switch_brightness_work);
1256         unsigned long long level_current, level_next;
1257         int event = device->switch_brightness_event;
1258         int result = -EINVAL;
1259
1260         /* no warning message if acpi_backlight=vendor or a quirk is used */
1261         if (!device->backlight)
1262                 return;
1263
1264         if (!device->brightness)
1265                 goto out;
1266
1267         result = acpi_video_device_lcd_get_level_current(device,
1268                                                          &level_current,
1269                                                          false);
1270         if (result)
1271                 goto out;
1272
1273         level_next = acpi_video_get_next_level(device, level_current, event);
1274
1275         result = acpi_video_device_lcd_set_level(device, level_next);
1276
1277         if (!result)
1278                 backlight_force_update(device->backlight,
1279                                        BACKLIGHT_UPDATE_HOTKEY);
1280
1281 out:
1282         if (result)
1283                 printk(KERN_ERR PREFIX "Failed to switch the brightness\n");
1284 }
1285
1286 int acpi_video_get_edid(struct acpi_device *device, int type, int device_id,
1287                         void **edid)
1288 {
1289         struct acpi_video_bus *video;
1290         struct acpi_video_device *video_device;
1291         union acpi_object *buffer = NULL;
1292         acpi_status status;
1293         int i, length;
1294
1295         if (!device || !acpi_driver_data(device))
1296                 return -EINVAL;
1297
1298         video = acpi_driver_data(device);
1299
1300         for (i = 0; i < video->attached_count; i++) {
1301                 video_device = video->attached_array[i].bind_info;
1302                 length = 256;
1303
1304                 if (!video_device)
1305                         continue;
1306
1307                 if (!video_device->cap._DDC)
1308                         continue;
1309
1310                 if (type) {
1311                         switch (type) {
1312                         case ACPI_VIDEO_DISPLAY_CRT:
1313                                 if (!video_device->flags.crt)
1314                                         continue;
1315                                 break;
1316                         case ACPI_VIDEO_DISPLAY_TV:
1317                                 if (!video_device->flags.tvout)
1318                                         continue;
1319                                 break;
1320                         case ACPI_VIDEO_DISPLAY_DVI:
1321                                 if (!video_device->flags.dvi)
1322                                         continue;
1323                                 break;
1324                         case ACPI_VIDEO_DISPLAY_LCD:
1325                                 if (!video_device->flags.lcd)
1326                                         continue;
1327                                 break;
1328                         }
1329                 } else if (video_device->device_id != device_id) {
1330                         continue;
1331                 }
1332
1333                 status = acpi_video_device_EDID(video_device, &buffer, length);
1334
1335                 if (ACPI_FAILURE(status) || !buffer ||
1336                     buffer->type != ACPI_TYPE_BUFFER) {
1337                         length = 128;
1338                         status = acpi_video_device_EDID(video_device, &buffer,
1339                                                         length);
1340                         if (ACPI_FAILURE(status) || !buffer ||
1341                             buffer->type != ACPI_TYPE_BUFFER) {
1342                                 continue;
1343                         }
1344                 }
1345
1346                 *edid = buffer->buffer.pointer;
1347                 return length;
1348         }
1349
1350         return -ENODEV;
1351 }
1352 EXPORT_SYMBOL(acpi_video_get_edid);
1353
1354 static int
1355 acpi_video_bus_get_devices(struct acpi_video_bus *video,
1356                            struct acpi_device *device)
1357 {
1358         int status = 0;
1359         struct acpi_device *dev;
1360
1361         /*
1362          * There are systems where video module known to work fine regardless
1363          * of broken _DOD and ignoring returned value here doesn't cause
1364          * any issues later.
1365          */
1366         acpi_video_device_enumerate(video);
1367
1368         list_for_each_entry(dev, &device->children, node) {
1369
1370                 status = acpi_video_bus_get_one_device(dev, video);
1371                 if (status) {
1372                         dev_err(&dev->dev, "Can't attach device\n");
1373                         break;
1374                 }
1375                 video->child_count++;
1376         }
1377         return status;
1378 }
1379
1380 /* acpi_video interface */
1381
1382 /*
1383  * Win8 requires setting bit2 of _DOS to let firmware know it shouldn't
1384  * preform any automatic brightness change on receiving a notification.
1385  */
1386 static int acpi_video_bus_start_devices(struct acpi_video_bus *video)
1387 {
1388         return acpi_video_bus_DOS(video, 0,
1389                                   acpi_osi_is_win8() ? 1 : 0);
1390 }
1391
1392 static int acpi_video_bus_stop_devices(struct acpi_video_bus *video)
1393 {
1394         return acpi_video_bus_DOS(video, 0,
1395                                   acpi_osi_is_win8() ? 0 : 1);
1396 }
1397
1398 static void acpi_video_bus_notify(struct acpi_device *device, u32 event)
1399 {
1400         struct acpi_video_bus *video = acpi_driver_data(device);
1401         struct input_dev *input;
1402         int keycode = 0;
1403
1404         if (!video || !video->input)
1405                 return;
1406
1407         input = video->input;
1408
1409         switch (event) {
1410         case ACPI_VIDEO_NOTIFY_SWITCH:  /* User requested a switch,
1411                                          * most likely via hotkey. */
1412                 keycode = KEY_SWITCHVIDEOMODE;
1413                 break;
1414
1415         case ACPI_VIDEO_NOTIFY_PROBE:   /* User plugged in or removed a video
1416                                          * connector. */
1417                 acpi_video_device_enumerate(video);
1418                 acpi_video_device_rebind(video);
1419                 keycode = KEY_SWITCHVIDEOMODE;
1420                 break;
1421
1422         case ACPI_VIDEO_NOTIFY_CYCLE:   /* Cycle Display output hotkey pressed. */
1423                 keycode = KEY_SWITCHVIDEOMODE;
1424                 break;
1425         case ACPI_VIDEO_NOTIFY_NEXT_OUTPUT:     /* Next Display output hotkey pressed. */
1426                 keycode = KEY_VIDEO_NEXT;
1427                 break;
1428         case ACPI_VIDEO_NOTIFY_PREV_OUTPUT:     /* previous Display output hotkey pressed. */
1429                 keycode = KEY_VIDEO_PREV;
1430                 break;
1431
1432         default:
1433                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1434                                   "Unsupported event [0x%x]\n", event));
1435                 break;
1436         }
1437
1438         if (acpi_notifier_call_chain(device, event, 0))
1439                 /* Something vetoed the keypress. */
1440                 keycode = 0;
1441
1442         if (keycode) {
1443                 input_report_key(input, keycode, 1);
1444                 input_sync(input);
1445                 input_report_key(input, keycode, 0);
1446                 input_sync(input);
1447         }
1448
1449         return;
1450 }
1451
1452 static void brightness_switch_event(struct acpi_video_device *video_device,
1453                                     u32 event)
1454 {
1455         if (!brightness_switch_enabled)
1456                 return;
1457
1458         video_device->switch_brightness_event = event;
1459         schedule_delayed_work(&video_device->switch_brightness_work, HZ / 10);
1460 }
1461
1462 static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data)
1463 {
1464         struct acpi_video_device *video_device = data;
1465         struct acpi_device *device = NULL;
1466         struct acpi_video_bus *bus;
1467         struct input_dev *input;
1468         int keycode = 0;
1469
1470         if (!video_device)
1471                 return;
1472
1473         device = video_device->dev;
1474         bus = video_device->video;
1475         input = bus->input;
1476
1477         switch (event) {
1478         case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:        /* Cycle brightness */
1479                 brightness_switch_event(video_device, event);
1480                 keycode = KEY_BRIGHTNESS_CYCLE;
1481                 break;
1482         case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:  /* Increase brightness */
1483                 brightness_switch_event(video_device, event);
1484                 keycode = KEY_BRIGHTNESSUP;
1485                 break;
1486         case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:  /* Decrease brightness */
1487                 brightness_switch_event(video_device, event);
1488                 keycode = KEY_BRIGHTNESSDOWN;
1489                 break;
1490         case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS: /* zero brightness */
1491                 brightness_switch_event(video_device, event);
1492                 keycode = KEY_BRIGHTNESS_ZERO;
1493                 break;
1494         case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:     /* display device off */
1495                 brightness_switch_event(video_device, event);
1496                 keycode = KEY_DISPLAY_OFF;
1497                 break;
1498         default:
1499                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1500                                   "Unsupported event [0x%x]\n", event));
1501                 break;
1502         }
1503
1504         acpi_notifier_call_chain(device, event, 0);
1505
1506         if (keycode) {
1507                 input_report_key(input, keycode, 1);
1508                 input_sync(input);
1509                 input_report_key(input, keycode, 0);
1510                 input_sync(input);
1511         }
1512
1513         return;
1514 }
1515
1516 static int acpi_video_resume(struct notifier_block *nb,
1517                                 unsigned long val, void *ign)
1518 {
1519         struct acpi_video_bus *video;
1520         struct acpi_video_device *video_device;
1521         int i;
1522
1523         switch (val) {
1524         case PM_HIBERNATION_PREPARE:
1525         case PM_SUSPEND_PREPARE:
1526         case PM_RESTORE_PREPARE:
1527                 return NOTIFY_DONE;
1528         }
1529
1530         video = container_of(nb, struct acpi_video_bus, pm_nb);
1531
1532         dev_info(&video->device->dev, "Restoring backlight state\n");
1533
1534         for (i = 0; i < video->attached_count; i++) {
1535                 video_device = video->attached_array[i].bind_info;
1536                 if (video_device && video_device->brightness)
1537                         acpi_video_device_lcd_set_level(video_device,
1538                                         video_device->brightness->curr);
1539         }
1540
1541         return NOTIFY_OK;
1542 }
1543
1544 static acpi_status
1545 acpi_video_bus_match(acpi_handle handle, u32 level, void *context,
1546                         void **return_value)
1547 {
1548         struct acpi_device *device = context;
1549         struct acpi_device *sibling;
1550         int result;
1551
1552         if (handle == device->handle)
1553                 return AE_CTRL_TERMINATE;
1554
1555         result = acpi_bus_get_device(handle, &sibling);
1556         if (result)
1557                 return AE_OK;
1558
1559         if (!strcmp(acpi_device_name(sibling), ACPI_VIDEO_BUS_NAME))
1560                         return AE_ALREADY_EXISTS;
1561
1562         return AE_OK;
1563 }
1564
1565 static void acpi_video_dev_register_backlight(struct acpi_video_device *device)
1566 {
1567         struct backlight_properties props;
1568         struct pci_dev *pdev;
1569         acpi_handle acpi_parent;
1570         struct device *parent = NULL;
1571         int result;
1572         static int count;
1573         char *name;
1574
1575         /*
1576          * Do not create backlight device for video output
1577          * device that is not in the enumerated list.
1578          */
1579         if (!acpi_video_device_in_dod(device)) {
1580                 dev_dbg(&device->dev->dev, "not in _DOD list, ignore\n");
1581                 return;
1582         }
1583
1584         result = acpi_video_init_brightness(device);
1585         if (result)
1586                 return;
1587
1588         if (disable_backlight_sysfs_if > 0)
1589                 return;
1590
1591         name = kasprintf(GFP_KERNEL, "acpi_video%d", count);
1592         if (!name)
1593                 return;
1594         count++;
1595
1596         acpi_get_parent(device->dev->handle, &acpi_parent);
1597
1598         pdev = acpi_get_pci_dev(acpi_parent);
1599         if (pdev) {
1600                 parent = &pdev->dev;
1601                 pci_dev_put(pdev);
1602         }
1603
1604         memset(&props, 0, sizeof(struct backlight_properties));
1605         props.type = BACKLIGHT_FIRMWARE;
1606         props.max_brightness = device->brightness->count - 3;
1607         device->backlight = backlight_device_register(name,
1608                                                       parent,
1609                                                       device,
1610                                                       &acpi_backlight_ops,
1611                                                       &props);
1612         kfree(name);
1613         if (IS_ERR(device->backlight)) {
1614                 device->backlight = NULL;
1615                 return;
1616         }
1617
1618         /*
1619          * Save current brightness level in case we have to restore it
1620          * before acpi_video_device_lcd_set_level() is called next time.
1621          */
1622         device->backlight->props.brightness =
1623                         acpi_video_get_brightness(device->backlight);
1624
1625         device->cooling_dev = thermal_cooling_device_register("LCD",
1626                                 device->dev, &video_cooling_ops);
1627         if (IS_ERR(device->cooling_dev)) {
1628                 /*
1629                  * Set cooling_dev to NULL so we don't crash trying to free it.
1630                  * Also, why the hell we are returning early and not attempt to
1631                  * register video output if cooling device registration failed?
1632                  * -- dtor
1633                  */
1634                 device->cooling_dev = NULL;
1635                 return;
1636         }
1637
1638         dev_info(&device->dev->dev, "registered as cooling_device%d\n",
1639                  device->cooling_dev->id);
1640         result = sysfs_create_link(&device->dev->dev.kobj,
1641                         &device->cooling_dev->device.kobj,
1642                         "thermal_cooling");
1643         if (result)
1644                 printk(KERN_ERR PREFIX "Create sysfs link\n");
1645         result = sysfs_create_link(&device->cooling_dev->device.kobj,
1646                         &device->dev->dev.kobj, "device");
1647         if (result)
1648                 printk(KERN_ERR PREFIX "Create sysfs link\n");
1649 }
1650
1651 static void acpi_video_run_bcl_for_osi(struct acpi_video_bus *video)
1652 {
1653         struct acpi_video_device *dev;
1654         union acpi_object *levels;
1655
1656         mutex_lock(&video->device_list_lock);
1657         list_for_each_entry(dev, &video->video_device_list, entry) {
1658                 if (!acpi_video_device_lcd_query_levels(dev, &levels))
1659                         kfree(levels);
1660         }
1661         mutex_unlock(&video->device_list_lock);
1662 }
1663
1664 static int acpi_video_bus_register_backlight(struct acpi_video_bus *video)
1665 {
1666         struct acpi_video_device *dev;
1667
1668         if (video->backlight_registered)
1669                 return 0;
1670
1671         acpi_video_run_bcl_for_osi(video);
1672
1673         if (acpi_video_get_backlight_type() != acpi_backlight_video)
1674                 return 0;
1675
1676         mutex_lock(&video->device_list_lock);
1677         list_for_each_entry(dev, &video->video_device_list, entry)
1678                 acpi_video_dev_register_backlight(dev);
1679         mutex_unlock(&video->device_list_lock);
1680
1681         video->backlight_registered = true;
1682
1683         video->pm_nb.notifier_call = acpi_video_resume;
1684         video->pm_nb.priority = 0;
1685         return register_pm_notifier(&video->pm_nb);
1686 }
1687
1688 static void acpi_video_dev_unregister_backlight(struct acpi_video_device *device)
1689 {
1690         if (device->backlight) {
1691                 backlight_device_unregister(device->backlight);
1692                 device->backlight = NULL;
1693         }
1694         if (device->brightness) {
1695                 kfree(device->brightness->levels);
1696                 kfree(device->brightness);
1697                 device->brightness = NULL;
1698         }
1699         if (device->cooling_dev) {
1700                 sysfs_remove_link(&device->dev->dev.kobj, "thermal_cooling");
1701                 sysfs_remove_link(&device->cooling_dev->device.kobj, "device");
1702                 thermal_cooling_device_unregister(device->cooling_dev);
1703                 device->cooling_dev = NULL;
1704         }
1705 }
1706
1707 static int acpi_video_bus_unregister_backlight(struct acpi_video_bus *video)
1708 {
1709         struct acpi_video_device *dev;
1710         int error;
1711
1712         if (!video->backlight_registered)
1713                 return 0;
1714
1715         error = unregister_pm_notifier(&video->pm_nb);
1716
1717         mutex_lock(&video->device_list_lock);
1718         list_for_each_entry(dev, &video->video_device_list, entry)
1719                 acpi_video_dev_unregister_backlight(dev);
1720         mutex_unlock(&video->device_list_lock);
1721
1722         video->backlight_registered = false;
1723
1724         return error;
1725 }
1726
1727 static void acpi_video_dev_add_notify_handler(struct acpi_video_device *device)
1728 {
1729         acpi_status status;
1730         struct acpi_device *adev = device->dev;
1731
1732         status = acpi_install_notify_handler(adev->handle, ACPI_DEVICE_NOTIFY,
1733                                              acpi_video_device_notify, device);
1734         if (ACPI_FAILURE(status))
1735                 dev_err(&adev->dev, "Error installing notify handler\n");
1736         else
1737                 device->flags.notify = 1;
1738 }
1739
1740 static int acpi_video_bus_add_notify_handler(struct acpi_video_bus *video)
1741 {
1742         struct input_dev *input;
1743         struct acpi_video_device *dev;
1744         int error;
1745
1746         video->input = input = input_allocate_device();
1747         if (!input) {
1748                 error = -ENOMEM;
1749                 goto out;
1750         }
1751
1752         error = acpi_video_bus_start_devices(video);
1753         if (error)
1754                 goto err_free_input;
1755
1756         snprintf(video->phys, sizeof(video->phys),
1757                         "%s/video/input0", acpi_device_hid(video->device));
1758
1759         input->name = acpi_device_name(video->device);
1760         input->phys = video->phys;
1761         input->id.bustype = BUS_HOST;
1762         input->id.product = 0x06;
1763         input->dev.parent = &video->device->dev;
1764         input->evbit[0] = BIT(EV_KEY);
1765         set_bit(KEY_SWITCHVIDEOMODE, input->keybit);
1766         set_bit(KEY_VIDEO_NEXT, input->keybit);
1767         set_bit(KEY_VIDEO_PREV, input->keybit);
1768         set_bit(KEY_BRIGHTNESS_CYCLE, input->keybit);
1769         set_bit(KEY_BRIGHTNESSUP, input->keybit);
1770         set_bit(KEY_BRIGHTNESSDOWN, input->keybit);
1771         set_bit(KEY_BRIGHTNESS_ZERO, input->keybit);
1772         set_bit(KEY_DISPLAY_OFF, input->keybit);
1773
1774         error = input_register_device(input);
1775         if (error)
1776                 goto err_stop_dev;
1777
1778         mutex_lock(&video->device_list_lock);
1779         list_for_each_entry(dev, &video->video_device_list, entry)
1780                 acpi_video_dev_add_notify_handler(dev);
1781         mutex_unlock(&video->device_list_lock);
1782
1783         return 0;
1784
1785 err_stop_dev:
1786         acpi_video_bus_stop_devices(video);
1787 err_free_input:
1788         input_free_device(input);
1789         video->input = NULL;
1790 out:
1791         return error;
1792 }
1793
1794 static void acpi_video_dev_remove_notify_handler(struct acpi_video_device *dev)
1795 {
1796         if (dev->flags.notify) {
1797                 acpi_remove_notify_handler(dev->dev->handle, ACPI_DEVICE_NOTIFY,
1798                                            acpi_video_device_notify);
1799                 dev->flags.notify = 0;
1800         }
1801 }
1802
1803 static void acpi_video_bus_remove_notify_handler(struct acpi_video_bus *video)
1804 {
1805         struct acpi_video_device *dev;
1806
1807         mutex_lock(&video->device_list_lock);
1808         list_for_each_entry(dev, &video->video_device_list, entry)
1809                 acpi_video_dev_remove_notify_handler(dev);
1810         mutex_unlock(&video->device_list_lock);
1811
1812         acpi_video_bus_stop_devices(video);
1813         input_unregister_device(video->input);
1814         video->input = NULL;
1815 }
1816
1817 static int acpi_video_bus_put_devices(struct acpi_video_bus *video)
1818 {
1819         struct acpi_video_device *dev, *next;
1820
1821         mutex_lock(&video->device_list_lock);
1822         list_for_each_entry_safe(dev, next, &video->video_device_list, entry) {
1823                 list_del(&dev->entry);
1824                 kfree(dev);
1825         }
1826         mutex_unlock(&video->device_list_lock);
1827
1828         return 0;
1829 }
1830
1831 static int instance;
1832
1833 static int acpi_video_bus_add(struct acpi_device *device)
1834 {
1835         struct acpi_video_bus *video;
1836         int error;
1837         acpi_status status;
1838
1839         status = acpi_walk_namespace(ACPI_TYPE_DEVICE,
1840                                 device->parent->handle, 1,
1841                                 acpi_video_bus_match, NULL,
1842                                 device, NULL);
1843         if (status == AE_ALREADY_EXISTS) {
1844                 printk(KERN_WARNING FW_BUG
1845                         "Duplicate ACPI video bus devices for the"
1846                         " same VGA controller, please try module "
1847                         "parameter \"video.allow_duplicates=1\""
1848                         "if the current driver doesn't work.\n");
1849                 if (!allow_duplicates)
1850                         return -ENODEV;
1851         }
1852
1853         video = kzalloc(sizeof(struct acpi_video_bus), GFP_KERNEL);
1854         if (!video)
1855                 return -ENOMEM;
1856
1857         /* a hack to fix the duplicate name "VID" problem on T61 */
1858         if (!strcmp(device->pnp.bus_id, "VID")) {
1859                 if (instance)
1860                         device->pnp.bus_id[3] = '0' + instance;
1861                 instance++;
1862         }
1863         /* a hack to fix the duplicate name "VGA" problem on Pa 3553 */
1864         if (!strcmp(device->pnp.bus_id, "VGA")) {
1865                 if (instance)
1866                         device->pnp.bus_id[3] = '0' + instance;
1867                 instance++;
1868         }
1869
1870         video->device = device;
1871         strcpy(acpi_device_name(device), ACPI_VIDEO_BUS_NAME);
1872         strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
1873         device->driver_data = video;
1874
1875         acpi_video_bus_find_cap(video);
1876         error = acpi_video_bus_check(video);
1877         if (error)
1878                 goto err_free_video;
1879
1880         mutex_init(&video->device_list_lock);
1881         INIT_LIST_HEAD(&video->video_device_list);
1882
1883         error = acpi_video_bus_get_devices(video, device);
1884         if (error)
1885                 goto err_put_video;
1886
1887         printk(KERN_INFO PREFIX "%s [%s] (multi-head: %s  rom: %s  post: %s)\n",
1888                ACPI_VIDEO_DEVICE_NAME, acpi_device_bid(device),
1889                video->flags.multihead ? "yes" : "no",
1890                video->flags.rom ? "yes" : "no",
1891                video->flags.post ? "yes" : "no");
1892         mutex_lock(&video_list_lock);
1893         list_add_tail(&video->entry, &video_bus_head);
1894         mutex_unlock(&video_list_lock);
1895
1896         acpi_video_bus_register_backlight(video);
1897         acpi_video_bus_add_notify_handler(video);
1898
1899         return 0;
1900
1901 err_put_video:
1902         acpi_video_bus_put_devices(video);
1903         kfree(video->attached_array);
1904 err_free_video:
1905         kfree(video);
1906         device->driver_data = NULL;
1907
1908         return error;
1909 }
1910
1911 static int acpi_video_bus_remove(struct acpi_device *device)
1912 {
1913         struct acpi_video_bus *video = NULL;
1914
1915
1916         if (!device || !acpi_driver_data(device))
1917                 return -EINVAL;
1918
1919         video = acpi_driver_data(device);
1920
1921         acpi_video_bus_remove_notify_handler(video);
1922         acpi_video_bus_unregister_backlight(video);
1923         acpi_video_bus_put_devices(video);
1924
1925         mutex_lock(&video_list_lock);
1926         list_del(&video->entry);
1927         mutex_unlock(&video_list_lock);
1928
1929         kfree(video->attached_array);
1930         kfree(video);
1931
1932         return 0;
1933 }
1934
1935 static int __init is_i740(struct pci_dev *dev)
1936 {
1937         if (dev->device == 0x00D1)
1938                 return 1;
1939         if (dev->device == 0x7000)
1940                 return 1;
1941         return 0;
1942 }
1943
1944 static int __init intel_opregion_present(void)
1945 {
1946         int opregion = 0;
1947         struct pci_dev *dev = NULL;
1948         u32 address;
1949
1950         for_each_pci_dev(dev) {
1951                 if ((dev->class >> 8) != PCI_CLASS_DISPLAY_VGA)
1952                         continue;
1953                 if (dev->vendor != PCI_VENDOR_ID_INTEL)
1954                         continue;
1955                 /* We don't want to poke around undefined i740 registers */
1956                 if (is_i740(dev))
1957                         continue;
1958                 pci_read_config_dword(dev, 0xfc, &address);
1959                 if (!address)
1960                         continue;
1961                 opregion = 1;
1962         }
1963         return opregion;
1964 }
1965
1966 int acpi_video_register(void)
1967 {
1968         int ret = 0;
1969
1970         mutex_lock(&register_count_mutex);
1971         if (register_count) {
1972                 /*
1973                  * if the function of acpi_video_register is already called,
1974                  * don't register the acpi_vide_bus again and return no error.
1975                  */
1976                 goto leave;
1977         }
1978
1979         mutex_init(&video_list_lock);
1980         INIT_LIST_HEAD(&video_bus_head);
1981
1982         dmi_check_system(video_dmi_table);
1983
1984         ret = acpi_bus_register_driver(&acpi_video_bus);
1985         if (ret)
1986                 goto leave;
1987
1988         /*
1989          * When the acpi_video_bus is loaded successfully, increase
1990          * the counter reference.
1991          */
1992         register_count = 1;
1993
1994 leave:
1995         mutex_unlock(&register_count_mutex);
1996         return ret;
1997 }
1998 EXPORT_SYMBOL(acpi_video_register);
1999
2000 void acpi_video_unregister(void)
2001 {
2002         mutex_lock(&register_count_mutex);
2003         if (register_count) {
2004                 acpi_bus_unregister_driver(&acpi_video_bus);
2005                 register_count = 0;
2006         }
2007         mutex_unlock(&register_count_mutex);
2008 }
2009 EXPORT_SYMBOL(acpi_video_unregister);
2010
2011 void acpi_video_unregister_backlight(void)
2012 {
2013         struct acpi_video_bus *video;
2014
2015         mutex_lock(&register_count_mutex);
2016         if (register_count) {
2017                 mutex_lock(&video_list_lock);
2018                 list_for_each_entry(video, &video_bus_head, entry)
2019                         acpi_video_bus_unregister_backlight(video);
2020                 mutex_unlock(&video_list_lock);
2021         }
2022         mutex_unlock(&register_count_mutex);
2023 }
2024
2025 /*
2026  * This is kind of nasty. Hardware using Intel chipsets may require
2027  * the video opregion code to be run first in order to initialise
2028  * state before any ACPI video calls are made. To handle this we defer
2029  * registration of the video class until the opregion code has run.
2030  */
2031
2032 static int __init acpi_video_init(void)
2033 {
2034         /*
2035          * Let the module load even if ACPI is disabled (e.g. due to
2036          * a broken BIOS) so that i915.ko can still be loaded on such
2037          * old systems without an AcpiOpRegion.
2038          *
2039          * acpi_video_register() will report -ENODEV later as well due
2040          * to acpi_disabled when i915.ko tries to register itself afterwards.
2041          */
2042         if (acpi_disabled)
2043                 return 0;
2044
2045         if (intel_opregion_present())
2046                 return 0;
2047
2048         return acpi_video_register();
2049 }
2050
2051 static void __exit acpi_video_exit(void)
2052 {
2053         acpi_video_detect_exit();
2054         acpi_video_unregister();
2055
2056         return;
2057 }
2058
2059 module_init(acpi_video_init);
2060 module_exit(acpi_video_exit);