acpi_video.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *  video.c - ACPI Video Driver
   4  *
   5  *  Copyright (C) 2004 Luming Yu <luming.yu@intel.com>
   6  *  Copyright (C) 2004 Bruno Ducrot <ducrot@poupinou.org>
   7  *  Copyright (C) 2006 Thomas Tuttle <linux-kernel@ttuttle.net>
   8  */
   9
  10 #include <linux/kernel.h>
  11 #include <linux/module.h>
  12 #include <linux/init.h>
  13 #include <linux/types.h>
  14 #include <linux/list.h>
  15 #include <linux/mutex.h>
  16 #include <linux/input.h>
  17 #include <linux/backlight.h>
  18 #include <linux/thermal.h>
  19 #include <linux/sort.h>
  20 #include <linux/pci.h>
  21 #include <linux/pci_ids.h>
  22 #include <linux/slab.h>
  23 #include <linux/dmi.h>
  24 #include <linux/suspend.h>
  25 #include <linux/acpi.h>
  26 #include <acpi/video.h>
  27 #include <linux/uaccess.h>
  28
  29 #define PREFIX "ACPI: "
  30
  31 #define ACPI_VIDEO_BUS_NAME             "Video Bus"
  32 #define ACPI_VIDEO_DEVICE_NAME          "Video Device"
  33
  34 #define MAX_NAME_LEN    20
  35
  36 #define _COMPONENT              ACPI_VIDEO_COMPONENT
  37 ACPI_MODULE_NAME("video");
  38
  39 MODULE_AUTHOR("Bruno Ducrot");
  40 MODULE_DESCRIPTION("ACPI Video Driver");
  41 MODULE_LICENSE("GPL");
  42
  43 static bool brightness_switch_enabled = true;
  44 module_param(brightness_switch_enabled, bool, 0644);
  45
  46 /*
  47  * By default, we don't allow duplicate ACPI video bus devices
  48  * under the same VGA controller
  49  */
  50 static bool allow_duplicates;
  51 module_param(allow_duplicates, bool, 0644);
  52
  53 static int disable_backlight_sysfs_if = -1;
  54 module_param(disable_backlight_sysfs_if, int, 0444);
  55
  56 #define REPORT_OUTPUT_KEY_EVENTS                0x01
  57 #define REPORT_BRIGHTNESS_KEY_EVENTS            0x02
  58 static int report_key_events = -1;
  59 module_param(report_key_events, int, 0644);
  60 MODULE_PARM_DESC(report_key_events,
  61         "0: none, 1: output changes, 2: brightness changes, 3: all");
  62
  63 static int hw_changes_brightness = -1;
  64 module_param(hw_changes_brightness, int, 0644);
  65 MODULE_PARM_DESC(hw_changes_brightness,
  66         "Set this to 1 on buggy hw which changes the brightness itself when "
  67         "a hotkey is pressed: -1: auto, 0: normal 1: hw-changes-brightness");
  68
  69 /*
  70  * Whether the struct acpi_video_device_attrib::device_id_scheme bit should be
  71  * assumed even if not actually set.
  72  */
  73 static bool device_id_scheme = false;
  74 module_param(device_id_scheme, bool, 0444);
  75
  76 static int only_lcd = -1;
  77 module_param(only_lcd, int, 0444);
  78
  79 static int register_count;
  80 static DEFINE_MUTEX(register_count_mutex);
  81 static DEFINE_MUTEX(video_list_lock);
  82 static LIST_HEAD(video_bus_head);
  83 static int acpi_video_bus_add(struct acpi_device *device);
  84 static int acpi_video_bus_remove(struct acpi_device *device);
  85 static void acpi_video_bus_notify(struct acpi_device *device, u32 event);
  86 void acpi_video_detect_exit(void);
  87
  88 /*
  89  * Indices in the _BCL method response: the first two items are special,
  90  * the rest are all supported levels.
  91  *
  92  * See page 575 of the ACPI spec 3.0
  93  */
  94 enum acpi_video_level_idx {
  95         ACPI_VIDEO_AC_LEVEL,            /* level when machine has full power */
  96         ACPI_VIDEO_BATTERY_LEVEL,       /* level when machine is on batteries */
  97         ACPI_VIDEO_FIRST_LEVEL,         /* actual supported levels begin here */
  98 };
  99
 100 static const struct acpi_device_id video_device_ids[] = {
 101         {ACPI_VIDEO_HID, 0},
 102         {"", 0},
 103 };
 104 MODULE_DEVICE_TABLE(acpi, video_device_ids);
 105
 106 static struct acpi_driver acpi_video_bus = {
 107         .name = "video",
 108         .class = ACPI_VIDEO_CLASS,
 109         .ids = video_device_ids,
 110         .ops = {
 111                 .add = acpi_video_bus_add,
 112                 .remove = acpi_video_bus_remove,
 113                 .notify = acpi_video_bus_notify,
 114                 },
 115 };
 116
 117 struct acpi_video_bus_flags {
 118         u8 multihead:1;         /* can switch video heads */
 119         u8 rom:1;               /* can retrieve a video rom */
 120         u8 post:1;              /* can configure the head to */
 121         u8 reserved:5;
 122 };
 123
 124 struct acpi_video_bus_cap {
 125         u8 _DOS:1;              /* Enable/Disable output switching */
 126         u8 _DOD:1;              /* Enumerate all devices attached to display adapter */
 127         u8 _ROM:1;              /* Get ROM Data */
 128         u8 _GPD:1;              /* Get POST Device */
 129         u8 _SPD:1;              /* Set POST Device */
 130         u8 _VPO:1;              /* Video POST Options */
 131         u8 reserved:2;
 132 };
 133
 134 struct acpi_video_device_attrib {
 135         u32 display_index:4;    /* A zero-based instance of the Display */
 136         u32 display_port_attachment:4;  /* This field differentiates the display type */
 137         u32 display_type:4;     /* Describe the specific type in use */
 138         u32 vendor_specific:4;  /* Chipset Vendor Specific */
 139         u32 bios_can_detect:1;  /* BIOS can detect the device */
 140         u32 depend_on_vga:1;    /* Non-VGA output device whose power is related to
 141                                    the VGA device. */
 142         u32 pipe_id:3;          /* For VGA multiple-head devices. */
 143         u32 reserved:10;        /* Must be 0 */
 144
 145         /*
 146          * The device ID might not actually follow the scheme described by this
 147          * struct acpi_video_device_attrib. If it does, then this bit
 148          * device_id_scheme is set; otherwise, other fields should be ignored.
 149          *
 150          * (but also see the global flag device_id_scheme)
 151          */
 152         u32 device_id_scheme:1;
 153 };
 154
 155 struct acpi_video_enumerated_device {
 156         union {
 157                 u32 int_val;
 158                 struct acpi_video_device_attrib attrib;
 159         } value;
 160         struct acpi_video_device *bind_info;
 161 };
 162
 163 struct acpi_video_bus {
 164         struct acpi_device *device;
 165         bool backlight_registered;
 166         u8 dos_setting;
 167         struct acpi_video_enumerated_device *attached_array;
 168         u8 attached_count;
 169         u8 child_count;
 170         struct acpi_video_bus_cap cap;
 171         struct acpi_video_bus_flags flags;
 172         struct list_head video_device_list;
 173         struct mutex device_list_lock;  /* protects video_device_list */
 174         struct list_head entry;
 175         struct input_dev *input;
 176         char phys[32];  /* for input device */
 177         struct notifier_block pm_nb;
 178 };
 179
 180 struct acpi_video_device_flags {
 181         u8 crt:1;
 182         u8 lcd:1;
 183         u8 tvout:1;
 184         u8 dvi:1;
 185         u8 bios:1;
 186         u8 unknown:1;
 187         u8 notify:1;
 188         u8 reserved:1;
 189 };
 190
 191 struct acpi_video_device_cap {
 192         u8 _ADR:1;              /* Return the unique ID */
 193         u8 _BCL:1;              /* Query list of brightness control levels supported */
 194         u8 _BCM:1;              /* Set the brightness level */
 195         u8 _BQC:1;              /* Get current brightness level */
 196         u8 _BCQ:1;              /* Some buggy BIOS uses _BCQ instead of _BQC */
 197         u8 _DDC:1;              /* Return the EDID for this device */
 198 };
 199
 200 struct acpi_video_device {
 201         unsigned long device_id;
 202         struct acpi_video_device_flags flags;
 203         struct acpi_video_device_cap cap;
 204         struct list_head entry;
 205         struct delayed_work switch_brightness_work;
 206         int switch_brightness_event;
 207         struct acpi_video_bus *video;
 208         struct acpi_device *dev;
 209         struct acpi_video_device_brightness *brightness;
 210         struct backlight_device *backlight;
 211         struct thermal_cooling_device *cooling_dev;
 212 };
 213
 214 static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data);
 215 static void acpi_video_device_rebind(struct acpi_video_bus *video);
 216 static void acpi_video_device_bind(struct acpi_video_bus *video,
 217                                    struct acpi_video_device *device);
 218 static int acpi_video_device_enumerate(struct acpi_video_bus *video);
 219 static int acpi_video_device_lcd_set_level(struct acpi_video_device *device,
 220                         int level);
 221 static int acpi_video_device_lcd_get_level_current(
 222                         struct acpi_video_device *device,
 223                         unsigned long long *level, bool raw);
 224 static int acpi_video_get_next_level(struct acpi_video_device *device,
 225                                      u32 level_current, u32 event);
 226 static void acpi_video_switch_brightness(struct work_struct *work);
 227
 228 /* backlight device sysfs support */
 229 static int acpi_video_get_brightness(struct backlight_device *bd)
 230 {
 231         unsigned long long cur_level;
 232         int i;
 233         struct acpi_video_device *vd = bl_get_data(bd);
 234
 235         if (acpi_video_device_lcd_get_level_current(vd, &cur_level, false))
 236                 return -EINVAL;
 237         for (i = ACPI_VIDEO_FIRST_LEVEL; i < vd->brightness->count; i++) {
 238                 if (vd->brightness->levels[i] == cur_level)
 239                         return i - ACPI_VIDEO_FIRST_LEVEL;
 240         }
 241         return 0;
 242 }
 243
 244 static int acpi_video_set_brightness(struct backlight_device *bd)
 245 {
 246         int request_level = bd->props.brightness + ACPI_VIDEO_FIRST_LEVEL;
 247         struct acpi_video_device *vd = bl_get_data(bd);
 248
 249         cancel_delayed_work(&vd->switch_brightness_work);
 250         return acpi_video_device_lcd_set_level(vd,
 251                                 vd->brightness->levels[request_level]);
 252 }
 253
 254 static const struct backlight_ops acpi_backlight_ops = {
 255         .get_brightness = acpi_video_get_brightness,
 256         .update_status  = acpi_video_set_brightness,
 257 };
 258
 259 /* thermal cooling device callbacks */
 260 static int video_get_max_state(struct thermal_cooling_device *cooling_dev,
 261                                unsigned long *state)
 262 {
 263         struct acpi_device *device = cooling_dev->devdata;
 264         struct acpi_video_device *video = acpi_driver_data(device);
 265
 266         *state = video->brightness->count - ACPI_VIDEO_FIRST_LEVEL - 1;
 267         return 0;
 268 }
 269
 270 static int video_get_cur_state(struct thermal_cooling_device *cooling_dev,
 271                                unsigned long *state)
 272 {
 273         struct acpi_device *device = cooling_dev->devdata;
 274         struct acpi_video_device *video = acpi_driver_data(device);
 275         unsigned long long level;
 276         int offset;
 277
 278         if (acpi_video_device_lcd_get_level_current(video, &level, false))
 279                 return -EINVAL;
 280         for (offset = ACPI_VIDEO_FIRST_LEVEL; offset < video->brightness->count;
 281              offset++)
 282                 if (level == video->brightness->levels[offset]) {
 283                         *state = video->brightness->count - offset - 1;
 284                         return 0;
 285                 }
 286
 287         return -EINVAL;
 288 }
 289
 290 static int
 291 video_set_cur_state(struct thermal_cooling_device *cooling_dev, unsigned long state)
 292 {
 293         struct acpi_device *device = cooling_dev->devdata;
 294         struct acpi_video_device *video = acpi_driver_data(device);
 295         int level;
 296
 297         if (state >= video->brightness->count - ACPI_VIDEO_FIRST_LEVEL)
 298                 return -EINVAL;
 299
 300         state = video->brightness->count - state;
 301         level = video->brightness->levels[state - 1];
 302         return acpi_video_device_lcd_set_level(video, level);
 303 }
 304
 305 static const struct thermal_cooling_device_ops video_cooling_ops = {
 306         .get_max_state = video_get_max_state,
 307         .get_cur_state = video_get_cur_state,
 308         .set_cur_state = video_set_cur_state,
 309 };
 310
 311 /*
 312  * --------------------------------------------------------------------------
 313  *                             Video Management
 314  * --------------------------------------------------------------------------
 315  */
 316
 317 static int
 318 acpi_video_device_lcd_query_levels(acpi_handle handle,
 319                                    union acpi_object **levels)
 320 {
 321         int status;
 322         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 323         union acpi_object *obj;
 324
 325
 326         *levels = NULL;
 327
 328         status = acpi_evaluate_object(handle, "_BCL", NULL, &buffer);
 329         if (!ACPI_SUCCESS(status))
 330                 return status;
 331         obj = (union acpi_object *)buffer.pointer;
 332         if (!obj || (obj->type != ACPI_TYPE_PACKAGE)) {
 333                 printk(KERN_ERR PREFIX "Invalid _BCL data\n");
 334                 status = -EFAULT;
 335                 goto err;
 336         }
 337
 338         *levels = obj;
 339
 340         return 0;
 341
 342 err:
 343         kfree(buffer.pointer);
 344
 345         return status;
 346 }
 347
 348 static int
 349 acpi_video_device_lcd_set_level(struct acpi_video_device *device, int level)
 350 {
 351         int status;
 352         int state;
 353
 354         status = acpi_execute_simple_method(device->dev->handle,
 355                                             "_BCM", level);
 356         if (ACPI_FAILURE(status)) {
 357                 ACPI_ERROR((AE_INFO, "Evaluating _BCM failed"));
 358                 return -EIO;
 359         }
 360
 361         device->brightness->curr = level;
 362         for (state = ACPI_VIDEO_FIRST_LEVEL; state < device->brightness->count;
 363              state++)
 364                 if (level == device->brightness->levels[state]) {
 365                         if (device->backlight)
 366                                 device->backlight->props.brightness =
 367                                         state - ACPI_VIDEO_FIRST_LEVEL;
 368                         return 0;
 369                 }
 370
 371         ACPI_ERROR((AE_INFO, "Current brightness invalid"));
 372         return -EINVAL;
 373 }
 374
 375 /*
 376  * For some buggy _BQC methods, we need to add a constant value to
 377  * the _BQC return value to get the actual current brightness level
 378  */
 379
 380 static int bqc_offset_aml_bug_workaround;
 381 static int video_set_bqc_offset(const struct dmi_system_id *d)
 382 {
 383         bqc_offset_aml_bug_workaround = 9;
 384         return 0;
 385 }
 386
 387 static int video_disable_backlight_sysfs_if(
 388         const struct dmi_system_id *d)
 389 {
 390         if (disable_backlight_sysfs_if == -1)
 391                 disable_backlight_sysfs_if = 1;
 392         return 0;
 393 }
 394
 395 static int video_set_device_id_scheme(const struct dmi_system_id *d)
 396 {
 397         device_id_scheme = true;
 398         return 0;
 399 }
 400
 401 static int video_enable_only_lcd(const struct dmi_system_id *d)
 402 {
 403         only_lcd = true;
 404         return 0;
 405 }
 406
 407 static int video_set_report_key_events(const struct dmi_system_id *id)
 408 {
 409         if (report_key_events == -1)
 410                 report_key_events = (uintptr_t)id->driver_data;
 411         return 0;
 412 }
 413
 414 static int video_hw_changes_brightness(
 415         const struct dmi_system_id *d)
 416 {
 417         if (hw_changes_brightness == -1)
 418                 hw_changes_brightness = 1;
 419         return 0;
 420 }
 421
 422 static const struct dmi_system_id video_dmi_table[] = {
 423         /*
 424          * Broken _BQC workaround http://bugzilla.kernel.org/show_bug.cgi?id=13121
 425          */
 426         {
 427          .callback = video_set_bqc_offset,
 428          .ident = "Acer Aspire 5720",
 429          .matches = {
 430                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
 431                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5720"),
 432                 },
 433         },
 434         {
 435          .callback = video_set_bqc_offset,
 436          .ident = "Acer Aspire 5710Z",
 437          .matches = {
 438                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
 439                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5710Z"),
 440                 },
 441         },
 442         {
 443          .callback = video_set_bqc_offset,
 444          .ident = "eMachines E510",
 445          .matches = {
 446                 DMI_MATCH(DMI_BOARD_VENDOR, "EMACHINES"),
 447                 DMI_MATCH(DMI_PRODUCT_NAME, "eMachines E510"),
 448                 },
 449         },
 450         {
 451          .callback = video_set_bqc_offset,
 452          .ident = "Acer Aspire 5315",
 453          .matches = {
 454                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
 455                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5315"),
 456                 },
 457         },
 458         {
 459          .callback = video_set_bqc_offset,
 460          .ident = "Acer Aspire 7720",
 461          .matches = {
 462                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
 463                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 7720"),
 464                 },
 465         },
 466
 467         /*
 468          * Some machines have a broken acpi-video interface for brightness
 469          * control, but still need an acpi_video_device_lcd_set_level() call
 470          * on resume to turn the backlight power on.  We Enable backlight
 471          * control on these systems, but do not register a backlight sysfs
 472          * as brightness control does not work.
 473          */
 474         {
 475          /* https://bugzilla.kernel.org/show_bug.cgi?id=21012 */
 476          .callback = video_disable_backlight_sysfs_if,
 477          .ident = "Toshiba Portege R700",
 478          .matches = {
 479                 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
 480                 DMI_MATCH(DMI_PRODUCT_NAME, "PORTEGE R700"),
 481                 },
 482         },
 483         {
 484          /* https://bugs.freedesktop.org/show_bug.cgi?id=82634 */
 485          .callback = video_disable_backlight_sysfs_if,
 486          .ident = "Toshiba Portege R830",
 487          .matches = {
 488                 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
 489                 DMI_MATCH(DMI_PRODUCT_NAME, "PORTEGE R830"),
 490                 },
 491         },
 492         {
 493          /* https://bugzilla.kernel.org/show_bug.cgi?id=21012 */
 494          .callback = video_disable_backlight_sysfs_if,
 495          .ident = "Toshiba Satellite R830",
 496          .matches = {
 497                 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
 498                 DMI_MATCH(DMI_PRODUCT_NAME, "SATELLITE R830"),
 499                 },
 500         },
 501         {
 502          .callback = video_disable_backlight_sysfs_if,
 503          .ident = "Toshiba Satellite Z830",
 504          .matches = {
 505                 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
 506                 DMI_MATCH(DMI_PRODUCT_NAME, "SATELLITE Z830"),
 507                 },
 508         },
 509         {
 510          .callback = video_disable_backlight_sysfs_if,
 511          .ident = "Toshiba Portege Z830",
 512          .matches = {
 513                 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
 514                 DMI_MATCH(DMI_PRODUCT_NAME, "PORTEGE Z830"),
 515                 },
 516         },
 517         /*
 518          * Some machine's _DOD IDs don't have bit 31(Device ID Scheme) set
 519          * but the IDs actually follow the Device ID Scheme.
 520          */
 521         {
 522          /* https://bugzilla.kernel.org/show_bug.cgi?id=104121 */
 523          .callback = video_set_device_id_scheme,
 524          .ident = "ESPRIMO Mobile M9410",
 525          .matches = {
 526                 DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU SIEMENS"),
 527                 DMI_MATCH(DMI_PRODUCT_NAME, "ESPRIMO Mobile M9410"),
 528                 },
 529         },
 530         /*
 531          * Some machines have multiple video output devices, but only the one
 532          * that is the type of LCD can do the backlight control so we should not
 533          * register backlight interface for other video output devices.
 534          */
 535         {
 536          /* https://bugzilla.kernel.org/show_bug.cgi?id=104121 */
 537          .callback = video_enable_only_lcd,
 538          .ident = "ESPRIMO Mobile M9410",
 539          .matches = {
 540                 DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU SIEMENS"),
 541                 DMI_MATCH(DMI_PRODUCT_NAME, "ESPRIMO Mobile M9410"),
 542                 },
 543         },
 544         /*
 545          * Some machines report wrong key events on the acpi-bus, suppress
 546          * key event reporting on these.  Note this is only intended to work
 547          * around events which are plain wrong. In some cases we get double
 548          * events, in this case acpi-video is considered the canonical source
 549          * and the events from the other source should be filtered. E.g.
 550          * by calling acpi_video_handles_brightness_key_presses() from the
 551          * vendor acpi/wmi driver or by using /lib/udev/hwdb.d/60-keyboard.hwdb
 552          */
 553         {
 554          .callback = video_set_report_key_events,
 555          .driver_data = (void *)((uintptr_t)REPORT_OUTPUT_KEY_EVENTS),
 556          .ident = "Dell Vostro V131",
 557          .matches = {
 558                 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 559                 DMI_MATCH(DMI_PRODUCT_NAME, "Vostro V131"),
 560                 },
 561         },
 562         {
 563          .callback = video_set_report_key_events,
 564          .driver_data = (void *)((uintptr_t)REPORT_BRIGHTNESS_KEY_EVENTS),
 565          .ident = "Dell Vostro 3350",
 566          .matches = {
 567                 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 568                 DMI_MATCH(DMI_PRODUCT_NAME, "Vostro 3350"),
 569                 },
 570         },
 571         /*
 572          * Some machines change the brightness themselves when a brightness
 573          * hotkey gets pressed, despite us telling them not to. In this case
 574          * acpi_video_device_notify() should only call backlight_force_update(
 575          * BACKLIGHT_UPDATE_HOTKEY) and not do anything else.
 576          */
 577         {
 578          /* https://bugzilla.kernel.org/show_bug.cgi?id=204077 */
 579          .callback = video_hw_changes_brightness,
 580          .ident = "Packard Bell EasyNote MZ35",
 581          .matches = {
 582                 DMI_MATCH(DMI_SYS_VENDOR, "Packard Bell"),
 583                 DMI_MATCH(DMI_PRODUCT_NAME, "EasyNote MZ35"),
 584                 },
 585         },
 586         {}
 587 };
 588
 589 static unsigned long long
 590 acpi_video_bqc_value_to_level(struct acpi_video_device *device,
 591                               unsigned long long bqc_value)
 592 {
 593         unsigned long long level;
 594
 595         if (device->brightness->flags._BQC_use_index) {
 596                 /*
 597                  * _BQC returns an index that doesn't account for the first 2
 598                  * items with special meaning (see enum acpi_video_level_idx),
 599                  * so we need to compensate for that by offsetting ourselves
 600                  */
 601                 if (device->brightness->flags._BCL_reversed)
 602                         bqc_value = device->brightness->count -
 603                                 ACPI_VIDEO_FIRST_LEVEL - 1 - bqc_value;
 604
 605                 level = device->brightness->levels[bqc_value +
 606                                                    ACPI_VIDEO_FIRST_LEVEL];
 607         } else {
 608                 level = bqc_value;
 609         }
 610
 611         level += bqc_offset_aml_bug_workaround;
 612
 613         return level;
 614 }
 615
 616 static int
 617 acpi_video_device_lcd_get_level_current(struct acpi_video_device *device,
 618                                         unsigned long long *level, bool raw)
 619 {
 620         acpi_status status = AE_OK;
 621         int i;
 622
 623         if (device->cap._BQC || device->cap._BCQ) {
 624                 char *buf = device->cap._BQC ? "_BQC" : "_BCQ";
 625
 626                 status = acpi_evaluate_integer(device->dev->handle, buf,
 627                                                 NULL, level);
 628                 if (ACPI_SUCCESS(status)) {
 629                         if (raw) {
 630                                 /*
 631                                  * Caller has indicated he wants the raw
 632                                  * value returned by _BQC, so don't furtherly
 633                                  * mess with the value.
 634                                  */
 635                                 return 0;
 636                         }
 637
 638                         *level = acpi_video_bqc_value_to_level(device, *level);
 639
 640                         for (i = ACPI_VIDEO_FIRST_LEVEL;
 641                              i < device->brightness->count; i++)
 642                                 if (device->brightness->levels[i] == *level) {
 643                                         device->brightness->curr = *level;
 644                                         return 0;
 645                                 }
 646                         /*
 647                          * BQC returned an invalid level.
 648                          * Stop using it.
 649                          */
 650                         ACPI_WARNING((AE_INFO,
 651                                       "%s returned an invalid level",
 652                                       buf));
 653                         device->cap._BQC = device->cap._BCQ = 0;
 654                 } else {
 655                         /*
 656                          * Fixme:
 657                          * should we return an error or ignore this failure?
 658                          * dev->brightness->curr is a cached value which stores
 659                          * the correct current backlight level in most cases.
 660                          * ACPI video backlight still works w/ buggy _BQC.
 661                          * http://bugzilla.kernel.org/show_bug.cgi?id=12233
 662                          */
 663                         ACPI_WARNING((AE_INFO, "Evaluating %s failed", buf));
 664                         device->cap._BQC = device->cap._BCQ = 0;
 665                 }
 666         }
 667
 668         *level = device->brightness->curr;
 669         return 0;
 670 }
 671
 672 static int
 673 acpi_video_device_EDID(struct acpi_video_device *device,
 674                        union acpi_object **edid, ssize_t length)
 675 {
 676         int status;
 677         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 678         union acpi_object *obj;
 679         union acpi_object arg0 = { ACPI_TYPE_INTEGER };
 680         struct acpi_object_list args = { 1, &arg0 };
 681
 682
 683         *edid = NULL;
 684
 685         if (!device)
 686                 return -ENODEV;
 687         if (length == 128)
 688                 arg0.integer.value = 1;
 689         else if (length == 256)
 690                 arg0.integer.value = 2;
 691         else
 692                 return -EINVAL;
 693
 694         status = acpi_evaluate_object(device->dev->handle, "_DDC", &args, &buffer);
 695         if (ACPI_FAILURE(status))
 696                 return -ENODEV;
 697
 698         obj = buffer.pointer;
 699
 700         if (obj && obj->type == ACPI_TYPE_BUFFER)
 701                 *edid = obj;
 702         else {
 703                 printk(KERN_ERR PREFIX "Invalid _DDC data\n");
 704                 status = -EFAULT;
 705                 kfree(obj);
 706         }
 707
 708         return status;
 709 }
 710
 711 /* bus */
 712
 713 /*
 714  *  Arg:
 715  *      video           : video bus device pointer
 716  *      bios_flag       :
 717  *              0.      The system BIOS should NOT automatically switch(toggle)
 718  *                      the active display output.
 719  *              1.      The system BIOS should automatically switch (toggle) the
 720  *                      active display output. No switch event.
 721  *              2.      The _DGS value should be locked.
 722  *              3.      The system BIOS should not automatically switch (toggle) the
 723  *                      active display output, but instead generate the display switch
 724  *                      event notify code.
 725  *      lcd_flag        :
 726  *              0.      The system BIOS should automatically control the brightness level
 727  *                      of the LCD when:
 728  *                      - the power changes from AC to DC (ACPI appendix B)
 729  *                      - a brightness hotkey gets pressed (implied by Win7/8 backlight docs)
 730  *              1.      The system BIOS should NOT automatically control the brightness
 731  *                      level of the LCD when:
 732  *                      - the power changes from AC to DC (ACPI appendix B)
 733  *                      - a brightness hotkey gets pressed (implied by Win7/8 backlight docs)
 734  *  Return Value:
 735  *              -EINVAL wrong arg.
 736  */
 737
 738 static int
 739 acpi_video_bus_DOS(struct acpi_video_bus *video, int bios_flag, int lcd_flag)
 740 {
 741         acpi_status status;
 742
 743         if (!video->cap._DOS)
 744                 return 0;
 745
 746         if (bios_flag < 0 || bios_flag > 3 || lcd_flag < 0 || lcd_flag > 1)
 747                 return -EINVAL;
 748         video->dos_setting = (lcd_flag << 2) | bios_flag;
 749         status = acpi_execute_simple_method(video->device->handle, "_DOS",
 750                                             (lcd_flag << 2) | bios_flag);
 751         if (ACPI_FAILURE(status))
 752                 return -EIO;
 753
 754         return 0;
 755 }
 756
 757 /*
 758  * Simple comparison function used to sort backlight levels.
 759  */
 760
 761 static int
 762 acpi_video_cmp_level(const void *a, const void *b)
 763 {
 764         return *(int *)a - *(int *)b;
 765 }
 766
 767 /*
 768  * Decides if _BQC/_BCQ for this system is usable
 769  *
 770  * We do this by changing the level first and then read out the current
 771  * brightness level, if the value does not match, find out if it is using
 772  * index. If not, clear the _BQC/_BCQ capability.
 773  */
 774 static int acpi_video_bqc_quirk(struct acpi_video_device *device,
 775                                 int max_level, int current_level)
 776 {
 777         struct acpi_video_device_brightness *br = device->brightness;
 778         int result;
 779         unsigned long long level;
 780         int test_level;
 781
 782         /* don't mess with existing known broken systems */
 783         if (bqc_offset_aml_bug_workaround)
 784                 return 0;
 785
 786         /*
 787          * Some systems always report current brightness level as maximum
 788          * through _BQC, we need to test another value for them. However,
 789          * there is a subtlety:
 790          *
 791          * If the _BCL package ordering is descending, the first level
 792          * (br->levels[2]) is likely to be 0, and if the number of levels
 793          * matches the number of steps, we might confuse a returned level to
 794          * mean the index.
 795          *
 796          * For example:
 797          *
 798          *     current_level = max_level = 100
 799          *     test_level = 0
 800          *     returned level = 100
 801          *
 802          * In this case 100 means the level, not the index, and _BCM failed.
 803          * Still, if the _BCL package ordering is descending, the index of
 804          * level 0 is also 100, so we assume _BQC is indexed, when it's not.
 805          *
 806          * This causes all _BQC calls to return bogus values causing weird
 807          * behavior from the user's perspective.  For example:
 808          *
 809          * xbacklight -set 10; xbacklight -set 20;
 810          *
 811          * would flash to 90% and then slowly down to the desired level (20).
 812          *
 813          * The solution is simple; test anything other than the first level
 814          * (e.g. 1).
 815          */
 816         test_level = current_level == max_level
 817                 ? br->levels[ACPI_VIDEO_FIRST_LEVEL + 1]
 818                 : max_level;
 819
 820         result = acpi_video_device_lcd_set_level(device, test_level);
 821         if (result)
 822                 return result;
 823
 824         result = acpi_video_device_lcd_get_level_current(device, &level, true);
 825         if (result)
 826                 return result;
 827
 828         if (level != test_level) {
 829                 /* buggy _BQC found, need to find out if it uses index */
 830                 if (level < br->count) {
 831                         if (br->flags._BCL_reversed)
 832                                 level = br->count - ACPI_VIDEO_FIRST_LEVEL - 1 - level;
 833                         if (br->levels[level + ACPI_VIDEO_FIRST_LEVEL] == test_level)
 834                                 br->flags._BQC_use_index = 1;
 835                 }
 836
 837                 if (!br->flags._BQC_use_index)
 838                         device->cap._BQC = device->cap._BCQ = 0;
 839         }
 840
 841         return 0;
 842 }
 843
 844 int acpi_video_get_levels(struct acpi_device *device,
 845                           struct acpi_video_device_brightness **dev_br,
 846                           int *pmax_level)
 847 {
 848         union acpi_object *obj = NULL;
 849         int i, max_level = 0, count = 0, level_ac_battery = 0;
 850         union acpi_object *o;
 851         struct acpi_video_device_brightness *br = NULL;
 852         int result = 0;
 853         u32 value;
 854
 855         if (!ACPI_SUCCESS(acpi_video_device_lcd_query_levels(device->handle,
 856                                                                 &obj))) {
 857                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Could not query available "
 858                                                 "LCD brightness level\n"));
 859                 result = -ENODEV;
 860                 goto out;
 861         }
 862
 863         if (obj->package.count < ACPI_VIDEO_FIRST_LEVEL) {
 864                 result = -EINVAL;
 865                 goto out;
 866         }
 867
 868         br = kzalloc(sizeof(*br), GFP_KERNEL);
 869         if (!br) {
 870                 printk(KERN_ERR "can't allocate memory\n");
 871                 result = -ENOMEM;
 872                 goto out;
 873         }
 874
 875         /*
 876          * Note that we have to reserve 2 extra items (ACPI_VIDEO_FIRST_LEVEL),
 877          * in order to account for buggy BIOS which don't export the first two
 878          * special levels (see below)
 879          */
 880         br->levels = kmalloc_array(obj->package.count + ACPI_VIDEO_FIRST_LEVEL,
 881                                    sizeof(*br->levels),
 882                                    GFP_KERNEL);
 883         if (!br->levels) {
 884                 result = -ENOMEM;
 885                 goto out_free;
 886         }
 887
 888         for (i = 0; i < obj->package.count; i++) {
 889                 o = (union acpi_object *)&obj->package.elements[i];
 890                 if (o->type != ACPI_TYPE_INTEGER) {
 891                         printk(KERN_ERR PREFIX "Invalid data\n");
 892                         continue;
 893                 }
 894                 value = (u32) o->integer.value;
 895                 /* Skip duplicate entries */
 896                 if (count > ACPI_VIDEO_FIRST_LEVEL
 897                     && br->levels[count - 1] == value)
 898                         continue;
 899
 900                 br->levels[count] = value;
 901
 902                 if (br->levels[count] > max_level)
 903                         max_level = br->levels[count];
 904                 count++;
 905         }
 906
 907         /*
 908          * some buggy BIOS don't export the levels
 909          * when machine is on AC/Battery in _BCL package.
 910          * In this case, the first two elements in _BCL packages
 911          * are also supported brightness levels that OS should take care of.
 912          */
 913         for (i = ACPI_VIDEO_FIRST_LEVEL; i < count; i++) {
 914                 if (br->levels[i] == br->levels[ACPI_VIDEO_AC_LEVEL])
 915                         level_ac_battery++;
 916                 if (br->levels[i] == br->levels[ACPI_VIDEO_BATTERY_LEVEL])
 917                         level_ac_battery++;
 918         }
 919
 920         if (level_ac_battery < ACPI_VIDEO_FIRST_LEVEL) {
 921                 level_ac_battery = ACPI_VIDEO_FIRST_LEVEL - level_ac_battery;
 922                 br->flags._BCL_no_ac_battery_levels = 1;
 923                 for (i = (count - 1 + level_ac_battery);
 924                      i >= ACPI_VIDEO_FIRST_LEVEL; i--)
 925                         br->levels[i] = br->levels[i - level_ac_battery];
 926                 count += level_ac_battery;
 927         } else if (level_ac_battery > ACPI_VIDEO_FIRST_LEVEL)
 928                 ACPI_ERROR((AE_INFO, "Too many duplicates in _BCL package"));
 929
 930         /* Check if the _BCL package is in a reversed order */
 931         if (max_level == br->levels[ACPI_VIDEO_FIRST_LEVEL]) {
 932                 br->flags._BCL_reversed = 1;
 933                 sort(&br->levels[ACPI_VIDEO_FIRST_LEVEL],
 934                      count - ACPI_VIDEO_FIRST_LEVEL,
 935                      sizeof(br->levels[ACPI_VIDEO_FIRST_LEVEL]),
 936                      acpi_video_cmp_level, NULL);
 937         } else if (max_level != br->levels[count - 1])
 938                 ACPI_ERROR((AE_INFO,
 939                             "Found unordered _BCL package"));
 940
 941         br->count = count;
 942         *dev_br = br;
 943         if (pmax_level)
 944                 *pmax_level = max_level;
 945
 946 out:
 947         kfree(obj);
 948         return result;
 949 out_free:
 950         kfree(br);
 951         goto out;
 952 }
 953 EXPORT_SYMBOL(acpi_video_get_levels);
 954
 955 /*
 956  *  Arg:
 957  *      device  : video output device (LCD, CRT, ..)
 958  *
 959  *  Return Value:
 960  *      Maximum brightness level
 961  *
 962  *  Allocate and initialize device->brightness.
 963  */
 964
 965 static int
 966 acpi_video_init_brightness(struct acpi_video_device *device)
 967 {
 968         int i, max_level = 0;
 969         unsigned long long level, level_old;
 970         struct acpi_video_device_brightness *br = NULL;
 971         int result;
 972
 973         result = acpi_video_get_levels(device->dev, &br, &max_level);
 974         if (result)
 975                 return result;
 976         device->brightness = br;
 977
 978         /* _BQC uses INDEX while _BCL uses VALUE in some laptops */
 979         br->curr = level = max_level;
 980
 981         if (!device->cap._BQC)
 982                 goto set_level;
 983
 984         result = acpi_video_device_lcd_get_level_current(device,
 985                                                          &level_old, true);
 986         if (result)
 987                 goto out_free_levels;
 988
 989         result = acpi_video_bqc_quirk(device, max_level, level_old);
 990         if (result)
 991                 goto out_free_levels;
 992         /*
 993          * cap._BQC may get cleared due to _BQC is found to be broken
 994          * in acpi_video_bqc_quirk, so check again here.
 995          */
 996         if (!device->cap._BQC)
 997                 goto set_level;
 998
 999         level = acpi_video_bqc_value_to_level(device, level_old);
1000         /*
1001          * On some buggy laptops, _BQC returns an uninitialized
1002          * value when invoked for the first time, i.e.
1003          * level_old is invalid (no matter whether it's a level
1004          * or an index). Set the backlight to max_level in this case.
1005          */
1006         for (i = ACPI_VIDEO_FIRST_LEVEL; i < br->count; i++)
1007                 if (level == br->levels[i])
1008                         break;
1009         if (i == br->count || !level)
1010                 level = max_level;
1011
1012 set_level:
1013         result = acpi_video_device_lcd_set_level(device, level);
1014         if (result)
1015                 goto out_free_levels;
1016
1017         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1018                           "found %d brightness levels\n",
1019                           br->count - ACPI_VIDEO_FIRST_LEVEL));
1020         return 0;
1021
1022 out_free_levels:
1023         kfree(br->levels);
1024         kfree(br);
1025         device->brightness = NULL;
1026         return result;
1027 }
1028
1029 /*
1030  *  Arg:
1031  *      device  : video output device (LCD, CRT, ..)
1032  *
1033  *  Return Value:
1034  *      None
1035  *
1036  *  Find out all required AML methods defined under the output
1037  *  device.
1038  */
1039
1040 static void acpi_video_device_find_cap(struct acpi_video_device *device)
1041 {
1042         if (acpi_has_method(device->dev->handle, "_ADR"))
1043                 device->cap._ADR = 1;
1044         if (acpi_has_method(device->dev->handle, "_BCL"))
1045                 device->cap._BCL = 1;
1046         if (acpi_has_method(device->dev->handle, "_BCM"))
1047                 device->cap._BCM = 1;
1048         if (acpi_has_method(device->dev->handle, "_BQC")) {
1049                 device->cap._BQC = 1;
1050         } else if (acpi_has_method(device->dev->handle, "_BCQ")) {
1051                 printk(KERN_WARNING FW_BUG "_BCQ is used instead of _BQC\n");
1052                 device->cap._BCQ = 1;
1053         }
1054
1055         if (acpi_has_method(device->dev->handle, "_DDC"))
1056                 device->cap._DDC = 1;
1057 }
1058
1059 /*
1060  *  Arg:
1061  *      device  : video output device (VGA)
1062  *
1063  *  Return Value:
1064  *      None
1065  *
1066  *  Find out all required AML methods defined under the video bus device.
1067  */
1068
1069 static void acpi_video_bus_find_cap(struct acpi_video_bus *video)
1070 {
1071         if (acpi_has_method(video->device->handle, "_DOS"))
1072                 video->cap._DOS = 1;
1073         if (acpi_has_method(video->device->handle, "_DOD"))
1074                 video->cap._DOD = 1;
1075         if (acpi_has_method(video->device->handle, "_ROM"))
1076                 video->cap._ROM = 1;
1077         if (acpi_has_method(video->device->handle, "_GPD"))
1078                 video->cap._GPD = 1;
1079         if (acpi_has_method(video->device->handle, "_SPD"))
1080                 video->cap._SPD = 1;
1081         if (acpi_has_method(video->device->handle, "_VPO"))
1082                 video->cap._VPO = 1;
1083 }
1084
1085 /*
1086  * Check whether the video bus device has required AML method to
1087  * support the desired features
1088  */
1089
1090 static int acpi_video_bus_check(struct acpi_video_bus *video)
1091 {
1092         acpi_status status = -ENOENT;
1093         struct pci_dev *dev;
1094
1095         if (!video)
1096                 return -EINVAL;
1097
1098         dev = acpi_get_pci_dev(video->device->handle);
1099         if (!dev)
1100                 return -ENODEV;
1101         pci_dev_put(dev);
1102
1103         /*
1104          * Since there is no HID, CID and so on for VGA driver, we have
1105          * to check well known required nodes.
1106          */
1107
1108         /* Does this device support video switching? */
1109         if (video->cap._DOS || video->cap._DOD) {
1110                 if (!video->cap._DOS) {
1111                         printk(KERN_WARNING FW_BUG
1112                                 "ACPI(%s) defines _DOD but not _DOS\n",
1113                                 acpi_device_bid(video->device));
1114                 }
1115                 video->flags.multihead = 1;
1116                 status = 0;
1117         }
1118
1119         /* Does this device support retrieving a video ROM? */
1120         if (video->cap._ROM) {
1121                 video->flags.rom = 1;
1122                 status = 0;
1123         }
1124
1125         /* Does this device support configuring which video device to POST? */
1126         if (video->cap._GPD && video->cap._SPD && video->cap._VPO) {
1127                 video->flags.post = 1;
1128                 status = 0;
1129         }
1130
1131         return status;
1132 }
1133
1134 /*
1135  * --------------------------------------------------------------------------
1136  *                               Driver Interface
1137  * --------------------------------------------------------------------------
1138  */
1139
1140 /* device interface */
1141 static struct acpi_video_device_attrib *
1142 acpi_video_get_device_attr(struct acpi_video_bus *video, unsigned long device_id)
1143 {
1144         struct acpi_video_enumerated_device *ids;
1145         int i;
1146
1147         for (i = 0; i < video->attached_count; i++) {
1148                 ids = &video->attached_array[i];
1149                 if ((ids->value.int_val & 0xffff) == device_id)
1150                         return &ids->value.attrib;
1151         }
1152
1153         return NULL;
1154 }
1155
1156 static int
1157 acpi_video_get_device_type(struct acpi_video_bus *video,
1158                            unsigned long device_id)
1159 {
1160         struct acpi_video_enumerated_device *ids;
1161         int i;
1162
1163         for (i = 0; i < video->attached_count; i++) {
1164                 ids = &video->attached_array[i];
1165                 if ((ids->value.int_val & 0xffff) == device_id)
1166                         return ids->value.int_val;
1167         }
1168
1169         return 0;
1170 }
1171
1172 static int
1173 acpi_video_bus_get_one_device(struct acpi_device *device,
1174                               struct acpi_video_bus *video)
1175 {
1176         unsigned long long device_id;
1177         int status, device_type;
1178         struct acpi_video_device *data;
1179         struct acpi_video_device_attrib *attribute;
1180
1181         status =
1182             acpi_evaluate_integer(device->handle, "_ADR", NULL, &device_id);
1183         /* Some device omits _ADR, we skip them instead of fail */
1184         if (ACPI_FAILURE(status))
1185                 return 0;
1186
1187         data = kzalloc(sizeof(struct acpi_video_device), GFP_KERNEL);
1188         if (!data)
1189                 return -ENOMEM;
1190
1191         strcpy(acpi_device_name(device), ACPI_VIDEO_DEVICE_NAME);
1192         strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
1193         device->driver_data = data;
1194
1195         data->device_id = device_id;
1196         data->video = video;
1197         data->dev = device;
1198         INIT_DELAYED_WORK(&data->switch_brightness_work,
1199                           acpi_video_switch_brightness);
1200
1201         attribute = acpi_video_get_device_attr(video, device_id);
1202
1203         if (attribute && (attribute->device_id_scheme || device_id_scheme)) {
1204                 switch (attribute->display_type) {
1205                 case ACPI_VIDEO_DISPLAY_CRT:
1206                         data->flags.crt = 1;
1207                         break;
1208                 case ACPI_VIDEO_DISPLAY_TV:
1209                         data->flags.tvout = 1;
1210                         break;
1211                 case ACPI_VIDEO_DISPLAY_DVI:
1212                         data->flags.dvi = 1;
1213                         break;
1214                 case ACPI_VIDEO_DISPLAY_LCD:
1215                         data->flags.lcd = 1;
1216                         break;
1217                 default:
1218                         data->flags.unknown = 1;
1219                         break;
1220                 }
1221                 if (attribute->bios_can_detect)
1222                         data->flags.bios = 1;
1223         } else {
1224                 /* Check for legacy IDs */
1225                 device_type = acpi_video_get_device_type(video, device_id);
1226                 /* Ignore bits 16 and 18-20 */
1227                 switch (device_type & 0xffe2ffff) {
1228                 case ACPI_VIDEO_DISPLAY_LEGACY_MONITOR:
1229                         data->flags.crt = 1;
1230                         break;
1231                 case ACPI_VIDEO_DISPLAY_LEGACY_PANEL:
1232                         data->flags.lcd = 1;
1233                         break;
1234                 case ACPI_VIDEO_DISPLAY_LEGACY_TV:
1235                         data->flags.tvout = 1;
1236                         break;
1237                 default:
1238                         data->flags.unknown = 1;
1239                 }
1240         }
1241
1242         acpi_video_device_bind(video, data);
1243         acpi_video_device_find_cap(data);
1244
1245         mutex_lock(&video->device_list_lock);
1246         list_add_tail(&data->entry, &video->video_device_list);
1247         mutex_unlock(&video->device_list_lock);
1248
1249         return status;
1250 }
1251
1252 /*
1253  *  Arg:
1254  *      video   : video bus device
1255  *
1256  *  Return:
1257  *      none
1258  *
1259  *  Enumerate the video device list of the video bus,
1260  *  bind the ids with the corresponding video devices
1261  *  under the video bus.
1262  */
1263
1264 static void acpi_video_device_rebind(struct acpi_video_bus *video)
1265 {
1266         struct acpi_video_device *dev;
1267
1268         mutex_lock(&video->device_list_lock);
1269
1270         list_for_each_entry(dev, &video->video_device_list, entry)
1271                 acpi_video_device_bind(video, dev);
1272
1273         mutex_unlock(&video->device_list_lock);
1274 }
1275
1276 /*
1277  *  Arg:
1278  *      video   : video bus device
1279  *      device  : video output device under the video
1280  *              bus
1281  *
1282  *  Return:
1283  *      none
1284  *
1285  *  Bind the ids with the corresponding video devices
1286  *  under the video bus.
1287  */
1288
1289 static void
1290 acpi_video_device_bind(struct acpi_video_bus *video,
1291                        struct acpi_video_device *device)
1292 {
1293         struct acpi_video_enumerated_device *ids;
1294         int i;
1295
1296         for (i = 0; i < video->attached_count; i++) {
1297                 ids = &video->attached_array[i];
1298                 if (device->device_id == (ids->value.int_val & 0xffff)) {
1299                         ids->bind_info = device;
1300                         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "device_bind %d\n", i));
1301                 }
1302         }
1303 }
1304
1305 static bool acpi_video_device_in_dod(struct acpi_video_device *device)
1306 {
1307         struct acpi_video_bus *video = device->video;
1308         int i;
1309
1310         /*
1311          * If we have a broken _DOD or we have more than 8 output devices
1312          * under the graphics controller node that we can't proper deal with
1313          * in the operation region code currently, no need to test.
1314          */
1315         if (!video->attached_count || video->child_count > 8)
1316                 return true;
1317
1318         for (i = 0; i < video->attached_count; i++) {
1319                 if ((video->attached_array[i].value.int_val & 0xfff) ==
1320                     (device->device_id & 0xfff))
1321                         return true;
1322         }
1323
1324         return false;
1325 }
1326
1327 /*
1328  *  Arg:
1329  *      video   : video bus device
1330  *
1331  *  Return:
1332  *      < 0     : error
1333  *
1334  *  Call _DOD to enumerate all devices attached to display adapter
1335  *
1336  */
1337
1338 static int acpi_video_device_enumerate(struct acpi_video_bus *video)
1339 {
1340         int status;
1341         int count;
1342         int i;
1343         struct acpi_video_enumerated_device *active_list;
1344         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1345         union acpi_object *dod = NULL;
1346         union acpi_object *obj;
1347
1348         if (!video->cap._DOD)
1349                 return AE_NOT_EXIST;
1350
1351         status = acpi_evaluate_object(video->device->handle, "_DOD", NULL, &buffer);
1352         if (!ACPI_SUCCESS(status)) {
1353                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _DOD"));
1354                 return status;
1355         }
1356
1357         dod = buffer.pointer;
1358         if (!dod || (dod->type != ACPI_TYPE_PACKAGE)) {
1359                 ACPI_EXCEPTION((AE_INFO, status, "Invalid _DOD data"));
1360                 status = -EFAULT;
1361                 goto out;
1362         }
1363
1364         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d video heads in _DOD\n",
1365                           dod->package.count));
1366
1367         active_list = kcalloc(1 + dod->package.count,
1368                               sizeof(struct acpi_video_enumerated_device),
1369                               GFP_KERNEL);
1370         if (!active_list) {
1371                 status = -ENOMEM;
1372                 goto out;
1373         }
1374
1375         count = 0;
1376         for (i = 0; i < dod->package.count; i++) {
1377                 obj = &dod->package.elements[i];
1378
1379                 if (obj->type != ACPI_TYPE_INTEGER) {
1380                         printk(KERN_ERR PREFIX
1381                                 "Invalid _DOD data in element %d\n", i);
1382                         continue;
1383                 }
1384
1385                 active_list[count].value.int_val = obj->integer.value;
1386                 active_list[count].bind_info = NULL;
1387                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "dod element[%d] = %d\n", i,
1388                                   (int)obj->integer.value));
1389                 count++;
1390         }
1391
1392         kfree(video->attached_array);
1393
1394         video->attached_array = active_list;
1395         video->attached_count = count;
1396
1397 out:
1398         kfree(buffer.pointer);
1399         return status;
1400 }
1401
1402 static int
1403 acpi_video_get_next_level(struct acpi_video_device *device,
1404                           u32 level_current, u32 event)
1405 {
1406         int min, max, min_above, max_below, i, l, delta = 255;
1407         max = max_below = 0;
1408         min = min_above = 255;
1409         /* Find closest level to level_current */
1410         for (i = ACPI_VIDEO_FIRST_LEVEL; i < device->brightness->count; i++) {
1411                 l = device->brightness->levels[i];
1412                 if (abs(l - level_current) < abs(delta)) {
1413                         delta = l - level_current;
1414                         if (!delta)
1415                                 break;
1416                 }
1417         }
1418         /* Ajust level_current to closest available level */
1419         level_current += delta;
1420         for (i = ACPI_VIDEO_FIRST_LEVEL; i < device->brightness->count; i++) {
1421                 l = device->brightness->levels[i];
1422                 if (l < min)
1423                         min = l;
1424                 if (l > max)
1425                         max = l;
1426                 if (l < min_above && l > level_current)
1427                         min_above = l;
1428                 if (l > max_below && l < level_current)
1429                         max_below = l;
1430         }
1431
1432         switch (event) {
1433         case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:
1434                 return (level_current < max) ? min_above : min;
1435         case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:
1436                 return (level_current < max) ? min_above : max;
1437         case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:
1438                 return (level_current > min) ? max_below : min;
1439         case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS:
1440         case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:
1441                 return 0;
1442         default:
1443                 return level_current;
1444         }
1445 }
1446
1447 static void
1448 acpi_video_switch_brightness(struct work_struct *work)
1449 {
1450         struct acpi_video_device *device = container_of(to_delayed_work(work),
1451                              struct acpi_video_device, switch_brightness_work);
1452         unsigned long long level_current, level_next;
1453         int event = device->switch_brightness_event;
1454         int result = -EINVAL;
1455
1456         /* no warning message if acpi_backlight=vendor or a quirk is used */
1457         if (!device->backlight)
1458                 return;
1459
1460         if (!device->brightness)
1461                 goto out;
1462
1463         result = acpi_video_device_lcd_get_level_current(device,
1464                                                          &level_current,
1465                                                          false);
1466         if (result)
1467                 goto out;
1468
1469         level_next = acpi_video_get_next_level(device, level_current, event);
1470
1471         result = acpi_video_device_lcd_set_level(device, level_next);
1472
1473         if (!result)
1474                 backlight_force_update(device->backlight,
1475                                        BACKLIGHT_UPDATE_HOTKEY);
1476
1477 out:
1478         if (result)
1479                 printk(KERN_ERR PREFIX "Failed to switch the brightness\n");
1480 }
1481
1482 int acpi_video_get_edid(struct acpi_device *device, int type, int device_id,
1483                         void **edid)
1484 {
1485         struct acpi_video_bus *video;
1486         struct acpi_video_device *video_device;
1487         union acpi_object *buffer = NULL;
1488         acpi_status status;
1489         int i, length;
1490
1491         if (!device || !acpi_driver_data(device))
1492                 return -EINVAL;
1493
1494         video = acpi_driver_data(device);
1495
1496         for (i = 0; i < video->attached_count; i++) {
1497                 video_device = video->attached_array[i].bind_info;
1498                 length = 256;
1499
1500                 if (!video_device)
1501                         continue;
1502
1503                 if (!video_device->cap._DDC)
1504                         continue;
1505
1506                 if (type) {
1507                         switch (type) {
1508                         case ACPI_VIDEO_DISPLAY_CRT:
1509                                 if (!video_device->flags.crt)
1510                                         continue;
1511                                 break;
1512                         case ACPI_VIDEO_DISPLAY_TV:
1513                                 if (!video_device->flags.tvout)
1514                                         continue;
1515                                 break;
1516                         case ACPI_VIDEO_DISPLAY_DVI:
1517                                 if (!video_device->flags.dvi)
1518                                         continue;
1519                                 break;
1520                         case ACPI_VIDEO_DISPLAY_LCD:
1521                                 if (!video_device->flags.lcd)
1522                                         continue;
1523                                 break;
1524                         }
1525                 } else if (video_device->device_id != device_id) {
1526                         continue;
1527                 }
1528
1529                 status = acpi_video_device_EDID(video_device, &buffer, length);
1530
1531                 if (ACPI_FAILURE(status) || !buffer ||
1532                     buffer->type != ACPI_TYPE_BUFFER) {
1533                         length = 128;
1534                         status = acpi_video_device_EDID(video_device, &buffer,
1535                                                         length);
1536                         if (ACPI_FAILURE(status) || !buffer ||
1537                             buffer->type != ACPI_TYPE_BUFFER) {
1538                                 continue;
1539                         }
1540                 }
1541
1542                 *edid = buffer->buffer.pointer;
1543                 return length;
1544         }
1545
1546         return -ENODEV;
1547 }
1548 EXPORT_SYMBOL(acpi_video_get_edid);
1549
1550 static int
1551 acpi_video_bus_get_devices(struct acpi_video_bus *video,
1552                            struct acpi_device *device)
1553 {
1554         int status = 0;
1555         struct acpi_device *dev;
1556
1557         /*
1558          * There are systems where video module known to work fine regardless
1559          * of broken _DOD and ignoring returned value here doesn't cause
1560          * any issues later.
1561          */
1562         acpi_video_device_enumerate(video);
1563
1564         list_for_each_entry(dev, &device->children, node) {
1565
1566                 status = acpi_video_bus_get_one_device(dev, video);
1567                 if (status) {
1568                         dev_err(&dev->dev, "Can't attach device\n");
1569                         break;
1570                 }
1571                 video->child_count++;
1572         }
1573         return status;
1574 }
1575
1576 /* acpi_video interface */
1577
1578 /*
1579  * Win8 requires setting bit2 of _DOS to let firmware know it shouldn't
1580  * preform any automatic brightness change on receiving a notification.
1581  */
1582 static int acpi_video_bus_start_devices(struct acpi_video_bus *video)
1583 {
1584         return acpi_video_bus_DOS(video, 0,
1585                                   acpi_osi_is_win8() ? 1 : 0);
1586 }
1587
1588 static int acpi_video_bus_stop_devices(struct acpi_video_bus *video)
1589 {
1590         return acpi_video_bus_DOS(video, 0,
1591                                   acpi_osi_is_win8() ? 0 : 1);
1592 }
1593
1594 static void acpi_video_bus_notify(struct acpi_device *device, u32 event)
1595 {
1596         struct acpi_video_bus *video = acpi_driver_data(device);
1597         struct input_dev *input;
1598         int keycode = 0;
1599
1600         if (!video || !video->input)
1601                 return;
1602
1603         input = video->input;
1604
1605         switch (event) {
1606         case ACPI_VIDEO_NOTIFY_SWITCH:  /* User requested a switch,
1607                                          * most likely via hotkey. */
1608                 keycode = KEY_SWITCHVIDEOMODE;
1609                 break;
1610
1611         case ACPI_VIDEO_NOTIFY_PROBE:   /* User plugged in or removed a video
1612                                          * connector. */
1613                 acpi_video_device_enumerate(video);
1614                 acpi_video_device_rebind(video);
1615                 keycode = KEY_SWITCHVIDEOMODE;
1616                 break;
1617
1618         case ACPI_VIDEO_NOTIFY_CYCLE:   /* Cycle Display output hotkey pressed. */
1619                 keycode = KEY_SWITCHVIDEOMODE;
1620                 break;
1621         case ACPI_VIDEO_NOTIFY_NEXT_OUTPUT:     /* Next Display output hotkey pressed. */
1622                 keycode = KEY_VIDEO_NEXT;
1623                 break;
1624         case ACPI_VIDEO_NOTIFY_PREV_OUTPUT:     /* previous Display output hotkey pressed. */
1625                 keycode = KEY_VIDEO_PREV;
1626                 break;
1627
1628         default:
1629                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1630                                   "Unsupported event [0x%x]\n", event));
1631                 break;
1632         }
1633
1634         if (acpi_notifier_call_chain(device, event, 0))
1635                 /* Something vetoed the keypress. */
1636                 keycode = 0;
1637
1638         if (keycode && (report_key_events & REPORT_OUTPUT_KEY_EVENTS)) {
1639                 input_report_key(input, keycode, 1);
1640                 input_sync(input);
1641                 input_report_key(input, keycode, 0);
1642                 input_sync(input);
1643         }
1644
1645         return;
1646 }
1647
1648 static void brightness_switch_event(struct acpi_video_device *video_device,
1649                                     u32 event)
1650 {
1651         if (!brightness_switch_enabled)
1652                 return;
1653
1654         video_device->switch_brightness_event = event;
1655         schedule_delayed_work(&video_device->switch_brightness_work, HZ / 10);
1656 }
1657
1658 static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data)
1659 {
1660         struct acpi_video_device *video_device = data;
1661         struct acpi_device *device = NULL;
1662         struct acpi_video_bus *bus;
1663         struct input_dev *input;
1664         int keycode = 0;
1665
1666         if (!video_device)
1667                 return;
1668
1669         device = video_device->dev;
1670         bus = video_device->video;
1671         input = bus->input;
1672
1673         if (hw_changes_brightness > 0) {
1674                 if (video_device->backlight)
1675                         backlight_force_update(video_device->backlight,
1676                                                BACKLIGHT_UPDATE_HOTKEY);
1677                 acpi_notifier_call_chain(device, event, 0);
1678                 return;
1679         }
1680
1681         switch (event) {
1682         case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:        /* Cycle brightness */
1683                 brightness_switch_event(video_device, event);
1684                 keycode = KEY_BRIGHTNESS_CYCLE;
1685                 break;
1686         case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:  /* Increase brightness */
1687                 brightness_switch_event(video_device, event);
1688                 keycode = KEY_BRIGHTNESSUP;
1689                 break;
1690         case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:  /* Decrease brightness */
1691                 brightness_switch_event(video_device, event);
1692                 keycode = KEY_BRIGHTNESSDOWN;
1693                 break;
1694         case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS: /* zero brightness */
1695                 brightness_switch_event(video_device, event);
1696                 keycode = KEY_BRIGHTNESS_ZERO;
1697                 break;
1698         case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:     /* display device off */
1699                 brightness_switch_event(video_device, event);
1700                 keycode = KEY_DISPLAY_OFF;
1701                 break;
1702         default:
1703                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1704                                   "Unsupported event [0x%x]\n", event));
1705                 break;
1706         }
1707
1708         acpi_notifier_call_chain(device, event, 0);
1709
1710         if (keycode && (report_key_events & REPORT_BRIGHTNESS_KEY_EVENTS)) {
1711                 input_report_key(input, keycode, 1);
1712                 input_sync(input);
1713                 input_report_key(input, keycode, 0);
1714                 input_sync(input);
1715         }
1716
1717         return;
1718 }
1719
1720 static int acpi_video_resume(struct notifier_block *nb,
1721                                 unsigned long val, void *ign)
1722 {
1723         struct acpi_video_bus *video;
1724         struct acpi_video_device *video_device;
1725         int i;
1726
1727         switch (val) {
1728         case PM_HIBERNATION_PREPARE:
1729         case PM_SUSPEND_PREPARE:
1730         case PM_RESTORE_PREPARE:
1731                 return NOTIFY_DONE;
1732         }
1733
1734         video = container_of(nb, struct acpi_video_bus, pm_nb);
1735
1736         dev_info(&video->device->dev, "Restoring backlight state\n");
1737
1738         for (i = 0; i < video->attached_count; i++) {
1739                 video_device = video->attached_array[i].bind_info;
1740                 if (video_device && video_device->brightness)
1741                         acpi_video_device_lcd_set_level(video_device,
1742                                         video_device->brightness->curr);
1743         }
1744
1745         return NOTIFY_OK;
1746 }
1747
1748 static acpi_status
1749 acpi_video_bus_match(acpi_handle handle, u32 level, void *context,
1750                         void **return_value)
1751 {
1752         struct acpi_device *device = context;
1753         struct acpi_device *sibling;
1754         int result;
1755
1756         if (handle == device->handle)
1757                 return AE_CTRL_TERMINATE;
1758
1759         result = acpi_bus_get_device(handle, &sibling);
1760         if (result)
1761                 return AE_OK;
1762
1763         if (!strcmp(acpi_device_name(sibling), ACPI_VIDEO_BUS_NAME))
1764                         return AE_ALREADY_EXISTS;
1765
1766         return AE_OK;
1767 }
1768
1769 static void acpi_video_dev_register_backlight(struct acpi_video_device *device)
1770 {
1771         struct backlight_properties props;
1772         struct pci_dev *pdev;
1773         acpi_handle acpi_parent;
1774         struct device *parent = NULL;
1775         int result;
1776         static int count;
1777         char *name;
1778
1779         result = acpi_video_init_brightness(device);
1780         if (result)
1781                 return;
1782
1783         if (disable_backlight_sysfs_if > 0)
1784                 return;
1785
1786         name = kasprintf(GFP_KERNEL, "acpi_video%d", count);
1787         if (!name)
1788                 return;
1789         count++;
1790
1791         acpi_get_parent(device->dev->handle, &acpi_parent);
1792
1793         pdev = acpi_get_pci_dev(acpi_parent);
1794         if (pdev) {
1795                 parent = &pdev->dev;
1796                 pci_dev_put(pdev);
1797         }
1798
1799         memset(&props, 0, sizeof(struct backlight_properties));
1800         props.type = BACKLIGHT_FIRMWARE;
1801         props.max_brightness =
1802                 device->brightness->count - ACPI_VIDEO_FIRST_LEVEL - 1;
1803         device->backlight = backlight_device_register(name,
1804                                                       parent,
1805                                                       device,
1806                                                       &acpi_backlight_ops,
1807                                                       &props);
1808         kfree(name);
1809         if (IS_ERR(device->backlight)) {
1810                 device->backlight = NULL;
1811                 return;
1812         }
1813
1814         /*
1815          * Save current brightness level in case we have to restore it
1816          * before acpi_video_device_lcd_set_level() is called next time.
1817          */
1818         device->backlight->props.brightness =
1819                         acpi_video_get_brightness(device->backlight);
1820
1821         device->cooling_dev = thermal_cooling_device_register("LCD",
1822                                 device->dev, &video_cooling_ops);
1823         if (IS_ERR(device->cooling_dev)) {
1824                 /*
1825                  * Set cooling_dev to NULL so we don't crash trying to free it.
1826                  * Also, why the hell we are returning early and not attempt to
1827                  * register video output if cooling device registration failed?
1828                  * -- dtor
1829                  */
1830                 device->cooling_dev = NULL;
1831                 return;
1832         }
1833
1834         dev_info(&device->dev->dev, "registered as cooling_device%d\n",
1835                  device->cooling_dev->id);
1836         result = sysfs_create_link(&device->dev->dev.kobj,
1837                         &device->cooling_dev->device.kobj,
1838                         "thermal_cooling");
1839         if (result)
1840                 printk(KERN_ERR PREFIX "Create sysfs link\n");
1841         result = sysfs_create_link(&device->cooling_dev->device.kobj,
1842                         &device->dev->dev.kobj, "device");
1843         if (result)
1844                 printk(KERN_ERR PREFIX "Create sysfs link\n");
1845 }
1846
1847 static void acpi_video_run_bcl_for_osi(struct acpi_video_bus *video)
1848 {
1849         struct acpi_video_device *dev;
1850         union acpi_object *levels;
1851
1852         mutex_lock(&video->device_list_lock);
1853         list_for_each_entry(dev, &video->video_device_list, entry) {
1854                 if (!acpi_video_device_lcd_query_levels(dev->dev->handle, &levels))
1855                         kfree(levels);
1856         }
1857         mutex_unlock(&video->device_list_lock);
1858 }
1859
1860 static bool acpi_video_should_register_backlight(struct acpi_video_device *dev)
1861 {
1862         /*
1863          * Do not create backlight device for video output
1864          * device that is not in the enumerated list.
1865          */
1866         if (!acpi_video_device_in_dod(dev)) {
1867                 dev_dbg(&dev->dev->dev, "not in _DOD list, ignore\n");
1868                 return false;
1869         }
1870
1871         if (only_lcd)
1872                 return dev->flags.lcd;
1873         return true;
1874 }
1875
1876 static int acpi_video_bus_register_backlight(struct acpi_video_bus *video)
1877 {
1878         struct acpi_video_device *dev;
1879
1880         if (video->backlight_registered)
1881                 return 0;
1882
1883         acpi_video_run_bcl_for_osi(video);
1884
1885         if (acpi_video_get_backlight_type() != acpi_backlight_video)
1886                 return 0;
1887
1888         mutex_lock(&video->device_list_lock);
1889         list_for_each_entry(dev, &video->video_device_list, entry) {
1890                 if (acpi_video_should_register_backlight(dev))
1891                         acpi_video_dev_register_backlight(dev);
1892         }
1893         mutex_unlock(&video->device_list_lock);
1894
1895         video->backlight_registered = true;
1896
1897         video->pm_nb.notifier_call = acpi_video_resume;
1898         video->pm_nb.priority = 0;
1899         return register_pm_notifier(&video->pm_nb);
1900 }
1901
1902 static void acpi_video_dev_unregister_backlight(struct acpi_video_device *device)
1903 {
1904         if (device->backlight) {
1905                 backlight_device_unregister(device->backlight);
1906                 device->backlight = NULL;
1907         }
1908         if (device->brightness) {
1909                 kfree(device->brightness->levels);
1910                 kfree(device->brightness);
1911                 device->brightness = NULL;
1912         }
1913         if (device->cooling_dev) {
1914                 sysfs_remove_link(&device->dev->dev.kobj, "thermal_cooling");
1915                 sysfs_remove_link(&device->cooling_dev->device.kobj, "device");
1916                 thermal_cooling_device_unregister(device->cooling_dev);
1917                 device->cooling_dev = NULL;
1918         }
1919 }
1920
1921 static int acpi_video_bus_unregister_backlight(struct acpi_video_bus *video)
1922 {
1923         struct acpi_video_device *dev;
1924         int error;
1925
1926         if (!video->backlight_registered)
1927                 return 0;
1928
1929         error = unregister_pm_notifier(&video->pm_nb);
1930
1931         mutex_lock(&video->device_list_lock);
1932         list_for_each_entry(dev, &video->video_device_list, entry)
1933                 acpi_video_dev_unregister_backlight(dev);
1934         mutex_unlock(&video->device_list_lock);
1935
1936         video->backlight_registered = false;
1937
1938         return error;
1939 }
1940
1941 static void acpi_video_dev_add_notify_handler(struct acpi_video_device *device)
1942 {
1943         acpi_status status;
1944         struct acpi_device *adev = device->dev;
1945
1946         status = acpi_install_notify_handler(adev->handle, ACPI_DEVICE_NOTIFY,
1947                                              acpi_video_device_notify, device);
1948         if (ACPI_FAILURE(status))
1949                 dev_err(&adev->dev, "Error installing notify handler\n");
1950         else
1951                 device->flags.notify = 1;
1952 }
1953
1954 static int acpi_video_bus_add_notify_handler(struct acpi_video_bus *video)
1955 {
1956         struct input_dev *input;
1957         struct acpi_video_device *dev;
1958         int error;
1959
1960         video->input = input = input_allocate_device();
1961         if (!input) {
1962                 error = -ENOMEM;
1963                 goto out;
1964         }
1965
1966         error = acpi_video_bus_start_devices(video);
1967         if (error)
1968                 goto err_free_input;
1969
1970         snprintf(video->phys, sizeof(video->phys),
1971                         "%s/video/input0", acpi_device_hid(video->device));
1972
1973         input->name = acpi_device_name(video->device);
1974         input->phys = video->phys;
1975         input->id.bustype = BUS_HOST;
1976         input->id.product = 0x06;
1977         input->dev.parent = &video->device->dev;
1978         input->evbit[0] = BIT(EV_KEY);
1979         set_bit(KEY_SWITCHVIDEOMODE, input->keybit);
1980         set_bit(KEY_VIDEO_NEXT, input->keybit);
1981         set_bit(KEY_VIDEO_PREV, input->keybit);
1982         set_bit(KEY_BRIGHTNESS_CYCLE, input->keybit);
1983         set_bit(KEY_BRIGHTNESSUP, input->keybit);
1984         set_bit(KEY_BRIGHTNESSDOWN, input->keybit);
1985         set_bit(KEY_BRIGHTNESS_ZERO, input->keybit);
1986         set_bit(KEY_DISPLAY_OFF, input->keybit);
1987
1988         error = input_register_device(input);
1989         if (error)
1990                 goto err_stop_dev;
1991
1992         mutex_lock(&video->device_list_lock);
1993         list_for_each_entry(dev, &video->video_device_list, entry)
1994                 acpi_video_dev_add_notify_handler(dev);
1995         mutex_unlock(&video->device_list_lock);
1996
1997         return 0;
1998
1999 err_stop_dev:
2000         acpi_video_bus_stop_devices(video);
2001 err_free_input:
2002         input_free_device(input);
2003         video->input = NULL;
2004 out:
2005         return error;
2006 }
2007
2008 static void acpi_video_dev_remove_notify_handler(struct acpi_video_device *dev)
2009 {
2010         if (dev->flags.notify) {
2011                 acpi_remove_notify_handler(dev->dev->handle, ACPI_DEVICE_NOTIFY,
2012                                            acpi_video_device_notify);
2013                 dev->flags.notify = 0;
2014         }
2015 }
2016
2017 static void acpi_video_bus_remove_notify_handler(struct acpi_video_bus *video)
2018 {
2019         struct acpi_video_device *dev;
2020
2021         mutex_lock(&video->device_list_lock);
2022         list_for_each_entry(dev, &video->video_device_list, entry)
2023                 acpi_video_dev_remove_notify_handler(dev);
2024         mutex_unlock(&video->device_list_lock);
2025
2026         acpi_video_bus_stop_devices(video);
2027         input_unregister_device(video->input);
2028         video->input = NULL;
2029 }
2030
2031 static int acpi_video_bus_put_devices(struct acpi_video_bus *video)
2032 {
2033         struct acpi_video_device *dev, *next;
2034
2035         mutex_lock(&video->device_list_lock);
2036         list_for_each_entry_safe(dev, next, &video->video_device_list, entry) {
2037                 list_del(&dev->entry);
2038                 kfree(dev);
2039         }
2040         mutex_unlock(&video->device_list_lock);
2041
2042         return 0;
2043 }
2044
2045 static int instance;
2046
2047 static int acpi_video_bus_add(struct acpi_device *device)
2048 {
2049         struct acpi_video_bus *video;
2050         int error;
2051         acpi_status status;
2052
2053         status = acpi_walk_namespace(ACPI_TYPE_DEVICE,
2054                                 device->parent->handle, 1,
2055                                 acpi_video_bus_match, NULL,
2056                                 device, NULL);
2057         if (status == AE_ALREADY_EXISTS) {
2058                 printk(KERN_WARNING FW_BUG
2059                         "Duplicate ACPI video bus devices for the"
2060                         " same VGA controller, please try module "
2061                         "parameter \"video.allow_duplicates=1\""
2062                         "if the current driver doesn't work.\n");
2063                 if (!allow_duplicates)
2064                         return -ENODEV;
2065         }
2066
2067         video = kzalloc(sizeof(struct acpi_video_bus), GFP_KERNEL);
2068         if (!video)
2069                 return -ENOMEM;
2070
2071         /* a hack to fix the duplicate name "VID" problem on T61 */
2072         if (!strcmp(device->pnp.bus_id, "VID")) {
2073                 if (instance)
2074                         device->pnp.bus_id[3] = '0' + instance;
2075                 instance++;
2076         }
2077         /* a hack to fix the duplicate name "VGA" problem on Pa 3553 */
2078         if (!strcmp(device->pnp.bus_id, "VGA")) {
2079                 if (instance)
2080                         device->pnp.bus_id[3] = '0' + instance;
2081                 instance++;
2082         }
2083
2084         video->device = device;
2085         strcpy(acpi_device_name(device), ACPI_VIDEO_BUS_NAME);
2086         strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
2087         device->driver_data = video;
2088
2089         acpi_video_bus_find_cap(video);
2090         error = acpi_video_bus_check(video);
2091         if (error)
2092                 goto err_free_video;
2093
2094         mutex_init(&video->device_list_lock);
2095         INIT_LIST_HEAD(&video->video_device_list);
2096
2097         error = acpi_video_bus_get_devices(video, device);
2098         if (error)
2099                 goto err_put_video;
2100
2101         printk(KERN_INFO PREFIX "%s [%s] (multi-head: %s  rom: %s  post: %s)\n",
2102                ACPI_VIDEO_DEVICE_NAME, acpi_device_bid(device),
2103                video->flags.multihead ? "yes" : "no",
2104                video->flags.rom ? "yes" : "no",
2105                video->flags.post ? "yes" : "no");
2106         mutex_lock(&video_list_lock);
2107         list_add_tail(&video->entry, &video_bus_head);
2108         mutex_unlock(&video_list_lock);
2109
2110         acpi_video_bus_register_backlight(video);
2111         acpi_video_bus_add_notify_handler(video);
2112
2113         return 0;
2114
2115 err_put_video:
2116         acpi_video_bus_put_devices(video);
2117         kfree(video->attached_array);
2118 err_free_video:
2119         kfree(video);
2120         device->driver_data = NULL;
2121
2122         return error;
2123 }
2124
2125 static int acpi_video_bus_remove(struct acpi_device *device)
2126 {
2127         struct acpi_video_bus *video = NULL;
2128
2129
2130         if (!device || !acpi_driver_data(device))
2131                 return -EINVAL;
2132
2133         video = acpi_driver_data(device);
2134
2135         acpi_video_bus_remove_notify_handler(video);
2136         acpi_video_bus_unregister_backlight(video);
2137         acpi_video_bus_put_devices(video);
2138
2139         mutex_lock(&video_list_lock);
2140         list_del(&video->entry);
2141         mutex_unlock(&video_list_lock);
2142
2143         kfree(video->attached_array);
2144         kfree(video);
2145
2146         return 0;
2147 }
2148
2149 static int __init is_i740(struct pci_dev *dev)
2150 {
2151         if (dev->device == 0x00D1)
2152                 return 1;
2153         if (dev->device == 0x7000)
2154                 return 1;
2155         return 0;
2156 }
2157
2158 static int __init intel_opregion_present(void)
2159 {
2160         int opregion = 0;
2161         struct pci_dev *dev = NULL;
2162         u32 address;
2163
2164         for_each_pci_dev(dev) {
2165                 if ((dev->class >> 8) != PCI_CLASS_DISPLAY_VGA)
2166                         continue;
2167                 if (dev->vendor != PCI_VENDOR_ID_INTEL)
2168                         continue;
2169                 /* We don't want to poke around undefined i740 registers */
2170                 if (is_i740(dev))
2171                         continue;
2172                 pci_read_config_dword(dev, 0xfc, &address);
2173                 if (!address)
2174                         continue;
2175                 opregion = 1;
2176         }
2177         return opregion;
2178 }
2179
2180 /* Check if the chassis-type indicates there is no builtin LCD panel */
2181 static bool dmi_is_desktop(void)
2182 {
2183         const char *chassis_type;
2184         unsigned long type;
2185
2186         chassis_type = dmi_get_system_info(DMI_CHASSIS_TYPE);
2187         if (!chassis_type)
2188                 return false;
2189
2190         if (kstrtoul(chassis_type, 10, &type) != 0)
2191                 return false;
2192
2193         switch (type) {
2194         case 0x03: /* Desktop */
2195         case 0x04: /* Low Profile Desktop */
2196         case 0x05: /* Pizza Box */
2197         case 0x06: /* Mini Tower */
2198         case 0x07: /* Tower */
2199         case 0x10: /* Lunch Box */
2200         case 0x11: /* Main Server Chassis */
2201                 return true;
2202         }
2203
2204         return false;
2205 }
2206
2207 int acpi_video_register(void)
2208 {
2209         int ret = 0;
2210
2211         mutex_lock(&register_count_mutex);
2212         if (register_count) {
2213                 /*
2214                  * if the function of acpi_video_register is already called,
2215                  * don't register the acpi_video_bus again and return no error.
2216                  */
2217                 goto leave;
2218         }
2219
2220         /*
2221          * We're seeing a lot of bogus backlight interfaces on newer machines
2222          * without a LCD such as desktops, servers and HDMI sticks. Checking
2223          * the lcd flag fixes this, so enable this on any machines which are
2224          * win8 ready (where we also prefer the native backlight driver, so
2225          * normally the acpi_video code should not register there anyways).
2226          */
2227         if (only_lcd == -1) {
2228                 if (dmi_is_desktop() && acpi_osi_is_win8())
2229                         only_lcd = true;
2230                 else
2231                         only_lcd = false;
2232         }
2233
2234         dmi_check_system(video_dmi_table);
2235
2236         ret = acpi_bus_register_driver(&acpi_video_bus);
2237         if (ret)
2238                 goto leave;
2239
2240         /*
2241          * When the acpi_video_bus is loaded successfully, increase
2242          * the counter reference.
2243          */
2244         register_count = 1;
2245
2246 leave:
2247         mutex_unlock(&register_count_mutex);
2248         return ret;
2249 }
2250 EXPORT_SYMBOL(acpi_video_register);
2251
2252 void acpi_video_unregister(void)
2253 {
2254         mutex_lock(&register_count_mutex);
2255         if (register_count) {
2256                 acpi_bus_unregister_driver(&acpi_video_bus);
2257                 register_count = 0;
2258         }
2259         mutex_unlock(&register_count_mutex);
2260 }
2261 EXPORT_SYMBOL(acpi_video_unregister);
2262
2263 void acpi_video_unregister_backlight(void)
2264 {
2265         struct acpi_video_bus *video;
2266
2267         mutex_lock(&register_count_mutex);
2268         if (register_count) {
2269                 mutex_lock(&video_list_lock);
2270                 list_for_each_entry(video, &video_bus_head, entry)
2271                         acpi_video_bus_unregister_backlight(video);
2272                 mutex_unlock(&video_list_lock);
2273         }
2274         mutex_unlock(&register_count_mutex);
2275 }
2276
2277 bool acpi_video_handles_brightness_key_presses(void)
2278 {
2279         bool have_video_busses;
2280
2281         mutex_lock(&video_list_lock);
2282         have_video_busses = !list_empty(&video_bus_head);
2283         mutex_unlock(&video_list_lock);
2284
2285         return have_video_busses &&
2286                (report_key_events & REPORT_BRIGHTNESS_KEY_EVENTS);
2287 }
2288 EXPORT_SYMBOL(acpi_video_handles_brightness_key_presses);
2289
2290 /*
2291  * This is kind of nasty. Hardware using Intel chipsets may require
2292  * the video opregion code to be run first in order to initialise
2293  * state before any ACPI video calls are made. To handle this we defer
2294  * registration of the video class until the opregion code has run.
2295  */
2296
2297 static int __init acpi_video_init(void)
2298 {
2299         /*
2300          * Let the module load even if ACPI is disabled (e.g. due to
2301          * a broken BIOS) so that i915.ko can still be loaded on such
2302          * old systems without an AcpiOpRegion.
2303          *
2304          * acpi_video_register() will report -ENODEV later as well due
2305          * to acpi_disabled when i915.ko tries to register itself afterwards.
2306          */
2307         if (acpi_disabled)
2308                 return 0;
2309
2310         if (intel_opregion_present())
2311                 return 0;
2312
2313         return acpi_video_register();
2314 }
2315
2316 static void __exit acpi_video_exit(void)
2317 {
2318         acpi_video_detect_exit();
2319         acpi_video_unregister();
2320
2321         return;
2322 }
2323
2324 module_init(acpi_video_init);
2325 module_exit(acpi_video_exit);