ACPI / video: ignore BIOS initial backlight value for HP Pavilion g6
[linux-3.10.git] / drivers / acpi / video.c
1 /*
2  *  video.c - ACPI Video Driver ($Revision:$)
3  *
4  *  Copyright (C) 2004 Luming Yu <luming.yu@intel.com>
5  *  Copyright (C) 2004 Bruno Ducrot <ducrot@poupinou.org>
6  *  Copyright (C) 2006 Thomas Tuttle <linux-kernel@ttuttle.net>
7  *
8  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9  *
10  *  This program is free software; you can redistribute it and/or modify
11  *  it under the terms of the GNU General Public License as published by
12  *  the Free Software Foundation; either version 2 of the License, or (at
13  *  your option) any later version.
14  *
15  *  This program is distributed in the hope that it will be useful, but
16  *  WITHOUT ANY WARRANTY; without even the implied warranty of
17  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
18  *  General Public License for more details.
19  *
20  *  You should have received a copy of the GNU General Public License along
21  *  with this program; if not, write to the Free Software Foundation, Inc.,
22  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
23  *
24  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
25  */
26
27 #include <linux/kernel.h>
28 #include <linux/module.h>
29 #include <linux/init.h>
30 #include <linux/types.h>
31 #include <linux/list.h>
32 #include <linux/mutex.h>
33 #include <linux/input.h>
34 #include <linux/backlight.h>
35 #include <linux/thermal.h>
36 #include <linux/sort.h>
37 #include <linux/pci.h>
38 #include <linux/pci_ids.h>
39 #include <linux/slab.h>
40 #include <asm/uaccess.h>
41 #include <linux/dmi.h>
42 #include <acpi/acpi_bus.h>
43 #include <acpi/acpi_drivers.h>
44 #include <linux/suspend.h>
45 #include <acpi/video.h>
46
47 #define PREFIX "ACPI: "
48
49 #define ACPI_VIDEO_BUS_NAME             "Video Bus"
50 #define ACPI_VIDEO_DEVICE_NAME          "Video Device"
51 #define ACPI_VIDEO_NOTIFY_SWITCH        0x80
52 #define ACPI_VIDEO_NOTIFY_PROBE         0x81
53 #define ACPI_VIDEO_NOTIFY_CYCLE         0x82
54 #define ACPI_VIDEO_NOTIFY_NEXT_OUTPUT   0x83
55 #define ACPI_VIDEO_NOTIFY_PREV_OUTPUT   0x84
56
57 #define ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS      0x85
58 #define ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS        0x86
59 #define ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS        0x87
60 #define ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS       0x88
61 #define ACPI_VIDEO_NOTIFY_DISPLAY_OFF           0x89
62
63 #define MAX_NAME_LEN    20
64
65 #define _COMPONENT              ACPI_VIDEO_COMPONENT
66 ACPI_MODULE_NAME("video");
67
68 MODULE_AUTHOR("Bruno Ducrot");
69 MODULE_DESCRIPTION("ACPI Video Driver");
70 MODULE_LICENSE("GPL");
71
72 static bool brightness_switch_enabled = 1;
73 module_param(brightness_switch_enabled, bool, 0644);
74
75 /*
76  * By default, we don't allow duplicate ACPI video bus devices
77  * under the same VGA controller
78  */
79 static bool allow_duplicates;
80 module_param(allow_duplicates, bool, 0644);
81
82 /*
83  * Some BIOSes claim they use minimum backlight at boot,
84  * and this may bring dimming screen after boot
85  */
86 static bool use_bios_initial_backlight = 1;
87 module_param(use_bios_initial_backlight, bool, 0644);
88
89 static int register_count = 0;
90 static int acpi_video_bus_add(struct acpi_device *device);
91 static int acpi_video_bus_remove(struct acpi_device *device);
92 static void acpi_video_bus_notify(struct acpi_device *device, u32 event);
93
94 static const struct acpi_device_id video_device_ids[] = {
95         {ACPI_VIDEO_HID, 0},
96         {"", 0},
97 };
98 MODULE_DEVICE_TABLE(acpi, video_device_ids);
99
100 static struct acpi_driver acpi_video_bus = {
101         .name = "video",
102         .class = ACPI_VIDEO_CLASS,
103         .ids = video_device_ids,
104         .ops = {
105                 .add = acpi_video_bus_add,
106                 .remove = acpi_video_bus_remove,
107                 .notify = acpi_video_bus_notify,
108                 },
109 };
110
111 struct acpi_video_bus_flags {
112         u8 multihead:1;         /* can switch video heads */
113         u8 rom:1;               /* can retrieve a video rom */
114         u8 post:1;              /* can configure the head to */
115         u8 reserved:5;
116 };
117
118 struct acpi_video_bus_cap {
119         u8 _DOS:1;              /*Enable/Disable output switching */
120         u8 _DOD:1;              /*Enumerate all devices attached to display adapter */
121         u8 _ROM:1;              /*Get ROM Data */
122         u8 _GPD:1;              /*Get POST Device */
123         u8 _SPD:1;              /*Set POST Device */
124         u8 _VPO:1;              /*Video POST Options */
125         u8 reserved:2;
126 };
127
128 struct acpi_video_device_attrib {
129         u32 display_index:4;    /* A zero-based instance of the Display */
130         u32 display_port_attachment:4;  /*This field differentiates the display type */
131         u32 display_type:4;     /*Describe the specific type in use */
132         u32 vendor_specific:4;  /*Chipset Vendor Specific */
133         u32 bios_can_detect:1;  /*BIOS can detect the device */
134         u32 depend_on_vga:1;    /*Non-VGA output device whose power is related to 
135                                    the VGA device. */
136         u32 pipe_id:3;          /*For VGA multiple-head devices. */
137         u32 reserved:10;        /*Must be 0 */
138         u32 device_id_scheme:1; /*Device ID Scheme */
139 };
140
141 struct acpi_video_enumerated_device {
142         union {
143                 u32 int_val;
144                 struct acpi_video_device_attrib attrib;
145         } value;
146         struct acpi_video_device *bind_info;
147 };
148
149 struct acpi_video_bus {
150         struct acpi_device *device;
151         u8 dos_setting;
152         struct acpi_video_enumerated_device *attached_array;
153         u8 attached_count;
154         struct acpi_video_bus_cap cap;
155         struct acpi_video_bus_flags flags;
156         struct list_head video_device_list;
157         struct mutex device_list_lock;  /* protects video_device_list */
158         struct input_dev *input;
159         char phys[32];  /* for input device */
160         struct notifier_block pm_nb;
161 };
162
163 struct acpi_video_device_flags {
164         u8 crt:1;
165         u8 lcd:1;
166         u8 tvout:1;
167         u8 dvi:1;
168         u8 bios:1;
169         u8 unknown:1;
170         u8 notify:1;
171         u8 reserved:1;
172 };
173
174 struct acpi_video_device_cap {
175         u8 _ADR:1;              /*Return the unique ID */
176         u8 _BCL:1;              /*Query list of brightness control levels supported */
177         u8 _BCM:1;              /*Set the brightness level */
178         u8 _BQC:1;              /* Get current brightness level */
179         u8 _BCQ:1;              /* Some buggy BIOS uses _BCQ instead of _BQC */
180         u8 _DDC:1;              /*Return the EDID for this device */
181 };
182
183 struct acpi_video_brightness_flags {
184         u8 _BCL_no_ac_battery_levels:1; /* no AC/Battery levels in _BCL */
185         u8 _BCL_reversed:1;             /* _BCL package is in a reversed order*/
186         u8 _BCL_use_index:1;            /* levels in _BCL are index values */
187         u8 _BCM_use_index:1;            /* input of _BCM is an index value */
188         u8 _BQC_use_index:1;            /* _BQC returns an index value */
189 };
190
191 struct acpi_video_device_brightness {
192         int curr;
193         int count;
194         int *levels;
195         struct acpi_video_brightness_flags flags;
196 };
197
198 struct acpi_video_device {
199         unsigned long device_id;
200         struct acpi_video_device_flags flags;
201         struct acpi_video_device_cap cap;
202         struct list_head entry;
203         struct acpi_video_bus *video;
204         struct acpi_device *dev;
205         struct acpi_video_device_brightness *brightness;
206         struct backlight_device *backlight;
207         struct thermal_cooling_device *cooling_dev;
208 };
209
210 static const char device_decode[][30] = {
211         "motherboard VGA device",
212         "PCI VGA device",
213         "AGP VGA device",
214         "UNKNOWN",
215 };
216
217 static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data);
218 static void acpi_video_device_rebind(struct acpi_video_bus *video);
219 static void acpi_video_device_bind(struct acpi_video_bus *video,
220                                    struct acpi_video_device *device);
221 static int acpi_video_device_enumerate(struct acpi_video_bus *video);
222 static int acpi_video_device_lcd_set_level(struct acpi_video_device *device,
223                         int level);
224 static int acpi_video_device_lcd_get_level_current(
225                         struct acpi_video_device *device,
226                         unsigned long long *level, bool raw);
227 static int acpi_video_get_next_level(struct acpi_video_device *device,
228                                      u32 level_current, u32 event);
229 static int acpi_video_switch_brightness(struct acpi_video_device *device,
230                                          int event);
231
232 /*backlight device sysfs support*/
233 static int acpi_video_get_brightness(struct backlight_device *bd)
234 {
235         unsigned long long cur_level;
236         int i;
237         struct acpi_video_device *vd =
238                 (struct acpi_video_device *)bl_get_data(bd);
239
240         if (acpi_video_device_lcd_get_level_current(vd, &cur_level, false))
241                 return -EINVAL;
242         for (i = 2; i < vd->brightness->count; i++) {
243                 if (vd->brightness->levels[i] == cur_level)
244                         /* The first two entries are special - see page 575
245                            of the ACPI spec 3.0 */
246                         return i-2;
247         }
248         return 0;
249 }
250
251 static int acpi_video_set_brightness(struct backlight_device *bd)
252 {
253         int request_level = bd->props.brightness + 2;
254         struct acpi_video_device *vd =
255                 (struct acpi_video_device *)bl_get_data(bd);
256
257         return acpi_video_device_lcd_set_level(vd,
258                                 vd->brightness->levels[request_level]);
259 }
260
261 static const struct backlight_ops acpi_backlight_ops = {
262         .get_brightness = acpi_video_get_brightness,
263         .update_status  = acpi_video_set_brightness,
264 };
265
266 /* thermal cooling device callbacks */
267 static int video_get_max_state(struct thermal_cooling_device *cooling_dev, unsigned
268                                long *state)
269 {
270         struct acpi_device *device = cooling_dev->devdata;
271         struct acpi_video_device *video = acpi_driver_data(device);
272
273         *state = video->brightness->count - 3;
274         return 0;
275 }
276
277 static int video_get_cur_state(struct thermal_cooling_device *cooling_dev, unsigned
278                                long *state)
279 {
280         struct acpi_device *device = cooling_dev->devdata;
281         struct acpi_video_device *video = acpi_driver_data(device);
282         unsigned long long level;
283         int offset;
284
285         if (acpi_video_device_lcd_get_level_current(video, &level, false))
286                 return -EINVAL;
287         for (offset = 2; offset < video->brightness->count; offset++)
288                 if (level == video->brightness->levels[offset]) {
289                         *state = video->brightness->count - offset - 1;
290                         return 0;
291                 }
292
293         return -EINVAL;
294 }
295
296 static int
297 video_set_cur_state(struct thermal_cooling_device *cooling_dev, unsigned long state)
298 {
299         struct acpi_device *device = cooling_dev->devdata;
300         struct acpi_video_device *video = acpi_driver_data(device);
301         int level;
302
303         if ( state >= video->brightness->count - 2)
304                 return -EINVAL;
305
306         state = video->brightness->count - state;
307         level = video->brightness->levels[state -1];
308         return acpi_video_device_lcd_set_level(video, level);
309 }
310
311 static const struct thermal_cooling_device_ops video_cooling_ops = {
312         .get_max_state = video_get_max_state,
313         .get_cur_state = video_get_cur_state,
314         .set_cur_state = video_set_cur_state,
315 };
316
317 /* --------------------------------------------------------------------------
318                                Video Management
319    -------------------------------------------------------------------------- */
320
321 static int
322 acpi_video_device_lcd_query_levels(struct acpi_video_device *device,
323                                    union acpi_object **levels)
324 {
325         int status;
326         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
327         union acpi_object *obj;
328
329
330         *levels = NULL;
331
332         status = acpi_evaluate_object(device->dev->handle, "_BCL", NULL, &buffer);
333         if (!ACPI_SUCCESS(status))
334                 return status;
335         obj = (union acpi_object *)buffer.pointer;
336         if (!obj || (obj->type != ACPI_TYPE_PACKAGE)) {
337                 printk(KERN_ERR PREFIX "Invalid _BCL data\n");
338                 status = -EFAULT;
339                 goto err;
340         }
341
342         *levels = obj;
343
344         return 0;
345
346       err:
347         kfree(buffer.pointer);
348
349         return status;
350 }
351
352 static int
353 acpi_video_device_lcd_set_level(struct acpi_video_device *device, int level)
354 {
355         int status;
356         union acpi_object arg0 = { ACPI_TYPE_INTEGER };
357         struct acpi_object_list args = { 1, &arg0 };
358         int state;
359
360         arg0.integer.value = level;
361
362         status = acpi_evaluate_object(device->dev->handle, "_BCM",
363                                       &args, NULL);
364         if (ACPI_FAILURE(status)) {
365                 ACPI_ERROR((AE_INFO, "Evaluating _BCM failed"));
366                 return -EIO;
367         }
368
369         device->brightness->curr = level;
370         for (state = 2; state < device->brightness->count; state++)
371                 if (level == device->brightness->levels[state]) {
372                         if (device->backlight)
373                                 device->backlight->props.brightness = state - 2;
374                         return 0;
375                 }
376
377         ACPI_ERROR((AE_INFO, "Current brightness invalid"));
378         return -EINVAL;
379 }
380
381 /*
382  * For some buggy _BQC methods, we need to add a constant value to
383  * the _BQC return value to get the actual current brightness level
384  */
385
386 static int bqc_offset_aml_bug_workaround;
387 static int __init video_set_bqc_offset(const struct dmi_system_id *d)
388 {
389         bqc_offset_aml_bug_workaround = 9;
390         return 0;
391 }
392
393 static int video_ignore_initial_backlight(const struct dmi_system_id *d)
394 {
395         use_bios_initial_backlight = 0;
396         return 0;
397 }
398
399 static struct dmi_system_id video_dmi_table[] __initdata = {
400         /*
401          * Broken _BQC workaround http://bugzilla.kernel.org/show_bug.cgi?id=13121
402          */
403         {
404          .callback = video_set_bqc_offset,
405          .ident = "Acer Aspire 5720",
406          .matches = {
407                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
408                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5720"),
409                 },
410         },
411         {
412          .callback = video_set_bqc_offset,
413          .ident = "Acer Aspire 5710Z",
414          .matches = {
415                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
416                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5710Z"),
417                 },
418         },
419         {
420          .callback = video_set_bqc_offset,
421          .ident = "eMachines E510",
422          .matches = {
423                 DMI_MATCH(DMI_BOARD_VENDOR, "EMACHINES"),
424                 DMI_MATCH(DMI_PRODUCT_NAME, "eMachines E510"),
425                 },
426         },
427         {
428          .callback = video_set_bqc_offset,
429          .ident = "Acer Aspire 5315",
430          .matches = {
431                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
432                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5315"),
433                 },
434         },
435         {
436          .callback = video_set_bqc_offset,
437          .ident = "Acer Aspire 7720",
438          .matches = {
439                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
440                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 7720"),
441                 },
442         },
443         {
444          .callback = video_ignore_initial_backlight,
445          .ident = "HP Folio 13-2000",
446          .matches = {
447                 DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
448                 DMI_MATCH(DMI_PRODUCT_NAME, "HP Folio 13 - 2000 Notebook PC"),
449                 },
450         },
451         {
452          .callback = video_ignore_initial_backlight,
453          .ident = "HP Pavilion dm4",
454          .matches = {
455                 DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
456                 DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion dm4 Notebook PC"),
457                 },
458         },
459         {
460          .callback = video_ignore_initial_backlight,
461          .ident = "HP Pavilion g6 Notebook PC",
462          .matches = {
463                  DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
464                  DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion g6 Notebook PC"),
465                 },
466         },
467         {
468          .callback = video_ignore_initial_backlight,
469          .ident = "HP 1000 Notebook PC",
470          .matches = {
471                 DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
472                 DMI_MATCH(DMI_PRODUCT_NAME, "HP 1000 Notebook PC"),
473                 },
474         },
475         {
476          .callback = video_ignore_initial_backlight,
477          .ident = "HP Pavilion m4",
478          .matches = {
479                 DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
480                 DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion m4 Notebook PC"),
481                 },
482         },
483         {}
484 };
485
486 static unsigned long long
487 acpi_video_bqc_value_to_level(struct acpi_video_device *device,
488                               unsigned long long bqc_value)
489 {
490         unsigned long long level;
491
492         if (device->brightness->flags._BQC_use_index) {
493                 /*
494                  * _BQC returns an index that doesn't account for
495                  * the first 2 items with special meaning, so we need
496                  * to compensate for that by offsetting ourselves
497                  */
498                 if (device->brightness->flags._BCL_reversed)
499                         bqc_value = device->brightness->count - 3 - bqc_value;
500
501                 level = device->brightness->levels[bqc_value + 2];
502         } else {
503                 level = bqc_value;
504         }
505
506         level += bqc_offset_aml_bug_workaround;
507
508         return level;
509 }
510
511 static int
512 acpi_video_device_lcd_get_level_current(struct acpi_video_device *device,
513                                         unsigned long long *level, bool raw)
514 {
515         acpi_status status = AE_OK;
516         int i;
517
518         if (device->cap._BQC || device->cap._BCQ) {
519                 char *buf = device->cap._BQC ? "_BQC" : "_BCQ";
520
521                 status = acpi_evaluate_integer(device->dev->handle, buf,
522                                                 NULL, level);
523                 if (ACPI_SUCCESS(status)) {
524                         if (raw) {
525                                 /*
526                                  * Caller has indicated he wants the raw
527                                  * value returned by _BQC, so don't furtherly
528                                  * mess with the value.
529                                  */
530                                 return 0;
531                         }
532
533                         *level = acpi_video_bqc_value_to_level(device, *level);
534
535                         for (i = 2; i < device->brightness->count; i++)
536                                 if (device->brightness->levels[i] == *level) {
537                                         device->brightness->curr = *level;
538                                         return 0;
539                         }
540                         /*
541                          * BQC returned an invalid level.
542                          * Stop using it.
543                          */
544                         ACPI_WARNING((AE_INFO,
545                                       "%s returned an invalid level",
546                                       buf));
547                         device->cap._BQC = device->cap._BCQ = 0;
548                 } else {
549                         /* Fixme:
550                          * should we return an error or ignore this failure?
551                          * dev->brightness->curr is a cached value which stores
552                          * the correct current backlight level in most cases.
553                          * ACPI video backlight still works w/ buggy _BQC.
554                          * http://bugzilla.kernel.org/show_bug.cgi?id=12233
555                          */
556                         ACPI_WARNING((AE_INFO, "Evaluating %s failed", buf));
557                         device->cap._BQC = device->cap._BCQ = 0;
558                 }
559         }
560
561         *level = device->brightness->curr;
562         return 0;
563 }
564
565 static int
566 acpi_video_device_EDID(struct acpi_video_device *device,
567                        union acpi_object **edid, ssize_t length)
568 {
569         int status;
570         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
571         union acpi_object *obj;
572         union acpi_object arg0 = { ACPI_TYPE_INTEGER };
573         struct acpi_object_list args = { 1, &arg0 };
574
575
576         *edid = NULL;
577
578         if (!device)
579                 return -ENODEV;
580         if (length == 128)
581                 arg0.integer.value = 1;
582         else if (length == 256)
583                 arg0.integer.value = 2;
584         else
585                 return -EINVAL;
586
587         status = acpi_evaluate_object(device->dev->handle, "_DDC", &args, &buffer);
588         if (ACPI_FAILURE(status))
589                 return -ENODEV;
590
591         obj = buffer.pointer;
592
593         if (obj && obj->type == ACPI_TYPE_BUFFER)
594                 *edid = obj;
595         else {
596                 printk(KERN_ERR PREFIX "Invalid _DDC data\n");
597                 status = -EFAULT;
598                 kfree(obj);
599         }
600
601         return status;
602 }
603
604 /* bus */
605
606 /*
607  *  Arg:
608  *      video           : video bus device pointer
609  *      bios_flag       : 
610  *              0.      The system BIOS should NOT automatically switch(toggle)
611  *                      the active display output.
612  *              1.      The system BIOS should automatically switch (toggle) the
613  *                      active display output. No switch event.
614  *              2.      The _DGS value should be locked.
615  *              3.      The system BIOS should not automatically switch (toggle) the
616  *                      active display output, but instead generate the display switch
617  *                      event notify code.
618  *      lcd_flag        :
619  *              0.      The system BIOS should automatically control the brightness level
620  *                      of the LCD when the power changes from AC to DC
621  *              1.      The system BIOS should NOT automatically control the brightness 
622  *                      level of the LCD when the power changes from AC to DC.
623  * Return Value:
624  *              -EINVAL wrong arg.
625  */
626
627 static int
628 acpi_video_bus_DOS(struct acpi_video_bus *video, int bios_flag, int lcd_flag)
629 {
630         acpi_status status;
631         union acpi_object arg0 = { ACPI_TYPE_INTEGER };
632         struct acpi_object_list args = { 1, &arg0 };
633
634         if (!video->cap._DOS)
635                 return 0;
636
637         if (bios_flag < 0 || bios_flag > 3 || lcd_flag < 0 || lcd_flag > 1)
638                 return -EINVAL;
639         arg0.integer.value = (lcd_flag << 2) | bios_flag;
640         video->dos_setting = arg0.integer.value;
641         status = acpi_evaluate_object(video->device->handle, "_DOS",
642                 &args, NULL);
643         if (ACPI_FAILURE(status))
644                 return -EIO;
645
646         return 0;
647 }
648
649 /*
650  * Simple comparison function used to sort backlight levels.
651  */
652
653 static int
654 acpi_video_cmp_level(const void *a, const void *b)
655 {
656         return *(int *)a - *(int *)b;
657 }
658
659 /*
660  * Decides if _BQC/_BCQ for this system is usable
661  *
662  * We do this by changing the level first and then read out the current
663  * brightness level, if the value does not match, find out if it is using
664  * index. If not, clear the _BQC/_BCQ capability.
665  */
666 static int acpi_video_bqc_quirk(struct acpi_video_device *device,
667                                 int max_level, int current_level)
668 {
669         struct acpi_video_device_brightness *br = device->brightness;
670         int result;
671         unsigned long long level;
672         int test_level;
673
674         /* don't mess with existing known broken systems */
675         if (bqc_offset_aml_bug_workaround)
676                 return 0;
677
678         /*
679          * Some systems always report current brightness level as maximum
680          * through _BQC, we need to test another value for them.
681          */
682         test_level = current_level == max_level ? br->levels[2] : max_level;
683
684         result = acpi_video_device_lcd_set_level(device, test_level);
685         if (result)
686                 return result;
687
688         result = acpi_video_device_lcd_get_level_current(device, &level, true);
689         if (result)
690                 return result;
691
692         if (level != test_level) {
693                 /* buggy _BQC found, need to find out if it uses index */
694                 if (level < br->count) {
695                         if (br->flags._BCL_reversed)
696                                 level = br->count - 3 - level;
697                         if (br->levels[level + 2] == test_level)
698                                 br->flags._BQC_use_index = 1;
699                 }
700
701                 if (!br->flags._BQC_use_index)
702                         device->cap._BQC = device->cap._BCQ = 0;
703         }
704
705         return 0;
706 }
707
708
709 /*
710  *  Arg:        
711  *      device  : video output device (LCD, CRT, ..)
712  *
713  *  Return Value:
714  *      Maximum brightness level
715  *
716  *  Allocate and initialize device->brightness.
717  */
718
719 static int
720 acpi_video_init_brightness(struct acpi_video_device *device)
721 {
722         union acpi_object *obj = NULL;
723         int i, max_level = 0, count = 0, level_ac_battery = 0;
724         unsigned long long level, level_old;
725         union acpi_object *o;
726         struct acpi_video_device_brightness *br = NULL;
727         int result = -EINVAL;
728
729         if (!ACPI_SUCCESS(acpi_video_device_lcd_query_levels(device, &obj))) {
730                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Could not query available "
731                                                 "LCD brightness level\n"));
732                 goto out;
733         }
734
735         if (obj->package.count < 2)
736                 goto out;
737
738         br = kzalloc(sizeof(*br), GFP_KERNEL);
739         if (!br) {
740                 printk(KERN_ERR "can't allocate memory\n");
741                 result = -ENOMEM;
742                 goto out;
743         }
744
745         br->levels = kmalloc((obj->package.count + 2) * sizeof *(br->levels),
746                                 GFP_KERNEL);
747         if (!br->levels) {
748                 result = -ENOMEM;
749                 goto out_free;
750         }
751
752         for (i = 0; i < obj->package.count; i++) {
753                 o = (union acpi_object *)&obj->package.elements[i];
754                 if (o->type != ACPI_TYPE_INTEGER) {
755                         printk(KERN_ERR PREFIX "Invalid data\n");
756                         continue;
757                 }
758                 br->levels[count] = (u32) o->integer.value;
759
760                 if (br->levels[count] > max_level)
761                         max_level = br->levels[count];
762                 count++;
763         }
764
765         /*
766          * some buggy BIOS don't export the levels
767          * when machine is on AC/Battery in _BCL package.
768          * In this case, the first two elements in _BCL packages
769          * are also supported brightness levels that OS should take care of.
770          */
771         for (i = 2; i < count; i++) {
772                 if (br->levels[i] == br->levels[0])
773                         level_ac_battery++;
774                 if (br->levels[i] == br->levels[1])
775                         level_ac_battery++;
776         }
777
778         if (level_ac_battery < 2) {
779                 level_ac_battery = 2 - level_ac_battery;
780                 br->flags._BCL_no_ac_battery_levels = 1;
781                 for (i = (count - 1 + level_ac_battery); i >= 2; i--)
782                         br->levels[i] = br->levels[i - level_ac_battery];
783                 count += level_ac_battery;
784         } else if (level_ac_battery > 2)
785                 ACPI_ERROR((AE_INFO, "Too many duplicates in _BCL package"));
786
787         /* Check if the _BCL package is in a reversed order */
788         if (max_level == br->levels[2]) {
789                 br->flags._BCL_reversed = 1;
790                 sort(&br->levels[2], count - 2, sizeof(br->levels[2]),
791                         acpi_video_cmp_level, NULL);
792         } else if (max_level != br->levels[count - 1])
793                 ACPI_ERROR((AE_INFO,
794                             "Found unordered _BCL package"));
795
796         br->count = count;
797         device->brightness = br;
798
799         /* Check the input/output of _BQC/_BCL/_BCM */
800         if ((max_level < 100) && (max_level <= (count - 2)))
801                 br->flags._BCL_use_index = 1;
802
803         /*
804          * _BCM is always consistent with _BCL,
805          * at least for all the laptops we have ever seen.
806          */
807         br->flags._BCM_use_index = br->flags._BCL_use_index;
808
809         /* _BQC uses INDEX while _BCL uses VALUE in some laptops */
810         br->curr = level = max_level;
811
812         if (!device->cap._BQC)
813                 goto set_level;
814
815         result = acpi_video_device_lcd_get_level_current(device,
816                                                          &level_old, true);
817         if (result)
818                 goto out_free_levels;
819
820         result = acpi_video_bqc_quirk(device, max_level, level_old);
821         if (result)
822                 goto out_free_levels;
823         /*
824          * cap._BQC may get cleared due to _BQC is found to be broken
825          * in acpi_video_bqc_quirk, so check again here.
826          */
827         if (!device->cap._BQC)
828                 goto set_level;
829
830         if (use_bios_initial_backlight) {
831                 level = acpi_video_bqc_value_to_level(device, level_old);
832                 /*
833                  * On some buggy laptops, _BQC returns an uninitialized
834                  * value when invoked for the first time, i.e.
835                  * level_old is invalid (no matter whether it's a level
836                  * or an index). Set the backlight to max_level in this case.
837                  */
838                 for (i = 2; i < br->count; i++)
839                         if (level_old == br->levels[i])
840                                 break;
841                 if (i == br->count)
842                         level = max_level;
843         }
844
845 set_level:
846         result = acpi_video_device_lcd_set_level(device, level);
847         if (result)
848                 goto out_free_levels;
849
850         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
851                           "found %d brightness levels\n", count - 2));
852         kfree(obj);
853         return result;
854
855 out_free_levels:
856         kfree(br->levels);
857 out_free:
858         kfree(br);
859 out:
860         device->brightness = NULL;
861         kfree(obj);
862         return result;
863 }
864
865 /*
866  *  Arg:
867  *      device  : video output device (LCD, CRT, ..)
868  *
869  *  Return Value:
870  *      None
871  *
872  *  Find out all required AML methods defined under the output
873  *  device.
874  */
875
876 static void acpi_video_device_find_cap(struct acpi_video_device *device)
877 {
878         acpi_handle h_dummy1;
879
880         if (ACPI_SUCCESS(acpi_get_handle(device->dev->handle, "_ADR", &h_dummy1))) {
881                 device->cap._ADR = 1;
882         }
883         if (ACPI_SUCCESS(acpi_get_handle(device->dev->handle, "_BCL", &h_dummy1))) {
884                 device->cap._BCL = 1;
885         }
886         if (ACPI_SUCCESS(acpi_get_handle(device->dev->handle, "_BCM", &h_dummy1))) {
887                 device->cap._BCM = 1;
888         }
889         if (ACPI_SUCCESS(acpi_get_handle(device->dev->handle,"_BQC",&h_dummy1)))
890                 device->cap._BQC = 1;
891         else if (ACPI_SUCCESS(acpi_get_handle(device->dev->handle, "_BCQ",
892                                 &h_dummy1))) {
893                 printk(KERN_WARNING FW_BUG "_BCQ is used instead of _BQC\n");
894                 device->cap._BCQ = 1;
895         }
896
897         if (ACPI_SUCCESS(acpi_get_handle(device->dev->handle, "_DDC", &h_dummy1))) {
898                 device->cap._DDC = 1;
899         }
900
901         if (acpi_video_backlight_support()) {
902                 struct backlight_properties props;
903                 struct pci_dev *pdev;
904                 acpi_handle acpi_parent;
905                 struct device *parent = NULL;
906                 int result;
907                 static int count = 0;
908                 char *name;
909
910                 result = acpi_video_init_brightness(device);
911                 if (result)
912                         return;
913                 name = kasprintf(GFP_KERNEL, "acpi_video%d", count);
914                 if (!name)
915                         return;
916                 count++;
917
918                 acpi_get_parent(device->dev->handle, &acpi_parent);
919
920                 pdev = acpi_get_pci_dev(acpi_parent);
921                 if (pdev) {
922                         parent = &pdev->dev;
923                         pci_dev_put(pdev);
924                 }
925
926                 memset(&props, 0, sizeof(struct backlight_properties));
927                 props.type = BACKLIGHT_FIRMWARE;
928                 props.max_brightness = device->brightness->count - 3;
929                 device->backlight = backlight_device_register(name,
930                                                               parent,
931                                                               device,
932                                                               &acpi_backlight_ops,
933                                                               &props);
934                 kfree(name);
935                 if (IS_ERR(device->backlight))
936                         return;
937
938                 /*
939                  * Save current brightness level in case we have to restore it
940                  * before acpi_video_device_lcd_set_level() is called next time.
941                  */
942                 device->backlight->props.brightness =
943                                 acpi_video_get_brightness(device->backlight);
944
945                 device->cooling_dev = thermal_cooling_device_register("LCD",
946                                         device->dev, &video_cooling_ops);
947                 if (IS_ERR(device->cooling_dev)) {
948                         /*
949                          * Set cooling_dev to NULL so we don't crash trying to
950                          * free it.
951                          * Also, why the hell we are returning early and
952                          * not attempt to register video output if cooling
953                          * device registration failed?
954                          * -- dtor
955                          */
956                         device->cooling_dev = NULL;
957                         return;
958                 }
959
960                 dev_info(&device->dev->dev, "registered as cooling_device%d\n",
961                          device->cooling_dev->id);
962                 result = sysfs_create_link(&device->dev->dev.kobj,
963                                 &device->cooling_dev->device.kobj,
964                                 "thermal_cooling");
965                 if (result)
966                         printk(KERN_ERR PREFIX "Create sysfs link\n");
967                 result = sysfs_create_link(&device->cooling_dev->device.kobj,
968                                 &device->dev->dev.kobj, "device");
969                 if (result)
970                         printk(KERN_ERR PREFIX "Create sysfs link\n");
971
972         }
973 }
974
975 /*
976  *  Arg:        
977  *      device  : video output device (VGA)
978  *
979  *  Return Value:
980  *      None
981  *
982  *  Find out all required AML methods defined under the video bus device.
983  */
984
985 static void acpi_video_bus_find_cap(struct acpi_video_bus *video)
986 {
987         acpi_handle h_dummy1;
988
989         if (ACPI_SUCCESS(acpi_get_handle(video->device->handle, "_DOS", &h_dummy1))) {
990                 video->cap._DOS = 1;
991         }
992         if (ACPI_SUCCESS(acpi_get_handle(video->device->handle, "_DOD", &h_dummy1))) {
993                 video->cap._DOD = 1;
994         }
995         if (ACPI_SUCCESS(acpi_get_handle(video->device->handle, "_ROM", &h_dummy1))) {
996                 video->cap._ROM = 1;
997         }
998         if (ACPI_SUCCESS(acpi_get_handle(video->device->handle, "_GPD", &h_dummy1))) {
999                 video->cap._GPD = 1;
1000         }
1001         if (ACPI_SUCCESS(acpi_get_handle(video->device->handle, "_SPD", &h_dummy1))) {
1002                 video->cap._SPD = 1;
1003         }
1004         if (ACPI_SUCCESS(acpi_get_handle(video->device->handle, "_VPO", &h_dummy1))) {
1005                 video->cap._VPO = 1;
1006         }
1007 }
1008
1009 /*
1010  * Check whether the video bus device has required AML method to
1011  * support the desired features
1012  */
1013
1014 static int acpi_video_bus_check(struct acpi_video_bus *video)
1015 {
1016         acpi_status status = -ENOENT;
1017         struct pci_dev *dev;
1018
1019         if (!video)
1020                 return -EINVAL;
1021
1022         dev = acpi_get_pci_dev(video->device->handle);
1023         if (!dev)
1024                 return -ENODEV;
1025         pci_dev_put(dev);
1026
1027         /* Since there is no HID, CID and so on for VGA driver, we have
1028          * to check well known required nodes.
1029          */
1030
1031         /* Does this device support video switching? */
1032         if (video->cap._DOS || video->cap._DOD) {
1033                 if (!video->cap._DOS) {
1034                         printk(KERN_WARNING FW_BUG
1035                                 "ACPI(%s) defines _DOD but not _DOS\n",
1036                                 acpi_device_bid(video->device));
1037                 }
1038                 video->flags.multihead = 1;
1039                 status = 0;
1040         }
1041
1042         /* Does this device support retrieving a video ROM? */
1043         if (video->cap._ROM) {
1044                 video->flags.rom = 1;
1045                 status = 0;
1046         }
1047
1048         /* Does this device support configuring which video device to POST? */
1049         if (video->cap._GPD && video->cap._SPD && video->cap._VPO) {
1050                 video->flags.post = 1;
1051                 status = 0;
1052         }
1053
1054         return status;
1055 }
1056
1057 /* --------------------------------------------------------------------------
1058                                  Driver Interface
1059    -------------------------------------------------------------------------- */
1060
1061 /* device interface */
1062 static struct acpi_video_device_attrib*
1063 acpi_video_get_device_attr(struct acpi_video_bus *video, unsigned long device_id)
1064 {
1065         struct acpi_video_enumerated_device *ids;
1066         int i;
1067
1068         for (i = 0; i < video->attached_count; i++) {
1069                 ids = &video->attached_array[i];
1070                 if ((ids->value.int_val & 0xffff) == device_id)
1071                         return &ids->value.attrib;
1072         }
1073
1074         return NULL;
1075 }
1076
1077 static int
1078 acpi_video_get_device_type(struct acpi_video_bus *video,
1079                            unsigned long device_id)
1080 {
1081         struct acpi_video_enumerated_device *ids;
1082         int i;
1083
1084         for (i = 0; i < video->attached_count; i++) {
1085                 ids = &video->attached_array[i];
1086                 if ((ids->value.int_val & 0xffff) == device_id)
1087                         return ids->value.int_val;
1088         }
1089
1090         return 0;
1091 }
1092
1093 static int
1094 acpi_video_bus_get_one_device(struct acpi_device *device,
1095                               struct acpi_video_bus *video)
1096 {
1097         unsigned long long device_id;
1098         int status, device_type;
1099         struct acpi_video_device *data;
1100         struct acpi_video_device_attrib* attribute;
1101
1102         status =
1103             acpi_evaluate_integer(device->handle, "_ADR", NULL, &device_id);
1104         /* Some device omits _ADR, we skip them instead of fail */
1105         if (ACPI_FAILURE(status))
1106                 return 0;
1107
1108         data = kzalloc(sizeof(struct acpi_video_device), GFP_KERNEL);
1109         if (!data)
1110                 return -ENOMEM;
1111
1112         strcpy(acpi_device_name(device), ACPI_VIDEO_DEVICE_NAME);
1113         strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
1114         device->driver_data = data;
1115
1116         data->device_id = device_id;
1117         data->video = video;
1118         data->dev = device;
1119
1120         attribute = acpi_video_get_device_attr(video, device_id);
1121
1122         if((attribute != NULL) && attribute->device_id_scheme) {
1123                 switch (attribute->display_type) {
1124                 case ACPI_VIDEO_DISPLAY_CRT:
1125                         data->flags.crt = 1;
1126                         break;
1127                 case ACPI_VIDEO_DISPLAY_TV:
1128                         data->flags.tvout = 1;
1129                         break;
1130                 case ACPI_VIDEO_DISPLAY_DVI:
1131                         data->flags.dvi = 1;
1132                         break;
1133                 case ACPI_VIDEO_DISPLAY_LCD:
1134                         data->flags.lcd = 1;
1135                         break;
1136                 default:
1137                         data->flags.unknown = 1;
1138                         break;
1139                 }
1140                 if(attribute->bios_can_detect)
1141                         data->flags.bios = 1;
1142         } else {
1143                 /* Check for legacy IDs */
1144                 device_type = acpi_video_get_device_type(video, device_id);
1145                 /* Ignore bits 16 and 18-20 */
1146                 switch (device_type & 0xffe2ffff) {
1147                         case ACPI_VIDEO_DISPLAY_LEGACY_MONITOR:
1148                                 data->flags.crt = 1;
1149                                 break;
1150                         case ACPI_VIDEO_DISPLAY_LEGACY_PANEL:
1151                                 data->flags.lcd = 1;
1152                                 break;
1153                         case ACPI_VIDEO_DISPLAY_LEGACY_TV:
1154                                 data->flags.tvout = 1;
1155                                 break;
1156                         default:
1157                                 data->flags.unknown = 1;
1158                 }
1159         }
1160
1161         acpi_video_device_bind(video, data);
1162         acpi_video_device_find_cap(data);
1163
1164         status = acpi_install_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
1165                                              acpi_video_device_notify, data);
1166         if (ACPI_FAILURE(status))
1167                 dev_err(&device->dev, "Error installing notify handler\n");
1168         else
1169                 data->flags.notify = 1;
1170
1171         mutex_lock(&video->device_list_lock);
1172         list_add_tail(&data->entry, &video->video_device_list);
1173         mutex_unlock(&video->device_list_lock);
1174
1175         return status;
1176 }
1177
1178 /*
1179  *  Arg:
1180  *      video   : video bus device 
1181  *
1182  *  Return:
1183  *      none
1184  *  
1185  *  Enumerate the video device list of the video bus, 
1186  *  bind the ids with the corresponding video devices
1187  *  under the video bus.
1188  */
1189
1190 static void acpi_video_device_rebind(struct acpi_video_bus *video)
1191 {
1192         struct acpi_video_device *dev;
1193
1194         mutex_lock(&video->device_list_lock);
1195
1196         list_for_each_entry(dev, &video->video_device_list, entry)
1197                 acpi_video_device_bind(video, dev);
1198
1199         mutex_unlock(&video->device_list_lock);
1200 }
1201
1202 /*
1203  *  Arg:
1204  *      video   : video bus device 
1205  *      device  : video output device under the video 
1206  *              bus
1207  *
1208  *  Return:
1209  *      none
1210  *  
1211  *  Bind the ids with the corresponding video devices
1212  *  under the video bus.
1213  */
1214
1215 static void
1216 acpi_video_device_bind(struct acpi_video_bus *video,
1217                        struct acpi_video_device *device)
1218 {
1219         struct acpi_video_enumerated_device *ids;
1220         int i;
1221
1222         for (i = 0; i < video->attached_count; i++) {
1223                 ids = &video->attached_array[i];
1224                 if (device->device_id == (ids->value.int_val & 0xffff)) {
1225                         ids->bind_info = device;
1226                         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "device_bind %d\n", i));
1227                 }
1228         }
1229 }
1230
1231 /*
1232  *  Arg:
1233  *      video   : video bus device 
1234  *
1235  *  Return:
1236  *      < 0     : error
1237  *  
1238  *  Call _DOD to enumerate all devices attached to display adapter
1239  *
1240  */
1241
1242 static int acpi_video_device_enumerate(struct acpi_video_bus *video)
1243 {
1244         int status;
1245         int count;
1246         int i;
1247         struct acpi_video_enumerated_device *active_list;
1248         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1249         union acpi_object *dod = NULL;
1250         union acpi_object *obj;
1251
1252         status = acpi_evaluate_object(video->device->handle, "_DOD", NULL, &buffer);
1253         if (!ACPI_SUCCESS(status)) {
1254                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _DOD"));
1255                 return status;
1256         }
1257
1258         dod = buffer.pointer;
1259         if (!dod || (dod->type != ACPI_TYPE_PACKAGE)) {
1260                 ACPI_EXCEPTION((AE_INFO, status, "Invalid _DOD data"));
1261                 status = -EFAULT;
1262                 goto out;
1263         }
1264
1265         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d video heads in _DOD\n",
1266                           dod->package.count));
1267
1268         active_list = kcalloc(1 + dod->package.count,
1269                               sizeof(struct acpi_video_enumerated_device),
1270                               GFP_KERNEL);
1271         if (!active_list) {
1272                 status = -ENOMEM;
1273                 goto out;
1274         }
1275
1276         count = 0;
1277         for (i = 0; i < dod->package.count; i++) {
1278                 obj = &dod->package.elements[i];
1279
1280                 if (obj->type != ACPI_TYPE_INTEGER) {
1281                         printk(KERN_ERR PREFIX
1282                                 "Invalid _DOD data in element %d\n", i);
1283                         continue;
1284                 }
1285
1286                 active_list[count].value.int_val = obj->integer.value;
1287                 active_list[count].bind_info = NULL;
1288                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "dod element[%d] = %d\n", i,
1289                                   (int)obj->integer.value));
1290                 count++;
1291         }
1292
1293         kfree(video->attached_array);
1294
1295         video->attached_array = active_list;
1296         video->attached_count = count;
1297
1298  out:
1299         kfree(buffer.pointer);
1300         return status;
1301 }
1302
1303 static int
1304 acpi_video_get_next_level(struct acpi_video_device *device,
1305                           u32 level_current, u32 event)
1306 {
1307         int min, max, min_above, max_below, i, l, delta = 255;
1308         max = max_below = 0;
1309         min = min_above = 255;
1310         /* Find closest level to level_current */
1311         for (i = 2; i < device->brightness->count; i++) {
1312                 l = device->brightness->levels[i];
1313                 if (abs(l - level_current) < abs(delta)) {
1314                         delta = l - level_current;
1315                         if (!delta)
1316                                 break;
1317                 }
1318         }
1319         /* Ajust level_current to closest available level */
1320         level_current += delta;
1321         for (i = 2; i < device->brightness->count; i++) {
1322                 l = device->brightness->levels[i];
1323                 if (l < min)
1324                         min = l;
1325                 if (l > max)
1326                         max = l;
1327                 if (l < min_above && l > level_current)
1328                         min_above = l;
1329                 if (l > max_below && l < level_current)
1330                         max_below = l;
1331         }
1332
1333         switch (event) {
1334         case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:
1335                 return (level_current < max) ? min_above : min;
1336         case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:
1337                 return (level_current < max) ? min_above : max;
1338         case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:
1339                 return (level_current > min) ? max_below : min;
1340         case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS:
1341         case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:
1342                 return 0;
1343         default:
1344                 return level_current;
1345         }
1346 }
1347
1348 static int
1349 acpi_video_switch_brightness(struct acpi_video_device *device, int event)
1350 {
1351         unsigned long long level_current, level_next;
1352         int result = -EINVAL;
1353
1354         /* no warning message if acpi_backlight=vendor is used */
1355         if (!acpi_video_backlight_support())
1356                 return 0;
1357
1358         if (!device->brightness)
1359                 goto out;
1360
1361         result = acpi_video_device_lcd_get_level_current(device,
1362                                                          &level_current,
1363                                                          false);
1364         if (result)
1365                 goto out;
1366
1367         level_next = acpi_video_get_next_level(device, level_current, event);
1368
1369         result = acpi_video_device_lcd_set_level(device, level_next);
1370
1371         if (!result)
1372                 backlight_force_update(device->backlight,
1373                                        BACKLIGHT_UPDATE_HOTKEY);
1374
1375 out:
1376         if (result)
1377                 printk(KERN_ERR PREFIX "Failed to switch the brightness\n");
1378
1379         return result;
1380 }
1381
1382 int acpi_video_get_edid(struct acpi_device *device, int type, int device_id,
1383                         void **edid)
1384 {
1385         struct acpi_video_bus *video;
1386         struct acpi_video_device *video_device;
1387         union acpi_object *buffer = NULL;
1388         acpi_status status;
1389         int i, length;
1390
1391         if (!device || !acpi_driver_data(device))
1392                 return -EINVAL;
1393
1394         video = acpi_driver_data(device);
1395
1396         for (i = 0; i < video->attached_count; i++) {
1397                 video_device = video->attached_array[i].bind_info;
1398                 length = 256;
1399
1400                 if (!video_device)
1401                         continue;
1402
1403                 if (!video_device->cap._DDC)
1404                         continue;
1405
1406                 if (type) {
1407                         switch (type) {
1408                         case ACPI_VIDEO_DISPLAY_CRT:
1409                                 if (!video_device->flags.crt)
1410                                         continue;
1411                                 break;
1412                         case ACPI_VIDEO_DISPLAY_TV:
1413                                 if (!video_device->flags.tvout)
1414                                         continue;
1415                                 break;
1416                         case ACPI_VIDEO_DISPLAY_DVI:
1417                                 if (!video_device->flags.dvi)
1418                                         continue;
1419                                 break;
1420                         case ACPI_VIDEO_DISPLAY_LCD:
1421                                 if (!video_device->flags.lcd)
1422                                         continue;
1423                                 break;
1424                         }
1425                 } else if (video_device->device_id != device_id) {
1426                         continue;
1427                 }
1428
1429                 status = acpi_video_device_EDID(video_device, &buffer, length);
1430
1431                 if (ACPI_FAILURE(status) || !buffer ||
1432                     buffer->type != ACPI_TYPE_BUFFER) {
1433                         length = 128;
1434                         status = acpi_video_device_EDID(video_device, &buffer,
1435                                                         length);
1436                         if (ACPI_FAILURE(status) || !buffer ||
1437                             buffer->type != ACPI_TYPE_BUFFER) {
1438                                 continue;
1439                         }
1440                 }
1441
1442                 *edid = buffer->buffer.pointer;
1443                 return length;
1444         }
1445
1446         return -ENODEV;
1447 }
1448 EXPORT_SYMBOL(acpi_video_get_edid);
1449
1450 static int
1451 acpi_video_bus_get_devices(struct acpi_video_bus *video,
1452                            struct acpi_device *device)
1453 {
1454         int status = 0;
1455         struct acpi_device *dev;
1456
1457         /*
1458          * There are systems where video module known to work fine regardless
1459          * of broken _DOD and ignoring returned value here doesn't cause
1460          * any issues later.
1461          */
1462         acpi_video_device_enumerate(video);
1463
1464         list_for_each_entry(dev, &device->children, node) {
1465
1466                 status = acpi_video_bus_get_one_device(dev, video);
1467                 if (status) {
1468                         dev_err(&dev->dev, "Can't attach device\n");
1469                         break;
1470                 }
1471         }
1472         return status;
1473 }
1474
1475 static int acpi_video_bus_put_one_device(struct acpi_video_device *device)
1476 {
1477         acpi_status status;
1478
1479         if (!device || !device->video)
1480                 return -ENOENT;
1481
1482         if (device->flags.notify) {
1483                 status = acpi_remove_notify_handler(device->dev->handle,
1484                                 ACPI_DEVICE_NOTIFY, acpi_video_device_notify);
1485                 if (ACPI_FAILURE(status))
1486                         dev_err(&device->dev->dev,
1487                                         "Can't remove video notify handler\n");
1488         }
1489
1490         if (device->backlight) {
1491                 backlight_device_unregister(device->backlight);
1492                 device->backlight = NULL;
1493         }
1494         if (device->cooling_dev) {
1495                 sysfs_remove_link(&device->dev->dev.kobj,
1496                                   "thermal_cooling");
1497                 sysfs_remove_link(&device->cooling_dev->device.kobj,
1498                                   "device");
1499                 thermal_cooling_device_unregister(device->cooling_dev);
1500                 device->cooling_dev = NULL;
1501         }
1502
1503         return 0;
1504 }
1505
1506 static int acpi_video_bus_put_devices(struct acpi_video_bus *video)
1507 {
1508         int status;
1509         struct acpi_video_device *dev, *next;
1510
1511         mutex_lock(&video->device_list_lock);
1512
1513         list_for_each_entry_safe(dev, next, &video->video_device_list, entry) {
1514
1515                 status = acpi_video_bus_put_one_device(dev);
1516                 if (ACPI_FAILURE(status))
1517                         printk(KERN_WARNING PREFIX
1518                                "hhuuhhuu bug in acpi video driver.\n");
1519
1520                 if (dev->brightness) {
1521                         kfree(dev->brightness->levels);
1522                         kfree(dev->brightness);
1523                 }
1524                 list_del(&dev->entry);
1525                 kfree(dev);
1526         }
1527
1528         mutex_unlock(&video->device_list_lock);
1529
1530         return 0;
1531 }
1532
1533 /* acpi_video interface */
1534
1535 static int acpi_video_bus_start_devices(struct acpi_video_bus *video)
1536 {
1537         return acpi_video_bus_DOS(video, 0, 0);
1538 }
1539
1540 static int acpi_video_bus_stop_devices(struct acpi_video_bus *video)
1541 {
1542         return acpi_video_bus_DOS(video, 0, 1);
1543 }
1544
1545 static void acpi_video_bus_notify(struct acpi_device *device, u32 event)
1546 {
1547         struct acpi_video_bus *video = acpi_driver_data(device);
1548         struct input_dev *input;
1549         int keycode = 0;
1550
1551         if (!video)
1552                 return;
1553
1554         input = video->input;
1555
1556         switch (event) {
1557         case ACPI_VIDEO_NOTIFY_SWITCH:  /* User requested a switch,
1558                                          * most likely via hotkey. */
1559                 acpi_bus_generate_proc_event(device, event, 0);
1560                 keycode = KEY_SWITCHVIDEOMODE;
1561                 break;
1562
1563         case ACPI_VIDEO_NOTIFY_PROBE:   /* User plugged in or removed a video
1564                                          * connector. */
1565                 acpi_video_device_enumerate(video);
1566                 acpi_video_device_rebind(video);
1567                 acpi_bus_generate_proc_event(device, event, 0);
1568                 keycode = KEY_SWITCHVIDEOMODE;
1569                 break;
1570
1571         case ACPI_VIDEO_NOTIFY_CYCLE:   /* Cycle Display output hotkey pressed. */
1572                 acpi_bus_generate_proc_event(device, event, 0);
1573                 keycode = KEY_SWITCHVIDEOMODE;
1574                 break;
1575         case ACPI_VIDEO_NOTIFY_NEXT_OUTPUT:     /* Next Display output hotkey pressed. */
1576                 acpi_bus_generate_proc_event(device, event, 0);
1577                 keycode = KEY_VIDEO_NEXT;
1578                 break;
1579         case ACPI_VIDEO_NOTIFY_PREV_OUTPUT:     /* previous Display output hotkey pressed. */
1580                 acpi_bus_generate_proc_event(device, event, 0);
1581                 keycode = KEY_VIDEO_PREV;
1582                 break;
1583
1584         default:
1585                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1586                                   "Unsupported event [0x%x]\n", event));
1587                 break;
1588         }
1589
1590         if (acpi_notifier_call_chain(device, event, 0))
1591                 /* Something vetoed the keypress. */
1592                 keycode = 0;
1593
1594         if (keycode) {
1595                 input_report_key(input, keycode, 1);
1596                 input_sync(input);
1597                 input_report_key(input, keycode, 0);
1598                 input_sync(input);
1599         }
1600
1601         return;
1602 }
1603
1604 static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data)
1605 {
1606         struct acpi_video_device *video_device = data;
1607         struct acpi_device *device = NULL;
1608         struct acpi_video_bus *bus;
1609         struct input_dev *input;
1610         int keycode = 0;
1611
1612         if (!video_device)
1613                 return;
1614
1615         device = video_device->dev;
1616         bus = video_device->video;
1617         input = bus->input;
1618
1619         switch (event) {
1620         case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:        /* Cycle brightness */
1621                 if (brightness_switch_enabled)
1622                         acpi_video_switch_brightness(video_device, event);
1623                 acpi_bus_generate_proc_event(device, event, 0);
1624                 keycode = KEY_BRIGHTNESS_CYCLE;
1625                 break;
1626         case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:  /* Increase brightness */
1627                 if (brightness_switch_enabled)
1628                         acpi_video_switch_brightness(video_device, event);
1629                 acpi_bus_generate_proc_event(device, event, 0);
1630                 keycode = KEY_BRIGHTNESSUP;
1631                 break;
1632         case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:  /* Decrease brightness */
1633                 if (brightness_switch_enabled)
1634                         acpi_video_switch_brightness(video_device, event);
1635                 acpi_bus_generate_proc_event(device, event, 0);
1636                 keycode = KEY_BRIGHTNESSDOWN;
1637                 break;
1638         case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS: /* zero brightness */
1639                 if (brightness_switch_enabled)
1640                         acpi_video_switch_brightness(video_device, event);
1641                 acpi_bus_generate_proc_event(device, event, 0);
1642                 keycode = KEY_BRIGHTNESS_ZERO;
1643                 break;
1644         case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:     /* display device off */
1645                 if (brightness_switch_enabled)
1646                         acpi_video_switch_brightness(video_device, event);
1647                 acpi_bus_generate_proc_event(device, event, 0);
1648                 keycode = KEY_DISPLAY_OFF;
1649                 break;
1650         default:
1651                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1652                                   "Unsupported event [0x%x]\n", event));
1653                 break;
1654         }
1655
1656         acpi_notifier_call_chain(device, event, 0);
1657
1658         if (keycode) {
1659                 input_report_key(input, keycode, 1);
1660                 input_sync(input);
1661                 input_report_key(input, keycode, 0);
1662                 input_sync(input);
1663         }
1664
1665         return;
1666 }
1667
1668 static int acpi_video_resume(struct notifier_block *nb,
1669                                 unsigned long val, void *ign)
1670 {
1671         struct acpi_video_bus *video;
1672         struct acpi_video_device *video_device;
1673         int i;
1674
1675         switch (val) {
1676         case PM_HIBERNATION_PREPARE:
1677         case PM_SUSPEND_PREPARE:
1678         case PM_RESTORE_PREPARE:
1679                 return NOTIFY_DONE;
1680         }
1681
1682         video = container_of(nb, struct acpi_video_bus, pm_nb);
1683
1684         dev_info(&video->device->dev, "Restoring backlight state\n");
1685
1686         for (i = 0; i < video->attached_count; i++) {
1687                 video_device = video->attached_array[i].bind_info;
1688                 if (video_device && video_device->backlight)
1689                         acpi_video_set_brightness(video_device->backlight);
1690         }
1691
1692         return NOTIFY_OK;
1693 }
1694
1695 static acpi_status
1696 acpi_video_bus_match(acpi_handle handle, u32 level, void *context,
1697                         void **return_value)
1698 {
1699         struct acpi_device *device = context;
1700         struct acpi_device *sibling;
1701         int result;
1702
1703         if (handle == device->handle)
1704                 return AE_CTRL_TERMINATE;
1705
1706         result = acpi_bus_get_device(handle, &sibling);
1707         if (result)
1708                 return AE_OK;
1709
1710         if (!strcmp(acpi_device_name(sibling), ACPI_VIDEO_BUS_NAME))
1711                         return AE_ALREADY_EXISTS;
1712
1713         return AE_OK;
1714 }
1715
1716 static int instance;
1717
1718 static int acpi_video_bus_add(struct acpi_device *device)
1719 {
1720         struct acpi_video_bus *video;
1721         struct input_dev *input;
1722         int error;
1723         acpi_status status;
1724
1725         status = acpi_walk_namespace(ACPI_TYPE_DEVICE,
1726                                 device->parent->handle, 1,
1727                                 acpi_video_bus_match, NULL,
1728                                 device, NULL);
1729         if (status == AE_ALREADY_EXISTS) {
1730                 printk(KERN_WARNING FW_BUG
1731                         "Duplicate ACPI video bus devices for the"
1732                         " same VGA controller, please try module "
1733                         "parameter \"video.allow_duplicates=1\""
1734                         "if the current driver doesn't work.\n");
1735                 if (!allow_duplicates)
1736                         return -ENODEV;
1737         }
1738
1739         video = kzalloc(sizeof(struct acpi_video_bus), GFP_KERNEL);
1740         if (!video)
1741                 return -ENOMEM;
1742
1743         /* a hack to fix the duplicate name "VID" problem on T61 */
1744         if (!strcmp(device->pnp.bus_id, "VID")) {
1745                 if (instance)
1746                         device->pnp.bus_id[3] = '0' + instance;
1747                 instance ++;
1748         }
1749         /* a hack to fix the duplicate name "VGA" problem on Pa 3553 */
1750         if (!strcmp(device->pnp.bus_id, "VGA")) {
1751                 if (instance)
1752                         device->pnp.bus_id[3] = '0' + instance;
1753                 instance++;
1754         }
1755
1756         video->device = device;
1757         strcpy(acpi_device_name(device), ACPI_VIDEO_BUS_NAME);
1758         strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
1759         device->driver_data = video;
1760
1761         acpi_video_bus_find_cap(video);
1762         error = acpi_video_bus_check(video);
1763         if (error)
1764                 goto err_free_video;
1765
1766         mutex_init(&video->device_list_lock);
1767         INIT_LIST_HEAD(&video->video_device_list);
1768
1769         error = acpi_video_bus_get_devices(video, device);
1770         if (error)
1771                 goto err_put_video;
1772
1773         video->input = input = input_allocate_device();
1774         if (!input) {
1775                 error = -ENOMEM;
1776                 goto err_put_video;
1777         }
1778
1779         error = acpi_video_bus_start_devices(video);
1780         if (error)
1781                 goto err_free_input_dev;
1782
1783         snprintf(video->phys, sizeof(video->phys),
1784                 "%s/video/input0", acpi_device_hid(video->device));
1785
1786         input->name = acpi_device_name(video->device);
1787         input->phys = video->phys;
1788         input->id.bustype = BUS_HOST;
1789         input->id.product = 0x06;
1790         input->dev.parent = &device->dev;
1791         input->evbit[0] = BIT(EV_KEY);
1792         set_bit(KEY_SWITCHVIDEOMODE, input->keybit);
1793         set_bit(KEY_VIDEO_NEXT, input->keybit);
1794         set_bit(KEY_VIDEO_PREV, input->keybit);
1795         set_bit(KEY_BRIGHTNESS_CYCLE, input->keybit);
1796         set_bit(KEY_BRIGHTNESSUP, input->keybit);
1797         set_bit(KEY_BRIGHTNESSDOWN, input->keybit);
1798         set_bit(KEY_BRIGHTNESS_ZERO, input->keybit);
1799         set_bit(KEY_DISPLAY_OFF, input->keybit);
1800
1801         printk(KERN_INFO PREFIX "%s [%s] (multi-head: %s  rom: %s  post: %s)\n",
1802                ACPI_VIDEO_DEVICE_NAME, acpi_device_bid(device),
1803                video->flags.multihead ? "yes" : "no",
1804                video->flags.rom ? "yes" : "no",
1805                video->flags.post ? "yes" : "no");
1806
1807         video->pm_nb.notifier_call = acpi_video_resume;
1808         video->pm_nb.priority = 0;
1809         error = register_pm_notifier(&video->pm_nb);
1810         if (error)
1811                 goto err_stop_video;
1812
1813         error = input_register_device(input);
1814         if (error)
1815                 goto err_unregister_pm_notifier;
1816
1817         return 0;
1818
1819  err_unregister_pm_notifier:
1820         unregister_pm_notifier(&video->pm_nb);
1821  err_stop_video:
1822         acpi_video_bus_stop_devices(video);
1823  err_free_input_dev:
1824         input_free_device(input);
1825  err_put_video:
1826         acpi_video_bus_put_devices(video);
1827         kfree(video->attached_array);
1828  err_free_video:
1829         kfree(video);
1830         device->driver_data = NULL;
1831
1832         return error;
1833 }
1834
1835 static int acpi_video_bus_remove(struct acpi_device *device)
1836 {
1837         struct acpi_video_bus *video = NULL;
1838
1839
1840         if (!device || !acpi_driver_data(device))
1841                 return -EINVAL;
1842
1843         video = acpi_driver_data(device);
1844
1845         unregister_pm_notifier(&video->pm_nb);
1846
1847         acpi_video_bus_stop_devices(video);
1848         acpi_video_bus_put_devices(video);
1849
1850         input_unregister_device(video->input);
1851         kfree(video->attached_array);
1852         kfree(video);
1853
1854         return 0;
1855 }
1856
1857 static int __init is_i740(struct pci_dev *dev)
1858 {
1859         if (dev->device == 0x00D1)
1860                 return 1;
1861         if (dev->device == 0x7000)
1862                 return 1;
1863         return 0;
1864 }
1865
1866 static int __init intel_opregion_present(void)
1867 {
1868         int opregion = 0;
1869         struct pci_dev *dev = NULL;
1870         u32 address;
1871
1872         for_each_pci_dev(dev) {
1873                 if ((dev->class >> 8) != PCI_CLASS_DISPLAY_VGA)
1874                         continue;
1875                 if (dev->vendor != PCI_VENDOR_ID_INTEL)
1876                         continue;
1877                 /* We don't want to poke around undefined i740 registers */
1878                 if (is_i740(dev))
1879                         continue;
1880                 pci_read_config_dword(dev, 0xfc, &address);
1881                 if (!address)
1882                         continue;
1883                 opregion = 1;
1884         }
1885         return opregion;
1886 }
1887
1888 int acpi_video_register(void)
1889 {
1890         int result = 0;
1891         if (register_count) {
1892                 /*
1893                  * if the function of acpi_video_register is already called,
1894                  * don't register the acpi_vide_bus again and return no error.
1895                  */
1896                 return 0;
1897         }
1898
1899         result = acpi_bus_register_driver(&acpi_video_bus);
1900         if (result < 0)
1901                 return -ENODEV;
1902
1903         /*
1904          * When the acpi_video_bus is loaded successfully, increase
1905          * the counter reference.
1906          */
1907         register_count = 1;
1908
1909         return 0;
1910 }
1911 EXPORT_SYMBOL(acpi_video_register);
1912
1913 void acpi_video_unregister(void)
1914 {
1915         if (!register_count) {
1916                 /*
1917                  * If the acpi video bus is already unloaded, don't
1918                  * unload it again and return directly.
1919                  */
1920                 return;
1921         }
1922         acpi_bus_unregister_driver(&acpi_video_bus);
1923
1924         register_count = 0;
1925
1926         return;
1927 }
1928 EXPORT_SYMBOL(acpi_video_unregister);
1929
1930 /*
1931  * This is kind of nasty. Hardware using Intel chipsets may require
1932  * the video opregion code to be run first in order to initialise
1933  * state before any ACPI video calls are made. To handle this we defer
1934  * registration of the video class until the opregion code has run.
1935  */
1936
1937 static int __init acpi_video_init(void)
1938 {
1939         dmi_check_system(video_dmi_table);
1940
1941         if (intel_opregion_present())
1942                 return 0;
1943
1944         return acpi_video_register();
1945 }
1946
1947 static void __exit acpi_video_exit(void)
1948 {
1949         acpi_video_unregister();
1950
1951         return;
1952 }
1953
1954 module_init(acpi_video_init);
1955 module_exit(acpi_video_exit);