Merge remote-tracking branch 'lsk/v3.10/topic/arm64-crypto' into linux-linaro-lsk
[firefly-linux-kernel-4.4.55.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 = "Fujitsu E753",
454          .matches = {
455                 DMI_MATCH(DMI_BOARD_VENDOR, "FUJITSU"),
456                 DMI_MATCH(DMI_PRODUCT_NAME, "LIFEBOOK E753"),
457                 },
458         },
459         {
460          .callback = video_ignore_initial_backlight,
461          .ident = "HP Pavilion dm4",
462          .matches = {
463                 DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
464                 DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion dm4 Notebook PC"),
465                 },
466         },
467         {
468          .callback = video_ignore_initial_backlight,
469          .ident = "HP Pavilion g6 Notebook PC",
470          .matches = {
471                  DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
472                  DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion g6 Notebook PC"),
473                 },
474         },
475         {
476          .callback = video_ignore_initial_backlight,
477          .ident = "HP 1000 Notebook PC",
478          .matches = {
479                 DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
480                 DMI_MATCH(DMI_PRODUCT_NAME, "HP 1000 Notebook PC"),
481                 },
482         },
483         {
484          .callback = video_ignore_initial_backlight,
485          .ident = "HP Pavilion m4",
486          .matches = {
487                 DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
488                 DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion m4 Notebook PC"),
489                 },
490         },
491         {}
492 };
493
494 static unsigned long long
495 acpi_video_bqc_value_to_level(struct acpi_video_device *device,
496                               unsigned long long bqc_value)
497 {
498         unsigned long long level;
499
500         if (device->brightness->flags._BQC_use_index) {
501                 /*
502                  * _BQC returns an index that doesn't account for
503                  * the first 2 items with special meaning, so we need
504                  * to compensate for that by offsetting ourselves
505                  */
506                 if (device->brightness->flags._BCL_reversed)
507                         bqc_value = device->brightness->count - 3 - bqc_value;
508
509                 level = device->brightness->levels[bqc_value + 2];
510         } else {
511                 level = bqc_value;
512         }
513
514         level += bqc_offset_aml_bug_workaround;
515
516         return level;
517 }
518
519 static int
520 acpi_video_device_lcd_get_level_current(struct acpi_video_device *device,
521                                         unsigned long long *level, bool raw)
522 {
523         acpi_status status = AE_OK;
524         int i;
525
526         if (device->cap._BQC || device->cap._BCQ) {
527                 char *buf = device->cap._BQC ? "_BQC" : "_BCQ";
528
529                 status = acpi_evaluate_integer(device->dev->handle, buf,
530                                                 NULL, level);
531                 if (ACPI_SUCCESS(status)) {
532                         if (raw) {
533                                 /*
534                                  * Caller has indicated he wants the raw
535                                  * value returned by _BQC, so don't furtherly
536                                  * mess with the value.
537                                  */
538                                 return 0;
539                         }
540
541                         *level = acpi_video_bqc_value_to_level(device, *level);
542
543                         for (i = 2; i < device->brightness->count; i++)
544                                 if (device->brightness->levels[i] == *level) {
545                                         device->brightness->curr = *level;
546                                         return 0;
547                         }
548                         /*
549                          * BQC returned an invalid level.
550                          * Stop using it.
551                          */
552                         ACPI_WARNING((AE_INFO,
553                                       "%s returned an invalid level",
554                                       buf));
555                         device->cap._BQC = device->cap._BCQ = 0;
556                 } else {
557                         /* Fixme:
558                          * should we return an error or ignore this failure?
559                          * dev->brightness->curr is a cached value which stores
560                          * the correct current backlight level in most cases.
561                          * ACPI video backlight still works w/ buggy _BQC.
562                          * http://bugzilla.kernel.org/show_bug.cgi?id=12233
563                          */
564                         ACPI_WARNING((AE_INFO, "Evaluating %s failed", buf));
565                         device->cap._BQC = device->cap._BCQ = 0;
566                 }
567         }
568
569         *level = device->brightness->curr;
570         return 0;
571 }
572
573 static int
574 acpi_video_device_EDID(struct acpi_video_device *device,
575                        union acpi_object **edid, ssize_t length)
576 {
577         int status;
578         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
579         union acpi_object *obj;
580         union acpi_object arg0 = { ACPI_TYPE_INTEGER };
581         struct acpi_object_list args = { 1, &arg0 };
582
583
584         *edid = NULL;
585
586         if (!device)
587                 return -ENODEV;
588         if (length == 128)
589                 arg0.integer.value = 1;
590         else if (length == 256)
591                 arg0.integer.value = 2;
592         else
593                 return -EINVAL;
594
595         status = acpi_evaluate_object(device->dev->handle, "_DDC", &args, &buffer);
596         if (ACPI_FAILURE(status))
597                 return -ENODEV;
598
599         obj = buffer.pointer;
600
601         if (obj && obj->type == ACPI_TYPE_BUFFER)
602                 *edid = obj;
603         else {
604                 printk(KERN_ERR PREFIX "Invalid _DDC data\n");
605                 status = -EFAULT;
606                 kfree(obj);
607         }
608
609         return status;
610 }
611
612 /* bus */
613
614 /*
615  *  Arg:
616  *      video           : video bus device pointer
617  *      bios_flag       : 
618  *              0.      The system BIOS should NOT automatically switch(toggle)
619  *                      the active display output.
620  *              1.      The system BIOS should automatically switch (toggle) the
621  *                      active display output. No switch event.
622  *              2.      The _DGS value should be locked.
623  *              3.      The system BIOS should not automatically switch (toggle) the
624  *                      active display output, but instead generate the display switch
625  *                      event notify code.
626  *      lcd_flag        :
627  *              0.      The system BIOS should automatically control the brightness level
628  *                      of the LCD when the power changes from AC to DC
629  *              1.      The system BIOS should NOT automatically control the brightness 
630  *                      level of the LCD when the power changes from AC to DC.
631  * Return Value:
632  *              -EINVAL wrong arg.
633  */
634
635 static int
636 acpi_video_bus_DOS(struct acpi_video_bus *video, int bios_flag, int lcd_flag)
637 {
638         acpi_status status;
639         union acpi_object arg0 = { ACPI_TYPE_INTEGER };
640         struct acpi_object_list args = { 1, &arg0 };
641
642         if (!video->cap._DOS)
643                 return 0;
644
645         if (bios_flag < 0 || bios_flag > 3 || lcd_flag < 0 || lcd_flag > 1)
646                 return -EINVAL;
647         arg0.integer.value = (lcd_flag << 2) | bios_flag;
648         video->dos_setting = arg0.integer.value;
649         status = acpi_evaluate_object(video->device->handle, "_DOS",
650                 &args, NULL);
651         if (ACPI_FAILURE(status))
652                 return -EIO;
653
654         return 0;
655 }
656
657 /*
658  * Simple comparison function used to sort backlight levels.
659  */
660
661 static int
662 acpi_video_cmp_level(const void *a, const void *b)
663 {
664         return *(int *)a - *(int *)b;
665 }
666
667 /*
668  * Decides if _BQC/_BCQ for this system is usable
669  *
670  * We do this by changing the level first and then read out the current
671  * brightness level, if the value does not match, find out if it is using
672  * index. If not, clear the _BQC/_BCQ capability.
673  */
674 static int acpi_video_bqc_quirk(struct acpi_video_device *device,
675                                 int max_level, int current_level)
676 {
677         struct acpi_video_device_brightness *br = device->brightness;
678         int result;
679         unsigned long long level;
680         int test_level;
681
682         /* don't mess with existing known broken systems */
683         if (bqc_offset_aml_bug_workaround)
684                 return 0;
685
686         /*
687          * Some systems always report current brightness level as maximum
688          * through _BQC, we need to test another value for them.
689          */
690         test_level = current_level == max_level ? br->levels[2] : max_level;
691
692         result = acpi_video_device_lcd_set_level(device, test_level);
693         if (result)
694                 return result;
695
696         result = acpi_video_device_lcd_get_level_current(device, &level, true);
697         if (result)
698                 return result;
699
700         if (level != test_level) {
701                 /* buggy _BQC found, need to find out if it uses index */
702                 if (level < br->count) {
703                         if (br->flags._BCL_reversed)
704                                 level = br->count - 3 - level;
705                         if (br->levels[level + 2] == test_level)
706                                 br->flags._BQC_use_index = 1;
707                 }
708
709                 if (!br->flags._BQC_use_index)
710                         device->cap._BQC = device->cap._BCQ = 0;
711         }
712
713         return 0;
714 }
715
716
717 /*
718  *  Arg:        
719  *      device  : video output device (LCD, CRT, ..)
720  *
721  *  Return Value:
722  *      Maximum brightness level
723  *
724  *  Allocate and initialize device->brightness.
725  */
726
727 static int
728 acpi_video_init_brightness(struct acpi_video_device *device)
729 {
730         union acpi_object *obj = NULL;
731         int i, max_level = 0, count = 0, level_ac_battery = 0;
732         unsigned long long level, level_old;
733         union acpi_object *o;
734         struct acpi_video_device_brightness *br = NULL;
735         int result = -EINVAL;
736         u32 value;
737
738         if (!ACPI_SUCCESS(acpi_video_device_lcd_query_levels(device, &obj))) {
739                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Could not query available "
740                                                 "LCD brightness level\n"));
741                 goto out;
742         }
743
744         if (obj->package.count < 2)
745                 goto out;
746
747         br = kzalloc(sizeof(*br), GFP_KERNEL);
748         if (!br) {
749                 printk(KERN_ERR "can't allocate memory\n");
750                 result = -ENOMEM;
751                 goto out;
752         }
753
754         br->levels = kmalloc((obj->package.count + 2) * sizeof *(br->levels),
755                                 GFP_KERNEL);
756         if (!br->levels) {
757                 result = -ENOMEM;
758                 goto out_free;
759         }
760
761         for (i = 0; i < obj->package.count; i++) {
762                 o = (union acpi_object *)&obj->package.elements[i];
763                 if (o->type != ACPI_TYPE_INTEGER) {
764                         printk(KERN_ERR PREFIX "Invalid data\n");
765                         continue;
766                 }
767                 value = (u32) o->integer.value;
768                 /* Skip duplicate entries */
769                 if (count > 2 && br->levels[count - 1] == value)
770                         continue;
771
772                 br->levels[count] = value;
773
774                 if (br->levels[count] > max_level)
775                         max_level = br->levels[count];
776                 count++;
777         }
778
779         /*
780          * some buggy BIOS don't export the levels
781          * when machine is on AC/Battery in _BCL package.
782          * In this case, the first two elements in _BCL packages
783          * are also supported brightness levels that OS should take care of.
784          */
785         for (i = 2; i < count; i++) {
786                 if (br->levels[i] == br->levels[0])
787                         level_ac_battery++;
788                 if (br->levels[i] == br->levels[1])
789                         level_ac_battery++;
790         }
791
792         if (level_ac_battery < 2) {
793                 level_ac_battery = 2 - level_ac_battery;
794                 br->flags._BCL_no_ac_battery_levels = 1;
795                 for (i = (count - 1 + level_ac_battery); i >= 2; i--)
796                         br->levels[i] = br->levels[i - level_ac_battery];
797                 count += level_ac_battery;
798         } else if (level_ac_battery > 2)
799                 ACPI_ERROR((AE_INFO, "Too many duplicates in _BCL package"));
800
801         /* Check if the _BCL package is in a reversed order */
802         if (max_level == br->levels[2]) {
803                 br->flags._BCL_reversed = 1;
804                 sort(&br->levels[2], count - 2, sizeof(br->levels[2]),
805                         acpi_video_cmp_level, NULL);
806         } else if (max_level != br->levels[count - 1])
807                 ACPI_ERROR((AE_INFO,
808                             "Found unordered _BCL package"));
809
810         br->count = count;
811         device->brightness = br;
812
813         /* Check the input/output of _BQC/_BCL/_BCM */
814         if ((max_level < 100) && (max_level <= (count - 2)))
815                 br->flags._BCL_use_index = 1;
816
817         /*
818          * _BCM is always consistent with _BCL,
819          * at least for all the laptops we have ever seen.
820          */
821         br->flags._BCM_use_index = br->flags._BCL_use_index;
822
823         /* _BQC uses INDEX while _BCL uses VALUE in some laptops */
824         br->curr = level = max_level;
825
826         if (!device->cap._BQC)
827                 goto set_level;
828
829         result = acpi_video_device_lcd_get_level_current(device,
830                                                          &level_old, true);
831         if (result)
832                 goto out_free_levels;
833
834         result = acpi_video_bqc_quirk(device, max_level, level_old);
835         if (result)
836                 goto out_free_levels;
837         /*
838          * cap._BQC may get cleared due to _BQC is found to be broken
839          * in acpi_video_bqc_quirk, so check again here.
840          */
841         if (!device->cap._BQC)
842                 goto set_level;
843
844         if (use_bios_initial_backlight) {
845                 level = acpi_video_bqc_value_to_level(device, level_old);
846                 /*
847                  * On some buggy laptops, _BQC returns an uninitialized
848                  * value when invoked for the first time, i.e.
849                  * level_old is invalid (no matter whether it's a level
850                  * or an index). Set the backlight to max_level in this case.
851                  */
852                 for (i = 2; i < br->count; i++)
853                         if (level_old == br->levels[i])
854                                 break;
855                 if (i == br->count || !level)
856                         level = max_level;
857         }
858
859 set_level:
860         result = acpi_video_device_lcd_set_level(device, level);
861         if (result)
862                 goto out_free_levels;
863
864         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
865                           "found %d brightness levels\n", count - 2));
866         kfree(obj);
867         return result;
868
869 out_free_levels:
870         kfree(br->levels);
871 out_free:
872         kfree(br);
873 out:
874         device->brightness = NULL;
875         kfree(obj);
876         return result;
877 }
878
879 /*
880  *  Arg:
881  *      device  : video output device (LCD, CRT, ..)
882  *
883  *  Return Value:
884  *      None
885  *
886  *  Find out all required AML methods defined under the output
887  *  device.
888  */
889
890 static void acpi_video_device_find_cap(struct acpi_video_device *device)
891 {
892         acpi_handle h_dummy1;
893
894         if (ACPI_SUCCESS(acpi_get_handle(device->dev->handle, "_ADR", &h_dummy1))) {
895                 device->cap._ADR = 1;
896         }
897         if (ACPI_SUCCESS(acpi_get_handle(device->dev->handle, "_BCL", &h_dummy1))) {
898                 device->cap._BCL = 1;
899         }
900         if (ACPI_SUCCESS(acpi_get_handle(device->dev->handle, "_BCM", &h_dummy1))) {
901                 device->cap._BCM = 1;
902         }
903         if (ACPI_SUCCESS(acpi_get_handle(device->dev->handle,"_BQC",&h_dummy1)))
904                 device->cap._BQC = 1;
905         else if (ACPI_SUCCESS(acpi_get_handle(device->dev->handle, "_BCQ",
906                                 &h_dummy1))) {
907                 printk(KERN_WARNING FW_BUG "_BCQ is used instead of _BQC\n");
908                 device->cap._BCQ = 1;
909         }
910
911         if (ACPI_SUCCESS(acpi_get_handle(device->dev->handle, "_DDC", &h_dummy1))) {
912                 device->cap._DDC = 1;
913         }
914
915         if (acpi_video_backlight_support()) {
916                 struct backlight_properties props;
917                 struct pci_dev *pdev;
918                 acpi_handle acpi_parent;
919                 struct device *parent = NULL;
920                 int result;
921                 static int count = 0;
922                 char *name;
923
924                 result = acpi_video_init_brightness(device);
925                 if (result)
926                         return;
927                 name = kasprintf(GFP_KERNEL, "acpi_video%d", count);
928                 if (!name)
929                         return;
930                 count++;
931
932                 acpi_get_parent(device->dev->handle, &acpi_parent);
933
934                 pdev = acpi_get_pci_dev(acpi_parent);
935                 if (pdev) {
936                         parent = &pdev->dev;
937                         pci_dev_put(pdev);
938                 }
939
940                 memset(&props, 0, sizeof(struct backlight_properties));
941                 props.type = BACKLIGHT_FIRMWARE;
942                 props.max_brightness = device->brightness->count - 3;
943                 device->backlight = backlight_device_register(name,
944                                                               parent,
945                                                               device,
946                                                               &acpi_backlight_ops,
947                                                               &props);
948                 kfree(name);
949                 if (IS_ERR(device->backlight))
950                         return;
951
952                 /*
953                  * Save current brightness level in case we have to restore it
954                  * before acpi_video_device_lcd_set_level() is called next time.
955                  */
956                 device->backlight->props.brightness =
957                                 acpi_video_get_brightness(device->backlight);
958
959                 device->cooling_dev = thermal_cooling_device_register("LCD",
960                                         device->dev, &video_cooling_ops);
961                 if (IS_ERR(device->cooling_dev)) {
962                         /*
963                          * Set cooling_dev to NULL so we don't crash trying to
964                          * free it.
965                          * Also, why the hell we are returning early and
966                          * not attempt to register video output if cooling
967                          * device registration failed?
968                          * -- dtor
969                          */
970                         device->cooling_dev = NULL;
971                         return;
972                 }
973
974                 dev_info(&device->dev->dev, "registered as cooling_device%d\n",
975                          device->cooling_dev->id);
976                 result = sysfs_create_link(&device->dev->dev.kobj,
977                                 &device->cooling_dev->device.kobj,
978                                 "thermal_cooling");
979                 if (result)
980                         printk(KERN_ERR PREFIX "Create sysfs link\n");
981                 result = sysfs_create_link(&device->cooling_dev->device.kobj,
982                                 &device->dev->dev.kobj, "device");
983                 if (result)
984                         printk(KERN_ERR PREFIX "Create sysfs link\n");
985
986         }
987 }
988
989 /*
990  *  Arg:        
991  *      device  : video output device (VGA)
992  *
993  *  Return Value:
994  *      None
995  *
996  *  Find out all required AML methods defined under the video bus device.
997  */
998
999 static void acpi_video_bus_find_cap(struct acpi_video_bus *video)
1000 {
1001         acpi_handle h_dummy1;
1002
1003         if (ACPI_SUCCESS(acpi_get_handle(video->device->handle, "_DOS", &h_dummy1))) {
1004                 video->cap._DOS = 1;
1005         }
1006         if (ACPI_SUCCESS(acpi_get_handle(video->device->handle, "_DOD", &h_dummy1))) {
1007                 video->cap._DOD = 1;
1008         }
1009         if (ACPI_SUCCESS(acpi_get_handle(video->device->handle, "_ROM", &h_dummy1))) {
1010                 video->cap._ROM = 1;
1011         }
1012         if (ACPI_SUCCESS(acpi_get_handle(video->device->handle, "_GPD", &h_dummy1))) {
1013                 video->cap._GPD = 1;
1014         }
1015         if (ACPI_SUCCESS(acpi_get_handle(video->device->handle, "_SPD", &h_dummy1))) {
1016                 video->cap._SPD = 1;
1017         }
1018         if (ACPI_SUCCESS(acpi_get_handle(video->device->handle, "_VPO", &h_dummy1))) {
1019                 video->cap._VPO = 1;
1020         }
1021 }
1022
1023 /*
1024  * Check whether the video bus device has required AML method to
1025  * support the desired features
1026  */
1027
1028 static int acpi_video_bus_check(struct acpi_video_bus *video)
1029 {
1030         acpi_status status = -ENOENT;
1031         struct pci_dev *dev;
1032
1033         if (!video)
1034                 return -EINVAL;
1035
1036         dev = acpi_get_pci_dev(video->device->handle);
1037         if (!dev)
1038                 return -ENODEV;
1039         pci_dev_put(dev);
1040
1041         /* Since there is no HID, CID and so on for VGA driver, we have
1042          * to check well known required nodes.
1043          */
1044
1045         /* Does this device support video switching? */
1046         if (video->cap._DOS || video->cap._DOD) {
1047                 if (!video->cap._DOS) {
1048                         printk(KERN_WARNING FW_BUG
1049                                 "ACPI(%s) defines _DOD but not _DOS\n",
1050                                 acpi_device_bid(video->device));
1051                 }
1052                 video->flags.multihead = 1;
1053                 status = 0;
1054         }
1055
1056         /* Does this device support retrieving a video ROM? */
1057         if (video->cap._ROM) {
1058                 video->flags.rom = 1;
1059                 status = 0;
1060         }
1061
1062         /* Does this device support configuring which video device to POST? */
1063         if (video->cap._GPD && video->cap._SPD && video->cap._VPO) {
1064                 video->flags.post = 1;
1065                 status = 0;
1066         }
1067
1068         return status;
1069 }
1070
1071 /* --------------------------------------------------------------------------
1072                                  Driver Interface
1073    -------------------------------------------------------------------------- */
1074
1075 /* device interface */
1076 static struct acpi_video_device_attrib*
1077 acpi_video_get_device_attr(struct acpi_video_bus *video, unsigned long device_id)
1078 {
1079         struct acpi_video_enumerated_device *ids;
1080         int i;
1081
1082         for (i = 0; i < video->attached_count; i++) {
1083                 ids = &video->attached_array[i];
1084                 if ((ids->value.int_val & 0xffff) == device_id)
1085                         return &ids->value.attrib;
1086         }
1087
1088         return NULL;
1089 }
1090
1091 static int
1092 acpi_video_get_device_type(struct acpi_video_bus *video,
1093                            unsigned long device_id)
1094 {
1095         struct acpi_video_enumerated_device *ids;
1096         int i;
1097
1098         for (i = 0; i < video->attached_count; i++) {
1099                 ids = &video->attached_array[i];
1100                 if ((ids->value.int_val & 0xffff) == device_id)
1101                         return ids->value.int_val;
1102         }
1103
1104         return 0;
1105 }
1106
1107 static int
1108 acpi_video_bus_get_one_device(struct acpi_device *device,
1109                               struct acpi_video_bus *video)
1110 {
1111         unsigned long long device_id;
1112         int status, device_type;
1113         struct acpi_video_device *data;
1114         struct acpi_video_device_attrib* attribute;
1115
1116         status =
1117             acpi_evaluate_integer(device->handle, "_ADR", NULL, &device_id);
1118         /* Some device omits _ADR, we skip them instead of fail */
1119         if (ACPI_FAILURE(status))
1120                 return 0;
1121
1122         data = kzalloc(sizeof(struct acpi_video_device), GFP_KERNEL);
1123         if (!data)
1124                 return -ENOMEM;
1125
1126         strcpy(acpi_device_name(device), ACPI_VIDEO_DEVICE_NAME);
1127         strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
1128         device->driver_data = data;
1129
1130         data->device_id = device_id;
1131         data->video = video;
1132         data->dev = device;
1133
1134         attribute = acpi_video_get_device_attr(video, device_id);
1135
1136         if((attribute != NULL) && attribute->device_id_scheme) {
1137                 switch (attribute->display_type) {
1138                 case ACPI_VIDEO_DISPLAY_CRT:
1139                         data->flags.crt = 1;
1140                         break;
1141                 case ACPI_VIDEO_DISPLAY_TV:
1142                         data->flags.tvout = 1;
1143                         break;
1144                 case ACPI_VIDEO_DISPLAY_DVI:
1145                         data->flags.dvi = 1;
1146                         break;
1147                 case ACPI_VIDEO_DISPLAY_LCD:
1148                         data->flags.lcd = 1;
1149                         break;
1150                 default:
1151                         data->flags.unknown = 1;
1152                         break;
1153                 }
1154                 if(attribute->bios_can_detect)
1155                         data->flags.bios = 1;
1156         } else {
1157                 /* Check for legacy IDs */
1158                 device_type = acpi_video_get_device_type(video, device_id);
1159                 /* Ignore bits 16 and 18-20 */
1160                 switch (device_type & 0xffe2ffff) {
1161                         case ACPI_VIDEO_DISPLAY_LEGACY_MONITOR:
1162                                 data->flags.crt = 1;
1163                                 break;
1164                         case ACPI_VIDEO_DISPLAY_LEGACY_PANEL:
1165                                 data->flags.lcd = 1;
1166                                 break;
1167                         case ACPI_VIDEO_DISPLAY_LEGACY_TV:
1168                                 data->flags.tvout = 1;
1169                                 break;
1170                         default:
1171                                 data->flags.unknown = 1;
1172                 }
1173         }
1174
1175         acpi_video_device_bind(video, data);
1176         acpi_video_device_find_cap(data);
1177
1178         status = acpi_install_notify_handler(device->handle, ACPI_DEVICE_NOTIFY,
1179                                              acpi_video_device_notify, data);
1180         if (ACPI_FAILURE(status))
1181                 dev_err(&device->dev, "Error installing notify handler\n");
1182         else
1183                 data->flags.notify = 1;
1184
1185         mutex_lock(&video->device_list_lock);
1186         list_add_tail(&data->entry, &video->video_device_list);
1187         mutex_unlock(&video->device_list_lock);
1188
1189         return status;
1190 }
1191
1192 /*
1193  *  Arg:
1194  *      video   : video bus device 
1195  *
1196  *  Return:
1197  *      none
1198  *  
1199  *  Enumerate the video device list of the video bus, 
1200  *  bind the ids with the corresponding video devices
1201  *  under the video bus.
1202  */
1203
1204 static void acpi_video_device_rebind(struct acpi_video_bus *video)
1205 {
1206         struct acpi_video_device *dev;
1207
1208         mutex_lock(&video->device_list_lock);
1209
1210         list_for_each_entry(dev, &video->video_device_list, entry)
1211                 acpi_video_device_bind(video, dev);
1212
1213         mutex_unlock(&video->device_list_lock);
1214 }
1215
1216 /*
1217  *  Arg:
1218  *      video   : video bus device 
1219  *      device  : video output device under the video 
1220  *              bus
1221  *
1222  *  Return:
1223  *      none
1224  *  
1225  *  Bind the ids with the corresponding video devices
1226  *  under the video bus.
1227  */
1228
1229 static void
1230 acpi_video_device_bind(struct acpi_video_bus *video,
1231                        struct acpi_video_device *device)
1232 {
1233         struct acpi_video_enumerated_device *ids;
1234         int i;
1235
1236         for (i = 0; i < video->attached_count; i++) {
1237                 ids = &video->attached_array[i];
1238                 if (device->device_id == (ids->value.int_val & 0xffff)) {
1239                         ids->bind_info = device;
1240                         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "device_bind %d\n", i));
1241                 }
1242         }
1243 }
1244
1245 /*
1246  *  Arg:
1247  *      video   : video bus device 
1248  *
1249  *  Return:
1250  *      < 0     : error
1251  *  
1252  *  Call _DOD to enumerate all devices attached to display adapter
1253  *
1254  */
1255
1256 static int acpi_video_device_enumerate(struct acpi_video_bus *video)
1257 {
1258         int status;
1259         int count;
1260         int i;
1261         struct acpi_video_enumerated_device *active_list;
1262         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1263         union acpi_object *dod = NULL;
1264         union acpi_object *obj;
1265
1266         status = acpi_evaluate_object(video->device->handle, "_DOD", NULL, &buffer);
1267         if (!ACPI_SUCCESS(status)) {
1268                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _DOD"));
1269                 return status;
1270         }
1271
1272         dod = buffer.pointer;
1273         if (!dod || (dod->type != ACPI_TYPE_PACKAGE)) {
1274                 ACPI_EXCEPTION((AE_INFO, status, "Invalid _DOD data"));
1275                 status = -EFAULT;
1276                 goto out;
1277         }
1278
1279         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d video heads in _DOD\n",
1280                           dod->package.count));
1281
1282         active_list = kcalloc(1 + dod->package.count,
1283                               sizeof(struct acpi_video_enumerated_device),
1284                               GFP_KERNEL);
1285         if (!active_list) {
1286                 status = -ENOMEM;
1287                 goto out;
1288         }
1289
1290         count = 0;
1291         for (i = 0; i < dod->package.count; i++) {
1292                 obj = &dod->package.elements[i];
1293
1294                 if (obj->type != ACPI_TYPE_INTEGER) {
1295                         printk(KERN_ERR PREFIX
1296                                 "Invalid _DOD data in element %d\n", i);
1297                         continue;
1298                 }
1299
1300                 active_list[count].value.int_val = obj->integer.value;
1301                 active_list[count].bind_info = NULL;
1302                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "dod element[%d] = %d\n", i,
1303                                   (int)obj->integer.value));
1304                 count++;
1305         }
1306
1307         kfree(video->attached_array);
1308
1309         video->attached_array = active_list;
1310         video->attached_count = count;
1311
1312  out:
1313         kfree(buffer.pointer);
1314         return status;
1315 }
1316
1317 static int
1318 acpi_video_get_next_level(struct acpi_video_device *device,
1319                           u32 level_current, u32 event)
1320 {
1321         int min, max, min_above, max_below, i, l, delta = 255;
1322         max = max_below = 0;
1323         min = min_above = 255;
1324         /* Find closest level to level_current */
1325         for (i = 2; i < device->brightness->count; i++) {
1326                 l = device->brightness->levels[i];
1327                 if (abs(l - level_current) < abs(delta)) {
1328                         delta = l - level_current;
1329                         if (!delta)
1330                                 break;
1331                 }
1332         }
1333         /* Ajust level_current to closest available level */
1334         level_current += delta;
1335         for (i = 2; i < device->brightness->count; i++) {
1336                 l = device->brightness->levels[i];
1337                 if (l < min)
1338                         min = l;
1339                 if (l > max)
1340                         max = l;
1341                 if (l < min_above && l > level_current)
1342                         min_above = l;
1343                 if (l > max_below && l < level_current)
1344                         max_below = l;
1345         }
1346
1347         switch (event) {
1348         case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:
1349                 return (level_current < max) ? min_above : min;
1350         case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:
1351                 return (level_current < max) ? min_above : max;
1352         case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:
1353                 return (level_current > min) ? max_below : min;
1354         case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS:
1355         case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:
1356                 return 0;
1357         default:
1358                 return level_current;
1359         }
1360 }
1361
1362 static int
1363 acpi_video_switch_brightness(struct acpi_video_device *device, int event)
1364 {
1365         unsigned long long level_current, level_next;
1366         int result = -EINVAL;
1367
1368         /* no warning message if acpi_backlight=vendor is used */
1369         if (!acpi_video_backlight_support())
1370                 return 0;
1371
1372         if (!device->brightness)
1373                 goto out;
1374
1375         result = acpi_video_device_lcd_get_level_current(device,
1376                                                          &level_current,
1377                                                          false);
1378         if (result)
1379                 goto out;
1380
1381         level_next = acpi_video_get_next_level(device, level_current, event);
1382
1383         result = acpi_video_device_lcd_set_level(device, level_next);
1384
1385         if (!result)
1386                 backlight_force_update(device->backlight,
1387                                        BACKLIGHT_UPDATE_HOTKEY);
1388
1389 out:
1390         if (result)
1391                 printk(KERN_ERR PREFIX "Failed to switch the brightness\n");
1392
1393         return result;
1394 }
1395
1396 int acpi_video_get_edid(struct acpi_device *device, int type, int device_id,
1397                         void **edid)
1398 {
1399         struct acpi_video_bus *video;
1400         struct acpi_video_device *video_device;
1401         union acpi_object *buffer = NULL;
1402         acpi_status status;
1403         int i, length;
1404
1405         if (!device || !acpi_driver_data(device))
1406                 return -EINVAL;
1407
1408         video = acpi_driver_data(device);
1409
1410         for (i = 0; i < video->attached_count; i++) {
1411                 video_device = video->attached_array[i].bind_info;
1412                 length = 256;
1413
1414                 if (!video_device)
1415                         continue;
1416
1417                 if (!video_device->cap._DDC)
1418                         continue;
1419
1420                 if (type) {
1421                         switch (type) {
1422                         case ACPI_VIDEO_DISPLAY_CRT:
1423                                 if (!video_device->flags.crt)
1424                                         continue;
1425                                 break;
1426                         case ACPI_VIDEO_DISPLAY_TV:
1427                                 if (!video_device->flags.tvout)
1428                                         continue;
1429                                 break;
1430                         case ACPI_VIDEO_DISPLAY_DVI:
1431                                 if (!video_device->flags.dvi)
1432                                         continue;
1433                                 break;
1434                         case ACPI_VIDEO_DISPLAY_LCD:
1435                                 if (!video_device->flags.lcd)
1436                                         continue;
1437                                 break;
1438                         }
1439                 } else if (video_device->device_id != device_id) {
1440                         continue;
1441                 }
1442
1443                 status = acpi_video_device_EDID(video_device, &buffer, length);
1444
1445                 if (ACPI_FAILURE(status) || !buffer ||
1446                     buffer->type != ACPI_TYPE_BUFFER) {
1447                         length = 128;
1448                         status = acpi_video_device_EDID(video_device, &buffer,
1449                                                         length);
1450                         if (ACPI_FAILURE(status) || !buffer ||
1451                             buffer->type != ACPI_TYPE_BUFFER) {
1452                                 continue;
1453                         }
1454                 }
1455
1456                 *edid = buffer->buffer.pointer;
1457                 return length;
1458         }
1459
1460         return -ENODEV;
1461 }
1462 EXPORT_SYMBOL(acpi_video_get_edid);
1463
1464 static int
1465 acpi_video_bus_get_devices(struct acpi_video_bus *video,
1466                            struct acpi_device *device)
1467 {
1468         int status = 0;
1469         struct acpi_device *dev;
1470
1471         /*
1472          * There are systems where video module known to work fine regardless
1473          * of broken _DOD and ignoring returned value here doesn't cause
1474          * any issues later.
1475          */
1476         acpi_video_device_enumerate(video);
1477
1478         list_for_each_entry(dev, &device->children, node) {
1479
1480                 status = acpi_video_bus_get_one_device(dev, video);
1481                 if (status) {
1482                         dev_err(&dev->dev, "Can't attach device\n");
1483                         break;
1484                 }
1485         }
1486         return status;
1487 }
1488
1489 static int acpi_video_bus_put_one_device(struct acpi_video_device *device)
1490 {
1491         acpi_status status;
1492
1493         if (!device || !device->video)
1494                 return -ENOENT;
1495
1496         if (device->flags.notify) {
1497                 status = acpi_remove_notify_handler(device->dev->handle,
1498                                 ACPI_DEVICE_NOTIFY, acpi_video_device_notify);
1499                 if (ACPI_FAILURE(status))
1500                         dev_err(&device->dev->dev,
1501                                         "Can't remove video notify handler\n");
1502         }
1503
1504         if (device->backlight) {
1505                 backlight_device_unregister(device->backlight);
1506                 device->backlight = NULL;
1507         }
1508         if (device->cooling_dev) {
1509                 sysfs_remove_link(&device->dev->dev.kobj,
1510                                   "thermal_cooling");
1511                 sysfs_remove_link(&device->cooling_dev->device.kobj,
1512                                   "device");
1513                 thermal_cooling_device_unregister(device->cooling_dev);
1514                 device->cooling_dev = NULL;
1515         }
1516
1517         return 0;
1518 }
1519
1520 static int acpi_video_bus_put_devices(struct acpi_video_bus *video)
1521 {
1522         int status;
1523         struct acpi_video_device *dev, *next;
1524
1525         mutex_lock(&video->device_list_lock);
1526
1527         list_for_each_entry_safe(dev, next, &video->video_device_list, entry) {
1528
1529                 status = acpi_video_bus_put_one_device(dev);
1530                 if (ACPI_FAILURE(status))
1531                         printk(KERN_WARNING PREFIX
1532                                "hhuuhhuu bug in acpi video driver.\n");
1533
1534                 if (dev->brightness) {
1535                         kfree(dev->brightness->levels);
1536                         kfree(dev->brightness);
1537                 }
1538                 list_del(&dev->entry);
1539                 kfree(dev);
1540         }
1541
1542         mutex_unlock(&video->device_list_lock);
1543
1544         return 0;
1545 }
1546
1547 /* acpi_video interface */
1548
1549 static int acpi_video_bus_start_devices(struct acpi_video_bus *video)
1550 {
1551         return acpi_video_bus_DOS(video, 0, 0);
1552 }
1553
1554 static int acpi_video_bus_stop_devices(struct acpi_video_bus *video)
1555 {
1556         return acpi_video_bus_DOS(video, 0, 1);
1557 }
1558
1559 static void acpi_video_bus_notify(struct acpi_device *device, u32 event)
1560 {
1561         struct acpi_video_bus *video = acpi_driver_data(device);
1562         struct input_dev *input;
1563         int keycode = 0;
1564
1565         if (!video)
1566                 return;
1567
1568         input = video->input;
1569
1570         switch (event) {
1571         case ACPI_VIDEO_NOTIFY_SWITCH:  /* User requested a switch,
1572                                          * most likely via hotkey. */
1573                 acpi_bus_generate_proc_event(device, event, 0);
1574                 keycode = KEY_SWITCHVIDEOMODE;
1575                 break;
1576
1577         case ACPI_VIDEO_NOTIFY_PROBE:   /* User plugged in or removed a video
1578                                          * connector. */
1579                 acpi_video_device_enumerate(video);
1580                 acpi_video_device_rebind(video);
1581                 acpi_bus_generate_proc_event(device, event, 0);
1582                 keycode = KEY_SWITCHVIDEOMODE;
1583                 break;
1584
1585         case ACPI_VIDEO_NOTIFY_CYCLE:   /* Cycle Display output hotkey pressed. */
1586                 acpi_bus_generate_proc_event(device, event, 0);
1587                 keycode = KEY_SWITCHVIDEOMODE;
1588                 break;
1589         case ACPI_VIDEO_NOTIFY_NEXT_OUTPUT:     /* Next Display output hotkey pressed. */
1590                 acpi_bus_generate_proc_event(device, event, 0);
1591                 keycode = KEY_VIDEO_NEXT;
1592                 break;
1593         case ACPI_VIDEO_NOTIFY_PREV_OUTPUT:     /* previous Display output hotkey pressed. */
1594                 acpi_bus_generate_proc_event(device, event, 0);
1595                 keycode = KEY_VIDEO_PREV;
1596                 break;
1597
1598         default:
1599                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1600                                   "Unsupported event [0x%x]\n", event));
1601                 break;
1602         }
1603
1604         if (acpi_notifier_call_chain(device, event, 0))
1605                 /* Something vetoed the keypress. */
1606                 keycode = 0;
1607
1608         if (keycode) {
1609                 input_report_key(input, keycode, 1);
1610                 input_sync(input);
1611                 input_report_key(input, keycode, 0);
1612                 input_sync(input);
1613         }
1614
1615         return;
1616 }
1617
1618 static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data)
1619 {
1620         struct acpi_video_device *video_device = data;
1621         struct acpi_device *device = NULL;
1622         struct acpi_video_bus *bus;
1623         struct input_dev *input;
1624         int keycode = 0;
1625
1626         if (!video_device)
1627                 return;
1628
1629         device = video_device->dev;
1630         bus = video_device->video;
1631         input = bus->input;
1632
1633         switch (event) {
1634         case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:        /* Cycle brightness */
1635                 if (brightness_switch_enabled)
1636                         acpi_video_switch_brightness(video_device, event);
1637                 acpi_bus_generate_proc_event(device, event, 0);
1638                 keycode = KEY_BRIGHTNESS_CYCLE;
1639                 break;
1640         case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:  /* Increase brightness */
1641                 if (brightness_switch_enabled)
1642                         acpi_video_switch_brightness(video_device, event);
1643                 acpi_bus_generate_proc_event(device, event, 0);
1644                 keycode = KEY_BRIGHTNESSUP;
1645                 break;
1646         case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:  /* Decrease brightness */
1647                 if (brightness_switch_enabled)
1648                         acpi_video_switch_brightness(video_device, event);
1649                 acpi_bus_generate_proc_event(device, event, 0);
1650                 keycode = KEY_BRIGHTNESSDOWN;
1651                 break;
1652         case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS: /* zero brightness */
1653                 if (brightness_switch_enabled)
1654                         acpi_video_switch_brightness(video_device, event);
1655                 acpi_bus_generate_proc_event(device, event, 0);
1656                 keycode = KEY_BRIGHTNESS_ZERO;
1657                 break;
1658         case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:     /* display device off */
1659                 if (brightness_switch_enabled)
1660                         acpi_video_switch_brightness(video_device, event);
1661                 acpi_bus_generate_proc_event(device, event, 0);
1662                 keycode = KEY_DISPLAY_OFF;
1663                 break;
1664         default:
1665                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1666                                   "Unsupported event [0x%x]\n", event));
1667                 break;
1668         }
1669
1670         acpi_notifier_call_chain(device, event, 0);
1671
1672         if (keycode) {
1673                 input_report_key(input, keycode, 1);
1674                 input_sync(input);
1675                 input_report_key(input, keycode, 0);
1676                 input_sync(input);
1677         }
1678
1679         return;
1680 }
1681
1682 static int acpi_video_resume(struct notifier_block *nb,
1683                                 unsigned long val, void *ign)
1684 {
1685         struct acpi_video_bus *video;
1686         struct acpi_video_device *video_device;
1687         int i;
1688
1689         switch (val) {
1690         case PM_HIBERNATION_PREPARE:
1691         case PM_SUSPEND_PREPARE:
1692         case PM_RESTORE_PREPARE:
1693                 return NOTIFY_DONE;
1694         }
1695
1696         video = container_of(nb, struct acpi_video_bus, pm_nb);
1697
1698         dev_info(&video->device->dev, "Restoring backlight state\n");
1699
1700         for (i = 0; i < video->attached_count; i++) {
1701                 video_device = video->attached_array[i].bind_info;
1702                 if (video_device && video_device->backlight)
1703                         acpi_video_set_brightness(video_device->backlight);
1704         }
1705
1706         return NOTIFY_OK;
1707 }
1708
1709 static acpi_status
1710 acpi_video_bus_match(acpi_handle handle, u32 level, void *context,
1711                         void **return_value)
1712 {
1713         struct acpi_device *device = context;
1714         struct acpi_device *sibling;
1715         int result;
1716
1717         if (handle == device->handle)
1718                 return AE_CTRL_TERMINATE;
1719
1720         result = acpi_bus_get_device(handle, &sibling);
1721         if (result)
1722                 return AE_OK;
1723
1724         if (!strcmp(acpi_device_name(sibling), ACPI_VIDEO_BUS_NAME))
1725                         return AE_ALREADY_EXISTS;
1726
1727         return AE_OK;
1728 }
1729
1730 static int instance;
1731
1732 static int acpi_video_bus_add(struct acpi_device *device)
1733 {
1734         struct acpi_video_bus *video;
1735         struct input_dev *input;
1736         int error;
1737         acpi_status status;
1738
1739         if (device->handler)
1740                 return -EINVAL;
1741
1742         status = acpi_walk_namespace(ACPI_TYPE_DEVICE,
1743                                 device->parent->handle, 1,
1744                                 acpi_video_bus_match, NULL,
1745                                 device, NULL);
1746         if (status == AE_ALREADY_EXISTS) {
1747                 printk(KERN_WARNING FW_BUG
1748                         "Duplicate ACPI video bus devices for the"
1749                         " same VGA controller, please try module "
1750                         "parameter \"video.allow_duplicates=1\""
1751                         "if the current driver doesn't work.\n");
1752                 if (!allow_duplicates)
1753                         return -ENODEV;
1754         }
1755
1756         video = kzalloc(sizeof(struct acpi_video_bus), GFP_KERNEL);
1757         if (!video)
1758                 return -ENOMEM;
1759
1760         /* a hack to fix the duplicate name "VID" problem on T61 */
1761         if (!strcmp(device->pnp.bus_id, "VID")) {
1762                 if (instance)
1763                         device->pnp.bus_id[3] = '0' + instance;
1764                 instance ++;
1765         }
1766         /* a hack to fix the duplicate name "VGA" problem on Pa 3553 */
1767         if (!strcmp(device->pnp.bus_id, "VGA")) {
1768                 if (instance)
1769                         device->pnp.bus_id[3] = '0' + instance;
1770                 instance++;
1771         }
1772
1773         video->device = device;
1774         strcpy(acpi_device_name(device), ACPI_VIDEO_BUS_NAME);
1775         strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
1776         device->driver_data = video;
1777
1778         acpi_video_bus_find_cap(video);
1779         error = acpi_video_bus_check(video);
1780         if (error)
1781                 goto err_free_video;
1782
1783         mutex_init(&video->device_list_lock);
1784         INIT_LIST_HEAD(&video->video_device_list);
1785
1786         error = acpi_video_bus_get_devices(video, device);
1787         if (error)
1788                 goto err_put_video;
1789
1790         video->input = input = input_allocate_device();
1791         if (!input) {
1792                 error = -ENOMEM;
1793                 goto err_put_video;
1794         }
1795
1796         error = acpi_video_bus_start_devices(video);
1797         if (error)
1798                 goto err_free_input_dev;
1799
1800         snprintf(video->phys, sizeof(video->phys),
1801                 "%s/video/input0", acpi_device_hid(video->device));
1802
1803         input->name = acpi_device_name(video->device);
1804         input->phys = video->phys;
1805         input->id.bustype = BUS_HOST;
1806         input->id.product = 0x06;
1807         input->dev.parent = &device->dev;
1808         input->evbit[0] = BIT(EV_KEY);
1809         set_bit(KEY_SWITCHVIDEOMODE, input->keybit);
1810         set_bit(KEY_VIDEO_NEXT, input->keybit);
1811         set_bit(KEY_VIDEO_PREV, input->keybit);
1812         set_bit(KEY_BRIGHTNESS_CYCLE, input->keybit);
1813         set_bit(KEY_BRIGHTNESSUP, input->keybit);
1814         set_bit(KEY_BRIGHTNESSDOWN, input->keybit);
1815         set_bit(KEY_BRIGHTNESS_ZERO, input->keybit);
1816         set_bit(KEY_DISPLAY_OFF, input->keybit);
1817
1818         printk(KERN_INFO PREFIX "%s [%s] (multi-head: %s  rom: %s  post: %s)\n",
1819                ACPI_VIDEO_DEVICE_NAME, acpi_device_bid(device),
1820                video->flags.multihead ? "yes" : "no",
1821                video->flags.rom ? "yes" : "no",
1822                video->flags.post ? "yes" : "no");
1823
1824         video->pm_nb.notifier_call = acpi_video_resume;
1825         video->pm_nb.priority = 0;
1826         error = register_pm_notifier(&video->pm_nb);
1827         if (error)
1828                 goto err_stop_video;
1829
1830         error = input_register_device(input);
1831         if (error)
1832                 goto err_unregister_pm_notifier;
1833
1834         return 0;
1835
1836  err_unregister_pm_notifier:
1837         unregister_pm_notifier(&video->pm_nb);
1838  err_stop_video:
1839         acpi_video_bus_stop_devices(video);
1840  err_free_input_dev:
1841         input_free_device(input);
1842  err_put_video:
1843         acpi_video_bus_put_devices(video);
1844         kfree(video->attached_array);
1845  err_free_video:
1846         kfree(video);
1847         device->driver_data = NULL;
1848
1849         return error;
1850 }
1851
1852 static int acpi_video_bus_remove(struct acpi_device *device)
1853 {
1854         struct acpi_video_bus *video = NULL;
1855
1856
1857         if (!device || !acpi_driver_data(device))
1858                 return -EINVAL;
1859
1860         video = acpi_driver_data(device);
1861
1862         unregister_pm_notifier(&video->pm_nb);
1863
1864         acpi_video_bus_stop_devices(video);
1865         acpi_video_bus_put_devices(video);
1866
1867         input_unregister_device(video->input);
1868         kfree(video->attached_array);
1869         kfree(video);
1870
1871         return 0;
1872 }
1873
1874 static int __init is_i740(struct pci_dev *dev)
1875 {
1876         if (dev->device == 0x00D1)
1877                 return 1;
1878         if (dev->device == 0x7000)
1879                 return 1;
1880         return 0;
1881 }
1882
1883 static int __init intel_opregion_present(void)
1884 {
1885         int opregion = 0;
1886         struct pci_dev *dev = NULL;
1887         u32 address;
1888
1889         for_each_pci_dev(dev) {
1890                 if ((dev->class >> 8) != PCI_CLASS_DISPLAY_VGA)
1891                         continue;
1892                 if (dev->vendor != PCI_VENDOR_ID_INTEL)
1893                         continue;
1894                 /* We don't want to poke around undefined i740 registers */
1895                 if (is_i740(dev))
1896                         continue;
1897                 pci_read_config_dword(dev, 0xfc, &address);
1898                 if (!address)
1899                         continue;
1900                 opregion = 1;
1901         }
1902         return opregion;
1903 }
1904
1905 int acpi_video_register(void)
1906 {
1907         int result = 0;
1908         if (register_count) {
1909                 /*
1910                  * if the function of acpi_video_register is already called,
1911                  * don't register the acpi_vide_bus again and return no error.
1912                  */
1913                 return 0;
1914         }
1915
1916         result = acpi_bus_register_driver(&acpi_video_bus);
1917         if (result < 0)
1918                 return -ENODEV;
1919
1920         /*
1921          * When the acpi_video_bus is loaded successfully, increase
1922          * the counter reference.
1923          */
1924         register_count = 1;
1925
1926         return 0;
1927 }
1928 EXPORT_SYMBOL(acpi_video_register);
1929
1930 void acpi_video_unregister(void)
1931 {
1932         if (!register_count) {
1933                 /*
1934                  * If the acpi video bus is already unloaded, don't
1935                  * unload it again and return directly.
1936                  */
1937                 return;
1938         }
1939         acpi_bus_unregister_driver(&acpi_video_bus);
1940
1941         register_count = 0;
1942
1943         return;
1944 }
1945 EXPORT_SYMBOL(acpi_video_unregister);
1946
1947 /*
1948  * This is kind of nasty. Hardware using Intel chipsets may require
1949  * the video opregion code to be run first in order to initialise
1950  * state before any ACPI video calls are made. To handle this we defer
1951  * registration of the video class until the opregion code has run.
1952  */
1953
1954 static int __init acpi_video_init(void)
1955 {
1956         dmi_check_system(video_dmi_table);
1957
1958         if (intel_opregion_present())
1959                 return 0;
1960
1961         return acpi_video_register();
1962 }
1963
1964 static void __exit acpi_video_exit(void)
1965 {
1966         acpi_video_unregister();
1967
1968         return;
1969 }
1970
1971 module_init(acpi_video_init);
1972 module_exit(acpi_video_exit);