ACPI / video: Refactor and fix dmi_is_desktop()
[sfrench/cifs-2.6.git] / drivers / acpi / acpi_video.c
1 /*
2  *  video.c - ACPI Video Driver
3  *
4  *  Copyright (C) 2004 Luming Yu <luming.yu@intel.com>
5  *  Copyright (C) 2004 Bruno Ducrot <ducrot@poupinou.org>
6  *  Copyright (C) 2006 Thomas Tuttle <linux-kernel@ttuttle.net>
7  *
8  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9  *
10  *  This program is free software; you can redistribute it and/or modify
11  *  it under the terms of the GNU General Public License as published by
12  *  the Free Software Foundation; either version 2 of the License, or (at
13  *  your option) any later version.
14  *
15  *  This program is distributed in the hope that it will be useful, but
16  *  WITHOUT ANY WARRANTY; without even the implied warranty of
17  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
18  *  General Public License for more details.
19  *
20  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
21  */
22
23 #include <linux/kernel.h>
24 #include <linux/module.h>
25 #include <linux/init.h>
26 #include <linux/types.h>
27 #include <linux/list.h>
28 #include <linux/mutex.h>
29 #include <linux/input.h>
30 #include <linux/backlight.h>
31 #include <linux/thermal.h>
32 #include <linux/sort.h>
33 #include <linux/pci.h>
34 #include <linux/pci_ids.h>
35 #include <linux/slab.h>
36 #include <linux/dmi.h>
37 #include <linux/suspend.h>
38 #include <linux/acpi.h>
39 #include <acpi/video.h>
40 #include <linux/uaccess.h>
41
42 #define PREFIX "ACPI: "
43
44 #define ACPI_VIDEO_BUS_NAME             "Video Bus"
45 #define ACPI_VIDEO_DEVICE_NAME          "Video Device"
46
47 #define MAX_NAME_LEN    20
48
49 #define _COMPONENT              ACPI_VIDEO_COMPONENT
50 ACPI_MODULE_NAME("video");
51
52 MODULE_AUTHOR("Bruno Ducrot");
53 MODULE_DESCRIPTION("ACPI Video Driver");
54 MODULE_LICENSE("GPL");
55
56 static bool brightness_switch_enabled = true;
57 module_param(brightness_switch_enabled, bool, 0644);
58
59 /*
60  * By default, we don't allow duplicate ACPI video bus devices
61  * under the same VGA controller
62  */
63 static bool allow_duplicates;
64 module_param(allow_duplicates, bool, 0644);
65
66 static int disable_backlight_sysfs_if = -1;
67 module_param(disable_backlight_sysfs_if, int, 0444);
68
69 #define REPORT_OUTPUT_KEY_EVENTS                0x01
70 #define REPORT_BRIGHTNESS_KEY_EVENTS            0x02
71 static int report_key_events = -1;
72 module_param(report_key_events, int, 0644);
73 MODULE_PARM_DESC(report_key_events,
74         "0: none, 1: output changes, 2: brightness changes, 3: all");
75
76 /*
77  * Whether the struct acpi_video_device_attrib::device_id_scheme bit should be
78  * assumed even if not actually set.
79  */
80 static bool device_id_scheme = false;
81 module_param(device_id_scheme, bool, 0444);
82
83 static int only_lcd = -1;
84 module_param(only_lcd, int, 0444);
85
86 static int register_count;
87 static DEFINE_MUTEX(register_count_mutex);
88 static DEFINE_MUTEX(video_list_lock);
89 static LIST_HEAD(video_bus_head);
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 void acpi_video_detect_exit(void);
94
95 /*
96  * Indices in the _BCL method response: the first two items are special,
97  * the rest are all supported levels.
98  *
99  * See page 575 of the ACPI spec 3.0
100  */
101 enum acpi_video_level_idx {
102         ACPI_VIDEO_AC_LEVEL,            /* level when machine has full power */
103         ACPI_VIDEO_BATTERY_LEVEL,       /* level when machine is on batteries */
104         ACPI_VIDEO_FIRST_LEVEL,         /* actual supported levels begin here */
105 };
106
107 static const struct acpi_device_id video_device_ids[] = {
108         {ACPI_VIDEO_HID, 0},
109         {"", 0},
110 };
111 MODULE_DEVICE_TABLE(acpi, video_device_ids);
112
113 static struct acpi_driver acpi_video_bus = {
114         .name = "video",
115         .class = ACPI_VIDEO_CLASS,
116         .ids = video_device_ids,
117         .ops = {
118                 .add = acpi_video_bus_add,
119                 .remove = acpi_video_bus_remove,
120                 .notify = acpi_video_bus_notify,
121                 },
122 };
123
124 struct acpi_video_bus_flags {
125         u8 multihead:1;         /* can switch video heads */
126         u8 rom:1;               /* can retrieve a video rom */
127         u8 post:1;              /* can configure the head to */
128         u8 reserved:5;
129 };
130
131 struct acpi_video_bus_cap {
132         u8 _DOS:1;              /* Enable/Disable output switching */
133         u8 _DOD:1;              /* Enumerate all devices attached to display adapter */
134         u8 _ROM:1;              /* Get ROM Data */
135         u8 _GPD:1;              /* Get POST Device */
136         u8 _SPD:1;              /* Set POST Device */
137         u8 _VPO:1;              /* Video POST Options */
138         u8 reserved:2;
139 };
140
141 struct acpi_video_device_attrib {
142         u32 display_index:4;    /* A zero-based instance of the Display */
143         u32 display_port_attachment:4;  /* This field differentiates the display type */
144         u32 display_type:4;     /* Describe the specific type in use */
145         u32 vendor_specific:4;  /* Chipset Vendor Specific */
146         u32 bios_can_detect:1;  /* BIOS can detect the device */
147         u32 depend_on_vga:1;    /* Non-VGA output device whose power is related to
148                                    the VGA device. */
149         u32 pipe_id:3;          /* For VGA multiple-head devices. */
150         u32 reserved:10;        /* Must be 0 */
151
152         /*
153          * The device ID might not actually follow the scheme described by this
154          * struct acpi_video_device_attrib. If it does, then this bit
155          * device_id_scheme is set; otherwise, other fields should be ignored.
156          *
157          * (but also see the global flag device_id_scheme)
158          */
159         u32 device_id_scheme:1;
160 };
161
162 struct acpi_video_enumerated_device {
163         union {
164                 u32 int_val;
165                 struct acpi_video_device_attrib attrib;
166         } value;
167         struct acpi_video_device *bind_info;
168 };
169
170 struct acpi_video_bus {
171         struct acpi_device *device;
172         bool backlight_registered;
173         u8 dos_setting;
174         struct acpi_video_enumerated_device *attached_array;
175         u8 attached_count;
176         u8 child_count;
177         struct acpi_video_bus_cap cap;
178         struct acpi_video_bus_flags flags;
179         struct list_head video_device_list;
180         struct mutex device_list_lock;  /* protects video_device_list */
181         struct list_head entry;
182         struct input_dev *input;
183         char phys[32];  /* for input device */
184         struct notifier_block pm_nb;
185 };
186
187 struct acpi_video_device_flags {
188         u8 crt:1;
189         u8 lcd:1;
190         u8 tvout:1;
191         u8 dvi:1;
192         u8 bios:1;
193         u8 unknown:1;
194         u8 notify:1;
195         u8 reserved:1;
196 };
197
198 struct acpi_video_device_cap {
199         u8 _ADR:1;              /* Return the unique ID */
200         u8 _BCL:1;              /* Query list of brightness control levels supported */
201         u8 _BCM:1;              /* Set the brightness level */
202         u8 _BQC:1;              /* Get current brightness level */
203         u8 _BCQ:1;              /* Some buggy BIOS uses _BCQ instead of _BQC */
204         u8 _DDC:1;              /* Return the EDID for this device */
205 };
206
207 struct acpi_video_device {
208         unsigned long device_id;
209         struct acpi_video_device_flags flags;
210         struct acpi_video_device_cap cap;
211         struct list_head entry;
212         struct delayed_work switch_brightness_work;
213         int switch_brightness_event;
214         struct acpi_video_bus *video;
215         struct acpi_device *dev;
216         struct acpi_video_device_brightness *brightness;
217         struct backlight_device *backlight;
218         struct thermal_cooling_device *cooling_dev;
219 };
220
221 static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data);
222 static void acpi_video_device_rebind(struct acpi_video_bus *video);
223 static void acpi_video_device_bind(struct acpi_video_bus *video,
224                                    struct acpi_video_device *device);
225 static int acpi_video_device_enumerate(struct acpi_video_bus *video);
226 static int acpi_video_device_lcd_set_level(struct acpi_video_device *device,
227                         int level);
228 static int acpi_video_device_lcd_get_level_current(
229                         struct acpi_video_device *device,
230                         unsigned long long *level, bool raw);
231 static int acpi_video_get_next_level(struct acpi_video_device *device,
232                                      u32 level_current, u32 event);
233 static void acpi_video_switch_brightness(struct work_struct *work);
234
235 /* backlight device sysfs support */
236 static int acpi_video_get_brightness(struct backlight_device *bd)
237 {
238         unsigned long long cur_level;
239         int i;
240         struct acpi_video_device *vd = bl_get_data(bd);
241
242         if (acpi_video_device_lcd_get_level_current(vd, &cur_level, false))
243                 return -EINVAL;
244         for (i = ACPI_VIDEO_FIRST_LEVEL; i < vd->brightness->count; i++) {
245                 if (vd->brightness->levels[i] == cur_level)
246                         return i - ACPI_VIDEO_FIRST_LEVEL;
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 + ACPI_VIDEO_FIRST_LEVEL;
254         struct acpi_video_device *vd = bl_get_data(bd);
255
256         cancel_delayed_work(&vd->switch_brightness_work);
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,
268                                unsigned 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 - ACPI_VIDEO_FIRST_LEVEL - 1;
274         return 0;
275 }
276
277 static int video_get_cur_state(struct thermal_cooling_device *cooling_dev,
278                                unsigned 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 = ACPI_VIDEO_FIRST_LEVEL; offset < video->brightness->count;
288              offset++)
289                 if (level == video->brightness->levels[offset]) {
290                         *state = video->brightness->count - offset - 1;
291                         return 0;
292                 }
293
294         return -EINVAL;
295 }
296
297 static int
298 video_set_cur_state(struct thermal_cooling_device *cooling_dev, unsigned long state)
299 {
300         struct acpi_device *device = cooling_dev->devdata;
301         struct acpi_video_device *video = acpi_driver_data(device);
302         int level;
303
304         if (state >= video->brightness->count - ACPI_VIDEO_FIRST_LEVEL)
305                 return -EINVAL;
306
307         state = video->brightness->count - state;
308         level = video->brightness->levels[state - 1];
309         return acpi_video_device_lcd_set_level(video, level);
310 }
311
312 static const struct thermal_cooling_device_ops video_cooling_ops = {
313         .get_max_state = video_get_max_state,
314         .get_cur_state = video_get_cur_state,
315         .set_cur_state = video_set_cur_state,
316 };
317
318 /*
319  * --------------------------------------------------------------------------
320  *                             Video Management
321  * --------------------------------------------------------------------------
322  */
323
324 static int
325 acpi_video_device_lcd_query_levels(acpi_handle handle,
326                                    union acpi_object **levels)
327 {
328         int status;
329         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
330         union acpi_object *obj;
331
332
333         *levels = NULL;
334
335         status = acpi_evaluate_object(handle, "_BCL", NULL, &buffer);
336         if (!ACPI_SUCCESS(status))
337                 return status;
338         obj = (union acpi_object *)buffer.pointer;
339         if (!obj || (obj->type != ACPI_TYPE_PACKAGE)) {
340                 printk(KERN_ERR PREFIX "Invalid _BCL data\n");
341                 status = -EFAULT;
342                 goto err;
343         }
344
345         *levels = obj;
346
347         return 0;
348
349 err:
350         kfree(buffer.pointer);
351
352         return status;
353 }
354
355 static int
356 acpi_video_device_lcd_set_level(struct acpi_video_device *device, int level)
357 {
358         int status;
359         int state;
360
361         status = acpi_execute_simple_method(device->dev->handle,
362                                             "_BCM", level);
363         if (ACPI_FAILURE(status)) {
364                 ACPI_ERROR((AE_INFO, "Evaluating _BCM failed"));
365                 return -EIO;
366         }
367
368         device->brightness->curr = level;
369         for (state = ACPI_VIDEO_FIRST_LEVEL; state < device->brightness->count;
370              state++)
371                 if (level == device->brightness->levels[state]) {
372                         if (device->backlight)
373                                 device->backlight->props.brightness =
374                                         state - ACPI_VIDEO_FIRST_LEVEL;
375                         return 0;
376                 }
377
378         ACPI_ERROR((AE_INFO, "Current brightness invalid"));
379         return -EINVAL;
380 }
381
382 /*
383  * For some buggy _BQC methods, we need to add a constant value to
384  * the _BQC return value to get the actual current brightness level
385  */
386
387 static int bqc_offset_aml_bug_workaround;
388 static int video_set_bqc_offset(const struct dmi_system_id *d)
389 {
390         bqc_offset_aml_bug_workaround = 9;
391         return 0;
392 }
393
394 static int video_disable_backlight_sysfs_if(
395         const struct dmi_system_id *d)
396 {
397         if (disable_backlight_sysfs_if == -1)
398                 disable_backlight_sysfs_if = 1;
399         return 0;
400 }
401
402 static int video_set_device_id_scheme(const struct dmi_system_id *d)
403 {
404         device_id_scheme = true;
405         return 0;
406 }
407
408 static int video_enable_only_lcd(const struct dmi_system_id *d)
409 {
410         only_lcd = true;
411         return 0;
412 }
413
414 static int video_set_report_key_events(const struct dmi_system_id *id)
415 {
416         if (report_key_events == -1)
417                 report_key_events = (uintptr_t)id->driver_data;
418         return 0;
419 }
420
421 static const struct dmi_system_id video_dmi_table[] = {
422         /*
423          * Broken _BQC workaround http://bugzilla.kernel.org/show_bug.cgi?id=13121
424          */
425         {
426          .callback = video_set_bqc_offset,
427          .ident = "Acer Aspire 5720",
428          .matches = {
429                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
430                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5720"),
431                 },
432         },
433         {
434          .callback = video_set_bqc_offset,
435          .ident = "Acer Aspire 5710Z",
436          .matches = {
437                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
438                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5710Z"),
439                 },
440         },
441         {
442          .callback = video_set_bqc_offset,
443          .ident = "eMachines E510",
444          .matches = {
445                 DMI_MATCH(DMI_BOARD_VENDOR, "EMACHINES"),
446                 DMI_MATCH(DMI_PRODUCT_NAME, "eMachines E510"),
447                 },
448         },
449         {
450          .callback = video_set_bqc_offset,
451          .ident = "Acer Aspire 5315",
452          .matches = {
453                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
454                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5315"),
455                 },
456         },
457         {
458          .callback = video_set_bqc_offset,
459          .ident = "Acer Aspire 7720",
460          .matches = {
461                 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
462                 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 7720"),
463                 },
464         },
465
466         /*
467          * Some machines have a broken acpi-video interface for brightness
468          * control, but still need an acpi_video_device_lcd_set_level() call
469          * on resume to turn the backlight power on.  We Enable backlight
470          * control on these systems, but do not register a backlight sysfs
471          * as brightness control does not work.
472          */
473         {
474          /* https://bugzilla.kernel.org/show_bug.cgi?id=21012 */
475          .callback = video_disable_backlight_sysfs_if,
476          .ident = "Toshiba Portege R700",
477          .matches = {
478                 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
479                 DMI_MATCH(DMI_PRODUCT_NAME, "PORTEGE R700"),
480                 },
481         },
482         {
483          /* https://bugs.freedesktop.org/show_bug.cgi?id=82634 */
484          .callback = video_disable_backlight_sysfs_if,
485          .ident = "Toshiba Portege R830",
486          .matches = {
487                 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
488                 DMI_MATCH(DMI_PRODUCT_NAME, "PORTEGE R830"),
489                 },
490         },
491         {
492          /* https://bugzilla.kernel.org/show_bug.cgi?id=21012 */
493          .callback = video_disable_backlight_sysfs_if,
494          .ident = "Toshiba Satellite R830",
495          .matches = {
496                 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
497                 DMI_MATCH(DMI_PRODUCT_NAME, "SATELLITE R830"),
498                 },
499         },
500         /*
501          * Some machine's _DOD IDs don't have bit 31(Device ID Scheme) set
502          * but the IDs actually follow the Device ID Scheme.
503          */
504         {
505          /* https://bugzilla.kernel.org/show_bug.cgi?id=104121 */
506          .callback = video_set_device_id_scheme,
507          .ident = "ESPRIMO Mobile M9410",
508          .matches = {
509                 DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU SIEMENS"),
510                 DMI_MATCH(DMI_PRODUCT_NAME, "ESPRIMO Mobile M9410"),
511                 },
512         },
513         /*
514          * Some machines have multiple video output devices, but only the one
515          * that is the type of LCD can do the backlight control so we should not
516          * register backlight interface for other video output devices.
517          */
518         {
519          /* https://bugzilla.kernel.org/show_bug.cgi?id=104121 */
520          .callback = video_enable_only_lcd,
521          .ident = "ESPRIMO Mobile M9410",
522          .matches = {
523                 DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU SIEMENS"),
524                 DMI_MATCH(DMI_PRODUCT_NAME, "ESPRIMO Mobile M9410"),
525                 },
526         },
527         /*
528          * Some machines report wrong key events on the acpi-bus, suppress
529          * key event reporting on these.  Note this is only intended to work
530          * around events which are plain wrong. In some cases we get double
531          * events, in this case acpi-video is considered the canonical source
532          * and the events from the other source should be filtered. E.g.
533          * by calling acpi_video_handles_brightness_key_presses() from the
534          * vendor acpi/wmi driver or by using /lib/udev/hwdb.d/60-keyboard.hwdb
535          */
536         {
537          .callback = video_set_report_key_events,
538          .driver_data = (void *)((uintptr_t)REPORT_OUTPUT_KEY_EVENTS),
539          .ident = "Dell Vostro V131",
540          .matches = {
541                 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
542                 DMI_MATCH(DMI_PRODUCT_NAME, "Vostro V131"),
543                 },
544         },
545         {}
546 };
547
548 static unsigned long long
549 acpi_video_bqc_value_to_level(struct acpi_video_device *device,
550                               unsigned long long bqc_value)
551 {
552         unsigned long long level;
553
554         if (device->brightness->flags._BQC_use_index) {
555                 /*
556                  * _BQC returns an index that doesn't account for the first 2
557                  * items with special meaning (see enum acpi_video_level_idx),
558                  * so we need to compensate for that by offsetting ourselves
559                  */
560                 if (device->brightness->flags._BCL_reversed)
561                         bqc_value = device->brightness->count -
562                                 ACPI_VIDEO_FIRST_LEVEL - 1 - bqc_value;
563
564                 level = device->brightness->levels[bqc_value +
565                                                    ACPI_VIDEO_FIRST_LEVEL];
566         } else {
567                 level = bqc_value;
568         }
569
570         level += bqc_offset_aml_bug_workaround;
571
572         return level;
573 }
574
575 static int
576 acpi_video_device_lcd_get_level_current(struct acpi_video_device *device,
577                                         unsigned long long *level, bool raw)
578 {
579         acpi_status status = AE_OK;
580         int i;
581
582         if (device->cap._BQC || device->cap._BCQ) {
583                 char *buf = device->cap._BQC ? "_BQC" : "_BCQ";
584
585                 status = acpi_evaluate_integer(device->dev->handle, buf,
586                                                 NULL, level);
587                 if (ACPI_SUCCESS(status)) {
588                         if (raw) {
589                                 /*
590                                  * Caller has indicated he wants the raw
591                                  * value returned by _BQC, so don't furtherly
592                                  * mess with the value.
593                                  */
594                                 return 0;
595                         }
596
597                         *level = acpi_video_bqc_value_to_level(device, *level);
598
599                         for (i = ACPI_VIDEO_FIRST_LEVEL;
600                              i < device->brightness->count; i++)
601                                 if (device->brightness->levels[i] == *level) {
602                                         device->brightness->curr = *level;
603                                         return 0;
604                                 }
605                         /*
606                          * BQC returned an invalid level.
607                          * Stop using it.
608                          */
609                         ACPI_WARNING((AE_INFO,
610                                       "%s returned an invalid level",
611                                       buf));
612                         device->cap._BQC = device->cap._BCQ = 0;
613                 } else {
614                         /*
615                          * Fixme:
616                          * should we return an error or ignore this failure?
617                          * dev->brightness->curr is a cached value which stores
618                          * the correct current backlight level in most cases.
619                          * ACPI video backlight still works w/ buggy _BQC.
620                          * http://bugzilla.kernel.org/show_bug.cgi?id=12233
621                          */
622                         ACPI_WARNING((AE_INFO, "Evaluating %s failed", buf));
623                         device->cap._BQC = device->cap._BCQ = 0;
624                 }
625         }
626
627         *level = device->brightness->curr;
628         return 0;
629 }
630
631 static int
632 acpi_video_device_EDID(struct acpi_video_device *device,
633                        union acpi_object **edid, ssize_t length)
634 {
635         int status;
636         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
637         union acpi_object *obj;
638         union acpi_object arg0 = { ACPI_TYPE_INTEGER };
639         struct acpi_object_list args = { 1, &arg0 };
640
641
642         *edid = NULL;
643
644         if (!device)
645                 return -ENODEV;
646         if (length == 128)
647                 arg0.integer.value = 1;
648         else if (length == 256)
649                 arg0.integer.value = 2;
650         else
651                 return -EINVAL;
652
653         status = acpi_evaluate_object(device->dev->handle, "_DDC", &args, &buffer);
654         if (ACPI_FAILURE(status))
655                 return -ENODEV;
656
657         obj = buffer.pointer;
658
659         if (obj && obj->type == ACPI_TYPE_BUFFER)
660                 *edid = obj;
661         else {
662                 printk(KERN_ERR PREFIX "Invalid _DDC data\n");
663                 status = -EFAULT;
664                 kfree(obj);
665         }
666
667         return status;
668 }
669
670 /* bus */
671
672 /*
673  *  Arg:
674  *      video           : video bus device pointer
675  *      bios_flag       :
676  *              0.      The system BIOS should NOT automatically switch(toggle)
677  *                      the active display output.
678  *              1.      The system BIOS should automatically switch (toggle) the
679  *                      active display output. No switch event.
680  *              2.      The _DGS value should be locked.
681  *              3.      The system BIOS should not automatically switch (toggle) the
682  *                      active display output, but instead generate the display switch
683  *                      event notify code.
684  *      lcd_flag        :
685  *              0.      The system BIOS should automatically control the brightness level
686  *                      of the LCD when the power changes from AC to DC
687  *              1.      The system BIOS should NOT automatically control the brightness
688  *                      level of the LCD when the power changes from AC to DC.
689  *  Return Value:
690  *              -EINVAL wrong arg.
691  */
692
693 static int
694 acpi_video_bus_DOS(struct acpi_video_bus *video, int bios_flag, int lcd_flag)
695 {
696         acpi_status status;
697
698         if (!video->cap._DOS)
699                 return 0;
700
701         if (bios_flag < 0 || bios_flag > 3 || lcd_flag < 0 || lcd_flag > 1)
702                 return -EINVAL;
703         video->dos_setting = (lcd_flag << 2) | bios_flag;
704         status = acpi_execute_simple_method(video->device->handle, "_DOS",
705                                             (lcd_flag << 2) | bios_flag);
706         if (ACPI_FAILURE(status))
707                 return -EIO;
708
709         return 0;
710 }
711
712 /*
713  * Simple comparison function used to sort backlight levels.
714  */
715
716 static int
717 acpi_video_cmp_level(const void *a, const void *b)
718 {
719         return *(int *)a - *(int *)b;
720 }
721
722 /*
723  * Decides if _BQC/_BCQ for this system is usable
724  *
725  * We do this by changing the level first and then read out the current
726  * brightness level, if the value does not match, find out if it is using
727  * index. If not, clear the _BQC/_BCQ capability.
728  */
729 static int acpi_video_bqc_quirk(struct acpi_video_device *device,
730                                 int max_level, int current_level)
731 {
732         struct acpi_video_device_brightness *br = device->brightness;
733         int result;
734         unsigned long long level;
735         int test_level;
736
737         /* don't mess with existing known broken systems */
738         if (bqc_offset_aml_bug_workaround)
739                 return 0;
740
741         /*
742          * Some systems always report current brightness level as maximum
743          * through _BQC, we need to test another value for them. However,
744          * there is a subtlety:
745          *
746          * If the _BCL package ordering is descending, the first level
747          * (br->levels[2]) is likely to be 0, and if the number of levels
748          * matches the number of steps, we might confuse a returned level to
749          * mean the index.
750          *
751          * For example:
752          *
753          *     current_level = max_level = 100
754          *     test_level = 0
755          *     returned level = 100
756          *
757          * In this case 100 means the level, not the index, and _BCM failed.
758          * Still, if the _BCL package ordering is descending, the index of
759          * level 0 is also 100, so we assume _BQC is indexed, when it's not.
760          *
761          * This causes all _BQC calls to return bogus values causing weird
762          * behavior from the user's perspective.  For example:
763          *
764          * xbacklight -set 10; xbacklight -set 20;
765          *
766          * would flash to 90% and then slowly down to the desired level (20).
767          *
768          * The solution is simple; test anything other than the first level
769          * (e.g. 1).
770          */
771         test_level = current_level == max_level
772                 ? br->levels[ACPI_VIDEO_FIRST_LEVEL + 1]
773                 : max_level;
774
775         result = acpi_video_device_lcd_set_level(device, test_level);
776         if (result)
777                 return result;
778
779         result = acpi_video_device_lcd_get_level_current(device, &level, true);
780         if (result)
781                 return result;
782
783         if (level != test_level) {
784                 /* buggy _BQC found, need to find out if it uses index */
785                 if (level < br->count) {
786                         if (br->flags._BCL_reversed)
787                                 level = br->count - ACPI_VIDEO_FIRST_LEVEL - 1 - level;
788                         if (br->levels[level + ACPI_VIDEO_FIRST_LEVEL] == test_level)
789                                 br->flags._BQC_use_index = 1;
790                 }
791
792                 if (!br->flags._BQC_use_index)
793                         device->cap._BQC = device->cap._BCQ = 0;
794         }
795
796         return 0;
797 }
798
799 int acpi_video_get_levels(struct acpi_device *device,
800                           struct acpi_video_device_brightness **dev_br,
801                           int *pmax_level)
802 {
803         union acpi_object *obj = NULL;
804         int i, max_level = 0, count = 0, level_ac_battery = 0;
805         union acpi_object *o;
806         struct acpi_video_device_brightness *br = NULL;
807         int result = 0;
808         u32 value;
809
810         if (!ACPI_SUCCESS(acpi_video_device_lcd_query_levels(device->handle,
811                                                                 &obj))) {
812                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Could not query available "
813                                                 "LCD brightness level\n"));
814                 result = -ENODEV;
815                 goto out;
816         }
817
818         if (obj->package.count < ACPI_VIDEO_FIRST_LEVEL) {
819                 result = -EINVAL;
820                 goto out;
821         }
822
823         br = kzalloc(sizeof(*br), GFP_KERNEL);
824         if (!br) {
825                 printk(KERN_ERR "can't allocate memory\n");
826                 result = -ENOMEM;
827                 goto out;
828         }
829
830         /*
831          * Note that we have to reserve 2 extra items (ACPI_VIDEO_FIRST_LEVEL),
832          * in order to account for buggy BIOS which don't export the first two
833          * special levels (see below)
834          */
835         br->levels = kmalloc_array(obj->package.count + ACPI_VIDEO_FIRST_LEVEL,
836                                    sizeof(*br->levels),
837                                    GFP_KERNEL);
838         if (!br->levels) {
839                 result = -ENOMEM;
840                 goto out_free;
841         }
842
843         for (i = 0; i < obj->package.count; i++) {
844                 o = (union acpi_object *)&obj->package.elements[i];
845                 if (o->type != ACPI_TYPE_INTEGER) {
846                         printk(KERN_ERR PREFIX "Invalid data\n");
847                         continue;
848                 }
849                 value = (u32) o->integer.value;
850                 /* Skip duplicate entries */
851                 if (count > ACPI_VIDEO_FIRST_LEVEL
852                     && br->levels[count - 1] == value)
853                         continue;
854
855                 br->levels[count] = value;
856
857                 if (br->levels[count] > max_level)
858                         max_level = br->levels[count];
859                 count++;
860         }
861
862         /*
863          * some buggy BIOS don't export the levels
864          * when machine is on AC/Battery in _BCL package.
865          * In this case, the first two elements in _BCL packages
866          * are also supported brightness levels that OS should take care of.
867          */
868         for (i = ACPI_VIDEO_FIRST_LEVEL; i < count; i++) {
869                 if (br->levels[i] == br->levels[ACPI_VIDEO_AC_LEVEL])
870                         level_ac_battery++;
871                 if (br->levels[i] == br->levels[ACPI_VIDEO_BATTERY_LEVEL])
872                         level_ac_battery++;
873         }
874
875         if (level_ac_battery < ACPI_VIDEO_FIRST_LEVEL) {
876                 level_ac_battery = ACPI_VIDEO_FIRST_LEVEL - level_ac_battery;
877                 br->flags._BCL_no_ac_battery_levels = 1;
878                 for (i = (count - 1 + level_ac_battery);
879                      i >= ACPI_VIDEO_FIRST_LEVEL; i--)
880                         br->levels[i] = br->levels[i - level_ac_battery];
881                 count += level_ac_battery;
882         } else if (level_ac_battery > ACPI_VIDEO_FIRST_LEVEL)
883                 ACPI_ERROR((AE_INFO, "Too many duplicates in _BCL package"));
884
885         /* Check if the _BCL package is in a reversed order */
886         if (max_level == br->levels[ACPI_VIDEO_FIRST_LEVEL]) {
887                 br->flags._BCL_reversed = 1;
888                 sort(&br->levels[ACPI_VIDEO_FIRST_LEVEL],
889                      count - ACPI_VIDEO_FIRST_LEVEL,
890                      sizeof(br->levels[ACPI_VIDEO_FIRST_LEVEL]),
891                      acpi_video_cmp_level, NULL);
892         } else if (max_level != br->levels[count - 1])
893                 ACPI_ERROR((AE_INFO,
894                             "Found unordered _BCL package"));
895
896         br->count = count;
897         *dev_br = br;
898         if (pmax_level)
899                 *pmax_level = max_level;
900
901 out:
902         kfree(obj);
903         return result;
904 out_free:
905         kfree(br);
906         goto out;
907 }
908 EXPORT_SYMBOL(acpi_video_get_levels);
909
910 /*
911  *  Arg:
912  *      device  : video output device (LCD, CRT, ..)
913  *
914  *  Return Value:
915  *      Maximum brightness level
916  *
917  *  Allocate and initialize device->brightness.
918  */
919
920 static int
921 acpi_video_init_brightness(struct acpi_video_device *device)
922 {
923         int i, max_level = 0;
924         unsigned long long level, level_old;
925         struct acpi_video_device_brightness *br = NULL;
926         int result = -EINVAL;
927
928         result = acpi_video_get_levels(device->dev, &br, &max_level);
929         if (result)
930                 return result;
931         device->brightness = br;
932
933         /* _BQC uses INDEX while _BCL uses VALUE in some laptops */
934         br->curr = level = max_level;
935
936         if (!device->cap._BQC)
937                 goto set_level;
938
939         result = acpi_video_device_lcd_get_level_current(device,
940                                                          &level_old, true);
941         if (result)
942                 goto out_free_levels;
943
944         result = acpi_video_bqc_quirk(device, max_level, level_old);
945         if (result)
946                 goto out_free_levels;
947         /*
948          * cap._BQC may get cleared due to _BQC is found to be broken
949          * in acpi_video_bqc_quirk, so check again here.
950          */
951         if (!device->cap._BQC)
952                 goto set_level;
953
954         level = acpi_video_bqc_value_to_level(device, level_old);
955         /*
956          * On some buggy laptops, _BQC returns an uninitialized
957          * value when invoked for the first time, i.e.
958          * level_old is invalid (no matter whether it's a level
959          * or an index). Set the backlight to max_level in this case.
960          */
961         for (i = ACPI_VIDEO_FIRST_LEVEL; i < br->count; i++)
962                 if (level == br->levels[i])
963                         break;
964         if (i == br->count || !level)
965                 level = max_level;
966
967 set_level:
968         result = acpi_video_device_lcd_set_level(device, level);
969         if (result)
970                 goto out_free_levels;
971
972         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
973                           "found %d brightness levels\n",
974                           br->count - ACPI_VIDEO_FIRST_LEVEL));
975         return 0;
976
977 out_free_levels:
978         kfree(br->levels);
979         kfree(br);
980         device->brightness = NULL;
981         return result;
982 }
983
984 /*
985  *  Arg:
986  *      device  : video output device (LCD, CRT, ..)
987  *
988  *  Return Value:
989  *      None
990  *
991  *  Find out all required AML methods defined under the output
992  *  device.
993  */
994
995 static void acpi_video_device_find_cap(struct acpi_video_device *device)
996 {
997         if (acpi_has_method(device->dev->handle, "_ADR"))
998                 device->cap._ADR = 1;
999         if (acpi_has_method(device->dev->handle, "_BCL"))
1000                 device->cap._BCL = 1;
1001         if (acpi_has_method(device->dev->handle, "_BCM"))
1002                 device->cap._BCM = 1;
1003         if (acpi_has_method(device->dev->handle, "_BQC")) {
1004                 device->cap._BQC = 1;
1005         } else if (acpi_has_method(device->dev->handle, "_BCQ")) {
1006                 printk(KERN_WARNING FW_BUG "_BCQ is used instead of _BQC\n");
1007                 device->cap._BCQ = 1;
1008         }
1009
1010         if (acpi_has_method(device->dev->handle, "_DDC"))
1011                 device->cap._DDC = 1;
1012 }
1013
1014 /*
1015  *  Arg:
1016  *      device  : video output device (VGA)
1017  *
1018  *  Return Value:
1019  *      None
1020  *
1021  *  Find out all required AML methods defined under the video bus device.
1022  */
1023
1024 static void acpi_video_bus_find_cap(struct acpi_video_bus *video)
1025 {
1026         if (acpi_has_method(video->device->handle, "_DOS"))
1027                 video->cap._DOS = 1;
1028         if (acpi_has_method(video->device->handle, "_DOD"))
1029                 video->cap._DOD = 1;
1030         if (acpi_has_method(video->device->handle, "_ROM"))
1031                 video->cap._ROM = 1;
1032         if (acpi_has_method(video->device->handle, "_GPD"))
1033                 video->cap._GPD = 1;
1034         if (acpi_has_method(video->device->handle, "_SPD"))
1035                 video->cap._SPD = 1;
1036         if (acpi_has_method(video->device->handle, "_VPO"))
1037                 video->cap._VPO = 1;
1038 }
1039
1040 /*
1041  * Check whether the video bus device has required AML method to
1042  * support the desired features
1043  */
1044
1045 static int acpi_video_bus_check(struct acpi_video_bus *video)
1046 {
1047         acpi_status status = -ENOENT;
1048         struct pci_dev *dev;
1049
1050         if (!video)
1051                 return -EINVAL;
1052
1053         dev = acpi_get_pci_dev(video->device->handle);
1054         if (!dev)
1055                 return -ENODEV;
1056         pci_dev_put(dev);
1057
1058         /*
1059          * Since there is no HID, CID and so on for VGA driver, we have
1060          * to check well known required nodes.
1061          */
1062
1063         /* Does this device support video switching? */
1064         if (video->cap._DOS || video->cap._DOD) {
1065                 if (!video->cap._DOS) {
1066                         printk(KERN_WARNING FW_BUG
1067                                 "ACPI(%s) defines _DOD but not _DOS\n",
1068                                 acpi_device_bid(video->device));
1069                 }
1070                 video->flags.multihead = 1;
1071                 status = 0;
1072         }
1073
1074         /* Does this device support retrieving a video ROM? */
1075         if (video->cap._ROM) {
1076                 video->flags.rom = 1;
1077                 status = 0;
1078         }
1079
1080         /* Does this device support configuring which video device to POST? */
1081         if (video->cap._GPD && video->cap._SPD && video->cap._VPO) {
1082                 video->flags.post = 1;
1083                 status = 0;
1084         }
1085
1086         return status;
1087 }
1088
1089 /*
1090  * --------------------------------------------------------------------------
1091  *                               Driver Interface
1092  * --------------------------------------------------------------------------
1093  */
1094
1095 /* device interface */
1096 static struct acpi_video_device_attrib *
1097 acpi_video_get_device_attr(struct acpi_video_bus *video, unsigned long device_id)
1098 {
1099         struct acpi_video_enumerated_device *ids;
1100         int i;
1101
1102         for (i = 0; i < video->attached_count; i++) {
1103                 ids = &video->attached_array[i];
1104                 if ((ids->value.int_val & 0xffff) == device_id)
1105                         return &ids->value.attrib;
1106         }
1107
1108         return NULL;
1109 }
1110
1111 static int
1112 acpi_video_get_device_type(struct acpi_video_bus *video,
1113                            unsigned long device_id)
1114 {
1115         struct acpi_video_enumerated_device *ids;
1116         int i;
1117
1118         for (i = 0; i < video->attached_count; i++) {
1119                 ids = &video->attached_array[i];
1120                 if ((ids->value.int_val & 0xffff) == device_id)
1121                         return ids->value.int_val;
1122         }
1123
1124         return 0;
1125 }
1126
1127 static int
1128 acpi_video_bus_get_one_device(struct acpi_device *device,
1129                               struct acpi_video_bus *video)
1130 {
1131         unsigned long long device_id;
1132         int status, device_type;
1133         struct acpi_video_device *data;
1134         struct acpi_video_device_attrib *attribute;
1135
1136         status =
1137             acpi_evaluate_integer(device->handle, "_ADR", NULL, &device_id);
1138         /* Some device omits _ADR, we skip them instead of fail */
1139         if (ACPI_FAILURE(status))
1140                 return 0;
1141
1142         data = kzalloc(sizeof(struct acpi_video_device), GFP_KERNEL);
1143         if (!data)
1144                 return -ENOMEM;
1145
1146         strcpy(acpi_device_name(device), ACPI_VIDEO_DEVICE_NAME);
1147         strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
1148         device->driver_data = data;
1149
1150         data->device_id = device_id;
1151         data->video = video;
1152         data->dev = device;
1153         INIT_DELAYED_WORK(&data->switch_brightness_work,
1154                           acpi_video_switch_brightness);
1155
1156         attribute = acpi_video_get_device_attr(video, device_id);
1157
1158         if (attribute && (attribute->device_id_scheme || device_id_scheme)) {
1159                 switch (attribute->display_type) {
1160                 case ACPI_VIDEO_DISPLAY_CRT:
1161                         data->flags.crt = 1;
1162                         break;
1163                 case ACPI_VIDEO_DISPLAY_TV:
1164                         data->flags.tvout = 1;
1165                         break;
1166                 case ACPI_VIDEO_DISPLAY_DVI:
1167                         data->flags.dvi = 1;
1168                         break;
1169                 case ACPI_VIDEO_DISPLAY_LCD:
1170                         data->flags.lcd = 1;
1171                         break;
1172                 default:
1173                         data->flags.unknown = 1;
1174                         break;
1175                 }
1176                 if (attribute->bios_can_detect)
1177                         data->flags.bios = 1;
1178         } else {
1179                 /* Check for legacy IDs */
1180                 device_type = acpi_video_get_device_type(video, device_id);
1181                 /* Ignore bits 16 and 18-20 */
1182                 switch (device_type & 0xffe2ffff) {
1183                 case ACPI_VIDEO_DISPLAY_LEGACY_MONITOR:
1184                         data->flags.crt = 1;
1185                         break;
1186                 case ACPI_VIDEO_DISPLAY_LEGACY_PANEL:
1187                         data->flags.lcd = 1;
1188                         break;
1189                 case ACPI_VIDEO_DISPLAY_LEGACY_TV:
1190                         data->flags.tvout = 1;
1191                         break;
1192                 default:
1193                         data->flags.unknown = 1;
1194                 }
1195         }
1196
1197         acpi_video_device_bind(video, data);
1198         acpi_video_device_find_cap(data);
1199
1200         mutex_lock(&video->device_list_lock);
1201         list_add_tail(&data->entry, &video->video_device_list);
1202         mutex_unlock(&video->device_list_lock);
1203
1204         return status;
1205 }
1206
1207 /*
1208  *  Arg:
1209  *      video   : video bus device
1210  *
1211  *  Return:
1212  *      none
1213  *
1214  *  Enumerate the video device list of the video bus,
1215  *  bind the ids with the corresponding video devices
1216  *  under the video bus.
1217  */
1218
1219 static void acpi_video_device_rebind(struct acpi_video_bus *video)
1220 {
1221         struct acpi_video_device *dev;
1222
1223         mutex_lock(&video->device_list_lock);
1224
1225         list_for_each_entry(dev, &video->video_device_list, entry)
1226                 acpi_video_device_bind(video, dev);
1227
1228         mutex_unlock(&video->device_list_lock);
1229 }
1230
1231 /*
1232  *  Arg:
1233  *      video   : video bus device
1234  *      device  : video output device under the video
1235  *              bus
1236  *
1237  *  Return:
1238  *      none
1239  *
1240  *  Bind the ids with the corresponding video devices
1241  *  under the video bus.
1242  */
1243
1244 static void
1245 acpi_video_device_bind(struct acpi_video_bus *video,
1246                        struct acpi_video_device *device)
1247 {
1248         struct acpi_video_enumerated_device *ids;
1249         int i;
1250
1251         for (i = 0; i < video->attached_count; i++) {
1252                 ids = &video->attached_array[i];
1253                 if (device->device_id == (ids->value.int_val & 0xffff)) {
1254                         ids->bind_info = device;
1255                         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "device_bind %d\n", i));
1256                 }
1257         }
1258 }
1259
1260 static bool acpi_video_device_in_dod(struct acpi_video_device *device)
1261 {
1262         struct acpi_video_bus *video = device->video;
1263         int i;
1264
1265         /*
1266          * If we have a broken _DOD or we have more than 8 output devices
1267          * under the graphics controller node that we can't proper deal with
1268          * in the operation region code currently, no need to test.
1269          */
1270         if (!video->attached_count || video->child_count > 8)
1271                 return true;
1272
1273         for (i = 0; i < video->attached_count; i++) {
1274                 if ((video->attached_array[i].value.int_val & 0xfff) ==
1275                     (device->device_id & 0xfff))
1276                         return true;
1277         }
1278
1279         return false;
1280 }
1281
1282 /*
1283  *  Arg:
1284  *      video   : video bus device
1285  *
1286  *  Return:
1287  *      < 0     : error
1288  *
1289  *  Call _DOD to enumerate all devices attached to display adapter
1290  *
1291  */
1292
1293 static int acpi_video_device_enumerate(struct acpi_video_bus *video)
1294 {
1295         int status;
1296         int count;
1297         int i;
1298         struct acpi_video_enumerated_device *active_list;
1299         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1300         union acpi_object *dod = NULL;
1301         union acpi_object *obj;
1302
1303         if (!video->cap._DOD)
1304                 return AE_NOT_EXIST;
1305
1306         status = acpi_evaluate_object(video->device->handle, "_DOD", NULL, &buffer);
1307         if (!ACPI_SUCCESS(status)) {
1308                 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _DOD"));
1309                 return status;
1310         }
1311
1312         dod = buffer.pointer;
1313         if (!dod || (dod->type != ACPI_TYPE_PACKAGE)) {
1314                 ACPI_EXCEPTION((AE_INFO, status, "Invalid _DOD data"));
1315                 status = -EFAULT;
1316                 goto out;
1317         }
1318
1319         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d video heads in _DOD\n",
1320                           dod->package.count));
1321
1322         active_list = kcalloc(1 + dod->package.count,
1323                               sizeof(struct acpi_video_enumerated_device),
1324                               GFP_KERNEL);
1325         if (!active_list) {
1326                 status = -ENOMEM;
1327                 goto out;
1328         }
1329
1330         count = 0;
1331         for (i = 0; i < dod->package.count; i++) {
1332                 obj = &dod->package.elements[i];
1333
1334                 if (obj->type != ACPI_TYPE_INTEGER) {
1335                         printk(KERN_ERR PREFIX
1336                                 "Invalid _DOD data in element %d\n", i);
1337                         continue;
1338                 }
1339
1340                 active_list[count].value.int_val = obj->integer.value;
1341                 active_list[count].bind_info = NULL;
1342                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "dod element[%d] = %d\n", i,
1343                                   (int)obj->integer.value));
1344                 count++;
1345         }
1346
1347         kfree(video->attached_array);
1348
1349         video->attached_array = active_list;
1350         video->attached_count = count;
1351
1352 out:
1353         kfree(buffer.pointer);
1354         return status;
1355 }
1356
1357 static int
1358 acpi_video_get_next_level(struct acpi_video_device *device,
1359                           u32 level_current, u32 event)
1360 {
1361         int min, max, min_above, max_below, i, l, delta = 255;
1362         max = max_below = 0;
1363         min = min_above = 255;
1364         /* Find closest level to level_current */
1365         for (i = ACPI_VIDEO_FIRST_LEVEL; i < device->brightness->count; i++) {
1366                 l = device->brightness->levels[i];
1367                 if (abs(l - level_current) < abs(delta)) {
1368                         delta = l - level_current;
1369                         if (!delta)
1370                                 break;
1371                 }
1372         }
1373         /* Ajust level_current to closest available level */
1374         level_current += delta;
1375         for (i = ACPI_VIDEO_FIRST_LEVEL; i < device->brightness->count; i++) {
1376                 l = device->brightness->levels[i];
1377                 if (l < min)
1378                         min = l;
1379                 if (l > max)
1380                         max = l;
1381                 if (l < min_above && l > level_current)
1382                         min_above = l;
1383                 if (l > max_below && l < level_current)
1384                         max_below = l;
1385         }
1386
1387         switch (event) {
1388         case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:
1389                 return (level_current < max) ? min_above : min;
1390         case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:
1391                 return (level_current < max) ? min_above : max;
1392         case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:
1393                 return (level_current > min) ? max_below : min;
1394         case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS:
1395         case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:
1396                 return 0;
1397         default:
1398                 return level_current;
1399         }
1400 }
1401
1402 static void
1403 acpi_video_switch_brightness(struct work_struct *work)
1404 {
1405         struct acpi_video_device *device = container_of(to_delayed_work(work),
1406                              struct acpi_video_device, switch_brightness_work);
1407         unsigned long long level_current, level_next;
1408         int event = device->switch_brightness_event;
1409         int result = -EINVAL;
1410
1411         /* no warning message if acpi_backlight=vendor or a quirk is used */
1412         if (!device->backlight)
1413                 return;
1414
1415         if (!device->brightness)
1416                 goto out;
1417
1418         result = acpi_video_device_lcd_get_level_current(device,
1419                                                          &level_current,
1420                                                          false);
1421         if (result)
1422                 goto out;
1423
1424         level_next = acpi_video_get_next_level(device, level_current, event);
1425
1426         result = acpi_video_device_lcd_set_level(device, level_next);
1427
1428         if (!result)
1429                 backlight_force_update(device->backlight,
1430                                        BACKLIGHT_UPDATE_HOTKEY);
1431
1432 out:
1433         if (result)
1434                 printk(KERN_ERR PREFIX "Failed to switch the brightness\n");
1435 }
1436
1437 int acpi_video_get_edid(struct acpi_device *device, int type, int device_id,
1438                         void **edid)
1439 {
1440         struct acpi_video_bus *video;
1441         struct acpi_video_device *video_device;
1442         union acpi_object *buffer = NULL;
1443         acpi_status status;
1444         int i, length;
1445
1446         if (!device || !acpi_driver_data(device))
1447                 return -EINVAL;
1448
1449         video = acpi_driver_data(device);
1450
1451         for (i = 0; i < video->attached_count; i++) {
1452                 video_device = video->attached_array[i].bind_info;
1453                 length = 256;
1454
1455                 if (!video_device)
1456                         continue;
1457
1458                 if (!video_device->cap._DDC)
1459                         continue;
1460
1461                 if (type) {
1462                         switch (type) {
1463                         case ACPI_VIDEO_DISPLAY_CRT:
1464                                 if (!video_device->flags.crt)
1465                                         continue;
1466                                 break;
1467                         case ACPI_VIDEO_DISPLAY_TV:
1468                                 if (!video_device->flags.tvout)
1469                                         continue;
1470                                 break;
1471                         case ACPI_VIDEO_DISPLAY_DVI:
1472                                 if (!video_device->flags.dvi)
1473                                         continue;
1474                                 break;
1475                         case ACPI_VIDEO_DISPLAY_LCD:
1476                                 if (!video_device->flags.lcd)
1477                                         continue;
1478                                 break;
1479                         }
1480                 } else if (video_device->device_id != device_id) {
1481                         continue;
1482                 }
1483
1484                 status = acpi_video_device_EDID(video_device, &buffer, length);
1485
1486                 if (ACPI_FAILURE(status) || !buffer ||
1487                     buffer->type != ACPI_TYPE_BUFFER) {
1488                         length = 128;
1489                         status = acpi_video_device_EDID(video_device, &buffer,
1490                                                         length);
1491                         if (ACPI_FAILURE(status) || !buffer ||
1492                             buffer->type != ACPI_TYPE_BUFFER) {
1493                                 continue;
1494                         }
1495                 }
1496
1497                 *edid = buffer->buffer.pointer;
1498                 return length;
1499         }
1500
1501         return -ENODEV;
1502 }
1503 EXPORT_SYMBOL(acpi_video_get_edid);
1504
1505 static int
1506 acpi_video_bus_get_devices(struct acpi_video_bus *video,
1507                            struct acpi_device *device)
1508 {
1509         int status = 0;
1510         struct acpi_device *dev;
1511
1512         /*
1513          * There are systems where video module known to work fine regardless
1514          * of broken _DOD and ignoring returned value here doesn't cause
1515          * any issues later.
1516          */
1517         acpi_video_device_enumerate(video);
1518
1519         list_for_each_entry(dev, &device->children, node) {
1520
1521                 status = acpi_video_bus_get_one_device(dev, video);
1522                 if (status) {
1523                         dev_err(&dev->dev, "Can't attach device\n");
1524                         break;
1525                 }
1526                 video->child_count++;
1527         }
1528         return status;
1529 }
1530
1531 /* acpi_video interface */
1532
1533 /*
1534  * Win8 requires setting bit2 of _DOS to let firmware know it shouldn't
1535  * preform any automatic brightness change on receiving a notification.
1536  */
1537 static int acpi_video_bus_start_devices(struct acpi_video_bus *video)
1538 {
1539         return acpi_video_bus_DOS(video, 0,
1540                                   acpi_osi_is_win8() ? 1 : 0);
1541 }
1542
1543 static int acpi_video_bus_stop_devices(struct acpi_video_bus *video)
1544 {
1545         return acpi_video_bus_DOS(video, 0,
1546                                   acpi_osi_is_win8() ? 0 : 1);
1547 }
1548
1549 static void acpi_video_bus_notify(struct acpi_device *device, u32 event)
1550 {
1551         struct acpi_video_bus *video = acpi_driver_data(device);
1552         struct input_dev *input;
1553         int keycode = 0;
1554
1555         if (!video || !video->input)
1556                 return;
1557
1558         input = video->input;
1559
1560         switch (event) {
1561         case ACPI_VIDEO_NOTIFY_SWITCH:  /* User requested a switch,
1562                                          * most likely via hotkey. */
1563                 keycode = KEY_SWITCHVIDEOMODE;
1564                 break;
1565
1566         case ACPI_VIDEO_NOTIFY_PROBE:   /* User plugged in or removed a video
1567                                          * connector. */
1568                 acpi_video_device_enumerate(video);
1569                 acpi_video_device_rebind(video);
1570                 keycode = KEY_SWITCHVIDEOMODE;
1571                 break;
1572
1573         case ACPI_VIDEO_NOTIFY_CYCLE:   /* Cycle Display output hotkey pressed. */
1574                 keycode = KEY_SWITCHVIDEOMODE;
1575                 break;
1576         case ACPI_VIDEO_NOTIFY_NEXT_OUTPUT:     /* Next Display output hotkey pressed. */
1577                 keycode = KEY_VIDEO_NEXT;
1578                 break;
1579         case ACPI_VIDEO_NOTIFY_PREV_OUTPUT:     /* previous Display output hotkey pressed. */
1580                 keycode = KEY_VIDEO_PREV;
1581                 break;
1582
1583         default:
1584                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1585                                   "Unsupported event [0x%x]\n", event));
1586                 break;
1587         }
1588
1589         if (acpi_notifier_call_chain(device, event, 0))
1590                 /* Something vetoed the keypress. */
1591                 keycode = 0;
1592
1593         if (keycode && (report_key_events & REPORT_OUTPUT_KEY_EVENTS)) {
1594                 input_report_key(input, keycode, 1);
1595                 input_sync(input);
1596                 input_report_key(input, keycode, 0);
1597                 input_sync(input);
1598         }
1599
1600         return;
1601 }
1602
1603 static void brightness_switch_event(struct acpi_video_device *video_device,
1604                                     u32 event)
1605 {
1606         if (!brightness_switch_enabled)
1607                 return;
1608
1609         video_device->switch_brightness_event = event;
1610         schedule_delayed_work(&video_device->switch_brightness_work, HZ / 10);
1611 }
1612
1613 static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data)
1614 {
1615         struct acpi_video_device *video_device = data;
1616         struct acpi_device *device = NULL;
1617         struct acpi_video_bus *bus;
1618         struct input_dev *input;
1619         int keycode = 0;
1620
1621         if (!video_device)
1622                 return;
1623
1624         device = video_device->dev;
1625         bus = video_device->video;
1626         input = bus->input;
1627
1628         switch (event) {
1629         case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:        /* Cycle brightness */
1630                 brightness_switch_event(video_device, event);
1631                 keycode = KEY_BRIGHTNESS_CYCLE;
1632                 break;
1633         case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:  /* Increase brightness */
1634                 brightness_switch_event(video_device, event);
1635                 keycode = KEY_BRIGHTNESSUP;
1636                 break;
1637         case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:  /* Decrease brightness */
1638                 brightness_switch_event(video_device, event);
1639                 keycode = KEY_BRIGHTNESSDOWN;
1640                 break;
1641         case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS: /* zero brightness */
1642                 brightness_switch_event(video_device, event);
1643                 keycode = KEY_BRIGHTNESS_ZERO;
1644                 break;
1645         case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:     /* display device off */
1646                 brightness_switch_event(video_device, event);
1647                 keycode = KEY_DISPLAY_OFF;
1648                 break;
1649         default:
1650                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1651                                   "Unsupported event [0x%x]\n", event));
1652                 break;
1653         }
1654
1655         acpi_notifier_call_chain(device, event, 0);
1656
1657         if (keycode && (report_key_events & REPORT_BRIGHTNESS_KEY_EVENTS)) {
1658                 input_report_key(input, keycode, 1);
1659                 input_sync(input);
1660                 input_report_key(input, keycode, 0);
1661                 input_sync(input);
1662         }
1663
1664         return;
1665 }
1666
1667 static int acpi_video_resume(struct notifier_block *nb,
1668                                 unsigned long val, void *ign)
1669 {
1670         struct acpi_video_bus *video;
1671         struct acpi_video_device *video_device;
1672         int i;
1673
1674         switch (val) {
1675         case PM_HIBERNATION_PREPARE:
1676         case PM_SUSPEND_PREPARE:
1677         case PM_RESTORE_PREPARE:
1678                 return NOTIFY_DONE;
1679         }
1680
1681         video = container_of(nb, struct acpi_video_bus, pm_nb);
1682
1683         dev_info(&video->device->dev, "Restoring backlight state\n");
1684
1685         for (i = 0; i < video->attached_count; i++) {
1686                 video_device = video->attached_array[i].bind_info;
1687                 if (video_device && video_device->brightness)
1688                         acpi_video_device_lcd_set_level(video_device,
1689                                         video_device->brightness->curr);
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 void acpi_video_dev_register_backlight(struct acpi_video_device *device)
1717 {
1718         struct backlight_properties props;
1719         struct pci_dev *pdev;
1720         acpi_handle acpi_parent;
1721         struct device *parent = NULL;
1722         int result;
1723         static int count;
1724         char *name;
1725
1726         result = acpi_video_init_brightness(device);
1727         if (result)
1728                 return;
1729
1730         if (disable_backlight_sysfs_if > 0)
1731                 return;
1732
1733         name = kasprintf(GFP_KERNEL, "acpi_video%d", count);
1734         if (!name)
1735                 return;
1736         count++;
1737
1738         acpi_get_parent(device->dev->handle, &acpi_parent);
1739
1740         pdev = acpi_get_pci_dev(acpi_parent);
1741         if (pdev) {
1742                 parent = &pdev->dev;
1743                 pci_dev_put(pdev);
1744         }
1745
1746         memset(&props, 0, sizeof(struct backlight_properties));
1747         props.type = BACKLIGHT_FIRMWARE;
1748         props.max_brightness =
1749                 device->brightness->count - ACPI_VIDEO_FIRST_LEVEL - 1;
1750         device->backlight = backlight_device_register(name,
1751                                                       parent,
1752                                                       device,
1753                                                       &acpi_backlight_ops,
1754                                                       &props);
1755         kfree(name);
1756         if (IS_ERR(device->backlight)) {
1757                 device->backlight = NULL;
1758                 return;
1759         }
1760
1761         /*
1762          * Save current brightness level in case we have to restore it
1763          * before acpi_video_device_lcd_set_level() is called next time.
1764          */
1765         device->backlight->props.brightness =
1766                         acpi_video_get_brightness(device->backlight);
1767
1768         device->cooling_dev = thermal_cooling_device_register("LCD",
1769                                 device->dev, &video_cooling_ops);
1770         if (IS_ERR(device->cooling_dev)) {
1771                 /*
1772                  * Set cooling_dev to NULL so we don't crash trying to free it.
1773                  * Also, why the hell we are returning early and not attempt to
1774                  * register video output if cooling device registration failed?
1775                  * -- dtor
1776                  */
1777                 device->cooling_dev = NULL;
1778                 return;
1779         }
1780
1781         dev_info(&device->dev->dev, "registered as cooling_device%d\n",
1782                  device->cooling_dev->id);
1783         result = sysfs_create_link(&device->dev->dev.kobj,
1784                         &device->cooling_dev->device.kobj,
1785                         "thermal_cooling");
1786         if (result)
1787                 printk(KERN_ERR PREFIX "Create sysfs link\n");
1788         result = sysfs_create_link(&device->cooling_dev->device.kobj,
1789                         &device->dev->dev.kobj, "device");
1790         if (result)
1791                 printk(KERN_ERR PREFIX "Create sysfs link\n");
1792 }
1793
1794 static void acpi_video_run_bcl_for_osi(struct acpi_video_bus *video)
1795 {
1796         struct acpi_video_device *dev;
1797         union acpi_object *levels;
1798
1799         mutex_lock(&video->device_list_lock);
1800         list_for_each_entry(dev, &video->video_device_list, entry) {
1801                 if (!acpi_video_device_lcd_query_levels(dev->dev->handle, &levels))
1802                         kfree(levels);
1803         }
1804         mutex_unlock(&video->device_list_lock);
1805 }
1806
1807 static bool acpi_video_should_register_backlight(struct acpi_video_device *dev)
1808 {
1809         /*
1810          * Do not create backlight device for video output
1811          * device that is not in the enumerated list.
1812          */
1813         if (!acpi_video_device_in_dod(dev)) {
1814                 dev_dbg(&dev->dev->dev, "not in _DOD list, ignore\n");
1815                 return false;
1816         }
1817
1818         if (only_lcd)
1819                 return dev->flags.lcd;
1820         return true;
1821 }
1822
1823 static int acpi_video_bus_register_backlight(struct acpi_video_bus *video)
1824 {
1825         struct acpi_video_device *dev;
1826
1827         if (video->backlight_registered)
1828                 return 0;
1829
1830         acpi_video_run_bcl_for_osi(video);
1831
1832         if (acpi_video_get_backlight_type() != acpi_backlight_video)
1833                 return 0;
1834
1835         mutex_lock(&video->device_list_lock);
1836         list_for_each_entry(dev, &video->video_device_list, entry) {
1837                 if (acpi_video_should_register_backlight(dev))
1838                         acpi_video_dev_register_backlight(dev);
1839         }
1840         mutex_unlock(&video->device_list_lock);
1841
1842         video->backlight_registered = true;
1843
1844         video->pm_nb.notifier_call = acpi_video_resume;
1845         video->pm_nb.priority = 0;
1846         return register_pm_notifier(&video->pm_nb);
1847 }
1848
1849 static void acpi_video_dev_unregister_backlight(struct acpi_video_device *device)
1850 {
1851         if (device->backlight) {
1852                 backlight_device_unregister(device->backlight);
1853                 device->backlight = NULL;
1854         }
1855         if (device->brightness) {
1856                 kfree(device->brightness->levels);
1857                 kfree(device->brightness);
1858                 device->brightness = NULL;
1859         }
1860         if (device->cooling_dev) {
1861                 sysfs_remove_link(&device->dev->dev.kobj, "thermal_cooling");
1862                 sysfs_remove_link(&device->cooling_dev->device.kobj, "device");
1863                 thermal_cooling_device_unregister(device->cooling_dev);
1864                 device->cooling_dev = NULL;
1865         }
1866 }
1867
1868 static int acpi_video_bus_unregister_backlight(struct acpi_video_bus *video)
1869 {
1870         struct acpi_video_device *dev;
1871         int error;
1872
1873         if (!video->backlight_registered)
1874                 return 0;
1875
1876         error = unregister_pm_notifier(&video->pm_nb);
1877
1878         mutex_lock(&video->device_list_lock);
1879         list_for_each_entry(dev, &video->video_device_list, entry)
1880                 acpi_video_dev_unregister_backlight(dev);
1881         mutex_unlock(&video->device_list_lock);
1882
1883         video->backlight_registered = false;
1884
1885         return error;
1886 }
1887
1888 static void acpi_video_dev_add_notify_handler(struct acpi_video_device *device)
1889 {
1890         acpi_status status;
1891         struct acpi_device *adev = device->dev;
1892
1893         status = acpi_install_notify_handler(adev->handle, ACPI_DEVICE_NOTIFY,
1894                                              acpi_video_device_notify, device);
1895         if (ACPI_FAILURE(status))
1896                 dev_err(&adev->dev, "Error installing notify handler\n");
1897         else
1898                 device->flags.notify = 1;
1899 }
1900
1901 static int acpi_video_bus_add_notify_handler(struct acpi_video_bus *video)
1902 {
1903         struct input_dev *input;
1904         struct acpi_video_device *dev;
1905         int error;
1906
1907         video->input = input = input_allocate_device();
1908         if (!input) {
1909                 error = -ENOMEM;
1910                 goto out;
1911         }
1912
1913         error = acpi_video_bus_start_devices(video);
1914         if (error)
1915                 goto err_free_input;
1916
1917         snprintf(video->phys, sizeof(video->phys),
1918                         "%s/video/input0", acpi_device_hid(video->device));
1919
1920         input->name = acpi_device_name(video->device);
1921         input->phys = video->phys;
1922         input->id.bustype = BUS_HOST;
1923         input->id.product = 0x06;
1924         input->dev.parent = &video->device->dev;
1925         input->evbit[0] = BIT(EV_KEY);
1926         set_bit(KEY_SWITCHVIDEOMODE, input->keybit);
1927         set_bit(KEY_VIDEO_NEXT, input->keybit);
1928         set_bit(KEY_VIDEO_PREV, input->keybit);
1929         set_bit(KEY_BRIGHTNESS_CYCLE, input->keybit);
1930         set_bit(KEY_BRIGHTNESSUP, input->keybit);
1931         set_bit(KEY_BRIGHTNESSDOWN, input->keybit);
1932         set_bit(KEY_BRIGHTNESS_ZERO, input->keybit);
1933         set_bit(KEY_DISPLAY_OFF, input->keybit);
1934
1935         error = input_register_device(input);
1936         if (error)
1937                 goto err_stop_dev;
1938
1939         mutex_lock(&video->device_list_lock);
1940         list_for_each_entry(dev, &video->video_device_list, entry)
1941                 acpi_video_dev_add_notify_handler(dev);
1942         mutex_unlock(&video->device_list_lock);
1943
1944         return 0;
1945
1946 err_stop_dev:
1947         acpi_video_bus_stop_devices(video);
1948 err_free_input:
1949         input_free_device(input);
1950         video->input = NULL;
1951 out:
1952         return error;
1953 }
1954
1955 static void acpi_video_dev_remove_notify_handler(struct acpi_video_device *dev)
1956 {
1957         if (dev->flags.notify) {
1958                 acpi_remove_notify_handler(dev->dev->handle, ACPI_DEVICE_NOTIFY,
1959                                            acpi_video_device_notify);
1960                 dev->flags.notify = 0;
1961         }
1962 }
1963
1964 static void acpi_video_bus_remove_notify_handler(struct acpi_video_bus *video)
1965 {
1966         struct acpi_video_device *dev;
1967
1968         mutex_lock(&video->device_list_lock);
1969         list_for_each_entry(dev, &video->video_device_list, entry)
1970                 acpi_video_dev_remove_notify_handler(dev);
1971         mutex_unlock(&video->device_list_lock);
1972
1973         acpi_video_bus_stop_devices(video);
1974         input_unregister_device(video->input);
1975         video->input = NULL;
1976 }
1977
1978 static int acpi_video_bus_put_devices(struct acpi_video_bus *video)
1979 {
1980         struct acpi_video_device *dev, *next;
1981
1982         mutex_lock(&video->device_list_lock);
1983         list_for_each_entry_safe(dev, next, &video->video_device_list, entry) {
1984                 list_del(&dev->entry);
1985                 kfree(dev);
1986         }
1987         mutex_unlock(&video->device_list_lock);
1988
1989         return 0;
1990 }
1991
1992 static int instance;
1993
1994 static int acpi_video_bus_add(struct acpi_device *device)
1995 {
1996         struct acpi_video_bus *video;
1997         int error;
1998         acpi_status status;
1999
2000         status = acpi_walk_namespace(ACPI_TYPE_DEVICE,
2001                                 device->parent->handle, 1,
2002                                 acpi_video_bus_match, NULL,
2003                                 device, NULL);
2004         if (status == AE_ALREADY_EXISTS) {
2005                 printk(KERN_WARNING FW_BUG
2006                         "Duplicate ACPI video bus devices for the"
2007                         " same VGA controller, please try module "
2008                         "parameter \"video.allow_duplicates=1\""
2009                         "if the current driver doesn't work.\n");
2010                 if (!allow_duplicates)
2011                         return -ENODEV;
2012         }
2013
2014         video = kzalloc(sizeof(struct acpi_video_bus), GFP_KERNEL);
2015         if (!video)
2016                 return -ENOMEM;
2017
2018         /* a hack to fix the duplicate name "VID" problem on T61 */
2019         if (!strcmp(device->pnp.bus_id, "VID")) {
2020                 if (instance)
2021                         device->pnp.bus_id[3] = '0' + instance;
2022                 instance++;
2023         }
2024         /* a hack to fix the duplicate name "VGA" problem on Pa 3553 */
2025         if (!strcmp(device->pnp.bus_id, "VGA")) {
2026                 if (instance)
2027                         device->pnp.bus_id[3] = '0' + instance;
2028                 instance++;
2029         }
2030
2031         video->device = device;
2032         strcpy(acpi_device_name(device), ACPI_VIDEO_BUS_NAME);
2033         strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
2034         device->driver_data = video;
2035
2036         acpi_video_bus_find_cap(video);
2037         error = acpi_video_bus_check(video);
2038         if (error)
2039                 goto err_free_video;
2040
2041         mutex_init(&video->device_list_lock);
2042         INIT_LIST_HEAD(&video->video_device_list);
2043
2044         error = acpi_video_bus_get_devices(video, device);
2045         if (error)
2046                 goto err_put_video;
2047
2048         printk(KERN_INFO PREFIX "%s [%s] (multi-head: %s  rom: %s  post: %s)\n",
2049                ACPI_VIDEO_DEVICE_NAME, acpi_device_bid(device),
2050                video->flags.multihead ? "yes" : "no",
2051                video->flags.rom ? "yes" : "no",
2052                video->flags.post ? "yes" : "no");
2053         mutex_lock(&video_list_lock);
2054         list_add_tail(&video->entry, &video_bus_head);
2055         mutex_unlock(&video_list_lock);
2056
2057         acpi_video_bus_register_backlight(video);
2058         acpi_video_bus_add_notify_handler(video);
2059
2060         return 0;
2061
2062 err_put_video:
2063         acpi_video_bus_put_devices(video);
2064         kfree(video->attached_array);
2065 err_free_video:
2066         kfree(video);
2067         device->driver_data = NULL;
2068
2069         return error;
2070 }
2071
2072 static int acpi_video_bus_remove(struct acpi_device *device)
2073 {
2074         struct acpi_video_bus *video = NULL;
2075
2076
2077         if (!device || !acpi_driver_data(device))
2078                 return -EINVAL;
2079
2080         video = acpi_driver_data(device);
2081
2082         acpi_video_bus_remove_notify_handler(video);
2083         acpi_video_bus_unregister_backlight(video);
2084         acpi_video_bus_put_devices(video);
2085
2086         mutex_lock(&video_list_lock);
2087         list_del(&video->entry);
2088         mutex_unlock(&video_list_lock);
2089
2090         kfree(video->attached_array);
2091         kfree(video);
2092
2093         return 0;
2094 }
2095
2096 static int __init is_i740(struct pci_dev *dev)
2097 {
2098         if (dev->device == 0x00D1)
2099                 return 1;
2100         if (dev->device == 0x7000)
2101                 return 1;
2102         return 0;
2103 }
2104
2105 static int __init intel_opregion_present(void)
2106 {
2107         int opregion = 0;
2108         struct pci_dev *dev = NULL;
2109         u32 address;
2110
2111         for_each_pci_dev(dev) {
2112                 if ((dev->class >> 8) != PCI_CLASS_DISPLAY_VGA)
2113                         continue;
2114                 if (dev->vendor != PCI_VENDOR_ID_INTEL)
2115                         continue;
2116                 /* We don't want to poke around undefined i740 registers */
2117                 if (is_i740(dev))
2118                         continue;
2119                 pci_read_config_dword(dev, 0xfc, &address);
2120                 if (!address)
2121                         continue;
2122                 opregion = 1;
2123         }
2124         return opregion;
2125 }
2126
2127 /* Check if the chassis-type indicates there is no builtin LCD panel */
2128 static bool dmi_is_desktop(void)
2129 {
2130         const char *chassis_type;
2131         unsigned long type;
2132
2133         chassis_type = dmi_get_system_info(DMI_CHASSIS_TYPE);
2134         if (!chassis_type)
2135                 return false;
2136
2137         if (kstrtoul(chassis_type, 10, &type) != 0)
2138                 return false;
2139
2140         switch (type) {
2141         case 0x03: /* Desktop */
2142         case 0x04: /* Low Profile Desktop */
2143         case 0x05: /* Pizza Box */
2144         case 0x06: /* Mini Tower */
2145         case 0x07: /* Tower */
2146         case 0x11: /* Main Server Chassis */
2147                 return true;
2148         }
2149
2150         return false;
2151 }
2152
2153 int acpi_video_register(void)
2154 {
2155         int ret = 0;
2156
2157         mutex_lock(&register_count_mutex);
2158         if (register_count) {
2159                 /*
2160                  * if the function of acpi_video_register is already called,
2161                  * don't register the acpi_vide_bus again and return no error.
2162                  */
2163                 goto leave;
2164         }
2165
2166         /*
2167          * We're seeing a lot of bogus backlight interfaces on newer machines
2168          * without a LCD such as desktops, servers and HDMI sticks. Checking
2169          * the lcd flag fixes this, so enable this on any machines which are
2170          * win8 ready (where we also prefer the native backlight driver, so
2171          * normally the acpi_video code should not register there anyways).
2172          */
2173         if (only_lcd == -1) {
2174                 if (dmi_is_desktop() && acpi_osi_is_win8())
2175                         only_lcd = true;
2176                 else
2177                         only_lcd = false;
2178         }
2179
2180         dmi_check_system(video_dmi_table);
2181
2182         ret = acpi_bus_register_driver(&acpi_video_bus);
2183         if (ret)
2184                 goto leave;
2185
2186         /*
2187          * When the acpi_video_bus is loaded successfully, increase
2188          * the counter reference.
2189          */
2190         register_count = 1;
2191
2192 leave:
2193         mutex_unlock(&register_count_mutex);
2194         return ret;
2195 }
2196 EXPORT_SYMBOL(acpi_video_register);
2197
2198 void acpi_video_unregister(void)
2199 {
2200         mutex_lock(&register_count_mutex);
2201         if (register_count) {
2202                 acpi_bus_unregister_driver(&acpi_video_bus);
2203                 register_count = 0;
2204         }
2205         mutex_unlock(&register_count_mutex);
2206 }
2207 EXPORT_SYMBOL(acpi_video_unregister);
2208
2209 void acpi_video_unregister_backlight(void)
2210 {
2211         struct acpi_video_bus *video;
2212
2213         mutex_lock(&register_count_mutex);
2214         if (register_count) {
2215                 mutex_lock(&video_list_lock);
2216                 list_for_each_entry(video, &video_bus_head, entry)
2217                         acpi_video_bus_unregister_backlight(video);
2218                 mutex_unlock(&video_list_lock);
2219         }
2220         mutex_unlock(&register_count_mutex);
2221 }
2222
2223 bool acpi_video_handles_brightness_key_presses(void)
2224 {
2225         bool have_video_busses;
2226
2227         mutex_lock(&video_list_lock);
2228         have_video_busses = !list_empty(&video_bus_head);
2229         mutex_unlock(&video_list_lock);
2230
2231         return have_video_busses &&
2232                (report_key_events & REPORT_BRIGHTNESS_KEY_EVENTS);
2233 }
2234 EXPORT_SYMBOL(acpi_video_handles_brightness_key_presses);
2235
2236 /*
2237  * This is kind of nasty. Hardware using Intel chipsets may require
2238  * the video opregion code to be run first in order to initialise
2239  * state before any ACPI video calls are made. To handle this we defer
2240  * registration of the video class until the opregion code has run.
2241  */
2242
2243 static int __init acpi_video_init(void)
2244 {
2245         /*
2246          * Let the module load even if ACPI is disabled (e.g. due to
2247          * a broken BIOS) so that i915.ko can still be loaded on such
2248          * old systems without an AcpiOpRegion.
2249          *
2250          * acpi_video_register() will report -ENODEV later as well due
2251          * to acpi_disabled when i915.ko tries to register itself afterwards.
2252          */
2253         if (acpi_disabled)
2254                 return 0;
2255
2256         if (intel_opregion_present())
2257                 return 0;
2258
2259         return acpi_video_register();
2260 }
2261
2262 static void __exit acpi_video_exit(void)
2263 {
2264         acpi_video_detect_exit();
2265         acpi_video_unregister();
2266
2267         return;
2268 }
2269
2270 module_init(acpi_video_init);
2271 module_exit(acpi_video_exit);