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ACPI / video: Add 4 new models to the use_native_backlight DMI list
[linux-2.6/btrfs-unstable.git] / drivers / acpi / video.c
blob101fb090dcb9d59632979db199483d4d46babc57
1 /*
2 * video.c - ACPI Video Driver
3 *
4 * Copyright (C) 2004 Luming Yu <luming.yu@intel.com>
5 * Copyright (C) 2004 Bruno Ducrot <ducrot@poupinou.org>
6 * Copyright (C) 2006 Thomas Tuttle <linux-kernel@ttuttle.net>
7 *
8 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or (at
13 * your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful, but
16 * WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License along
21 * with this program; if not, write to the Free Software Foundation, Inc.,
22 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
23 *
24 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
25 */
26
27 #include <linux/kernel.h>
28 #include <linux/module.h>
29 #include <linux/init.h>
30 #include <linux/types.h>
31 #include <linux/list.h>
32 #include <linux/mutex.h>
33 #include <linux/input.h>
34 #include <linux/backlight.h>
35 #include <linux/thermal.h>
36 #include <linux/sort.h>
37 #include <linux/pci.h>
38 #include <linux/pci_ids.h>
39 #include <linux/slab.h>
40 #include <linux/dmi.h>
41 #include <linux/suspend.h>
42 #include <linux/acpi.h>
43 #include <acpi/video.h>
44 #include <asm/uaccess.h>
45
46 #include "internal.h"
47
48 #define ACPI_VIDEO_BUS_NAME "Video Bus"
49 #define ACPI_VIDEO_DEVICE_NAME "Video Device"
50 #define ACPI_VIDEO_NOTIFY_SWITCH 0x80
51 #define ACPI_VIDEO_NOTIFY_PROBE 0x81
52 #define ACPI_VIDEO_NOTIFY_CYCLE 0x82
53 #define ACPI_VIDEO_NOTIFY_NEXT_OUTPUT 0x83
54 #define ACPI_VIDEO_NOTIFY_PREV_OUTPUT 0x84
55
56 #define ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS 0x85
57 #define ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS 0x86
58 #define ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS 0x87
59 #define ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS 0x88
60 #define ACPI_VIDEO_NOTIFY_DISPLAY_OFF 0x89
61
62 #define MAX_NAME_LEN 20
63
64 #define _COMPONENT ACPI_VIDEO_COMPONENT
65 ACPI_MODULE_NAME("video");
66
67 MODULE_AUTHOR("Bruno Ducrot");
68 MODULE_DESCRIPTION("ACPI Video Driver");
69 MODULE_LICENSE("GPL");
70
71 static bool brightness_switch_enabled;
72 module_param(brightness_switch_enabled, bool, 0644);
73
74 /*
75 * By default, we don't allow duplicate ACPI video bus devices
76 * under the same VGA controller
77 */
78 static bool allow_duplicates;
79 module_param(allow_duplicates, bool, 0644);
80
81 /*
82 * For Windows 8 systems: used to decide if video module
83 * should skip registering backlight interface of its own.
84 */
85 static int use_native_backlight_param = -1;
86 module_param_named(use_native_backlight, use_native_backlight_param, int, 0444);
87 static bool use_native_backlight_dmi = false;
88
89 static int register_count;
90 static struct mutex video_list_lock;
91 static struct list_head video_bus_head;
92 static int acpi_video_bus_add(struct acpi_device *device);
93 static int acpi_video_bus_remove(struct acpi_device *device);
94 static void acpi_video_bus_notify(struct acpi_device *device, u32 event);
95
96 static const struct acpi_device_id video_device_ids[] = {
97 {ACPI_VIDEO_HID, 0},
98 {"", 0},
99 };
100 MODULE_DEVICE_TABLE(acpi, video_device_ids);
101
102 static struct acpi_driver acpi_video_bus = {
103 .name = "video",
104 .class = ACPI_VIDEO_CLASS,
105 .ids = video_device_ids,
106 .ops = {
107 .add = acpi_video_bus_add,
108 .remove = acpi_video_bus_remove,
109 .notify = acpi_video_bus_notify,
110 },
111 };
112
113 struct acpi_video_bus_flags {
114 u8 multihead:1; /* can switch video heads */
115 u8 rom:1; /* can retrieve a video rom */
116 u8 post:1; /* can configure the head to */
117 u8 reserved:5;
118 };
119
120 struct acpi_video_bus_cap {
121 u8 _DOS:1; /* Enable/Disable output switching */
122 u8 _DOD:1; /* Enumerate all devices attached to display adapter */
123 u8 _ROM:1; /* Get ROM Data */
124 u8 _GPD:1; /* Get POST Device */
125 u8 _SPD:1; /* Set POST Device */
126 u8 _VPO:1; /* Video POST Options */
127 u8 reserved:2;
128 };
129
130 struct acpi_video_device_attrib {
131 u32 display_index:4; /* A zero-based instance of the Display */
132 u32 display_port_attachment:4; /* This field differentiates the display type */
133 u32 display_type:4; /* Describe the specific type in use */
134 u32 vendor_specific:4; /* Chipset Vendor Specific */
135 u32 bios_can_detect:1; /* BIOS can detect the device */
136 u32 depend_on_vga:1; /* Non-VGA output device whose power is related to
137 the VGA device. */
138 u32 pipe_id:3; /* For VGA multiple-head devices. */
139 u32 reserved:10; /* Must be 0 */
140 u32 device_id_scheme:1; /* Device ID Scheme */
141 };
142
143 struct acpi_video_enumerated_device {
144 union {
145 u32 int_val;
146 struct acpi_video_device_attrib attrib;
147 } value;
148 struct acpi_video_device *bind_info;
149 };
150
151 struct acpi_video_bus {
152 struct acpi_device *device;
153 bool backlight_registered;
154 bool backlight_notifier_registered;
155 u8 dos_setting;
156 struct acpi_video_enumerated_device *attached_array;
157 u8 attached_count;
158 struct acpi_video_bus_cap cap;
159 struct acpi_video_bus_flags flags;
160 struct list_head video_device_list;
161 struct mutex device_list_lock; /* protects video_device_list */
162 struct list_head entry;
163 struct input_dev *input;
164 char phys[32]; /* for input device */
165 struct notifier_block pm_nb;
166 struct notifier_block backlight_nb;
167 };
168
169 struct acpi_video_device_flags {
170 u8 crt:1;
171 u8 lcd:1;
172 u8 tvout:1;
173 u8 dvi:1;
174 u8 bios:1;
175 u8 unknown:1;
176 u8 notify:1;
177 u8 reserved:1;
178 };
179
180 struct acpi_video_device_cap {
181 u8 _ADR:1; /* Return the unique ID */
182 u8 _BCL:1; /* Query list of brightness control levels supported */
183 u8 _BCM:1; /* Set the brightness level */
184 u8 _BQC:1; /* Get current brightness level */
185 u8 _BCQ:1; /* Some buggy BIOS uses _BCQ instead of _BQC */
186 u8 _DDC:1; /* Return the EDID for this device */
187 };
188
189 struct acpi_video_brightness_flags {
190 u8 _BCL_no_ac_battery_levels:1; /* no AC/Battery levels in _BCL */
191 u8 _BCL_reversed:1; /* _BCL package is in a reversed order */
192 u8 _BQC_use_index:1; /* _BQC returns an index value */
193 };
194
195 struct acpi_video_device_brightness {
196 int curr;
197 int count;
198 int *levels;
199 struct acpi_video_brightness_flags flags;
200 };
201
202 struct acpi_video_device {
203 unsigned long device_id;
204 struct acpi_video_device_flags flags;
205 struct acpi_video_device_cap cap;
206 struct list_head entry;
207 struct acpi_video_bus *video;
208 struct acpi_device *dev;
209 struct acpi_video_device_brightness *brightness;
210 struct backlight_device *backlight;
211 struct thermal_cooling_device *cooling_dev;
212 };
213
214 static const char device_decode[][30] = {
215 "motherboard VGA device",
216 "PCI VGA device",
217 "AGP VGA device",
218 "UNKNOWN",
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 int acpi_video_switch_brightness(struct acpi_video_device *device,
234 int event);
235
236 static bool acpi_video_use_native_backlight(void)
237 {
238 if (use_native_backlight_param != -1)
239 return use_native_backlight_param;
240 else
241 return use_native_backlight_dmi;
242 }
243
244 static bool acpi_video_verify_backlight_support(void)
245 {
246 if (acpi_osi_is_win8() && acpi_video_use_native_backlight() &&
247 backlight_device_registered(BACKLIGHT_RAW))
248 return false;
249 return acpi_video_backlight_support();
250 }
251
252 /* backlight device sysfs support */
253 static int acpi_video_get_brightness(struct backlight_device *bd)
254 {
255 unsigned long long cur_level;
256 int i;
257 struct acpi_video_device *vd = bl_get_data(bd);
258
259 if (acpi_video_device_lcd_get_level_current(vd, &cur_level, false))
260 return -EINVAL;
261 for (i = 2; i < vd->brightness->count; i++) {
262 if (vd->brightness->levels[i] == cur_level)
263 /*
264 * The first two entries are special - see page 575
265 * of the ACPI spec 3.0
266 */
267 return i - 2;
268 }
269 return 0;
270 }
271
272 static int acpi_video_set_brightness(struct backlight_device *bd)
273 {
274 int request_level = bd->props.brightness + 2;
275 struct acpi_video_device *vd = bl_get_data(bd);
276
277 return acpi_video_device_lcd_set_level(vd,
278 vd->brightness->levels[request_level]);
279 }
280
281 static const struct backlight_ops acpi_backlight_ops = {
282 .get_brightness = acpi_video_get_brightness,
283 .update_status = acpi_video_set_brightness,
284 };
285
286 /* thermal cooling device callbacks */
287 static int video_get_max_state(struct thermal_cooling_device *cooling_dev, unsigned
288 long *state)
289 {
290 struct acpi_device *device = cooling_dev->devdata;
291 struct acpi_video_device *video = acpi_driver_data(device);
292
293 *state = video->brightness->count - 3;
294 return 0;
295 }
296
297 static int video_get_cur_state(struct thermal_cooling_device *cooling_dev, unsigned
298 long *state)
299 {
300 struct acpi_device *device = cooling_dev->devdata;
301 struct acpi_video_device *video = acpi_driver_data(device);
302 unsigned long long level;
303 int offset;
304
305 if (acpi_video_device_lcd_get_level_current(video, &level, false))
306 return -EINVAL;
307 for (offset = 2; offset < video->brightness->count; offset++)
308 if (level == video->brightness->levels[offset]) {
309 *state = video->brightness->count - offset - 1;
310 return 0;
311 }
312
313 return -EINVAL;
314 }
315
316 static int
317 video_set_cur_state(struct thermal_cooling_device *cooling_dev, unsigned long state)
318 {
319 struct acpi_device *device = cooling_dev->devdata;
320 struct acpi_video_device *video = acpi_driver_data(device);
321 int level;
322
323 if (state >= video->brightness->count - 2)
324 return -EINVAL;
325
326 state = video->brightness->count - state;
327 level = video->brightness->levels[state - 1];
328 return acpi_video_device_lcd_set_level(video, level);
329 }
330
331 static const struct thermal_cooling_device_ops video_cooling_ops = {
332 .get_max_state = video_get_max_state,
333 .get_cur_state = video_get_cur_state,
334 .set_cur_state = video_set_cur_state,
335 };
336
337 /*
338 * --------------------------------------------------------------------------
339 * Video Management
340 * --------------------------------------------------------------------------
341 */
342
343 static int
344 acpi_video_device_lcd_query_levels(struct acpi_video_device *device,
345 union acpi_object **levels)
346 {
347 int status;
348 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
349 union acpi_object *obj;
350
351
352 *levels = NULL;
353
354 status = acpi_evaluate_object(device->dev->handle, "_BCL", NULL, &buffer);
355 if (!ACPI_SUCCESS(status))
356 return status;
357 obj = (union acpi_object *)buffer.pointer;
358 if (!obj || (obj->type != ACPI_TYPE_PACKAGE)) {
359 printk(KERN_ERR PREFIX "Invalid _BCL data\n");
360 status = -EFAULT;
361 goto err;
362 }
363
364 *levels = obj;
365
366 return 0;
367
368 err:
369 kfree(buffer.pointer);
370
371 return status;
372 }
373
374 static int
375 acpi_video_device_lcd_set_level(struct acpi_video_device *device, int level)
376 {
377 int status;
378 int state;
379
380 status = acpi_execute_simple_method(device->dev->handle,
381 "_BCM", level);
382 if (ACPI_FAILURE(status)) {
383 ACPI_ERROR((AE_INFO, "Evaluating _BCM failed"));
384 return -EIO;
385 }
386
387 device->brightness->curr = level;
388 for (state = 2; state < device->brightness->count; state++)
389 if (level == device->brightness->levels[state]) {
390 if (device->backlight)
391 device->backlight->props.brightness = state - 2;
392 return 0;
393 }
394
395 ACPI_ERROR((AE_INFO, "Current brightness invalid"));
396 return -EINVAL;
397 }
398
399 /*
400 * For some buggy _BQC methods, we need to add a constant value to
401 * the _BQC return value to get the actual current brightness level
402 */
403
404 static int bqc_offset_aml_bug_workaround;
405 static int __init video_set_bqc_offset(const struct dmi_system_id *d)
406 {
407 bqc_offset_aml_bug_workaround = 9;
408 return 0;
409 }
410
411 static int __init video_set_use_native_backlight(const struct dmi_system_id *d)
412 {
413 use_native_backlight_dmi = true;
414 return 0;
415 }
416
417 static struct dmi_system_id video_dmi_table[] __initdata = {
418 /*
419 * Broken _BQC workaround http://bugzilla.kernel.org/show_bug.cgi?id=13121
420 */
421 {
422 .callback = video_set_bqc_offset,
423 .ident = "Acer Aspire 5720",
424 .matches = {
425 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
426 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5720"),
427 },
428 },
429 {
430 .callback = video_set_bqc_offset,
431 .ident = "Acer Aspire 5710Z",
432 .matches = {
433 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
434 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5710Z"),
435 },
436 },
437 {
438 .callback = video_set_bqc_offset,
439 .ident = "eMachines E510",
440 .matches = {
441 DMI_MATCH(DMI_BOARD_VENDOR, "EMACHINES"),
442 DMI_MATCH(DMI_PRODUCT_NAME, "eMachines E510"),
443 },
444 },
445 {
446 .callback = video_set_bqc_offset,
447 .ident = "Acer Aspire 5315",
448 .matches = {
449 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
450 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5315"),
451 },
452 },
453 {
454 .callback = video_set_bqc_offset,
455 .ident = "Acer Aspire 7720",
456 .matches = {
457 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
458 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 7720"),
459 },
460 },
461 {
462 .callback = video_set_use_native_backlight,
463 .ident = "ThinkPad T430 and T430s",
464 .matches = {
465 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
466 DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T430"),
467 },
468 },
469 {
470 .callback = video_set_use_native_backlight,
471 .ident = "ThinkPad X230",
472 .matches = {
473 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
474 DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X230"),
475 },
476 },
477 {
478 .callback = video_set_use_native_backlight,
479 .ident = "ThinkPad W530",
480 .matches = {
481 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
482 DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad W530"),
483 },
484 },
485 {
486 .callback = video_set_use_native_backlight,
487 .ident = "ThinkPad X1 Carbon",
488 .matches = {
489 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
490 DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X1 Carbon"),
491 },
492 },
493 {
494 .callback = video_set_use_native_backlight,
495 .ident = "Lenovo Yoga 13",
496 .matches = {
497 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
498 DMI_MATCH(DMI_PRODUCT_VERSION, "Lenovo IdeaPad Yoga 13"),
499 },
500 },
501 {
502 .callback = video_set_use_native_backlight,
503 .ident = "Lenovo Yoga 2 11",
504 .matches = {
505 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
506 DMI_MATCH(DMI_PRODUCT_VERSION, "Lenovo Yoga 2 11"),
507 },
508 },
509 {
510 .callback = video_set_use_native_backlight,
511 .ident = "Thinkpad Helix",
512 .matches = {
513 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
514 DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad Helix"),
515 },
516 },
517 {
518 .callback = video_set_use_native_backlight,
519 .ident = "Dell Inspiron 7520",
520 .matches = {
521 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
522 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 7520"),
523 },
524 },
525 {
526 .callback = video_set_use_native_backlight,
527 .ident = "Acer Aspire 5733Z",
528 .matches = {
529 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
530 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5733Z"),
531 },
532 },
533 {
534 .callback = video_set_use_native_backlight,
535 .ident = "Acer Aspire 5742G",
536 .matches = {
537 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
538 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5742G"),
539 },
540 },
541 {
542 .callback = video_set_use_native_backlight,
543 .ident = "Acer Aspire V5-171",
544 .matches = {
545 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
546 DMI_MATCH(DMI_PRODUCT_NAME, "V5-171"),
547 },
548 },
549 {
550 .callback = video_set_use_native_backlight,
551 .ident = "Acer Aspire V5-431",
552 .matches = {
553 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
554 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire V5-431"),
555 },
556 },
557 {
558 .callback = video_set_use_native_backlight,
559 .ident = "Acer Aspire V5-471G",
560 .matches = {
561 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
562 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire V5-471G"),
563 },
564 },
565 {
566 .callback = video_set_use_native_backlight,
567 .ident = "HP ProBook 4340s",
568 .matches = {
569 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
570 DMI_MATCH(DMI_PRODUCT_VERSION, "HP ProBook 4340s"),
571 },
572 },
573 {
574 .callback = video_set_use_native_backlight,
575 .ident = "HP ProBook 2013 models",
576 .matches = {
577 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
578 DMI_MATCH(DMI_PRODUCT_NAME, "HP ProBook "),
579 DMI_MATCH(DMI_PRODUCT_NAME, " G1"),
580 },
581 },
582 {
583 .callback = video_set_use_native_backlight,
584 .ident = "HP EliteBook 2013 models",
585 .matches = {
586 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
587 DMI_MATCH(DMI_PRODUCT_NAME, "HP EliteBook "),
588 DMI_MATCH(DMI_PRODUCT_NAME, " G1"),
589 },
590 },
591 {
592 .callback = video_set_use_native_backlight,
593 .ident = "HP ZBook 14",
594 .matches = {
595 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
596 DMI_MATCH(DMI_PRODUCT_NAME, "HP ZBook 14"),
597 },
598 },
599 {
600 .callback = video_set_use_native_backlight,
601 .ident = "HP ZBook 15",
602 .matches = {
603 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
604 DMI_MATCH(DMI_PRODUCT_NAME, "HP ZBook 15"),
605 },
606 },
607 {
608 .callback = video_set_use_native_backlight,
609 .ident = "HP ZBook 17",
610 .matches = {
611 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
612 DMI_MATCH(DMI_PRODUCT_NAME, "HP ZBook 17"),
613 },
614 },
615 {
616 .callback = video_set_use_native_backlight,
617 .ident = "HP EliteBook 8470p",
618 .matches = {
619 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
620 DMI_MATCH(DMI_PRODUCT_NAME, "HP EliteBook 8470p"),
621 },
622 },
623 {
624 .callback = video_set_use_native_backlight,
625 .ident = "HP EliteBook 8780w",
626 .matches = {
627 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
628 DMI_MATCH(DMI_PRODUCT_NAME, "HP EliteBook 8780w"),
629 },
630 },
631 {}
632 };
633
634 static unsigned long long
635 acpi_video_bqc_value_to_level(struct acpi_video_device *device,
636 unsigned long long bqc_value)
637 {
638 unsigned long long level;
639
640 if (device->brightness->flags._BQC_use_index) {
641 /*
642 * _BQC returns an index that doesn't account for
643 * the first 2 items with special meaning, so we need
644 * to compensate for that by offsetting ourselves
645 */
646 if (device->brightness->flags._BCL_reversed)
647 bqc_value = device->brightness->count - 3 - bqc_value;
648
649 level = device->brightness->levels[bqc_value + 2];
650 } else {
651 level = bqc_value;
652 }
653
654 level += bqc_offset_aml_bug_workaround;
655
656 return level;
657 }
658
659 static int
660 acpi_video_device_lcd_get_level_current(struct acpi_video_device *device,
661 unsigned long long *level, bool raw)
662 {
663 acpi_status status = AE_OK;
664 int i;
665
666 if (device->cap._BQC || device->cap._BCQ) {
667 char *buf = device->cap._BQC ? "_BQC" : "_BCQ";
668
669 status = acpi_evaluate_integer(device->dev->handle, buf,
670 NULL, level);
671 if (ACPI_SUCCESS(status)) {
672 if (raw) {
673 /*
674 * Caller has indicated he wants the raw
675 * value returned by _BQC, so don't furtherly
676 * mess with the value.
677 */
678 return 0;
679 }
680
681 *level = acpi_video_bqc_value_to_level(device, *level);
682
683 for (i = 2; i < device->brightness->count; i++)
684 if (device->brightness->levels[i] == *level) {
685 device->brightness->curr = *level;
686 return 0;
687 }
688 /*
689 * BQC returned an invalid level.
690 * Stop using it.
691 */
692 ACPI_WARNING((AE_INFO,
693 "%s returned an invalid level",
694 buf));
695 device->cap._BQC = device->cap._BCQ = 0;
696 } else {
697 /*
698 * Fixme:
699 * should we return an error or ignore this failure?
700 * dev->brightness->curr is a cached value which stores
701 * the correct current backlight level in most cases.
702 * ACPI video backlight still works w/ buggy _BQC.
703 * http://bugzilla.kernel.org/show_bug.cgi?id=12233
704 */
705 ACPI_WARNING((AE_INFO, "Evaluating %s failed", buf));
706 device->cap._BQC = device->cap._BCQ = 0;
707 }
708 }
709
710 *level = device->brightness->curr;
711 return 0;
712 }
713
714 static int
715 acpi_video_device_EDID(struct acpi_video_device *device,
716 union acpi_object **edid, ssize_t length)
717 {
718 int status;
719 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
720 union acpi_object *obj;
721 union acpi_object arg0 = { ACPI_TYPE_INTEGER };
722 struct acpi_object_list args = { 1, &arg0 };
723
724
725 *edid = NULL;
726
727 if (!device)
728 return -ENODEV;
729 if (length == 128)
730 arg0.integer.value = 1;
731 else if (length == 256)
732 arg0.integer.value = 2;
733 else
734 return -EINVAL;
735
736 status = acpi_evaluate_object(device->dev->handle, "_DDC", &args, &buffer);
737 if (ACPI_FAILURE(status))
738 return -ENODEV;
739
740 obj = buffer.pointer;
741
742 if (obj && obj->type == ACPI_TYPE_BUFFER)
743 *edid = obj;
744 else {
745 printk(KERN_ERR PREFIX "Invalid _DDC data\n");
746 status = -EFAULT;
747 kfree(obj);
748 }
749
750 return status;
751 }
752
753 /* bus */
754
755 /*
756 * Arg:
757 * video : video bus device pointer
758 * bios_flag :
759 * 0. The system BIOS should NOT automatically switch(toggle)
760 * the active display output.
761 * 1. The system BIOS should automatically switch (toggle) the
762 * active display output. No switch event.
763 * 2. The _DGS value should be locked.
764 * 3. The system BIOS should not automatically switch (toggle) the
765 * active display output, but instead generate the display switch
766 * event notify code.
767 * lcd_flag :
768 * 0. The system BIOS should automatically control the brightness level
769 * of the LCD when the power changes from AC to DC
770 * 1. The system BIOS should NOT automatically control the brightness
771 * level of the LCD when the power changes from AC to DC.
772 * Return Value:
773 * -EINVAL wrong arg.
774 */
775
776 static int
777 acpi_video_bus_DOS(struct acpi_video_bus *video, int bios_flag, int lcd_flag)
778 {
779 acpi_status status;
780
781 if (!video->cap._DOS)
782 return 0;
783
784 if (bios_flag < 0 || bios_flag > 3 || lcd_flag < 0 || lcd_flag > 1)
785 return -EINVAL;
786 video->dos_setting = (lcd_flag << 2) | bios_flag;
787 status = acpi_execute_simple_method(video->device->handle, "_DOS",
788 (lcd_flag << 2) | bios_flag);
789 if (ACPI_FAILURE(status))
790 return -EIO;
791
792 return 0;
793 }
794
795 /*
796 * Simple comparison function used to sort backlight levels.
797 */
798
799 static int
800 acpi_video_cmp_level(const void *a, const void *b)
801 {
802 return *(int *)a - *(int *)b;
803 }
804
805 /*
806 * Decides if _BQC/_BCQ for this system is usable
807 *
808 * We do this by changing the level first and then read out the current
809 * brightness level, if the value does not match, find out if it is using
810 * index. If not, clear the _BQC/_BCQ capability.
811 */
812 static int acpi_video_bqc_quirk(struct acpi_video_device *device,
813 int max_level, int current_level)
814 {
815 struct acpi_video_device_brightness *br = device->brightness;
816 int result;
817 unsigned long long level;
818 int test_level;
819
820 /* don't mess with existing known broken systems */
821 if (bqc_offset_aml_bug_workaround)
822 return 0;
823
824 /*
825 * Some systems always report current brightness level as maximum
826 * through _BQC, we need to test another value for them.
827 */
828 test_level = current_level == max_level ? br->levels[3] : max_level;
829
830 result = acpi_video_device_lcd_set_level(device, test_level);
831 if (result)
832 return result;
833
834 result = acpi_video_device_lcd_get_level_current(device, &level, true);
835 if (result)
836 return result;
837
838 if (level != test_level) {
839 /* buggy _BQC found, need to find out if it uses index */
840 if (level < br->count) {
841 if (br->flags._BCL_reversed)
842 level = br->count - 3 - level;
843 if (br->levels[level + 2] == test_level)
844 br->flags._BQC_use_index = 1;
845 }
846
847 if (!br->flags._BQC_use_index)
848 device->cap._BQC = device->cap._BCQ = 0;
849 }
850
851 return 0;
852 }
853
854
855 /*
856 * Arg:
857 * device : video output device (LCD, CRT, ..)
858 *
859 * Return Value:
860 * Maximum brightness level
861 *
862 * Allocate and initialize device->brightness.
863 */
864
865 static int
866 acpi_video_init_brightness(struct acpi_video_device *device)
867 {
868 union acpi_object *obj = NULL;
869 int i, max_level = 0, count = 0, level_ac_battery = 0;
870 unsigned long long level, level_old;
871 union acpi_object *o;
872 struct acpi_video_device_brightness *br = NULL;
873 int result = -EINVAL;
874 u32 value;
875
876 if (!ACPI_SUCCESS(acpi_video_device_lcd_query_levels(device, &obj))) {
877 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Could not query available "
878 "LCD brightness level\n"));
879 goto out;
880 }
881
882 if (obj->package.count < 2)
883 goto out;
884
885 br = kzalloc(sizeof(*br), GFP_KERNEL);
886 if (!br) {
887 printk(KERN_ERR "can't allocate memory\n");
888 result = -ENOMEM;
889 goto out;
890 }
891
892 br->levels = kmalloc((obj->package.count + 2) * sizeof *(br->levels),
893 GFP_KERNEL);
894 if (!br->levels) {
895 result = -ENOMEM;
896 goto out_free;
897 }
898
899 for (i = 0; i < obj->package.count; i++) {
900 o = (union acpi_object *)&obj->package.elements[i];
901 if (o->type != ACPI_TYPE_INTEGER) {
902 printk(KERN_ERR PREFIX "Invalid data\n");
903 continue;
904 }
905 value = (u32) o->integer.value;
906 /* Skip duplicate entries */
907 if (count > 2 && br->levels[count - 1] == value)
908 continue;
909
910 br->levels[count] = value;
911
912 if (br->levels[count] > max_level)
913 max_level = br->levels[count];
914 count++;
915 }
916
917 /*
918 * some buggy BIOS don't export the levels
919 * when machine is on AC/Battery in _BCL package.
920 * In this case, the first two elements in _BCL packages
921 * are also supported brightness levels that OS should take care of.
922 */
923 for (i = 2; i < count; i++) {
924 if (br->levels[i] == br->levels[0])
925 level_ac_battery++;
926 if (br->levels[i] == br->levels[1])
927 level_ac_battery++;
928 }
929
930 if (level_ac_battery < 2) {
931 level_ac_battery = 2 - level_ac_battery;
932 br->flags._BCL_no_ac_battery_levels = 1;
933 for (i = (count - 1 + level_ac_battery); i >= 2; i--)
934 br->levels[i] = br->levels[i - level_ac_battery];
935 count += level_ac_battery;
936 } else if (level_ac_battery > 2)
937 ACPI_ERROR((AE_INFO, "Too many duplicates in _BCL package"));
938
939 /* Check if the _BCL package is in a reversed order */
940 if (max_level == br->levels[2]) {
941 br->flags._BCL_reversed = 1;
942 sort(&br->levels[2], count - 2, sizeof(br->levels[2]),
943 acpi_video_cmp_level, NULL);
944 } else if (max_level != br->levels[count - 1])
945 ACPI_ERROR((AE_INFO,
946 "Found unordered _BCL package"));
947
948 br->count = count;
949 device->brightness = br;
950
951 /* _BQC uses INDEX while _BCL uses VALUE in some laptops */
952 br->curr = level = max_level;
953
954 if (!device->cap._BQC)
955 goto set_level;
956
957 result = acpi_video_device_lcd_get_level_current(device,
958 &level_old, true);
959 if (result)
960 goto out_free_levels;
961
962 result = acpi_video_bqc_quirk(device, max_level, level_old);
963 if (result)
964 goto out_free_levels;
965 /*
966 * cap._BQC may get cleared due to _BQC is found to be broken
967 * in acpi_video_bqc_quirk, so check again here.
968 */
969 if (!device->cap._BQC)
970 goto set_level;
971
972 level = acpi_video_bqc_value_to_level(device, level_old);
973 /*
974 * On some buggy laptops, _BQC returns an uninitialized
975 * value when invoked for the first time, i.e.
976 * level_old is invalid (no matter whether it's a level
977 * or an index). Set the backlight to max_level in this case.
978 */
979 for (i = 2; i < br->count; i++)
980 if (level == br->levels[i])
981 break;
982 if (i == br->count || !level)
983 level = max_level;
984
985 set_level:
986 result = acpi_video_device_lcd_set_level(device, level);
987 if (result)
988 goto out_free_levels;
989
990 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
991 "found %d brightness levels\n", count - 2));
992 kfree(obj);
993 return result;
994
995 out_free_levels:
996 kfree(br->levels);
997 out_free:
998 kfree(br);
999 out:
1000 device->brightness = NULL;
1001 kfree(obj);
1002 return result;
1003 }
1004
1005 /*
1006 * Arg:
1007 * device : video output device (LCD, CRT, ..)
1008 *
1009 * Return Value:
1010 * None
1011 *
1012 * Find out all required AML methods defined under the output
1013 * device.
1014 */
1015
1016 static void acpi_video_device_find_cap(struct acpi_video_device *device)
1017 {
1018 if (acpi_has_method(device->dev->handle, "_ADR"))
1019 device->cap._ADR = 1;
1020 if (acpi_has_method(device->dev->handle, "_BCL"))
1021 device->cap._BCL = 1;
1022 if (acpi_has_method(device->dev->handle, "_BCM"))
1023 device->cap._BCM = 1;
1024 if (acpi_has_method(device->dev->handle, "_BQC")) {
1025 device->cap._BQC = 1;
1026 } else if (acpi_has_method(device->dev->handle, "_BCQ")) {
1027 printk(KERN_WARNING FW_BUG "_BCQ is used instead of _BQC\n");
1028 device->cap._BCQ = 1;
1029 }
1030
1031 if (acpi_has_method(device->dev->handle, "_DDC"))
1032 device->cap._DDC = 1;
1033 }
1034
1035 /*
1036 * Arg:
1037 * device : video output device (VGA)
1038 *
1039 * Return Value:
1040 * None
1041 *
1042 * Find out all required AML methods defined under the video bus device.
1043 */
1044
1045 static void acpi_video_bus_find_cap(struct acpi_video_bus *video)
1046 {
1047 if (acpi_has_method(video->device->handle, "_DOS"))
1048 video->cap._DOS = 1;
1049 if (acpi_has_method(video->device->handle, "_DOD"))
1050 video->cap._DOD = 1;
1051 if (acpi_has_method(video->device->handle, "_ROM"))
1052 video->cap._ROM = 1;
1053 if (acpi_has_method(video->device->handle, "_GPD"))
1054 video->cap._GPD = 1;
1055 if (acpi_has_method(video->device->handle, "_SPD"))
1056 video->cap._SPD = 1;
1057 if (acpi_has_method(video->device->handle, "_VPO"))
1058 video->cap._VPO = 1;
1059 }
1060
1061 /*
1062 * Check whether the video bus device has required AML method to
1063 * support the desired features
1064 */
1065
1066 static int acpi_video_bus_check(struct acpi_video_bus *video)
1067 {
1068 acpi_status status = -ENOENT;
1069 struct pci_dev *dev;
1070
1071 if (!video)
1072 return -EINVAL;
1073
1074 dev = acpi_get_pci_dev(video->device->handle);
1075 if (!dev)
1076 return -ENODEV;
1077 pci_dev_put(dev);
1078
1079 /*
1080 * Since there is no HID, CID and so on for VGA driver, we have
1081 * to check well known required nodes.
1082 */
1083
1084 /* Does this device support video switching? */
1085 if (video->cap._DOS || video->cap._DOD) {
1086 if (!video->cap._DOS) {
1087 printk(KERN_WARNING FW_BUG
1088 "ACPI(%s) defines _DOD but not _DOS\n",
1089 acpi_device_bid(video->device));
1090 }
1091 video->flags.multihead = 1;
1092 status = 0;
1093 }
1094
1095 /* Does this device support retrieving a video ROM? */
1096 if (video->cap._ROM) {
1097 video->flags.rom = 1;
1098 status = 0;
1099 }
1100
1101 /* Does this device support configuring which video device to POST? */
1102 if (video->cap._GPD && video->cap._SPD && video->cap._VPO) {
1103 video->flags.post = 1;
1104 status = 0;
1105 }
1106
1107 return status;
1108 }
1109
1110 /*
1111 * --------------------------------------------------------------------------
1112 * Driver Interface
1113 * --------------------------------------------------------------------------
1114 */
1115
1116 /* device interface */
1117 static struct acpi_video_device_attrib *
1118 acpi_video_get_device_attr(struct acpi_video_bus *video, unsigned long device_id)
1119 {
1120 struct acpi_video_enumerated_device *ids;
1121 int i;
1122
1123 for (i = 0; i < video->attached_count; i++) {
1124 ids = &video->attached_array[i];
1125 if ((ids->value.int_val & 0xffff) == device_id)
1126 return &ids->value.attrib;
1127 }
1128
1129 return NULL;
1130 }
1131
1132 static int
1133 acpi_video_get_device_type(struct acpi_video_bus *video,
1134 unsigned long device_id)
1135 {
1136 struct acpi_video_enumerated_device *ids;
1137 int i;
1138
1139 for (i = 0; i < video->attached_count; i++) {
1140 ids = &video->attached_array[i];
1141 if ((ids->value.int_val & 0xffff) == device_id)
1142 return ids->value.int_val;
1143 }
1144
1145 return 0;
1146 }
1147
1148 static int
1149 acpi_video_bus_get_one_device(struct acpi_device *device,
1150 struct acpi_video_bus *video)
1151 {
1152 unsigned long long device_id;
1153 int status, device_type;
1154 struct acpi_video_device *data;
1155 struct acpi_video_device_attrib *attribute;
1156
1157 status =
1158 acpi_evaluate_integer(device->handle, "_ADR", NULL, &device_id);
1159 /* Some device omits _ADR, we skip them instead of fail */
1160 if (ACPI_FAILURE(status))
1161 return 0;
1162
1163 data = kzalloc(sizeof(struct acpi_video_device), GFP_KERNEL);
1164 if (!data)
1165 return -ENOMEM;
1166
1167 strcpy(acpi_device_name(device), ACPI_VIDEO_DEVICE_NAME);
1168 strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
1169 device->driver_data = data;
1170
1171 data->device_id = device_id;
1172 data->video = video;
1173 data->dev = device;
1174
1175 attribute = acpi_video_get_device_attr(video, device_id);
1176
1177 if (attribute && attribute->device_id_scheme) {
1178 switch (attribute->display_type) {
1179 case ACPI_VIDEO_DISPLAY_CRT:
1180 data->flags.crt = 1;
1181 break;
1182 case ACPI_VIDEO_DISPLAY_TV:
1183 data->flags.tvout = 1;
1184 break;
1185 case ACPI_VIDEO_DISPLAY_DVI:
1186 data->flags.dvi = 1;
1187 break;
1188 case ACPI_VIDEO_DISPLAY_LCD:
1189 data->flags.lcd = 1;
1190 break;
1191 default:
1192 data->flags.unknown = 1;
1193 break;
1194 }
1195 if (attribute->bios_can_detect)
1196 data->flags.bios = 1;
1197 } else {
1198 /* Check for legacy IDs */
1199 device_type = acpi_video_get_device_type(video, device_id);
1200 /* Ignore bits 16 and 18-20 */
1201 switch (device_type & 0xffe2ffff) {
1202 case ACPI_VIDEO_DISPLAY_LEGACY_MONITOR:
1203 data->flags.crt = 1;
1204 break;
1205 case ACPI_VIDEO_DISPLAY_LEGACY_PANEL:
1206 data->flags.lcd = 1;
1207 break;
1208 case ACPI_VIDEO_DISPLAY_LEGACY_TV:
1209 data->flags.tvout = 1;
1210 break;
1211 default:
1212 data->flags.unknown = 1;
1213 }
1214 }
1215
1216 acpi_video_device_bind(video, data);
1217 acpi_video_device_find_cap(data);
1218
1219 mutex_lock(&video->device_list_lock);
1220 list_add_tail(&data->entry, &video->video_device_list);
1221 mutex_unlock(&video->device_list_lock);
1222
1223 return status;
1224 }
1225
1226 /*
1227 * Arg:
1228 * video : video bus device
1229 *
1230 * Return:
1231 * none
1232 *
1233 * Enumerate the video device list of the video bus,
1234 * bind the ids with the corresponding video devices
1235 * under the video bus.
1236 */
1237
1238 static void acpi_video_device_rebind(struct acpi_video_bus *video)
1239 {
1240 struct acpi_video_device *dev;
1241
1242 mutex_lock(&video->device_list_lock);
1243
1244 list_for_each_entry(dev, &video->video_device_list, entry)
1245 acpi_video_device_bind(video, dev);
1246
1247 mutex_unlock(&video->device_list_lock);
1248 }
1249
1250 /*
1251 * Arg:
1252 * video : video bus device
1253 * device : video output device under the video
1254 * bus
1255 *
1256 * Return:
1257 * none
1258 *
1259 * Bind the ids with the corresponding video devices
1260 * under the video bus.
1261 */
1262
1263 static void
1264 acpi_video_device_bind(struct acpi_video_bus *video,
1265 struct acpi_video_device *device)
1266 {
1267 struct acpi_video_enumerated_device *ids;
1268 int i;
1269
1270 for (i = 0; i < video->attached_count; i++) {
1271 ids = &video->attached_array[i];
1272 if (device->device_id == (ids->value.int_val & 0xffff)) {
1273 ids->bind_info = device;
1274 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "device_bind %d\n", i));
1275 }
1276 }
1277 }
1278
1279 /*
1280 * Arg:
1281 * video : video bus device
1282 *
1283 * Return:
1284 * < 0 : error
1285 *
1286 * Call _DOD to enumerate all devices attached to display adapter
1287 *
1288 */
1289
1290 static int acpi_video_device_enumerate(struct acpi_video_bus *video)
1291 {
1292 int status;
1293 int count;
1294 int i;
1295 struct acpi_video_enumerated_device *active_list;
1296 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1297 union acpi_object *dod = NULL;
1298 union acpi_object *obj;
1299
1300 status = acpi_evaluate_object(video->device->handle, "_DOD", NULL, &buffer);
1301 if (!ACPI_SUCCESS(status)) {
1302 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _DOD"));
1303 return status;
1304 }
1305
1306 dod = buffer.pointer;
1307 if (!dod || (dod->type != ACPI_TYPE_PACKAGE)) {
1308 ACPI_EXCEPTION((AE_INFO, status, "Invalid _DOD data"));
1309 status = -EFAULT;
1310 goto out;
1311 }
1312
1313 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d video heads in _DOD\n",
1314 dod->package.count));
1315
1316 active_list = kcalloc(1 + dod->package.count,
1317 sizeof(struct acpi_video_enumerated_device),
1318 GFP_KERNEL);
1319 if (!active_list) {
1320 status = -ENOMEM;
1321 goto out;
1322 }
1323
1324 count = 0;
1325 for (i = 0; i < dod->package.count; i++) {
1326 obj = &dod->package.elements[i];
1327
1328 if (obj->type != ACPI_TYPE_INTEGER) {
1329 printk(KERN_ERR PREFIX
1330 "Invalid _DOD data in element %d\n", i);
1331 continue;
1332 }
1333
1334 active_list[count].value.int_val = obj->integer.value;
1335 active_list[count].bind_info = NULL;
1336 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "dod element[%d] = %d\n", i,
1337 (int)obj->integer.value));
1338 count++;
1339 }
1340
1341 kfree(video->attached_array);
1342
1343 video->attached_array = active_list;
1344 video->attached_count = count;
1345
1346 out:
1347 kfree(buffer.pointer);
1348 return status;
1349 }
1350
1351 static int
1352 acpi_video_get_next_level(struct acpi_video_device *device,
1353 u32 level_current, u32 event)
1354 {
1355 int min, max, min_above, max_below, i, l, delta = 255;
1356 max = max_below = 0;
1357 min = min_above = 255;
1358 /* Find closest level to level_current */
1359 for (i = 2; i < device->brightness->count; i++) {
1360 l = device->brightness->levels[i];
1361 if (abs(l - level_current) < abs(delta)) {
1362 delta = l - level_current;
1363 if (!delta)
1364 break;
1365 }
1366 }
1367 /* Ajust level_current to closest available level */
1368 level_current += delta;
1369 for (i = 2; i < device->brightness->count; i++) {
1370 l = device->brightness->levels[i];
1371 if (l < min)
1372 min = l;
1373 if (l > max)
1374 max = l;
1375 if (l < min_above && l > level_current)
1376 min_above = l;
1377 if (l > max_below && l < level_current)
1378 max_below = l;
1379 }
1380
1381 switch (event) {
1382 case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:
1383 return (level_current < max) ? min_above : min;
1384 case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:
1385 return (level_current < max) ? min_above : max;
1386 case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:
1387 return (level_current > min) ? max_below : min;
1388 case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS:
1389 case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:
1390 return 0;
1391 default:
1392 return level_current;
1393 }
1394 }
1395
1396 static int
1397 acpi_video_switch_brightness(struct acpi_video_device *device, int event)
1398 {
1399 unsigned long long level_current, level_next;
1400 int result = -EINVAL;
1401
1402 /* no warning message if acpi_backlight=vendor or a quirk is used */
1403 if (!acpi_video_verify_backlight_support())
1404 return 0;
1405
1406 if (!device->brightness)
1407 goto out;
1408
1409 result = acpi_video_device_lcd_get_level_current(device,
1410 &level_current,
1411 false);
1412 if (result)
1413 goto out;
1414
1415 level_next = acpi_video_get_next_level(device, level_current, event);
1416
1417 result = acpi_video_device_lcd_set_level(device, level_next);
1418
1419 if (!result)
1420 backlight_force_update(device->backlight,
1421 BACKLIGHT_UPDATE_HOTKEY);
1422
1423 out:
1424 if (result)
1425 printk(KERN_ERR PREFIX "Failed to switch the brightness\n");
1426
1427 return result;
1428 }
1429
1430 int acpi_video_get_edid(struct acpi_device *device, int type, int device_id,
1431 void **edid)
1432 {
1433 struct acpi_video_bus *video;
1434 struct acpi_video_device *video_device;
1435 union acpi_object *buffer = NULL;
1436 acpi_status status;
1437 int i, length;
1438
1439 if (!device || !acpi_driver_data(device))
1440 return -EINVAL;
1441
1442 video = acpi_driver_data(device);
1443
1444 for (i = 0; i < video->attached_count; i++) {
1445 video_device = video->attached_array[i].bind_info;
1446 length = 256;
1447
1448 if (!video_device)
1449 continue;
1450
1451 if (!video_device->cap._DDC)
1452 continue;
1453
1454 if (type) {
1455 switch (type) {
1456 case ACPI_VIDEO_DISPLAY_CRT:
1457 if (!video_device->flags.crt)
1458 continue;
1459 break;
1460 case ACPI_VIDEO_DISPLAY_TV:
1461 if (!video_device->flags.tvout)
1462 continue;
1463 break;
1464 case ACPI_VIDEO_DISPLAY_DVI:
1465 if (!video_device->flags.dvi)
1466 continue;
1467 break;
1468 case ACPI_VIDEO_DISPLAY_LCD:
1469 if (!video_device->flags.lcd)
1470 continue;
1471 break;
1472 }
1473 } else if (video_device->device_id != device_id) {
1474 continue;
1475 }
1476
1477 status = acpi_video_device_EDID(video_device, &buffer, length);
1478
1479 if (ACPI_FAILURE(status) || !buffer ||
1480 buffer->type != ACPI_TYPE_BUFFER) {
1481 length = 128;
1482 status = acpi_video_device_EDID(video_device, &buffer,
1483 length);
1484 if (ACPI_FAILURE(status) || !buffer ||
1485 buffer->type != ACPI_TYPE_BUFFER) {
1486 continue;
1487 }
1488 }
1489
1490 *edid = buffer->buffer.pointer;
1491 return length;
1492 }
1493
1494 return -ENODEV;
1495 }
1496 EXPORT_SYMBOL(acpi_video_get_edid);
1497
1498 static int
1499 acpi_video_bus_get_devices(struct acpi_video_bus *video,
1500 struct acpi_device *device)
1501 {
1502 int status = 0;
1503 struct acpi_device *dev;
1504
1505 /*
1506 * There are systems where video module known to work fine regardless
1507 * of broken _DOD and ignoring returned value here doesn't cause
1508 * any issues later.
1509 */
1510 acpi_video_device_enumerate(video);
1511
1512 list_for_each_entry(dev, &device->children, node) {
1513
1514 status = acpi_video_bus_get_one_device(dev, video);
1515 if (status) {
1516 dev_err(&dev->dev, "Can't attach device\n");
1517 break;
1518 }
1519 }
1520 return status;
1521 }
1522
1523 /* acpi_video interface */
1524
1525 /*
1526 * Win8 requires setting bit2 of _DOS to let firmware know it shouldn't
1527 * preform any automatic brightness change on receiving a notification.
1528 */
1529 static int acpi_video_bus_start_devices(struct acpi_video_bus *video)
1530 {
1531 return acpi_video_bus_DOS(video, 0,
1532 acpi_osi_is_win8() ? 1 : 0);
1533 }
1534
1535 static int acpi_video_bus_stop_devices(struct acpi_video_bus *video)
1536 {
1537 return acpi_video_bus_DOS(video, 0,
1538 acpi_osi_is_win8() ? 0 : 1);
1539 }
1540
1541 static void acpi_video_bus_notify(struct acpi_device *device, u32 event)
1542 {
1543 struct acpi_video_bus *video = acpi_driver_data(device);
1544 struct input_dev *input;
1545 int keycode = 0;
1546
1547 if (!video || !video->input)
1548 return;
1549
1550 input = video->input;
1551
1552 switch (event) {
1553 case ACPI_VIDEO_NOTIFY_SWITCH: /* User requested a switch,
1554 * most likely via hotkey. */
1555 keycode = KEY_SWITCHVIDEOMODE;
1556 break;
1557
1558 case ACPI_VIDEO_NOTIFY_PROBE: /* User plugged in or removed a video
1559 * connector. */
1560 acpi_video_device_enumerate(video);
1561 acpi_video_device_rebind(video);
1562 keycode = KEY_SWITCHVIDEOMODE;
1563 break;
1564
1565 case ACPI_VIDEO_NOTIFY_CYCLE: /* Cycle Display output hotkey pressed. */
1566 keycode = KEY_SWITCHVIDEOMODE;
1567 break;
1568 case ACPI_VIDEO_NOTIFY_NEXT_OUTPUT: /* Next Display output hotkey pressed. */
1569 keycode = KEY_VIDEO_NEXT;
1570 break;
1571 case ACPI_VIDEO_NOTIFY_PREV_OUTPUT: /* previous Display output hotkey pressed. */
1572 keycode = KEY_VIDEO_PREV;
1573 break;
1574
1575 default:
1576 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1577 "Unsupported event [0x%x]\n", event));
1578 break;
1579 }
1580
1581 if (acpi_notifier_call_chain(device, event, 0))
1582 /* Something vetoed the keypress. */
1583 keycode = 0;
1584
1585 if (keycode) {
1586 input_report_key(input, keycode, 1);
1587 input_sync(input);
1588 input_report_key(input, keycode, 0);
1589 input_sync(input);
1590 }
1591
1592 return;
1593 }
1594
1595 static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data)
1596 {
1597 struct acpi_video_device *video_device = data;
1598 struct acpi_device *device = NULL;
1599 struct acpi_video_bus *bus;
1600 struct input_dev *input;
1601 int keycode = 0;
1602
1603 if (!video_device)
1604 return;
1605
1606 device = video_device->dev;
1607 bus = video_device->video;
1608 input = bus->input;
1609
1610 switch (event) {
1611 case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS: /* Cycle brightness */
1612 if (brightness_switch_enabled)
1613 acpi_video_switch_brightness(video_device, event);
1614 keycode = KEY_BRIGHTNESS_CYCLE;
1615 break;
1616 case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS: /* Increase brightness */
1617 if (brightness_switch_enabled)
1618 acpi_video_switch_brightness(video_device, event);
1619 keycode = KEY_BRIGHTNESSUP;
1620 break;
1621 case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS: /* Decrease brightness */
1622 if (brightness_switch_enabled)
1623 acpi_video_switch_brightness(video_device, event);
1624 keycode = KEY_BRIGHTNESSDOWN;
1625 break;
1626 case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS: /* zero brightness */
1627 if (brightness_switch_enabled)
1628 acpi_video_switch_brightness(video_device, event);
1629 keycode = KEY_BRIGHTNESS_ZERO;
1630 break;
1631 case ACPI_VIDEO_NOTIFY_DISPLAY_OFF: /* display device off */
1632 if (brightness_switch_enabled)
1633 acpi_video_switch_brightness(video_device, event);
1634 keycode = KEY_DISPLAY_OFF;
1635 break;
1636 default:
1637 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1638 "Unsupported event [0x%x]\n", event));
1639 break;
1640 }
1641
1642 acpi_notifier_call_chain(device, event, 0);
1643
1644 if (keycode) {
1645 input_report_key(input, keycode, 1);
1646 input_sync(input);
1647 input_report_key(input, keycode, 0);
1648 input_sync(input);
1649 }
1650
1651 return;
1652 }
1653
1654 static int acpi_video_resume(struct notifier_block *nb,
1655 unsigned long val, void *ign)
1656 {
1657 struct acpi_video_bus *video;
1658 struct acpi_video_device *video_device;
1659 int i;
1660
1661 switch (val) {
1662 case PM_HIBERNATION_PREPARE:
1663 case PM_SUSPEND_PREPARE:
1664 case PM_RESTORE_PREPARE:
1665 return NOTIFY_DONE;
1666 }
1667
1668 video = container_of(nb, struct acpi_video_bus, pm_nb);
1669
1670 dev_info(&video->device->dev, "Restoring backlight state\n");
1671
1672 for (i = 0; i < video->attached_count; i++) {
1673 video_device = video->attached_array[i].bind_info;
1674 if (video_device && video_device->backlight)
1675 acpi_video_set_brightness(video_device->backlight);
1676 }
1677
1678 return NOTIFY_OK;
1679 }
1680
1681 static acpi_status
1682 acpi_video_bus_match(acpi_handle handle, u32 level, void *context,
1683 void **return_value)
1684 {
1685 struct acpi_device *device = context;
1686 struct acpi_device *sibling;
1687 int result;
1688
1689 if (handle == device->handle)
1690 return AE_CTRL_TERMINATE;
1691
1692 result = acpi_bus_get_device(handle, &sibling);
1693 if (result)
1694 return AE_OK;
1695
1696 if (!strcmp(acpi_device_name(sibling), ACPI_VIDEO_BUS_NAME))
1697 return AE_ALREADY_EXISTS;
1698
1699 return AE_OK;
1700 }
1701
1702 static void acpi_video_dev_register_backlight(struct acpi_video_device *device)
1703 {
1704 struct backlight_properties props;
1705 struct pci_dev *pdev;
1706 acpi_handle acpi_parent;
1707 struct device *parent = NULL;
1708 int result;
1709 static int count;
1710 char *name;
1711
1712 result = acpi_video_init_brightness(device);
1713 if (result)
1714 return;
1715 name = kasprintf(GFP_KERNEL, "acpi_video%d", count);
1716 if (!name)
1717 return;
1718 count++;
1719
1720 acpi_get_parent(device->dev->handle, &acpi_parent);
1721
1722 pdev = acpi_get_pci_dev(acpi_parent);
1723 if (pdev) {
1724 parent = &pdev->dev;
1725 pci_dev_put(pdev);
1726 }
1727
1728 memset(&props, 0, sizeof(struct backlight_properties));
1729 props.type = BACKLIGHT_FIRMWARE;
1730 props.max_brightness = device->brightness->count - 3;
1731 device->backlight = backlight_device_register(name,
1732 parent,
1733 device,
1734 &acpi_backlight_ops,
1735 &props);
1736 kfree(name);
1737 if (IS_ERR(device->backlight))
1738 return;
1739
1740 /*
1741 * Save current brightness level in case we have to restore it
1742 * before acpi_video_device_lcd_set_level() is called next time.
1743 */
1744 device->backlight->props.brightness =
1745 acpi_video_get_brightness(device->backlight);
1746
1747 device->cooling_dev = thermal_cooling_device_register("LCD",
1748 device->dev, &video_cooling_ops);
1749 if (IS_ERR(device->cooling_dev)) {
1750 /*
1751 * Set cooling_dev to NULL so we don't crash trying to free it.
1752 * Also, why the hell we are returning early and not attempt to
1753 * register video output if cooling device registration failed?
1754 * -- dtor
1755 */
1756 device->cooling_dev = NULL;
1757 return;
1758 }
1759
1760 dev_info(&device->dev->dev, "registered as cooling_device%d\n",
1761 device->cooling_dev->id);
1762 result = sysfs_create_link(&device->dev->dev.kobj,
1763 &device->cooling_dev->device.kobj,
1764 "thermal_cooling");
1765 if (result)
1766 printk(KERN_ERR PREFIX "Create sysfs link\n");
1767 result = sysfs_create_link(&device->cooling_dev->device.kobj,
1768 &device->dev->dev.kobj, "device");
1769 if (result)
1770 printk(KERN_ERR PREFIX "Create sysfs link\n");
1771 }
1772
1773 static int acpi_video_bus_register_backlight(struct acpi_video_bus *video)
1774 {
1775 struct acpi_video_device *dev;
1776
1777 if (video->backlight_registered)
1778 return 0;
1779
1780 if (!acpi_video_verify_backlight_support())
1781 return 0;
1782
1783 mutex_lock(&video->device_list_lock);
1784 list_for_each_entry(dev, &video->video_device_list, entry)
1785 acpi_video_dev_register_backlight(dev);
1786 mutex_unlock(&video->device_list_lock);
1787
1788 video->backlight_registered = true;
1789
1790 video->pm_nb.notifier_call = acpi_video_resume;
1791 video->pm_nb.priority = 0;
1792 return register_pm_notifier(&video->pm_nb);
1793 }
1794
1795 static void acpi_video_dev_unregister_backlight(struct acpi_video_device *device)
1796 {
1797 if (device->backlight) {
1798 backlight_device_unregister(device->backlight);
1799 device->backlight = NULL;
1800 }
1801 if (device->brightness) {
1802 kfree(device->brightness->levels);
1803 kfree(device->brightness);
1804 device->brightness = NULL;
1805 }
1806 if (device->cooling_dev) {
1807 sysfs_remove_link(&device->dev->dev.kobj, "thermal_cooling");
1808 sysfs_remove_link(&device->cooling_dev->device.kobj, "device");
1809 thermal_cooling_device_unregister(device->cooling_dev);
1810 device->cooling_dev = NULL;
1811 }
1812 }
1813
1814 static int acpi_video_bus_unregister_backlight(struct acpi_video_bus *video)
1815 {
1816 struct acpi_video_device *dev;
1817 int error;
1818
1819 if (!video->backlight_registered)
1820 return 0;
1821
1822 error = unregister_pm_notifier(&video->pm_nb);
1823
1824 mutex_lock(&video->device_list_lock);
1825 list_for_each_entry(dev, &video->video_device_list, entry)
1826 acpi_video_dev_unregister_backlight(dev);
1827 mutex_unlock(&video->device_list_lock);
1828
1829 video->backlight_registered = false;
1830
1831 return error;
1832 }
1833
1834 static void acpi_video_dev_add_notify_handler(struct acpi_video_device *device)
1835 {
1836 acpi_status status;
1837 struct acpi_device *adev = device->dev;
1838
1839 status = acpi_install_notify_handler(adev->handle, ACPI_DEVICE_NOTIFY,
1840 acpi_video_device_notify, device);
1841 if (ACPI_FAILURE(status))
1842 dev_err(&adev->dev, "Error installing notify handler\n");
1843 else
1844 device->flags.notify = 1;
1845 }
1846
1847 static int acpi_video_bus_add_notify_handler(struct acpi_video_bus *video)
1848 {
1849 struct input_dev *input;
1850 struct acpi_video_device *dev;
1851 int error;
1852
1853 video->input = input = input_allocate_device();
1854 if (!input) {
1855 error = -ENOMEM;
1856 goto out;
1857 }
1858
1859 error = acpi_video_bus_start_devices(video);
1860 if (error)
1861 goto err_free_input;
1862
1863 snprintf(video->phys, sizeof(video->phys),
1864 "%s/video/input0", acpi_device_hid(video->device));
1865
1866 input->name = acpi_device_name(video->device);
1867 input->phys = video->phys;
1868 input->id.bustype = BUS_HOST;
1869 input->id.product = 0x06;
1870 input->dev.parent = &video->device->dev;
1871 input->evbit[0] = BIT(EV_KEY);
1872 set_bit(KEY_SWITCHVIDEOMODE, input->keybit);
1873 set_bit(KEY_VIDEO_NEXT, input->keybit);
1874 set_bit(KEY_VIDEO_PREV, input->keybit);
1875 set_bit(KEY_BRIGHTNESS_CYCLE, input->keybit);
1876 set_bit(KEY_BRIGHTNESSUP, input->keybit);
1877 set_bit(KEY_BRIGHTNESSDOWN, input->keybit);
1878 set_bit(KEY_BRIGHTNESS_ZERO, input->keybit);
1879 set_bit(KEY_DISPLAY_OFF, input->keybit);
1880
1881 error = input_register_device(input);
1882 if (error)
1883 goto err_stop_dev;
1884
1885 mutex_lock(&video->device_list_lock);
1886 list_for_each_entry(dev, &video->video_device_list, entry)
1887 acpi_video_dev_add_notify_handler(dev);
1888 mutex_unlock(&video->device_list_lock);
1889
1890 return 0;
1891
1892 err_stop_dev:
1893 acpi_video_bus_stop_devices(video);
1894 err_free_input:
1895 input_free_device(input);
1896 video->input = NULL;
1897 out:
1898 return error;
1899 }
1900
1901 static void acpi_video_dev_remove_notify_handler(struct acpi_video_device *dev)
1902 {
1903 if (dev->flags.notify) {
1904 acpi_remove_notify_handler(dev->dev->handle, ACPI_DEVICE_NOTIFY,
1905 acpi_video_device_notify);
1906 dev->flags.notify = 0;
1907 }
1908 }
1909
1910 static void acpi_video_bus_remove_notify_handler(struct acpi_video_bus *video)
1911 {
1912 struct acpi_video_device *dev;
1913
1914 mutex_lock(&video->device_list_lock);
1915 list_for_each_entry(dev, &video->video_device_list, entry)
1916 acpi_video_dev_remove_notify_handler(dev);
1917 mutex_unlock(&video->device_list_lock);
1918
1919 acpi_video_bus_stop_devices(video);
1920 input_unregister_device(video->input);
1921 video->input = NULL;
1922 }
1923
1924 static int acpi_video_backlight_notify(struct notifier_block *nb,
1925 unsigned long val, void *bd)
1926 {
1927 struct backlight_device *backlight = bd;
1928 struct acpi_video_bus *video;
1929
1930 /* acpi_video_verify_backlight_support only cares about raw devices */
1931 if (backlight->props.type != BACKLIGHT_RAW)
1932 return NOTIFY_DONE;
1933
1934 video = container_of(nb, struct acpi_video_bus, backlight_nb);
1935
1936 switch (val) {
1937 case BACKLIGHT_REGISTERED:
1938 if (!acpi_video_verify_backlight_support())
1939 acpi_video_bus_unregister_backlight(video);
1940 break;
1941 case BACKLIGHT_UNREGISTERED:
1942 acpi_video_bus_register_backlight(video);
1943 break;
1944 }
1945
1946 return NOTIFY_OK;
1947 }
1948
1949 static int acpi_video_bus_add_backlight_notify_handler(
1950 struct acpi_video_bus *video)
1951 {
1952 int error;
1953
1954 video->backlight_nb.notifier_call = acpi_video_backlight_notify;
1955 video->backlight_nb.priority = 0;
1956 error = backlight_register_notifier(&video->backlight_nb);
1957 if (error == 0)
1958 video->backlight_notifier_registered = true;
1959
1960 return error;
1961 }
1962
1963 static int acpi_video_bus_remove_backlight_notify_handler(
1964 struct acpi_video_bus *video)
1965 {
1966 if (!video->backlight_notifier_registered)
1967 return 0;
1968
1969 video->backlight_notifier_registered = false;
1970
1971 return backlight_unregister_notifier(&video->backlight_nb);
1972 }
1973
1974 static int acpi_video_bus_put_devices(struct acpi_video_bus *video)
1975 {
1976 struct acpi_video_device *dev, *next;
1977
1978 mutex_lock(&video->device_list_lock);
1979 list_for_each_entry_safe(dev, next, &video->video_device_list, entry) {
1980 list_del(&dev->entry);
1981 kfree(dev);
1982 }
1983 mutex_unlock(&video->device_list_lock);
1984
1985 return 0;
1986 }
1987
1988 static int instance;
1989
1990 static int acpi_video_bus_add(struct acpi_device *device)
1991 {
1992 struct acpi_video_bus *video;
1993 int error;
1994 acpi_status status;
1995
1996 status = acpi_walk_namespace(ACPI_TYPE_DEVICE,
1997 device->parent->handle, 1,
1998 acpi_video_bus_match, NULL,
1999 device, NULL);
2000 if (status == AE_ALREADY_EXISTS) {
2001 printk(KERN_WARNING FW_BUG
2002 "Duplicate ACPI video bus devices for the"
2003 " same VGA controller, please try module "
2004 "parameter \"video.allow_duplicates=1\""
2005 "if the current driver doesn't work.\n");
2006 if (!allow_duplicates)
2007 return -ENODEV;
2008 }
2009
2010 video = kzalloc(sizeof(struct acpi_video_bus), GFP_KERNEL);
2011 if (!video)
2012 return -ENOMEM;
2013
2014 /* a hack to fix the duplicate name "VID" problem on T61 */
2015 if (!strcmp(device->pnp.bus_id, "VID")) {
2016 if (instance)
2017 device->pnp.bus_id[3] = '0' + instance;
2018 instance++;
2019 }
2020 /* a hack to fix the duplicate name "VGA" problem on Pa 3553 */
2021 if (!strcmp(device->pnp.bus_id, "VGA")) {
2022 if (instance)
2023 device->pnp.bus_id[3] = '0' + instance;
2024 instance++;
2025 }
2026
2027 video->device = device;
2028 strcpy(acpi_device_name(device), ACPI_VIDEO_BUS_NAME);
2029 strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
2030 device->driver_data = video;
2031
2032 acpi_video_bus_find_cap(video);
2033 error = acpi_video_bus_check(video);
2034 if (error)
2035 goto err_free_video;
2036
2037 mutex_init(&video->device_list_lock);
2038 INIT_LIST_HEAD(&video->video_device_list);
2039
2040 error = acpi_video_bus_get_devices(video, device);
2041 if (error)
2042 goto err_put_video;
2043
2044 printk(KERN_INFO PREFIX "%s [%s] (multi-head: %s rom: %s post: %s)\n",
2045 ACPI_VIDEO_DEVICE_NAME, acpi_device_bid(device),
2046 video->flags.multihead ? "yes" : "no",
2047 video->flags.rom ? "yes" : "no",
2048 video->flags.post ? "yes" : "no");
2049 mutex_lock(&video_list_lock);
2050 list_add_tail(&video->entry, &video_bus_head);
2051 mutex_unlock(&video_list_lock);
2052
2053 acpi_video_bus_register_backlight(video);
2054 acpi_video_bus_add_notify_handler(video);
2055 acpi_video_bus_add_backlight_notify_handler(video);
2056
2057 return 0;
2058
2059 err_put_video:
2060 acpi_video_bus_put_devices(video);
2061 kfree(video->attached_array);
2062 err_free_video:
2063 kfree(video);
2064 device->driver_data = NULL;
2065
2066 return error;
2067 }
2068
2069 static int acpi_video_bus_remove(struct acpi_device *device)
2070 {
2071 struct acpi_video_bus *video = NULL;
2072
2073
2074 if (!device || !acpi_driver_data(device))
2075 return -EINVAL;
2076
2077 video = acpi_driver_data(device);
2078
2079 acpi_video_bus_remove_backlight_notify_handler(video);
2080 acpi_video_bus_remove_notify_handler(video);
2081 acpi_video_bus_unregister_backlight(video);
2082 acpi_video_bus_put_devices(video);
2083
2084 mutex_lock(&video_list_lock);
2085 list_del(&video->entry);
2086 mutex_unlock(&video_list_lock);
2087
2088 kfree(video->attached_array);
2089 kfree(video);
2090
2091 return 0;
2092 }
2093
2094 static int __init is_i740(struct pci_dev *dev)
2095 {
2096 if (dev->device == 0x00D1)
2097 return 1;
2098 if (dev->device == 0x7000)
2099 return 1;
2100 return 0;
2101 }
2102
2103 static int __init intel_opregion_present(void)
2104 {
2105 int opregion = 0;
2106 struct pci_dev *dev = NULL;
2107 u32 address;
2108
2109 for_each_pci_dev(dev) {
2110 if ((dev->class >> 8) != PCI_CLASS_DISPLAY_VGA)
2111 continue;
2112 if (dev->vendor != PCI_VENDOR_ID_INTEL)
2113 continue;
2114 /* We don't want to poke around undefined i740 registers */
2115 if (is_i740(dev))
2116 continue;
2117 pci_read_config_dword(dev, 0xfc, &address);
2118 if (!address)
2119 continue;
2120 opregion = 1;
2121 }
2122 return opregion;
2123 }
2124
2125 int acpi_video_register(void)
2126 {
2127 int result = 0;
2128 if (register_count) {
2129 /*
2130 * if the function of acpi_video_register is already called,
2131 * don't register the acpi_vide_bus again and return no error.
2132 */
2133 return 0;
2134 }
2135
2136 mutex_init(&video_list_lock);
2137 INIT_LIST_HEAD(&video_bus_head);
2138
2139 result = acpi_bus_register_driver(&acpi_video_bus);
2140 if (result < 0)
2141 return -ENODEV;
2142
2143 /*
2144 * When the acpi_video_bus is loaded successfully, increase
2145 * the counter reference.
2146 */
2147 register_count = 1;
2148
2149 return 0;
2150 }
2151 EXPORT_SYMBOL(acpi_video_register);
2152
2153 void acpi_video_unregister(void)
2154 {
2155 if (!register_count) {
2156 /*
2157 * If the acpi video bus is already unloaded, don't
2158 * unload it again and return directly.
2159 */
2160 return;
2161 }
2162 acpi_bus_unregister_driver(&acpi_video_bus);
2163
2164 register_count = 0;
2165
2166 return;
2167 }
2168 EXPORT_SYMBOL(acpi_video_unregister);
2169
2170 void acpi_video_unregister_backlight(void)
2171 {
2172 struct acpi_video_bus *video;
2173
2174 if (!register_count)
2175 return;
2176
2177 mutex_lock(&video_list_lock);
2178 list_for_each_entry(video, &video_bus_head, entry)
2179 acpi_video_bus_unregister_backlight(video);
2180 mutex_unlock(&video_list_lock);
2181 }
2182 EXPORT_SYMBOL(acpi_video_unregister_backlight);
2183
2184 /*
2185 * This is kind of nasty. Hardware using Intel chipsets may require
2186 * the video opregion code to be run first in order to initialise
2187 * state before any ACPI video calls are made. To handle this we defer
2188 * registration of the video class until the opregion code has run.
2189 */
2190
2191 static int __init acpi_video_init(void)
2192 {
2193 dmi_check_system(video_dmi_table);
2194
2195 if (intel_opregion_present())
2196 return 0;
2197
2198 return acpi_video_register();
2199 }
2200
2201 static void __exit acpi_video_exit(void)
2202 {
2203 acpi_video_unregister();
2204
2205 return;
2206 }
2207
2208 module_init(acpi_video_init);
2209 module_exit(acpi_video_exit);
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