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xfs: fix compiler warnings
[linux/fpc-iii.git] / drivers / acpi / acpi_video.c
blobc5557d070954c6a7bbf8799b0f2cc4ee593a14d4
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 <asm/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 #define ACPI_VIDEO_NOTIFY_SWITCH 0x80
47 #define ACPI_VIDEO_NOTIFY_PROBE 0x81
48 #define ACPI_VIDEO_NOTIFY_CYCLE 0x82
49 #define ACPI_VIDEO_NOTIFY_NEXT_OUTPUT 0x83
50 #define ACPI_VIDEO_NOTIFY_PREV_OUTPUT 0x84
51
52 #define ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS 0x85
53 #define ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS 0x86
54 #define ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS 0x87
55 #define ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS 0x88
56 #define ACPI_VIDEO_NOTIFY_DISPLAY_OFF 0x89
57
58 #define MAX_NAME_LEN 20
59
60 #define _COMPONENT ACPI_VIDEO_COMPONENT
61 ACPI_MODULE_NAME("video");
62
63 MODULE_AUTHOR("Bruno Ducrot");
64 MODULE_DESCRIPTION("ACPI Video Driver");
65 MODULE_LICENSE("GPL");
66
67 static bool brightness_switch_enabled = 1;
68 module_param(brightness_switch_enabled, bool, 0644);
69
70 /*
71 * By default, we don't allow duplicate ACPI video bus devices
72 * under the same VGA controller
73 */
74 static bool allow_duplicates;
75 module_param(allow_duplicates, bool, 0644);
76
77 static int disable_backlight_sysfs_if = -1;
78 module_param(disable_backlight_sysfs_if, int, 0444);
79
80 #define REPORT_OUTPUT_KEY_EVENTS 0x01
81 #define REPORT_BRIGHTNESS_KEY_EVENTS 0x02
82 static int report_key_events = -1;
83 module_param(report_key_events, int, 0644);
84 MODULE_PARM_DESC(report_key_events,
85 "0: none, 1: output changes, 2: brightness changes, 3: all");
86
87 static bool device_id_scheme = false;
88 module_param(device_id_scheme, bool, 0444);
89
90 static bool only_lcd = false;
91 module_param(only_lcd, bool, 0444);
92
93 static int register_count;
94 static DEFINE_MUTEX(register_count_mutex);
95 static DEFINE_MUTEX(video_list_lock);
96 static LIST_HEAD(video_bus_head);
97 static int acpi_video_bus_add(struct acpi_device *device);
98 static int acpi_video_bus_remove(struct acpi_device *device);
99 static void acpi_video_bus_notify(struct acpi_device *device, u32 event);
100 void acpi_video_detect_exit(void);
101
102 static const struct acpi_device_id video_device_ids[] = {
103 {ACPI_VIDEO_HID, 0},
104 {"", 0},
105 };
106 MODULE_DEVICE_TABLE(acpi, video_device_ids);
107
108 static struct acpi_driver acpi_video_bus = {
109 .name = "video",
110 .class = ACPI_VIDEO_CLASS,
111 .ids = video_device_ids,
112 .ops = {
113 .add = acpi_video_bus_add,
114 .remove = acpi_video_bus_remove,
115 .notify = acpi_video_bus_notify,
116 },
117 };
118
119 struct acpi_video_bus_flags {
120 u8 multihead:1; /* can switch video heads */
121 u8 rom:1; /* can retrieve a video rom */
122 u8 post:1; /* can configure the head to */
123 u8 reserved:5;
124 };
125
126 struct acpi_video_bus_cap {
127 u8 _DOS:1; /* Enable/Disable output switching */
128 u8 _DOD:1; /* Enumerate all devices attached to display adapter */
129 u8 _ROM:1; /* Get ROM Data */
130 u8 _GPD:1; /* Get POST Device */
131 u8 _SPD:1; /* Set POST Device */
132 u8 _VPO:1; /* Video POST Options */
133 u8 reserved:2;
134 };
135
136 struct acpi_video_device_attrib {
137 u32 display_index:4; /* A zero-based instance of the Display */
138 u32 display_port_attachment:4; /* This field differentiates the display type */
139 u32 display_type:4; /* Describe the specific type in use */
140 u32 vendor_specific:4; /* Chipset Vendor Specific */
141 u32 bios_can_detect:1; /* BIOS can detect the device */
142 u32 depend_on_vga:1; /* Non-VGA output device whose power is related to
143 the VGA device. */
144 u32 pipe_id:3; /* For VGA multiple-head devices. */
145 u32 reserved:10; /* Must be 0 */
146 u32 device_id_scheme:1; /* Device ID Scheme */
147 };
148
149 struct acpi_video_enumerated_device {
150 union {
151 u32 int_val;
152 struct acpi_video_device_attrib attrib;
153 } value;
154 struct acpi_video_device *bind_info;
155 };
156
157 struct acpi_video_bus {
158 struct acpi_device *device;
159 bool backlight_registered;
160 u8 dos_setting;
161 struct acpi_video_enumerated_device *attached_array;
162 u8 attached_count;
163 u8 child_count;
164 struct acpi_video_bus_cap cap;
165 struct acpi_video_bus_flags flags;
166 struct list_head video_device_list;
167 struct mutex device_list_lock; /* protects video_device_list */
168 struct list_head entry;
169 struct input_dev *input;
170 char phys[32]; /* for input device */
171 struct notifier_block pm_nb;
172 };
173
174 struct acpi_video_device_flags {
175 u8 crt:1;
176 u8 lcd:1;
177 u8 tvout:1;
178 u8 dvi:1;
179 u8 bios:1;
180 u8 unknown:1;
181 u8 notify:1;
182 u8 reserved:1;
183 };
184
185 struct acpi_video_device_cap {
186 u8 _ADR:1; /* Return the unique ID */
187 u8 _BCL:1; /* Query list of brightness control levels supported */
188 u8 _BCM:1; /* Set the brightness level */
189 u8 _BQC:1; /* Get current brightness level */
190 u8 _BCQ:1; /* Some buggy BIOS uses _BCQ instead of _BQC */
191 u8 _DDC:1; /* Return the EDID for this device */
192 };
193
194 struct acpi_video_device {
195 unsigned long device_id;
196 struct acpi_video_device_flags flags;
197 struct acpi_video_device_cap cap;
198 struct list_head entry;
199 struct delayed_work switch_brightness_work;
200 int switch_brightness_event;
201 struct acpi_video_bus *video;
202 struct acpi_device *dev;
203 struct acpi_video_device_brightness *brightness;
204 struct backlight_device *backlight;
205 struct thermal_cooling_device *cooling_dev;
206 };
207
208 static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data);
209 static void acpi_video_device_rebind(struct acpi_video_bus *video);
210 static void acpi_video_device_bind(struct acpi_video_bus *video,
211 struct acpi_video_device *device);
212 static int acpi_video_device_enumerate(struct acpi_video_bus *video);
213 static int acpi_video_device_lcd_set_level(struct acpi_video_device *device,
214 int level);
215 static int acpi_video_device_lcd_get_level_current(
216 struct acpi_video_device *device,
217 unsigned long long *level, bool raw);
218 static int acpi_video_get_next_level(struct acpi_video_device *device,
219 u32 level_current, u32 event);
220 static void acpi_video_switch_brightness(struct work_struct *work);
221
222 /* backlight device sysfs support */
223 static int acpi_video_get_brightness(struct backlight_device *bd)
224 {
225 unsigned long long cur_level;
226 int i;
227 struct acpi_video_device *vd = bl_get_data(bd);
228
229 if (acpi_video_device_lcd_get_level_current(vd, &cur_level, false))
230 return -EINVAL;
231 for (i = 2; i < vd->brightness->count; i++) {
232 if (vd->brightness->levels[i] == cur_level)
233 /*
234 * The first two entries are special - see page 575
235 * of the ACPI spec 3.0
236 */
237 return i - 2;
238 }
239 return 0;
240 }
241
242 static int acpi_video_set_brightness(struct backlight_device *bd)
243 {
244 int request_level = bd->props.brightness + 2;
245 struct acpi_video_device *vd = bl_get_data(bd);
246
247 cancel_delayed_work(&vd->switch_brightness_work);
248 return acpi_video_device_lcd_set_level(vd,
249 vd->brightness->levels[request_level]);
250 }
251
252 static const struct backlight_ops acpi_backlight_ops = {
253 .get_brightness = acpi_video_get_brightness,
254 .update_status = acpi_video_set_brightness,
255 };
256
257 /* thermal cooling device callbacks */
258 static int video_get_max_state(struct thermal_cooling_device *cooling_dev, unsigned
259 long *state)
260 {
261 struct acpi_device *device = cooling_dev->devdata;
262 struct acpi_video_device *video = acpi_driver_data(device);
263
264 *state = video->brightness->count - 3;
265 return 0;
266 }
267
268 static int video_get_cur_state(struct thermal_cooling_device *cooling_dev, unsigned
269 long *state)
270 {
271 struct acpi_device *device = cooling_dev->devdata;
272 struct acpi_video_device *video = acpi_driver_data(device);
273 unsigned long long level;
274 int offset;
275
276 if (acpi_video_device_lcd_get_level_current(video, &level, false))
277 return -EINVAL;
278 for (offset = 2; offset < video->brightness->count; offset++)
279 if (level == video->brightness->levels[offset]) {
280 *state = video->brightness->count - offset - 1;
281 return 0;
282 }
283
284 return -EINVAL;
285 }
286
287 static int
288 video_set_cur_state(struct thermal_cooling_device *cooling_dev, unsigned long state)
289 {
290 struct acpi_device *device = cooling_dev->devdata;
291 struct acpi_video_device *video = acpi_driver_data(device);
292 int level;
293
294 if (state >= video->brightness->count - 2)
295 return -EINVAL;
296
297 state = video->brightness->count - state;
298 level = video->brightness->levels[state - 1];
299 return acpi_video_device_lcd_set_level(video, level);
300 }
301
302 static const struct thermal_cooling_device_ops video_cooling_ops = {
303 .get_max_state = video_get_max_state,
304 .get_cur_state = video_get_cur_state,
305 .set_cur_state = video_set_cur_state,
306 };
307
308 /*
309 * --------------------------------------------------------------------------
310 * Video Management
311 * --------------------------------------------------------------------------
312 */
313
314 static int
315 acpi_video_device_lcd_query_levels(acpi_handle handle,
316 union acpi_object **levels)
317 {
318 int status;
319 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
320 union acpi_object *obj;
321
322
323 *levels = NULL;
324
325 status = acpi_evaluate_object(handle, "_BCL", NULL, &buffer);
326 if (!ACPI_SUCCESS(status))
327 return status;
328 obj = (union acpi_object *)buffer.pointer;
329 if (!obj || (obj->type != ACPI_TYPE_PACKAGE)) {
330 printk(KERN_ERR PREFIX "Invalid _BCL data\n");
331 status = -EFAULT;
332 goto err;
333 }
334
335 *levels = obj;
336
337 return 0;
338
339 err:
340 kfree(buffer.pointer);
341
342 return status;
343 }
344
345 static int
346 acpi_video_device_lcd_set_level(struct acpi_video_device *device, int level)
347 {
348 int status;
349 int state;
350
351 status = acpi_execute_simple_method(device->dev->handle,
352 "_BCM", level);
353 if (ACPI_FAILURE(status)) {
354 ACPI_ERROR((AE_INFO, "Evaluating _BCM failed"));
355 return -EIO;
356 }
357
358 device->brightness->curr = level;
359 for (state = 2; state < device->brightness->count; state++)
360 if (level == device->brightness->levels[state]) {
361 if (device->backlight)
362 device->backlight->props.brightness = state - 2;
363 return 0;
364 }
365
366 ACPI_ERROR((AE_INFO, "Current brightness invalid"));
367 return -EINVAL;
368 }
369
370 /*
371 * For some buggy _BQC methods, we need to add a constant value to
372 * the _BQC return value to get the actual current brightness level
373 */
374
375 static int bqc_offset_aml_bug_workaround;
376 static int video_set_bqc_offset(const struct dmi_system_id *d)
377 {
378 bqc_offset_aml_bug_workaround = 9;
379 return 0;
380 }
381
382 static int video_disable_backlight_sysfs_if(
383 const struct dmi_system_id *d)
384 {
385 if (disable_backlight_sysfs_if == -1)
386 disable_backlight_sysfs_if = 1;
387 return 0;
388 }
389
390 static int video_set_device_id_scheme(const struct dmi_system_id *d)
391 {
392 device_id_scheme = true;
393 return 0;
394 }
395
396 static int video_enable_only_lcd(const struct dmi_system_id *d)
397 {
398 only_lcd = true;
399 return 0;
400 }
401
402 static int video_set_report_key_events(const struct dmi_system_id *id)
403 {
404 if (report_key_events == -1)
405 report_key_events = (uintptr_t)id->driver_data;
406 return 0;
407 }
408
409 static struct dmi_system_id video_dmi_table[] = {
410 /*
411 * Broken _BQC workaround http://bugzilla.kernel.org/show_bug.cgi?id=13121
412 */
413 {
414 .callback = video_set_bqc_offset,
415 .ident = "Acer Aspire 5720",
416 .matches = {
417 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
418 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5720"),
419 },
420 },
421 {
422 .callback = video_set_bqc_offset,
423 .ident = "Acer Aspire 5710Z",
424 .matches = {
425 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
426 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5710Z"),
427 },
428 },
429 {
430 .callback = video_set_bqc_offset,
431 .ident = "eMachines E510",
432 .matches = {
433 DMI_MATCH(DMI_BOARD_VENDOR, "EMACHINES"),
434 DMI_MATCH(DMI_PRODUCT_NAME, "eMachines E510"),
435 },
436 },
437 {
438 .callback = video_set_bqc_offset,
439 .ident = "Acer Aspire 5315",
440 .matches = {
441 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
442 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5315"),
443 },
444 },
445 {
446 .callback = video_set_bqc_offset,
447 .ident = "Acer Aspire 7720",
448 .matches = {
449 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
450 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 7720"),
451 },
452 },
453
454 /*
455 * Some machines have a broken acpi-video interface for brightness
456 * control, but still need an acpi_video_device_lcd_set_level() call
457 * on resume to turn the backlight power on. We Enable backlight
458 * control on these systems, but do not register a backlight sysfs
459 * as brightness control does not work.
460 */
461 {
462 /* https://bugzilla.kernel.org/show_bug.cgi?id=21012 */
463 .callback = video_disable_backlight_sysfs_if,
464 .ident = "Toshiba Portege R700",
465 .matches = {
466 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
467 DMI_MATCH(DMI_PRODUCT_NAME, "PORTEGE R700"),
468 },
469 },
470 {
471 /* https://bugs.freedesktop.org/show_bug.cgi?id=82634 */
472 .callback = video_disable_backlight_sysfs_if,
473 .ident = "Toshiba Portege R830",
474 .matches = {
475 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
476 DMI_MATCH(DMI_PRODUCT_NAME, "PORTEGE R830"),
477 },
478 },
479 {
480 /* https://bugzilla.kernel.org/show_bug.cgi?id=21012 */
481 .callback = video_disable_backlight_sysfs_if,
482 .ident = "Toshiba Satellite R830",
483 .matches = {
484 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
485 DMI_MATCH(DMI_PRODUCT_NAME, "SATELLITE R830"),
486 },
487 },
488 /*
489 * Some machine's _DOD IDs don't have bit 31(Device ID Scheme) set
490 * but the IDs actually follow the Device ID Scheme.
491 */
492 {
493 /* https://bugzilla.kernel.org/show_bug.cgi?id=104121 */
494 .callback = video_set_device_id_scheme,
495 .ident = "ESPRIMO Mobile M9410",
496 .matches = {
497 DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU SIEMENS"),
498 DMI_MATCH(DMI_PRODUCT_NAME, "ESPRIMO Mobile M9410"),
499 },
500 },
501 /*
502 * Some machines have multiple video output devices, but only the one
503 * that is the type of LCD can do the backlight control so we should not
504 * register backlight interface for other video output devices.
505 */
506 {
507 /* https://bugzilla.kernel.org/show_bug.cgi?id=104121 */
508 .callback = video_enable_only_lcd,
509 .ident = "ESPRIMO Mobile M9410",
510 .matches = {
511 DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU SIEMENS"),
512 DMI_MATCH(DMI_PRODUCT_NAME, "ESPRIMO Mobile M9410"),
513 },
514 },
515 /*
516 * Some machines report wrong key events on the acpi-bus, suppress
517 * key event reporting on these. Note this is only intended to work
518 * around events which are plain wrong. In some cases we get double
519 * events, in this case acpi-video is considered the canonical source
520 * and the events from the other source should be filtered. E.g.
521 * by calling acpi_video_handles_brightness_key_presses() from the
522 * vendor acpi/wmi driver or by using /lib/udev/hwdb.d/60-keyboard.hwdb
523 */
524 {
525 .callback = video_set_report_key_events,
526 .driver_data = (void *)((uintptr_t)REPORT_OUTPUT_KEY_EVENTS),
527 .ident = "Dell Vostro V131",
528 .matches = {
529 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
530 DMI_MATCH(DMI_PRODUCT_NAME, "Vostro V131"),
531 },
532 },
533 {}
534 };
535
536 static unsigned long long
537 acpi_video_bqc_value_to_level(struct acpi_video_device *device,
538 unsigned long long bqc_value)
539 {
540 unsigned long long level;
541
542 if (device->brightness->flags._BQC_use_index) {
543 /*
544 * _BQC returns an index that doesn't account for
545 * the first 2 items with special meaning, so we need
546 * to compensate for that by offsetting ourselves
547 */
548 if (device->brightness->flags._BCL_reversed)
549 bqc_value = device->brightness->count - 3 - bqc_value;
550
551 level = device->brightness->levels[bqc_value + 2];
552 } else {
553 level = bqc_value;
554 }
555
556 level += bqc_offset_aml_bug_workaround;
557
558 return level;
559 }
560
561 static int
562 acpi_video_device_lcd_get_level_current(struct acpi_video_device *device,
563 unsigned long long *level, bool raw)
564 {
565 acpi_status status = AE_OK;
566 int i;
567
568 if (device->cap._BQC || device->cap._BCQ) {
569 char *buf = device->cap._BQC ? "_BQC" : "_BCQ";
570
571 status = acpi_evaluate_integer(device->dev->handle, buf,
572 NULL, level);
573 if (ACPI_SUCCESS(status)) {
574 if (raw) {
575 /*
576 * Caller has indicated he wants the raw
577 * value returned by _BQC, so don't furtherly
578 * mess with the value.
579 */
580 return 0;
581 }
582
583 *level = acpi_video_bqc_value_to_level(device, *level);
584
585 for (i = 2; i < device->brightness->count; i++)
586 if (device->brightness->levels[i] == *level) {
587 device->brightness->curr = *level;
588 return 0;
589 }
590 /*
591 * BQC returned an invalid level.
592 * Stop using it.
593 */
594 ACPI_WARNING((AE_INFO,
595 "%s returned an invalid level",
596 buf));
597 device->cap._BQC = device->cap._BCQ = 0;
598 } else {
599 /*
600 * Fixme:
601 * should we return an error or ignore this failure?
602 * dev->brightness->curr is a cached value which stores
603 * the correct current backlight level in most cases.
604 * ACPI video backlight still works w/ buggy _BQC.
605 * http://bugzilla.kernel.org/show_bug.cgi?id=12233
606 */
607 ACPI_WARNING((AE_INFO, "Evaluating %s failed", buf));
608 device->cap._BQC = device->cap._BCQ = 0;
609 }
610 }
611
612 *level = device->brightness->curr;
613 return 0;
614 }
615
616 static int
617 acpi_video_device_EDID(struct acpi_video_device *device,
618 union acpi_object **edid, ssize_t length)
619 {
620 int status;
621 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
622 union acpi_object *obj;
623 union acpi_object arg0 = { ACPI_TYPE_INTEGER };
624 struct acpi_object_list args = { 1, &arg0 };
625
626
627 *edid = NULL;
628
629 if (!device)
630 return -ENODEV;
631 if (length == 128)
632 arg0.integer.value = 1;
633 else if (length == 256)
634 arg0.integer.value = 2;
635 else
636 return -EINVAL;
637
638 status = acpi_evaluate_object(device->dev->handle, "_DDC", &args, &buffer);
639 if (ACPI_FAILURE(status))
640 return -ENODEV;
641
642 obj = buffer.pointer;
643
644 if (obj && obj->type == ACPI_TYPE_BUFFER)
645 *edid = obj;
646 else {
647 printk(KERN_ERR PREFIX "Invalid _DDC data\n");
648 status = -EFAULT;
649 kfree(obj);
650 }
651
652 return status;
653 }
654
655 /* bus */
656
657 /*
658 * Arg:
659 * video : video bus device pointer
660 * bios_flag :
661 * 0. The system BIOS should NOT automatically switch(toggle)
662 * the active display output.
663 * 1. The system BIOS should automatically switch (toggle) the
664 * active display output. No switch event.
665 * 2. The _DGS value should be locked.
666 * 3. The system BIOS should not automatically switch (toggle) the
667 * active display output, but instead generate the display switch
668 * event notify code.
669 * lcd_flag :
670 * 0. The system BIOS should automatically control the brightness level
671 * of the LCD when the power changes from AC to DC
672 * 1. The system BIOS should NOT automatically control the brightness
673 * level of the LCD when the power changes from AC to DC.
674 * Return Value:
675 * -EINVAL wrong arg.
676 */
677
678 static int
679 acpi_video_bus_DOS(struct acpi_video_bus *video, int bios_flag, int lcd_flag)
680 {
681 acpi_status status;
682
683 if (!video->cap._DOS)
684 return 0;
685
686 if (bios_flag < 0 || bios_flag > 3 || lcd_flag < 0 || lcd_flag > 1)
687 return -EINVAL;
688 video->dos_setting = (lcd_flag << 2) | bios_flag;
689 status = acpi_execute_simple_method(video->device->handle, "_DOS",
690 (lcd_flag << 2) | bios_flag);
691 if (ACPI_FAILURE(status))
692 return -EIO;
693
694 return 0;
695 }
696
697 /*
698 * Simple comparison function used to sort backlight levels.
699 */
700
701 static int
702 acpi_video_cmp_level(const void *a, const void *b)
703 {
704 return *(int *)a - *(int *)b;
705 }
706
707 /*
708 * Decides if _BQC/_BCQ for this system is usable
709 *
710 * We do this by changing the level first and then read out the current
711 * brightness level, if the value does not match, find out if it is using
712 * index. If not, clear the _BQC/_BCQ capability.
713 */
714 static int acpi_video_bqc_quirk(struct acpi_video_device *device,
715 int max_level, int current_level)
716 {
717 struct acpi_video_device_brightness *br = device->brightness;
718 int result;
719 unsigned long long level;
720 int test_level;
721
722 /* don't mess with existing known broken systems */
723 if (bqc_offset_aml_bug_workaround)
724 return 0;
725
726 /*
727 * Some systems always report current brightness level as maximum
728 * through _BQC, we need to test another value for them.
729 */
730 test_level = current_level == max_level ? br->levels[3] : max_level;
731
732 result = acpi_video_device_lcd_set_level(device, test_level);
733 if (result)
734 return result;
735
736 result = acpi_video_device_lcd_get_level_current(device, &level, true);
737 if (result)
738 return result;
739
740 if (level != test_level) {
741 /* buggy _BQC found, need to find out if it uses index */
742 if (level < br->count) {
743 if (br->flags._BCL_reversed)
744 level = br->count - 3 - level;
745 if (br->levels[level + 2] == test_level)
746 br->flags._BQC_use_index = 1;
747 }
748
749 if (!br->flags._BQC_use_index)
750 device->cap._BQC = device->cap._BCQ = 0;
751 }
752
753 return 0;
754 }
755
756 int acpi_video_get_levels(struct acpi_device *device,
757 struct acpi_video_device_brightness **dev_br,
758 int *pmax_level)
759 {
760 union acpi_object *obj = NULL;
761 int i, max_level = 0, count = 0, level_ac_battery = 0;
762 union acpi_object *o;
763 struct acpi_video_device_brightness *br = NULL;
764 int result = 0;
765 u32 value;
766
767 if (!ACPI_SUCCESS(acpi_video_device_lcd_query_levels(device->handle,
768 &obj))) {
769 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Could not query available "
770 "LCD brightness level\n"));
771 result = -ENODEV;
772 goto out;
773 }
774
775 if (obj->package.count < 2) {
776 result = -EINVAL;
777 goto out;
778 }
779
780 br = kzalloc(sizeof(*br), GFP_KERNEL);
781 if (!br) {
782 printk(KERN_ERR "can't allocate memory\n");
783 result = -ENOMEM;
784 goto out;
785 }
786
787 br->levels = kmalloc((obj->package.count + 2) * sizeof *(br->levels),
788 GFP_KERNEL);
789 if (!br->levels) {
790 result = -ENOMEM;
791 goto out_free;
792 }
793
794 for (i = 0; i < obj->package.count; i++) {
795 o = (union acpi_object *)&obj->package.elements[i];
796 if (o->type != ACPI_TYPE_INTEGER) {
797 printk(KERN_ERR PREFIX "Invalid data\n");
798 continue;
799 }
800 value = (u32) o->integer.value;
801 /* Skip duplicate entries */
802 if (count > 2 && br->levels[count - 1] == value)
803 continue;
804
805 br->levels[count] = value;
806
807 if (br->levels[count] > max_level)
808 max_level = br->levels[count];
809 count++;
810 }
811
812 /*
813 * some buggy BIOS don't export the levels
814 * when machine is on AC/Battery in _BCL package.
815 * In this case, the first two elements in _BCL packages
816 * are also supported brightness levels that OS should take care of.
817 */
818 for (i = 2; i < count; i++) {
819 if (br->levels[i] == br->levels[0])
820 level_ac_battery++;
821 if (br->levels[i] == br->levels[1])
822 level_ac_battery++;
823 }
824
825 if (level_ac_battery < 2) {
826 level_ac_battery = 2 - level_ac_battery;
827 br->flags._BCL_no_ac_battery_levels = 1;
828 for (i = (count - 1 + level_ac_battery); i >= 2; i--)
829 br->levels[i] = br->levels[i - level_ac_battery];
830 count += level_ac_battery;
831 } else if (level_ac_battery > 2)
832 ACPI_ERROR((AE_INFO, "Too many duplicates in _BCL package"));
833
834 /* Check if the _BCL package is in a reversed order */
835 if (max_level == br->levels[2]) {
836 br->flags._BCL_reversed = 1;
837 sort(&br->levels[2], count - 2, sizeof(br->levels[2]),
838 acpi_video_cmp_level, NULL);
839 } else if (max_level != br->levels[count - 1])
840 ACPI_ERROR((AE_INFO,
841 "Found unordered _BCL package"));
842
843 br->count = count;
844 *dev_br = br;
845 if (pmax_level)
846 *pmax_level = max_level;
847
848 out:
849 kfree(obj);
850 return result;
851 out_free:
852 kfree(br);
853 goto out;
854 }
855 EXPORT_SYMBOL(acpi_video_get_levels);
856
857 /*
858 * Arg:
859 * device : video output device (LCD, CRT, ..)
860 *
861 * Return Value:
862 * Maximum brightness level
863 *
864 * Allocate and initialize device->brightness.
865 */
866
867 static int
868 acpi_video_init_brightness(struct acpi_video_device *device)
869 {
870 int i, max_level = 0;
871 unsigned long long level, level_old;
872 struct acpi_video_device_brightness *br = NULL;
873 int result = -EINVAL;
874
875 result = acpi_video_get_levels(device->dev, &br, &max_level);
876 if (result)
877 return result;
878 device->brightness = br;
879
880 /* _BQC uses INDEX while _BCL uses VALUE in some laptops */
881 br->curr = level = max_level;
882
883 if (!device->cap._BQC)
884 goto set_level;
885
886 result = acpi_video_device_lcd_get_level_current(device,
887 &level_old, true);
888 if (result)
889 goto out_free_levels;
890
891 result = acpi_video_bqc_quirk(device, max_level, level_old);
892 if (result)
893 goto out_free_levels;
894 /*
895 * cap._BQC may get cleared due to _BQC is found to be broken
896 * in acpi_video_bqc_quirk, so check again here.
897 */
898 if (!device->cap._BQC)
899 goto set_level;
900
901 level = acpi_video_bqc_value_to_level(device, level_old);
902 /*
903 * On some buggy laptops, _BQC returns an uninitialized
904 * value when invoked for the first time, i.e.
905 * level_old is invalid (no matter whether it's a level
906 * or an index). Set the backlight to max_level in this case.
907 */
908 for (i = 2; i < br->count; i++)
909 if (level == br->levels[i])
910 break;
911 if (i == br->count || !level)
912 level = max_level;
913
914 set_level:
915 result = acpi_video_device_lcd_set_level(device, level);
916 if (result)
917 goto out_free_levels;
918
919 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
920 "found %d brightness levels\n", br->count - 2));
921 return 0;
922
923 out_free_levels:
924 kfree(br->levels);
925 kfree(br);
926 device->brightness = NULL;
927 return result;
928 }
929
930 /*
931 * Arg:
932 * device : video output device (LCD, CRT, ..)
933 *
934 * Return Value:
935 * None
936 *
937 * Find out all required AML methods defined under the output
938 * device.
939 */
940
941 static void acpi_video_device_find_cap(struct acpi_video_device *device)
942 {
943 if (acpi_has_method(device->dev->handle, "_ADR"))
944 device->cap._ADR = 1;
945 if (acpi_has_method(device->dev->handle, "_BCL"))
946 device->cap._BCL = 1;
947 if (acpi_has_method(device->dev->handle, "_BCM"))
948 device->cap._BCM = 1;
949 if (acpi_has_method(device->dev->handle, "_BQC")) {
950 device->cap._BQC = 1;
951 } else if (acpi_has_method(device->dev->handle, "_BCQ")) {
952 printk(KERN_WARNING FW_BUG "_BCQ is used instead of _BQC\n");
953 device->cap._BCQ = 1;
954 }
955
956 if (acpi_has_method(device->dev->handle, "_DDC"))
957 device->cap._DDC = 1;
958 }
959
960 /*
961 * Arg:
962 * device : video output device (VGA)
963 *
964 * Return Value:
965 * None
966 *
967 * Find out all required AML methods defined under the video bus device.
968 */
969
970 static void acpi_video_bus_find_cap(struct acpi_video_bus *video)
971 {
972 if (acpi_has_method(video->device->handle, "_DOS"))
973 video->cap._DOS = 1;
974 if (acpi_has_method(video->device->handle, "_DOD"))
975 video->cap._DOD = 1;
976 if (acpi_has_method(video->device->handle, "_ROM"))
977 video->cap._ROM = 1;
978 if (acpi_has_method(video->device->handle, "_GPD"))
979 video->cap._GPD = 1;
980 if (acpi_has_method(video->device->handle, "_SPD"))
981 video->cap._SPD = 1;
982 if (acpi_has_method(video->device->handle, "_VPO"))
983 video->cap._VPO = 1;
984 }
985
986 /*
987 * Check whether the video bus device has required AML method to
988 * support the desired features
989 */
990
991 static int acpi_video_bus_check(struct acpi_video_bus *video)
992 {
993 acpi_status status = -ENOENT;
994 struct pci_dev *dev;
995
996 if (!video)
997 return -EINVAL;
998
999 dev = acpi_get_pci_dev(video->device->handle);
1000 if (!dev)
1001 return -ENODEV;
1002 pci_dev_put(dev);
1003
1004 /*
1005 * Since there is no HID, CID and so on for VGA driver, we have
1006 * to check well known required nodes.
1007 */
1008
1009 /* Does this device support video switching? */
1010 if (video->cap._DOS || video->cap._DOD) {
1011 if (!video->cap._DOS) {
1012 printk(KERN_WARNING FW_BUG
1013 "ACPI(%s) defines _DOD but not _DOS\n",
1014 acpi_device_bid(video->device));
1015 }
1016 video->flags.multihead = 1;
1017 status = 0;
1018 }
1019
1020 /* Does this device support retrieving a video ROM? */
1021 if (video->cap._ROM) {
1022 video->flags.rom = 1;
1023 status = 0;
1024 }
1025
1026 /* Does this device support configuring which video device to POST? */
1027 if (video->cap._GPD && video->cap._SPD && video->cap._VPO) {
1028 video->flags.post = 1;
1029 status = 0;
1030 }
1031
1032 return status;
1033 }
1034
1035 /*
1036 * --------------------------------------------------------------------------
1037 * Driver Interface
1038 * --------------------------------------------------------------------------
1039 */
1040
1041 /* device interface */
1042 static struct acpi_video_device_attrib *
1043 acpi_video_get_device_attr(struct acpi_video_bus *video, unsigned long device_id)
1044 {
1045 struct acpi_video_enumerated_device *ids;
1046 int i;
1047
1048 for (i = 0; i < video->attached_count; i++) {
1049 ids = &video->attached_array[i];
1050 if ((ids->value.int_val & 0xffff) == device_id)
1051 return &ids->value.attrib;
1052 }
1053
1054 return NULL;
1055 }
1056
1057 static int
1058 acpi_video_get_device_type(struct acpi_video_bus *video,
1059 unsigned long device_id)
1060 {
1061 struct acpi_video_enumerated_device *ids;
1062 int i;
1063
1064 for (i = 0; i < video->attached_count; i++) {
1065 ids = &video->attached_array[i];
1066 if ((ids->value.int_val & 0xffff) == device_id)
1067 return ids->value.int_val;
1068 }
1069
1070 return 0;
1071 }
1072
1073 static int
1074 acpi_video_bus_get_one_device(struct acpi_device *device,
1075 struct acpi_video_bus *video)
1076 {
1077 unsigned long long device_id;
1078 int status, device_type;
1079 struct acpi_video_device *data;
1080 struct acpi_video_device_attrib *attribute;
1081
1082 status =
1083 acpi_evaluate_integer(device->handle, "_ADR", NULL, &device_id);
1084 /* Some device omits _ADR, we skip them instead of fail */
1085 if (ACPI_FAILURE(status))
1086 return 0;
1087
1088 data = kzalloc(sizeof(struct acpi_video_device), GFP_KERNEL);
1089 if (!data)
1090 return -ENOMEM;
1091
1092 strcpy(acpi_device_name(device), ACPI_VIDEO_DEVICE_NAME);
1093 strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
1094 device->driver_data = data;
1095
1096 data->device_id = device_id;
1097 data->video = video;
1098 data->dev = device;
1099 INIT_DELAYED_WORK(&data->switch_brightness_work,
1100 acpi_video_switch_brightness);
1101
1102 attribute = acpi_video_get_device_attr(video, device_id);
1103
1104 if (attribute && (attribute->device_id_scheme || device_id_scheme)) {
1105 switch (attribute->display_type) {
1106 case ACPI_VIDEO_DISPLAY_CRT:
1107 data->flags.crt = 1;
1108 break;
1109 case ACPI_VIDEO_DISPLAY_TV:
1110 data->flags.tvout = 1;
1111 break;
1112 case ACPI_VIDEO_DISPLAY_DVI:
1113 data->flags.dvi = 1;
1114 break;
1115 case ACPI_VIDEO_DISPLAY_LCD:
1116 data->flags.lcd = 1;
1117 break;
1118 default:
1119 data->flags.unknown = 1;
1120 break;
1121 }
1122 if (attribute->bios_can_detect)
1123 data->flags.bios = 1;
1124 } else {
1125 /* Check for legacy IDs */
1126 device_type = acpi_video_get_device_type(video, device_id);
1127 /* Ignore bits 16 and 18-20 */
1128 switch (device_type & 0xffe2ffff) {
1129 case ACPI_VIDEO_DISPLAY_LEGACY_MONITOR:
1130 data->flags.crt = 1;
1131 break;
1132 case ACPI_VIDEO_DISPLAY_LEGACY_PANEL:
1133 data->flags.lcd = 1;
1134 break;
1135 case ACPI_VIDEO_DISPLAY_LEGACY_TV:
1136 data->flags.tvout = 1;
1137 break;
1138 default:
1139 data->flags.unknown = 1;
1140 }
1141 }
1142
1143 acpi_video_device_bind(video, data);
1144 acpi_video_device_find_cap(data);
1145
1146 mutex_lock(&video->device_list_lock);
1147 list_add_tail(&data->entry, &video->video_device_list);
1148 mutex_unlock(&video->device_list_lock);
1149
1150 return status;
1151 }
1152
1153 /*
1154 * Arg:
1155 * video : video bus device
1156 *
1157 * Return:
1158 * none
1159 *
1160 * Enumerate the video device list of the video bus,
1161 * bind the ids with the corresponding video devices
1162 * under the video bus.
1163 */
1164
1165 static void acpi_video_device_rebind(struct acpi_video_bus *video)
1166 {
1167 struct acpi_video_device *dev;
1168
1169 mutex_lock(&video->device_list_lock);
1170
1171 list_for_each_entry(dev, &video->video_device_list, entry)
1172 acpi_video_device_bind(video, dev);
1173
1174 mutex_unlock(&video->device_list_lock);
1175 }
1176
1177 /*
1178 * Arg:
1179 * video : video bus device
1180 * device : video output device under the video
1181 * bus
1182 *
1183 * Return:
1184 * none
1185 *
1186 * Bind the ids with the corresponding video devices
1187 * under the video bus.
1188 */
1189
1190 static void
1191 acpi_video_device_bind(struct acpi_video_bus *video,
1192 struct acpi_video_device *device)
1193 {
1194 struct acpi_video_enumerated_device *ids;
1195 int i;
1196
1197 for (i = 0; i < video->attached_count; i++) {
1198 ids = &video->attached_array[i];
1199 if (device->device_id == (ids->value.int_val & 0xffff)) {
1200 ids->bind_info = device;
1201 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "device_bind %d\n", i));
1202 }
1203 }
1204 }
1205
1206 static bool acpi_video_device_in_dod(struct acpi_video_device *device)
1207 {
1208 struct acpi_video_bus *video = device->video;
1209 int i;
1210
1211 /*
1212 * If we have a broken _DOD or we have more than 8 output devices
1213 * under the graphics controller node that we can't proper deal with
1214 * in the operation region code currently, no need to test.
1215 */
1216 if (!video->attached_count || video->child_count > 8)
1217 return true;
1218
1219 for (i = 0; i < video->attached_count; i++) {
1220 if ((video->attached_array[i].value.int_val & 0xfff) ==
1221 (device->device_id & 0xfff))
1222 return true;
1223 }
1224
1225 return false;
1226 }
1227
1228 /*
1229 * Arg:
1230 * video : video bus device
1231 *
1232 * Return:
1233 * < 0 : error
1234 *
1235 * Call _DOD to enumerate all devices attached to display adapter
1236 *
1237 */
1238
1239 static int acpi_video_device_enumerate(struct acpi_video_bus *video)
1240 {
1241 int status;
1242 int count;
1243 int i;
1244 struct acpi_video_enumerated_device *active_list;
1245 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1246 union acpi_object *dod = NULL;
1247 union acpi_object *obj;
1248
1249 if (!video->cap._DOD)
1250 return AE_NOT_EXIST;
1251
1252 status = acpi_evaluate_object(video->device->handle, "_DOD", NULL, &buffer);
1253 if (!ACPI_SUCCESS(status)) {
1254 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _DOD"));
1255 return status;
1256 }
1257
1258 dod = buffer.pointer;
1259 if (!dod || (dod->type != ACPI_TYPE_PACKAGE)) {
1260 ACPI_EXCEPTION((AE_INFO, status, "Invalid _DOD data"));
1261 status = -EFAULT;
1262 goto out;
1263 }
1264
1265 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d video heads in _DOD\n",
1266 dod->package.count));
1267
1268 active_list = kcalloc(1 + dod->package.count,
1269 sizeof(struct acpi_video_enumerated_device),
1270 GFP_KERNEL);
1271 if (!active_list) {
1272 status = -ENOMEM;
1273 goto out;
1274 }
1275
1276 count = 0;
1277 for (i = 0; i < dod->package.count; i++) {
1278 obj = &dod->package.elements[i];
1279
1280 if (obj->type != ACPI_TYPE_INTEGER) {
1281 printk(KERN_ERR PREFIX
1282 "Invalid _DOD data in element %d\n", i);
1283 continue;
1284 }
1285
1286 active_list[count].value.int_val = obj->integer.value;
1287 active_list[count].bind_info = NULL;
1288 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "dod element[%d] = %d\n", i,
1289 (int)obj->integer.value));
1290 count++;
1291 }
1292
1293 kfree(video->attached_array);
1294
1295 video->attached_array = active_list;
1296 video->attached_count = count;
1297
1298 out:
1299 kfree(buffer.pointer);
1300 return status;
1301 }
1302
1303 static int
1304 acpi_video_get_next_level(struct acpi_video_device *device,
1305 u32 level_current, u32 event)
1306 {
1307 int min, max, min_above, max_below, i, l, delta = 255;
1308 max = max_below = 0;
1309 min = min_above = 255;
1310 /* Find closest level to level_current */
1311 for (i = 2; i < device->brightness->count; i++) {
1312 l = device->brightness->levels[i];
1313 if (abs(l - level_current) < abs(delta)) {
1314 delta = l - level_current;
1315 if (!delta)
1316 break;
1317 }
1318 }
1319 /* Ajust level_current to closest available level */
1320 level_current += delta;
1321 for (i = 2; i < device->brightness->count; i++) {
1322 l = device->brightness->levels[i];
1323 if (l < min)
1324 min = l;
1325 if (l > max)
1326 max = l;
1327 if (l < min_above && l > level_current)
1328 min_above = l;
1329 if (l > max_below && l < level_current)
1330 max_below = l;
1331 }
1332
1333 switch (event) {
1334 case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:
1335 return (level_current < max) ? min_above : min;
1336 case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:
1337 return (level_current < max) ? min_above : max;
1338 case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:
1339 return (level_current > min) ? max_below : min;
1340 case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS:
1341 case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:
1342 return 0;
1343 default:
1344 return level_current;
1345 }
1346 }
1347
1348 static void
1349 acpi_video_switch_brightness(struct work_struct *work)
1350 {
1351 struct acpi_video_device *device = container_of(to_delayed_work(work),
1352 struct acpi_video_device, switch_brightness_work);
1353 unsigned long long level_current, level_next;
1354 int event = device->switch_brightness_event;
1355 int result = -EINVAL;
1356
1357 /* no warning message if acpi_backlight=vendor or a quirk is used */
1358 if (!device->backlight)
1359 return;
1360
1361 if (!device->brightness)
1362 goto out;
1363
1364 result = acpi_video_device_lcd_get_level_current(device,
1365 &level_current,
1366 false);
1367 if (result)
1368 goto out;
1369
1370 level_next = acpi_video_get_next_level(device, level_current, event);
1371
1372 result = acpi_video_device_lcd_set_level(device, level_next);
1373
1374 if (!result)
1375 backlight_force_update(device->backlight,
1376 BACKLIGHT_UPDATE_HOTKEY);
1377
1378 out:
1379 if (result)
1380 printk(KERN_ERR PREFIX "Failed to switch the brightness\n");
1381 }
1382
1383 int acpi_video_get_edid(struct acpi_device *device, int type, int device_id,
1384 void **edid)
1385 {
1386 struct acpi_video_bus *video;
1387 struct acpi_video_device *video_device;
1388 union acpi_object *buffer = NULL;
1389 acpi_status status;
1390 int i, length;
1391
1392 if (!device || !acpi_driver_data(device))
1393 return -EINVAL;
1394
1395 video = acpi_driver_data(device);
1396
1397 for (i = 0; i < video->attached_count; i++) {
1398 video_device = video->attached_array[i].bind_info;
1399 length = 256;
1400
1401 if (!video_device)
1402 continue;
1403
1404 if (!video_device->cap._DDC)
1405 continue;
1406
1407 if (type) {
1408 switch (type) {
1409 case ACPI_VIDEO_DISPLAY_CRT:
1410 if (!video_device->flags.crt)
1411 continue;
1412 break;
1413 case ACPI_VIDEO_DISPLAY_TV:
1414 if (!video_device->flags.tvout)
1415 continue;
1416 break;
1417 case ACPI_VIDEO_DISPLAY_DVI:
1418 if (!video_device->flags.dvi)
1419 continue;
1420 break;
1421 case ACPI_VIDEO_DISPLAY_LCD:
1422 if (!video_device->flags.lcd)
1423 continue;
1424 break;
1425 }
1426 } else if (video_device->device_id != device_id) {
1427 continue;
1428 }
1429
1430 status = acpi_video_device_EDID(video_device, &buffer, length);
1431
1432 if (ACPI_FAILURE(status) || !buffer ||
1433 buffer->type != ACPI_TYPE_BUFFER) {
1434 length = 128;
1435 status = acpi_video_device_EDID(video_device, &buffer,
1436 length);
1437 if (ACPI_FAILURE(status) || !buffer ||
1438 buffer->type != ACPI_TYPE_BUFFER) {
1439 continue;
1440 }
1441 }
1442
1443 *edid = buffer->buffer.pointer;
1444 return length;
1445 }
1446
1447 return -ENODEV;
1448 }
1449 EXPORT_SYMBOL(acpi_video_get_edid);
1450
1451 static int
1452 acpi_video_bus_get_devices(struct acpi_video_bus *video,
1453 struct acpi_device *device)
1454 {
1455 int status = 0;
1456 struct acpi_device *dev;
1457
1458 /*
1459 * There are systems where video module known to work fine regardless
1460 * of broken _DOD and ignoring returned value here doesn't cause
1461 * any issues later.
1462 */
1463 acpi_video_device_enumerate(video);
1464
1465 list_for_each_entry(dev, &device->children, node) {
1466
1467 status = acpi_video_bus_get_one_device(dev, video);
1468 if (status) {
1469 dev_err(&dev->dev, "Can't attach device\n");
1470 break;
1471 }
1472 video->child_count++;
1473 }
1474 return status;
1475 }
1476
1477 /* acpi_video interface */
1478
1479 /*
1480 * Win8 requires setting bit2 of _DOS to let firmware know it shouldn't
1481 * preform any automatic brightness change on receiving a notification.
1482 */
1483 static int acpi_video_bus_start_devices(struct acpi_video_bus *video)
1484 {
1485 return acpi_video_bus_DOS(video, 0,
1486 acpi_osi_is_win8() ? 1 : 0);
1487 }
1488
1489 static int acpi_video_bus_stop_devices(struct acpi_video_bus *video)
1490 {
1491 return acpi_video_bus_DOS(video, 0,
1492 acpi_osi_is_win8() ? 0 : 1);
1493 }
1494
1495 static void acpi_video_bus_notify(struct acpi_device *device, u32 event)
1496 {
1497 struct acpi_video_bus *video = acpi_driver_data(device);
1498 struct input_dev *input;
1499 int keycode = 0;
1500
1501 if (!video || !video->input)
1502 return;
1503
1504 input = video->input;
1505
1506 switch (event) {
1507 case ACPI_VIDEO_NOTIFY_SWITCH: /* User requested a switch,
1508 * most likely via hotkey. */
1509 keycode = KEY_SWITCHVIDEOMODE;
1510 break;
1511
1512 case ACPI_VIDEO_NOTIFY_PROBE: /* User plugged in or removed a video
1513 * connector. */
1514 acpi_video_device_enumerate(video);
1515 acpi_video_device_rebind(video);
1516 keycode = KEY_SWITCHVIDEOMODE;
1517 break;
1518
1519 case ACPI_VIDEO_NOTIFY_CYCLE: /* Cycle Display output hotkey pressed. */
1520 keycode = KEY_SWITCHVIDEOMODE;
1521 break;
1522 case ACPI_VIDEO_NOTIFY_NEXT_OUTPUT: /* Next Display output hotkey pressed. */
1523 keycode = KEY_VIDEO_NEXT;
1524 break;
1525 case ACPI_VIDEO_NOTIFY_PREV_OUTPUT: /* previous Display output hotkey pressed. */
1526 keycode = KEY_VIDEO_PREV;
1527 break;
1528
1529 default:
1530 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1531 "Unsupported event [0x%x]\n", event));
1532 break;
1533 }
1534
1535 if (acpi_notifier_call_chain(device, event, 0))
1536 /* Something vetoed the keypress. */
1537 keycode = 0;
1538
1539 if (keycode && (report_key_events & REPORT_OUTPUT_KEY_EVENTS)) {
1540 input_report_key(input, keycode, 1);
1541 input_sync(input);
1542 input_report_key(input, keycode, 0);
1543 input_sync(input);
1544 }
1545
1546 return;
1547 }
1548
1549 static void brightness_switch_event(struct acpi_video_device *video_device,
1550 u32 event)
1551 {
1552 if (!brightness_switch_enabled)
1553 return;
1554
1555 video_device->switch_brightness_event = event;
1556 schedule_delayed_work(&video_device->switch_brightness_work, HZ / 10);
1557 }
1558
1559 static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data)
1560 {
1561 struct acpi_video_device *video_device = data;
1562 struct acpi_device *device = NULL;
1563 struct acpi_video_bus *bus;
1564 struct input_dev *input;
1565 int keycode = 0;
1566
1567 if (!video_device)
1568 return;
1569
1570 device = video_device->dev;
1571 bus = video_device->video;
1572 input = bus->input;
1573
1574 switch (event) {
1575 case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS: /* Cycle brightness */
1576 brightness_switch_event(video_device, event);
1577 keycode = KEY_BRIGHTNESS_CYCLE;
1578 break;
1579 case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS: /* Increase brightness */
1580 brightness_switch_event(video_device, event);
1581 keycode = KEY_BRIGHTNESSUP;
1582 break;
1583 case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS: /* Decrease brightness */
1584 brightness_switch_event(video_device, event);
1585 keycode = KEY_BRIGHTNESSDOWN;
1586 break;
1587 case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS: /* zero brightness */
1588 brightness_switch_event(video_device, event);
1589 keycode = KEY_BRIGHTNESS_ZERO;
1590 break;
1591 case ACPI_VIDEO_NOTIFY_DISPLAY_OFF: /* display device off */
1592 brightness_switch_event(video_device, event);
1593 keycode = KEY_DISPLAY_OFF;
1594 break;
1595 default:
1596 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1597 "Unsupported event [0x%x]\n", event));
1598 break;
1599 }
1600
1601 acpi_notifier_call_chain(device, event, 0);
1602
1603 if (keycode && (report_key_events & REPORT_BRIGHTNESS_KEY_EVENTS)) {
1604 input_report_key(input, keycode, 1);
1605 input_sync(input);
1606 input_report_key(input, keycode, 0);
1607 input_sync(input);
1608 }
1609
1610 return;
1611 }
1612
1613 static int acpi_video_resume(struct notifier_block *nb,
1614 unsigned long val, void *ign)
1615 {
1616 struct acpi_video_bus *video;
1617 struct acpi_video_device *video_device;
1618 int i;
1619
1620 switch (val) {
1621 case PM_HIBERNATION_PREPARE:
1622 case PM_SUSPEND_PREPARE:
1623 case PM_RESTORE_PREPARE:
1624 return NOTIFY_DONE;
1625 }
1626
1627 video = container_of(nb, struct acpi_video_bus, pm_nb);
1628
1629 dev_info(&video->device->dev, "Restoring backlight state\n");
1630
1631 for (i = 0; i < video->attached_count; i++) {
1632 video_device = video->attached_array[i].bind_info;
1633 if (video_device && video_device->brightness)
1634 acpi_video_device_lcd_set_level(video_device,
1635 video_device->brightness->curr);
1636 }
1637
1638 return NOTIFY_OK;
1639 }
1640
1641 static acpi_status
1642 acpi_video_bus_match(acpi_handle handle, u32 level, void *context,
1643 void **return_value)
1644 {
1645 struct acpi_device *device = context;
1646 struct acpi_device *sibling;
1647 int result;
1648
1649 if (handle == device->handle)
1650 return AE_CTRL_TERMINATE;
1651
1652 result = acpi_bus_get_device(handle, &sibling);
1653 if (result)
1654 return AE_OK;
1655
1656 if (!strcmp(acpi_device_name(sibling), ACPI_VIDEO_BUS_NAME))
1657 return AE_ALREADY_EXISTS;
1658
1659 return AE_OK;
1660 }
1661
1662 static void acpi_video_dev_register_backlight(struct acpi_video_device *device)
1663 {
1664 struct backlight_properties props;
1665 struct pci_dev *pdev;
1666 acpi_handle acpi_parent;
1667 struct device *parent = NULL;
1668 int result;
1669 static int count;
1670 char *name;
1671
1672 result = acpi_video_init_brightness(device);
1673 if (result)
1674 return;
1675
1676 if (disable_backlight_sysfs_if > 0)
1677 return;
1678
1679 name = kasprintf(GFP_KERNEL, "acpi_video%d", count);
1680 if (!name)
1681 return;
1682 count++;
1683
1684 acpi_get_parent(device->dev->handle, &acpi_parent);
1685
1686 pdev = acpi_get_pci_dev(acpi_parent);
1687 if (pdev) {
1688 parent = &pdev->dev;
1689 pci_dev_put(pdev);
1690 }
1691
1692 memset(&props, 0, sizeof(struct backlight_properties));
1693 props.type = BACKLIGHT_FIRMWARE;
1694 props.max_brightness = device->brightness->count - 3;
1695 device->backlight = backlight_device_register(name,
1696 parent,
1697 device,
1698 &acpi_backlight_ops,
1699 &props);
1700 kfree(name);
1701 if (IS_ERR(device->backlight)) {
1702 device->backlight = NULL;
1703 return;
1704 }
1705
1706 /*
1707 * Save current brightness level in case we have to restore it
1708 * before acpi_video_device_lcd_set_level() is called next time.
1709 */
1710 device->backlight->props.brightness =
1711 acpi_video_get_brightness(device->backlight);
1712
1713 device->cooling_dev = thermal_cooling_device_register("LCD",
1714 device->dev, &video_cooling_ops);
1715 if (IS_ERR(device->cooling_dev)) {
1716 /*
1717 * Set cooling_dev to NULL so we don't crash trying to free it.
1718 * Also, why the hell we are returning early and not attempt to
1719 * register video output if cooling device registration failed?
1720 * -- dtor
1721 */
1722 device->cooling_dev = NULL;
1723 return;
1724 }
1725
1726 dev_info(&device->dev->dev, "registered as cooling_device%d\n",
1727 device->cooling_dev->id);
1728 result = sysfs_create_link(&device->dev->dev.kobj,
1729 &device->cooling_dev->device.kobj,
1730 "thermal_cooling");
1731 if (result)
1732 printk(KERN_ERR PREFIX "Create sysfs link\n");
1733 result = sysfs_create_link(&device->cooling_dev->device.kobj,
1734 &device->dev->dev.kobj, "device");
1735 if (result)
1736 printk(KERN_ERR PREFIX "Create sysfs link\n");
1737 }
1738
1739 static void acpi_video_run_bcl_for_osi(struct acpi_video_bus *video)
1740 {
1741 struct acpi_video_device *dev;
1742 union acpi_object *levels;
1743
1744 mutex_lock(&video->device_list_lock);
1745 list_for_each_entry(dev, &video->video_device_list, entry) {
1746 if (!acpi_video_device_lcd_query_levels(dev->dev->handle, &levels))
1747 kfree(levels);
1748 }
1749 mutex_unlock(&video->device_list_lock);
1750 }
1751
1752 static bool acpi_video_should_register_backlight(struct acpi_video_device *dev)
1753 {
1754 /*
1755 * Do not create backlight device for video output
1756 * device that is not in the enumerated list.
1757 */
1758 if (!acpi_video_device_in_dod(dev)) {
1759 dev_dbg(&dev->dev->dev, "not in _DOD list, ignore\n");
1760 return false;
1761 }
1762
1763 if (only_lcd)
1764 return dev->flags.lcd;
1765 return true;
1766 }
1767
1768 static int acpi_video_bus_register_backlight(struct acpi_video_bus *video)
1769 {
1770 struct acpi_video_device *dev;
1771
1772 if (video->backlight_registered)
1773 return 0;
1774
1775 acpi_video_run_bcl_for_osi(video);
1776
1777 if (acpi_video_get_backlight_type() != acpi_backlight_video)
1778 return 0;
1779
1780 mutex_lock(&video->device_list_lock);
1781 list_for_each_entry(dev, &video->video_device_list, entry) {
1782 if (acpi_video_should_register_backlight(dev))
1783 acpi_video_dev_register_backlight(dev);
1784 }
1785 mutex_unlock(&video->device_list_lock);
1786
1787 video->backlight_registered = true;
1788
1789 video->pm_nb.notifier_call = acpi_video_resume;
1790 video->pm_nb.priority = 0;
1791 return register_pm_notifier(&video->pm_nb);
1792 }
1793
1794 static void acpi_video_dev_unregister_backlight(struct acpi_video_device *device)
1795 {
1796 if (device->backlight) {
1797 backlight_device_unregister(device->backlight);
1798 device->backlight = NULL;
1799 }
1800 if (device->brightness) {
1801 kfree(device->brightness->levels);
1802 kfree(device->brightness);
1803 device->brightness = NULL;
1804 }
1805 if (device->cooling_dev) {
1806 sysfs_remove_link(&device->dev->dev.kobj, "thermal_cooling");
1807 sysfs_remove_link(&device->cooling_dev->device.kobj, "device");
1808 thermal_cooling_device_unregister(device->cooling_dev);
1809 device->cooling_dev = NULL;
1810 }
1811 }
1812
1813 static int acpi_video_bus_unregister_backlight(struct acpi_video_bus *video)
1814 {
1815 struct acpi_video_device *dev;
1816 int error;
1817
1818 if (!video->backlight_registered)
1819 return 0;
1820
1821 error = unregister_pm_notifier(&video->pm_nb);
1822
1823 mutex_lock(&video->device_list_lock);
1824 list_for_each_entry(dev, &video->video_device_list, entry)
1825 acpi_video_dev_unregister_backlight(dev);
1826 mutex_unlock(&video->device_list_lock);
1827
1828 video->backlight_registered = false;
1829
1830 return error;
1831 }
1832
1833 static void acpi_video_dev_add_notify_handler(struct acpi_video_device *device)
1834 {
1835 acpi_status status;
1836 struct acpi_device *adev = device->dev;
1837
1838 status = acpi_install_notify_handler(adev->handle, ACPI_DEVICE_NOTIFY,
1839 acpi_video_device_notify, device);
1840 if (ACPI_FAILURE(status))
1841 dev_err(&adev->dev, "Error installing notify handler\n");
1842 else
1843 device->flags.notify = 1;
1844 }
1845
1846 static int acpi_video_bus_add_notify_handler(struct acpi_video_bus *video)
1847 {
1848 struct input_dev *input;
1849 struct acpi_video_device *dev;
1850 int error;
1851
1852 video->input = input = input_allocate_device();
1853 if (!input) {
1854 error = -ENOMEM;
1855 goto out;
1856 }
1857
1858 error = acpi_video_bus_start_devices(video);
1859 if (error)
1860 goto err_free_input;
1861
1862 snprintf(video->phys, sizeof(video->phys),
1863 "%s/video/input0", acpi_device_hid(video->device));
1864
1865 input->name = acpi_device_name(video->device);
1866 input->phys = video->phys;
1867 input->id.bustype = BUS_HOST;
1868 input->id.product = 0x06;
1869 input->dev.parent = &video->device->dev;
1870 input->evbit[0] = BIT(EV_KEY);
1871 set_bit(KEY_SWITCHVIDEOMODE, input->keybit);
1872 set_bit(KEY_VIDEO_NEXT, input->keybit);
1873 set_bit(KEY_VIDEO_PREV, input->keybit);
1874 set_bit(KEY_BRIGHTNESS_CYCLE, input->keybit);
1875 set_bit(KEY_BRIGHTNESSUP, input->keybit);
1876 set_bit(KEY_BRIGHTNESSDOWN, input->keybit);
1877 set_bit(KEY_BRIGHTNESS_ZERO, input->keybit);
1878 set_bit(KEY_DISPLAY_OFF, input->keybit);
1879
1880 error = input_register_device(input);
1881 if (error)
1882 goto err_stop_dev;
1883
1884 mutex_lock(&video->device_list_lock);
1885 list_for_each_entry(dev, &video->video_device_list, entry)
1886 acpi_video_dev_add_notify_handler(dev);
1887 mutex_unlock(&video->device_list_lock);
1888
1889 return 0;
1890
1891 err_stop_dev:
1892 acpi_video_bus_stop_devices(video);
1893 err_free_input:
1894 input_free_device(input);
1895 video->input = NULL;
1896 out:
1897 return error;
1898 }
1899
1900 static void acpi_video_dev_remove_notify_handler(struct acpi_video_device *dev)
1901 {
1902 if (dev->flags.notify) {
1903 acpi_remove_notify_handler(dev->dev->handle, ACPI_DEVICE_NOTIFY,
1904 acpi_video_device_notify);
1905 dev->flags.notify = 0;
1906 }
1907 }
1908
1909 static void acpi_video_bus_remove_notify_handler(struct acpi_video_bus *video)
1910 {
1911 struct acpi_video_device *dev;
1912
1913 mutex_lock(&video->device_list_lock);
1914 list_for_each_entry(dev, &video->video_device_list, entry)
1915 acpi_video_dev_remove_notify_handler(dev);
1916 mutex_unlock(&video->device_list_lock);
1917
1918 acpi_video_bus_stop_devices(video);
1919 input_unregister_device(video->input);
1920 video->input = NULL;
1921 }
1922
1923 static int acpi_video_bus_put_devices(struct acpi_video_bus *video)
1924 {
1925 struct acpi_video_device *dev, *next;
1926
1927 mutex_lock(&video->device_list_lock);
1928 list_for_each_entry_safe(dev, next, &video->video_device_list, entry) {
1929 list_del(&dev->entry);
1930 kfree(dev);
1931 }
1932 mutex_unlock(&video->device_list_lock);
1933
1934 return 0;
1935 }
1936
1937 static int instance;
1938
1939 static int acpi_video_bus_add(struct acpi_device *device)
1940 {
1941 struct acpi_video_bus *video;
1942 int error;
1943 acpi_status status;
1944
1945 status = acpi_walk_namespace(ACPI_TYPE_DEVICE,
1946 device->parent->handle, 1,
1947 acpi_video_bus_match, NULL,
1948 device, NULL);
1949 if (status == AE_ALREADY_EXISTS) {
1950 printk(KERN_WARNING FW_BUG
1951 "Duplicate ACPI video bus devices for the"
1952 " same VGA controller, please try module "
1953 "parameter \"video.allow_duplicates=1\""
1954 "if the current driver doesn't work.\n");
1955 if (!allow_duplicates)
1956 return -ENODEV;
1957 }
1958
1959 video = kzalloc(sizeof(struct acpi_video_bus), GFP_KERNEL);
1960 if (!video)
1961 return -ENOMEM;
1962
1963 /* a hack to fix the duplicate name "VID" problem on T61 */
1964 if (!strcmp(device->pnp.bus_id, "VID")) {
1965 if (instance)
1966 device->pnp.bus_id[3] = '0' + instance;
1967 instance++;
1968 }
1969 /* a hack to fix the duplicate name "VGA" problem on Pa 3553 */
1970 if (!strcmp(device->pnp.bus_id, "VGA")) {
1971 if (instance)
1972 device->pnp.bus_id[3] = '0' + instance;
1973 instance++;
1974 }
1975
1976 video->device = device;
1977 strcpy(acpi_device_name(device), ACPI_VIDEO_BUS_NAME);
1978 strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
1979 device->driver_data = video;
1980
1981 acpi_video_bus_find_cap(video);
1982 error = acpi_video_bus_check(video);
1983 if (error)
1984 goto err_free_video;
1985
1986 mutex_init(&video->device_list_lock);
1987 INIT_LIST_HEAD(&video->video_device_list);
1988
1989 error = acpi_video_bus_get_devices(video, device);
1990 if (error)
1991 goto err_put_video;
1992
1993 printk(KERN_INFO PREFIX "%s [%s] (multi-head: %s rom: %s post: %s)\n",
1994 ACPI_VIDEO_DEVICE_NAME, acpi_device_bid(device),
1995 video->flags.multihead ? "yes" : "no",
1996 video->flags.rom ? "yes" : "no",
1997 video->flags.post ? "yes" : "no");
1998 mutex_lock(&video_list_lock);
1999 list_add_tail(&video->entry, &video_bus_head);
2000 mutex_unlock(&video_list_lock);
2001
2002 acpi_video_bus_register_backlight(video);
2003 acpi_video_bus_add_notify_handler(video);
2004
2005 return 0;
2006
2007 err_put_video:
2008 acpi_video_bus_put_devices(video);
2009 kfree(video->attached_array);
2010 err_free_video:
2011 kfree(video);
2012 device->driver_data = NULL;
2013
2014 return error;
2015 }
2016
2017 static int acpi_video_bus_remove(struct acpi_device *device)
2018 {
2019 struct acpi_video_bus *video = NULL;
2020
2021
2022 if (!device || !acpi_driver_data(device))
2023 return -EINVAL;
2024
2025 video = acpi_driver_data(device);
2026
2027 acpi_video_bus_remove_notify_handler(video);
2028 acpi_video_bus_unregister_backlight(video);
2029 acpi_video_bus_put_devices(video);
2030
2031 mutex_lock(&video_list_lock);
2032 list_del(&video->entry);
2033 mutex_unlock(&video_list_lock);
2034
2035 kfree(video->attached_array);
2036 kfree(video);
2037
2038 return 0;
2039 }
2040
2041 static int __init is_i740(struct pci_dev *dev)
2042 {
2043 if (dev->device == 0x00D1)
2044 return 1;
2045 if (dev->device == 0x7000)
2046 return 1;
2047 return 0;
2048 }
2049
2050 static int __init intel_opregion_present(void)
2051 {
2052 int opregion = 0;
2053 struct pci_dev *dev = NULL;
2054 u32 address;
2055
2056 for_each_pci_dev(dev) {
2057 if ((dev->class >> 8) != PCI_CLASS_DISPLAY_VGA)
2058 continue;
2059 if (dev->vendor != PCI_VENDOR_ID_INTEL)
2060 continue;
2061 /* We don't want to poke around undefined i740 registers */
2062 if (is_i740(dev))
2063 continue;
2064 pci_read_config_dword(dev, 0xfc, &address);
2065 if (!address)
2066 continue;
2067 opregion = 1;
2068 }
2069 return opregion;
2070 }
2071
2072 int acpi_video_register(void)
2073 {
2074 int ret = 0;
2075
2076 mutex_lock(&register_count_mutex);
2077 if (register_count) {
2078 /*
2079 * if the function of acpi_video_register is already called,
2080 * don't register the acpi_vide_bus again and return no error.
2081 */
2082 goto leave;
2083 }
2084
2085 dmi_check_system(video_dmi_table);
2086
2087 ret = acpi_bus_register_driver(&acpi_video_bus);
2088 if (ret)
2089 goto leave;
2090
2091 /*
2092 * When the acpi_video_bus is loaded successfully, increase
2093 * the counter reference.
2094 */
2095 register_count = 1;
2096
2097 leave:
2098 mutex_unlock(&register_count_mutex);
2099 return ret;
2100 }
2101 EXPORT_SYMBOL(acpi_video_register);
2102
2103 void acpi_video_unregister(void)
2104 {
2105 mutex_lock(&register_count_mutex);
2106 if (register_count) {
2107 acpi_bus_unregister_driver(&acpi_video_bus);
2108 register_count = 0;
2109 }
2110 mutex_unlock(&register_count_mutex);
2111 }
2112 EXPORT_SYMBOL(acpi_video_unregister);
2113
2114 void acpi_video_unregister_backlight(void)
2115 {
2116 struct acpi_video_bus *video;
2117
2118 mutex_lock(&register_count_mutex);
2119 if (register_count) {
2120 mutex_lock(&video_list_lock);
2121 list_for_each_entry(video, &video_bus_head, entry)
2122 acpi_video_bus_unregister_backlight(video);
2123 mutex_unlock(&video_list_lock);
2124 }
2125 mutex_unlock(&register_count_mutex);
2126 }
2127
2128 bool acpi_video_handles_brightness_key_presses(void)
2129 {
2130 bool have_video_busses;
2131
2132 mutex_lock(&video_list_lock);
2133 have_video_busses = !list_empty(&video_bus_head);
2134 mutex_unlock(&video_list_lock);
2135
2136 return have_video_busses &&
2137 (report_key_events & REPORT_BRIGHTNESS_KEY_EVENTS);
2138 }
2139 EXPORT_SYMBOL(acpi_video_handles_brightness_key_presses);
2140
2141 /*
2142 * This is kind of nasty. Hardware using Intel chipsets may require
2143 * the video opregion code to be run first in order to initialise
2144 * state before any ACPI video calls are made. To handle this we defer
2145 * registration of the video class until the opregion code has run.
2146 */
2147
2148 static int __init acpi_video_init(void)
2149 {
2150 /*
2151 * Let the module load even if ACPI is disabled (e.g. due to
2152 * a broken BIOS) so that i915.ko can still be loaded on such
2153 * old systems without an AcpiOpRegion.
2154 *
2155 * acpi_video_register() will report -ENODEV later as well due
2156 * to acpi_disabled when i915.ko tries to register itself afterwards.
2157 */
2158 if (acpi_disabled)
2159 return 0;
2160
2161 if (intel_opregion_present())
2162 return 0;
2163
2164 return acpi_video_register();
2165 }
2166
2167 static void __exit acpi_video_exit(void)
2168 {
2169 acpi_video_detect_exit();
2170 acpi_video_unregister();
2171
2172 return;
2173 }
2174
2175 module_init(acpi_video_init);
2176 module_exit(acpi_video_exit);
Linux with added FPC-III support