Loading...
Note: File does not exist in v3.1.
1/*
2 * video.c - ACPI Video Driver
3 *
4 * Copyright (C) 2004 Luming Yu <luming.yu@intel.com>
5 * Copyright (C) 2004 Bruno Ducrot <ducrot@poupinou.org>
6 * Copyright (C) 2006 Thomas Tuttle <linux-kernel@ttuttle.net>
7 *
8 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or (at
13 * your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful, but
16 * WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * General Public License for more details.
19 *
20 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
21 */
22
23#include <linux/kernel.h>
24#include <linux/module.h>
25#include <linux/init.h>
26#include <linux/types.h>
27#include <linux/list.h>
28#include <linux/mutex.h>
29#include <linux/input.h>
30#include <linux/backlight.h>
31#include <linux/thermal.h>
32#include <linux/sort.h>
33#include <linux/pci.h>
34#include <linux/pci_ids.h>
35#include <linux/slab.h>
36#include <linux/dmi.h>
37#include <linux/suspend.h>
38#include <linux/acpi.h>
39#include <acpi/video.h>
40#include <linux/uaccess.h>
41
42#define PREFIX "ACPI: "
43
44#define ACPI_VIDEO_BUS_NAME "Video Bus"
45#define ACPI_VIDEO_DEVICE_NAME "Video Device"
46
47#define MAX_NAME_LEN 20
48
49#define _COMPONENT ACPI_VIDEO_COMPONENT
50ACPI_MODULE_NAME("video");
51
52MODULE_AUTHOR("Bruno Ducrot");
53MODULE_DESCRIPTION("ACPI Video Driver");
54MODULE_LICENSE("GPL");
55
56static bool brightness_switch_enabled = true;
57module_param(brightness_switch_enabled, bool, 0644);
58
59/*
60 * By default, we don't allow duplicate ACPI video bus devices
61 * under the same VGA controller
62 */
63static bool allow_duplicates;
64module_param(allow_duplicates, bool, 0644);
65
66static int disable_backlight_sysfs_if = -1;
67module_param(disable_backlight_sysfs_if, int, 0444);
68
69#define REPORT_OUTPUT_KEY_EVENTS 0x01
70#define REPORT_BRIGHTNESS_KEY_EVENTS 0x02
71static int report_key_events = -1;
72module_param(report_key_events, int, 0644);
73MODULE_PARM_DESC(report_key_events,
74 "0: none, 1: output changes, 2: brightness changes, 3: all");
75
76/*
77 * Whether the struct acpi_video_device_attrib::device_id_scheme bit should be
78 * assumed even if not actually set.
79 */
80static bool device_id_scheme = false;
81module_param(device_id_scheme, bool, 0444);
82
83static int only_lcd = -1;
84module_param(only_lcd, int, 0444);
85
86static int register_count;
87static DEFINE_MUTEX(register_count_mutex);
88static DEFINE_MUTEX(video_list_lock);
89static LIST_HEAD(video_bus_head);
90static int acpi_video_bus_add(struct acpi_device *device);
91static int acpi_video_bus_remove(struct acpi_device *device);
92static void acpi_video_bus_notify(struct acpi_device *device, u32 event);
93void acpi_video_detect_exit(void);
94
95/*
96 * Indices in the _BCL method response: the first two items are special,
97 * the rest are all supported levels.
98 *
99 * See page 575 of the ACPI spec 3.0
100 */
101enum acpi_video_level_idx {
102 ACPI_VIDEO_AC_LEVEL, /* level when machine has full power */
103 ACPI_VIDEO_BATTERY_LEVEL, /* level when machine is on batteries */
104 ACPI_VIDEO_FIRST_LEVEL, /* actual supported levels begin here */
105};
106
107static const struct acpi_device_id video_device_ids[] = {
108 {ACPI_VIDEO_HID, 0},
109 {"", 0},
110};
111MODULE_DEVICE_TABLE(acpi, video_device_ids);
112
113static struct acpi_driver acpi_video_bus = {
114 .name = "video",
115 .class = ACPI_VIDEO_CLASS,
116 .ids = video_device_ids,
117 .ops = {
118 .add = acpi_video_bus_add,
119 .remove = acpi_video_bus_remove,
120 .notify = acpi_video_bus_notify,
121 },
122};
123
124struct acpi_video_bus_flags {
125 u8 multihead:1; /* can switch video heads */
126 u8 rom:1; /* can retrieve a video rom */
127 u8 post:1; /* can configure the head to */
128 u8 reserved:5;
129};
130
131struct acpi_video_bus_cap {
132 u8 _DOS:1; /* Enable/Disable output switching */
133 u8 _DOD:1; /* Enumerate all devices attached to display adapter */
134 u8 _ROM:1; /* Get ROM Data */
135 u8 _GPD:1; /* Get POST Device */
136 u8 _SPD:1; /* Set POST Device */
137 u8 _VPO:1; /* Video POST Options */
138 u8 reserved:2;
139};
140
141struct acpi_video_device_attrib {
142 u32 display_index:4; /* A zero-based instance of the Display */
143 u32 display_port_attachment:4; /* This field differentiates the display type */
144 u32 display_type:4; /* Describe the specific type in use */
145 u32 vendor_specific:4; /* Chipset Vendor Specific */
146 u32 bios_can_detect:1; /* BIOS can detect the device */
147 u32 depend_on_vga:1; /* Non-VGA output device whose power is related to
148 the VGA device. */
149 u32 pipe_id:3; /* For VGA multiple-head devices. */
150 u32 reserved:10; /* Must be 0 */
151
152 /*
153 * The device ID might not actually follow the scheme described by this
154 * struct acpi_video_device_attrib. If it does, then this bit
155 * device_id_scheme is set; otherwise, other fields should be ignored.
156 *
157 * (but also see the global flag device_id_scheme)
158 */
159 u32 device_id_scheme:1;
160};
161
162struct acpi_video_enumerated_device {
163 union {
164 u32 int_val;
165 struct acpi_video_device_attrib attrib;
166 } value;
167 struct acpi_video_device *bind_info;
168};
169
170struct acpi_video_bus {
171 struct acpi_device *device;
172 bool backlight_registered;
173 u8 dos_setting;
174 struct acpi_video_enumerated_device *attached_array;
175 u8 attached_count;
176 u8 child_count;
177 struct acpi_video_bus_cap cap;
178 struct acpi_video_bus_flags flags;
179 struct list_head video_device_list;
180 struct mutex device_list_lock; /* protects video_device_list */
181 struct list_head entry;
182 struct input_dev *input;
183 char phys[32]; /* for input device */
184 struct notifier_block pm_nb;
185};
186
187struct acpi_video_device_flags {
188 u8 crt:1;
189 u8 lcd:1;
190 u8 tvout:1;
191 u8 dvi:1;
192 u8 bios:1;
193 u8 unknown:1;
194 u8 notify:1;
195 u8 reserved:1;
196};
197
198struct acpi_video_device_cap {
199 u8 _ADR:1; /* Return the unique ID */
200 u8 _BCL:1; /* Query list of brightness control levels supported */
201 u8 _BCM:1; /* Set the brightness level */
202 u8 _BQC:1; /* Get current brightness level */
203 u8 _BCQ:1; /* Some buggy BIOS uses _BCQ instead of _BQC */
204 u8 _DDC:1; /* Return the EDID for this device */
205};
206
207struct acpi_video_device {
208 unsigned long device_id;
209 struct acpi_video_device_flags flags;
210 struct acpi_video_device_cap cap;
211 struct list_head entry;
212 struct delayed_work switch_brightness_work;
213 int switch_brightness_event;
214 struct acpi_video_bus *video;
215 struct acpi_device *dev;
216 struct acpi_video_device_brightness *brightness;
217 struct backlight_device *backlight;
218 struct thermal_cooling_device *cooling_dev;
219};
220
221static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data);
222static void acpi_video_device_rebind(struct acpi_video_bus *video);
223static void acpi_video_device_bind(struct acpi_video_bus *video,
224 struct acpi_video_device *device);
225static int acpi_video_device_enumerate(struct acpi_video_bus *video);
226static int acpi_video_device_lcd_set_level(struct acpi_video_device *device,
227 int level);
228static int acpi_video_device_lcd_get_level_current(
229 struct acpi_video_device *device,
230 unsigned long long *level, bool raw);
231static int acpi_video_get_next_level(struct acpi_video_device *device,
232 u32 level_current, u32 event);
233static void acpi_video_switch_brightness(struct work_struct *work);
234
235/* backlight device sysfs support */
236static int acpi_video_get_brightness(struct backlight_device *bd)
237{
238 unsigned long long cur_level;
239 int i;
240 struct acpi_video_device *vd = bl_get_data(bd);
241
242 if (acpi_video_device_lcd_get_level_current(vd, &cur_level, false))
243 return -EINVAL;
244 for (i = ACPI_VIDEO_FIRST_LEVEL; i < vd->brightness->count; i++) {
245 if (vd->brightness->levels[i] == cur_level)
246 return i - ACPI_VIDEO_FIRST_LEVEL;
247 }
248 return 0;
249}
250
251static int acpi_video_set_brightness(struct backlight_device *bd)
252{
253 int request_level = bd->props.brightness + ACPI_VIDEO_FIRST_LEVEL;
254 struct acpi_video_device *vd = bl_get_data(bd);
255
256 cancel_delayed_work(&vd->switch_brightness_work);
257 return acpi_video_device_lcd_set_level(vd,
258 vd->brightness->levels[request_level]);
259}
260
261static const struct backlight_ops acpi_backlight_ops = {
262 .get_brightness = acpi_video_get_brightness,
263 .update_status = acpi_video_set_brightness,
264};
265
266/* thermal cooling device callbacks */
267static int video_get_max_state(struct thermal_cooling_device *cooling_dev,
268 unsigned long *state)
269{
270 struct acpi_device *device = cooling_dev->devdata;
271 struct acpi_video_device *video = acpi_driver_data(device);
272
273 *state = video->brightness->count - ACPI_VIDEO_FIRST_LEVEL - 1;
274 return 0;
275}
276
277static int video_get_cur_state(struct thermal_cooling_device *cooling_dev,
278 unsigned long *state)
279{
280 struct acpi_device *device = cooling_dev->devdata;
281 struct acpi_video_device *video = acpi_driver_data(device);
282 unsigned long long level;
283 int offset;
284
285 if (acpi_video_device_lcd_get_level_current(video, &level, false))
286 return -EINVAL;
287 for (offset = ACPI_VIDEO_FIRST_LEVEL; offset < video->brightness->count;
288 offset++)
289 if (level == video->brightness->levels[offset]) {
290 *state = video->brightness->count - offset - 1;
291 return 0;
292 }
293
294 return -EINVAL;
295}
296
297static int
298video_set_cur_state(struct thermal_cooling_device *cooling_dev, unsigned long state)
299{
300 struct acpi_device *device = cooling_dev->devdata;
301 struct acpi_video_device *video = acpi_driver_data(device);
302 int level;
303
304 if (state >= video->brightness->count - ACPI_VIDEO_FIRST_LEVEL)
305 return -EINVAL;
306
307 state = video->brightness->count - state;
308 level = video->brightness->levels[state - 1];
309 return acpi_video_device_lcd_set_level(video, level);
310}
311
312static const struct thermal_cooling_device_ops video_cooling_ops = {
313 .get_max_state = video_get_max_state,
314 .get_cur_state = video_get_cur_state,
315 .set_cur_state = video_set_cur_state,
316};
317
318/*
319 * --------------------------------------------------------------------------
320 * Video Management
321 * --------------------------------------------------------------------------
322 */
323
324static int
325acpi_video_device_lcd_query_levels(acpi_handle handle,
326 union acpi_object **levels)
327{
328 int status;
329 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
330 union acpi_object *obj;
331
332
333 *levels = NULL;
334
335 status = acpi_evaluate_object(handle, "_BCL", NULL, &buffer);
336 if (!ACPI_SUCCESS(status))
337 return status;
338 obj = (union acpi_object *)buffer.pointer;
339 if (!obj || (obj->type != ACPI_TYPE_PACKAGE)) {
340 printk(KERN_ERR PREFIX "Invalid _BCL data\n");
341 status = -EFAULT;
342 goto err;
343 }
344
345 *levels = obj;
346
347 return 0;
348
349err:
350 kfree(buffer.pointer);
351
352 return status;
353}
354
355static int
356acpi_video_device_lcd_set_level(struct acpi_video_device *device, int level)
357{
358 int status;
359 int state;
360
361 status = acpi_execute_simple_method(device->dev->handle,
362 "_BCM", level);
363 if (ACPI_FAILURE(status)) {
364 ACPI_ERROR((AE_INFO, "Evaluating _BCM failed"));
365 return -EIO;
366 }
367
368 device->brightness->curr = level;
369 for (state = ACPI_VIDEO_FIRST_LEVEL; state < device->brightness->count;
370 state++)
371 if (level == device->brightness->levels[state]) {
372 if (device->backlight)
373 device->backlight->props.brightness =
374 state - ACPI_VIDEO_FIRST_LEVEL;
375 return 0;
376 }
377
378 ACPI_ERROR((AE_INFO, "Current brightness invalid"));
379 return -EINVAL;
380}
381
382/*
383 * For some buggy _BQC methods, we need to add a constant value to
384 * the _BQC return value to get the actual current brightness level
385 */
386
387static int bqc_offset_aml_bug_workaround;
388static int video_set_bqc_offset(const struct dmi_system_id *d)
389{
390 bqc_offset_aml_bug_workaround = 9;
391 return 0;
392}
393
394static int video_disable_backlight_sysfs_if(
395 const struct dmi_system_id *d)
396{
397 if (disable_backlight_sysfs_if == -1)
398 disable_backlight_sysfs_if = 1;
399 return 0;
400}
401
402static int video_set_device_id_scheme(const struct dmi_system_id *d)
403{
404 device_id_scheme = true;
405 return 0;
406}
407
408static int video_enable_only_lcd(const struct dmi_system_id *d)
409{
410 only_lcd = true;
411 return 0;
412}
413
414static int video_set_report_key_events(const struct dmi_system_id *id)
415{
416 if (report_key_events == -1)
417 report_key_events = (uintptr_t)id->driver_data;
418 return 0;
419}
420
421static const struct dmi_system_id video_dmi_table[] = {
422 /*
423 * Broken _BQC workaround http://bugzilla.kernel.org/show_bug.cgi?id=13121
424 */
425 {
426 .callback = video_set_bqc_offset,
427 .ident = "Acer Aspire 5720",
428 .matches = {
429 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
430 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5720"),
431 },
432 },
433 {
434 .callback = video_set_bqc_offset,
435 .ident = "Acer Aspire 5710Z",
436 .matches = {
437 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
438 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5710Z"),
439 },
440 },
441 {
442 .callback = video_set_bqc_offset,
443 .ident = "eMachines E510",
444 .matches = {
445 DMI_MATCH(DMI_BOARD_VENDOR, "EMACHINES"),
446 DMI_MATCH(DMI_PRODUCT_NAME, "eMachines E510"),
447 },
448 },
449 {
450 .callback = video_set_bqc_offset,
451 .ident = "Acer Aspire 5315",
452 .matches = {
453 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
454 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5315"),
455 },
456 },
457 {
458 .callback = video_set_bqc_offset,
459 .ident = "Acer Aspire 7720",
460 .matches = {
461 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
462 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 7720"),
463 },
464 },
465
466 /*
467 * Some machines have a broken acpi-video interface for brightness
468 * control, but still need an acpi_video_device_lcd_set_level() call
469 * on resume to turn the backlight power on. We Enable backlight
470 * control on these systems, but do not register a backlight sysfs
471 * as brightness control does not work.
472 */
473 {
474 /* https://bugzilla.kernel.org/show_bug.cgi?id=21012 */
475 .callback = video_disable_backlight_sysfs_if,
476 .ident = "Toshiba Portege R700",
477 .matches = {
478 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
479 DMI_MATCH(DMI_PRODUCT_NAME, "PORTEGE R700"),
480 },
481 },
482 {
483 /* https://bugs.freedesktop.org/show_bug.cgi?id=82634 */
484 .callback = video_disable_backlight_sysfs_if,
485 .ident = "Toshiba Portege R830",
486 .matches = {
487 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
488 DMI_MATCH(DMI_PRODUCT_NAME, "PORTEGE R830"),
489 },
490 },
491 {
492 /* https://bugzilla.kernel.org/show_bug.cgi?id=21012 */
493 .callback = video_disable_backlight_sysfs_if,
494 .ident = "Toshiba Satellite R830",
495 .matches = {
496 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
497 DMI_MATCH(DMI_PRODUCT_NAME, "SATELLITE R830"),
498 },
499 },
500 /*
501 * Some machine's _DOD IDs don't have bit 31(Device ID Scheme) set
502 * but the IDs actually follow the Device ID Scheme.
503 */
504 {
505 /* https://bugzilla.kernel.org/show_bug.cgi?id=104121 */
506 .callback = video_set_device_id_scheme,
507 .ident = "ESPRIMO Mobile M9410",
508 .matches = {
509 DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU SIEMENS"),
510 DMI_MATCH(DMI_PRODUCT_NAME, "ESPRIMO Mobile M9410"),
511 },
512 },
513 /*
514 * Some machines have multiple video output devices, but only the one
515 * that is the type of LCD can do the backlight control so we should not
516 * register backlight interface for other video output devices.
517 */
518 {
519 /* https://bugzilla.kernel.org/show_bug.cgi?id=104121 */
520 .callback = video_enable_only_lcd,
521 .ident = "ESPRIMO Mobile M9410",
522 .matches = {
523 DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU SIEMENS"),
524 DMI_MATCH(DMI_PRODUCT_NAME, "ESPRIMO Mobile M9410"),
525 },
526 },
527 /*
528 * Some machines report wrong key events on the acpi-bus, suppress
529 * key event reporting on these. Note this is only intended to work
530 * around events which are plain wrong. In some cases we get double
531 * events, in this case acpi-video is considered the canonical source
532 * and the events from the other source should be filtered. E.g.
533 * by calling acpi_video_handles_brightness_key_presses() from the
534 * vendor acpi/wmi driver or by using /lib/udev/hwdb.d/60-keyboard.hwdb
535 */
536 {
537 .callback = video_set_report_key_events,
538 .driver_data = (void *)((uintptr_t)REPORT_OUTPUT_KEY_EVENTS),
539 .ident = "Dell Vostro V131",
540 .matches = {
541 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
542 DMI_MATCH(DMI_PRODUCT_NAME, "Vostro V131"),
543 },
544 },
545 {}
546};
547
548static unsigned long long
549acpi_video_bqc_value_to_level(struct acpi_video_device *device,
550 unsigned long long bqc_value)
551{
552 unsigned long long level;
553
554 if (device->brightness->flags._BQC_use_index) {
555 /*
556 * _BQC returns an index that doesn't account for the first 2
557 * items with special meaning (see enum acpi_video_level_idx),
558 * so we need to compensate for that by offsetting ourselves
559 */
560 if (device->brightness->flags._BCL_reversed)
561 bqc_value = device->brightness->count -
562 ACPI_VIDEO_FIRST_LEVEL - 1 - bqc_value;
563
564 level = device->brightness->levels[bqc_value +
565 ACPI_VIDEO_FIRST_LEVEL];
566 } else {
567 level = bqc_value;
568 }
569
570 level += bqc_offset_aml_bug_workaround;
571
572 return level;
573}
574
575static int
576acpi_video_device_lcd_get_level_current(struct acpi_video_device *device,
577 unsigned long long *level, bool raw)
578{
579 acpi_status status = AE_OK;
580 int i;
581
582 if (device->cap._BQC || device->cap._BCQ) {
583 char *buf = device->cap._BQC ? "_BQC" : "_BCQ";
584
585 status = acpi_evaluate_integer(device->dev->handle, buf,
586 NULL, level);
587 if (ACPI_SUCCESS(status)) {
588 if (raw) {
589 /*
590 * Caller has indicated he wants the raw
591 * value returned by _BQC, so don't furtherly
592 * mess with the value.
593 */
594 return 0;
595 }
596
597 *level = acpi_video_bqc_value_to_level(device, *level);
598
599 for (i = ACPI_VIDEO_FIRST_LEVEL;
600 i < device->brightness->count; i++)
601 if (device->brightness->levels[i] == *level) {
602 device->brightness->curr = *level;
603 return 0;
604 }
605 /*
606 * BQC returned an invalid level.
607 * Stop using it.
608 */
609 ACPI_WARNING((AE_INFO,
610 "%s returned an invalid level",
611 buf));
612 device->cap._BQC = device->cap._BCQ = 0;
613 } else {
614 /*
615 * Fixme:
616 * should we return an error or ignore this failure?
617 * dev->brightness->curr is a cached value which stores
618 * the correct current backlight level in most cases.
619 * ACPI video backlight still works w/ buggy _BQC.
620 * http://bugzilla.kernel.org/show_bug.cgi?id=12233
621 */
622 ACPI_WARNING((AE_INFO, "Evaluating %s failed", buf));
623 device->cap._BQC = device->cap._BCQ = 0;
624 }
625 }
626
627 *level = device->brightness->curr;
628 return 0;
629}
630
631static int
632acpi_video_device_EDID(struct acpi_video_device *device,
633 union acpi_object **edid, ssize_t length)
634{
635 int status;
636 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
637 union acpi_object *obj;
638 union acpi_object arg0 = { ACPI_TYPE_INTEGER };
639 struct acpi_object_list args = { 1, &arg0 };
640
641
642 *edid = NULL;
643
644 if (!device)
645 return -ENODEV;
646 if (length == 128)
647 arg0.integer.value = 1;
648 else if (length == 256)
649 arg0.integer.value = 2;
650 else
651 return -EINVAL;
652
653 status = acpi_evaluate_object(device->dev->handle, "_DDC", &args, &buffer);
654 if (ACPI_FAILURE(status))
655 return -ENODEV;
656
657 obj = buffer.pointer;
658
659 if (obj && obj->type == ACPI_TYPE_BUFFER)
660 *edid = obj;
661 else {
662 printk(KERN_ERR PREFIX "Invalid _DDC data\n");
663 status = -EFAULT;
664 kfree(obj);
665 }
666
667 return status;
668}
669
670/* bus */
671
672/*
673 * Arg:
674 * video : video bus device pointer
675 * bios_flag :
676 * 0. The system BIOS should NOT automatically switch(toggle)
677 * the active display output.
678 * 1. The system BIOS should automatically switch (toggle) the
679 * active display output. No switch event.
680 * 2. The _DGS value should be locked.
681 * 3. The system BIOS should not automatically switch (toggle) the
682 * active display output, but instead generate the display switch
683 * event notify code.
684 * lcd_flag :
685 * 0. The system BIOS should automatically control the brightness level
686 * of the LCD when the power changes from AC to DC
687 * 1. The system BIOS should NOT automatically control the brightness
688 * level of the LCD when the power changes from AC to DC.
689 * Return Value:
690 * -EINVAL wrong arg.
691 */
692
693static int
694acpi_video_bus_DOS(struct acpi_video_bus *video, int bios_flag, int lcd_flag)
695{
696 acpi_status status;
697
698 if (!video->cap._DOS)
699 return 0;
700
701 if (bios_flag < 0 || bios_flag > 3 || lcd_flag < 0 || lcd_flag > 1)
702 return -EINVAL;
703 video->dos_setting = (lcd_flag << 2) | bios_flag;
704 status = acpi_execute_simple_method(video->device->handle, "_DOS",
705 (lcd_flag << 2) | bios_flag);
706 if (ACPI_FAILURE(status))
707 return -EIO;
708
709 return 0;
710}
711
712/*
713 * Simple comparison function used to sort backlight levels.
714 */
715
716static int
717acpi_video_cmp_level(const void *a, const void *b)
718{
719 return *(int *)a - *(int *)b;
720}
721
722/*
723 * Decides if _BQC/_BCQ for this system is usable
724 *
725 * We do this by changing the level first and then read out the current
726 * brightness level, if the value does not match, find out if it is using
727 * index. If not, clear the _BQC/_BCQ capability.
728 */
729static int acpi_video_bqc_quirk(struct acpi_video_device *device,
730 int max_level, int current_level)
731{
732 struct acpi_video_device_brightness *br = device->brightness;
733 int result;
734 unsigned long long level;
735 int test_level;
736
737 /* don't mess with existing known broken systems */
738 if (bqc_offset_aml_bug_workaround)
739 return 0;
740
741 /*
742 * Some systems always report current brightness level as maximum
743 * through _BQC, we need to test another value for them. However,
744 * there is a subtlety:
745 *
746 * If the _BCL package ordering is descending, the first level
747 * (br->levels[2]) is likely to be 0, and if the number of levels
748 * matches the number of steps, we might confuse a returned level to
749 * mean the index.
750 *
751 * For example:
752 *
753 * current_level = max_level = 100
754 * test_level = 0
755 * returned level = 100
756 *
757 * In this case 100 means the level, not the index, and _BCM failed.
758 * Still, if the _BCL package ordering is descending, the index of
759 * level 0 is also 100, so we assume _BQC is indexed, when it's not.
760 *
761 * This causes all _BQC calls to return bogus values causing weird
762 * behavior from the user's perspective. For example:
763 *
764 * xbacklight -set 10; xbacklight -set 20;
765 *
766 * would flash to 90% and then slowly down to the desired level (20).
767 *
768 * The solution is simple; test anything other than the first level
769 * (e.g. 1).
770 */
771 test_level = current_level == max_level
772 ? br->levels[ACPI_VIDEO_FIRST_LEVEL + 1]
773 : max_level;
774
775 result = acpi_video_device_lcd_set_level(device, test_level);
776 if (result)
777 return result;
778
779 result = acpi_video_device_lcd_get_level_current(device, &level, true);
780 if (result)
781 return result;
782
783 if (level != test_level) {
784 /* buggy _BQC found, need to find out if it uses index */
785 if (level < br->count) {
786 if (br->flags._BCL_reversed)
787 level = br->count - ACPI_VIDEO_FIRST_LEVEL - 1 - level;
788 if (br->levels[level + ACPI_VIDEO_FIRST_LEVEL] == test_level)
789 br->flags._BQC_use_index = 1;
790 }
791
792 if (!br->flags._BQC_use_index)
793 device->cap._BQC = device->cap._BCQ = 0;
794 }
795
796 return 0;
797}
798
799int acpi_video_get_levels(struct acpi_device *device,
800 struct acpi_video_device_brightness **dev_br,
801 int *pmax_level)
802{
803 union acpi_object *obj = NULL;
804 int i, max_level = 0, count = 0, level_ac_battery = 0;
805 union acpi_object *o;
806 struct acpi_video_device_brightness *br = NULL;
807 int result = 0;
808 u32 value;
809
810 if (!ACPI_SUCCESS(acpi_video_device_lcd_query_levels(device->handle,
811 &obj))) {
812 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Could not query available "
813 "LCD brightness level\n"));
814 result = -ENODEV;
815 goto out;
816 }
817
818 if (obj->package.count < ACPI_VIDEO_FIRST_LEVEL) {
819 result = -EINVAL;
820 goto out;
821 }
822
823 br = kzalloc(sizeof(*br), GFP_KERNEL);
824 if (!br) {
825 printk(KERN_ERR "can't allocate memory\n");
826 result = -ENOMEM;
827 goto out;
828 }
829
830 /*
831 * Note that we have to reserve 2 extra items (ACPI_VIDEO_FIRST_LEVEL),
832 * in order to account for buggy BIOS which don't export the first two
833 * special levels (see below)
834 */
835 br->levels = kmalloc((obj->package.count + ACPI_VIDEO_FIRST_LEVEL) *
836 sizeof(*br->levels), GFP_KERNEL);
837 if (!br->levels) {
838 result = -ENOMEM;
839 goto out_free;
840 }
841
842 for (i = 0; i < obj->package.count; i++) {
843 o = (union acpi_object *)&obj->package.elements[i];
844 if (o->type != ACPI_TYPE_INTEGER) {
845 printk(KERN_ERR PREFIX "Invalid data\n");
846 continue;
847 }
848 value = (u32) o->integer.value;
849 /* Skip duplicate entries */
850 if (count > ACPI_VIDEO_FIRST_LEVEL
851 && br->levels[count - 1] == value)
852 continue;
853
854 br->levels[count] = value;
855
856 if (br->levels[count] > max_level)
857 max_level = br->levels[count];
858 count++;
859 }
860
861 /*
862 * some buggy BIOS don't export the levels
863 * when machine is on AC/Battery in _BCL package.
864 * In this case, the first two elements in _BCL packages
865 * are also supported brightness levels that OS should take care of.
866 */
867 for (i = ACPI_VIDEO_FIRST_LEVEL; i < count; i++) {
868 if (br->levels[i] == br->levels[ACPI_VIDEO_AC_LEVEL])
869 level_ac_battery++;
870 if (br->levels[i] == br->levels[ACPI_VIDEO_BATTERY_LEVEL])
871 level_ac_battery++;
872 }
873
874 if (level_ac_battery < ACPI_VIDEO_FIRST_LEVEL) {
875 level_ac_battery = ACPI_VIDEO_FIRST_LEVEL - level_ac_battery;
876 br->flags._BCL_no_ac_battery_levels = 1;
877 for (i = (count - 1 + level_ac_battery);
878 i >= ACPI_VIDEO_FIRST_LEVEL; i--)
879 br->levels[i] = br->levels[i - level_ac_battery];
880 count += level_ac_battery;
881 } else if (level_ac_battery > ACPI_VIDEO_FIRST_LEVEL)
882 ACPI_ERROR((AE_INFO, "Too many duplicates in _BCL package"));
883
884 /* Check if the _BCL package is in a reversed order */
885 if (max_level == br->levels[ACPI_VIDEO_FIRST_LEVEL]) {
886 br->flags._BCL_reversed = 1;
887 sort(&br->levels[ACPI_VIDEO_FIRST_LEVEL],
888 count - ACPI_VIDEO_FIRST_LEVEL,
889 sizeof(br->levels[ACPI_VIDEO_FIRST_LEVEL]),
890 acpi_video_cmp_level, NULL);
891 } else if (max_level != br->levels[count - 1])
892 ACPI_ERROR((AE_INFO,
893 "Found unordered _BCL package"));
894
895 br->count = count;
896 *dev_br = br;
897 if (pmax_level)
898 *pmax_level = max_level;
899
900out:
901 kfree(obj);
902 return result;
903out_free:
904 kfree(br);
905 goto out;
906}
907EXPORT_SYMBOL(acpi_video_get_levels);
908
909/*
910 * Arg:
911 * device : video output device (LCD, CRT, ..)
912 *
913 * Return Value:
914 * Maximum brightness level
915 *
916 * Allocate and initialize device->brightness.
917 */
918
919static int
920acpi_video_init_brightness(struct acpi_video_device *device)
921{
922 int i, max_level = 0;
923 unsigned long long level, level_old;
924 struct acpi_video_device_brightness *br = NULL;
925 int result = -EINVAL;
926
927 result = acpi_video_get_levels(device->dev, &br, &max_level);
928 if (result)
929 return result;
930 device->brightness = br;
931
932 /* _BQC uses INDEX while _BCL uses VALUE in some laptops */
933 br->curr = level = max_level;
934
935 if (!device->cap._BQC)
936 goto set_level;
937
938 result = acpi_video_device_lcd_get_level_current(device,
939 &level_old, true);
940 if (result)
941 goto out_free_levels;
942
943 result = acpi_video_bqc_quirk(device, max_level, level_old);
944 if (result)
945 goto out_free_levels;
946 /*
947 * cap._BQC may get cleared due to _BQC is found to be broken
948 * in acpi_video_bqc_quirk, so check again here.
949 */
950 if (!device->cap._BQC)
951 goto set_level;
952
953 level = acpi_video_bqc_value_to_level(device, level_old);
954 /*
955 * On some buggy laptops, _BQC returns an uninitialized
956 * value when invoked for the first time, i.e.
957 * level_old is invalid (no matter whether it's a level
958 * or an index). Set the backlight to max_level in this case.
959 */
960 for (i = ACPI_VIDEO_FIRST_LEVEL; i < br->count; i++)
961 if (level == br->levels[i])
962 break;
963 if (i == br->count || !level)
964 level = max_level;
965
966set_level:
967 result = acpi_video_device_lcd_set_level(device, level);
968 if (result)
969 goto out_free_levels;
970
971 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
972 "found %d brightness levels\n",
973 br->count - ACPI_VIDEO_FIRST_LEVEL));
974 return 0;
975
976out_free_levels:
977 kfree(br->levels);
978 kfree(br);
979 device->brightness = NULL;
980 return result;
981}
982
983/*
984 * Arg:
985 * device : video output device (LCD, CRT, ..)
986 *
987 * Return Value:
988 * None
989 *
990 * Find out all required AML methods defined under the output
991 * device.
992 */
993
994static void acpi_video_device_find_cap(struct acpi_video_device *device)
995{
996 if (acpi_has_method(device->dev->handle, "_ADR"))
997 device->cap._ADR = 1;
998 if (acpi_has_method(device->dev->handle, "_BCL"))
999 device->cap._BCL = 1;
1000 if (acpi_has_method(device->dev->handle, "_BCM"))
1001 device->cap._BCM = 1;
1002 if (acpi_has_method(device->dev->handle, "_BQC")) {
1003 device->cap._BQC = 1;
1004 } else if (acpi_has_method(device->dev->handle, "_BCQ")) {
1005 printk(KERN_WARNING FW_BUG "_BCQ is used instead of _BQC\n");
1006 device->cap._BCQ = 1;
1007 }
1008
1009 if (acpi_has_method(device->dev->handle, "_DDC"))
1010 device->cap._DDC = 1;
1011}
1012
1013/*
1014 * Arg:
1015 * device : video output device (VGA)
1016 *
1017 * Return Value:
1018 * None
1019 *
1020 * Find out all required AML methods defined under the video bus device.
1021 */
1022
1023static void acpi_video_bus_find_cap(struct acpi_video_bus *video)
1024{
1025 if (acpi_has_method(video->device->handle, "_DOS"))
1026 video->cap._DOS = 1;
1027 if (acpi_has_method(video->device->handle, "_DOD"))
1028 video->cap._DOD = 1;
1029 if (acpi_has_method(video->device->handle, "_ROM"))
1030 video->cap._ROM = 1;
1031 if (acpi_has_method(video->device->handle, "_GPD"))
1032 video->cap._GPD = 1;
1033 if (acpi_has_method(video->device->handle, "_SPD"))
1034 video->cap._SPD = 1;
1035 if (acpi_has_method(video->device->handle, "_VPO"))
1036 video->cap._VPO = 1;
1037}
1038
1039/*
1040 * Check whether the video bus device has required AML method to
1041 * support the desired features
1042 */
1043
1044static int acpi_video_bus_check(struct acpi_video_bus *video)
1045{
1046 acpi_status status = -ENOENT;
1047 struct pci_dev *dev;
1048
1049 if (!video)
1050 return -EINVAL;
1051
1052 dev = acpi_get_pci_dev(video->device->handle);
1053 if (!dev)
1054 return -ENODEV;
1055 pci_dev_put(dev);
1056
1057 /*
1058 * Since there is no HID, CID and so on for VGA driver, we have
1059 * to check well known required nodes.
1060 */
1061
1062 /* Does this device support video switching? */
1063 if (video->cap._DOS || video->cap._DOD) {
1064 if (!video->cap._DOS) {
1065 printk(KERN_WARNING FW_BUG
1066 "ACPI(%s) defines _DOD but not _DOS\n",
1067 acpi_device_bid(video->device));
1068 }
1069 video->flags.multihead = 1;
1070 status = 0;
1071 }
1072
1073 /* Does this device support retrieving a video ROM? */
1074 if (video->cap._ROM) {
1075 video->flags.rom = 1;
1076 status = 0;
1077 }
1078
1079 /* Does this device support configuring which video device to POST? */
1080 if (video->cap._GPD && video->cap._SPD && video->cap._VPO) {
1081 video->flags.post = 1;
1082 status = 0;
1083 }
1084
1085 return status;
1086}
1087
1088/*
1089 * --------------------------------------------------------------------------
1090 * Driver Interface
1091 * --------------------------------------------------------------------------
1092 */
1093
1094/* device interface */
1095static struct acpi_video_device_attrib *
1096acpi_video_get_device_attr(struct acpi_video_bus *video, unsigned long device_id)
1097{
1098 struct acpi_video_enumerated_device *ids;
1099 int i;
1100
1101 for (i = 0; i < video->attached_count; i++) {
1102 ids = &video->attached_array[i];
1103 if ((ids->value.int_val & 0xffff) == device_id)
1104 return &ids->value.attrib;
1105 }
1106
1107 return NULL;
1108}
1109
1110static int
1111acpi_video_get_device_type(struct acpi_video_bus *video,
1112 unsigned long device_id)
1113{
1114 struct acpi_video_enumerated_device *ids;
1115 int i;
1116
1117 for (i = 0; i < video->attached_count; i++) {
1118 ids = &video->attached_array[i];
1119 if ((ids->value.int_val & 0xffff) == device_id)
1120 return ids->value.int_val;
1121 }
1122
1123 return 0;
1124}
1125
1126static int
1127acpi_video_bus_get_one_device(struct acpi_device *device,
1128 struct acpi_video_bus *video)
1129{
1130 unsigned long long device_id;
1131 int status, device_type;
1132 struct acpi_video_device *data;
1133 struct acpi_video_device_attrib *attribute;
1134
1135 status =
1136 acpi_evaluate_integer(device->handle, "_ADR", NULL, &device_id);
1137 /* Some device omits _ADR, we skip them instead of fail */
1138 if (ACPI_FAILURE(status))
1139 return 0;
1140
1141 data = kzalloc(sizeof(struct acpi_video_device), GFP_KERNEL);
1142 if (!data)
1143 return -ENOMEM;
1144
1145 strcpy(acpi_device_name(device), ACPI_VIDEO_DEVICE_NAME);
1146 strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
1147 device->driver_data = data;
1148
1149 data->device_id = device_id;
1150 data->video = video;
1151 data->dev = device;
1152 INIT_DELAYED_WORK(&data->switch_brightness_work,
1153 acpi_video_switch_brightness);
1154
1155 attribute = acpi_video_get_device_attr(video, device_id);
1156
1157 if (attribute && (attribute->device_id_scheme || device_id_scheme)) {
1158 switch (attribute->display_type) {
1159 case ACPI_VIDEO_DISPLAY_CRT:
1160 data->flags.crt = 1;
1161 break;
1162 case ACPI_VIDEO_DISPLAY_TV:
1163 data->flags.tvout = 1;
1164 break;
1165 case ACPI_VIDEO_DISPLAY_DVI:
1166 data->flags.dvi = 1;
1167 break;
1168 case ACPI_VIDEO_DISPLAY_LCD:
1169 data->flags.lcd = 1;
1170 break;
1171 default:
1172 data->flags.unknown = 1;
1173 break;
1174 }
1175 if (attribute->bios_can_detect)
1176 data->flags.bios = 1;
1177 } else {
1178 /* Check for legacy IDs */
1179 device_type = acpi_video_get_device_type(video, device_id);
1180 /* Ignore bits 16 and 18-20 */
1181 switch (device_type & 0xffe2ffff) {
1182 case ACPI_VIDEO_DISPLAY_LEGACY_MONITOR:
1183 data->flags.crt = 1;
1184 break;
1185 case ACPI_VIDEO_DISPLAY_LEGACY_PANEL:
1186 data->flags.lcd = 1;
1187 break;
1188 case ACPI_VIDEO_DISPLAY_LEGACY_TV:
1189 data->flags.tvout = 1;
1190 break;
1191 default:
1192 data->flags.unknown = 1;
1193 }
1194 }
1195
1196 acpi_video_device_bind(video, data);
1197 acpi_video_device_find_cap(data);
1198
1199 mutex_lock(&video->device_list_lock);
1200 list_add_tail(&data->entry, &video->video_device_list);
1201 mutex_unlock(&video->device_list_lock);
1202
1203 return status;
1204}
1205
1206/*
1207 * Arg:
1208 * video : video bus device
1209 *
1210 * Return:
1211 * none
1212 *
1213 * Enumerate the video device list of the video bus,
1214 * bind the ids with the corresponding video devices
1215 * under the video bus.
1216 */
1217
1218static void acpi_video_device_rebind(struct acpi_video_bus *video)
1219{
1220 struct acpi_video_device *dev;
1221
1222 mutex_lock(&video->device_list_lock);
1223
1224 list_for_each_entry(dev, &video->video_device_list, entry)
1225 acpi_video_device_bind(video, dev);
1226
1227 mutex_unlock(&video->device_list_lock);
1228}
1229
1230/*
1231 * Arg:
1232 * video : video bus device
1233 * device : video output device under the video
1234 * bus
1235 *
1236 * Return:
1237 * none
1238 *
1239 * Bind the ids with the corresponding video devices
1240 * under the video bus.
1241 */
1242
1243static void
1244acpi_video_device_bind(struct acpi_video_bus *video,
1245 struct acpi_video_device *device)
1246{
1247 struct acpi_video_enumerated_device *ids;
1248 int i;
1249
1250 for (i = 0; i < video->attached_count; i++) {
1251 ids = &video->attached_array[i];
1252 if (device->device_id == (ids->value.int_val & 0xffff)) {
1253 ids->bind_info = device;
1254 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "device_bind %d\n", i));
1255 }
1256 }
1257}
1258
1259static bool acpi_video_device_in_dod(struct acpi_video_device *device)
1260{
1261 struct acpi_video_bus *video = device->video;
1262 int i;
1263
1264 /*
1265 * If we have a broken _DOD or we have more than 8 output devices
1266 * under the graphics controller node that we can't proper deal with
1267 * in the operation region code currently, no need to test.
1268 */
1269 if (!video->attached_count || video->child_count > 8)
1270 return true;
1271
1272 for (i = 0; i < video->attached_count; i++) {
1273 if ((video->attached_array[i].value.int_val & 0xfff) ==
1274 (device->device_id & 0xfff))
1275 return true;
1276 }
1277
1278 return false;
1279}
1280
1281/*
1282 * Arg:
1283 * video : video bus device
1284 *
1285 * Return:
1286 * < 0 : error
1287 *
1288 * Call _DOD to enumerate all devices attached to display adapter
1289 *
1290 */
1291
1292static int acpi_video_device_enumerate(struct acpi_video_bus *video)
1293{
1294 int status;
1295 int count;
1296 int i;
1297 struct acpi_video_enumerated_device *active_list;
1298 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1299 union acpi_object *dod = NULL;
1300 union acpi_object *obj;
1301
1302 if (!video->cap._DOD)
1303 return AE_NOT_EXIST;
1304
1305 status = acpi_evaluate_object(video->device->handle, "_DOD", NULL, &buffer);
1306 if (!ACPI_SUCCESS(status)) {
1307 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _DOD"));
1308 return status;
1309 }
1310
1311 dod = buffer.pointer;
1312 if (!dod || (dod->type != ACPI_TYPE_PACKAGE)) {
1313 ACPI_EXCEPTION((AE_INFO, status, "Invalid _DOD data"));
1314 status = -EFAULT;
1315 goto out;
1316 }
1317
1318 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d video heads in _DOD\n",
1319 dod->package.count));
1320
1321 active_list = kcalloc(1 + dod->package.count,
1322 sizeof(struct acpi_video_enumerated_device),
1323 GFP_KERNEL);
1324 if (!active_list) {
1325 status = -ENOMEM;
1326 goto out;
1327 }
1328
1329 count = 0;
1330 for (i = 0; i < dod->package.count; i++) {
1331 obj = &dod->package.elements[i];
1332
1333 if (obj->type != ACPI_TYPE_INTEGER) {
1334 printk(KERN_ERR PREFIX
1335 "Invalid _DOD data in element %d\n", i);
1336 continue;
1337 }
1338
1339 active_list[count].value.int_val = obj->integer.value;
1340 active_list[count].bind_info = NULL;
1341 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "dod element[%d] = %d\n", i,
1342 (int)obj->integer.value));
1343 count++;
1344 }
1345
1346 kfree(video->attached_array);
1347
1348 video->attached_array = active_list;
1349 video->attached_count = count;
1350
1351out:
1352 kfree(buffer.pointer);
1353 return status;
1354}
1355
1356static int
1357acpi_video_get_next_level(struct acpi_video_device *device,
1358 u32 level_current, u32 event)
1359{
1360 int min, max, min_above, max_below, i, l, delta = 255;
1361 max = max_below = 0;
1362 min = min_above = 255;
1363 /* Find closest level to level_current */
1364 for (i = ACPI_VIDEO_FIRST_LEVEL; i < device->brightness->count; i++) {
1365 l = device->brightness->levels[i];
1366 if (abs(l - level_current) < abs(delta)) {
1367 delta = l - level_current;
1368 if (!delta)
1369 break;
1370 }
1371 }
1372 /* Ajust level_current to closest available level */
1373 level_current += delta;
1374 for (i = ACPI_VIDEO_FIRST_LEVEL; i < device->brightness->count; i++) {
1375 l = device->brightness->levels[i];
1376 if (l < min)
1377 min = l;
1378 if (l > max)
1379 max = l;
1380 if (l < min_above && l > level_current)
1381 min_above = l;
1382 if (l > max_below && l < level_current)
1383 max_below = l;
1384 }
1385
1386 switch (event) {
1387 case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:
1388 return (level_current < max) ? min_above : min;
1389 case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:
1390 return (level_current < max) ? min_above : max;
1391 case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:
1392 return (level_current > min) ? max_below : min;
1393 case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS:
1394 case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:
1395 return 0;
1396 default:
1397 return level_current;
1398 }
1399}
1400
1401static void
1402acpi_video_switch_brightness(struct work_struct *work)
1403{
1404 struct acpi_video_device *device = container_of(to_delayed_work(work),
1405 struct acpi_video_device, switch_brightness_work);
1406 unsigned long long level_current, level_next;
1407 int event = device->switch_brightness_event;
1408 int result = -EINVAL;
1409
1410 /* no warning message if acpi_backlight=vendor or a quirk is used */
1411 if (!device->backlight)
1412 return;
1413
1414 if (!device->brightness)
1415 goto out;
1416
1417 result = acpi_video_device_lcd_get_level_current(device,
1418 &level_current,
1419 false);
1420 if (result)
1421 goto out;
1422
1423 level_next = acpi_video_get_next_level(device, level_current, event);
1424
1425 result = acpi_video_device_lcd_set_level(device, level_next);
1426
1427 if (!result)
1428 backlight_force_update(device->backlight,
1429 BACKLIGHT_UPDATE_HOTKEY);
1430
1431out:
1432 if (result)
1433 printk(KERN_ERR PREFIX "Failed to switch the brightness\n");
1434}
1435
1436int acpi_video_get_edid(struct acpi_device *device, int type, int device_id,
1437 void **edid)
1438{
1439 struct acpi_video_bus *video;
1440 struct acpi_video_device *video_device;
1441 union acpi_object *buffer = NULL;
1442 acpi_status status;
1443 int i, length;
1444
1445 if (!device || !acpi_driver_data(device))
1446 return -EINVAL;
1447
1448 video = acpi_driver_data(device);
1449
1450 for (i = 0; i < video->attached_count; i++) {
1451 video_device = video->attached_array[i].bind_info;
1452 length = 256;
1453
1454 if (!video_device)
1455 continue;
1456
1457 if (!video_device->cap._DDC)
1458 continue;
1459
1460 if (type) {
1461 switch (type) {
1462 case ACPI_VIDEO_DISPLAY_CRT:
1463 if (!video_device->flags.crt)
1464 continue;
1465 break;
1466 case ACPI_VIDEO_DISPLAY_TV:
1467 if (!video_device->flags.tvout)
1468 continue;
1469 break;
1470 case ACPI_VIDEO_DISPLAY_DVI:
1471 if (!video_device->flags.dvi)
1472 continue;
1473 break;
1474 case ACPI_VIDEO_DISPLAY_LCD:
1475 if (!video_device->flags.lcd)
1476 continue;
1477 break;
1478 }
1479 } else if (video_device->device_id != device_id) {
1480 continue;
1481 }
1482
1483 status = acpi_video_device_EDID(video_device, &buffer, length);
1484
1485 if (ACPI_FAILURE(status) || !buffer ||
1486 buffer->type != ACPI_TYPE_BUFFER) {
1487 length = 128;
1488 status = acpi_video_device_EDID(video_device, &buffer,
1489 length);
1490 if (ACPI_FAILURE(status) || !buffer ||
1491 buffer->type != ACPI_TYPE_BUFFER) {
1492 continue;
1493 }
1494 }
1495
1496 *edid = buffer->buffer.pointer;
1497 return length;
1498 }
1499
1500 return -ENODEV;
1501}
1502EXPORT_SYMBOL(acpi_video_get_edid);
1503
1504static int
1505acpi_video_bus_get_devices(struct acpi_video_bus *video,
1506 struct acpi_device *device)
1507{
1508 int status = 0;
1509 struct acpi_device *dev;
1510
1511 /*
1512 * There are systems where video module known to work fine regardless
1513 * of broken _DOD and ignoring returned value here doesn't cause
1514 * any issues later.
1515 */
1516 acpi_video_device_enumerate(video);
1517
1518 list_for_each_entry(dev, &device->children, node) {
1519
1520 status = acpi_video_bus_get_one_device(dev, video);
1521 if (status) {
1522 dev_err(&dev->dev, "Can't attach device\n");
1523 break;
1524 }
1525 video->child_count++;
1526 }
1527 return status;
1528}
1529
1530/* acpi_video interface */
1531
1532/*
1533 * Win8 requires setting bit2 of _DOS to let firmware know it shouldn't
1534 * preform any automatic brightness change on receiving a notification.
1535 */
1536static int acpi_video_bus_start_devices(struct acpi_video_bus *video)
1537{
1538 return acpi_video_bus_DOS(video, 0,
1539 acpi_osi_is_win8() ? 1 : 0);
1540}
1541
1542static int acpi_video_bus_stop_devices(struct acpi_video_bus *video)
1543{
1544 return acpi_video_bus_DOS(video, 0,
1545 acpi_osi_is_win8() ? 0 : 1);
1546}
1547
1548static void acpi_video_bus_notify(struct acpi_device *device, u32 event)
1549{
1550 struct acpi_video_bus *video = acpi_driver_data(device);
1551 struct input_dev *input;
1552 int keycode = 0;
1553
1554 if (!video || !video->input)
1555 return;
1556
1557 input = video->input;
1558
1559 switch (event) {
1560 case ACPI_VIDEO_NOTIFY_SWITCH: /* User requested a switch,
1561 * most likely via hotkey. */
1562 keycode = KEY_SWITCHVIDEOMODE;
1563 break;
1564
1565 case ACPI_VIDEO_NOTIFY_PROBE: /* User plugged in or removed a video
1566 * connector. */
1567 acpi_video_device_enumerate(video);
1568 acpi_video_device_rebind(video);
1569 keycode = KEY_SWITCHVIDEOMODE;
1570 break;
1571
1572 case ACPI_VIDEO_NOTIFY_CYCLE: /* Cycle Display output hotkey pressed. */
1573 keycode = KEY_SWITCHVIDEOMODE;
1574 break;
1575 case ACPI_VIDEO_NOTIFY_NEXT_OUTPUT: /* Next Display output hotkey pressed. */
1576 keycode = KEY_VIDEO_NEXT;
1577 break;
1578 case ACPI_VIDEO_NOTIFY_PREV_OUTPUT: /* previous Display output hotkey pressed. */
1579 keycode = KEY_VIDEO_PREV;
1580 break;
1581
1582 default:
1583 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1584 "Unsupported event [0x%x]\n", event));
1585 break;
1586 }
1587
1588 if (acpi_notifier_call_chain(device, event, 0))
1589 /* Something vetoed the keypress. */
1590 keycode = 0;
1591
1592 if (keycode && (report_key_events & REPORT_OUTPUT_KEY_EVENTS)) {
1593 input_report_key(input, keycode, 1);
1594 input_sync(input);
1595 input_report_key(input, keycode, 0);
1596 input_sync(input);
1597 }
1598
1599 return;
1600}
1601
1602static void brightness_switch_event(struct acpi_video_device *video_device,
1603 u32 event)
1604{
1605 if (!brightness_switch_enabled)
1606 return;
1607
1608 video_device->switch_brightness_event = event;
1609 schedule_delayed_work(&video_device->switch_brightness_work, HZ / 10);
1610}
1611
1612static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data)
1613{
1614 struct acpi_video_device *video_device = data;
1615 struct acpi_device *device = NULL;
1616 struct acpi_video_bus *bus;
1617 struct input_dev *input;
1618 int keycode = 0;
1619
1620 if (!video_device)
1621 return;
1622
1623 device = video_device->dev;
1624 bus = video_device->video;
1625 input = bus->input;
1626
1627 switch (event) {
1628 case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS: /* Cycle brightness */
1629 brightness_switch_event(video_device, event);
1630 keycode = KEY_BRIGHTNESS_CYCLE;
1631 break;
1632 case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS: /* Increase brightness */
1633 brightness_switch_event(video_device, event);
1634 keycode = KEY_BRIGHTNESSUP;
1635 break;
1636 case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS: /* Decrease brightness */
1637 brightness_switch_event(video_device, event);
1638 keycode = KEY_BRIGHTNESSDOWN;
1639 break;
1640 case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS: /* zero brightness */
1641 brightness_switch_event(video_device, event);
1642 keycode = KEY_BRIGHTNESS_ZERO;
1643 break;
1644 case ACPI_VIDEO_NOTIFY_DISPLAY_OFF: /* display device off */
1645 brightness_switch_event(video_device, event);
1646 keycode = KEY_DISPLAY_OFF;
1647 break;
1648 default:
1649 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
1650 "Unsupported event [0x%x]\n", event));
1651 break;
1652 }
1653
1654 acpi_notifier_call_chain(device, event, 0);
1655
1656 if (keycode && (report_key_events & REPORT_BRIGHTNESS_KEY_EVENTS)) {
1657 input_report_key(input, keycode, 1);
1658 input_sync(input);
1659 input_report_key(input, keycode, 0);
1660 input_sync(input);
1661 }
1662
1663 return;
1664}
1665
1666static int acpi_video_resume(struct notifier_block *nb,
1667 unsigned long val, void *ign)
1668{
1669 struct acpi_video_bus *video;
1670 struct acpi_video_device *video_device;
1671 int i;
1672
1673 switch (val) {
1674 case PM_HIBERNATION_PREPARE:
1675 case PM_SUSPEND_PREPARE:
1676 case PM_RESTORE_PREPARE:
1677 return NOTIFY_DONE;
1678 }
1679
1680 video = container_of(nb, struct acpi_video_bus, pm_nb);
1681
1682 dev_info(&video->device->dev, "Restoring backlight state\n");
1683
1684 for (i = 0; i < video->attached_count; i++) {
1685 video_device = video->attached_array[i].bind_info;
1686 if (video_device && video_device->brightness)
1687 acpi_video_device_lcd_set_level(video_device,
1688 video_device->brightness->curr);
1689 }
1690
1691 return NOTIFY_OK;
1692}
1693
1694static acpi_status
1695acpi_video_bus_match(acpi_handle handle, u32 level, void *context,
1696 void **return_value)
1697{
1698 struct acpi_device *device = context;
1699 struct acpi_device *sibling;
1700 int result;
1701
1702 if (handle == device->handle)
1703 return AE_CTRL_TERMINATE;
1704
1705 result = acpi_bus_get_device(handle, &sibling);
1706 if (result)
1707 return AE_OK;
1708
1709 if (!strcmp(acpi_device_name(sibling), ACPI_VIDEO_BUS_NAME))
1710 return AE_ALREADY_EXISTS;
1711
1712 return AE_OK;
1713}
1714
1715static void acpi_video_dev_register_backlight(struct acpi_video_device *device)
1716{
1717 struct backlight_properties props;
1718 struct pci_dev *pdev;
1719 acpi_handle acpi_parent;
1720 struct device *parent = NULL;
1721 int result;
1722 static int count;
1723 char *name;
1724
1725 result = acpi_video_init_brightness(device);
1726 if (result)
1727 return;
1728
1729 if (disable_backlight_sysfs_if > 0)
1730 return;
1731
1732 name = kasprintf(GFP_KERNEL, "acpi_video%d", count);
1733 if (!name)
1734 return;
1735 count++;
1736
1737 acpi_get_parent(device->dev->handle, &acpi_parent);
1738
1739 pdev = acpi_get_pci_dev(acpi_parent);
1740 if (pdev) {
1741 parent = &pdev->dev;
1742 pci_dev_put(pdev);
1743 }
1744
1745 memset(&props, 0, sizeof(struct backlight_properties));
1746 props.type = BACKLIGHT_FIRMWARE;
1747 props.max_brightness =
1748 device->brightness->count - ACPI_VIDEO_FIRST_LEVEL - 1;
1749 device->backlight = backlight_device_register(name,
1750 parent,
1751 device,
1752 &acpi_backlight_ops,
1753 &props);
1754 kfree(name);
1755 if (IS_ERR(device->backlight)) {
1756 device->backlight = NULL;
1757 return;
1758 }
1759
1760 /*
1761 * Save current brightness level in case we have to restore it
1762 * before acpi_video_device_lcd_set_level() is called next time.
1763 */
1764 device->backlight->props.brightness =
1765 acpi_video_get_brightness(device->backlight);
1766
1767 device->cooling_dev = thermal_cooling_device_register("LCD",
1768 device->dev, &video_cooling_ops);
1769 if (IS_ERR(device->cooling_dev)) {
1770 /*
1771 * Set cooling_dev to NULL so we don't crash trying to free it.
1772 * Also, why the hell we are returning early and not attempt to
1773 * register video output if cooling device registration failed?
1774 * -- dtor
1775 */
1776 device->cooling_dev = NULL;
1777 return;
1778 }
1779
1780 dev_info(&device->dev->dev, "registered as cooling_device%d\n",
1781 device->cooling_dev->id);
1782 result = sysfs_create_link(&device->dev->dev.kobj,
1783 &device->cooling_dev->device.kobj,
1784 "thermal_cooling");
1785 if (result)
1786 printk(KERN_ERR PREFIX "Create sysfs link\n");
1787 result = sysfs_create_link(&device->cooling_dev->device.kobj,
1788 &device->dev->dev.kobj, "device");
1789 if (result)
1790 printk(KERN_ERR PREFIX "Create sysfs link\n");
1791}
1792
1793static void acpi_video_run_bcl_for_osi(struct acpi_video_bus *video)
1794{
1795 struct acpi_video_device *dev;
1796 union acpi_object *levels;
1797
1798 mutex_lock(&video->device_list_lock);
1799 list_for_each_entry(dev, &video->video_device_list, entry) {
1800 if (!acpi_video_device_lcd_query_levels(dev->dev->handle, &levels))
1801 kfree(levels);
1802 }
1803 mutex_unlock(&video->device_list_lock);
1804}
1805
1806static bool acpi_video_should_register_backlight(struct acpi_video_device *dev)
1807{
1808 /*
1809 * Do not create backlight device for video output
1810 * device that is not in the enumerated list.
1811 */
1812 if (!acpi_video_device_in_dod(dev)) {
1813 dev_dbg(&dev->dev->dev, "not in _DOD list, ignore\n");
1814 return false;
1815 }
1816
1817 if (only_lcd)
1818 return dev->flags.lcd;
1819 return true;
1820}
1821
1822static int acpi_video_bus_register_backlight(struct acpi_video_bus *video)
1823{
1824 struct acpi_video_device *dev;
1825
1826 if (video->backlight_registered)
1827 return 0;
1828
1829 acpi_video_run_bcl_for_osi(video);
1830
1831 if (acpi_video_get_backlight_type() != acpi_backlight_video)
1832 return 0;
1833
1834 mutex_lock(&video->device_list_lock);
1835 list_for_each_entry(dev, &video->video_device_list, entry) {
1836 if (acpi_video_should_register_backlight(dev))
1837 acpi_video_dev_register_backlight(dev);
1838 }
1839 mutex_unlock(&video->device_list_lock);
1840
1841 video->backlight_registered = true;
1842
1843 video->pm_nb.notifier_call = acpi_video_resume;
1844 video->pm_nb.priority = 0;
1845 return register_pm_notifier(&video->pm_nb);
1846}
1847
1848static void acpi_video_dev_unregister_backlight(struct acpi_video_device *device)
1849{
1850 if (device->backlight) {
1851 backlight_device_unregister(device->backlight);
1852 device->backlight = NULL;
1853 }
1854 if (device->brightness) {
1855 kfree(device->brightness->levels);
1856 kfree(device->brightness);
1857 device->brightness = NULL;
1858 }
1859 if (device->cooling_dev) {
1860 sysfs_remove_link(&device->dev->dev.kobj, "thermal_cooling");
1861 sysfs_remove_link(&device->cooling_dev->device.kobj, "device");
1862 thermal_cooling_device_unregister(device->cooling_dev);
1863 device->cooling_dev = NULL;
1864 }
1865}
1866
1867static int acpi_video_bus_unregister_backlight(struct acpi_video_bus *video)
1868{
1869 struct acpi_video_device *dev;
1870 int error;
1871
1872 if (!video->backlight_registered)
1873 return 0;
1874
1875 error = unregister_pm_notifier(&video->pm_nb);
1876
1877 mutex_lock(&video->device_list_lock);
1878 list_for_each_entry(dev, &video->video_device_list, entry)
1879 acpi_video_dev_unregister_backlight(dev);
1880 mutex_unlock(&video->device_list_lock);
1881
1882 video->backlight_registered = false;
1883
1884 return error;
1885}
1886
1887static void acpi_video_dev_add_notify_handler(struct acpi_video_device *device)
1888{
1889 acpi_status status;
1890 struct acpi_device *adev = device->dev;
1891
1892 status = acpi_install_notify_handler(adev->handle, ACPI_DEVICE_NOTIFY,
1893 acpi_video_device_notify, device);
1894 if (ACPI_FAILURE(status))
1895 dev_err(&adev->dev, "Error installing notify handler\n");
1896 else
1897 device->flags.notify = 1;
1898}
1899
1900static int acpi_video_bus_add_notify_handler(struct acpi_video_bus *video)
1901{
1902 struct input_dev *input;
1903 struct acpi_video_device *dev;
1904 int error;
1905
1906 video->input = input = input_allocate_device();
1907 if (!input) {
1908 error = -ENOMEM;
1909 goto out;
1910 }
1911
1912 error = acpi_video_bus_start_devices(video);
1913 if (error)
1914 goto err_free_input;
1915
1916 snprintf(video->phys, sizeof(video->phys),
1917 "%s/video/input0", acpi_device_hid(video->device));
1918
1919 input->name = acpi_device_name(video->device);
1920 input->phys = video->phys;
1921 input->id.bustype = BUS_HOST;
1922 input->id.product = 0x06;
1923 input->dev.parent = &video->device->dev;
1924 input->evbit[0] = BIT(EV_KEY);
1925 set_bit(KEY_SWITCHVIDEOMODE, input->keybit);
1926 set_bit(KEY_VIDEO_NEXT, input->keybit);
1927 set_bit(KEY_VIDEO_PREV, input->keybit);
1928 set_bit(KEY_BRIGHTNESS_CYCLE, input->keybit);
1929 set_bit(KEY_BRIGHTNESSUP, input->keybit);
1930 set_bit(KEY_BRIGHTNESSDOWN, input->keybit);
1931 set_bit(KEY_BRIGHTNESS_ZERO, input->keybit);
1932 set_bit(KEY_DISPLAY_OFF, input->keybit);
1933
1934 error = input_register_device(input);
1935 if (error)
1936 goto err_stop_dev;
1937
1938 mutex_lock(&video->device_list_lock);
1939 list_for_each_entry(dev, &video->video_device_list, entry)
1940 acpi_video_dev_add_notify_handler(dev);
1941 mutex_unlock(&video->device_list_lock);
1942
1943 return 0;
1944
1945err_stop_dev:
1946 acpi_video_bus_stop_devices(video);
1947err_free_input:
1948 input_free_device(input);
1949 video->input = NULL;
1950out:
1951 return error;
1952}
1953
1954static void acpi_video_dev_remove_notify_handler(struct acpi_video_device *dev)
1955{
1956 if (dev->flags.notify) {
1957 acpi_remove_notify_handler(dev->dev->handle, ACPI_DEVICE_NOTIFY,
1958 acpi_video_device_notify);
1959 dev->flags.notify = 0;
1960 }
1961}
1962
1963static void acpi_video_bus_remove_notify_handler(struct acpi_video_bus *video)
1964{
1965 struct acpi_video_device *dev;
1966
1967 mutex_lock(&video->device_list_lock);
1968 list_for_each_entry(dev, &video->video_device_list, entry)
1969 acpi_video_dev_remove_notify_handler(dev);
1970 mutex_unlock(&video->device_list_lock);
1971
1972 acpi_video_bus_stop_devices(video);
1973 input_unregister_device(video->input);
1974 video->input = NULL;
1975}
1976
1977static int acpi_video_bus_put_devices(struct acpi_video_bus *video)
1978{
1979 struct acpi_video_device *dev, *next;
1980
1981 mutex_lock(&video->device_list_lock);
1982 list_for_each_entry_safe(dev, next, &video->video_device_list, entry) {
1983 list_del(&dev->entry);
1984 kfree(dev);
1985 }
1986 mutex_unlock(&video->device_list_lock);
1987
1988 return 0;
1989}
1990
1991static int instance;
1992
1993static int acpi_video_bus_add(struct acpi_device *device)
1994{
1995 struct acpi_video_bus *video;
1996 int error;
1997 acpi_status status;
1998
1999 status = acpi_walk_namespace(ACPI_TYPE_DEVICE,
2000 device->parent->handle, 1,
2001 acpi_video_bus_match, NULL,
2002 device, NULL);
2003 if (status == AE_ALREADY_EXISTS) {
2004 printk(KERN_WARNING FW_BUG
2005 "Duplicate ACPI video bus devices for the"
2006 " same VGA controller, please try module "
2007 "parameter \"video.allow_duplicates=1\""
2008 "if the current driver doesn't work.\n");
2009 if (!allow_duplicates)
2010 return -ENODEV;
2011 }
2012
2013 video = kzalloc(sizeof(struct acpi_video_bus), GFP_KERNEL);
2014 if (!video)
2015 return -ENOMEM;
2016
2017 /* a hack to fix the duplicate name "VID" problem on T61 */
2018 if (!strcmp(device->pnp.bus_id, "VID")) {
2019 if (instance)
2020 device->pnp.bus_id[3] = '0' + instance;
2021 instance++;
2022 }
2023 /* a hack to fix the duplicate name "VGA" problem on Pa 3553 */
2024 if (!strcmp(device->pnp.bus_id, "VGA")) {
2025 if (instance)
2026 device->pnp.bus_id[3] = '0' + instance;
2027 instance++;
2028 }
2029
2030 video->device = device;
2031 strcpy(acpi_device_name(device), ACPI_VIDEO_BUS_NAME);
2032 strcpy(acpi_device_class(device), ACPI_VIDEO_CLASS);
2033 device->driver_data = video;
2034
2035 acpi_video_bus_find_cap(video);
2036 error = acpi_video_bus_check(video);
2037 if (error)
2038 goto err_free_video;
2039
2040 mutex_init(&video->device_list_lock);
2041 INIT_LIST_HEAD(&video->video_device_list);
2042
2043 error = acpi_video_bus_get_devices(video, device);
2044 if (error)
2045 goto err_put_video;
2046
2047 printk(KERN_INFO PREFIX "%s [%s] (multi-head: %s rom: %s post: %s)\n",
2048 ACPI_VIDEO_DEVICE_NAME, acpi_device_bid(device),
2049 video->flags.multihead ? "yes" : "no",
2050 video->flags.rom ? "yes" : "no",
2051 video->flags.post ? "yes" : "no");
2052 mutex_lock(&video_list_lock);
2053 list_add_tail(&video->entry, &video_bus_head);
2054 mutex_unlock(&video_list_lock);
2055
2056 acpi_video_bus_register_backlight(video);
2057 acpi_video_bus_add_notify_handler(video);
2058
2059 return 0;
2060
2061err_put_video:
2062 acpi_video_bus_put_devices(video);
2063 kfree(video->attached_array);
2064err_free_video:
2065 kfree(video);
2066 device->driver_data = NULL;
2067
2068 return error;
2069}
2070
2071static int acpi_video_bus_remove(struct acpi_device *device)
2072{
2073 struct acpi_video_bus *video = NULL;
2074
2075
2076 if (!device || !acpi_driver_data(device))
2077 return -EINVAL;
2078
2079 video = acpi_driver_data(device);
2080
2081 acpi_video_bus_remove_notify_handler(video);
2082 acpi_video_bus_unregister_backlight(video);
2083 acpi_video_bus_put_devices(video);
2084
2085 mutex_lock(&video_list_lock);
2086 list_del(&video->entry);
2087 mutex_unlock(&video_list_lock);
2088
2089 kfree(video->attached_array);
2090 kfree(video);
2091
2092 return 0;
2093}
2094
2095static int __init is_i740(struct pci_dev *dev)
2096{
2097 if (dev->device == 0x00D1)
2098 return 1;
2099 if (dev->device == 0x7000)
2100 return 1;
2101 return 0;
2102}
2103
2104static int __init intel_opregion_present(void)
2105{
2106 int opregion = 0;
2107 struct pci_dev *dev = NULL;
2108 u32 address;
2109
2110 for_each_pci_dev(dev) {
2111 if ((dev->class >> 8) != PCI_CLASS_DISPLAY_VGA)
2112 continue;
2113 if (dev->vendor != PCI_VENDOR_ID_INTEL)
2114 continue;
2115 /* We don't want to poke around undefined i740 registers */
2116 if (is_i740(dev))
2117 continue;
2118 pci_read_config_dword(dev, 0xfc, &address);
2119 if (!address)
2120 continue;
2121 opregion = 1;
2122 }
2123 return opregion;
2124}
2125
2126static bool dmi_is_desktop(void)
2127{
2128 const char *chassis_type;
2129
2130 chassis_type = dmi_get_system_info(DMI_CHASSIS_TYPE);
2131 if (!chassis_type)
2132 return false;
2133
2134 if (!strcmp(chassis_type, "3") || /* 3: Desktop */
2135 !strcmp(chassis_type, "4") || /* 4: Low Profile Desktop */
2136 !strcmp(chassis_type, "5") || /* 5: Pizza Box */
2137 !strcmp(chassis_type, "6") || /* 6: Mini Tower */
2138 !strcmp(chassis_type, "7") || /* 7: Tower */
2139 !strcmp(chassis_type, "11")) /* 11: Main Server Chassis */
2140 return true;
2141
2142 return false;
2143}
2144
2145int acpi_video_register(void)
2146{
2147 int ret = 0;
2148
2149 mutex_lock(®ister_count_mutex);
2150 if (register_count) {
2151 /*
2152 * if the function of acpi_video_register is already called,
2153 * don't register the acpi_vide_bus again and return no error.
2154 */
2155 goto leave;
2156 }
2157
2158 /*
2159 * We're seeing a lot of bogus backlight interfaces on newer machines
2160 * without a LCD such as desktops, servers and HDMI sticks. Checking
2161 * the lcd flag fixes this, so enable this on any machines which are
2162 * win8 ready (where we also prefer the native backlight driver, so
2163 * normally the acpi_video code should not register there anyways).
2164 */
2165 if (only_lcd == -1) {
2166 if (dmi_is_desktop() && acpi_osi_is_win8())
2167 only_lcd = true;
2168 else
2169 only_lcd = false;
2170 }
2171
2172 dmi_check_system(video_dmi_table);
2173
2174 ret = acpi_bus_register_driver(&acpi_video_bus);
2175 if (ret)
2176 goto leave;
2177
2178 /*
2179 * When the acpi_video_bus is loaded successfully, increase
2180 * the counter reference.
2181 */
2182 register_count = 1;
2183
2184leave:
2185 mutex_unlock(®ister_count_mutex);
2186 return ret;
2187}
2188EXPORT_SYMBOL(acpi_video_register);
2189
2190void acpi_video_unregister(void)
2191{
2192 mutex_lock(®ister_count_mutex);
2193 if (register_count) {
2194 acpi_bus_unregister_driver(&acpi_video_bus);
2195 register_count = 0;
2196 }
2197 mutex_unlock(®ister_count_mutex);
2198}
2199EXPORT_SYMBOL(acpi_video_unregister);
2200
2201void acpi_video_unregister_backlight(void)
2202{
2203 struct acpi_video_bus *video;
2204
2205 mutex_lock(®ister_count_mutex);
2206 if (register_count) {
2207 mutex_lock(&video_list_lock);
2208 list_for_each_entry(video, &video_bus_head, entry)
2209 acpi_video_bus_unregister_backlight(video);
2210 mutex_unlock(&video_list_lock);
2211 }
2212 mutex_unlock(®ister_count_mutex);
2213}
2214
2215bool acpi_video_handles_brightness_key_presses(void)
2216{
2217 bool have_video_busses;
2218
2219 mutex_lock(&video_list_lock);
2220 have_video_busses = !list_empty(&video_bus_head);
2221 mutex_unlock(&video_list_lock);
2222
2223 return have_video_busses &&
2224 (report_key_events & REPORT_BRIGHTNESS_KEY_EVENTS);
2225}
2226EXPORT_SYMBOL(acpi_video_handles_brightness_key_presses);
2227
2228/*
2229 * This is kind of nasty. Hardware using Intel chipsets may require
2230 * the video opregion code to be run first in order to initialise
2231 * state before any ACPI video calls are made. To handle this we defer
2232 * registration of the video class until the opregion code has run.
2233 */
2234
2235static int __init acpi_video_init(void)
2236{
2237 /*
2238 * Let the module load even if ACPI is disabled (e.g. due to
2239 * a broken BIOS) so that i915.ko can still be loaded on such
2240 * old systems without an AcpiOpRegion.
2241 *
2242 * acpi_video_register() will report -ENODEV later as well due
2243 * to acpi_disabled when i915.ko tries to register itself afterwards.
2244 */
2245 if (acpi_disabled)
2246 return 0;
2247
2248 if (intel_opregion_present())
2249 return 0;
2250
2251 return acpi_video_register();
2252}
2253
2254static void __exit acpi_video_exit(void)
2255{
2256 acpi_video_detect_exit();
2257 acpi_video_unregister();
2258
2259 return;
2260}
2261
2262module_init(acpi_video_init);
2263module_exit(acpi_video_exit);