projects/linux·blob master · refs

2230 lines · 57.8 KiB

1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * video.c - ACPI Video Driver
4 *
5 * Copyright (C) 2004 Luming Yu <[email protected]>
6 * Copyright (C) 2004 Bruno Ducrot <[email protected]>
7 * Copyright (C) 2006 Thomas Tuttle <[email protected]>
8 */
9
10#define pr_fmt(fmt) "ACPI: video: " fmt
11
12#include <linux/auxiliary_bus.h>
13#include <linux/kernel.h>
14#include <linux/module.h>
15#include <linux/init.h>
16#include <linux/types.h>
17#include <linux/list.h>
18#include <linux/mutex.h>
19#include <linux/input.h>
20#include <linux/backlight.h>
21#include <linux/thermal.h>
22#include <linux/sort.h>
23#include <linux/pci.h>
24#include <linux/pci_ids.h>
25#include <linux/slab.h>
26#include <linux/dmi.h>
27#include <linux/suspend.h>
28#include <linux/acpi.h>
29#include <acpi/video.h>
30#include <linux/uaccess.h>
31#include <linux/string_choices.h>
32
33#define MAX_NAME_LEN 20
34
35MODULE_AUTHOR("Bruno Ducrot");
36MODULE_DESCRIPTION("ACPI Video Driver");
37MODULE_LICENSE("GPL");
38
39static bool brightness_switch_enabled = true;
40module_param(brightness_switch_enabled, bool, 0644);
41
42/*
43 * By default, we don't allow duplicate ACPI video bus devices
44 * under the same VGA controller
45 */
46static bool allow_duplicates;
47module_param(allow_duplicates, bool, 0644);
48
49#define REPORT_OUTPUT_KEY_EVENTS 0x01
50#define REPORT_BRIGHTNESS_KEY_EVENTS 0x02
51static int report_key_events = -1;
52module_param(report_key_events, int, 0644);
53MODULE_PARM_DESC(report_key_events,
54 "0: none, 1: output changes, 2: brightness changes, 3: all");
55
56static int hw_changes_brightness = -1;
57module_param(hw_changes_brightness, int, 0644);
58MODULE_PARM_DESC(hw_changes_brightness,
59 "Set this to 1 on buggy hw which changes the brightness itself when "
60 "a hotkey is pressed: -1: auto, 0: normal 1: hw-changes-brightness");
61
62/*
63 * Whether the struct acpi_video_device_attrib::device_id_scheme bit should be
64 * assumed even if not actually set.
65 */
66static bool device_id_scheme;
67module_param(device_id_scheme, bool, 0444);
68
69static int only_lcd;
70module_param(only_lcd, int, 0444);
71
72static bool may_report_brightness_keys;
73static int register_count;
74static DEFINE_MUTEX(register_count_mutex);
75static DEFINE_MUTEX(video_list_lock);
76static LIST_HEAD(video_bus_head);
77static int acpi_video_bus_probe(struct auxiliary_device *aux_dev,
78 const struct auxiliary_device_id *id);
79static void acpi_video_bus_notify(acpi_handle handle, u32 event, void *data);
80
81/*
82 * Indices in the _BCL method response: the first two items are special,
83 * the rest are all supported levels.
84 *
85 * See page 575 of the ACPI spec 3.0
86 */
87enum acpi_video_level_idx {
88 ACPI_VIDEO_AC_LEVEL, /* level when machine has full power */
89 ACPI_VIDEO_BATTERY_LEVEL, /* level when machine is on batteries */
90 ACPI_VIDEO_FIRST_LEVEL, /* actual supported levels begin here */
91};
92
93static const struct auxiliary_device_id video_bus_auxiliary_id_table[] = {
94 { .name = "acpi.video_bus" },
95 {},
96};
97MODULE_DEVICE_TABLE(auxiliary, video_bus_auxiliary_id_table);
98
99static struct auxiliary_driver acpi_video_bus = {
100 .probe = acpi_video_bus_probe,
101 .id_table = video_bus_auxiliary_id_table,
102};
103
104struct acpi_video_bus_flags {
105 u8 multihead:1; /* can switch video heads */
106 u8 rom:1; /* can retrieve a video rom */
107 u8 post:1; /* can configure the head to */
108 u8 reserved:5;
109};
110
111struct acpi_video_bus_cap {
112 u8 _DOS:1; /* Enable/Disable output switching */
113 u8 _DOD:1; /* Enumerate all devices attached to display adapter */
114 u8 _ROM:1; /* Get ROM Data */
115 u8 _GPD:1; /* Get POST Device */
116 u8 _SPD:1; /* Set POST Device */
117 u8 _VPO:1; /* Video POST Options */
118 u8 reserved:2;
119};
120
121struct acpi_video_device_attrib {
122 u32 display_index:4; /* A zero-based instance of the Display */
123 u32 display_port_attachment:4; /* This field differentiates the display type */
124 u32 display_type:4; /* Describe the specific type in use */
125 u32 vendor_specific:4; /* Chipset Vendor Specific */
126 u32 bios_can_detect:1; /* BIOS can detect the device */
127 u32 depend_on_vga:1; /* Non-VGA output device whose power is related to
128 the VGA device. */
129 u32 pipe_id:3; /* For VGA multiple-head devices. */
130 u32 reserved:10; /* Must be 0 */
131
132 /*
133 * The device ID might not actually follow the scheme described by this
134 * struct acpi_video_device_attrib. If it does, then this bit
135 * device_id_scheme is set; otherwise, other fields should be ignored.
136 *
137 * (but also see the global flag device_id_scheme)
138 */
139 u32 device_id_scheme:1;
140};
141
142struct acpi_video_enumerated_device {
143 union {
144 u32 int_val;
145 struct acpi_video_device_attrib attrib;
146 } value;
147 struct acpi_video_device *bind_info;
148};
149
150struct acpi_video_bus {
151 struct acpi_device *device;
152 bool backlight_registered;
153 u8 dos_setting;
154 struct acpi_video_enumerated_device *attached_array;
155 u8 attached_count;
156 u8 child_count;
157 struct acpi_video_bus_cap cap;
158 struct acpi_video_bus_flags flags;
159 struct list_head video_device_list;
160 struct mutex device_list_lock; /* protects video_device_list */
161 struct list_head entry;
162 struct input_dev *input;
163 char phys[32]; /* for input device */
164 struct notifier_block pm_nb;
165};
166
167struct acpi_video_device_flags {
168 u8 crt:1;
169 u8 lcd:1;
170 u8 tvout:1;
171 u8 dvi:1;
172 u8 bios:1;
173 u8 unknown:1;
174 u8 notify:1;
175 u8 reserved:1;
176};
177
178struct acpi_video_device_cap {
179 u8 _ADR:1; /* Return the unique ID */
180 u8 _BCL:1; /* Query list of brightness control levels supported */
181 u8 _BCM:1; /* Set the brightness level */
182 u8 _BQC:1; /* Get current brightness level */
183 u8 _BCQ:1; /* Some buggy BIOS uses _BCQ instead of _BQC */
184 u8 _DDC:1; /* Return the EDID for this device */
185};
186
187struct acpi_video_device {
188 unsigned long device_id;
189 struct acpi_video_device_flags flags;
190 struct acpi_video_device_cap cap;
191 struct list_head entry;
192 struct delayed_work switch_brightness_work;
193 int switch_brightness_event;
194 struct acpi_video_bus *video;
195 struct acpi_device *dev;
196 struct acpi_video_device_brightness *brightness;
197 struct backlight_device *backlight;
198 struct thermal_cooling_device *cooling_dev;
199};
200
201static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data);
202static void acpi_video_device_rebind(struct acpi_video_bus *video);
203static void acpi_video_device_bind(struct acpi_video_bus *video,
204 struct acpi_video_device *device);
205static int acpi_video_device_enumerate(struct acpi_video_bus *video);
206static int acpi_video_device_lcd_set_level(struct acpi_video_device *device,
207 int level);
208static int acpi_video_device_lcd_get_level_current(
209 struct acpi_video_device *device,
210 unsigned long long *level, bool raw);
211static int acpi_video_get_next_level(struct acpi_video_device *device,
212 u32 level_current, u32 event);
213static void acpi_video_switch_brightness(struct work_struct *work);
214
215/* backlight device sysfs support */
216static int acpi_video_get_brightness(struct backlight_device *bd)
217{
218 unsigned long long cur_level;
219 int i;
220 struct acpi_video_device *vd = bl_get_data(bd);
221
222 if (acpi_video_device_lcd_get_level_current(vd, &cur_level, false))
223 return -EINVAL;
224 for (i = ACPI_VIDEO_FIRST_LEVEL; i < vd->brightness->count; i++) {
225 if (vd->brightness->levels[i] == cur_level)
226 return i - ACPI_VIDEO_FIRST_LEVEL;
227 }
228 return 0;
229}
230
231static int acpi_video_set_brightness(struct backlight_device *bd)
232{
233 int request_level = bd->props.brightness + ACPI_VIDEO_FIRST_LEVEL;
234 struct acpi_video_device *vd = bl_get_data(bd);
235
236 cancel_delayed_work(&vd->switch_brightness_work);
237 return acpi_video_device_lcd_set_level(vd,
238 vd->brightness->levels[request_level]);
239}
240
241static const struct backlight_ops acpi_backlight_ops = {
242 .get_brightness = acpi_video_get_brightness,
243 .update_status = acpi_video_set_brightness,
244};
245
246/* thermal cooling device callbacks */
247static int video_get_max_state(struct thermal_cooling_device *cooling_dev,
248 unsigned long *state)
249{
250 struct acpi_video_device *video = cooling_dev->devdata;
251
252 *state = video->brightness->count - ACPI_VIDEO_FIRST_LEVEL - 1;
253 return 0;
254}
255
256static int video_get_cur_state(struct thermal_cooling_device *cooling_dev,
257 unsigned long *state)
258{
259 struct acpi_video_device *video = cooling_dev->devdata;
260 unsigned long long level;
261 int offset;
262
263 if (acpi_video_device_lcd_get_level_current(video, &level, false))
264 return -EINVAL;
265 for (offset = ACPI_VIDEO_FIRST_LEVEL; offset < video->brightness->count;
266 offset++)
267 if (level == video->brightness->levels[offset]) {
268 *state = video->brightness->count - offset - 1;
269 return 0;
270 }
271
272 return -EINVAL;
273}
274
275static int
276video_set_cur_state(struct thermal_cooling_device *cooling_dev, unsigned long state)
277{
278 struct acpi_video_device *video = cooling_dev->devdata;
279 int level;
280
281 if (state >= video->brightness->count - ACPI_VIDEO_FIRST_LEVEL)
282 return -EINVAL;
283
284 state = video->brightness->count - state;
285 level = video->brightness->levels[state - 1];
286 return acpi_video_device_lcd_set_level(video, level);
287}
288
289static const struct thermal_cooling_device_ops video_cooling_ops = {
290 .get_max_state = video_get_max_state,
291 .get_cur_state = video_get_cur_state,
292 .set_cur_state = video_set_cur_state,
293};
294
295/*
296 * --------------------------------------------------------------------------
297 * Video Management
298 * --------------------------------------------------------------------------
299 */
300
301static int
302acpi_video_device_lcd_query_levels(acpi_handle handle,
303 union acpi_object **levels)
304{
305 int status;
306 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
307 union acpi_object *obj;
308
309
310 *levels = NULL;
311
312 status = acpi_evaluate_object(handle, "_BCL", NULL, &buffer);
313 if (ACPI_FAILURE(status))
314 return status;
315 obj = (union acpi_object *)buffer.pointer;
316 if (!obj || (obj->type != ACPI_TYPE_PACKAGE)) {
317 acpi_handle_info(handle, "Invalid _BCL data\n");
318 status = -EFAULT;
319 goto err;
320 }
321
322 *levels = obj;
323
324 return 0;
325
326err:
327 kfree(buffer.pointer);
328
329 return status;
330}
331
332static int
333acpi_video_device_lcd_set_level(struct acpi_video_device *device, int level)
334{
335 int status;
336 int state;
337
338 status = acpi_execute_simple_method(device->dev->handle,
339 "_BCM", level);
340 if (ACPI_FAILURE(status)) {
341 acpi_handle_info(device->dev->handle, "_BCM evaluation failed\n");
342 return -EIO;
343 }
344
345 device->brightness->curr = level;
346 for (state = ACPI_VIDEO_FIRST_LEVEL; state < device->brightness->count;
347 state++)
348 if (level == device->brightness->levels[state]) {
349 if (device->backlight)
350 device->backlight->props.brightness =
351 state - ACPI_VIDEO_FIRST_LEVEL;
352 return 0;
353 }
354
355 acpi_handle_info(device->dev->handle, "Current brightness invalid\n");
356 return -EINVAL;
357}
358
359/*
360 * For some buggy _BQC methods, we need to add a constant value to
361 * the _BQC return value to get the actual current brightness level
362 */
363
364static int bqc_offset_aml_bug_workaround;
365static int video_set_bqc_offset(const struct dmi_system_id *d)
366{
367 bqc_offset_aml_bug_workaround = 9;
368 return 0;
369}
370
371static int video_set_device_id_scheme(const struct dmi_system_id *d)
372{
373 device_id_scheme = true;
374 return 0;
375}
376
377static int video_enable_only_lcd(const struct dmi_system_id *d)
378{
379 only_lcd = true;
380 return 0;
381}
382
383static int video_set_report_key_events(const struct dmi_system_id *id)
384{
385 if (report_key_events == -1)
386 report_key_events = (uintptr_t)id->driver_data;
387 return 0;
388}
389
390static int video_hw_changes_brightness(
391 const struct dmi_system_id *d)
392{
393 if (hw_changes_brightness == -1)
394 hw_changes_brightness = 1;
395 return 0;
396}
397
398static const struct dmi_system_id video_dmi_table[] = {
399 /*
400 * Broken _BQC workaround http://bugzilla.kernel.org/show_bug.cgi?id=13121
401 */
402 {
403 .callback = video_set_bqc_offset,
404 .ident = "Acer Aspire 5720",
405 .matches = {
406 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
407 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5720"),
408 },
409 },
410 {
411 .callback = video_set_bqc_offset,
412 .ident = "Acer Aspire 5710Z",
413 .matches = {
414 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
415 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5710Z"),
416 },
417 },
418 {
419 .callback = video_set_bqc_offset,
420 .ident = "eMachines E510",
421 .matches = {
422 DMI_MATCH(DMI_BOARD_VENDOR, "EMACHINES"),
423 DMI_MATCH(DMI_PRODUCT_NAME, "eMachines E510"),
424 },
425 },
426 {
427 .callback = video_set_bqc_offset,
428 .ident = "Acer Aspire 5315",
429 .matches = {
430 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
431 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5315"),
432 },
433 },
434 {
435 .callback = video_set_bqc_offset,
436 .ident = "Acer Aspire 7720",
437 .matches = {
438 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
439 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 7720"),
440 },
441 },
442
443 /*
444 * Some machine's _DOD IDs don't have bit 31(Device ID Scheme) set
445 * but the IDs actually follow the Device ID Scheme.
446 */
447 {
448 /* https://bugzilla.kernel.org/show_bug.cgi?id=104121 */
449 .callback = video_set_device_id_scheme,
450 .ident = "ESPRIMO Mobile M9410",
451 .matches = {
452 DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU SIEMENS"),
453 DMI_MATCH(DMI_PRODUCT_NAME, "ESPRIMO Mobile M9410"),
454 },
455 },
456 /*
457 * Some machines have multiple video output devices, but only the one
458 * that is the type of LCD can do the backlight control so we should not
459 * register backlight interface for other video output devices.
460 */
461 {
462 /* https://bugzilla.kernel.org/show_bug.cgi?id=104121 */
463 .callback = video_enable_only_lcd,
464 .ident = "ESPRIMO Mobile M9410",
465 .matches = {
466 DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU SIEMENS"),
467 DMI_MATCH(DMI_PRODUCT_NAME, "ESPRIMO Mobile M9410"),
468 },
469 },
470 /*
471 * Some machines report wrong key events on the acpi-bus, suppress
472 * key event reporting on these. Note this is only intended to work
473 * around events which are plain wrong. In some cases we get double
474 * events, in this case acpi-video is considered the canonical source
475 * and the events from the other source should be filtered. E.g.
476 * by calling acpi_video_handles_brightness_key_presses() from the
477 * vendor acpi/wmi driver or by using /lib/udev/hwdb.d/60-keyboard.hwdb
478 */
479 {
480 .callback = video_set_report_key_events,
481 .driver_data = (void *)((uintptr_t)REPORT_OUTPUT_KEY_EVENTS),
482 .ident = "Dell Vostro V131",
483 .matches = {
484 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
485 DMI_MATCH(DMI_PRODUCT_NAME, "Vostro V131"),
486 },
487 },
488 {
489 .callback = video_set_report_key_events,
490 .driver_data = (void *)((uintptr_t)REPORT_BRIGHTNESS_KEY_EVENTS),
491 .ident = "Dell Vostro 3350",
492 .matches = {
493 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
494 DMI_MATCH(DMI_PRODUCT_NAME, "Vostro 3350"),
495 },
496 },
497 {
498 .callback = video_set_report_key_events,
499 .driver_data = (void *)((uintptr_t)REPORT_BRIGHTNESS_KEY_EVENTS),
500 .ident = "COLORFUL X15 AT 23",
501 .matches = {
502 DMI_MATCH(DMI_SYS_VENDOR, "COLORFUL"),
503 DMI_MATCH(DMI_PRODUCT_NAME, "X15 AT 23"),
504 },
505 },
506 /*
507 * Some machines change the brightness themselves when a brightness
508 * hotkey gets pressed, despite us telling them not to. In this case
509 * acpi_video_device_notify() should only call backlight_force_update(
510 * BACKLIGHT_UPDATE_HOTKEY) and not do anything else.
511 */
512 {
513 /* https://bugzilla.kernel.org/show_bug.cgi?id=204077 */
514 .callback = video_hw_changes_brightness,
515 .ident = "Packard Bell EasyNote MZ35",
516 .matches = {
517 DMI_MATCH(DMI_SYS_VENDOR, "Packard Bell"),
518 DMI_MATCH(DMI_PRODUCT_NAME, "EasyNote MZ35"),
519 },
520 },
521 {}
522};
523
524static unsigned long long
525acpi_video_bqc_value_to_level(struct acpi_video_device *device,
526 unsigned long long bqc_value)
527{
528 unsigned long long level;
529
530 if (device->brightness->flags._BQC_use_index) {
531 /*
532 * _BQC returns an index that doesn't account for the first 2
533 * items with special meaning (see enum acpi_video_level_idx),
534 * so we need to compensate for that by offsetting ourselves
535 */
536 if (device->brightness->flags._BCL_reversed)
537 bqc_value = device->brightness->count -
538 ACPI_VIDEO_FIRST_LEVEL - 1 - bqc_value;
539
540 level = device->brightness->levels[bqc_value +
541 ACPI_VIDEO_FIRST_LEVEL];
542 } else {
543 level = bqc_value;
544 }
545
546 level += bqc_offset_aml_bug_workaround;
547
548 return level;
549}
550
551static int
552acpi_video_device_lcd_get_level_current(struct acpi_video_device *device,
553 unsigned long long *level, bool raw)
554{
555 acpi_status status = AE_OK;
556 int i;
557
558 if (device->cap._BQC || device->cap._BCQ) {
559 char *buf = device->cap._BQC ? "_BQC" : "_BCQ";
560
561 status = acpi_evaluate_integer(device->dev->handle, buf,
562 NULL, level);
563 if (ACPI_SUCCESS(status)) {
564 if (raw) {
565 /*
566 * Caller has indicated he wants the raw
567 * value returned by _BQC, so don't furtherly
568 * mess with the value.
569 */
570 return 0;
571 }
572
573 *level = acpi_video_bqc_value_to_level(device, *level);
574
575 for (i = ACPI_VIDEO_FIRST_LEVEL;
576 i < device->brightness->count; i++)
577 if (device->brightness->levels[i] == *level) {
578 device->brightness->curr = *level;
579 return 0;
580 }
581 /*
582 * BQC returned an invalid level.
583 * Stop using it.
584 */
585 acpi_handle_info(device->dev->handle,
586 "%s returned an invalid level", buf);
587 device->cap._BQC = device->cap._BCQ = 0;
588 } else {
589 /*
590 * Fixme:
591 * should we return an error or ignore this failure?
592 * dev->brightness->curr is a cached value which stores
593 * the correct current backlight level in most cases.
594 * ACPI video backlight still works w/ buggy _BQC.
595 * http://bugzilla.kernel.org/show_bug.cgi?id=12233
596 */
597 acpi_handle_info(device->dev->handle,
598 "%s evaluation failed", buf);
599 device->cap._BQC = device->cap._BCQ = 0;
600 }
601 }
602
603 *level = device->brightness->curr;
604 return 0;
605}
606
607/**
608 * acpi_video_device_EDID() - Get EDID from ACPI _DDC
609 * @device: video output device (LCD, CRT, ..)
610 * @edid: address for returned EDID pointer
611 * @length: _DDC length to request (must be a multiple of 128)
612 *
613 * Get EDID from ACPI _DDC. On success, a pointer to the EDID data is written
614 * to the @edid address, and the length of the EDID is returned. The caller is
615 * responsible for freeing the edid pointer.
616 *
617 * Return the length of EDID (positive value) on success or error (negative
618 * value).
619 */
620static int
621acpi_video_device_EDID(struct acpi_video_device *device, void **edid, int length)
622{
623 acpi_status status;
624 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
625 union acpi_object *obj;
626 union acpi_object arg0 = { ACPI_TYPE_INTEGER };
627 struct acpi_object_list args = { 1, &arg0 };
628 int ret;
629
630 *edid = NULL;
631
632 if (!device)
633 return -ENODEV;
634 if (!length || (length % 128))
635 return -EINVAL;
636
637 arg0.integer.value = length / 128;
638
639 status = acpi_evaluate_object(device->dev->handle, "_DDC", &args, &buffer);
640 if (ACPI_FAILURE(status))
641 return -ENODEV;
642
643 obj = buffer.pointer;
644
645 /*
646 * Some buggy implementations incorrectly return the EDID buffer in an ACPI package.
647 * In this case, extract the buffer from the package.
648 */
649 if (obj && obj->type == ACPI_TYPE_PACKAGE && obj->package.count == 1)
650 obj = &obj->package.elements[0];
651
652 if (obj && obj->type == ACPI_TYPE_BUFFER) {
653 *edid = kmemdup(obj->buffer.pointer, obj->buffer.length, GFP_KERNEL);
654 ret = *edid ? obj->buffer.length : -ENOMEM;
655 } else {
656 acpi_handle_debug(device->dev->handle,
657 "Invalid _DDC data for length %d\n", length);
658 ret = -EFAULT;
659 }
660
661 kfree(buffer.pointer);
662 return ret;
663}
664
665/* bus */
666
667/*
668 * Arg:
669 * video : video bus device pointer
670 * bios_flag :
671 * 0. The system BIOS should NOT automatically switch(toggle)
672 * the active display output.
673 * 1. The system BIOS should automatically switch (toggle) the
674 * active display output. No switch event.
675 * 2. The _DGS value should be locked.
676 * 3. The system BIOS should not automatically switch (toggle) the
677 * active display output, but instead generate the display switch
678 * event notify code.
679 * lcd_flag :
680 * 0. The system BIOS should automatically control the brightness level
681 * of the LCD when:
682 * - the power changes from AC to DC (ACPI appendix B)
683 * - a brightness hotkey gets pressed (implied by Win7/8 backlight docs)
684 * 1. The system BIOS should NOT automatically control the brightness
685 * level of the LCD when:
686 * - the power changes from AC to DC (ACPI appendix B)
687 * - a brightness hotkey gets pressed (implied by Win7/8 backlight docs)
688 * Return Value:
689 * -EINVAL wrong arg.
690 */
691
692static int
693acpi_video_bus_DOS(struct acpi_video_bus *video, int bios_flag, int lcd_flag)
694{
695 acpi_status status;
696
697 if (!video->cap._DOS)
698 return 0;
699
700 if (bios_flag < 0 || bios_flag > 3 || lcd_flag < 0 || lcd_flag > 1)
701 return -EINVAL;
702 video->dos_setting = (lcd_flag << 2) | bios_flag;
703 status = acpi_execute_simple_method(video->device->handle, "_DOS",
704 (lcd_flag << 2) | bios_flag);
705 if (ACPI_FAILURE(status))
706 return -EIO;
707
708 return 0;
709}
710
711/*
712 * Simple comparison function used to sort backlight levels.
713 */
714
715static int
716acpi_video_cmp_level(const void *a, const void *b)
717{
718 return *(int *)a - *(int *)b;
719}
720
721/*
722 * Decides if _BQC/_BCQ for this system is usable
723 *
724 * We do this by changing the level first and then read out the current
725 * brightness level, if the value does not match, find out if it is using
726 * index. If not, clear the _BQC/_BCQ capability.
727 */
728static int acpi_video_bqc_quirk(struct acpi_video_device *device,
729 int max_level, int current_level)
730{
731 struct acpi_video_device_brightness *br = device->brightness;
732 int result;
733 unsigned long long level;
734 int test_level;
735
736 /* don't mess with existing known broken systems */
737 if (bqc_offset_aml_bug_workaround)
738 return 0;
739
740 /*
741 * Some systems always report current brightness level as maximum
742 * through _BQC, we need to test another value for them. However,
743 * there is a subtlety:
744 *
745 * If the _BCL package ordering is descending, the first level
746 * (br->levels[2]) is likely to be 0, and if the number of levels
747 * matches the number of steps, we might confuse a returned level to
748 * mean the index.
749 *
750 * For example:
751 *
752 * current_level = max_level = 100
753 * test_level = 0
754 * returned level = 100
755 *
756 * In this case 100 means the level, not the index, and _BCM failed.
757 * Still, if the _BCL package ordering is descending, the index of
758 * level 0 is also 100, so we assume _BQC is indexed, when it's not.
759 *
760 * This causes all _BQC calls to return bogus values causing weird
761 * behavior from the user's perspective. For example:
762 *
763 * xbacklight -set 10; xbacklight -set 20;
764 *
765 * would flash to 90% and then slowly down to the desired level (20).
766 *
767 * The solution is simple; test anything other than the first level
768 * (e.g. 1).
769 */
770 test_level = current_level == max_level
771 ? br->levels[ACPI_VIDEO_FIRST_LEVEL + 1]
772 : max_level;
773
774 result = acpi_video_device_lcd_set_level(device, test_level);
775 if (result)
776 return result;
777
778 result = acpi_video_device_lcd_get_level_current(device, &level, true);
779 if (result)
780 return result;
781
782 if (level != test_level) {
783 /* buggy _BQC found, need to find out if it uses index */
784 if (level < br->count) {
785 if (br->flags._BCL_reversed)
786 level = br->count - ACPI_VIDEO_FIRST_LEVEL - 1 - level;
787 if (br->levels[level + ACPI_VIDEO_FIRST_LEVEL] == test_level)
788 br->flags._BQC_use_index = 1;
789 }
790
791 if (!br->flags._BQC_use_index)
792 device->cap._BQC = device->cap._BCQ = 0;
793 }
794
795 return 0;
796}
797
798int acpi_video_get_levels(struct acpi_device *device,
799 struct acpi_video_device_brightness **dev_br,
800 int *pmax_level)
801{
802 union acpi_object *obj = NULL;
803 int i, max_level = 0, count = 0, level_ac_battery = 0;
804 union acpi_object *o;
805 struct acpi_video_device_brightness *br = NULL;
806 int result = 0;
807 u32 value;
808
809 if (ACPI_FAILURE(acpi_video_device_lcd_query_levels(device->handle, &obj))) {
810 acpi_handle_debug(device->handle,
811 "Could not query available LCD brightness level\n");
812 result = -ENODEV;
813 goto out;
814 }
815
816 if (obj->package.count < ACPI_VIDEO_FIRST_LEVEL) {
817 result = -EINVAL;
818 goto out;
819 }
820
821 br = kzalloc_obj(*br);
822 if (!br) {
823 result = -ENOMEM;
824 goto out;
825 }
826
827 /*
828 * Note that we have to reserve 2 extra items (ACPI_VIDEO_FIRST_LEVEL),
829 * in order to account for buggy BIOS which don't export the first two
830 * special levels (see below)
831 */
832 br->levels = kmalloc_objs(*br->levels,
833 obj->package.count + ACPI_VIDEO_FIRST_LEVEL);
834 if (!br->levels) {
835 result = -ENOMEM;
836 goto out_free;
837 }
838
839 for (i = 0; i < obj->package.count; i++) {
840 o = (union acpi_object *)&obj->package.elements[i];
841 if (o->type != ACPI_TYPE_INTEGER) {
842 acpi_handle_info(device->handle, "Invalid data\n");
843 continue;
844 }
845 value = (u32) o->integer.value;
846 /* Skip duplicate entries */
847 if (count > ACPI_VIDEO_FIRST_LEVEL
848 && br->levels[count - 1] == value)
849 continue;
850
851 br->levels[count] = value;
852
853 if (br->levels[count] > max_level)
854 max_level = br->levels[count];
855 count++;
856 }
857
858 /*
859 * some buggy BIOS don't export the levels
860 * when machine is on AC/Battery in _BCL package.
861 * In this case, the first two elements in _BCL packages
862 * are also supported brightness levels that OS should take care of.
863 */
864 for (i = ACPI_VIDEO_FIRST_LEVEL; i < count; i++) {
865 if (br->levels[i] == br->levels[ACPI_VIDEO_AC_LEVEL])
866 level_ac_battery++;
867 if (br->levels[i] == br->levels[ACPI_VIDEO_BATTERY_LEVEL])
868 level_ac_battery++;
869 }
870
871 if (level_ac_battery < ACPI_VIDEO_FIRST_LEVEL) {
872 level_ac_battery = ACPI_VIDEO_FIRST_LEVEL - level_ac_battery;
873 br->flags._BCL_no_ac_battery_levels = 1;
874 for (i = (count - 1 + level_ac_battery);
875 i >= ACPI_VIDEO_FIRST_LEVEL; i--)
876 br->levels[i] = br->levels[i - level_ac_battery];
877 count += level_ac_battery;
878 } else if (level_ac_battery > ACPI_VIDEO_FIRST_LEVEL)
879 acpi_handle_info(device->handle,
880 "Too many duplicates in _BCL package");
881
882 /* Check if the _BCL package is in a reversed order */
883 if (max_level == br->levels[ACPI_VIDEO_FIRST_LEVEL]) {
884 br->flags._BCL_reversed = 1;
885 sort(&br->levels[ACPI_VIDEO_FIRST_LEVEL],
886 count - ACPI_VIDEO_FIRST_LEVEL,
887 sizeof(br->levels[ACPI_VIDEO_FIRST_LEVEL]),
888 acpi_video_cmp_level, NULL);
889 } else if (max_level != br->levels[count - 1])
890 acpi_handle_info(device->handle,
891 "Found unordered _BCL package");
892
893 br->count = count;
894 *dev_br = br;
895 if (pmax_level)
896 *pmax_level = max_level;
897
898out:
899 kfree(obj);
900 return result;
901out_free:
902 kfree(br);
903 goto out;
904}
905EXPORT_SYMBOL(acpi_video_get_levels);
906
907/*
908 * Arg:
909 * device : video output device (LCD, CRT, ..)
910 *
911 * Return Value:
912 * Maximum brightness level
913 *
914 * Allocate and initialize device->brightness.
915 */
916
917static int
918acpi_video_init_brightness(struct acpi_video_device *device)
919{
920 int i, max_level = 0;
921 unsigned long long level, level_old;
922 struct acpi_video_device_brightness *br = NULL;
923 int result;
924
925 result = acpi_video_get_levels(device->dev, &br, &max_level);
926 if (result)
927 return result;
928 device->brightness = br;
929
930 /* _BQC uses INDEX while _BCL uses VALUE in some laptops */
931 br->curr = level = max_level;
932
933 if (!device->cap._BQC)
934 goto set_level;
935
936 result = acpi_video_device_lcd_get_level_current(device,
937 &level_old, true);
938 if (result)
939 goto out_free_levels;
940
941 result = acpi_video_bqc_quirk(device, max_level, level_old);
942 if (result)
943 goto out_free_levels;
944 /*
945 * cap._BQC may get cleared due to _BQC is found to be broken
946 * in acpi_video_bqc_quirk, so check again here.
947 */
948 if (!device->cap._BQC)
949 goto set_level;
950
951 level = acpi_video_bqc_value_to_level(device, level_old);
952 /*
953 * On some buggy laptops, _BQC returns an uninitialized
954 * value when invoked for the first time, i.e.
955 * level_old is invalid (no matter whether it's a level
956 * or an index). Set the backlight to max_level in this case.
957 */
958 for (i = ACPI_VIDEO_FIRST_LEVEL; i < br->count; i++)
959 if (level == br->levels[i])
960 break;
961 if (i == br->count || !level)
962 level = max_level;
963
964set_level:
965 result = acpi_video_device_lcd_set_level(device, level);
966 if (result)
967 goto out_free_levels;
968
969 acpi_handle_debug(device->dev->handle, "found %d brightness levels\n",
970 br->count - ACPI_VIDEO_FIRST_LEVEL);
971
972 return 0;
973
974out_free_levels:
975 kfree(br->levels);
976 kfree(br);
977 device->brightness = NULL;
978 return result;
979}
980
981/*
982 * Arg:
983 * device : video output device (LCD, CRT, ..)
984 *
985 * Return Value:
986 * None
987 *
988 * Find out all required AML methods defined under the output
989 * device.
990 */
991
992static void acpi_video_device_find_cap(struct acpi_video_device *device)
993{
994 if (acpi_has_method(device->dev->handle, "_ADR"))
995 device->cap._ADR = 1;
996 if (acpi_has_method(device->dev->handle, "_BCL"))
997 device->cap._BCL = 1;
998 if (acpi_has_method(device->dev->handle, "_BCM"))
999 device->cap._BCM = 1;
1000 if (acpi_has_method(device->dev->handle, "_BQC")) {
1001 device->cap._BQC = 1;
1002 } else if (acpi_has_method(device->dev->handle, "_BCQ")) {
1003 acpi_handle_info(device->dev->handle,
1004 "_BCQ is used instead of _BQC\n");
1005 device->cap._BCQ = 1;
1006 }
1007
1008 if (acpi_has_method(device->dev->handle, "_DDC"))
1009 device->cap._DDC = 1;
1010}
1011
1012/*
1013 * Arg:
1014 * device : video output device (VGA)
1015 *
1016 * Return Value:
1017 * None
1018 *
1019 * Find out all required AML methods defined under the video bus device.
1020 */
1021
1022static void acpi_video_bus_find_cap(struct acpi_video_bus *video)
1023{
1024 if (acpi_has_method(video->device->handle, "_DOS"))
1025 video->cap._DOS = 1;
1026 if (acpi_has_method(video->device->handle, "_DOD"))
1027 video->cap._DOD = 1;
1028 if (acpi_has_method(video->device->handle, "_ROM"))
1029 video->cap._ROM = 1;
1030 if (acpi_has_method(video->device->handle, "_GPD"))
1031 video->cap._GPD = 1;
1032 if (acpi_has_method(video->device->handle, "_SPD"))
1033 video->cap._SPD = 1;
1034 if (acpi_has_method(video->device->handle, "_VPO"))
1035 video->cap._VPO = 1;
1036}
1037
1038/*
1039 * Check whether the video bus device has required AML method to
1040 * support the desired features
1041 */
1042
1043static int acpi_video_bus_check(struct acpi_video_bus *video)
1044{
1045 acpi_status status = -ENOENT;
1046 struct pci_dev *dev;
1047
1048 if (!video)
1049 return -EINVAL;
1050
1051 dev = acpi_dev_get_pci_dev(video->device);
1052 if (!dev)
1053 return -ENODEV;
1054 pci_dev_put(dev);
1055
1056 /*
1057 * Since there is no HID, CID and so on for VGA driver, we have
1058 * to check well known required nodes.
1059 */
1060
1061 /* Does this device support video switching? */
1062 if (video->cap._DOS || video->cap._DOD) {
1063 if (!video->cap._DOS) {
1064 pr_info(FW_BUG "ACPI(%s) defines _DOD but not _DOS\n",
1065 acpi_device_bid(video->device));
1066 }
1067 video->flags.multihead = 1;
1068 status = 0;
1069 }
1070
1071 /* Does this device support retrieving a video ROM? */
1072 if (video->cap._ROM) {
1073 video->flags.rom = 1;
1074 status = 0;
1075 }
1076
1077 /* Does this device support configuring which video device to POST? */
1078 if (video->cap._GPD && video->cap._SPD && video->cap._VPO) {
1079 video->flags.post = 1;
1080 status = 0;
1081 }
1082
1083 return status;
1084}
1085
1086/*
1087 * --------------------------------------------------------------------------
1088 * Driver Interface
1089 * --------------------------------------------------------------------------
1090 */
1091
1092/* device interface */
1093static struct acpi_video_device_attrib *
1094acpi_video_get_device_attr(struct acpi_video_bus *video, unsigned long device_id)
1095{
1096 struct acpi_video_enumerated_device *ids;
1097 int i;
1098
1099 for (i = 0; i < video->attached_count; i++) {
1100 ids = &video->attached_array[i];
1101 if ((ids->value.int_val & 0xffff) == device_id)
1102 return &ids->value.attrib;
1103 }
1104
1105 return NULL;
1106}
1107
1108static int
1109acpi_video_get_device_type(struct acpi_video_bus *video,
1110 unsigned long device_id)
1111{
1112 struct acpi_video_enumerated_device *ids;
1113 int i;
1114
1115 for (i = 0; i < video->attached_count; i++) {
1116 ids = &video->attached_array[i];
1117 if ((ids->value.int_val & 0xffff) == device_id)
1118 return ids->value.int_val;
1119 }
1120
1121 return 0;
1122}
1123
1124static int acpi_video_bus_get_one_device(struct acpi_device *device, void *arg)
1125{
1126 struct acpi_video_bus *video = arg;
1127 struct acpi_video_device_attrib *attribute;
1128 struct acpi_video_device *data;
1129 int device_type;
1130 u64 device_id;
1131
1132 /* Skip devices without _ADR instead of failing. */
1133 if (acpi_get_local_u64_address(device->handle, &device_id))
1134 goto exit;
1135
1136 data = kzalloc_obj(struct acpi_video_device);
1137 if (!data) {
1138 dev_dbg(&device->dev, "Cannot attach\n");
1139 return -ENOMEM;
1140 }
1141
1142 data->device_id = device_id;
1143 data->video = video;
1144 data->dev = device;
1145 INIT_DELAYED_WORK(&data->switch_brightness_work,
1146 acpi_video_switch_brightness);
1147
1148 attribute = acpi_video_get_device_attr(video, device_id);
1149
1150 if (attribute && (attribute->device_id_scheme || device_id_scheme)) {
1151 switch (attribute->display_type) {
1152 case ACPI_VIDEO_DISPLAY_CRT:
1153 data->flags.crt = 1;
1154 break;
1155 case ACPI_VIDEO_DISPLAY_TV:
1156 data->flags.tvout = 1;
1157 break;
1158 case ACPI_VIDEO_DISPLAY_DVI:
1159 data->flags.dvi = 1;
1160 break;
1161 case ACPI_VIDEO_DISPLAY_LCD:
1162 data->flags.lcd = 1;
1163 break;
1164 default:
1165 data->flags.unknown = 1;
1166 break;
1167 }
1168 if (attribute->bios_can_detect)
1169 data->flags.bios = 1;
1170 } else {
1171 /* Check for legacy IDs */
1172 device_type = acpi_video_get_device_type(video, device_id);
1173 /* Ignore bits 16 and 18-20 */
1174 switch (device_type & 0xffe2ffff) {
1175 case ACPI_VIDEO_DISPLAY_LEGACY_MONITOR:
1176 data->flags.crt = 1;
1177 break;
1178 case ACPI_VIDEO_DISPLAY_LEGACY_PANEL:
1179 data->flags.lcd = 1;
1180 break;
1181 case ACPI_VIDEO_DISPLAY_LEGACY_TV:
1182 data->flags.tvout = 1;
1183 break;
1184 default:
1185 data->flags.unknown = 1;
1186 }
1187 }
1188
1189 acpi_video_device_bind(video, data);
1190 acpi_video_device_find_cap(data);
1191
1192 if (data->cap._BCM && data->cap._BCL)
1193 may_report_brightness_keys = true;
1194
1195 mutex_lock(&video->device_list_lock);
1196 list_add_tail(&data->entry, &video->video_device_list);
1197 mutex_unlock(&video->device_list_lock);
1198
1199exit:
1200 video->child_count++;
1201 return 0;
1202}
1203
1204/*
1205 * Arg:
1206 * video : video bus device
1207 *
1208 * Return:
1209 * none
1210 *
1211 * Enumerate the video device list of the video bus,
1212 * bind the ids with the corresponding video devices
1213 * under the video bus.
1214 */
1215
1216static void acpi_video_device_rebind(struct acpi_video_bus *video)
1217{
1218 struct acpi_video_device *dev;
1219
1220 mutex_lock(&video->device_list_lock);
1221
1222 list_for_each_entry(dev, &video->video_device_list, entry)
1223 acpi_video_device_bind(video, dev);
1224
1225 mutex_unlock(&video->device_list_lock);
1226}
1227
1228/*
1229 * Arg:
1230 * video : video bus device
1231 * device : video output device under the video
1232 * bus
1233 *
1234 * Return:
1235 * none
1236 *
1237 * Bind the ids with the corresponding video devices
1238 * under the video bus.
1239 */
1240
1241static void
1242acpi_video_device_bind(struct acpi_video_bus *video,
1243 struct acpi_video_device *device)
1244{
1245 struct acpi_video_enumerated_device *ids;
1246 int i;
1247
1248 for (i = 0; i < video->attached_count; i++) {
1249 ids = &video->attached_array[i];
1250 if (device->device_id == (ids->value.int_val & 0xffff)) {
1251 ids->bind_info = device;
1252 acpi_handle_debug(video->device->handle, "%s: %d\n",
1253 __func__, i);
1254 }
1255 }
1256}
1257
1258static bool acpi_video_device_in_dod(struct acpi_video_device *device)
1259{
1260 struct acpi_video_bus *video = device->video;
1261 int i;
1262
1263 /*
1264 * If we have a broken _DOD or we have more than 8 output devices
1265 * under the graphics controller node that we can't proper deal with
1266 * in the operation region code currently, no need to test.
1267 */
1268 if (!video->attached_count || video->child_count > 8)
1269 return true;
1270
1271 for (i = 0; i < video->attached_count; i++) {
1272 if ((video->attached_array[i].value.int_val & 0xfff) ==
1273 (device->device_id & 0xfff))
1274 return true;
1275 }
1276
1277 return false;
1278}
1279
1280/*
1281 * Arg:
1282 * video : video bus device
1283 *
1284 * Return:
1285 * < 0 : error
1286 *
1287 * Call _DOD to enumerate all devices attached to display adapter
1288 *
1289 */
1290
1291static int acpi_video_device_enumerate(struct acpi_video_bus *video)
1292{
1293 int status;
1294 int count;
1295 int i;
1296 struct acpi_video_enumerated_device *active_list;
1297 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
1298 union acpi_object *dod = NULL;
1299 union acpi_object *obj;
1300
1301 if (!video->cap._DOD)
1302 return AE_NOT_EXIST;
1303
1304 status = acpi_evaluate_object(video->device->handle, "_DOD", NULL, &buffer);
1305 if (ACPI_FAILURE(status)) {
1306 acpi_handle_info(video->device->handle,
1307 "_DOD evaluation failed: %s\n",
1308 acpi_format_exception(status));
1309 return status;
1310 }
1311
1312 dod = buffer.pointer;
1313 if (!dod || (dod->type != ACPI_TYPE_PACKAGE)) {
1314 acpi_handle_info(video->device->handle, "Invalid _DOD data\n");
1315 status = -EFAULT;
1316 goto out;
1317 }
1318
1319 acpi_handle_debug(video->device->handle, "Found %d video heads in _DOD\n",
1320 dod->package.count);
1321
1322 active_list = kzalloc_objs(struct acpi_video_enumerated_device,
1323 1 + dod->package.count);
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 acpi_handle_info(video->device->handle,
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
1342 acpi_handle_debug(video->device->handle,
1343 "_DOD element[%d] = %d\n", i,
1344 (int)obj->integer.value);
1345
1346 count++;
1347 }
1348
1349 kfree(video->attached_array);
1350
1351 video->attached_array = active_list;
1352 video->attached_count = count;
1353
1354out:
1355 kfree(buffer.pointer);
1356 return status;
1357}
1358
1359static int
1360acpi_video_get_next_level(struct acpi_video_device *device,
1361 u32 level_current, u32 event)
1362{
1363 int min, max, min_above, max_below, i, l, delta = 255;
1364 max = max_below = 0;
1365 min = min_above = 255;
1366 /* Find closest level to level_current */
1367 for (i = ACPI_VIDEO_FIRST_LEVEL; i < device->brightness->count; i++) {
1368 l = device->brightness->levels[i];
1369 if (abs(l - level_current) < abs(delta)) {
1370 delta = l - level_current;
1371 if (!delta)
1372 break;
1373 }
1374 }
1375 /* Adjust level_current to closest available level */
1376 level_current += delta;
1377 for (i = ACPI_VIDEO_FIRST_LEVEL; i < device->brightness->count; i++) {
1378 l = device->brightness->levels[i];
1379 if (l < min)
1380 min = l;
1381 if (l > max)
1382 max = l;
1383 if (l < min_above && l > level_current)
1384 min_above = l;
1385 if (l > max_below && l < level_current)
1386 max_below = l;
1387 }
1388
1389 switch (event) {
1390 case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS:
1391 return (level_current < max) ? min_above : min;
1392 case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS:
1393 return (level_current < max) ? min_above : max;
1394 case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS:
1395 return (level_current > min) ? max_below : min;
1396 case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS:
1397 case ACPI_VIDEO_NOTIFY_DISPLAY_OFF:
1398 return 0;
1399 default:
1400 return level_current;
1401 }
1402}
1403
1404static void
1405acpi_video_switch_brightness(struct work_struct *work)
1406{
1407 struct acpi_video_device *device = container_of(to_delayed_work(work),
1408 struct acpi_video_device, switch_brightness_work);
1409 unsigned long long level_current, level_next;
1410 int event = device->switch_brightness_event;
1411 int result = -EINVAL;
1412
1413 /* no warning message if acpi_backlight=vendor or a quirk is used */
1414 if (!device->backlight)
1415 return;
1416
1417 if (!device->brightness)
1418 goto out;
1419
1420 result = acpi_video_device_lcd_get_level_current(device,
1421 &level_current,
1422 false);
1423 if (result)
1424 goto out;
1425
1426 level_next = acpi_video_get_next_level(device, level_current, event);
1427
1428 result = acpi_video_device_lcd_set_level(device, level_next);
1429
1430 if (!result)
1431 backlight_force_update(device->backlight,
1432 BACKLIGHT_UPDATE_HOTKEY);
1433
1434out:
1435 if (result)
1436 acpi_handle_info(device->dev->handle,
1437 "Failed to switch brightness\n");
1438}
1439
1440int acpi_video_get_edid(struct acpi_device *device, int type, int device_id,
1441 void **edid)
1442{
1443 struct acpi_video_bus *video;
1444 struct acpi_video_device *video_device;
1445 int i, length, ret;
1446
1447 if (!device || !acpi_driver_data(device))
1448 return -EINVAL;
1449
1450 video = acpi_driver_data(device);
1451
1452 for (i = 0; i < video->attached_count; i++) {
1453 video_device = video->attached_array[i].bind_info;
1454
1455 if (!video_device)
1456 continue;
1457
1458 if (!video_device->cap._DDC)
1459 continue;
1460
1461 if (type) {
1462 switch (type) {
1463 case ACPI_VIDEO_DISPLAY_CRT:
1464 if (!video_device->flags.crt)
1465 continue;
1466 break;
1467 case ACPI_VIDEO_DISPLAY_TV:
1468 if (!video_device->flags.tvout)
1469 continue;
1470 break;
1471 case ACPI_VIDEO_DISPLAY_DVI:
1472 if (!video_device->flags.dvi)
1473 continue;
1474 break;
1475 case ACPI_VIDEO_DISPLAY_LCD:
1476 if (!video_device->flags.lcd)
1477 continue;
1478 break;
1479 }
1480 } else if (video_device->device_id != device_id) {
1481 continue;
1482 }
1483
1484 for (length = 512; length > 0; length -= 128) {
1485 ret = acpi_video_device_EDID(video_device, edid, length);
1486 if (ret > 0)
1487 return ret;
1488 }
1489 }
1490
1491 return -ENODEV;
1492}
1493EXPORT_SYMBOL(acpi_video_get_edid);
1494
1495static void acpi_video_bus_put_devices(void *data)
1496{
1497 struct acpi_video_bus *video = data;
1498 struct acpi_video_device *dev, *next;
1499
1500 mutex_lock(&video->device_list_lock);
1501 list_for_each_entry_safe(dev, next, &video->video_device_list, entry) {
1502 list_del(&dev->entry);
1503 kfree(dev);
1504 }
1505 mutex_unlock(&video->device_list_lock);
1506
1507 kfree(video->attached_array);
1508 video->attached_array = NULL;
1509}
1510
1511static int devm_acpi_video_bus_get_devices(struct device *dev,
1512 struct acpi_video_bus *video)
1513{
1514 int ret;
1515
1516 ret = devm_add_action(dev, acpi_video_bus_put_devices, video);
1517 if (ret)
1518 return ret;
1519
1520 /*
1521 * There are systems where video module known to work fine regardless
1522 * of broken _DOD and ignoring returned value here doesn't cause
1523 * any issues later.
1524 */
1525 acpi_video_device_enumerate(video);
1526
1527 return acpi_dev_for_each_child(video->device,
1528 acpi_video_bus_get_one_device, video);
1529}
1530
1531/* acpi_video interface */
1532
1533/*
1534 * Win8 requires setting bit2 of _DOS to let firmware know it shouldn't
1535 * perform any automatic brightness change on receiving a notification.
1536 */
1537static int acpi_video_bus_start_devices(struct acpi_video_bus *video)
1538{
1539 return acpi_video_bus_DOS(video, 0,
1540 acpi_osi_is_win8() ? 1 : 0);
1541}
1542
1543static int acpi_video_bus_stop_devices(struct acpi_video_bus *video)
1544{
1545 return acpi_video_bus_DOS(video, 0,
1546 acpi_osi_is_win8() ? 0 : 1);
1547}
1548
1549static void acpi_video_bus_notify(acpi_handle handle, u32 event, void *data)
1550{
1551 struct acpi_video_bus *video = data;
1552 struct acpi_device *device = video->device;
1553 struct input_dev *input;
1554 int keycode = 0;
1555
1556 input = video->input;
1557
1558 switch (event) {
1559 case ACPI_VIDEO_NOTIFY_SWITCH: /* User requested a switch,
1560 * most likely via hotkey. */
1561 keycode = KEY_SWITCHVIDEOMODE;
1562 break;
1563
1564 case ACPI_VIDEO_NOTIFY_PROBE: /* User plugged in or removed a video
1565 * connector. */
1566 acpi_video_device_enumerate(video);
1567 acpi_video_device_rebind(video);
1568 keycode = KEY_SWITCHVIDEOMODE;
1569 break;
1570
1571 case ACPI_VIDEO_NOTIFY_CYCLE: /* Cycle Display output hotkey pressed. */
1572 keycode = KEY_SWITCHVIDEOMODE;
1573 break;
1574 case ACPI_VIDEO_NOTIFY_NEXT_OUTPUT: /* Next Display output hotkey pressed. */
1575 keycode = KEY_VIDEO_NEXT;
1576 break;
1577 case ACPI_VIDEO_NOTIFY_PREV_OUTPUT: /* previous Display output hotkey pressed. */
1578 keycode = KEY_VIDEO_PREV;
1579 break;
1580
1581 default:
1582 acpi_handle_debug(device->handle, "Unsupported event [0x%x]\n",
1583 event);
1584 break;
1585 }
1586
1587 if (acpi_notifier_call_chain(ACPI_VIDEO_CLASS, acpi_device_bid(device),
1588 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
1600static void brightness_switch_event(struct acpi_video_device *video_device,
1601 u32 event)
1602{
1603 if (!brightness_switch_enabled)
1604 return;
1605
1606 video_device->switch_brightness_event = event;
1607 schedule_delayed_work(&video_device->switch_brightness_work, HZ / 10);
1608}
1609
1610static void acpi_video_device_notify(acpi_handle handle, u32 event, void *data)
1611{
1612 struct acpi_video_device *video_device = data;
1613 struct acpi_device *device = NULL;
1614 struct acpi_video_bus *bus;
1615 struct input_dev *input;
1616 int keycode = 0;
1617
1618 if (!video_device)
1619 return;
1620
1621 device = video_device->dev;
1622 bus = video_device->video;
1623 input = bus->input;
1624
1625 if (hw_changes_brightness > 0) {
1626 if (video_device->backlight)
1627 backlight_force_update(video_device->backlight,
1628 BACKLIGHT_UPDATE_HOTKEY);
1629 acpi_notifier_call_chain(ACPI_VIDEO_CLASS, acpi_device_bid(device),
1630 event, 0);
1631 return;
1632 }
1633
1634 switch (event) {
1635 case ACPI_VIDEO_NOTIFY_CYCLE_BRIGHTNESS: /* Cycle brightness */
1636 brightness_switch_event(video_device, event);
1637 keycode = KEY_BRIGHTNESS_CYCLE;
1638 break;
1639 case ACPI_VIDEO_NOTIFY_INC_BRIGHTNESS: /* Increase brightness */
1640 brightness_switch_event(video_device, event);
1641 keycode = KEY_BRIGHTNESSUP;
1642 break;
1643 case ACPI_VIDEO_NOTIFY_DEC_BRIGHTNESS: /* Decrease brightness */
1644 brightness_switch_event(video_device, event);
1645 keycode = KEY_BRIGHTNESSDOWN;
1646 break;
1647 case ACPI_VIDEO_NOTIFY_ZERO_BRIGHTNESS: /* zero brightness */
1648 brightness_switch_event(video_device, event);
1649 keycode = KEY_BRIGHTNESS_ZERO;
1650 break;
1651 case ACPI_VIDEO_NOTIFY_DISPLAY_OFF: /* display device off */
1652 brightness_switch_event(video_device, event);
1653 keycode = KEY_DISPLAY_OFF;
1654 break;
1655 default:
1656 acpi_handle_debug(handle, "Unsupported event [0x%x]\n", event);
1657 break;
1658 }
1659
1660 if (keycode)
1661 may_report_brightness_keys = true;
1662
1663 acpi_notifier_call_chain(ACPI_VIDEO_CLASS, acpi_device_bid(device),
1664 event, 0);
1665
1666 if (keycode && (report_key_events & REPORT_BRIGHTNESS_KEY_EVENTS)) {
1667 input_report_key(input, keycode, 1);
1668 input_sync(input);
1669 input_report_key(input, keycode, 0);
1670 input_sync(input);
1671 }
1672}
1673
1674static int acpi_video_resume(struct notifier_block *nb,
1675 unsigned long val, void *ign)
1676{
1677 struct acpi_video_bus *video;
1678 struct acpi_video_device *video_device;
1679 int i;
1680
1681 switch (val) {
1682 case PM_POST_HIBERNATION:
1683 case PM_POST_SUSPEND:
1684 case PM_POST_RESTORE:
1685 video = container_of(nb, struct acpi_video_bus, pm_nb);
1686
1687 dev_info(&video->device->dev, "Restoring backlight state\n");
1688
1689 for (i = 0; i < video->attached_count; i++) {
1690 video_device = video->attached_array[i].bind_info;
1691 if (video_device && video_device->brightness)
1692 acpi_video_device_lcd_set_level(video_device,
1693 video_device->brightness->curr);
1694 }
1695
1696 return NOTIFY_OK;
1697 }
1698 return NOTIFY_DONE;
1699}
1700
1701static void acpi_video_dev_register_backlight(struct acpi_video_device *device)
1702{
1703 struct backlight_properties props;
1704 struct pci_dev *pdev;
1705 struct device *parent = NULL;
1706 int result;
1707 static int count;
1708 char *name;
1709
1710 result = acpi_video_init_brightness(device);
1711 if (result)
1712 return;
1713
1714 name = kasprintf(GFP_KERNEL, "acpi_video%d", count);
1715 if (!name)
1716 return;
1717 count++;
1718
1719 pdev = acpi_dev_get_pci_dev(acpi_dev_parent(device->dev));
1720 if (pdev)
1721 parent = &pdev->dev;
1722
1723 memset(&props, 0, sizeof(struct backlight_properties));
1724 props.type = BACKLIGHT_FIRMWARE;
1725 props.max_brightness =
1726 device->brightness->count - ACPI_VIDEO_FIRST_LEVEL - 1;
1727 device->backlight = backlight_device_register(name,
1728 parent,
1729 device,
1730 &acpi_backlight_ops,
1731 &props);
1732 put_device(parent);
1733 kfree(name);
1734 if (IS_ERR(device->backlight)) {
1735 device->backlight = NULL;
1736 return;
1737 }
1738
1739 /*
1740 * Save current brightness level in case we have to restore it
1741 * before acpi_video_device_lcd_set_level() is called next time.
1742 */
1743 device->backlight->props.brightness =
1744 acpi_video_get_brightness(device->backlight);
1745
1746 device->cooling_dev = thermal_cooling_device_register("LCD", device,
1747 &video_cooling_ops);
1748 if (IS_ERR(device->cooling_dev)) {
1749 /*
1750 * Set cooling_dev to NULL so we don't crash trying to free it.
1751 * Also, why the hell we are returning early and not attempt to
1752 * register video output if cooling device registration failed?
1753 * -- dtor
1754 */
1755 device->cooling_dev = NULL;
1756 return;
1757 }
1758
1759 dev_info(&device->dev->dev, "registered as cooling_device%d\n",
1760 device->cooling_dev->id);
1761 result = sysfs_create_link(&device->dev->dev.kobj,
1762 &device->cooling_dev->device.kobj,
1763 "thermal_cooling");
1764 if (result)
1765 pr_info("sysfs link creation failed\n");
1766
1767 result = sysfs_create_link(&device->cooling_dev->device.kobj,
1768 &device->dev->dev.kobj, "device");
1769 if (result)
1770 pr_info("Reverse sysfs link creation failed\n");
1771}
1772
1773static void acpi_video_run_bcl_for_osi(struct acpi_video_bus *video)
1774{
1775 struct acpi_video_device *dev;
1776 union acpi_object *levels;
1777
1778 mutex_lock(&video->device_list_lock);
1779 list_for_each_entry(dev, &video->video_device_list, entry) {
1780 if (!acpi_video_device_lcd_query_levels(dev->dev->handle, &levels))
1781 kfree(levels);
1782 }
1783 mutex_unlock(&video->device_list_lock);
1784}
1785
1786static bool acpi_video_should_register_backlight(struct acpi_video_device *dev)
1787{
1788 /*
1789 * Do not create backlight device for video output
1790 * device that is not in the enumerated list.
1791 */
1792 if (!acpi_video_device_in_dod(dev)) {
1793 dev_dbg(&dev->dev->dev, "not in _DOD list, ignore\n");
1794 return false;
1795 }
1796
1797 if (only_lcd)
1798 return dev->flags.lcd;
1799 return true;
1800}
1801
1802static int acpi_video_bus_register_backlight(struct acpi_video_bus *video)
1803{
1804 struct acpi_video_device *dev;
1805
1806 if (video->backlight_registered)
1807 return 0;
1808
1809 if (acpi_video_get_backlight_type() != acpi_backlight_video)
1810 return 0;
1811
1812 mutex_lock(&video->device_list_lock);
1813 list_for_each_entry(dev, &video->video_device_list, entry) {
1814 if (acpi_video_should_register_backlight(dev))
1815 acpi_video_dev_register_backlight(dev);
1816 }
1817 mutex_unlock(&video->device_list_lock);
1818
1819 video->backlight_registered = true;
1820
1821 video->pm_nb.notifier_call = acpi_video_resume;
1822 video->pm_nb.priority = 0;
1823 return register_pm_notifier(&video->pm_nb);
1824}
1825
1826static void acpi_video_dev_unregister_backlight(struct acpi_video_device *device)
1827{
1828 if (device->backlight) {
1829 backlight_device_unregister(device->backlight);
1830 device->backlight = NULL;
1831 }
1832 if (device->brightness) {
1833 kfree(device->brightness->levels);
1834 kfree(device->brightness);
1835 device->brightness = NULL;
1836 }
1837 if (device->cooling_dev) {
1838 sysfs_remove_link(&device->dev->dev.kobj, "thermal_cooling");
1839 sysfs_remove_link(&device->cooling_dev->device.kobj, "device");
1840 thermal_cooling_device_unregister(device->cooling_dev);
1841 device->cooling_dev = NULL;
1842 }
1843}
1844
1845static int acpi_video_bus_unregister_backlight(struct acpi_video_bus *video)
1846{
1847 struct acpi_video_device *dev;
1848 int error;
1849
1850 if (!video->backlight_registered)
1851 return 0;
1852
1853 error = unregister_pm_notifier(&video->pm_nb);
1854
1855 mutex_lock(&video->device_list_lock);
1856 list_for_each_entry(dev, &video->video_device_list, entry)
1857 acpi_video_dev_unregister_backlight(dev);
1858 mutex_unlock(&video->device_list_lock);
1859
1860 video->backlight_registered = false;
1861
1862 return error;
1863}
1864
1865static void acpi_video_dev_add_notify_handler(struct acpi_video_device *device)
1866{
1867 acpi_status status;
1868 struct acpi_device *adev = device->dev;
1869
1870 status = acpi_install_notify_handler(adev->handle, ACPI_DEVICE_NOTIFY,
1871 acpi_video_device_notify, device);
1872 if (ACPI_FAILURE(status))
1873 dev_err(&adev->dev, "Error installing notify handler\n");
1874 else
1875 device->flags.notify = 1;
1876}
1877
1878static int acpi_video_bus_add_notify_handler(struct acpi_video_bus *video,
1879 struct device *parent)
1880{
1881 struct input_dev *input;
1882 struct acpi_video_device *dev;
1883 int error;
1884
1885 video->input = input = input_allocate_device();
1886 if (!input) {
1887 error = -ENOMEM;
1888 goto out;
1889 }
1890
1891 error = acpi_video_bus_start_devices(video);
1892 if (error)
1893 goto err_free_input;
1894
1895 snprintf(video->phys, sizeof(video->phys),
1896 "%s/video/input0", acpi_device_hid(video->device));
1897
1898 input->name = "Video Bus";
1899 input->phys = video->phys;
1900 input->id.bustype = BUS_HOST;
1901 input->id.product = 0x06;
1902 input->dev.parent = parent;
1903 input->evbit[0] = BIT(EV_KEY);
1904 set_bit(KEY_SWITCHVIDEOMODE, input->keybit);
1905 set_bit(KEY_VIDEO_NEXT, input->keybit);
1906 set_bit(KEY_VIDEO_PREV, input->keybit);
1907 set_bit(KEY_BRIGHTNESS_CYCLE, input->keybit);
1908 set_bit(KEY_BRIGHTNESSUP, input->keybit);
1909 set_bit(KEY_BRIGHTNESSDOWN, input->keybit);
1910 set_bit(KEY_BRIGHTNESS_ZERO, input->keybit);
1911 set_bit(KEY_DISPLAY_OFF, input->keybit);
1912
1913 error = input_register_device(input);
1914 if (error)
1915 goto err_stop_dev;
1916
1917 mutex_lock(&video->device_list_lock);
1918 list_for_each_entry(dev, &video->video_device_list, entry)
1919 acpi_video_dev_add_notify_handler(dev);
1920 mutex_unlock(&video->device_list_lock);
1921
1922 return 0;
1923
1924err_stop_dev:
1925 acpi_video_bus_stop_devices(video);
1926err_free_input:
1927 input_free_device(input);
1928 video->input = NULL;
1929out:
1930 return error;
1931}
1932
1933static void acpi_video_dev_remove_notify_handler(struct acpi_video_device *dev)
1934{
1935 if (dev->flags.notify) {
1936 acpi_remove_notify_handler(dev->dev->handle, ACPI_DEVICE_NOTIFY,
1937 acpi_video_device_notify);
1938 dev->flags.notify = 0;
1939 }
1940}
1941
1942static void acpi_video_bus_remove_notify_handler(void *data)
1943{
1944 struct acpi_video_bus *video = data;
1945 struct acpi_video_device *dev;
1946
1947 mutex_lock(&video->device_list_lock);
1948 list_for_each_entry(dev, &video->video_device_list, entry) {
1949 acpi_video_dev_remove_notify_handler(dev);
1950 cancel_delayed_work_sync(&dev->switch_brightness_work);
1951 }
1952 mutex_unlock(&video->device_list_lock);
1953
1954 acpi_video_bus_stop_devices(video);
1955 input_unregister_device(video->input);
1956 video->input = NULL;
1957}
1958
1959static void acpi_video_bus_free(void *data)
1960{
1961 struct acpi_video_bus *video = data;
1962
1963 video->device->driver_data = NULL;
1964 kfree(video);
1965}
1966
1967static void acpi_video_bus_del(void *data)
1968{
1969 struct acpi_video_bus *video = data;
1970
1971 mutex_lock(&video_list_lock);
1972 list_del(&video->entry);
1973 mutex_unlock(&video_list_lock);
1974
1975 acpi_video_bus_unregister_backlight(video);
1976}
1977
1978static int duplicate_dev_check(struct device *sibling, void *data)
1979{
1980 struct acpi_video_bus *video;
1981
1982 if (sibling == data || !dev_is_auxiliary(sibling))
1983 return 0;
1984
1985 guard(mutex)(&video_list_lock);
1986
1987 list_for_each_entry(video, &video_bus_head, entry) {
1988 if (video == dev_get_drvdata(sibling))
1989 return -EEXIST;
1990 }
1991
1992 return 0;
1993}
1994
1995static bool acpi_video_bus_dev_is_duplicate(struct device *dev)
1996{
1997 return device_for_each_child(dev->parent, dev, duplicate_dev_check);
1998}
1999
2000static int acpi_video_bus_probe(struct auxiliary_device *aux_dev,
2001 const struct auxiliary_device_id *id_unused)
2002{
2003 struct device *dev = &aux_dev->dev;
2004 struct acpi_device *device = ACPI_COMPANION(dev);
2005 static DEFINE_MUTEX(probe_lock);
2006 struct acpi_video_bus *video;
2007 static int instance;
2008 bool auto_detect;
2009 int error;
2010
2011 /* Probe one video bus device at a time in case there are duplicates. */
2012 guard(mutex)(&probe_lock);
2013
2014 if (!allow_duplicates && acpi_video_bus_dev_is_duplicate(dev)) {
2015 pr_info(FW_BUG
2016 "Duplicate ACPI video bus devices for the"
2017 " same VGA controller, please try module "
2018 "parameter \"video.allow_duplicates=1\""
2019 "if the current driver doesn't work.\n");
2020 return -ENODEV;
2021 }
2022
2023 video = kzalloc_obj(struct acpi_video_bus);
2024 if (!video)
2025 return -ENOMEM;
2026
2027 video->device = device;
2028 device->driver_data = video;
2029
2030 error = devm_add_action_or_reset(dev, acpi_video_bus_free, video);
2031 if (error)
2032 return error;
2033
2034 /*
2035 * A hack to fix the duplicate name "VID" problem on T61 and the
2036 * duplicate name "VGA" problem on Pa 3553.
2037 */
2038 if (!strcmp(device->pnp.bus_id, "VID") ||
2039 !strcmp(device->pnp.bus_id, "VGA")) {
2040 if (instance)
2041 device->pnp.bus_id[3] = '0' + instance;
2042
2043 instance++;
2044 }
2045
2046 auxiliary_set_drvdata(aux_dev, video);
2047
2048 acpi_video_bus_find_cap(video);
2049 error = acpi_video_bus_check(video);
2050 if (error)
2051 return error;
2052
2053 mutex_init(&video->device_list_lock);
2054 INIT_LIST_HEAD(&video->video_device_list);
2055
2056 error = devm_acpi_video_bus_get_devices(dev, video);
2057 if (error)
2058 return error;
2059
2060 /*
2061 * HP ZBook Fury 16 G10 requires ACPI video's child devices have _PS0
2062 * evaluated to have functional panel brightness control.
2063 */
2064 acpi_device_fix_up_power_children(device);
2065
2066 pr_info("Video Device [%s] (multi-head: %s rom: %s post: %s)\n",
2067 acpi_device_bid(device), str_yes_no(video->flags.multihead),
2068 str_yes_no(video->flags.rom), str_yes_no(video->flags.post));
2069
2070 /*
2071 * If backlight-type auto-detection is used then a native backlight may
2072 * show up later and this may change the result from video to native.
2073 * Therefor normally the userspace visible /sys/class/backlight device
2074 * gets registered separately by the GPU driver calling
2075 * acpi_video_register_backlight() when an internal panel is detected.
2076 * Register the backlight now when not using auto-detection, so that
2077 * when the kernel cmdline or DMI-quirks are used the backlight will
2078 * get registered even if acpi_video_register_backlight() is not called.
2079 */
2080 acpi_video_run_bcl_for_osi(video);
2081 if (__acpi_video_get_backlight_type(false, &auto_detect) == acpi_backlight_video &&
2082 !auto_detect)
2083 acpi_video_bus_register_backlight(video);
2084
2085 mutex_lock(&video_list_lock);
2086 list_add_tail(&video->entry, &video_bus_head);
2087 mutex_unlock(&video_list_lock);
2088
2089 error = devm_add_action_or_reset(dev, acpi_video_bus_del, video);
2090 if (error)
2091 return error;
2092
2093 error = acpi_video_bus_add_notify_handler(video, dev);
2094 if (error)
2095 return error;
2096
2097 error = devm_add_action_or_reset(dev, acpi_video_bus_remove_notify_handler,
2098 video);
2099 if (error)
2100 return error;
2101
2102 return devm_acpi_install_notify_handler(dev, ACPI_DEVICE_NOTIFY,
2103 acpi_video_bus_notify, video);
2104}
2105
2106static int __init is_i740(struct pci_dev *dev)
2107{
2108 if (dev->device == 0x00D1)
2109 return 1;
2110 if (dev->device == 0x7000)
2111 return 1;
2112 return 0;
2113}
2114
2115static int __init intel_opregion_present(void)
2116{
2117 int opregion = 0;
2118 struct pci_dev *dev = NULL;
2119 u32 address;
2120
2121 for_each_pci_dev(dev) {
2122 if ((dev->class >> 8) != PCI_CLASS_DISPLAY_VGA)
2123 continue;
2124 if (dev->vendor != PCI_VENDOR_ID_INTEL)
2125 continue;
2126 /* We don't want to poke around undefined i740 registers */
2127 if (is_i740(dev))
2128 continue;
2129 pci_read_config_dword(dev, 0xfc, &address);
2130 if (!address)
2131 continue;
2132 opregion = 1;
2133 }
2134 return opregion;
2135}
2136
2137int acpi_video_register(void)
2138{
2139 int ret = 0;
2140
2141 mutex_lock(&register_count_mutex);
2142 if (register_count) {
2143 /*
2144 * if the function of acpi_video_register is already called,
2145 * don't register the acpi_video_bus again and return no error.
2146 */
2147 goto leave;
2148 }
2149
2150 dmi_check_system(video_dmi_table);
2151
2152 ret = auxiliary_driver_register(&acpi_video_bus);
2153 if (ret)
2154 goto leave;
2155
2156 /*
2157 * When the acpi_video_bus is loaded successfully, increase
2158 * the counter reference.
2159 */
2160 register_count = 1;
2161
2162leave:
2163 mutex_unlock(&register_count_mutex);
2164 return ret;
2165}
2166EXPORT_SYMBOL(acpi_video_register);
2167
2168void acpi_video_unregister(void)
2169{
2170 mutex_lock(&register_count_mutex);
2171 if (register_count) {
2172 auxiliary_driver_unregister(&acpi_video_bus);
2173 register_count = 0;
2174 may_report_brightness_keys = false;
2175 }
2176 mutex_unlock(&register_count_mutex);
2177}
2178EXPORT_SYMBOL(acpi_video_unregister);
2179
2180void acpi_video_register_backlight(void)
2181{
2182 struct acpi_video_bus *video;
2183
2184 mutex_lock(&video_list_lock);
2185 list_for_each_entry(video, &video_bus_head, entry)
2186 acpi_video_bus_register_backlight(video);
2187 mutex_unlock(&video_list_lock);
2188}
2189EXPORT_SYMBOL(acpi_video_register_backlight);
2190
2191bool acpi_video_handles_brightness_key_presses(void)
2192{
2193 return may_report_brightness_keys &&
2194 (report_key_events & REPORT_BRIGHTNESS_KEY_EVENTS);
2195}
2196EXPORT_SYMBOL(acpi_video_handles_brightness_key_presses);
2197
2198/*
2199 * This is kind of nasty. Hardware using Intel chipsets may require
2200 * the video opregion code to be run first in order to initialise
2201 * state before any ACPI video calls are made. To handle this we defer
2202 * registration of the video class until the opregion code has run.
2203 */
2204
2205static int __init acpi_video_init(void)
2206{
2207 /*
2208 * Let the module load even if ACPI is disabled (e.g. due to
2209 * a broken BIOS) so that i915.ko can still be loaded on such
2210 * old systems without an AcpiOpRegion.
2211 *
2212 * acpi_video_register() will report -ENODEV later as well due
2213 * to acpi_disabled when i915.ko tries to register itself afterwards.
2214 */
2215 if (acpi_disabled)
2216 return 0;
2217
2218 if (intel_opregion_present())
2219 return 0;
2220
2221 return acpi_video_register();
2222}
2223
2224static void __exit acpi_video_exit(void)
2225{
2226 acpi_video_unregister();
2227}
2228
2229module_init(acpi_video_init);
2230module_exit(acpi_video_exit);