2 * Copyright (C) 2015 Red Hat Inc.
4 * Copyright (C) 2008 SuSE Linux Products GmbH
7 * May be copied or modified under the terms of the GNU General Public License
10 * After PCI devices are glued with ACPI devices
11 * acpi_get_pci_dev() can be called to identify ACPI graphics
12 * devices for which a real graphics card is plugged in
14 * Depending on whether ACPI graphics extensions (cmp. ACPI spec Appendix B)
15 * are available, video.ko should be used to handle the device.
17 * Otherwise vendor specific drivers like thinkpad_acpi, asus-laptop,
18 * sony_acpi,... can take care about backlight brightness.
20 * Backlight drivers can use acpi_video_get_backlight_type() to determine which
21 * driver should handle the backlight. RAW/GPU-driver backlight drivers must
22 * use the acpi_video_backlight_use_native() helper for this.
24 * If CONFIG_ACPI_VIDEO is neither set as "compiled in" (y) nor as a module (m)
25 * this file will not be compiled and acpi_video_get_backlight_type() will
26 * always return acpi_backlight_vendor.
29 #include <linux/export.h>
30 #include <linux/acpi.h>
31 #include <linux/apple-gmux.h>
32 #include <linux/backlight.h>
33 #include <linux/dmi.h>
34 #include <linux/module.h>
35 #include <linux/pci.h>
36 #include <linux/platform_data/x86/nvidia-wmi-ec-backlight.h>
37 #include <linux/pnp.h>
38 #include <linux/types.h>
39 #include <linux/workqueue.h>
40 #include <acpi/video.h>
42 static enum acpi_backlight_type acpi_backlight_cmdline = acpi_backlight_undef;
43 static enum acpi_backlight_type acpi_backlight_dmi = acpi_backlight_undef;
45 static void acpi_video_parse_cmdline(void)
47 if (!strcmp("vendor", acpi_video_backlight_string))
48 acpi_backlight_cmdline = acpi_backlight_vendor;
49 if (!strcmp("video", acpi_video_backlight_string))
50 acpi_backlight_cmdline = acpi_backlight_video;
51 if (!strcmp("native", acpi_video_backlight_string))
52 acpi_backlight_cmdline = acpi_backlight_native;
53 if (!strcmp("nvidia_wmi_ec", acpi_video_backlight_string))
54 acpi_backlight_cmdline = acpi_backlight_nvidia_wmi_ec;
55 if (!strcmp("apple_gmux", acpi_video_backlight_string))
56 acpi_backlight_cmdline = acpi_backlight_apple_gmux;
57 if (!strcmp("none", acpi_video_backlight_string))
58 acpi_backlight_cmdline = acpi_backlight_none;
62 find_video(acpi_handle handle, u32 lvl, void *context, void **rv)
64 struct acpi_device *acpi_dev = acpi_fetch_acpi_dev(handle);
68 static const struct acpi_device_id video_ids[] = {
73 if (acpi_dev && !acpi_match_device_ids(acpi_dev, video_ids)) {
74 dev = acpi_get_pci_dev(handle);
78 *cap |= acpi_is_video_device(handle);
83 /* This depends on ACPI_WMI which is X86 only */
85 static bool nvidia_wmi_ec_supported(void)
87 struct wmi_brightness_args args = {
88 .mode = WMI_BRIGHTNESS_MODE_GET,
92 struct acpi_buffer buf = { (acpi_size)sizeof(args), &args };
95 status = wmi_evaluate_method(WMI_BRIGHTNESS_GUID, 0,
96 WMI_BRIGHTNESS_METHOD_SOURCE, &buf, &buf);
97 if (ACPI_FAILURE(status))
101 * If brightness is handled by the EC then nvidia-wmi-ec-backlight
102 * should be used, else the GPU driver(s) should be used.
104 return args.ret == WMI_BRIGHTNESS_SOURCE_EC;
107 static bool nvidia_wmi_ec_supported(void)
113 /* Force to use vendor driver when the ACPI device is known to be
115 static int video_detect_force_vendor(const struct dmi_system_id *d)
117 acpi_backlight_dmi = acpi_backlight_vendor;
121 static int video_detect_force_video(const struct dmi_system_id *d)
123 acpi_backlight_dmi = acpi_backlight_video;
127 static int video_detect_force_native(const struct dmi_system_id *d)
129 acpi_backlight_dmi = acpi_backlight_native;
133 static const struct dmi_system_id video_detect_dmi_table[] = {
135 * Models which should use the vendor backlight interface,
136 * because of broken ACPI video backlight control.
139 /* https://bugzilla.redhat.com/show_bug.cgi?id=1128309 */
140 .callback = video_detect_force_vendor,
143 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
144 DMI_MATCH(DMI_PRODUCT_NAME, "KAV80"),
148 .callback = video_detect_force_vendor,
151 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
152 DMI_MATCH(DMI_PRODUCT_NAME, "UL30VT"),
156 .callback = video_detect_force_vendor,
159 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
160 DMI_MATCH(DMI_PRODUCT_NAME, "UL30A"),
164 .callback = video_detect_force_vendor,
167 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
168 DMI_MATCH(DMI_PRODUCT_NAME, "X55U"),
172 /* https://bugs.launchpad.net/bugs/1000146 */
173 .callback = video_detect_force_vendor,
176 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
177 DMI_MATCH(DMI_PRODUCT_NAME, "X101CH"),
181 .callback = video_detect_force_vendor,
184 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
185 DMI_MATCH(DMI_PRODUCT_NAME, "X401U"),
189 .callback = video_detect_force_vendor,
192 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
193 DMI_MATCH(DMI_PRODUCT_NAME, "X501U"),
197 /* https://bugs.launchpad.net/bugs/1000146 */
198 .callback = video_detect_force_vendor,
201 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
202 DMI_MATCH(DMI_PRODUCT_NAME, "1015CX"),
206 .callback = video_detect_force_vendor,
207 /* Samsung N150/N210/N220 */
209 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
210 DMI_MATCH(DMI_PRODUCT_NAME, "N150/N210/N220"),
211 DMI_MATCH(DMI_BOARD_NAME, "N150/N210/N220"),
215 .callback = video_detect_force_vendor,
216 /* Samsung NF110/NF210/NF310 */
218 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
219 DMI_MATCH(DMI_PRODUCT_NAME, "NF110/NF210/NF310"),
220 DMI_MATCH(DMI_BOARD_NAME, "NF110/NF210/NF310"),
224 .callback = video_detect_force_vendor,
227 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
228 DMI_MATCH(DMI_PRODUCT_NAME, "NC210/NC110"),
229 DMI_MATCH(DMI_BOARD_NAME, "NC210/NC110"),
233 .callback = video_detect_force_vendor,
234 /* Xiaomi Mi Pad 2 */
236 DMI_MATCH(DMI_SYS_VENDOR, "Xiaomi Inc"),
237 DMI_MATCH(DMI_PRODUCT_NAME, "Mipad2"),
242 * Models which should use the vendor backlight interface,
243 * because of broken native backlight control.
246 .callback = video_detect_force_vendor,
247 /* Sony Vaio PCG-FRV35 */
249 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
250 DMI_MATCH(DMI_PRODUCT_NAME, "PCG-FRV35"),
255 * Toshiba models with Transflective display, these need to use
256 * the toshiba_acpi vendor driver for proper Transflective handling.
259 .callback = video_detect_force_vendor,
261 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
262 DMI_MATCH(DMI_PRODUCT_NAME, "PORTEGE R500"),
266 .callback = video_detect_force_vendor,
268 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
269 DMI_MATCH(DMI_PRODUCT_NAME, "PORTEGE R600"),
274 * Models which need acpi_video backlight control where the GPU drivers
275 * do not call acpi_video_register_backlight() because no internal panel
276 * is detected. Typically these are all-in-ones (monitors with builtin
277 * PC) where the panel connection shows up as regular DP instead of eDP.
280 .callback = video_detect_force_video,
283 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
284 DMI_MATCH(DMI_PRODUCT_NAME, "iMac14,1"),
288 .callback = video_detect_force_video,
291 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
292 DMI_MATCH(DMI_PRODUCT_NAME, "iMac14,2"),
297 * These models have a working acpi_video backlight control, and using
298 * native backlight causes a regression where backlight does not work
299 * when userspace is not handling brightness key events. Disable
300 * native_backlight on these to fix this:
301 * https://bugzilla.kernel.org/show_bug.cgi?id=81691
304 .callback = video_detect_force_video,
307 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
308 DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T420"),
312 .callback = video_detect_force_video,
315 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
316 DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T520"),
320 .callback = video_detect_force_video,
323 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
324 DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X201s"),
328 .callback = video_detect_force_video,
331 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
332 DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X201T"),
336 /* The native backlight controls do not work on some older machines */
338 /* https://bugs.freedesktop.org/show_bug.cgi?id=81515 */
339 .callback = video_detect_force_video,
340 /* HP ENVY 15 Notebook */
342 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
343 DMI_MATCH(DMI_PRODUCT_NAME, "HP ENVY 15 Notebook PC"),
347 .callback = video_detect_force_video,
348 /* SAMSUNG 870Z5E/880Z5E/680Z5E */
350 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
351 DMI_MATCH(DMI_PRODUCT_NAME, "870Z5E/880Z5E/680Z5E"),
355 .callback = video_detect_force_video,
356 /* SAMSUNG 370R4E/370R4V/370R5E/3570RE/370R5V */
358 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
359 DMI_MATCH(DMI_PRODUCT_NAME,
360 "370R4E/370R4V/370R5E/3570RE/370R5V"),
364 /* https://bugzilla.redhat.com/show_bug.cgi?id=1186097 */
365 .callback = video_detect_force_video,
366 /* SAMSUNG 3570R/370R/470R/450R/510R/4450RV */
368 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
369 DMI_MATCH(DMI_PRODUCT_NAME,
370 "3570R/370R/470R/450R/510R/4450RV"),
374 /* https://bugzilla.redhat.com/show_bug.cgi?id=1557060 */
375 .callback = video_detect_force_video,
378 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
379 DMI_MATCH(DMI_PRODUCT_NAME, "670Z5E"),
383 /* https://bugzilla.redhat.com/show_bug.cgi?id=1094948 */
384 .callback = video_detect_force_video,
385 /* SAMSUNG 730U3E/740U3E */
387 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
388 DMI_MATCH(DMI_PRODUCT_NAME, "730U3E/740U3E"),
392 /* https://bugs.freedesktop.org/show_bug.cgi?id=87286 */
393 .callback = video_detect_force_video,
394 /* SAMSUNG 900X3C/900X3D/900X3E/900X4C/900X4D */
396 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
397 DMI_MATCH(DMI_PRODUCT_NAME,
398 "900X3C/900X3D/900X3E/900X4C/900X4D"),
402 /* https://bugzilla.redhat.com/show_bug.cgi?id=1272633 */
403 .callback = video_detect_force_video,
404 /* Dell XPS14 L421X */
406 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
407 DMI_MATCH(DMI_PRODUCT_NAME, "XPS L421X"),
411 /* https://bugzilla.redhat.com/show_bug.cgi?id=1163574 */
412 .callback = video_detect_force_video,
413 /* Dell XPS15 L521X */
415 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
416 DMI_MATCH(DMI_PRODUCT_NAME, "XPS L521X"),
420 /* https://bugzilla.kernel.org/show_bug.cgi?id=108971 */
421 .callback = video_detect_force_video,
422 /* SAMSUNG 530U4E/540U4E */
424 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
425 DMI_MATCH(DMI_PRODUCT_NAME, "530U4E/540U4E"),
429 /* https://bugs.launchpad.net/bugs/1894667 */
430 .callback = video_detect_force_video,
431 /* HP 635 Notebook */
433 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
434 DMI_MATCH(DMI_PRODUCT_NAME, "HP 635 Notebook PC"),
438 /* Non win8 machines which need native backlight nevertheless */
440 /* https://bugzilla.redhat.com/show_bug.cgi?id=1201530 */
441 .callback = video_detect_force_native,
442 /* Lenovo Ideapad S405 */
444 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
445 DMI_MATCH(DMI_BOARD_NAME, "Lenovo IdeaPad S405"),
449 /* https://bugzilla.redhat.com/show_bug.cgi?id=1187004 */
450 .callback = video_detect_force_native,
451 /* Lenovo Ideapad Z570 */
453 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
454 DMI_MATCH(DMI_PRODUCT_VERSION, "Ideapad Z570"),
458 .callback = video_detect_force_native,
461 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
462 DMI_MATCH(DMI_PRODUCT_NAME, "81FS"),
466 .callback = video_detect_force_native,
469 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
470 DMI_MATCH(DMI_PRODUCT_NAME, "82BK"),
474 .callback = video_detect_force_native,
475 /* Lenovo ThinkPad X131e (3371 AMD version) */
477 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
478 DMI_MATCH(DMI_PRODUCT_NAME, "3371"),
482 .callback = video_detect_force_native,
485 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
486 DMI_MATCH(DMI_PRODUCT_NAME, "iMac11,3"),
490 /* https://bugzilla.redhat.com/show_bug.cgi?id=1217249 */
491 .callback = video_detect_force_native,
492 /* Apple MacBook Pro 12,1 */
494 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
495 DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro12,1"),
499 .callback = video_detect_force_native,
500 /* Dell Inspiron N4010 */
502 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
503 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron N4010"),
507 .callback = video_detect_force_native,
508 /* Dell Vostro V131 */
510 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
511 DMI_MATCH(DMI_PRODUCT_NAME, "Vostro V131"),
515 /* https://bugzilla.redhat.com/show_bug.cgi?id=1123661 */
516 .callback = video_detect_force_native,
517 /* Dell XPS 17 L702X */
519 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
520 DMI_MATCH(DMI_PRODUCT_NAME, "Dell System XPS L702X"),
524 .callback = video_detect_force_native,
525 /* Dell Precision 7510 */
527 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
528 DMI_MATCH(DMI_PRODUCT_NAME, "Precision 7510"),
532 .callback = video_detect_force_native,
533 /* Dell Studio 1569 */
535 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
536 DMI_MATCH(DMI_PRODUCT_NAME, "Studio 1569"),
540 .callback = video_detect_force_native,
541 /* Acer Aspire 3830TG */
543 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
544 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 3830TG"),
548 .callback = video_detect_force_native,
549 /* Acer Aspire 4810T */
551 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
552 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 4810T"),
556 .callback = video_detect_force_native,
557 /* Acer Aspire 5738z */
559 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
560 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5738"),
561 DMI_MATCH(DMI_BOARD_NAME, "JV50"),
565 /* https://bugzilla.redhat.com/show_bug.cgi?id=1012674 */
566 .callback = video_detect_force_native,
567 /* Acer Aspire 5741 */
569 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
570 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5741"),
574 /* https://bugzilla.kernel.org/show_bug.cgi?id=42993 */
575 .callback = video_detect_force_native,
576 /* Acer Aspire 5750 */
578 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
579 DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5750"),
583 /* https://bugzilla.kernel.org/show_bug.cgi?id=42833 */
584 .callback = video_detect_force_native,
585 /* Acer Extensa 5235 */
587 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
588 DMI_MATCH(DMI_PRODUCT_NAME, "Extensa 5235"),
592 .callback = video_detect_force_native,
593 /* Acer TravelMate 4750 */
595 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
596 DMI_MATCH(DMI_PRODUCT_NAME, "TravelMate 4750"),
600 /* https://bugzilla.kernel.org/show_bug.cgi?id=207835 */
601 .callback = video_detect_force_native,
602 /* Acer TravelMate 5735Z */
604 DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
605 DMI_MATCH(DMI_PRODUCT_NAME, "TravelMate 5735Z"),
606 DMI_MATCH(DMI_BOARD_NAME, "BA51_MV"),
610 /* https://bugzilla.kernel.org/show_bug.cgi?id=36322 */
611 .callback = video_detect_force_native,
612 /* Acer TravelMate 5760 */
614 DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
615 DMI_MATCH(DMI_PRODUCT_NAME, "TravelMate 5760"),
619 .callback = video_detect_force_native,
620 /* ASUSTeK COMPUTER INC. GA401 */
622 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
623 DMI_MATCH(DMI_PRODUCT_NAME, "GA401"),
627 .callback = video_detect_force_native,
628 /* ASUSTeK COMPUTER INC. GA502 */
630 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
631 DMI_MATCH(DMI_PRODUCT_NAME, "GA502"),
635 .callback = video_detect_force_native,
636 /* ASUSTeK COMPUTER INC. GA503 */
638 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
639 DMI_MATCH(DMI_PRODUCT_NAME, "GA503"),
643 .callback = video_detect_force_native,
646 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
647 DMI_MATCH(DMI_PRODUCT_NAME, "U46E"),
651 .callback = video_detect_force_native,
654 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
655 DMI_MATCH(DMI_PRODUCT_NAME, "UX303UB"),
659 .callback = video_detect_force_native,
660 /* HP EliteBook 8460p */
662 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
663 DMI_MATCH(DMI_PRODUCT_NAME, "HP EliteBook 8460p"),
667 .callback = video_detect_force_native,
668 /* HP Pavilion g6-1d80nr / B4U19UA */
670 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
671 DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion g6 Notebook PC"),
672 DMI_MATCH(DMI_PRODUCT_SKU, "B4U19UA"),
676 .callback = video_detect_force_native,
679 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
680 DMI_MATCH(DMI_PRODUCT_NAME, "N150P"),
681 DMI_MATCH(DMI_BOARD_NAME, "N150P"),
685 .callback = video_detect_force_native,
686 /* Samsung N145P/N250P/N260P */
688 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
689 DMI_MATCH(DMI_PRODUCT_NAME, "N145P/N250P/N260P"),
690 DMI_MATCH(DMI_BOARD_NAME, "N145P/N250P/N260P"),
694 .callback = video_detect_force_native,
697 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
698 DMI_MATCH(DMI_PRODUCT_NAME, "N250P"),
699 DMI_MATCH(DMI_BOARD_NAME, "N250P"),
703 /* https://bugzilla.kernel.org/show_bug.cgi?id=202401 */
704 .callback = video_detect_force_native,
705 /* Sony Vaio VPCEH3U1E */
707 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
708 DMI_MATCH(DMI_PRODUCT_NAME, "VPCEH3U1E"),
712 .callback = video_detect_force_native,
713 /* Sony Vaio VPCY11S1E */
715 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
716 DMI_MATCH(DMI_PRODUCT_NAME, "VPCY11S1E"),
721 * These Toshibas have a broken acpi-video interface for brightness
722 * control. They also have an issue where the panel is off after
723 * suspend until a special firmware call is made to turn it back
724 * on. This is handled by the toshiba_acpi kernel module, so that
725 * module must be enabled for these models to work correctly.
728 /* https://bugzilla.kernel.org/show_bug.cgi?id=21012 */
729 .callback = video_detect_force_native,
730 /* Toshiba Portégé R700 */
732 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
733 DMI_MATCH(DMI_PRODUCT_NAME, "PORTEGE R700"),
737 /* Portégé: https://bugs.freedesktop.org/show_bug.cgi?id=82634 */
738 /* Satellite: https://bugzilla.kernel.org/show_bug.cgi?id=21012 */
739 .callback = video_detect_force_native,
740 /* Toshiba Satellite/Portégé R830 */
742 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
743 DMI_MATCH(DMI_PRODUCT_NAME, "R830"),
747 .callback = video_detect_force_native,
748 /* Toshiba Satellite/Portégé Z830 */
750 DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
751 DMI_MATCH(DMI_PRODUCT_NAME, "Z830"),
756 * Models which have nvidia-ec-wmi support, but should not use it.
757 * Note this indicates a likely firmware bug on these models and should
758 * be revisited if/when Linux gets support for dynamic mux mode.
761 .callback = video_detect_force_native,
764 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
765 DMI_MATCH(DMI_PRODUCT_NAME, "Dell G15 5515"),
769 .callback = video_detect_force_native,
771 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
772 DMI_MATCH(DMI_PRODUCT_NAME, "Vostro 15 3535"),
778 static bool google_cros_ec_present(void)
780 return acpi_dev_found("GOOG0004") || acpi_dev_found("GOOG000C");
784 * Windows 8 and newer no longer use the ACPI video interface, so it often
785 * does not work. So on win8+ systems prefer native brightness control.
786 * Chromebooks should always prefer native backlight control.
788 static bool prefer_native_over_acpi_video(void)
790 return acpi_osi_is_win8() || google_cros_ec_present();
794 * Determine which type of backlight interface to use on this system,
795 * First check cmdline, then dmi quirks, then do autodetect.
797 enum acpi_backlight_type __acpi_video_get_backlight_type(bool native, bool *auto_detect)
799 static DEFINE_MUTEX(init_mutex);
800 static bool nvidia_wmi_ec_present;
801 static bool apple_gmux_present;
802 static bool native_available;
803 static bool init_done;
804 static long video_caps;
806 /* Parse cmdline, dmi and acpi only once */
807 mutex_lock(&init_mutex);
809 acpi_video_parse_cmdline();
810 dmi_check_system(video_detect_dmi_table);
811 acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
812 ACPI_UINT32_MAX, find_video, NULL,
814 nvidia_wmi_ec_present = nvidia_wmi_ec_supported();
815 apple_gmux_present = apple_gmux_detect(NULL, NULL);
819 native_available = true;
820 mutex_unlock(&init_mutex);
823 *auto_detect = false;
826 * The below heuristics / detection steps are in order of descending
827 * presedence. The commandline takes presedence over anything else.
829 if (acpi_backlight_cmdline != acpi_backlight_undef)
830 return acpi_backlight_cmdline;
832 /* DMI quirks override any autodetection. */
833 if (acpi_backlight_dmi != acpi_backlight_undef)
834 return acpi_backlight_dmi;
839 /* Special cases such as nvidia_wmi_ec and apple gmux. */
840 if (nvidia_wmi_ec_present)
841 return acpi_backlight_nvidia_wmi_ec;
843 if (apple_gmux_present)
844 return acpi_backlight_apple_gmux;
846 /* Use ACPI video if available, except when native should be preferred. */
847 if ((video_caps & ACPI_VIDEO_BACKLIGHT) &&
848 !(native_available && prefer_native_over_acpi_video()))
849 return acpi_backlight_video;
851 /* Use native if available */
852 if (native_available)
853 return acpi_backlight_native;
856 * The vendor specific BIOS interfaces are only necessary for
857 * laptops from before ~2008.
859 * For laptops from ~2008 till ~2023 this point is never reached
860 * because on those (video_caps & ACPI_VIDEO_BACKLIGHT) above is true.
862 * Laptops from after ~2023 no longer support ACPI_VIDEO_BACKLIGHT,
863 * if this point is reached on those, this likely means that
864 * the GPU kms driver which sets native_available has not loaded yet.
866 * Returning acpi_backlight_vendor in this case is known to sometimes
867 * cause a non working vendor specific /sys/class/backlight device to
870 * Return acpi_backlight_none on laptops with ACPI tables written
871 * for Windows 8 (laptops from after ~2012) to avoid this problem.
873 if (acpi_osi_is_win8())
874 return acpi_backlight_none;
876 /* No ACPI video/native (old hw), use vendor specific fw methods. */
877 return acpi_backlight_vendor;
879 EXPORT_SYMBOL(__acpi_video_get_backlight_type);