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1 /*
2  *  Copyright (C) 2015       Red Hat Inc.
3  *                           Hans de Goede <hdegoede@redhat.com>
4  *  Copyright (C) 2008       SuSE Linux Products GmbH
5  *                           Thomas Renninger <trenn@suse.de>
6  *
7  *  May be copied or modified under the terms of the GNU General Public License
8  *
9  * video_detect.c:
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
13  *
14  * Depending on whether ACPI graphics extensions (cmp. ACPI spec Appendix B)
15  * are available, video.ko should be used to handle the device.
16  *
17  * Otherwise vendor specific drivers like thinkpad_acpi, asus-laptop,
18  * sony_acpi,... can take care about backlight brightness.
19  *
20  * Backlight drivers can use acpi_video_get_backlight_type() to determine
21  * which driver should handle the backlight.
22  *
23  * If CONFIG_ACPI_VIDEO is neither set as "compiled in" (y) nor as a module (m)
24  * this file will not be compiled and acpi_video_get_backlight_type() will
25  * always return acpi_backlight_vendor.
26  */
27 
28 #include <linux/export.h>
29 #include <linux/acpi.h>
30 #include <linux/backlight.h>
31 #include <linux/dmi.h>
32 #include <linux/module.h>
33 #include <linux/pci.h>
34 #include <linux/types.h>
35 #include <linux/workqueue.h>
36 #include <acpi/video.h>
37 
38 void acpi_video_unregister_backlight(void);
39 
40 static bool backlight_notifier_registered;
41 static struct notifier_block backlight_nb;
42 static struct work_struct backlight_notify_work;
43 
44 static enum acpi_backlight_type acpi_backlight_cmdline = acpi_backlight_undef;
45 static enum acpi_backlight_type acpi_backlight_dmi = acpi_backlight_undef;
46 
acpi_video_parse_cmdline(void)47 static void acpi_video_parse_cmdline(void)
48 {
49 	if (!strcmp("vendor", acpi_video_backlight_string))
50 		acpi_backlight_cmdline = acpi_backlight_vendor;
51 	if (!strcmp("video", acpi_video_backlight_string))
52 		acpi_backlight_cmdline = acpi_backlight_video;
53 	if (!strcmp("native", acpi_video_backlight_string))
54 		acpi_backlight_cmdline = acpi_backlight_native;
55 	if (!strcmp("none", acpi_video_backlight_string))
56 		acpi_backlight_cmdline = acpi_backlight_none;
57 }
58 
59 static acpi_status
find_video(acpi_handle handle,u32 lvl,void * context,void ** rv)60 find_video(acpi_handle handle, u32 lvl, void *context, void **rv)
61 {
62 	long *cap = context;
63 	struct pci_dev *dev;
64 	struct acpi_device *acpi_dev;
65 
66 	static const struct acpi_device_id video_ids[] = {
67 		{ACPI_VIDEO_HID, 0},
68 		{"", 0},
69 	};
70 	if (acpi_bus_get_device(handle, &acpi_dev))
71 		return AE_OK;
72 
73 	if (!acpi_match_device_ids(acpi_dev, video_ids)) {
74 		dev = acpi_get_pci_dev(handle);
75 		if (!dev)
76 			return AE_OK;
77 		pci_dev_put(dev);
78 		*cap |= acpi_is_video_device(handle);
79 	}
80 	return AE_OK;
81 }
82 
83 /* Force to use vendor driver when the ACPI device is known to be
84  * buggy */
video_detect_force_vendor(const struct dmi_system_id * d)85 static int video_detect_force_vendor(const struct dmi_system_id *d)
86 {
87 	acpi_backlight_dmi = acpi_backlight_vendor;
88 	return 0;
89 }
90 
video_detect_force_video(const struct dmi_system_id * d)91 static int video_detect_force_video(const struct dmi_system_id *d)
92 {
93 	acpi_backlight_dmi = acpi_backlight_video;
94 	return 0;
95 }
96 
video_detect_force_native(const struct dmi_system_id * d)97 static int video_detect_force_native(const struct dmi_system_id *d)
98 {
99 	acpi_backlight_dmi = acpi_backlight_native;
100 	return 0;
101 }
102 
video_detect_force_none(const struct dmi_system_id * d)103 static int video_detect_force_none(const struct dmi_system_id *d)
104 {
105 	acpi_backlight_dmi = acpi_backlight_none;
106 	return 0;
107 }
108 
109 static const struct dmi_system_id video_detect_dmi_table[] = {
110 	/* On Samsung X360, the BIOS will set a flag (VDRV) if generic
111 	 * ACPI backlight device is used. This flag will definitively break
112 	 * the backlight interface (even the vendor interface) until next
113 	 * reboot. It's why we should prevent video.ko from being used here
114 	 * and we can't rely on a later call to acpi_video_unregister().
115 	 */
116 	{
117 	 .callback = video_detect_force_vendor,
118 	 .ident = "X360",
119 	 .matches = {
120 		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
121 		DMI_MATCH(DMI_PRODUCT_NAME, "X360"),
122 		DMI_MATCH(DMI_BOARD_NAME, "X360"),
123 		},
124 	},
125 	{
126 	.callback = video_detect_force_vendor,
127 	.ident = "Asus UL30VT",
128 	.matches = {
129 		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
130 		DMI_MATCH(DMI_PRODUCT_NAME, "UL30VT"),
131 		},
132 	},
133 	{
134 	.callback = video_detect_force_vendor,
135 	.ident = "Asus UL30A",
136 	.matches = {
137 		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
138 		DMI_MATCH(DMI_PRODUCT_NAME, "UL30A"),
139 		},
140 	},
141 	{
142 	.callback = video_detect_force_vendor,
143 	.ident = "GIGABYTE GB-BXBT-2807",
144 	.matches = {
145 		DMI_MATCH(DMI_SYS_VENDOR, "GIGABYTE"),
146 		DMI_MATCH(DMI_PRODUCT_NAME, "GB-BXBT-2807"),
147 		},
148 	},
149 	{
150 	.callback = video_detect_force_vendor,
151 	.ident = "Sony VPCEH3U1E",
152 	.matches = {
153 		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
154 		DMI_MATCH(DMI_PRODUCT_NAME, "VPCEH3U1E"),
155 		},
156 	},
157 
158 	/*
159 	 * These models have a working acpi_video backlight control, and using
160 	 * native backlight causes a regression where backlight does not work
161 	 * when userspace is not handling brightness key events. Disable
162 	 * native_backlight on these to fix this:
163 	 * https://bugzilla.kernel.org/show_bug.cgi?id=81691
164 	 */
165 	{
166 	 .callback = video_detect_force_video,
167 	 .ident = "ThinkPad T420",
168 	 .matches = {
169 		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
170 		DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T420"),
171 		},
172 	},
173 	{
174 	 .callback = video_detect_force_video,
175 	 .ident = "ThinkPad T520",
176 	 .matches = {
177 		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
178 		DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T520"),
179 		},
180 	},
181 	{
182 	 .callback = video_detect_force_video,
183 	 .ident = "ThinkPad X201s",
184 	 .matches = {
185 		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
186 		DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X201s"),
187 		},
188 	},
189 	{
190 	 .callback = video_detect_force_video,
191 	 .ident = "ThinkPad X201T",
192 	 .matches = {
193 		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
194 		DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X201T"),
195 		},
196 	},
197 
198 	/* The native backlight controls do not work on some older machines */
199 	{
200 	 /* https://bugs.freedesktop.org/show_bug.cgi?id=81515 */
201 	 .callback = video_detect_force_video,
202 	 .ident = "HP ENVY 15 Notebook",
203 	 .matches = {
204 		DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
205 		DMI_MATCH(DMI_PRODUCT_NAME, "HP ENVY 15 Notebook PC"),
206 		},
207 	},
208 	{
209 	 .callback = video_detect_force_video,
210 	 .ident = "SAMSUNG 870Z5E/880Z5E/680Z5E",
211 	 .matches = {
212 		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
213 		DMI_MATCH(DMI_PRODUCT_NAME, "870Z5E/880Z5E/680Z5E"),
214 		},
215 	},
216 	{
217 	 .callback = video_detect_force_video,
218 	 .ident = "SAMSUNG 370R4E/370R4V/370R5E/3570RE/370R5V",
219 	 .matches = {
220 		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
221 		DMI_MATCH(DMI_PRODUCT_NAME,
222 			  "370R4E/370R4V/370R5E/3570RE/370R5V"),
223 		},
224 	},
225 	{
226 	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1186097 */
227 	 .callback = video_detect_force_video,
228 	 .ident = "SAMSUNG 3570R/370R/470R/450R/510R/4450RV",
229 	 .matches = {
230 		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
231 		DMI_MATCH(DMI_PRODUCT_NAME,
232 			  "3570R/370R/470R/450R/510R/4450RV"),
233 		},
234 	},
235 	{
236 	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1557060 */
237 	 .callback = video_detect_force_video,
238 	 .ident = "SAMSUNG 670Z5E",
239 	 .matches = {
240 		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
241 		DMI_MATCH(DMI_PRODUCT_NAME, "670Z5E"),
242 		},
243 	},
244 	{
245 	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1094948 */
246 	 .callback = video_detect_force_video,
247 	 .ident = "SAMSUNG 730U3E/740U3E",
248 	 .matches = {
249 		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
250 		DMI_MATCH(DMI_PRODUCT_NAME, "730U3E/740U3E"),
251 		},
252 	},
253 	{
254 	 /* https://bugs.freedesktop.org/show_bug.cgi?id=87286 */
255 	 .callback = video_detect_force_video,
256 	 .ident = "SAMSUNG 900X3C/900X3D/900X3E/900X4C/900X4D",
257 	 .matches = {
258 		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
259 		DMI_MATCH(DMI_PRODUCT_NAME,
260 			  "900X3C/900X3D/900X3E/900X4C/900X4D"),
261 		},
262 	},
263 	{
264 	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1272633 */
265 	 .callback = video_detect_force_video,
266 	 .ident = "Dell XPS14 L421X",
267 	 .matches = {
268 		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
269 		DMI_MATCH(DMI_PRODUCT_NAME, "XPS L421X"),
270 		},
271 	},
272 	{
273 	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1163574 */
274 	 .callback = video_detect_force_video,
275 	 .ident = "Dell XPS15 L521X",
276 	 .matches = {
277 		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
278 		DMI_MATCH(DMI_PRODUCT_NAME, "XPS L521X"),
279 		},
280 	},
281 	{
282 	 /* https://bugzilla.kernel.org/show_bug.cgi?id=108971 */
283 	 .callback = video_detect_force_video,
284 	 .ident = "SAMSUNG 530U4E/540U4E",
285 	 .matches = {
286 		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
287 		DMI_MATCH(DMI_PRODUCT_NAME, "530U4E/540U4E"),
288 		},
289 	},
290 	/* https://bugs.launchpad.net/bugs/1894667 */
291 	{
292 	 .callback = video_detect_force_video,
293 	 .ident = "HP 635 Notebook",
294 	 .matches = {
295 		DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
296 		DMI_MATCH(DMI_PRODUCT_NAME, "HP 635 Notebook PC"),
297 		},
298 	},
299 
300 	/* Non win8 machines which need native backlight nevertheless */
301 	{
302 	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1201530 */
303 	 .callback = video_detect_force_native,
304 	 .ident = "Lenovo Ideapad S405",
305 	 .matches = {
306 		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
307 		DMI_MATCH(DMI_BOARD_NAME, "Lenovo IdeaPad S405"),
308 		},
309 	},
310 	{
311 	 /* https://bugzilla.suse.com/show_bug.cgi?id=1208724 */
312 	 .callback = video_detect_force_native,
313 	 /* Lenovo Ideapad Z470 */
314 	 .matches = {
315 		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
316 		DMI_MATCH(DMI_PRODUCT_VERSION, "IdeaPad Z470"),
317 		},
318 	},
319 	{
320 	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1187004 */
321 	 .callback = video_detect_force_native,
322 	 .ident = "Lenovo Ideapad Z570",
323 	 .matches = {
324 		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
325 		DMI_MATCH(DMI_PRODUCT_VERSION, "Ideapad Z570"),
326 		},
327 	},
328 	{
329 	 .callback = video_detect_force_native,
330 	 .ident = "Lenovo E41-25",
331 	 .matches = {
332 		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
333 		DMI_MATCH(DMI_PRODUCT_NAME, "81FS"),
334 		},
335 	},
336 	{
337 	 .callback = video_detect_force_native,
338 	 .ident = "Lenovo E41-45",
339 	 .matches = {
340 		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
341 		DMI_MATCH(DMI_PRODUCT_NAME, "82BK"),
342 		},
343 	},
344 	{
345 	 .callback = video_detect_force_native,
346 	 /* Lenovo ThinkPad X131e (3371 AMD version) */
347 	 .matches = {
348 		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
349 		DMI_MATCH(DMI_PRODUCT_NAME, "3371"),
350 		},
351 	},
352 	{
353 	 .callback = video_detect_force_native,
354 	 /* Apple iMac11,3 */
355 	 .matches = {
356 		DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
357 		DMI_MATCH(DMI_PRODUCT_NAME, "iMac11,3"),
358 		},
359 	},
360 	{
361 	 /* https://gitlab.freedesktop.org/drm/amd/-/issues/1838 */
362 	 .callback = video_detect_force_native,
363 	 /* Apple iMac12,1 */
364 	 .matches = {
365 		DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
366 		DMI_MATCH(DMI_PRODUCT_NAME, "iMac12,1"),
367 		},
368 	},
369 	{
370 	 /* https://gitlab.freedesktop.org/drm/amd/-/issues/2753 */
371 	 .callback = video_detect_force_native,
372 	 /* Apple iMac12,2 */
373 	 .matches = {
374 		DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
375 		DMI_MATCH(DMI_PRODUCT_NAME, "iMac12,2"),
376 		},
377 	},
378 	{
379 	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1217249 */
380 	 .callback = video_detect_force_native,
381 	 .ident = "Apple MacBook Pro 12,1",
382 	 .matches = {
383 		DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
384 		DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro12,1"),
385 		},
386 	},
387 	{
388 	 .callback = video_detect_force_native,
389 	 .ident = "Dell Vostro V131",
390 	 .matches = {
391 		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
392 		DMI_MATCH(DMI_PRODUCT_NAME, "Vostro V131"),
393 		},
394 	},
395 	{
396 	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1123661 */
397 	 .callback = video_detect_force_native,
398 	 .ident = "Dell XPS 17 L702X",
399 	 .matches = {
400 		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
401 		DMI_MATCH(DMI_PRODUCT_NAME, "Dell System XPS L702X"),
402 		},
403 	},
404 	{
405 	 .callback = video_detect_force_native,
406 	 .ident = "Dell Precision 7510",
407 	 .matches = {
408 		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
409 		DMI_MATCH(DMI_PRODUCT_NAME, "Precision 7510"),
410 		},
411 	},
412 	{
413 	 .callback = video_detect_force_native,
414 	 .ident = "Acer Aspire 5738z",
415 	 .matches = {
416 		DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
417 		DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5738"),
418 		DMI_MATCH(DMI_BOARD_NAME, "JV50"),
419 		},
420 	},
421 	{
422 	 /* https://bugzilla.kernel.org/show_bug.cgi?id=207835 */
423 	 .callback = video_detect_force_native,
424 	 .ident = "Acer TravelMate 5735Z",
425 	 .matches = {
426 		DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
427 		DMI_MATCH(DMI_PRODUCT_NAME, "TravelMate 5735Z"),
428 		DMI_MATCH(DMI_BOARD_NAME, "BA51_MV"),
429 		},
430 	},
431 	{
432 	.callback = video_detect_force_native,
433 	.ident = "ASUSTeK COMPUTER INC. GA401",
434 	.matches = {
435 		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
436 		DMI_MATCH(DMI_PRODUCT_NAME, "GA401"),
437 		},
438 	},
439 	{
440 	.callback = video_detect_force_native,
441 	.ident = "ASUSTeK COMPUTER INC. GA502",
442 	.matches = {
443 		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
444 		DMI_MATCH(DMI_PRODUCT_NAME, "GA502"),
445 		},
446 	},
447 	{
448 	.callback = video_detect_force_native,
449 	.ident = "ASUSTeK COMPUTER INC. GA503",
450 	.matches = {
451 		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
452 		DMI_MATCH(DMI_PRODUCT_NAME, "GA503"),
453 		},
454 	},
455 	/*
456 	 * Clevo NL5xRU and NL5xNU/TUXEDO Aura 15 Gen1 and Gen2 have both a
457 	 * working native and video interface. However the default detection
458 	 * mechanism first registers the video interface before unregistering
459 	 * it again and switching to the native interface during boot. This
460 	 * results in a dangling SBIOS request for backlight change for some
461 	 * reason, causing the backlight to switch to ~2% once per boot on the
462 	 * first power cord connect or disconnect event. Setting the native
463 	 * interface explicitly circumvents this buggy behaviour, by avoiding
464 	 * the unregistering process.
465 	 */
466 	{
467 	.callback = video_detect_force_native,
468 	.ident = "Clevo NL5xRU",
469 	.matches = {
470 		DMI_MATCH(DMI_BOARD_NAME, "NL5xRU"),
471 		},
472 	},
473 	{
474 	.callback = video_detect_force_native,
475 	.ident = "Clevo NL5xRU",
476 	.matches = {
477 		DMI_MATCH(DMI_SYS_VENDOR, "TUXEDO"),
478 		DMI_MATCH(DMI_BOARD_NAME, "AURA1501"),
479 		},
480 	},
481 	{
482 	.callback = video_detect_force_native,
483 	.ident = "Clevo NL5xRU",
484 	.matches = {
485 		DMI_MATCH(DMI_SYS_VENDOR, "TUXEDO"),
486 		DMI_MATCH(DMI_BOARD_NAME, "EDUBOOK1502"),
487 		},
488 	},
489 	{
490 	.callback = video_detect_force_native,
491 	.ident = "Clevo NL5xNU",
492 	.matches = {
493 		DMI_MATCH(DMI_BOARD_NAME, "NL5xNU"),
494 		},
495 	},
496 	/*
497 	 * The TongFang PF5PU1G, PF4NU1F, PF5NU1G, and PF5LUXG/TUXEDO BA15 Gen10,
498 	 * Pulse 14/15 Gen1, and Pulse 15 Gen2 have the same problem as the Clevo
499 	 * NL5xRU and NL5xNU/TUXEDO Aura 15 Gen1 and Gen2. See the description
500 	 * above.
501 	 */
502 	{
503 	.callback = video_detect_force_native,
504 	.ident = "TongFang PF5PU1G",
505 	.matches = {
506 		DMI_MATCH(DMI_BOARD_NAME, "PF5PU1G"),
507 		},
508 	},
509 	{
510 	.callback = video_detect_force_native,
511 	.ident = "TongFang PF4NU1F",
512 	.matches = {
513 		DMI_MATCH(DMI_BOARD_NAME, "PF4NU1F"),
514 		},
515 	},
516 	{
517 	.callback = video_detect_force_native,
518 	.ident = "TongFang PF4NU1F",
519 	.matches = {
520 		DMI_MATCH(DMI_SYS_VENDOR, "TUXEDO"),
521 		DMI_MATCH(DMI_BOARD_NAME, "PULSE1401"),
522 		},
523 	},
524 	{
525 	.callback = video_detect_force_native,
526 	.ident = "TongFang PF5NU1G",
527 	.matches = {
528 		DMI_MATCH(DMI_BOARD_NAME, "PF5NU1G"),
529 		},
530 	},
531 	{
532 	.callback = video_detect_force_native,
533 	.ident = "TongFang PF5NU1G",
534 	.matches = {
535 		DMI_MATCH(DMI_SYS_VENDOR, "TUXEDO"),
536 		DMI_MATCH(DMI_BOARD_NAME, "PULSE1501"),
537 		},
538 	},
539 	{
540 	.callback = video_detect_force_native,
541 	.ident = "TongFang PF5LUXG",
542 	.matches = {
543 		DMI_MATCH(DMI_BOARD_NAME, "PF5LUXG"),
544 		},
545 	},
546 	/*
547 	 * More Tongfang devices with the same issue as the Clevo NL5xRU and
548 	 * NL5xNU/TUXEDO Aura 15 Gen1 and Gen2. See the description above.
549 	 */
550 	{
551 	.callback = video_detect_force_native,
552 	.ident = "TongFang GKxNRxx",
553 	.matches = {
554 		DMI_MATCH(DMI_BOARD_NAME, "GKxNRxx"),
555 		},
556 	},
557 	{
558 	.callback = video_detect_force_native,
559 	.ident = "TongFang GKxNRxx",
560 	.matches = {
561 		DMI_MATCH(DMI_SYS_VENDOR, "TUXEDO"),
562 		DMI_MATCH(DMI_BOARD_NAME, "POLARIS1501A1650TI"),
563 		},
564 	},
565 	{
566 	.callback = video_detect_force_native,
567 	.ident = "TongFang GKxNRxx",
568 	.matches = {
569 		DMI_MATCH(DMI_SYS_VENDOR, "TUXEDO"),
570 		DMI_MATCH(DMI_BOARD_NAME, "POLARIS1501A2060"),
571 		},
572 	},
573 	{
574 	.callback = video_detect_force_native,
575 	.ident = "TongFang GKxNRxx",
576 	.matches = {
577 		DMI_MATCH(DMI_SYS_VENDOR, "TUXEDO"),
578 		DMI_MATCH(DMI_BOARD_NAME, "POLARIS1701A1650TI"),
579 		},
580 	},
581 	{
582 	.callback = video_detect_force_native,
583 	.ident = "TongFang GKxNRxx",
584 	.matches = {
585 		DMI_MATCH(DMI_SYS_VENDOR, "TUXEDO"),
586 		DMI_MATCH(DMI_BOARD_NAME, "POLARIS1701A2060"),
587 		},
588 	},
589 	{
590 	.callback = video_detect_force_native,
591 	.ident = "TongFang GMxNGxx",
592 	.matches = {
593 		DMI_MATCH(DMI_BOARD_NAME, "GMxNGxx"),
594 		},
595 	},
596 	{
597 	.callback = video_detect_force_native,
598 	.ident = "TongFang GMxZGxx",
599 	.matches = {
600 		DMI_MATCH(DMI_BOARD_NAME, "GMxZGxx"),
601 		},
602 	},
603 	{
604 	.callback = video_detect_force_native,
605 	.ident = "TongFang GMxRGxx",
606 	.matches = {
607 		DMI_MATCH(DMI_BOARD_NAME, "GMxRGxx"),
608 		},
609 	},
610 	/*
611 	 * Desktops which falsely report a backlight and which our heuristics
612 	 * for this do not catch.
613 	 */
614 	{
615 	 .callback = video_detect_force_none,
616 	 .ident = "Dell OptiPlex 9020M",
617 	 .matches = {
618 		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
619 		DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 9020M"),
620 		},
621 	},
622 	{
623 	 .callback = video_detect_force_none,
624 	 .ident = "MSI MS-7721",
625 	 .matches = {
626 		DMI_MATCH(DMI_SYS_VENDOR, "MSI"),
627 		DMI_MATCH(DMI_PRODUCT_NAME, "MS-7721"),
628 		},
629 	},
630 	{ },
631 };
632 
633 /* This uses a workqueue to avoid various locking ordering issues */
acpi_video_backlight_notify_work(struct work_struct * work)634 static void acpi_video_backlight_notify_work(struct work_struct *work)
635 {
636 	if (acpi_video_get_backlight_type() != acpi_backlight_video)
637 		acpi_video_unregister_backlight();
638 }
639 
acpi_video_backlight_notify(struct notifier_block * nb,unsigned long val,void * bd)640 static int acpi_video_backlight_notify(struct notifier_block *nb,
641 				       unsigned long val, void *bd)
642 {
643 	struct backlight_device *backlight = bd;
644 
645 	/* A raw bl registering may change video -> native */
646 	if (backlight->props.type == BACKLIGHT_RAW &&
647 	    val == BACKLIGHT_REGISTERED)
648 		schedule_work(&backlight_notify_work);
649 
650 	return NOTIFY_OK;
651 }
652 
653 /*
654  * Determine which type of backlight interface to use on this system,
655  * First check cmdline, then dmi quirks, then do autodetect.
656  *
657  * The autodetect order is:
658  * 1) Is the acpi-video backlight interface supported ->
659  *  no, use a vendor interface
660  * 2) Is this a win8 "ready" BIOS and do we have a native interface ->
661  *  yes, use a native interface
662  * 3) Else use the acpi-video interface
663  *
664  * Arguably the native on win8 check should be done first, but that would
665  * be a behavior change, which may causes issues.
666  */
acpi_video_get_backlight_type(void)667 enum acpi_backlight_type acpi_video_get_backlight_type(void)
668 {
669 	static DEFINE_MUTEX(init_mutex);
670 	static bool init_done;
671 	static long video_caps;
672 
673 	/* Parse cmdline, dmi and acpi only once */
674 	mutex_lock(&init_mutex);
675 	if (!init_done) {
676 		acpi_video_parse_cmdline();
677 		dmi_check_system(video_detect_dmi_table);
678 		acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
679 				    ACPI_UINT32_MAX, find_video, NULL,
680 				    &video_caps, NULL);
681 		INIT_WORK(&backlight_notify_work,
682 			  acpi_video_backlight_notify_work);
683 		backlight_nb.notifier_call = acpi_video_backlight_notify;
684 		backlight_nb.priority = 0;
685 		if (backlight_register_notifier(&backlight_nb) == 0)
686 			backlight_notifier_registered = true;
687 		init_done = true;
688 	}
689 	mutex_unlock(&init_mutex);
690 
691 	if (acpi_backlight_cmdline != acpi_backlight_undef)
692 		return acpi_backlight_cmdline;
693 
694 	if (acpi_backlight_dmi != acpi_backlight_undef)
695 		return acpi_backlight_dmi;
696 
697 	if (!(video_caps & ACPI_VIDEO_BACKLIGHT))
698 		return acpi_backlight_vendor;
699 
700 	if (acpi_osi_is_win8() && backlight_device_get_by_type(BACKLIGHT_RAW))
701 		return acpi_backlight_native;
702 
703 	return acpi_backlight_video;
704 }
705 EXPORT_SYMBOL(acpi_video_get_backlight_type);
706 
707 /*
708  * Set the preferred backlight interface type based on DMI info.
709  * This function allows DMI blacklists to be implemented by external
710  * platform drivers instead of putting a big blacklist in video_detect.c
711  */
acpi_video_set_dmi_backlight_type(enum acpi_backlight_type type)712 void acpi_video_set_dmi_backlight_type(enum acpi_backlight_type type)
713 {
714 	acpi_backlight_dmi = type;
715 	/* Remove acpi-video backlight interface if it is no longer desired */
716 	if (acpi_video_get_backlight_type() != acpi_backlight_video)
717 		acpi_video_unregister_backlight();
718 }
719 EXPORT_SYMBOL(acpi_video_set_dmi_backlight_type);
720 
acpi_video_detect_exit(void)721 void __exit acpi_video_detect_exit(void)
722 {
723 	if (backlight_notifier_registered)
724 		backlight_unregister_notifier(&backlight_nb);
725 }
726