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 = "Sony VPCEH3U1E",
144 	.matches = {
145 		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
146 		DMI_MATCH(DMI_PRODUCT_NAME, "VPCEH3U1E"),
147 		},
148 	},
149 
150 	/*
151 	 * These models have a working acpi_video backlight control, and using
152 	 * native backlight causes a regression where backlight does not work
153 	 * when userspace is not handling brightness key events. Disable
154 	 * native_backlight on these to fix this:
155 	 * https://bugzilla.kernel.org/show_bug.cgi?id=81691
156 	 */
157 	{
158 	 .callback = video_detect_force_video,
159 	 .ident = "ThinkPad T420",
160 	 .matches = {
161 		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
162 		DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T420"),
163 		},
164 	},
165 	{
166 	 .callback = video_detect_force_video,
167 	 .ident = "ThinkPad T520",
168 	 .matches = {
169 		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
170 		DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T520"),
171 		},
172 	},
173 	{
174 	 .callback = video_detect_force_video,
175 	 .ident = "ThinkPad X201s",
176 	 .matches = {
177 		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
178 		DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X201s"),
179 		},
180 	},
181 	{
182 	 .callback = video_detect_force_video,
183 	 .ident = "ThinkPad X201T",
184 	 .matches = {
185 		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
186 		DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X201T"),
187 		},
188 	},
189 
190 	/* The native backlight controls do not work on some older machines */
191 	{
192 	 /* https://bugs.freedesktop.org/show_bug.cgi?id=81515 */
193 	 .callback = video_detect_force_video,
194 	 .ident = "HP ENVY 15 Notebook",
195 	 .matches = {
196 		DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
197 		DMI_MATCH(DMI_PRODUCT_NAME, "HP ENVY 15 Notebook PC"),
198 		},
199 	},
200 	{
201 	 .callback = video_detect_force_video,
202 	 .ident = "SAMSUNG 870Z5E/880Z5E/680Z5E",
203 	 .matches = {
204 		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
205 		DMI_MATCH(DMI_PRODUCT_NAME, "870Z5E/880Z5E/680Z5E"),
206 		},
207 	},
208 	{
209 	 .callback = video_detect_force_video,
210 	 .ident = "SAMSUNG 370R4E/370R4V/370R5E/3570RE/370R5V",
211 	 .matches = {
212 		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
213 		DMI_MATCH(DMI_PRODUCT_NAME,
214 			  "370R4E/370R4V/370R5E/3570RE/370R5V"),
215 		},
216 	},
217 	{
218 	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1186097 */
219 	 .callback = video_detect_force_video,
220 	 .ident = "SAMSUNG 3570R/370R/470R/450R/510R/4450RV",
221 	 .matches = {
222 		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
223 		DMI_MATCH(DMI_PRODUCT_NAME,
224 			  "3570R/370R/470R/450R/510R/4450RV"),
225 		},
226 	},
227 	{
228 	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1557060 */
229 	 .callback = video_detect_force_video,
230 	 .ident = "SAMSUNG 670Z5E",
231 	 .matches = {
232 		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
233 		DMI_MATCH(DMI_PRODUCT_NAME, "670Z5E"),
234 		},
235 	},
236 	{
237 	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1094948 */
238 	 .callback = video_detect_force_video,
239 	 .ident = "SAMSUNG 730U3E/740U3E",
240 	 .matches = {
241 		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
242 		DMI_MATCH(DMI_PRODUCT_NAME, "730U3E/740U3E"),
243 		},
244 	},
245 	{
246 	 /* https://bugs.freedesktop.org/show_bug.cgi?id=87286 */
247 	 .callback = video_detect_force_video,
248 	 .ident = "SAMSUNG 900X3C/900X3D/900X3E/900X4C/900X4D",
249 	 .matches = {
250 		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
251 		DMI_MATCH(DMI_PRODUCT_NAME,
252 			  "900X3C/900X3D/900X3E/900X4C/900X4D"),
253 		},
254 	},
255 	{
256 	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1272633 */
257 	 .callback = video_detect_force_video,
258 	 .ident = "Dell XPS14 L421X",
259 	 .matches = {
260 		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
261 		DMI_MATCH(DMI_PRODUCT_NAME, "XPS L421X"),
262 		},
263 	},
264 	{
265 	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1163574 */
266 	 .callback = video_detect_force_video,
267 	 .ident = "Dell XPS15 L521X",
268 	 .matches = {
269 		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
270 		DMI_MATCH(DMI_PRODUCT_NAME, "XPS L521X"),
271 		},
272 	},
273 	{
274 	 /* https://bugzilla.kernel.org/show_bug.cgi?id=108971 */
275 	 .callback = video_detect_force_video,
276 	 .ident = "SAMSUNG 530U4E/540U4E",
277 	 .matches = {
278 		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
279 		DMI_MATCH(DMI_PRODUCT_NAME, "530U4E/540U4E"),
280 		},
281 	},
282 	/* https://bugs.launchpad.net/bugs/1894667 */
283 	{
284 	 .callback = video_detect_force_video,
285 	 .ident = "HP 635 Notebook",
286 	 .matches = {
287 		DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
288 		DMI_MATCH(DMI_PRODUCT_NAME, "HP 635 Notebook PC"),
289 		},
290 	},
291 
292 	/* Non win8 machines which need native backlight nevertheless */
293 	{
294 	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1201530 */
295 	 .callback = video_detect_force_native,
296 	 .ident = "Lenovo Ideapad S405",
297 	 .matches = {
298 		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
299 		DMI_MATCH(DMI_BOARD_NAME, "Lenovo IdeaPad S405"),
300 		},
301 	},
302 	{
303 	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1187004 */
304 	 .callback = video_detect_force_native,
305 	 .ident = "Lenovo Ideapad Z570",
306 	 .matches = {
307 		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
308 		DMI_MATCH(DMI_PRODUCT_NAME, "102434U"),
309 		},
310 	},
311 	{
312 	 .callback = video_detect_force_native,
313 	 .ident = "Lenovo E41-25",
314 	 .matches = {
315 		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
316 		DMI_MATCH(DMI_PRODUCT_NAME, "81FS"),
317 		},
318 	},
319 	{
320 	 .callback = video_detect_force_native,
321 	 .ident = "Lenovo E41-45",
322 	 .matches = {
323 		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
324 		DMI_MATCH(DMI_PRODUCT_NAME, "82BK"),
325 		},
326 	},
327 	{
328 	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1217249 */
329 	 .callback = video_detect_force_native,
330 	 .ident = "Apple MacBook Pro 12,1",
331 	 .matches = {
332 		DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
333 		DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro12,1"),
334 		},
335 	},
336 	{
337 	 .callback = video_detect_force_native,
338 	 .ident = "Dell Vostro V131",
339 	 .matches = {
340 		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
341 		DMI_MATCH(DMI_PRODUCT_NAME, "Vostro V131"),
342 		},
343 	},
344 	{
345 	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1123661 */
346 	 .callback = video_detect_force_native,
347 	 .ident = "Dell XPS 17 L702X",
348 	 .matches = {
349 		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
350 		DMI_MATCH(DMI_PRODUCT_NAME, "Dell System XPS L702X"),
351 		},
352 	},
353 	{
354 	 .callback = video_detect_force_native,
355 	 .ident = "Dell Precision 7510",
356 	 .matches = {
357 		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
358 		DMI_MATCH(DMI_PRODUCT_NAME, "Precision 7510"),
359 		},
360 	},
361 	{
362 	 .callback = video_detect_force_native,
363 	 .ident = "Acer Aspire 5738z",
364 	 .matches = {
365 		DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
366 		DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5738"),
367 		DMI_MATCH(DMI_BOARD_NAME, "JV50"),
368 		},
369 	},
370 	{
371 	 /* https://bugzilla.kernel.org/show_bug.cgi?id=207835 */
372 	 .callback = video_detect_force_native,
373 	 .ident = "Acer TravelMate 5735Z",
374 	 .matches = {
375 		DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
376 		DMI_MATCH(DMI_PRODUCT_NAME, "TravelMate 5735Z"),
377 		DMI_MATCH(DMI_BOARD_NAME, "BA51_MV"),
378 		},
379 	},
380 
381 	/*
382 	 * Desktops which falsely report a backlight and which our heuristics
383 	 * for this do not catch.
384 	 */
385 	{
386 	 .callback = video_detect_force_none,
387 	 .ident = "Dell OptiPlex 9020M",
388 	 .matches = {
389 		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
390 		DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 9020M"),
391 		},
392 	},
393 	{
394 	 .callback = video_detect_force_none,
395 	 .ident = "MSI MS-7721",
396 	 .matches = {
397 		DMI_MATCH(DMI_SYS_VENDOR, "MSI"),
398 		DMI_MATCH(DMI_PRODUCT_NAME, "MS-7721"),
399 		},
400 	},
401 	{ },
402 };
403 
404 /* This uses a workqueue to avoid various locking ordering issues */
acpi_video_backlight_notify_work(struct work_struct * work)405 static void acpi_video_backlight_notify_work(struct work_struct *work)
406 {
407 	if (acpi_video_get_backlight_type() != acpi_backlight_video)
408 		acpi_video_unregister_backlight();
409 }
410 
acpi_video_backlight_notify(struct notifier_block * nb,unsigned long val,void * bd)411 static int acpi_video_backlight_notify(struct notifier_block *nb,
412 				       unsigned long val, void *bd)
413 {
414 	struct backlight_device *backlight = bd;
415 
416 	/* A raw bl registering may change video -> native */
417 	if (backlight->props.type == BACKLIGHT_RAW &&
418 	    val == BACKLIGHT_REGISTERED)
419 		schedule_work(&backlight_notify_work);
420 
421 	return NOTIFY_OK;
422 }
423 
424 /*
425  * Determine which type of backlight interface to use on this system,
426  * First check cmdline, then dmi quirks, then do autodetect.
427  *
428  * The autodetect order is:
429  * 1) Is the acpi-video backlight interface supported ->
430  *  no, use a vendor interface
431  * 2) Is this a win8 "ready" BIOS and do we have a native interface ->
432  *  yes, use a native interface
433  * 3) Else use the acpi-video interface
434  *
435  * Arguably the native on win8 check should be done first, but that would
436  * be a behavior change, which may causes issues.
437  */
acpi_video_get_backlight_type(void)438 enum acpi_backlight_type acpi_video_get_backlight_type(void)
439 {
440 	static DEFINE_MUTEX(init_mutex);
441 	static bool init_done;
442 	static long video_caps;
443 
444 	/* Parse cmdline, dmi and acpi only once */
445 	mutex_lock(&init_mutex);
446 	if (!init_done) {
447 		acpi_video_parse_cmdline();
448 		dmi_check_system(video_detect_dmi_table);
449 		acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
450 				    ACPI_UINT32_MAX, find_video, NULL,
451 				    &video_caps, NULL);
452 		INIT_WORK(&backlight_notify_work,
453 			  acpi_video_backlight_notify_work);
454 		backlight_nb.notifier_call = acpi_video_backlight_notify;
455 		backlight_nb.priority = 0;
456 		if (backlight_register_notifier(&backlight_nb) == 0)
457 			backlight_notifier_registered = true;
458 		init_done = true;
459 	}
460 	mutex_unlock(&init_mutex);
461 
462 	if (acpi_backlight_cmdline != acpi_backlight_undef)
463 		return acpi_backlight_cmdline;
464 
465 	if (acpi_backlight_dmi != acpi_backlight_undef)
466 		return acpi_backlight_dmi;
467 
468 	if (!(video_caps & ACPI_VIDEO_BACKLIGHT))
469 		return acpi_backlight_vendor;
470 
471 	if (acpi_osi_is_win8() && backlight_device_get_by_type(BACKLIGHT_RAW))
472 		return acpi_backlight_native;
473 
474 	return acpi_backlight_video;
475 }
476 EXPORT_SYMBOL(acpi_video_get_backlight_type);
477 
478 /*
479  * Set the preferred backlight interface type based on DMI info.
480  * This function allows DMI blacklists to be implemented by external
481  * platform drivers instead of putting a big blacklist in video_detect.c
482  */
acpi_video_set_dmi_backlight_type(enum acpi_backlight_type type)483 void acpi_video_set_dmi_backlight_type(enum acpi_backlight_type type)
484 {
485 	acpi_backlight_dmi = type;
486 	/* Remove acpi-video backlight interface if it is no longer desired */
487 	if (acpi_video_get_backlight_type() != acpi_backlight_video)
488 		acpi_video_unregister_backlight();
489 }
490 EXPORT_SYMBOL(acpi_video_set_dmi_backlight_type);
491 
acpi_video_detect_exit(void)492 void __exit acpi_video_detect_exit(void)
493 {
494 	if (backlight_notifier_registered)
495 		backlight_unregister_notifier(&backlight_nb);
496 }
497