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v5.9
  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
 38ACPI_MODULE_NAME("video");
 39#define _COMPONENT		ACPI_VIDEO_COMPONENT
 40
 41void acpi_video_unregister_backlight(void);
 42
 43static bool backlight_notifier_registered;
 44static struct notifier_block backlight_nb;
 45static struct work_struct backlight_notify_work;
 46
 47static enum acpi_backlight_type acpi_backlight_cmdline = acpi_backlight_undef;
 48static enum acpi_backlight_type acpi_backlight_dmi = acpi_backlight_undef;
 49
 50static void acpi_video_parse_cmdline(void)
 51{
 52	if (!strcmp("vendor", acpi_video_backlight_string))
 53		acpi_backlight_cmdline = acpi_backlight_vendor;
 54	if (!strcmp("video", acpi_video_backlight_string))
 55		acpi_backlight_cmdline = acpi_backlight_video;
 56	if (!strcmp("native", acpi_video_backlight_string))
 57		acpi_backlight_cmdline = acpi_backlight_native;
 
 
 
 
 58	if (!strcmp("none", acpi_video_backlight_string))
 59		acpi_backlight_cmdline = acpi_backlight_none;
 60}
 61
 62static acpi_status
 63find_video(acpi_handle handle, u32 lvl, void *context, void **rv)
 64{
 
 65	long *cap = context;
 66	struct pci_dev *dev;
 67	struct acpi_device *acpi_dev;
 68
 69	static const struct acpi_device_id video_ids[] = {
 70		{ACPI_VIDEO_HID, 0},
 71		{"", 0},
 72	};
 73	if (acpi_bus_get_device(handle, &acpi_dev))
 74		return AE_OK;
 75
 76	if (!acpi_match_device_ids(acpi_dev, video_ids)) {
 77		dev = acpi_get_pci_dev(handle);
 78		if (!dev)
 79			return AE_OK;
 80		pci_dev_put(dev);
 81		*cap |= acpi_is_video_device(handle);
 82	}
 83	return AE_OK;
 84}
 85
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 86/* Force to use vendor driver when the ACPI device is known to be
 87 * buggy */
 88static int video_detect_force_vendor(const struct dmi_system_id *d)
 89{
 90	acpi_backlight_dmi = acpi_backlight_vendor;
 91	return 0;
 92}
 93
 94static int video_detect_force_video(const struct dmi_system_id *d)
 95{
 96	acpi_backlight_dmi = acpi_backlight_video;
 97	return 0;
 98}
 99
100static int video_detect_force_native(const struct dmi_system_id *d)
101{
102	acpi_backlight_dmi = acpi_backlight_native;
103	return 0;
104}
105
106static int video_detect_force_none(const struct dmi_system_id *d)
107{
108	acpi_backlight_dmi = acpi_backlight_none;
109	return 0;
110}
111
112static const struct dmi_system_id video_detect_dmi_table[] = {
113	/* On Samsung X360, the BIOS will set a flag (VDRV) if generic
114	 * ACPI backlight device is used. This flag will definitively break
115	 * the backlight interface (even the vendor interface) until next
116	 * reboot. It's why we should prevent video.ko from being used here
117	 * and we can't rely on a later call to acpi_video_unregister().
118	 */
119	{
 
120	 .callback = video_detect_force_vendor,
121	 .ident = "X360",
122	 .matches = {
123		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
124		DMI_MATCH(DMI_PRODUCT_NAME, "X360"),
125		DMI_MATCH(DMI_BOARD_NAME, "X360"),
126		},
127	},
128	{
129	.callback = video_detect_force_vendor,
130	.ident = "Asus UL30VT",
131	.matches = {
132		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
133		DMI_MATCH(DMI_PRODUCT_NAME, "UL30VT"),
134		},
135	},
136	{
137	.callback = video_detect_force_vendor,
138	.ident = "Asus UL30A",
139	.matches = {
140		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
141		DMI_MATCH(DMI_PRODUCT_NAME, "UL30A"),
142		},
143	},
144	{
145	.callback = video_detect_force_vendor,
146	.ident = "Sony VPCEH3U1E",
147	.matches = {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
148		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
149		DMI_MATCH(DMI_PRODUCT_NAME, "VPCEH3U1E"),
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
150		},
151	},
152
153	/*
154	 * These models have a working acpi_video backlight control, and using
155	 * native backlight causes a regression where backlight does not work
156	 * when userspace is not handling brightness key events. Disable
157	 * native_backlight on these to fix this:
158	 * https://bugzilla.kernel.org/show_bug.cgi?id=81691
159	 */
160	{
161	 .callback = video_detect_force_video,
162	 .ident = "ThinkPad T420",
163	 .matches = {
164		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
165		DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T420"),
166		},
167	},
168	{
169	 .callback = video_detect_force_video,
170	 .ident = "ThinkPad T520",
171	 .matches = {
172		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
173		DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T520"),
174		},
175	},
176	{
177	 .callback = video_detect_force_video,
178	 .ident = "ThinkPad X201s",
179	 .matches = {
180		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
181		DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X201s"),
182		},
183	},
184        {
185         .callback = video_detect_force_video,
186         .ident = "ThinkPad X201T",
187         .matches = {
188                DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
189                DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X201T"),
190                },
191        },
192
193	/* The native backlight controls do not work on some older machines */
194	{
195	 /* https://bugs.freedesktop.org/show_bug.cgi?id=81515 */
196	 .callback = video_detect_force_video,
197	 .ident = "HP ENVY 15 Notebook",
198	 .matches = {
199		DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
200		DMI_MATCH(DMI_PRODUCT_NAME, "HP ENVY 15 Notebook PC"),
201		},
202	},
203	{
204	 .callback = video_detect_force_video,
205	 .ident = "SAMSUNG 870Z5E/880Z5E/680Z5E",
206	 .matches = {
207		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
208		DMI_MATCH(DMI_PRODUCT_NAME, "870Z5E/880Z5E/680Z5E"),
209		},
210	},
211	{
212	 .callback = video_detect_force_video,
213	 .ident = "SAMSUNG 370R4E/370R4V/370R5E/3570RE/370R5V",
214	 .matches = {
215		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
216		DMI_MATCH(DMI_PRODUCT_NAME,
217			  "370R4E/370R4V/370R5E/3570RE/370R5V"),
218		},
219	},
220	{
221	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1186097 */
222	 .callback = video_detect_force_video,
223	 .ident = "SAMSUNG 3570R/370R/470R/450R/510R/4450RV",
224	 .matches = {
225		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
226		DMI_MATCH(DMI_PRODUCT_NAME,
227			  "3570R/370R/470R/450R/510R/4450RV"),
228		},
229	},
230	{
231	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1557060 */
232	 .callback = video_detect_force_video,
233	 .ident = "SAMSUNG 670Z5E",
234	 .matches = {
235		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
236		DMI_MATCH(DMI_PRODUCT_NAME, "670Z5E"),
237		},
238	},
239	{
240	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1094948 */
241	 .callback = video_detect_force_video,
242	 .ident = "SAMSUNG 730U3E/740U3E",
243	 .matches = {
244		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
245		DMI_MATCH(DMI_PRODUCT_NAME, "730U3E/740U3E"),
246		},
247	},
248	{
249	 /* https://bugs.freedesktop.org/show_bug.cgi?id=87286 */
250	 .callback = video_detect_force_video,
251	 .ident = "SAMSUNG 900X3C/900X3D/900X3E/900X4C/900X4D",
252	 .matches = {
253		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
254		DMI_MATCH(DMI_PRODUCT_NAME,
255			  "900X3C/900X3D/900X3E/900X4C/900X4D"),
256		},
257	},
258	{
259	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1272633 */
260	 .callback = video_detect_force_video,
261	 .ident = "Dell XPS14 L421X",
262	 .matches = {
263		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
264		DMI_MATCH(DMI_PRODUCT_NAME, "XPS L421X"),
265		},
266	},
267	{
268	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1163574 */
269	 .callback = video_detect_force_video,
270	 .ident = "Dell XPS15 L521X",
271	 .matches = {
272		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
273		DMI_MATCH(DMI_PRODUCT_NAME, "XPS L521X"),
274		},
275	},
276	{
277	 /* https://bugzilla.kernel.org/show_bug.cgi?id=108971 */
278	 .callback = video_detect_force_video,
279	 .ident = "SAMSUNG 530U4E/540U4E",
280	 .matches = {
281		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
282		DMI_MATCH(DMI_PRODUCT_NAME, "530U4E/540U4E"),
283		},
284	},
 
 
 
 
 
 
 
 
 
285
286	/* Non win8 machines which need native backlight nevertheless */
287	{
288	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1201530 */
289	 .callback = video_detect_force_native,
290	 .ident = "Lenovo Ideapad S405",
291	 .matches = {
292		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
293		DMI_MATCH(DMI_BOARD_NAME, "Lenovo IdeaPad S405"),
294		},
295	},
296	{
297	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1187004 */
298	 .callback = video_detect_force_native,
299	 .ident = "Lenovo Ideapad Z570",
300	 .matches = {
301		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
302		DMI_MATCH(DMI_PRODUCT_NAME, "102434U"),
303		},
304	},
305	{
306	 .callback = video_detect_force_native,
307	 .ident = "Lenovo E41-25",
308	 .matches = {
309		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
310		DMI_MATCH(DMI_PRODUCT_NAME, "81FS"),
311		},
312	},
313	{
314	 .callback = video_detect_force_native,
315	 .ident = "Lenovo E41-45",
316	 .matches = {
317		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
318		DMI_MATCH(DMI_PRODUCT_NAME, "82BK"),
319		},
320	},
321	{
322	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1217249 */
323	 .callback = video_detect_force_native,
324	 .ident = "Apple MacBook Pro 12,1",
325	 .matches = {
326		DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
327		DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro12,1"),
328		},
329	},
330	{
331	 .callback = video_detect_force_native,
332	 .ident = "Dell Vostro V131",
 
 
 
 
 
 
 
 
333	 .matches = {
334		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
335		DMI_MATCH(DMI_PRODUCT_NAME, "Vostro V131"),
336		},
337	},
338	{
339	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1123661 */
340	 .callback = video_detect_force_native,
341	 .ident = "Dell XPS 17 L702X",
342	 .matches = {
343		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
344		DMI_MATCH(DMI_PRODUCT_NAME, "Dell System XPS L702X"),
345		},
346	},
347	{
348	 .callback = video_detect_force_native,
349	 .ident = "Dell Precision 7510",
350	 .matches = {
351		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
352		DMI_MATCH(DMI_PRODUCT_NAME, "Precision 7510"),
353		},
354	},
355	{
356	 .callback = video_detect_force_native,
357	 .ident = "Acer Aspire 5738z",
 
 
 
 
 
 
 
 
358	 .matches = {
359		DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
360		DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5738"),
361		DMI_MATCH(DMI_BOARD_NAME, "JV50"),
362		},
363	},
364	{
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
365	 /* https://bugzilla.kernel.org/show_bug.cgi?id=207835 */
366	 .callback = video_detect_force_native,
367	 .ident = "Acer TravelMate 5735Z",
368	 .matches = {
369		DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
370		DMI_MATCH(DMI_PRODUCT_NAME, "TravelMate 5735Z"),
371		DMI_MATCH(DMI_BOARD_NAME, "BA51_MV"),
372		},
373	},
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
374
375	/*
376	 * Desktops which falsely report a backlight and which our heuristics
377	 * for this do not catch.
378	 */
379	{
380	 .callback = video_detect_force_none,
381	 .ident = "Dell OptiPlex 9020M",
382	 .matches = {
383		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
384		DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 9020M"),
385		},
386	},
387	{
388	 .callback = video_detect_force_none,
389	 .ident = "MSI MS-7721",
 
 
 
 
 
 
 
 
390	 .matches = {
391		DMI_MATCH(DMI_SYS_VENDOR, "MSI"),
392		DMI_MATCH(DMI_PRODUCT_NAME, "MS-7721"),
393		},
394	},
395	{ },
396};
397
398/* This uses a workqueue to avoid various locking ordering issues */
399static void acpi_video_backlight_notify_work(struct work_struct *work)
400{
401	if (acpi_video_get_backlight_type() != acpi_backlight_video)
402		acpi_video_unregister_backlight();
403}
404
405static int acpi_video_backlight_notify(struct notifier_block *nb,
406				       unsigned long val, void *bd)
 
 
 
 
407{
408	struct backlight_device *backlight = bd;
409
410	/* A raw bl registering may change video -> native */
411	if (backlight->props.type == BACKLIGHT_RAW &&
412	    val == BACKLIGHT_REGISTERED)
413		schedule_work(&backlight_notify_work);
414
415	return NOTIFY_OK;
416}
417
418/*
419 * Determine which type of backlight interface to use on this system,
420 * First check cmdline, then dmi quirks, then do autodetect.
421 *
422 * The autodetect order is:
423 * 1) Is the acpi-video backlight interface supported ->
424 *  no, use a vendor interface
425 * 2) Is this a win8 "ready" BIOS and do we have a native interface ->
426 *  yes, use a native interface
427 * 3) Else use the acpi-video interface
428 *
429 * Arguably the native on win8 check should be done first, but that would
430 * be a behavior change, which may causes issues.
431 */
432enum acpi_backlight_type acpi_video_get_backlight_type(void)
433{
434	static DEFINE_MUTEX(init_mutex);
 
 
 
435	static bool init_done;
436	static long video_caps;
437
438	/* Parse cmdline, dmi and acpi only once */
439	mutex_lock(&init_mutex);
440	if (!init_done) {
441		acpi_video_parse_cmdline();
442		dmi_check_system(video_detect_dmi_table);
443		acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
444				    ACPI_UINT32_MAX, find_video, NULL,
445				    &video_caps, NULL);
446		INIT_WORK(&backlight_notify_work,
447			  acpi_video_backlight_notify_work);
448		backlight_nb.notifier_call = acpi_video_backlight_notify;
449		backlight_nb.priority = 0;
450		if (backlight_register_notifier(&backlight_nb) == 0)
451			backlight_notifier_registered = true;
452		init_done = true;
453	}
 
 
454	mutex_unlock(&init_mutex);
455
 
 
 
 
456	if (acpi_backlight_cmdline != acpi_backlight_undef)
457		return acpi_backlight_cmdline;
458
 
459	if (acpi_backlight_dmi != acpi_backlight_undef)
460		return acpi_backlight_dmi;
461
462	if (!(video_caps & ACPI_VIDEO_BACKLIGHT))
463		return acpi_backlight_vendor;
 
 
 
 
 
 
 
 
 
464
465	if (acpi_osi_is_win8() && backlight_device_get_by_type(BACKLIGHT_RAW))
 
466		return acpi_backlight_native;
467
468	return acpi_backlight_video;
 
469}
470EXPORT_SYMBOL(acpi_video_get_backlight_type);
471
472/*
473 * Set the preferred backlight interface type based on DMI info.
474 * This function allows DMI blacklists to be implemented by external
475 * platform drivers instead of putting a big blacklist in video_detect.c
476 */
477void acpi_video_set_dmi_backlight_type(enum acpi_backlight_type type)
478{
479	acpi_backlight_dmi = type;
480	/* Remove acpi-video backlight interface if it is no longer desired */
481	if (acpi_video_get_backlight_type() != acpi_backlight_video)
482		acpi_video_unregister_backlight();
483}
484EXPORT_SYMBOL(acpi_video_set_dmi_backlight_type);
485
486void __exit acpi_video_detect_exit(void)
487{
488	if (backlight_notifier_registered)
489		backlight_unregister_notifier(&backlight_nb);
490}
v6.2
  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 which
 21 * driver should handle the backlight. RAW/GPU-driver backlight drivers must
 22 * use the acpi_video_backlight_use_native() helper for this.
 23 *
 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.
 27 */
 28
 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>
 41
 
 
 
 
 
 
 
 
 
 42static enum acpi_backlight_type acpi_backlight_cmdline = acpi_backlight_undef;
 43static enum acpi_backlight_type acpi_backlight_dmi = acpi_backlight_undef;
 44
 45static void acpi_video_parse_cmdline(void)
 46{
 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;
 59}
 60
 61static acpi_status
 62find_video(acpi_handle handle, u32 lvl, void *context, void **rv)
 63{
 64	struct acpi_device *acpi_dev = acpi_fetch_acpi_dev(handle);
 65	long *cap = context;
 66	struct pci_dev *dev;
 
 67
 68	static const struct acpi_device_id video_ids[] = {
 69		{ACPI_VIDEO_HID, 0},
 70		{"", 0},
 71	};
 
 
 72
 73	if (acpi_dev && !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/* This depends on ACPI_WMI which is X86 only */
 84#ifdef CONFIG_X86
 85static bool nvidia_wmi_ec_supported(void)
 86{
 87	struct wmi_brightness_args args = {
 88		.mode = WMI_BRIGHTNESS_MODE_GET,
 89		.val = 0,
 90		.ret = 0,
 91	};
 92	struct acpi_buffer buf = { (acpi_size)sizeof(args), &args };
 93	acpi_status status;
 94
 95	status = wmi_evaluate_method(WMI_BRIGHTNESS_GUID, 0,
 96				     WMI_BRIGHTNESS_METHOD_SOURCE, &buf, &buf);
 97	if (ACPI_FAILURE(status))
 98		return false;
 99
100	/*
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.
103	 */
104	return args.ret == WMI_BRIGHTNESS_SOURCE_EC;
105}
106#else
107static bool nvidia_wmi_ec_supported(void)
108{
109	return false;
110}
111#endif
112
113/* Force to use vendor driver when the ACPI device is known to be
114 * buggy */
115static int video_detect_force_vendor(const struct dmi_system_id *d)
116{
117	acpi_backlight_dmi = acpi_backlight_vendor;
118	return 0;
119}
120
121static int video_detect_force_video(const struct dmi_system_id *d)
122{
123	acpi_backlight_dmi = acpi_backlight_video;
124	return 0;
125}
126
127static int video_detect_force_native(const struct dmi_system_id *d)
128{
129	acpi_backlight_dmi = acpi_backlight_native;
130	return 0;
131}
132
133static int video_detect_force_none(const struct dmi_system_id *d)
134{
135	acpi_backlight_dmi = acpi_backlight_none;
136	return 0;
137}
138
139static const struct dmi_system_id video_detect_dmi_table[] = {
140	/*
141	 * Models which should use the vendor backlight interface,
142	 * because of broken ACPI video backlight control.
 
 
143	 */
144	{
145	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1128309 */
146	 .callback = video_detect_force_vendor,
147	 /* Acer KAV80 */
148	 .matches = {
149		DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
150		DMI_MATCH(DMI_PRODUCT_NAME, "KAV80"),
 
151		},
152	},
153	{
154	 .callback = video_detect_force_vendor,
155	 /* Asus UL30VT */
156	 .matches = {
157		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
158		DMI_MATCH(DMI_PRODUCT_NAME, "UL30VT"),
159		},
160	},
161	{
162	 .callback = video_detect_force_vendor,
163	 /* Asus UL30A */
164	 .matches = {
165		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
166		DMI_MATCH(DMI_PRODUCT_NAME, "UL30A"),
167		},
168	},
169	{
170	 .callback = video_detect_force_vendor,
171	 /* Asus X55U */
172	 .matches = {
173		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
174		DMI_MATCH(DMI_PRODUCT_NAME, "X55U"),
175		},
176	},
177	{
178	 /* https://bugs.launchpad.net/bugs/1000146 */
179	 .callback = video_detect_force_vendor,
180	 /* Asus X101CH */
181	 .matches = {
182		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
183		DMI_MATCH(DMI_PRODUCT_NAME, "X101CH"),
184		},
185	},
186	{
187	 .callback = video_detect_force_vendor,
188	 /* Asus X401U */
189	 .matches = {
190		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
191		DMI_MATCH(DMI_PRODUCT_NAME, "X401U"),
192		},
193	},
194	{
195	 .callback = video_detect_force_vendor,
196	 /* Asus X501U */
197	 .matches = {
198		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
199		DMI_MATCH(DMI_PRODUCT_NAME, "X501U"),
200		},
201	},
202	{
203	 /* https://bugs.launchpad.net/bugs/1000146 */
204	 .callback = video_detect_force_vendor,
205	 /* Asus 1015CX */
206	 .matches = {
207		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
208		DMI_MATCH(DMI_PRODUCT_NAME, "1015CX"),
209		},
210	},
211	{
212	 .callback = video_detect_force_vendor,
213	 /* Samsung N150/N210/N220 */
214	 .matches = {
215		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
216		DMI_MATCH(DMI_PRODUCT_NAME, "N150/N210/N220"),
217		DMI_MATCH(DMI_BOARD_NAME, "N150/N210/N220"),
218		},
219	},
220	{
221	 .callback = video_detect_force_vendor,
222	 /* Samsung NF110/NF210/NF310 */
223	 .matches = {
224		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
225		DMI_MATCH(DMI_PRODUCT_NAME, "NF110/NF210/NF310"),
226		DMI_MATCH(DMI_BOARD_NAME, "NF110/NF210/NF310"),
227		},
228	},
229	{
230	 .callback = video_detect_force_vendor,
231	 /* Samsung NC210 */
232	 .matches = {
233		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
234		DMI_MATCH(DMI_PRODUCT_NAME, "NC210/NC110"),
235		DMI_MATCH(DMI_BOARD_NAME, "NC210/NC110"),
236		},
237	},
238	{
239	 .callback = video_detect_force_vendor,
240	 /* Xiaomi Mi Pad 2 */
241	 .matches = {
242			DMI_MATCH(DMI_SYS_VENDOR, "Xiaomi Inc"),
243			DMI_MATCH(DMI_PRODUCT_NAME, "Mipad2"),
244		},
245	},
246
247	/*
248	 * Models which should use the vendor backlight interface,
249	 * because of broken native backlight control.
250	 */
251	{
252	 .callback = video_detect_force_vendor,
253	 /* Sony Vaio PCG-FRV35 */
254	 .matches = {
255		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
256		DMI_MATCH(DMI_PRODUCT_NAME, "PCG-FRV35"),
257		},
258	},
259
260	/*
261	 * Toshiba models with Transflective display, these need to use
262	 * the toshiba_acpi vendor driver for proper Transflective handling.
263	 */
264	{
265	 .callback = video_detect_force_vendor,
266	 .matches = {
267		DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
268		DMI_MATCH(DMI_PRODUCT_NAME, "PORTEGE R500"),
269		},
270	},
271	{
272	 .callback = video_detect_force_vendor,
273	 .matches = {
274		DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
275		DMI_MATCH(DMI_PRODUCT_NAME, "PORTEGE R600"),
276		},
277	},
278
279	/*
280	 * These models have a working acpi_video backlight control, and using
281	 * native backlight causes a regression where backlight does not work
282	 * when userspace is not handling brightness key events. Disable
283	 * native_backlight on these to fix this:
284	 * https://bugzilla.kernel.org/show_bug.cgi?id=81691
285	 */
286	{
287	 .callback = video_detect_force_video,
288	 /* ThinkPad T420 */
289	 .matches = {
290		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
291		DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T420"),
292		},
293	},
294	{
295	 .callback = video_detect_force_video,
296	 /* ThinkPad T520 */
297	 .matches = {
298		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
299		DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T520"),
300		},
301	},
302	{
303	 .callback = video_detect_force_video,
304	 /* ThinkPad X201s */
305	 .matches = {
306		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
307		DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X201s"),
308		},
309	},
310	{
311	 .callback = video_detect_force_video,
312	 /* ThinkPad X201T */
313	 .matches = {
314		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
315		DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X201T"),
316		},
317	},
318
319	/* The native backlight controls do not work on some older machines */
320	{
321	 /* https://bugs.freedesktop.org/show_bug.cgi?id=81515 */
322	 .callback = video_detect_force_video,
323	 /* HP ENVY 15 Notebook */
324	 .matches = {
325		DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
326		DMI_MATCH(DMI_PRODUCT_NAME, "HP ENVY 15 Notebook PC"),
327		},
328	},
329	{
330	 .callback = video_detect_force_video,
331	 /* SAMSUNG 870Z5E/880Z5E/680Z5E */
332	 .matches = {
333		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
334		DMI_MATCH(DMI_PRODUCT_NAME, "870Z5E/880Z5E/680Z5E"),
335		},
336	},
337	{
338	 .callback = video_detect_force_video,
339	 /* SAMSUNG 370R4E/370R4V/370R5E/3570RE/370R5V */
340	 .matches = {
341		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
342		DMI_MATCH(DMI_PRODUCT_NAME,
343			  "370R4E/370R4V/370R5E/3570RE/370R5V"),
344		},
345	},
346	{
347	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1186097 */
348	 .callback = video_detect_force_video,
349	 /* SAMSUNG 3570R/370R/470R/450R/510R/4450RV */
350	 .matches = {
351		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
352		DMI_MATCH(DMI_PRODUCT_NAME,
353			  "3570R/370R/470R/450R/510R/4450RV"),
354		},
355	},
356	{
357	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1557060 */
358	 .callback = video_detect_force_video,
359	 /* SAMSUNG 670Z5E */
360	 .matches = {
361		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
362		DMI_MATCH(DMI_PRODUCT_NAME, "670Z5E"),
363		},
364	},
365	{
366	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1094948 */
367	 .callback = video_detect_force_video,
368	 /* SAMSUNG 730U3E/740U3E */
369	 .matches = {
370		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
371		DMI_MATCH(DMI_PRODUCT_NAME, "730U3E/740U3E"),
372		},
373	},
374	{
375	 /* https://bugs.freedesktop.org/show_bug.cgi?id=87286 */
376	 .callback = video_detect_force_video,
377	 /* SAMSUNG 900X3C/900X3D/900X3E/900X4C/900X4D */
378	 .matches = {
379		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
380		DMI_MATCH(DMI_PRODUCT_NAME,
381			  "900X3C/900X3D/900X3E/900X4C/900X4D"),
382		},
383	},
384	{
385	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1272633 */
386	 .callback = video_detect_force_video,
387	 /* Dell XPS14 L421X */
388	 .matches = {
389		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
390		DMI_MATCH(DMI_PRODUCT_NAME, "XPS L421X"),
391		},
392	},
393	{
394	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1163574 */
395	 .callback = video_detect_force_video,
396	 /* Dell XPS15 L521X */
397	 .matches = {
398		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
399		DMI_MATCH(DMI_PRODUCT_NAME, "XPS L521X"),
400		},
401	},
402	{
403	 /* https://bugzilla.kernel.org/show_bug.cgi?id=108971 */
404	 .callback = video_detect_force_video,
405	 /* SAMSUNG 530U4E/540U4E */
406	 .matches = {
407		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
408		DMI_MATCH(DMI_PRODUCT_NAME, "530U4E/540U4E"),
409		},
410	},
411	{
412	 /* https://bugs.launchpad.net/bugs/1894667 */
413	 .callback = video_detect_force_video,
414	 /* HP 635 Notebook */
415	 .matches = {
416		DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
417		DMI_MATCH(DMI_PRODUCT_NAME, "HP 635 Notebook PC"),
418		},
419	},
420
421	/* Non win8 machines which need native backlight nevertheless */
422	{
423	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1201530 */
424	 .callback = video_detect_force_native,
425	 /* Lenovo Ideapad S405 */
426	 .matches = {
427		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
428		DMI_MATCH(DMI_BOARD_NAME, "Lenovo IdeaPad S405"),
429		},
430	},
431	{
432	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1187004 */
433	 .callback = video_detect_force_native,
434	 /* Lenovo Ideapad Z570 */
435	 .matches = {
436		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
437		DMI_MATCH(DMI_PRODUCT_NAME, "102434U"),
438		},
439	},
440	{
441	 .callback = video_detect_force_native,
442	 /* Lenovo E41-25 */
443	 .matches = {
444		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
445		DMI_MATCH(DMI_PRODUCT_NAME, "81FS"),
446		},
447	},
448	{
449	 .callback = video_detect_force_native,
450	 /* Lenovo E41-45 */
451	 .matches = {
452		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
453		DMI_MATCH(DMI_PRODUCT_NAME, "82BK"),
454		},
455	},
456	{
457	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1217249 */
458	 .callback = video_detect_force_native,
459	 /* Apple MacBook Pro 12,1 */
460	 .matches = {
461		DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
462		DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro12,1"),
463		},
464	},
465	{
466	 .callback = video_detect_force_native,
467	 /* Dell Inspiron N4010 */
468	 .matches = {
469		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
470		DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron N4010"),
471		},
472	},
473	{
474	 .callback = video_detect_force_native,
475	 /* Dell Vostro V131 */
476	 .matches = {
477		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
478		DMI_MATCH(DMI_PRODUCT_NAME, "Vostro V131"),
479		},
480	},
481	{
482	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1123661 */
483	 .callback = video_detect_force_native,
484	 /* Dell XPS 17 L702X */
485	 .matches = {
486		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
487		DMI_MATCH(DMI_PRODUCT_NAME, "Dell System XPS L702X"),
488		},
489	},
490	{
491	 .callback = video_detect_force_native,
492	 /* Dell Precision 7510 */
493	 .matches = {
494		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
495		DMI_MATCH(DMI_PRODUCT_NAME, "Precision 7510"),
496		},
497	},
498	{
499	 .callback = video_detect_force_native,
500	 /* Acer Aspire 4810T */
501	 .matches = {
502		DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
503		DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 4810T"),
504		},
505	},
506	{
507	 .callback = video_detect_force_native,
508	 /* Acer Aspire 5738z */
509	 .matches = {
510		DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
511		DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5738"),
512		DMI_MATCH(DMI_BOARD_NAME, "JV50"),
513		},
514	},
515	{
516	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1012674 */
517	 .callback = video_detect_force_native,
518	 /* Acer Aspire 5741 */
519	 .matches = {
520		DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
521		DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5741"),
522		},
523	},
524	{
525	 /* https://bugzilla.kernel.org/show_bug.cgi?id=42993 */
526	 .callback = video_detect_force_native,
527	 /* Acer Aspire 5750 */
528	 .matches = {
529		DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
530		DMI_MATCH(DMI_PRODUCT_NAME, "Aspire 5750"),
531		},
532	},
533	{
534	 /* https://bugzilla.kernel.org/show_bug.cgi?id=42833 */
535	 .callback = video_detect_force_native,
536	 /* Acer Extensa 5235 */
537	 .matches = {
538		DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
539		DMI_MATCH(DMI_PRODUCT_NAME, "Extensa 5235"),
540		},
541	},
542	{
543	 .callback = video_detect_force_native,
544	 /* Acer TravelMate 4750 */
545	 .matches = {
546		DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
547		DMI_MATCH(DMI_PRODUCT_NAME, "TravelMate 4750"),
548		},
549	},
550	{
551	 /* https://bugzilla.kernel.org/show_bug.cgi?id=207835 */
552	 .callback = video_detect_force_native,
553	 /* Acer TravelMate 5735Z */
554	 .matches = {
555		DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
556		DMI_MATCH(DMI_PRODUCT_NAME, "TravelMate 5735Z"),
557		DMI_MATCH(DMI_BOARD_NAME, "BA51_MV"),
558		},
559	},
560	{
561	 /* https://bugzilla.kernel.org/show_bug.cgi?id=36322 */
562	 .callback = video_detect_force_native,
563	 /* Acer TravelMate 5760 */
564	 .matches = {
565		DMI_MATCH(DMI_BOARD_VENDOR, "Acer"),
566		DMI_MATCH(DMI_PRODUCT_NAME, "TravelMate 5760"),
567		},
568	},
569	{
570	 .callback = video_detect_force_native,
571	 /* ASUSTeK COMPUTER INC. GA401 */
572	 .matches = {
573		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
574		DMI_MATCH(DMI_PRODUCT_NAME, "GA401"),
575		},
576	},
577	{
578	 .callback = video_detect_force_native,
579	 /* ASUSTeK COMPUTER INC. GA502 */
580	 .matches = {
581		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
582		DMI_MATCH(DMI_PRODUCT_NAME, "GA502"),
583		},
584	},
585	{
586	 .callback = video_detect_force_native,
587	 /* ASUSTeK COMPUTER INC. GA503 */
588	 .matches = {
589		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
590		DMI_MATCH(DMI_PRODUCT_NAME, "GA503"),
591		},
592	},
593	{
594	 .callback = video_detect_force_native,
595	 /* Asus U46E */
596	 .matches = {
597		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
598		DMI_MATCH(DMI_PRODUCT_NAME, "U46E"),
599		},
600	},
601	{
602	 .callback = video_detect_force_native,
603	 /* Asus UX303UB */
604	 .matches = {
605		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
606		DMI_MATCH(DMI_PRODUCT_NAME, "UX303UB"),
607		},
608	},
609	{
610	 .callback = video_detect_force_native,
611	 /* HP EliteBook 8460p */
612	 .matches = {
613		DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
614		DMI_MATCH(DMI_PRODUCT_NAME, "HP EliteBook 8460p"),
615		},
616	},
617	{
618	 .callback = video_detect_force_native,
619	 /* HP Pavilion g6-1d80nr / B4U19UA */
620	 .matches = {
621		DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
622		DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion g6 Notebook PC"),
623		DMI_MATCH(DMI_PRODUCT_SKU, "B4U19UA"),
624		},
625	},
626	{
627	 .callback = video_detect_force_native,
628	 /* Samsung N150P */
629	 .matches = {
630		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
631		DMI_MATCH(DMI_PRODUCT_NAME, "N150P"),
632		DMI_MATCH(DMI_BOARD_NAME, "N150P"),
633		},
634	},
635	{
636	 .callback = video_detect_force_native,
637	 /* Samsung N145P/N250P/N260P */
638	 .matches = {
639		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
640		DMI_MATCH(DMI_PRODUCT_NAME, "N145P/N250P/N260P"),
641		DMI_MATCH(DMI_BOARD_NAME, "N145P/N250P/N260P"),
642		},
643	},
644	{
645	 .callback = video_detect_force_native,
646	 /* Samsung N250P */
647	 .matches = {
648		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
649		DMI_MATCH(DMI_PRODUCT_NAME, "N250P"),
650		DMI_MATCH(DMI_BOARD_NAME, "N250P"),
651		},
652	},
653	{
654	 /* https://bugzilla.kernel.org/show_bug.cgi?id=202401 */
655	 .callback = video_detect_force_native,
656	 /* Sony Vaio VPCEH3U1E */
657	 .matches = {
658		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
659		DMI_MATCH(DMI_PRODUCT_NAME, "VPCEH3U1E"),
660		},
661	},
662	{
663	 .callback = video_detect_force_native,
664	 /* Sony Vaio VPCY11S1E */
665	 .matches = {
666		DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
667		DMI_MATCH(DMI_PRODUCT_NAME, "VPCY11S1E"),
668		},
669	},
670
671	/*
672	 * These Toshibas have a broken acpi-video interface for brightness
673	 * control. They also have an issue where the panel is off after
674	 * suspend until a special firmware call is made to turn it back
675	 * on. This is handled by the toshiba_acpi kernel module, so that
676	 * module must be enabled for these models to work correctly.
677	 */
678	{
679	 /* https://bugzilla.kernel.org/show_bug.cgi?id=21012 */
680	 .callback = video_detect_force_native,
681	 /* Toshiba Portégé R700 */
682	 .matches = {
683		DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
684		DMI_MATCH(DMI_PRODUCT_NAME, "PORTEGE R700"),
685		},
686	},
687	{
688	 /* Portégé: https://bugs.freedesktop.org/show_bug.cgi?id=82634 */
689	 /* Satellite: https://bugzilla.kernel.org/show_bug.cgi?id=21012 */
690	 .callback = video_detect_force_native,
691	 /* Toshiba Satellite/Portégé R830 */
692	 .matches = {
693		DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
694		DMI_MATCH(DMI_PRODUCT_NAME, "R830"),
695		},
696	},
697	{
698	 .callback = video_detect_force_native,
699	 /* Toshiba Satellite/Portégé Z830 */
700	 .matches = {
701		DMI_MATCH(DMI_SYS_VENDOR, "TOSHIBA"),
702		DMI_MATCH(DMI_PRODUCT_NAME, "Z830"),
703		},
704	},
705
706	/*
707	 * Models which have nvidia-ec-wmi support, but should not use it.
708	 * Note this indicates a likely firmware bug on these models and should
709	 * be revisited if/when Linux gets support for dynamic mux mode.
710	 */
711	{
712	 .callback = video_detect_force_native,
713	 /* Dell G15 5515 */
714	 .matches = {
715		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
716		DMI_MATCH(DMI_PRODUCT_NAME, "Dell G15 5515"),
717		},
718	},
719
720	/*
721	 * Desktops which falsely report a backlight and which our heuristics
722	 * for this do not catch.
723	 */
724	{
725	 .callback = video_detect_force_none,
726	 /* Dell OptiPlex 9020M */
727	 .matches = {
728		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
729		DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 9020M"),
730		},
731	},
732	{
733	 .callback = video_detect_force_none,
734	 /* GIGABYTE GB-BXBT-2807 */
735	 .matches = {
736		DMI_MATCH(DMI_SYS_VENDOR, "GIGABYTE"),
737		DMI_MATCH(DMI_PRODUCT_NAME, "GB-BXBT-2807"),
738		},
739	},
740	{
741	 .callback = video_detect_force_none,
742	 /* MSI MS-7721 */
743	 .matches = {
744		DMI_MATCH(DMI_SYS_VENDOR, "MSI"),
745		DMI_MATCH(DMI_PRODUCT_NAME, "MS-7721"),
746		},
747	},
748	{ },
749};
750
751static bool google_cros_ec_present(void)
 
752{
753	return acpi_dev_found("GOOG0004") || acpi_dev_found("GOOG000C");
 
754}
755
756/*
757 * Windows 8 and newer no longer use the ACPI video interface, so it often
758 * does not work. So on win8+ systems prefer native brightness control.
759 * Chromebooks should always prefer native backlight control.
760 */
761static bool prefer_native_over_acpi_video(void)
762{
763	return acpi_osi_is_win8() || google_cros_ec_present();
 
 
 
 
 
 
 
764}
765
766/*
767 * Determine which type of backlight interface to use on this system,
768 * First check cmdline, then dmi quirks, then do autodetect.
 
 
 
 
 
 
 
 
 
 
769 */
770static enum acpi_backlight_type __acpi_video_get_backlight_type(bool native)
771{
772	static DEFINE_MUTEX(init_mutex);
773	static bool nvidia_wmi_ec_present;
774	static bool apple_gmux_present;
775	static bool native_available;
776	static bool init_done;
777	static long video_caps;
778
779	/* Parse cmdline, dmi and acpi only once */
780	mutex_lock(&init_mutex);
781	if (!init_done) {
782		acpi_video_parse_cmdline();
783		dmi_check_system(video_detect_dmi_table);
784		acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
785				    ACPI_UINT32_MAX, find_video, NULL,
786				    &video_caps, NULL);
787		nvidia_wmi_ec_present = nvidia_wmi_ec_supported();
788		apple_gmux_present = apple_gmux_detect(NULL, NULL);
 
 
 
 
789		init_done = true;
790	}
791	if (native)
792		native_available = true;
793	mutex_unlock(&init_mutex);
794
795	/*
796	 * The below heuristics / detection steps are in order of descending
797	 * presedence. The commandline takes presedence over anything else.
798	 */
799	if (acpi_backlight_cmdline != acpi_backlight_undef)
800		return acpi_backlight_cmdline;
801
802	/* DMI quirks override any autodetection. */
803	if (acpi_backlight_dmi != acpi_backlight_undef)
804		return acpi_backlight_dmi;
805
806	/* Special cases such as nvidia_wmi_ec and apple gmux. */
807	if (nvidia_wmi_ec_present)
808		return acpi_backlight_nvidia_wmi_ec;
809
810	if (apple_gmux_present)
811		return acpi_backlight_apple_gmux;
812
813	/* Use ACPI video if available, except when native should be preferred. */
814	if ((video_caps & ACPI_VIDEO_BACKLIGHT) &&
815	     !(native_available && prefer_native_over_acpi_video()))
816		return acpi_backlight_video;
817
818	/* Use native if available */
819	if (native_available)
820		return acpi_backlight_native;
821
822	/* No ACPI video/native (old hw), use vendor specific fw methods. */
823	return acpi_backlight_vendor;
824}
 
825
826enum acpi_backlight_type acpi_video_get_backlight_type(void)
 
 
 
 
 
827{
828	return __acpi_video_get_backlight_type(false);
 
 
 
829}
830EXPORT_SYMBOL(acpi_video_get_backlight_type);
831
832bool acpi_video_backlight_use_native(void)
833{
834	return __acpi_video_get_backlight_type(true) == acpi_backlight_native;
 
835}
836EXPORT_SYMBOL(acpi_video_backlight_use_native);