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v4.6
  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 const struct dmi_system_id video_detect_dmi_table[] = {
107	/* On Samsung X360, the BIOS will set a flag (VDRV) if generic
108	 * ACPI backlight device is used. This flag will definitively break
109	 * the backlight interface (even the vendor interface) untill next
110	 * reboot. It's why we should prevent video.ko from being used here
111	 * and we can't rely on a later call to acpi_video_unregister().
112	 */
113	{
114	 .callback = video_detect_force_vendor,
115	 .ident = "X360",
116	 .matches = {
117		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
118		DMI_MATCH(DMI_PRODUCT_NAME, "X360"),
119		DMI_MATCH(DMI_BOARD_NAME, "X360"),
120		},
121	},
122	{
123	.callback = video_detect_force_vendor,
124	.ident = "Asus UL30VT",
125	.matches = {
126		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
127		DMI_MATCH(DMI_PRODUCT_NAME, "UL30VT"),
128		},
129	},
130	{
131	.callback = video_detect_force_vendor,
132	.ident = "Asus UL30A",
133	.matches = {
134		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
135		DMI_MATCH(DMI_PRODUCT_NAME, "UL30A"),
136		},
137	},
138
139	/*
140	 * These models have a working acpi_video backlight control, and using
141	 * native backlight causes a regression where backlight does not work
142	 * when userspace is not handling brightness key events. Disable
143	 * native_backlight on these to fix this:
144	 * https://bugzilla.kernel.org/show_bug.cgi?id=81691
145	 */
146	{
147	 .callback = video_detect_force_video,
148	 .ident = "ThinkPad T420",
149	 .matches = {
150		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
151		DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T420"),
152		},
153	},
154	{
155	 .callback = video_detect_force_video,
156	 .ident = "ThinkPad T520",
157	 .matches = {
158		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
159		DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T520"),
160		},
161	},
162	{
163	 .callback = video_detect_force_video,
164	 .ident = "ThinkPad X201s",
165	 .matches = {
166		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
167		DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X201s"),
168		},
169	},
 
 
 
 
 
 
 
 
170
171	/* The native backlight controls do not work on some older machines */
172	{
173	 /* https://bugs.freedesktop.org/show_bug.cgi?id=81515 */
174	 .callback = video_detect_force_video,
175	 .ident = "HP ENVY 15 Notebook",
176	 .matches = {
177		DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
178		DMI_MATCH(DMI_PRODUCT_NAME, "HP ENVY 15 Notebook PC"),
179		},
180	},
181	{
182	 .callback = video_detect_force_video,
183	 .ident = "SAMSUNG 870Z5E/880Z5E/680Z5E",
184	 .matches = {
185		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
186		DMI_MATCH(DMI_PRODUCT_NAME, "870Z5E/880Z5E/680Z5E"),
187		},
188	},
189	{
190	 .callback = video_detect_force_video,
191	 .ident = "SAMSUNG 370R4E/370R4V/370R5E/3570RE/370R5V",
192	 .matches = {
193		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
194		DMI_MATCH(DMI_PRODUCT_NAME,
195			  "370R4E/370R4V/370R5E/3570RE/370R5V"),
196		},
197	},
198	{
199	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1186097 */
200	 .callback = video_detect_force_video,
201	 .ident = "SAMSUNG 3570R/370R/470R/450R/510R/4450RV",
202	 .matches = {
203		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
204		DMI_MATCH(DMI_PRODUCT_NAME,
205			  "3570R/370R/470R/450R/510R/4450RV"),
206		},
207	},
208	{
209	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1094948 */
210	 .callback = video_detect_force_video,
211	 .ident = "SAMSUNG 730U3E/740U3E",
212	 .matches = {
213		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
214		DMI_MATCH(DMI_PRODUCT_NAME, "730U3E/740U3E"),
215		},
216	},
217	{
218	 /* https://bugs.freedesktop.org/show_bug.cgi?id=87286 */
219	 .callback = video_detect_force_video,
220	 .ident = "SAMSUNG 900X3C/900X3D/900X3E/900X4C/900X4D",
221	 .matches = {
222		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
223		DMI_MATCH(DMI_PRODUCT_NAME,
224			  "900X3C/900X3D/900X3E/900X4C/900X4D"),
225		},
226	},
227	{
228	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1272633 */
229	 .callback = video_detect_force_video,
230	 .ident = "Dell XPS14 L421X",
231	 .matches = {
232		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
233		DMI_MATCH(DMI_PRODUCT_NAME, "XPS L421X"),
234		},
235	},
236	{
237	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1163574 */
238	 .callback = video_detect_force_video,
239	 .ident = "Dell XPS15 L521X",
240	 .matches = {
241		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
242		DMI_MATCH(DMI_PRODUCT_NAME, "XPS L521X"),
243		},
244	},
245	{
246	 /* https://bugzilla.kernel.org/show_bug.cgi?id=108971 */
247	 .callback = video_detect_force_video,
248	 .ident = "SAMSUNG 530U4E/540U4E",
249	 .matches = {
250		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
251		DMI_MATCH(DMI_PRODUCT_NAME, "530U4E/540U4E"),
252		},
253	},
254
255	/* Non win8 machines which need native backlight nevertheless */
256	{
257	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1201530 */
258	 .callback = video_detect_force_native,
259	 .ident = "Lenovo Ideapad S405",
260	 .matches = {
261		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
262		DMI_MATCH(DMI_BOARD_NAME, "Lenovo IdeaPad S405"),
263		},
264	},
265	{
266	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1187004 */
267	 .callback = video_detect_force_native,
268	 .ident = "Lenovo Ideapad Z570",
269	 .matches = {
270		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
271		DMI_MATCH(DMI_PRODUCT_NAME, "102434U"),
272		},
273	},
274	{
275	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1217249 */
276	 .callback = video_detect_force_native,
277	 .ident = "Apple MacBook Pro 12,1",
278	 .matches = {
279		DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
280		DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro12,1"),
281		},
282	},
283	{
284	 .callback = video_detect_force_native,
285	 .ident = "Dell Vostro V131",
286	 .matches = {
287		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
288		DMI_MATCH(DMI_PRODUCT_NAME, "Vostro V131"),
289		},
290	},
 
 
 
 
 
 
 
 
 
291	{ },
292};
293
294/* This uses a workqueue to avoid various locking ordering issues */
295static void acpi_video_backlight_notify_work(struct work_struct *work)
296{
297	if (acpi_video_get_backlight_type() != acpi_backlight_video)
298		acpi_video_unregister_backlight();
299}
300
301static int acpi_video_backlight_notify(struct notifier_block *nb,
302				       unsigned long val, void *bd)
303{
304	struct backlight_device *backlight = bd;
305
306	/* A raw bl registering may change video -> native */
307	if (backlight->props.type == BACKLIGHT_RAW &&
308	    val == BACKLIGHT_REGISTERED)
309		schedule_work(&backlight_notify_work);
310
311	return NOTIFY_OK;
312}
313
314/*
315 * Determine which type of backlight interface to use on this system,
316 * First check cmdline, then dmi quirks, then do autodetect.
317 *
318 * The autodetect order is:
319 * 1) Is the acpi-video backlight interface supported ->
320 *  no, use a vendor interface
321 * 2) Is this a win8 "ready" BIOS and do we have a native interface ->
322 *  yes, use a native interface
323 * 3) Else use the acpi-video interface
324 *
325 * Arguably the native on win8 check should be done first, but that would
326 * be a behavior change, which may causes issues.
327 */
328enum acpi_backlight_type acpi_video_get_backlight_type(void)
329{
330	static DEFINE_MUTEX(init_mutex);
331	static bool init_done;
332	static long video_caps;
333
334	/* Parse cmdline, dmi and acpi only once */
335	mutex_lock(&init_mutex);
336	if (!init_done) {
337		acpi_video_parse_cmdline();
338		dmi_check_system(video_detect_dmi_table);
339		acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
340				    ACPI_UINT32_MAX, find_video, NULL,
341				    &video_caps, NULL);
342		INIT_WORK(&backlight_notify_work,
343			  acpi_video_backlight_notify_work);
344		backlight_nb.notifier_call = acpi_video_backlight_notify;
345		backlight_nb.priority = 0;
346		if (backlight_register_notifier(&backlight_nb) == 0)
347			backlight_notifier_registered = true;
348		init_done = true;
349	}
350	mutex_unlock(&init_mutex);
351
352	if (acpi_backlight_cmdline != acpi_backlight_undef)
353		return acpi_backlight_cmdline;
354
355	if (acpi_backlight_dmi != acpi_backlight_undef)
356		return acpi_backlight_dmi;
357
358	if (!(video_caps & ACPI_VIDEO_BACKLIGHT))
359		return acpi_backlight_vendor;
360
361	if (acpi_osi_is_win8() && backlight_device_registered(BACKLIGHT_RAW))
362		return acpi_backlight_native;
363
364	return acpi_backlight_video;
365}
366EXPORT_SYMBOL(acpi_video_get_backlight_type);
367
368/*
369 * Set the preferred backlight interface type based on DMI info.
370 * This function allows DMI blacklists to be implemented by external
371 * platform drivers instead of putting a big blacklist in video_detect.c
372 */
373void acpi_video_set_dmi_backlight_type(enum acpi_backlight_type type)
374{
375	acpi_backlight_dmi = type;
376	/* Remove acpi-video backlight interface if it is no longer desired */
377	if (acpi_video_get_backlight_type() != acpi_backlight_video)
378		acpi_video_unregister_backlight();
379}
380EXPORT_SYMBOL(acpi_video_set_dmi_backlight_type);
381
382void __exit acpi_video_detect_exit(void)
383{
384	if (backlight_notifier_registered)
385		backlight_unregister_notifier(&backlight_nb);
386}
v4.10.11
  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 const struct dmi_system_id video_detect_dmi_table[] = {
107	/* On Samsung X360, the BIOS will set a flag (VDRV) if generic
108	 * ACPI backlight device is used. This flag will definitively break
109	 * the backlight interface (even the vendor interface) untill next
110	 * reboot. It's why we should prevent video.ko from being used here
111	 * and we can't rely on a later call to acpi_video_unregister().
112	 */
113	{
114	 .callback = video_detect_force_vendor,
115	 .ident = "X360",
116	 .matches = {
117		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
118		DMI_MATCH(DMI_PRODUCT_NAME, "X360"),
119		DMI_MATCH(DMI_BOARD_NAME, "X360"),
120		},
121	},
122	{
123	.callback = video_detect_force_vendor,
124	.ident = "Asus UL30VT",
125	.matches = {
126		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
127		DMI_MATCH(DMI_PRODUCT_NAME, "UL30VT"),
128		},
129	},
130	{
131	.callback = video_detect_force_vendor,
132	.ident = "Asus UL30A",
133	.matches = {
134		DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
135		DMI_MATCH(DMI_PRODUCT_NAME, "UL30A"),
136		},
137	},
138
139	/*
140	 * These models have a working acpi_video backlight control, and using
141	 * native backlight causes a regression where backlight does not work
142	 * when userspace is not handling brightness key events. Disable
143	 * native_backlight on these to fix this:
144	 * https://bugzilla.kernel.org/show_bug.cgi?id=81691
145	 */
146	{
147	 .callback = video_detect_force_video,
148	 .ident = "ThinkPad T420",
149	 .matches = {
150		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
151		DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T420"),
152		},
153	},
154	{
155	 .callback = video_detect_force_video,
156	 .ident = "ThinkPad T520",
157	 .matches = {
158		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
159		DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T520"),
160		},
161	},
162	{
163	 .callback = video_detect_force_video,
164	 .ident = "ThinkPad X201s",
165	 .matches = {
166		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
167		DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X201s"),
168		},
169	},
170        {
171         .callback = video_detect_force_video,
172         .ident = "ThinkPad X201T",
173         .matches = {
174                DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
175                DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X201T"),
176                },
177        },
178
179	/* The native backlight controls do not work on some older machines */
180	{
181	 /* https://bugs.freedesktop.org/show_bug.cgi?id=81515 */
182	 .callback = video_detect_force_video,
183	 .ident = "HP ENVY 15 Notebook",
184	 .matches = {
185		DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
186		DMI_MATCH(DMI_PRODUCT_NAME, "HP ENVY 15 Notebook PC"),
187		},
188	},
189	{
190	 .callback = video_detect_force_video,
191	 .ident = "SAMSUNG 870Z5E/880Z5E/680Z5E",
192	 .matches = {
193		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
194		DMI_MATCH(DMI_PRODUCT_NAME, "870Z5E/880Z5E/680Z5E"),
195		},
196	},
197	{
198	 .callback = video_detect_force_video,
199	 .ident = "SAMSUNG 370R4E/370R4V/370R5E/3570RE/370R5V",
200	 .matches = {
201		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
202		DMI_MATCH(DMI_PRODUCT_NAME,
203			  "370R4E/370R4V/370R5E/3570RE/370R5V"),
204		},
205	},
206	{
207	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1186097 */
208	 .callback = video_detect_force_video,
209	 .ident = "SAMSUNG 3570R/370R/470R/450R/510R/4450RV",
210	 .matches = {
211		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
212		DMI_MATCH(DMI_PRODUCT_NAME,
213			  "3570R/370R/470R/450R/510R/4450RV"),
214		},
215	},
216	{
217	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1094948 */
218	 .callback = video_detect_force_video,
219	 .ident = "SAMSUNG 730U3E/740U3E",
220	 .matches = {
221		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
222		DMI_MATCH(DMI_PRODUCT_NAME, "730U3E/740U3E"),
223		},
224	},
225	{
226	 /* https://bugs.freedesktop.org/show_bug.cgi?id=87286 */
227	 .callback = video_detect_force_video,
228	 .ident = "SAMSUNG 900X3C/900X3D/900X3E/900X4C/900X4D",
229	 .matches = {
230		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
231		DMI_MATCH(DMI_PRODUCT_NAME,
232			  "900X3C/900X3D/900X3E/900X4C/900X4D"),
233		},
234	},
235	{
236	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1272633 */
237	 .callback = video_detect_force_video,
238	 .ident = "Dell XPS14 L421X",
239	 .matches = {
240		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
241		DMI_MATCH(DMI_PRODUCT_NAME, "XPS L421X"),
242		},
243	},
244	{
245	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1163574 */
246	 .callback = video_detect_force_video,
247	 .ident = "Dell XPS15 L521X",
248	 .matches = {
249		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
250		DMI_MATCH(DMI_PRODUCT_NAME, "XPS L521X"),
251		},
252	},
253	{
254	 /* https://bugzilla.kernel.org/show_bug.cgi?id=108971 */
255	 .callback = video_detect_force_video,
256	 .ident = "SAMSUNG 530U4E/540U4E",
257	 .matches = {
258		DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
259		DMI_MATCH(DMI_PRODUCT_NAME, "530U4E/540U4E"),
260		},
261	},
262
263	/* Non win8 machines which need native backlight nevertheless */
264	{
265	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1201530 */
266	 .callback = video_detect_force_native,
267	 .ident = "Lenovo Ideapad S405",
268	 .matches = {
269		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
270		DMI_MATCH(DMI_BOARD_NAME, "Lenovo IdeaPad S405"),
271		},
272	},
273	{
274	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1187004 */
275	 .callback = video_detect_force_native,
276	 .ident = "Lenovo Ideapad Z570",
277	 .matches = {
278		DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
279		DMI_MATCH(DMI_PRODUCT_NAME, "102434U"),
280		},
281	},
282	{
283	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1217249 */
284	 .callback = video_detect_force_native,
285	 .ident = "Apple MacBook Pro 12,1",
286	 .matches = {
287		DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
288		DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro12,1"),
289		},
290	},
291	{
292	 .callback = video_detect_force_native,
293	 .ident = "Dell Vostro V131",
294	 .matches = {
295		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
296		DMI_MATCH(DMI_PRODUCT_NAME, "Vostro V131"),
297		},
298	},
299	{
300	 /* https://bugzilla.redhat.com/show_bug.cgi?id=1123661 */
301	 .callback = video_detect_force_native,
302	 .ident = "Dell XPS 17 L702X",
303	 .matches = {
304		DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
305		DMI_MATCH(DMI_PRODUCT_NAME, "Dell System XPS L702X"),
306		},
307	},
308	{ },
309};
310
311/* This uses a workqueue to avoid various locking ordering issues */
312static void acpi_video_backlight_notify_work(struct work_struct *work)
313{
314	if (acpi_video_get_backlight_type() != acpi_backlight_video)
315		acpi_video_unregister_backlight();
316}
317
318static int acpi_video_backlight_notify(struct notifier_block *nb,
319				       unsigned long val, void *bd)
320{
321	struct backlight_device *backlight = bd;
322
323	/* A raw bl registering may change video -> native */
324	if (backlight->props.type == BACKLIGHT_RAW &&
325	    val == BACKLIGHT_REGISTERED)
326		schedule_work(&backlight_notify_work);
327
328	return NOTIFY_OK;
329}
330
331/*
332 * Determine which type of backlight interface to use on this system,
333 * First check cmdline, then dmi quirks, then do autodetect.
334 *
335 * The autodetect order is:
336 * 1) Is the acpi-video backlight interface supported ->
337 *  no, use a vendor interface
338 * 2) Is this a win8 "ready" BIOS and do we have a native interface ->
339 *  yes, use a native interface
340 * 3) Else use the acpi-video interface
341 *
342 * Arguably the native on win8 check should be done first, but that would
343 * be a behavior change, which may causes issues.
344 */
345enum acpi_backlight_type acpi_video_get_backlight_type(void)
346{
347	static DEFINE_MUTEX(init_mutex);
348	static bool init_done;
349	static long video_caps;
350
351	/* Parse cmdline, dmi and acpi only once */
352	mutex_lock(&init_mutex);
353	if (!init_done) {
354		acpi_video_parse_cmdline();
355		dmi_check_system(video_detect_dmi_table);
356		acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
357				    ACPI_UINT32_MAX, find_video, NULL,
358				    &video_caps, NULL);
359		INIT_WORK(&backlight_notify_work,
360			  acpi_video_backlight_notify_work);
361		backlight_nb.notifier_call = acpi_video_backlight_notify;
362		backlight_nb.priority = 0;
363		if (backlight_register_notifier(&backlight_nb) == 0)
364			backlight_notifier_registered = true;
365		init_done = true;
366	}
367	mutex_unlock(&init_mutex);
368
369	if (acpi_backlight_cmdline != acpi_backlight_undef)
370		return acpi_backlight_cmdline;
371
372	if (acpi_backlight_dmi != acpi_backlight_undef)
373		return acpi_backlight_dmi;
374
375	if (!(video_caps & ACPI_VIDEO_BACKLIGHT))
376		return acpi_backlight_vendor;
377
378	if (acpi_osi_is_win8() && backlight_device_get_by_type(BACKLIGHT_RAW))
379		return acpi_backlight_native;
380
381	return acpi_backlight_video;
382}
383EXPORT_SYMBOL(acpi_video_get_backlight_type);
384
385/*
386 * Set the preferred backlight interface type based on DMI info.
387 * This function allows DMI blacklists to be implemented by external
388 * platform drivers instead of putting a big blacklist in video_detect.c
389 */
390void acpi_video_set_dmi_backlight_type(enum acpi_backlight_type type)
391{
392	acpi_backlight_dmi = type;
393	/* Remove acpi-video backlight interface if it is no longer desired */
394	if (acpi_video_get_backlight_type() != acpi_backlight_video)
395		acpi_video_unregister_backlight();
396}
397EXPORT_SYMBOL(acpi_video_set_dmi_backlight_type);
398
399void __exit acpi_video_detect_exit(void)
400{
401	if (backlight_notifier_registered)
402		backlight_unregister_notifier(&backlight_nb);
403}