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>
7 * May be copied or modified under the terms of the GNU General Public License
10 * After PCI devices are glued with ACPI devices
11 * acpi_get_pci_dev() can be called to identify ACPI graphics
12 * devices for which a real graphics card is plugged in
14 * Depending on whether ACPI graphics extensions (cmp. ACPI spec Appendix B)
15 * are available, video.ko should be used to handle the device.
17 * Otherwise vendor specific drivers like thinkpad_acpi, asus-laptop,
18 * sony_acpi,... can take care about backlight brightness.
20 * Backlight drivers can use acpi_video_get_backlight_type() to determine
21 * which driver should handle the backlight.
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.
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>
38 ACPI_MODULE_NAME("video");
39 #define _COMPONENT ACPI_VIDEO_COMPONENT
41 void acpi_video_unregister_backlight(void);
43 static bool backlight_notifier_registered;
44 static struct notifier_block backlight_nb;
45 static struct work_struct backlight_notify_work;
47 static enum acpi_backlight_type acpi_backlight_cmdline = acpi_backlight_undef;
48 static enum acpi_backlight_type acpi_backlight_dmi = acpi_backlight_undef;
50 static void acpi_video_parse_cmdline(void)
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;
63 find_video(acpi_handle handle, u32 lvl, void *context, void **rv)
67 struct acpi_device *acpi_dev;
69 static const struct acpi_device_id video_ids[] = {
73 if (acpi_bus_get_device(handle, &acpi_dev))
76 if (!acpi_match_device_ids(acpi_dev, video_ids)) {
77 dev = acpi_get_pci_dev(handle);
81 *cap |= acpi_is_video_device(handle);
86 /* Force to use vendor driver when the ACPI device is known to be
88 static int video_detect_force_vendor(const struct dmi_system_id *d)
90 acpi_backlight_dmi = acpi_backlight_vendor;
94 static int video_detect_force_video(const struct dmi_system_id *d)
96 acpi_backlight_dmi = acpi_backlight_video;
100 static int video_detect_force_native(const struct dmi_system_id *d)
102 acpi_backlight_dmi = acpi_backlight_native;
106 static int video_detect_force_none(const struct dmi_system_id *d)
108 acpi_backlight_dmi = acpi_backlight_none;
112 static 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) untill 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().
120 .callback = video_detect_force_vendor,
123 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
124 DMI_MATCH(DMI_PRODUCT_NAME, "X360"),
125 DMI_MATCH(DMI_BOARD_NAME, "X360"),
129 .callback = video_detect_force_vendor,
130 .ident = "Asus UL30VT",
132 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
133 DMI_MATCH(DMI_PRODUCT_NAME, "UL30VT"),
137 .callback = video_detect_force_vendor,
138 .ident = "Asus UL30A",
140 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
141 DMI_MATCH(DMI_PRODUCT_NAME, "UL30A"),
146 * These models have a working acpi_video backlight control, and using
147 * native backlight causes a regression where backlight does not work
148 * when userspace is not handling brightness key events. Disable
149 * native_backlight on these to fix this:
150 * https://bugzilla.kernel.org/show_bug.cgi?id=81691
153 .callback = video_detect_force_video,
154 .ident = "ThinkPad T420",
156 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
157 DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T420"),
161 .callback = video_detect_force_video,
162 .ident = "ThinkPad T520",
164 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
165 DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T520"),
169 .callback = video_detect_force_video,
170 .ident = "ThinkPad X201s",
172 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
173 DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X201s"),
177 .callback = video_detect_force_video,
178 .ident = "ThinkPad X201T",
180 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
181 DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X201T"),
185 /* The native backlight controls do not work on some older machines */
187 /* https://bugs.freedesktop.org/show_bug.cgi?id=81515 */
188 .callback = video_detect_force_video,
189 .ident = "HP ENVY 15 Notebook",
191 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
192 DMI_MATCH(DMI_PRODUCT_NAME, "HP ENVY 15 Notebook PC"),
196 .callback = video_detect_force_video,
197 .ident = "SAMSUNG 870Z5E/880Z5E/680Z5E",
199 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
200 DMI_MATCH(DMI_PRODUCT_NAME, "870Z5E/880Z5E/680Z5E"),
204 .callback = video_detect_force_video,
205 .ident = "SAMSUNG 370R4E/370R4V/370R5E/3570RE/370R5V",
207 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
208 DMI_MATCH(DMI_PRODUCT_NAME,
209 "370R4E/370R4V/370R5E/3570RE/370R5V"),
213 /* https://bugzilla.redhat.com/show_bug.cgi?id=1186097 */
214 .callback = video_detect_force_video,
215 .ident = "SAMSUNG 3570R/370R/470R/450R/510R/4450RV",
217 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
218 DMI_MATCH(DMI_PRODUCT_NAME,
219 "3570R/370R/470R/450R/510R/4450RV"),
223 /* https://bugzilla.redhat.com/show_bug.cgi?id=1094948 */
224 .callback = video_detect_force_video,
225 .ident = "SAMSUNG 730U3E/740U3E",
227 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
228 DMI_MATCH(DMI_PRODUCT_NAME, "730U3E/740U3E"),
232 /* https://bugs.freedesktop.org/show_bug.cgi?id=87286 */
233 .callback = video_detect_force_video,
234 .ident = "SAMSUNG 900X3C/900X3D/900X3E/900X4C/900X4D",
236 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
237 DMI_MATCH(DMI_PRODUCT_NAME,
238 "900X3C/900X3D/900X3E/900X4C/900X4D"),
242 /* https://bugzilla.redhat.com/show_bug.cgi?id=1272633 */
243 .callback = video_detect_force_video,
244 .ident = "Dell XPS14 L421X",
246 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
247 DMI_MATCH(DMI_PRODUCT_NAME, "XPS L421X"),
251 /* https://bugzilla.redhat.com/show_bug.cgi?id=1163574 */
252 .callback = video_detect_force_video,
253 .ident = "Dell XPS15 L521X",
255 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
256 DMI_MATCH(DMI_PRODUCT_NAME, "XPS L521X"),
260 /* https://bugzilla.kernel.org/show_bug.cgi?id=108971 */
261 .callback = video_detect_force_video,
262 .ident = "SAMSUNG 530U4E/540U4E",
264 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
265 DMI_MATCH(DMI_PRODUCT_NAME, "530U4E/540U4E"),
269 /* Non win8 machines which need native backlight nevertheless */
271 /* https://bugzilla.redhat.com/show_bug.cgi?id=1201530 */
272 .callback = video_detect_force_native,
273 .ident = "Lenovo Ideapad S405",
275 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
276 DMI_MATCH(DMI_BOARD_NAME, "Lenovo IdeaPad S405"),
280 /* https://bugzilla.redhat.com/show_bug.cgi?id=1187004 */
281 .callback = video_detect_force_native,
282 .ident = "Lenovo Ideapad Z570",
284 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
285 DMI_MATCH(DMI_PRODUCT_NAME, "102434U"),
289 /* https://bugzilla.redhat.com/show_bug.cgi?id=1217249 */
290 .callback = video_detect_force_native,
291 .ident = "Apple MacBook Pro 12,1",
293 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
294 DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro12,1"),
298 .callback = video_detect_force_native,
299 .ident = "Dell Vostro V131",
301 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
302 DMI_MATCH(DMI_PRODUCT_NAME, "Vostro V131"),
306 /* https://bugzilla.redhat.com/show_bug.cgi?id=1123661 */
307 .callback = video_detect_force_native,
308 .ident = "Dell XPS 17 L702X",
310 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
311 DMI_MATCH(DMI_PRODUCT_NAME, "Dell System XPS L702X"),
315 .callback = video_detect_force_native,
316 .ident = "Dell Precision 7510",
318 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
319 DMI_MATCH(DMI_PRODUCT_NAME, "Precision 7510"),
323 .callback = video_detect_force_none,
324 .ident = "Dell OptiPlex 9020M",
326 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
327 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 9020M"),
333 /* This uses a workqueue to avoid various locking ordering issues */
334 static void acpi_video_backlight_notify_work(struct work_struct *work)
336 if (acpi_video_get_backlight_type() != acpi_backlight_video)
337 acpi_video_unregister_backlight();
340 static int acpi_video_backlight_notify(struct notifier_block *nb,
341 unsigned long val, void *bd)
343 struct backlight_device *backlight = bd;
345 /* A raw bl registering may change video -> native */
346 if (backlight->props.type == BACKLIGHT_RAW &&
347 val == BACKLIGHT_REGISTERED)
348 schedule_work(&backlight_notify_work);
354 * Determine which type of backlight interface to use on this system,
355 * First check cmdline, then dmi quirks, then do autodetect.
357 * The autodetect order is:
358 * 1) Is the acpi-video backlight interface supported ->
359 * no, use a vendor interface
360 * 2) Is this a win8 "ready" BIOS and do we have a native interface ->
361 * yes, use a native interface
362 * 3) Else use the acpi-video interface
364 * Arguably the native on win8 check should be done first, but that would
365 * be a behavior change, which may causes issues.
367 enum acpi_backlight_type acpi_video_get_backlight_type(void)
369 static DEFINE_MUTEX(init_mutex);
370 static bool init_done;
371 static long video_caps;
373 /* Parse cmdline, dmi and acpi only once */
374 mutex_lock(&init_mutex);
376 acpi_video_parse_cmdline();
377 dmi_check_system(video_detect_dmi_table);
378 acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
379 ACPI_UINT32_MAX, find_video, NULL,
381 INIT_WORK(&backlight_notify_work,
382 acpi_video_backlight_notify_work);
383 backlight_nb.notifier_call = acpi_video_backlight_notify;
384 backlight_nb.priority = 0;
385 if (backlight_register_notifier(&backlight_nb) == 0)
386 backlight_notifier_registered = true;
389 mutex_unlock(&init_mutex);
391 if (acpi_backlight_cmdline != acpi_backlight_undef)
392 return acpi_backlight_cmdline;
394 if (acpi_backlight_dmi != acpi_backlight_undef)
395 return acpi_backlight_dmi;
397 if (!(video_caps & ACPI_VIDEO_BACKLIGHT))
398 return acpi_backlight_vendor;
400 if (acpi_osi_is_win8() && backlight_device_get_by_type(BACKLIGHT_RAW))
401 return acpi_backlight_native;
403 return acpi_backlight_video;
405 EXPORT_SYMBOL(acpi_video_get_backlight_type);
408 * Set the preferred backlight interface type based on DMI info.
409 * This function allows DMI blacklists to be implemented by external
410 * platform drivers instead of putting a big blacklist in video_detect.c
412 void acpi_video_set_dmi_backlight_type(enum acpi_backlight_type type)
414 acpi_backlight_dmi = type;
415 /* Remove acpi-video backlight interface if it is no longer desired */
416 if (acpi_video_get_backlight_type() != acpi_backlight_video)
417 acpi_video_unregister_backlight();
419 EXPORT_SYMBOL(acpi_video_set_dmi_backlight_type);
421 void __exit acpi_video_detect_exit(void)
423 if (backlight_notifier_registered)
424 backlight_unregister_notifier(&backlight_nb);