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 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().
114 .callback
= video_detect_force_vendor
,
117 DMI_MATCH(DMI_SYS_VENDOR
, "SAMSUNG ELECTRONICS CO., LTD."),
118 DMI_MATCH(DMI_PRODUCT_NAME
, "X360"),
119 DMI_MATCH(DMI_BOARD_NAME
, "X360"),
123 .callback
= video_detect_force_vendor
,
124 .ident
= "Asus UL30VT",
126 DMI_MATCH(DMI_SYS_VENDOR
, "ASUSTeK Computer Inc."),
127 DMI_MATCH(DMI_PRODUCT_NAME
, "UL30VT"),
131 .callback
= video_detect_force_vendor
,
132 .ident
= "Asus UL30A",
134 DMI_MATCH(DMI_SYS_VENDOR
, "ASUSTeK Computer Inc."),
135 DMI_MATCH(DMI_PRODUCT_NAME
, "UL30A"),
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
147 .callback
= video_detect_force_video
,
148 .ident
= "ThinkPad T420",
150 DMI_MATCH(DMI_SYS_VENDOR
, "LENOVO"),
151 DMI_MATCH(DMI_PRODUCT_VERSION
, "ThinkPad T420"),
155 .callback
= video_detect_force_video
,
156 .ident
= "ThinkPad T520",
158 DMI_MATCH(DMI_SYS_VENDOR
, "LENOVO"),
159 DMI_MATCH(DMI_PRODUCT_VERSION
, "ThinkPad T520"),
163 .callback
= video_detect_force_video
,
164 .ident
= "ThinkPad X201s",
166 DMI_MATCH(DMI_SYS_VENDOR
, "LENOVO"),
167 DMI_MATCH(DMI_PRODUCT_VERSION
, "ThinkPad X201s"),
171 /* The native backlight controls do not work on some older machines */
173 /* https://bugs.freedesktop.org/show_bug.cgi?id=81515 */
174 .callback
= video_detect_force_video
,
175 .ident
= "HP ENVY 15 Notebook",
177 DMI_MATCH(DMI_SYS_VENDOR
, "Hewlett-Packard"),
178 DMI_MATCH(DMI_PRODUCT_NAME
, "HP ENVY 15 Notebook PC"),
182 .callback
= video_detect_force_video
,
183 .ident
= "SAMSUNG 870Z5E/880Z5E/680Z5E",
185 DMI_MATCH(DMI_SYS_VENDOR
, "SAMSUNG ELECTRONICS CO., LTD."),
186 DMI_MATCH(DMI_PRODUCT_NAME
, "870Z5E/880Z5E/680Z5E"),
190 .callback
= video_detect_force_video
,
191 .ident
= "SAMSUNG 370R4E/370R4V/370R5E/3570RE/370R5V",
193 DMI_MATCH(DMI_SYS_VENDOR
, "SAMSUNG ELECTRONICS CO., LTD."),
194 DMI_MATCH(DMI_PRODUCT_NAME
,
195 "370R4E/370R4V/370R5E/3570RE/370R5V"),
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",
203 DMI_MATCH(DMI_SYS_VENDOR
, "SAMSUNG ELECTRONICS CO., LTD."),
204 DMI_MATCH(DMI_PRODUCT_NAME
,
205 "3570R/370R/470R/450R/510R/4450RV"),
209 /* https://bugzilla.redhat.com/show_bug.cgi?id=1557060 */
210 .callback
= video_detect_force_video
,
211 .ident
= "SAMSUNG 670Z5E",
213 DMI_MATCH(DMI_SYS_VENDOR
, "SAMSUNG ELECTRONICS CO., LTD."),
214 DMI_MATCH(DMI_PRODUCT_NAME
, "670Z5E"),
218 /* https://bugzilla.redhat.com/show_bug.cgi?id=1094948 */
219 .callback
= video_detect_force_video
,
220 .ident
= "SAMSUNG 730U3E/740U3E",
222 DMI_MATCH(DMI_SYS_VENDOR
, "SAMSUNG ELECTRONICS CO., LTD."),
223 DMI_MATCH(DMI_PRODUCT_NAME
, "730U3E/740U3E"),
227 /* https://bugs.freedesktop.org/show_bug.cgi?id=87286 */
228 .callback
= video_detect_force_video
,
229 .ident
= "SAMSUNG 900X3C/900X3D/900X3E/900X4C/900X4D",
231 DMI_MATCH(DMI_SYS_VENDOR
, "SAMSUNG ELECTRONICS CO., LTD."),
232 DMI_MATCH(DMI_PRODUCT_NAME
,
233 "900X3C/900X3D/900X3E/900X4C/900X4D"),
237 /* https://bugzilla.redhat.com/show_bug.cgi?id=1272633 */
238 .callback
= video_detect_force_video
,
239 .ident
= "Dell XPS14 L421X",
241 DMI_MATCH(DMI_SYS_VENDOR
, "Dell Inc."),
242 DMI_MATCH(DMI_PRODUCT_NAME
, "XPS L421X"),
246 /* https://bugzilla.redhat.com/show_bug.cgi?id=1163574 */
247 .callback
= video_detect_force_video
,
248 .ident
= "Dell XPS15 L521X",
250 DMI_MATCH(DMI_SYS_VENDOR
, "Dell Inc."),
251 DMI_MATCH(DMI_PRODUCT_NAME
, "XPS L521X"),
255 /* Non win8 machines which need native backlight nevertheless */
257 /* https://bugzilla.redhat.com/show_bug.cgi?id=1201530 */
258 .callback
= video_detect_force_native
,
259 .ident
= "Lenovo Ideapad S405",
261 DMI_MATCH(DMI_SYS_VENDOR
, "LENOVO"),
262 DMI_MATCH(DMI_BOARD_NAME
, "Lenovo IdeaPad S405"),
266 /* https://bugzilla.redhat.com/show_bug.cgi?id=1187004 */
267 .callback
= video_detect_force_native
,
268 .ident
= "Lenovo Ideapad Z570",
270 DMI_MATCH(DMI_SYS_VENDOR
, "LENOVO"),
271 DMI_MATCH(DMI_PRODUCT_NAME
, "102434U"),
275 /* https://bugzilla.redhat.com/show_bug.cgi?id=1217249 */
276 .callback
= video_detect_force_native
,
277 .ident
= "Apple MacBook Pro 12,1",
279 DMI_MATCH(DMI_SYS_VENDOR
, "Apple Inc."),
280 DMI_MATCH(DMI_PRODUCT_NAME
, "MacBookPro12,1"),
284 /* https://bugzilla.redhat.com/show_bug.cgi?id=1123661 */
285 .callback
= video_detect_force_native
,
286 .ident
= "Dell XPS 17 L702X",
288 DMI_MATCH(DMI_SYS_VENDOR
, "Dell Inc."),
289 DMI_MATCH(DMI_PRODUCT_NAME
, "Dell System XPS L702X"),
293 /* https://bugzilla.redhat.com/show_bug.cgi?id=1204476 */
294 /* https://bugs.launchpad.net/ubuntu/+source/linux-lts-trusty/+bug/1416940 */
295 .callback
= video_detect_force_native
,
296 .ident
= "HP Pavilion dv6",
298 DMI_MATCH(DMI_SYS_VENDOR
, "Hewlett-Packard"),
299 DMI_MATCH(DMI_PRODUCT_NAME
, "HP Pavilion dv6 Notebook PC"),
306 /* This uses a workqueue to avoid various locking ordering issues */
307 static void acpi_video_backlight_notify_work(struct work_struct
*work
)
309 if (acpi_video_get_backlight_type() != acpi_backlight_video
)
310 acpi_video_unregister_backlight();
313 static int acpi_video_backlight_notify(struct notifier_block
*nb
,
314 unsigned long val
, void *bd
)
316 struct backlight_device
*backlight
= bd
;
318 /* A raw bl registering may change video -> native */
319 if (backlight
->props
.type
== BACKLIGHT_RAW
&&
320 val
== BACKLIGHT_REGISTERED
)
321 schedule_work(&backlight_notify_work
);
327 * Determine which type of backlight interface to use on this system,
328 * First check cmdline, then dmi quirks, then do autodetect.
330 * The autodetect order is:
331 * 1) Is the acpi-video backlight interface supported ->
332 * no, use a vendor interface
333 * 2) Is this a win8 "ready" BIOS and do we have a native interface ->
334 * yes, use a native interface
335 * 3) Else use the acpi-video interface
337 * Arguably the native on win8 check should be done first, but that would
338 * be a behavior change, which may causes issues.
340 enum acpi_backlight_type
acpi_video_get_backlight_type(void)
342 static DEFINE_MUTEX(init_mutex
);
343 static bool init_done
;
344 static long video_caps
;
346 /* Parse cmdline, dmi and acpi only once */
347 mutex_lock(&init_mutex
);
349 acpi_video_parse_cmdline();
350 dmi_check_system(video_detect_dmi_table
);
351 acpi_walk_namespace(ACPI_TYPE_DEVICE
, ACPI_ROOT_OBJECT
,
352 ACPI_UINT32_MAX
, find_video
, NULL
,
354 INIT_WORK(&backlight_notify_work
,
355 acpi_video_backlight_notify_work
);
356 backlight_nb
.notifier_call
= acpi_video_backlight_notify
;
357 backlight_nb
.priority
= 0;
358 if (backlight_register_notifier(&backlight_nb
) == 0)
359 backlight_notifier_registered
= true;
362 mutex_unlock(&init_mutex
);
364 if (acpi_backlight_cmdline
!= acpi_backlight_undef
)
365 return acpi_backlight_cmdline
;
367 if (acpi_backlight_dmi
!= acpi_backlight_undef
)
368 return acpi_backlight_dmi
;
370 if (!(video_caps
& ACPI_VIDEO_BACKLIGHT
))
371 return acpi_backlight_vendor
;
373 if (acpi_osi_is_win8() && backlight_device_registered(BACKLIGHT_RAW
))
374 return acpi_backlight_native
;
376 return acpi_backlight_video
;
378 EXPORT_SYMBOL(acpi_video_get_backlight_type
);
381 * Set the preferred backlight interface type based on DMI info.
382 * This function allows DMI blacklists to be implemented by external
383 * platform drivers instead of putting a big blacklist in video_detect.c
385 void acpi_video_set_dmi_backlight_type(enum acpi_backlight_type type
)
387 acpi_backlight_dmi
= type
;
388 /* Remove acpi-video backlight interface if it is no longer desired */
389 if (acpi_video_get_backlight_type() != acpi_backlight_video
)
390 acpi_video_unregister_backlight();
392 EXPORT_SYMBOL(acpi_video_set_dmi_backlight_type
);
394 void __exit
acpi_video_detect_exit(void)
396 if (backlight_notifier_registered
)
397 backlight_unregister_notifier(&backlight_nb
);