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 <acpi/video.h>
37 ACPI_MODULE_NAME("video");
38 #define _COMPONENT ACPI_VIDEO_COMPONENT
40 void acpi_video_unregister_backlight(void);
42 static bool backlight_notifier_registered
;
43 static struct notifier_block backlight_nb
;
45 static enum acpi_backlight_type acpi_backlight_cmdline
= acpi_backlight_undef
;
46 static enum acpi_backlight_type acpi_backlight_dmi
= acpi_backlight_undef
;
48 static void acpi_video_parse_cmdline(void)
50 if (!strcmp("vendor", acpi_video_backlight_string
))
51 acpi_backlight_cmdline
= acpi_backlight_vendor
;
52 if (!strcmp("video", acpi_video_backlight_string
))
53 acpi_backlight_cmdline
= acpi_backlight_video
;
54 if (!strcmp("native", acpi_video_backlight_string
))
55 acpi_backlight_cmdline
= acpi_backlight_native
;
56 if (!strcmp("none", acpi_video_backlight_string
))
57 acpi_backlight_cmdline
= acpi_backlight_none
;
61 find_video(acpi_handle handle
, u32 lvl
, void *context
, void **rv
)
65 struct acpi_device
*acpi_dev
;
67 static const struct acpi_device_id video_ids
[] = {
71 if (acpi_bus_get_device(handle
, &acpi_dev
))
74 if (!acpi_match_device_ids(acpi_dev
, video_ids
)) {
75 dev
= acpi_get_pci_dev(handle
);
79 *cap
|= acpi_is_video_device(handle
);
84 /* Force to use vendor driver when the ACPI device is known to be
86 static int video_detect_force_vendor(const struct dmi_system_id
*d
)
88 acpi_backlight_dmi
= acpi_backlight_vendor
;
92 static int video_detect_force_video(const struct dmi_system_id
*d
)
94 acpi_backlight_dmi
= acpi_backlight_video
;
98 static int video_detect_force_native(const struct dmi_system_id
*d
)
100 acpi_backlight_dmi
= acpi_backlight_native
;
104 static const struct dmi_system_id video_detect_dmi_table
[] = {
105 /* On Samsung X360, the BIOS will set a flag (VDRV) if generic
106 * ACPI backlight device is used. This flag will definitively break
107 * the backlight interface (even the vendor interface) untill next
108 * reboot. It's why we should prevent video.ko from being used here
109 * and we can't rely on a later call to acpi_video_unregister().
112 .callback
= video_detect_force_vendor
,
115 DMI_MATCH(DMI_SYS_VENDOR
, "SAMSUNG ELECTRONICS CO., LTD."),
116 DMI_MATCH(DMI_PRODUCT_NAME
, "X360"),
117 DMI_MATCH(DMI_BOARD_NAME
, "X360"),
121 .callback
= video_detect_force_vendor
,
122 .ident
= "Asus UL30VT",
124 DMI_MATCH(DMI_SYS_VENDOR
, "ASUSTeK Computer Inc."),
125 DMI_MATCH(DMI_PRODUCT_NAME
, "UL30VT"),
129 .callback
= video_detect_force_vendor
,
130 .ident
= "Asus UL30A",
132 DMI_MATCH(DMI_SYS_VENDOR
, "ASUSTeK Computer Inc."),
133 DMI_MATCH(DMI_PRODUCT_NAME
, "UL30A"),
137 .callback
= video_detect_force_vendor
,
138 .ident
= "Dell Inspiron 5737",
140 DMI_MATCH(DMI_SYS_VENDOR
, "Dell Inc."),
141 DMI_MATCH(DMI_PRODUCT_NAME
, "Inspiron 5737"),
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 /* The native backlight controls do not work on some older machines */
179 /* https://bugs.freedesktop.org/show_bug.cgi?id=81515 */
180 .callback
= video_detect_force_video
,
181 .ident
= "HP ENVY 15 Notebook",
183 DMI_MATCH(DMI_SYS_VENDOR
, "Hewlett-Packard"),
184 DMI_MATCH(DMI_PRODUCT_NAME
, "HP ENVY 15 Notebook PC"),
188 .callback
= video_detect_force_video
,
189 .ident
= "SAMSUNG 870Z5E/880Z5E/680Z5E",
191 DMI_MATCH(DMI_SYS_VENDOR
, "SAMSUNG ELECTRONICS CO., LTD."),
192 DMI_MATCH(DMI_PRODUCT_NAME
, "870Z5E/880Z5E/680Z5E"),
196 .callback
= video_detect_force_video
,
197 .ident
= "SAMSUNG 370R4E/370R4V/370R5E/3570RE/370R5V",
199 DMI_MATCH(DMI_SYS_VENDOR
, "SAMSUNG ELECTRONICS CO., LTD."),
200 DMI_MATCH(DMI_PRODUCT_NAME
,
201 "370R4E/370R4V/370R5E/3570RE/370R5V"),
205 /* https://bugzilla.redhat.com/show_bug.cgi?id=1186097 */
206 .callback
= video_detect_force_video
,
207 .ident
= "SAMSUNG 3570R/370R/470R/450R/510R/4450RV",
209 DMI_MATCH(DMI_SYS_VENDOR
, "SAMSUNG ELECTRONICS CO., LTD."),
210 DMI_MATCH(DMI_PRODUCT_NAME
,
211 "3570R/370R/470R/450R/510R/4450RV"),
215 /* https://bugzilla.redhat.com/show_bug.cgi?id=1094948 */
216 .callback
= video_detect_force_video
,
217 .ident
= "SAMSUNG 730U3E/740U3E",
219 DMI_MATCH(DMI_SYS_VENDOR
, "SAMSUNG ELECTRONICS CO., LTD."),
220 DMI_MATCH(DMI_PRODUCT_NAME
, "730U3E/740U3E"),
224 /* https://bugs.freedesktop.org/show_bug.cgi?id=87286 */
225 .callback
= video_detect_force_video
,
226 .ident
= "SAMSUNG 900X3C/900X3D/900X3E/900X4C/900X4D",
228 DMI_MATCH(DMI_SYS_VENDOR
, "SAMSUNG ELECTRONICS CO., LTD."),
229 DMI_MATCH(DMI_PRODUCT_NAME
,
230 "900X3C/900X3D/900X3E/900X4C/900X4D"),
234 /* https://bugzilla.redhat.com/show_bug.cgi?id=1163574 */
235 .callback
= video_detect_force_video
,
236 .ident
= "Dell XPS15 L521X",
238 DMI_MATCH(DMI_SYS_VENDOR
, "Dell Inc."),
239 DMI_MATCH(DMI_PRODUCT_NAME
, "XPS L521X"),
243 /* Non win8 machines which need native backlight nevertheless */
245 /* https://bugzilla.redhat.com/show_bug.cgi?id=1187004 */
246 .callback
= video_detect_force_native
,
247 .ident
= "Lenovo Ideapad Z570",
249 DMI_MATCH(DMI_SYS_VENDOR
, "LENOVO"),
250 DMI_MATCH(DMI_PRODUCT_NAME
, "102434U"),
254 /* https://bugzilla.redhat.com/show_bug.cgi?id=1217249 */
255 .callback
= video_detect_force_native
,
256 .ident
= "Apple MacBook Pro 12,1",
258 DMI_MATCH(DMI_SYS_VENDOR
, "Apple Inc."),
259 DMI_MATCH(DMI_PRODUCT_NAME
, "MacBookPro12,1"),
265 static int acpi_video_backlight_notify(struct notifier_block
*nb
,
266 unsigned long val
, void *bd
)
268 struct backlight_device
*backlight
= bd
;
270 /* A raw bl registering may change video -> native */
271 if (backlight
->props
.type
== BACKLIGHT_RAW
&&
272 val
== BACKLIGHT_REGISTERED
&&
273 acpi_video_get_backlight_type() != acpi_backlight_video
)
274 acpi_video_unregister_backlight();
280 * Determine which type of backlight interface to use on this system,
281 * First check cmdline, then dmi quirks, then do autodetect.
283 * The autodetect order is:
284 * 1) Is the acpi-video backlight interface supported ->
285 * no, use a vendor interface
286 * 2) Is this a win8 "ready" BIOS and do we have a native interface ->
287 * yes, use a native interface
288 * 3) Else use the acpi-video interface
290 * Arguably the native on win8 check should be done first, but that would
291 * be a behavior change, which may causes issues.
293 enum acpi_backlight_type
acpi_video_get_backlight_type(void)
295 static DEFINE_MUTEX(init_mutex
);
296 static bool init_done
;
297 static long video_caps
;
299 /* Parse cmdline, dmi and acpi only once */
300 mutex_lock(&init_mutex
);
302 acpi_video_parse_cmdline();
303 dmi_check_system(video_detect_dmi_table
);
304 acpi_walk_namespace(ACPI_TYPE_DEVICE
, ACPI_ROOT_OBJECT
,
305 ACPI_UINT32_MAX
, find_video
, NULL
,
307 backlight_nb
.notifier_call
= acpi_video_backlight_notify
;
308 backlight_nb
.priority
= 0;
309 if (backlight_register_notifier(&backlight_nb
) == 0)
310 backlight_notifier_registered
= true;
313 mutex_unlock(&init_mutex
);
315 if (acpi_backlight_cmdline
!= acpi_backlight_undef
)
316 return acpi_backlight_cmdline
;
318 if (acpi_backlight_dmi
!= acpi_backlight_undef
)
319 return acpi_backlight_dmi
;
321 if (!(video_caps
& ACPI_VIDEO_BACKLIGHT
))
322 return acpi_backlight_vendor
;
324 if (acpi_osi_is_win8() && backlight_device_registered(BACKLIGHT_RAW
))
325 return acpi_backlight_native
;
327 return acpi_backlight_video
;
329 EXPORT_SYMBOL(acpi_video_get_backlight_type
);
332 * Set the preferred backlight interface type based on DMI info.
333 * This function allows DMI blacklists to be implemented by external
334 * platform drivers instead of putting a big blacklist in video_detect.c
336 void acpi_video_set_dmi_backlight_type(enum acpi_backlight_type type
)
338 acpi_backlight_dmi
= type
;
339 /* Remove acpi-video backlight interface if it is no longer desired */
340 if (acpi_video_get_backlight_type() != acpi_backlight_video
)
341 acpi_video_unregister_backlight();
343 EXPORT_SYMBOL(acpi_video_set_dmi_backlight_type
);
345 void __exit
acpi_video_detect_exit(void)
347 if (backlight_notifier_registered
)
348 backlight_unregister_notifier(&backlight_nb
);