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);