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 int video_detect_force_none(const struct dmi_system_id *d)
107{
108 acpi_backlight_dmi = acpi_backlight_none;
109 return 0;
110}
111
112static 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().
118 */
119 {
120 .callback = video_detect_force_vendor,
121 .ident = "X360",
122 .matches = {
123 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
124 DMI_MATCH(DMI_PRODUCT_NAME, "X360"),
125 DMI_MATCH(DMI_BOARD_NAME, "X360"),
126 },
127 },
128 {
129 .callback = video_detect_force_vendor,
130 .ident = "Asus UL30VT",
131 .matches = {
132 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
133 DMI_MATCH(DMI_PRODUCT_NAME, "UL30VT"),
134 },
135 },
136 {
137 .callback = video_detect_force_vendor,
138 .ident = "Asus UL30A",
139 .matches = {
140 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK Computer Inc."),
141 DMI_MATCH(DMI_PRODUCT_NAME, "UL30A"),
142 },
143 },
144
145 /*
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
151 */
152 {
153 .callback = video_detect_force_video,
154 .ident = "ThinkPad T420",
155 .matches = {
156 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
157 DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T420"),
158 },
159 },
160 {
161 .callback = video_detect_force_video,
162 .ident = "ThinkPad T520",
163 .matches = {
164 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
165 DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T520"),
166 },
167 },
168 {
169 .callback = video_detect_force_video,
170 .ident = "ThinkPad X201s",
171 .matches = {
172 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
173 DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X201s"),
174 },
175 },
176 {
177 .callback = video_detect_force_video,
178 .ident = "ThinkPad X201T",
179 .matches = {
180 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
181 DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad X201T"),
182 },
183 },
184
185 /* The native backlight controls do not work on some older machines */
186 {
187 /* https://bugs.freedesktop.org/show_bug.cgi?id=81515 */
188 .callback = video_detect_force_video,
189 .ident = "HP ENVY 15 Notebook",
190 .matches = {
191 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
192 DMI_MATCH(DMI_PRODUCT_NAME, "HP ENVY 15 Notebook PC"),
193 },
194 },
195 {
196 .callback = video_detect_force_video,
197 .ident = "SAMSUNG 870Z5E/880Z5E/680Z5E",
198 .matches = {
199 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
200 DMI_MATCH(DMI_PRODUCT_NAME, "870Z5E/880Z5E/680Z5E"),
201 },
202 },
203 {
204 .callback = video_detect_force_video,
205 .ident = "SAMSUNG 370R4E/370R4V/370R5E/3570RE/370R5V",
206 .matches = {
207 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
208 DMI_MATCH(DMI_PRODUCT_NAME,
209 "370R4E/370R4V/370R5E/3570RE/370R5V"),
210 },
211 },
212 {
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",
216 .matches = {
217 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
218 DMI_MATCH(DMI_PRODUCT_NAME,
219 "3570R/370R/470R/450R/510R/4450RV"),
220 },
221 },
222 {
223 /* https://bugzilla.redhat.com/show_bug.cgi?id=1557060 */
224 .callback = video_detect_force_video,
225 .ident = "SAMSUNG 670Z5E",
226 .matches = {
227 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
228 DMI_MATCH(DMI_PRODUCT_NAME, "670Z5E"),
229 },
230 },
231 {
232 /* https://bugzilla.redhat.com/show_bug.cgi?id=1094948 */
233 .callback = video_detect_force_video,
234 .ident = "SAMSUNG 730U3E/740U3E",
235 .matches = {
236 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
237 DMI_MATCH(DMI_PRODUCT_NAME, "730U3E/740U3E"),
238 },
239 },
240 {
241 /* https://bugs.freedesktop.org/show_bug.cgi?id=87286 */
242 .callback = video_detect_force_video,
243 .ident = "SAMSUNG 900X3C/900X3D/900X3E/900X4C/900X4D",
244 .matches = {
245 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
246 DMI_MATCH(DMI_PRODUCT_NAME,
247 "900X3C/900X3D/900X3E/900X4C/900X4D"),
248 },
249 },
250 {
251 /* https://bugzilla.redhat.com/show_bug.cgi?id=1272633 */
252 .callback = video_detect_force_video,
253 .ident = "Dell XPS14 L421X",
254 .matches = {
255 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
256 DMI_MATCH(DMI_PRODUCT_NAME, "XPS L421X"),
257 },
258 },
259 {
260 /* https://bugzilla.redhat.com/show_bug.cgi?id=1163574 */
261 .callback = video_detect_force_video,
262 .ident = "Dell XPS15 L521X",
263 .matches = {
264 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
265 DMI_MATCH(DMI_PRODUCT_NAME, "XPS L521X"),
266 },
267 },
268 {
269 /* https://bugzilla.kernel.org/show_bug.cgi?id=108971 */
270 .callback = video_detect_force_video,
271 .ident = "SAMSUNG 530U4E/540U4E",
272 .matches = {
273 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
274 DMI_MATCH(DMI_PRODUCT_NAME, "530U4E/540U4E"),
275 },
276 },
277
278 /* Non win8 machines which need native backlight nevertheless */
279 {
280 /* https://bugzilla.redhat.com/show_bug.cgi?id=1201530 */
281 .callback = video_detect_force_native,
282 .ident = "Lenovo Ideapad S405",
283 .matches = {
284 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
285 DMI_MATCH(DMI_BOARD_NAME, "Lenovo IdeaPad S405"),
286 },
287 },
288 {
289 /* https://bugzilla.redhat.com/show_bug.cgi?id=1187004 */
290 .callback = video_detect_force_native,
291 .ident = "Lenovo Ideapad Z570",
292 .matches = {
293 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
294 DMI_MATCH(DMI_PRODUCT_NAME, "102434U"),
295 },
296 },
297 {
298 /* https://bugzilla.redhat.com/show_bug.cgi?id=1217249 */
299 .callback = video_detect_force_native,
300 .ident = "Apple MacBook Pro 12,1",
301 .matches = {
302 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
303 DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro12,1"),
304 },
305 },
306 {
307 .callback = video_detect_force_native,
308 .ident = "Dell Vostro V131",
309 .matches = {
310 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
311 DMI_MATCH(DMI_PRODUCT_NAME, "Vostro V131"),
312 },
313 },
314 {
315 /* https://bugzilla.redhat.com/show_bug.cgi?id=1123661 */
316 .callback = video_detect_force_native,
317 .ident = "Dell XPS 17 L702X",
318 .matches = {
319 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
320 DMI_MATCH(DMI_PRODUCT_NAME, "Dell System XPS L702X"),
321 },
322 },
323 {
324 .callback = video_detect_force_native,
325 .ident = "Dell Precision 7510",
326 .matches = {
327 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
328 DMI_MATCH(DMI_PRODUCT_NAME, "Precision 7510"),
329 },
330 },
331 {
332 .callback = video_detect_force_none,
333 .ident = "Dell OptiPlex 9020M",
334 .matches = {
335 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
336 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 9020M"),
337 },
338 },
339 { },
340};
341
342/* This uses a workqueue to avoid various locking ordering issues */
343static void acpi_video_backlight_notify_work(struct work_struct *work)
344{
345 if (acpi_video_get_backlight_type() != acpi_backlight_video)
346 acpi_video_unregister_backlight();
347}
348
349static int acpi_video_backlight_notify(struct notifier_block *nb,
350 unsigned long val, void *bd)
351{
352 struct backlight_device *backlight = bd;
353
354 /* A raw bl registering may change video -> native */
355 if (backlight->props.type == BACKLIGHT_RAW &&
356 val == BACKLIGHT_REGISTERED)
357 schedule_work(&backlight_notify_work);
358
359 return NOTIFY_OK;
360}
361
362/*
363 * Determine which type of backlight interface to use on this system,
364 * First check cmdline, then dmi quirks, then do autodetect.
365 *
366 * The autodetect order is:
367 * 1) Is the acpi-video backlight interface supported ->
368 * no, use a vendor interface
369 * 2) Is this a win8 "ready" BIOS and do we have a native interface ->
370 * yes, use a native interface
371 * 3) Else use the acpi-video interface
372 *
373 * Arguably the native on win8 check should be done first, but that would
374 * be a behavior change, which may causes issues.
375 */
376enum acpi_backlight_type acpi_video_get_backlight_type(void)
377{
378 static DEFINE_MUTEX(init_mutex);
379 static bool init_done;
380 static long video_caps;
381
382 /* Parse cmdline, dmi and acpi only once */
383 mutex_lock(&init_mutex);
384 if (!init_done) {
385 acpi_video_parse_cmdline();
386 dmi_check_system(video_detect_dmi_table);
387 acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
388 ACPI_UINT32_MAX, find_video, NULL,
389 &video_caps, NULL);
390 INIT_WORK(&backlight_notify_work,
391 acpi_video_backlight_notify_work);
392 backlight_nb.notifier_call = acpi_video_backlight_notify;
393 backlight_nb.priority = 0;
394 if (backlight_register_notifier(&backlight_nb) == 0)
395 backlight_notifier_registered = true;
396 init_done = true;
397 }
398 mutex_unlock(&init_mutex);
399
400 if (acpi_backlight_cmdline != acpi_backlight_undef)
401 return acpi_backlight_cmdline;
402
403 if (acpi_backlight_dmi != acpi_backlight_undef)
404 return acpi_backlight_dmi;
405
406 if (!(video_caps & ACPI_VIDEO_BACKLIGHT))
407 return acpi_backlight_vendor;
408
409 if (acpi_osi_is_win8() && backlight_device_get_by_type(BACKLIGHT_RAW))
410 return acpi_backlight_native;
411
412 return acpi_backlight_video;
413}
414EXPORT_SYMBOL(acpi_video_get_backlight_type);
415
416/*
417 * Set the preferred backlight interface type based on DMI info.
418 * This function allows DMI blacklists to be implemented by external
419 * platform drivers instead of putting a big blacklist in video_detect.c
420 */
421void acpi_video_set_dmi_backlight_type(enum acpi_backlight_type type)
422{
423 acpi_backlight_dmi = type;
424 /* Remove acpi-video backlight interface if it is no longer desired */
425 if (acpi_video_get_backlight_type() != acpi_backlight_video)
426 acpi_video_unregister_backlight();
427}
428EXPORT_SYMBOL(acpi_video_set_dmi_backlight_type);
429
430void __exit acpi_video_detect_exit(void)
431{
432 if (backlight_notifier_registered)
433 backlight_unregister_notifier(&backlight_nb);
434}
435