1 /*
2 * Dell WMI hotkeys
3 *
4 * Copyright (C) 2008 Red Hat <mjg@redhat.com>
5 * Copyright (C) 2014-2015 Pali Rohár <pali.rohar@gmail.com>
6 *
7 * Portions based on wistron_btns.c:
8 * Copyright (C) 2005 Miloslav Trmac <mitr@volny.cz>
9 * Copyright (C) 2005 Bernhard Rosenkraenzer <bero@arklinux.org>
10 * Copyright (C) 2005 Dmitry Torokhov <dtor@mail.ru>
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or
15 * (at your option) any later version.
16 *
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
21 *
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
25 */
26
27 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
28
29 #include <linux/kernel.h>
30 #include <linux/module.h>
31 #include <linux/init.h>
32 #include <linux/slab.h>
33 #include <linux/types.h>
34 #include <linux/input.h>
35 #include <linux/input/sparse-keymap.h>
36 #include <linux/acpi.h>
37 #include <linux/string.h>
38 #include <linux/dmi.h>
39 #include <linux/wmi.h>
40 #include <acpi/video.h>
41 #include "dell-smbios.h"
42
43 MODULE_AUTHOR("Matthew Garrett <mjg@redhat.com>");
44 MODULE_AUTHOR("Pali Rohár <pali.rohar@gmail.com>");
45 MODULE_DESCRIPTION("Dell laptop WMI hotkeys driver");
46 MODULE_LICENSE("GPL");
47
48 #define DELL_EVENT_GUID "9DBB5994-A997-11DA-B012-B622A1EF5492"
49 #define DELL_DESCRIPTOR_GUID "8D9DDCBC-A997-11DA-B012-B622A1EF5492"
50
51 static bool wmi_requires_smbios_request;
52
53 MODULE_ALIAS("wmi:"DELL_EVENT_GUID);
54 MODULE_ALIAS("wmi:"DELL_DESCRIPTOR_GUID);
55
56 struct dell_wmi_priv {
57 struct input_dev *input_dev;
58 u32 interface_version;
59 };
60
dmi_matched(const struct dmi_system_id * dmi)61 static int __init dmi_matched(const struct dmi_system_id *dmi)
62 {
63 wmi_requires_smbios_request = 1;
64 return 1;
65 }
66
67 static const struct dmi_system_id dell_wmi_smbios_list[] __initconst = {
68 {
69 .callback = dmi_matched,
70 .ident = "Dell Inspiron M5110",
71 .matches = {
72 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
73 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron M5110"),
74 },
75 },
76 {
77 .callback = dmi_matched,
78 .ident = "Dell Vostro V131",
79 .matches = {
80 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
81 DMI_MATCH(DMI_PRODUCT_NAME, "Vostro V131"),
82 },
83 },
84 { }
85 };
86
87 /*
88 * Keymap for WMI events of type 0x0000
89 *
90 * Certain keys are flagged as KE_IGNORE. All of these are either
91 * notifications (rather than requests for change) or are also sent
92 * via the keyboard controller so should not be sent again.
93 */
94 static const struct key_entry dell_wmi_keymap_type_0000[] = {
95 { KE_IGNORE, 0x003a, { KEY_CAPSLOCK } },
96
97 /* Key code is followed by brightness level */
98 { KE_KEY, 0xe005, { KEY_BRIGHTNESSDOWN } },
99 { KE_KEY, 0xe006, { KEY_BRIGHTNESSUP } },
100
101 /* Battery health status button */
102 { KE_KEY, 0xe007, { KEY_BATTERY } },
103
104 /* Radio devices state change, key code is followed by other values */
105 { KE_IGNORE, 0xe008, { KEY_RFKILL } },
106
107 { KE_KEY, 0xe009, { KEY_EJECTCD } },
108
109 /* Key code is followed by: next, active and attached devices */
110 { KE_KEY, 0xe00b, { KEY_SWITCHVIDEOMODE } },
111
112 /* Key code is followed by keyboard illumination level */
113 { KE_IGNORE, 0xe00c, { KEY_KBDILLUMTOGGLE } },
114
115 /* BIOS error detected */
116 { KE_IGNORE, 0xe00d, { KEY_RESERVED } },
117
118 /* Battery was removed or inserted */
119 { KE_IGNORE, 0xe00e, { KEY_RESERVED } },
120
121 /* Wifi Catcher */
122 { KE_KEY, 0xe011, { KEY_WLAN } },
123
124 /* Ambient light sensor toggle */
125 { KE_IGNORE, 0xe013, { KEY_RESERVED } },
126
127 { KE_IGNORE, 0xe020, { KEY_MUTE } },
128
129 /* Unknown, defined in ACPI DSDT */
130 /* { KE_IGNORE, 0xe023, { KEY_RESERVED } }, */
131
132 /* Untested, Dell Instant Launch key on Inspiron 7520 */
133 /* { KE_IGNORE, 0xe024, { KEY_RESERVED } }, */
134
135 /* Dell Instant Launch key */
136 { KE_KEY, 0xe025, { KEY_PROG4 } },
137
138 /* Audio panel key */
139 { KE_IGNORE, 0xe026, { KEY_RESERVED } },
140
141 /* LCD Display On/Off Control key */
142 { KE_KEY, 0xe027, { KEY_DISPLAYTOGGLE } },
143
144 /* Untested, Multimedia key on Dell Vostro 3560 */
145 /* { KE_IGNORE, 0xe028, { KEY_RESERVED } }, */
146
147 /* Dell Instant Launch key */
148 { KE_KEY, 0xe029, { KEY_PROG4 } },
149
150 /* Untested, Windows Mobility Center button on Inspiron 7520 */
151 /* { KE_IGNORE, 0xe02a, { KEY_RESERVED } }, */
152
153 /* Unknown, defined in ACPI DSDT */
154 /* { KE_IGNORE, 0xe02b, { KEY_RESERVED } }, */
155
156 /* Untested, Dell Audio With Preset Switch button on Inspiron 7520 */
157 /* { KE_IGNORE, 0xe02c, { KEY_RESERVED } }, */
158
159 { KE_IGNORE, 0xe02e, { KEY_VOLUMEDOWN } },
160 { KE_IGNORE, 0xe030, { KEY_VOLUMEUP } },
161 { KE_IGNORE, 0xe033, { KEY_KBDILLUMUP } },
162 { KE_IGNORE, 0xe034, { KEY_KBDILLUMDOWN } },
163 { KE_IGNORE, 0xe03a, { KEY_CAPSLOCK } },
164
165 /* NIC Link is Up */
166 { KE_IGNORE, 0xe043, { KEY_RESERVED } },
167
168 /* NIC Link is Down */
169 { KE_IGNORE, 0xe044, { KEY_RESERVED } },
170
171 /*
172 * This entry is very suspicious!
173 * Originally Matthew Garrett created this dell-wmi driver specially for
174 * "button with a picture of a battery" which has event code 0xe045.
175 * Later Mario Limonciello from Dell told us that event code 0xe045 is
176 * reported by Num Lock and should be ignored because key is send also
177 * by keyboard controller.
178 * So for now we will ignore this event to prevent potential double
179 * Num Lock key press.
180 */
181 { KE_IGNORE, 0xe045, { KEY_NUMLOCK } },
182
183 /* Scroll lock and also going to tablet mode on portable devices */
184 { KE_IGNORE, 0xe046, { KEY_SCROLLLOCK } },
185
186 /* Untested, going from tablet mode on portable devices */
187 /* { KE_IGNORE, 0xe047, { KEY_RESERVED } }, */
188
189 /* Dell Support Center key */
190 { KE_IGNORE, 0xe06e, { KEY_RESERVED } },
191
192 { KE_IGNORE, 0xe0f7, { KEY_MUTE } },
193 { KE_IGNORE, 0xe0f8, { KEY_VOLUMEDOWN } },
194 { KE_IGNORE, 0xe0f9, { KEY_VOLUMEUP } },
195 };
196
197 struct dell_bios_keymap_entry {
198 u16 scancode;
199 u16 keycode;
200 };
201
202 struct dell_bios_hotkey_table {
203 struct dmi_header header;
204 struct dell_bios_keymap_entry keymap[];
205
206 };
207
208 struct dell_dmi_results {
209 int err;
210 int keymap_size;
211 struct key_entry *keymap;
212 };
213
214 /* Uninitialized entries here are KEY_RESERVED == 0. */
215 static const u16 bios_to_linux_keycode[256] = {
216 [0] = KEY_MEDIA,
217 [1] = KEY_NEXTSONG,
218 [2] = KEY_PLAYPAUSE,
219 [3] = KEY_PREVIOUSSONG,
220 [4] = KEY_STOPCD,
221 [5] = KEY_UNKNOWN,
222 [6] = KEY_UNKNOWN,
223 [7] = KEY_UNKNOWN,
224 [8] = KEY_WWW,
225 [9] = KEY_UNKNOWN,
226 [10] = KEY_VOLUMEDOWN,
227 [11] = KEY_MUTE,
228 [12] = KEY_VOLUMEUP,
229 [13] = KEY_UNKNOWN,
230 [14] = KEY_BATTERY,
231 [15] = KEY_EJECTCD,
232 [16] = KEY_UNKNOWN,
233 [17] = KEY_SLEEP,
234 [18] = KEY_PROG1,
235 [19] = KEY_BRIGHTNESSDOWN,
236 [20] = KEY_BRIGHTNESSUP,
237 [21] = KEY_UNKNOWN,
238 [22] = KEY_KBDILLUMTOGGLE,
239 [23] = KEY_UNKNOWN,
240 [24] = KEY_SWITCHVIDEOMODE,
241 [25] = KEY_UNKNOWN,
242 [26] = KEY_UNKNOWN,
243 [27] = KEY_SWITCHVIDEOMODE,
244 [28] = KEY_UNKNOWN,
245 [29] = KEY_UNKNOWN,
246 [30] = KEY_PROG2,
247 [31] = KEY_UNKNOWN,
248 [32] = KEY_UNKNOWN,
249 [33] = KEY_UNKNOWN,
250 [34] = KEY_UNKNOWN,
251 [35] = KEY_UNKNOWN,
252 [36] = KEY_UNKNOWN,
253 [37] = KEY_UNKNOWN,
254 [38] = KEY_MICMUTE,
255 [255] = KEY_PROG3,
256 };
257
258 /*
259 * Keymap for WMI events of type 0x0010
260 *
261 * These are applied if the 0xB2 DMI hotkey table is present and doesn't
262 * override them.
263 */
264 static const struct key_entry dell_wmi_keymap_type_0010[] = {
265 /* Fn-lock */
266 { KE_IGNORE, 0x151, { KEY_RESERVED } },
267
268 /* Change keyboard illumination */
269 { KE_IGNORE, 0x152, { KEY_KBDILLUMTOGGLE } },
270
271 /*
272 * Radio disable (notify only -- there is no model for which the
273 * WMI event is supposed to trigger an action).
274 */
275 { KE_IGNORE, 0x153, { KEY_RFKILL } },
276
277 /* RGB keyboard backlight control */
278 { KE_IGNORE, 0x154, { KEY_RESERVED } },
279
280 /*
281 * Stealth mode toggle. This will "disable all lights and sounds".
282 * The action is performed by the BIOS and EC; the WMI event is just
283 * a notification. On the XPS 13 9350, this is Fn+F7, and there's
284 * a BIOS setting to enable and disable the hotkey.
285 */
286 { KE_IGNORE, 0x155, { KEY_RESERVED } },
287
288 /* Rugged magnetic dock attach/detach events */
289 { KE_IGNORE, 0x156, { KEY_RESERVED } },
290 { KE_IGNORE, 0x157, { KEY_RESERVED } },
291
292 /* Rugged programmable (P1/P2/P3 keys) */
293 { KE_KEY, 0x850, { KEY_PROG1 } },
294 { KE_KEY, 0x851, { KEY_PROG2 } },
295 { KE_KEY, 0x852, { KEY_PROG3 } },
296
297 };
298
299 /*
300 * Keymap for WMI events of type 0x0011
301 */
302 static const struct key_entry dell_wmi_keymap_type_0011[] = {
303 /* Battery unplugged */
304 { KE_IGNORE, 0xfff0, { KEY_RESERVED } },
305
306 /* Battery inserted */
307 { KE_IGNORE, 0xfff1, { KEY_RESERVED } },
308
309 /* Keyboard backlight level changed */
310 { KE_IGNORE, 0x01e1, { KEY_RESERVED } },
311 { KE_IGNORE, 0x02ea, { KEY_RESERVED } },
312 { KE_IGNORE, 0x02eb, { KEY_RESERVED } },
313 { KE_IGNORE, 0x02ec, { KEY_RESERVED } },
314 { KE_IGNORE, 0x02f6, { KEY_RESERVED } },
315 };
316
dell_wmi_process_key(struct wmi_device * wdev,int type,int code)317 static void dell_wmi_process_key(struct wmi_device *wdev, int type, int code)
318 {
319 struct dell_wmi_priv *priv = dev_get_drvdata(&wdev->dev);
320 const struct key_entry *key;
321
322 key = sparse_keymap_entry_from_scancode(priv->input_dev,
323 (type << 16) | code);
324 if (!key) {
325 pr_info("Unknown key with type 0x%04x and code 0x%04x pressed\n",
326 type, code);
327 return;
328 }
329
330 pr_debug("Key with type 0x%04x and code 0x%04x pressed\n", type, code);
331
332 /* Don't report brightness notifications that will also come via ACPI */
333 if ((key->keycode == KEY_BRIGHTNESSUP ||
334 key->keycode == KEY_BRIGHTNESSDOWN) &&
335 acpi_video_handles_brightness_key_presses())
336 return;
337
338 if (type == 0x0000 && code == 0xe025 && !wmi_requires_smbios_request)
339 return;
340
341 if (key->keycode == KEY_KBDILLUMTOGGLE)
342 dell_laptop_call_notifier(
343 DELL_LAPTOP_KBD_BACKLIGHT_BRIGHTNESS_CHANGED, NULL);
344
345 sparse_keymap_report_entry(priv->input_dev, key, 1, true);
346 }
347
dell_wmi_notify(struct wmi_device * wdev,union acpi_object * obj)348 static void dell_wmi_notify(struct wmi_device *wdev,
349 union acpi_object *obj)
350 {
351 struct dell_wmi_priv *priv = dev_get_drvdata(&wdev->dev);
352 u16 *buffer_entry, *buffer_end;
353 acpi_size buffer_size;
354 int len, i;
355
356 if (obj->type != ACPI_TYPE_BUFFER) {
357 pr_warn("bad response type %x\n", obj->type);
358 return;
359 }
360
361 pr_debug("Received WMI event (%*ph)\n",
362 obj->buffer.length, obj->buffer.pointer);
363
364 buffer_entry = (u16 *)obj->buffer.pointer;
365 buffer_size = obj->buffer.length/2;
366 buffer_end = buffer_entry + buffer_size;
367
368 /*
369 * BIOS/ACPI on devices with WMI interface version 0 does not clear
370 * buffer before filling it. So next time when BIOS/ACPI send WMI event
371 * which is smaller as previous then it contains garbage in buffer from
372 * previous event.
373 *
374 * BIOS/ACPI on devices with WMI interface version 1 clears buffer and
375 * sometimes send more events in buffer at one call.
376 *
377 * So to prevent reading garbage from buffer we will process only first
378 * one event on devices with WMI interface version 0.
379 */
380 if (priv->interface_version == 0 && buffer_entry < buffer_end)
381 if (buffer_end > buffer_entry + buffer_entry[0] + 1)
382 buffer_end = buffer_entry + buffer_entry[0] + 1;
383
384 while (buffer_entry < buffer_end) {
385
386 len = buffer_entry[0];
387 if (len == 0)
388 break;
389
390 len++;
391
392 if (buffer_entry + len > buffer_end) {
393 pr_warn("Invalid length of WMI event\n");
394 break;
395 }
396
397 pr_debug("Process buffer (%*ph)\n", len*2, buffer_entry);
398
399 switch (buffer_entry[1]) {
400 case 0x0000: /* One key pressed or event occurred */
401 if (len > 2)
402 dell_wmi_process_key(wdev, 0x0000,
403 buffer_entry[2]);
404 /* Other entries could contain additional information */
405 break;
406 case 0x0010: /* Sequence of keys pressed */
407 case 0x0011: /* Sequence of events occurred */
408 for (i = 2; i < len; ++i)
409 dell_wmi_process_key(wdev, buffer_entry[1],
410 buffer_entry[i]);
411 break;
412 default: /* Unknown event */
413 pr_info("Unknown WMI event type 0x%x\n",
414 (int)buffer_entry[1]);
415 break;
416 }
417
418 buffer_entry += len;
419
420 }
421
422 }
423
have_scancode(u32 scancode,const struct key_entry * keymap,int len)424 static bool have_scancode(u32 scancode, const struct key_entry *keymap, int len)
425 {
426 int i;
427
428 for (i = 0; i < len; i++)
429 if (keymap[i].code == scancode)
430 return true;
431
432 return false;
433 }
434
handle_dmi_entry(const struct dmi_header * dm,void * opaque)435 static void handle_dmi_entry(const struct dmi_header *dm, void *opaque)
436 {
437 struct dell_dmi_results *results = opaque;
438 struct dell_bios_hotkey_table *table;
439 int hotkey_num, i, pos = 0;
440 struct key_entry *keymap;
441
442 if (results->err || results->keymap)
443 return; /* We already found the hotkey table. */
444
445 /* The Dell hotkey table is type 0xB2. Scan until we find it. */
446 if (dm->type != 0xb2)
447 return;
448
449 table = container_of(dm, struct dell_bios_hotkey_table, header);
450
451 hotkey_num = (table->header.length -
452 sizeof(struct dell_bios_hotkey_table)) /
453 sizeof(struct dell_bios_keymap_entry);
454 if (hotkey_num < 1) {
455 /*
456 * Historically, dell-wmi would ignore a DMI entry of
457 * fewer than 7 bytes. Sizes between 4 and 8 bytes are
458 * nonsensical (both the header and all entries are 4
459 * bytes), so we approximate the old behavior by
460 * ignoring tables with fewer than one entry.
461 */
462 return;
463 }
464
465 keymap = kcalloc(hotkey_num, sizeof(struct key_entry), GFP_KERNEL);
466 if (!keymap) {
467 results->err = -ENOMEM;
468 return;
469 }
470
471 for (i = 0; i < hotkey_num; i++) {
472 const struct dell_bios_keymap_entry *bios_entry =
473 &table->keymap[i];
474
475 /* Uninitialized entries are 0 aka KEY_RESERVED. */
476 u16 keycode = (bios_entry->keycode <
477 ARRAY_SIZE(bios_to_linux_keycode)) ?
478 bios_to_linux_keycode[bios_entry->keycode] :
479 KEY_RESERVED;
480
481 /*
482 * Log if we find an entry in the DMI table that we don't
483 * understand. If this happens, we should figure out what
484 * the entry means and add it to bios_to_linux_keycode.
485 */
486 if (keycode == KEY_RESERVED) {
487 pr_info("firmware scancode 0x%x maps to unrecognized keycode 0x%x\n",
488 bios_entry->scancode, bios_entry->keycode);
489 continue;
490 }
491
492 if (keycode == KEY_KBDILLUMTOGGLE)
493 keymap[pos].type = KE_IGNORE;
494 else
495 keymap[pos].type = KE_KEY;
496 keymap[pos].code = bios_entry->scancode;
497 keymap[pos].keycode = keycode;
498
499 pos++;
500 }
501
502 results->keymap = keymap;
503 results->keymap_size = pos;
504 }
505
dell_wmi_input_setup(struct wmi_device * wdev)506 static int dell_wmi_input_setup(struct wmi_device *wdev)
507 {
508 struct dell_wmi_priv *priv = dev_get_drvdata(&wdev->dev);
509 struct dell_dmi_results dmi_results = {};
510 struct key_entry *keymap;
511 int err, i, pos = 0;
512
513 priv->input_dev = input_allocate_device();
514 if (!priv->input_dev)
515 return -ENOMEM;
516
517 priv->input_dev->name = "Dell WMI hotkeys";
518 priv->input_dev->id.bustype = BUS_HOST;
519 priv->input_dev->dev.parent = &wdev->dev;
520
521 if (dmi_walk(handle_dmi_entry, &dmi_results)) {
522 /*
523 * Historically, dell-wmi ignored dmi_walk errors. A failure
524 * is certainly surprising, but it probably just indicates
525 * a very old laptop.
526 */
527 pr_warn("no DMI; using the old-style hotkey interface\n");
528 }
529
530 if (dmi_results.err) {
531 err = dmi_results.err;
532 goto err_free_dev;
533 }
534
535 keymap = kcalloc(dmi_results.keymap_size +
536 ARRAY_SIZE(dell_wmi_keymap_type_0000) +
537 ARRAY_SIZE(dell_wmi_keymap_type_0010) +
538 ARRAY_SIZE(dell_wmi_keymap_type_0011) +
539 1,
540 sizeof(struct key_entry), GFP_KERNEL);
541 if (!keymap) {
542 kfree(dmi_results.keymap);
543 err = -ENOMEM;
544 goto err_free_dev;
545 }
546
547 /* Append table with events of type 0x0010 which comes from DMI */
548 for (i = 0; i < dmi_results.keymap_size; i++) {
549 keymap[pos] = dmi_results.keymap[i];
550 keymap[pos].code |= (0x0010 << 16);
551 pos++;
552 }
553
554 kfree(dmi_results.keymap);
555
556 /* Append table with extra events of type 0x0010 which are not in DMI */
557 for (i = 0; i < ARRAY_SIZE(dell_wmi_keymap_type_0010); i++) {
558 const struct key_entry *entry = &dell_wmi_keymap_type_0010[i];
559
560 /*
561 * Check if we've already found this scancode. This takes
562 * quadratic time, but it doesn't matter unless the list
563 * of extra keys gets very long.
564 */
565 if (dmi_results.keymap_size &&
566 have_scancode(entry->code | (0x0010 << 16),
567 keymap, dmi_results.keymap_size)
568 )
569 continue;
570
571 keymap[pos] = *entry;
572 keymap[pos].code |= (0x0010 << 16);
573 pos++;
574 }
575
576 /* Append table with events of type 0x0011 */
577 for (i = 0; i < ARRAY_SIZE(dell_wmi_keymap_type_0011); i++) {
578 keymap[pos] = dell_wmi_keymap_type_0011[i];
579 keymap[pos].code |= (0x0011 << 16);
580 pos++;
581 }
582
583 /*
584 * Now append also table with "legacy" events of type 0x0000. Some of
585 * them are reported also on laptops which have scancodes in DMI.
586 */
587 for (i = 0; i < ARRAY_SIZE(dell_wmi_keymap_type_0000); i++) {
588 keymap[pos] = dell_wmi_keymap_type_0000[i];
589 pos++;
590 }
591
592 keymap[pos].type = KE_END;
593
594 err = sparse_keymap_setup(priv->input_dev, keymap, NULL);
595 /*
596 * Sparse keymap library makes a copy of keymap so we don't need the
597 * original one that was allocated.
598 */
599 kfree(keymap);
600 if (err)
601 goto err_free_dev;
602
603 err = input_register_device(priv->input_dev);
604 if (err)
605 goto err_free_dev;
606
607 return 0;
608
609 err_free_dev:
610 input_free_device(priv->input_dev);
611 return err;
612 }
613
dell_wmi_input_destroy(struct wmi_device * wdev)614 static void dell_wmi_input_destroy(struct wmi_device *wdev)
615 {
616 struct dell_wmi_priv *priv = dev_get_drvdata(&wdev->dev);
617
618 input_unregister_device(priv->input_dev);
619 }
620
621 /*
622 * Descriptor buffer is 128 byte long and contains:
623 *
624 * Name Offset Length Value
625 * Vendor Signature 0 4 "DELL"
626 * Object Signature 4 4 " WMI"
627 * WMI Interface Version 8 4 <version>
628 * WMI buffer length 12 4 4096
629 */
dell_wmi_check_descriptor_buffer(struct wmi_device * wdev)630 static int dell_wmi_check_descriptor_buffer(struct wmi_device *wdev)
631 {
632 struct dell_wmi_priv *priv = dev_get_drvdata(&wdev->dev);
633 union acpi_object *obj = NULL;
634 struct wmi_device *desc_dev;
635 u32 *buffer;
636 int ret;
637
638 desc_dev = wmidev_get_other_guid(wdev, DELL_DESCRIPTOR_GUID);
639 if (!desc_dev) {
640 dev_err(&wdev->dev, "Dell WMI descriptor does not exist\n");
641 return -ENODEV;
642 }
643
644 obj = wmidev_block_query(desc_dev, 0);
645 if (!obj) {
646 dev_err(&wdev->dev, "failed to read Dell WMI descriptor\n");
647 ret = -EIO;
648 goto out;
649 }
650
651 if (obj->type != ACPI_TYPE_BUFFER) {
652 dev_err(&wdev->dev, "Dell descriptor has wrong type\n");
653 ret = -EINVAL;
654 goto out;
655 }
656
657 if (obj->buffer.length != 128) {
658 dev_err(&wdev->dev,
659 "Dell descriptor buffer has invalid length (%d)\n",
660 obj->buffer.length);
661 if (obj->buffer.length < 16) {
662 ret = -EINVAL;
663 goto out;
664 }
665 }
666
667 buffer = (u32 *)obj->buffer.pointer;
668
669 if (buffer[0] != 0x4C4C4544 && buffer[1] != 0x494D5720)
670 dev_warn(&wdev->dev, "Dell descriptor buffer has invalid signature (%*ph)\n",
671 8, buffer);
672
673 if (buffer[2] != 0 && buffer[2] != 1)
674 dev_warn(&wdev->dev, "Dell descriptor buffer has unknown version (%d)\n",
675 buffer[2]);
676
677 if (buffer[3] != 4096)
678 dev_warn(&wdev->dev, "Dell descriptor buffer has invalid buffer length (%d)\n",
679 buffer[3]);
680
681 priv->interface_version = buffer[2];
682 ret = 0;
683
684 dev_info(&wdev->dev, "Detected Dell WMI interface version %u\n",
685 priv->interface_version);
686
687 out:
688 kfree(obj);
689 put_device(&desc_dev->dev);
690 return ret;
691 }
692
693 /*
694 * According to Dell SMBIOS documentation:
695 *
696 * 17 3 Application Program Registration
697 *
698 * cbArg1 Application ID 1 = 0x00010000
699 * cbArg2 Application ID 2
700 * QUICKSET/DCP = 0x51534554 "QSET"
701 * ALS Driver = 0x416c7353 "AlsS"
702 * Latitude ON = 0x4c6f6e52 "LonR"
703 * cbArg3 Application version or revision number
704 * cbArg4 0 = Unregister application
705 * 1 = Register application
706 * cbRes1 Standard return codes (0, -1, -2)
707 */
708
dell_wmi_events_set_enabled(bool enable)709 static int dell_wmi_events_set_enabled(bool enable)
710 {
711 struct calling_interface_buffer *buffer;
712 int ret;
713
714 buffer = dell_smbios_get_buffer();
715 buffer->input[0] = 0x10000;
716 buffer->input[1] = 0x51534554;
717 buffer->input[3] = enable;
718 dell_smbios_send_request(17, 3);
719 ret = buffer->output[0];
720 dell_smbios_release_buffer();
721
722 return dell_smbios_error(ret);
723 }
724
dell_wmi_probe(struct wmi_device * wdev)725 static int dell_wmi_probe(struct wmi_device *wdev)
726 {
727 struct dell_wmi_priv *priv;
728 int err;
729
730 priv = devm_kzalloc(
731 &wdev->dev, sizeof(struct dell_wmi_priv), GFP_KERNEL);
732 if (!priv)
733 return -ENOMEM;
734 dev_set_drvdata(&wdev->dev, priv);
735
736 err = dell_wmi_check_descriptor_buffer(wdev);
737 if (err)
738 return err;
739
740 return dell_wmi_input_setup(wdev);
741 }
742
dell_wmi_remove(struct wmi_device * wdev)743 static int dell_wmi_remove(struct wmi_device *wdev)
744 {
745 dell_wmi_input_destroy(wdev);
746 return 0;
747 }
748 static const struct wmi_device_id dell_wmi_id_table[] = {
749 { .guid_string = DELL_EVENT_GUID },
750 { },
751 };
752
753 static struct wmi_driver dell_wmi_driver = {
754 .driver = {
755 .name = "dell-wmi",
756 },
757 .id_table = dell_wmi_id_table,
758 .probe = dell_wmi_probe,
759 .remove = dell_wmi_remove,
760 .notify = dell_wmi_notify,
761 };
762
dell_wmi_init(void)763 static int __init dell_wmi_init(void)
764 {
765 int err;
766
767 dmi_check_system(dell_wmi_smbios_list);
768
769 if (wmi_requires_smbios_request) {
770 err = dell_wmi_events_set_enabled(true);
771 if (err) {
772 pr_err("Failed to enable WMI events\n");
773 return err;
774 }
775 }
776
777 return wmi_driver_register(&dell_wmi_driver);
778 }
779 module_init(dell_wmi_init);
780
dell_wmi_exit(void)781 static void __exit dell_wmi_exit(void)
782 {
783 if (wmi_requires_smbios_request)
784 dell_wmi_events_set_enabled(false);
785
786 wmi_driver_unregister(&dell_wmi_driver);
787 }
788 module_exit(dell_wmi_exit);
789