1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Dell WMI hotkeys
4  *
5  * Copyright (C) 2008 Red Hat <mjg@redhat.com>
6  * Copyright (C) 2014-2015 Pali Rohár <pali@kernel.org>
7  *
8  * Portions based on wistron_btns.c:
9  * Copyright (C) 2005 Miloslav Trmac <mitr@volny.cz>
10  * Copyright (C) 2005 Bernhard Rosenkraenzer <bero@arklinux.org>
11  * Copyright (C) 2005 Dmitry Torokhov <dtor@mail.ru>
12  */
13 
14 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
15 
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/init.h>
19 #include <linux/slab.h>
20 #include <linux/types.h>
21 #include <linux/input.h>
22 #include <linux/input/sparse-keymap.h>
23 #include <linux/acpi.h>
24 #include <linux/string.h>
25 #include <linux/dmi.h>
26 #include <linux/wmi.h>
27 #include <acpi/video.h>
28 #include "dell-smbios.h"
29 #include "dell-wmi-descriptor.h"
30 
31 MODULE_AUTHOR("Matthew Garrett <mjg@redhat.com>");
32 MODULE_AUTHOR("Pali Rohár <pali@kernel.org>");
33 MODULE_DESCRIPTION("Dell laptop WMI hotkeys driver");
34 MODULE_LICENSE("GPL");
35 
36 #define DELL_EVENT_GUID "9DBB5994-A997-11DA-B012-B622A1EF5492"
37 
38 static bool wmi_requires_smbios_request;
39 
40 struct dell_wmi_priv {
41 	struct input_dev *input_dev;
42 	u32 interface_version;
43 };
44 
dmi_matched(const struct dmi_system_id *dmi)45 static int __init dmi_matched(const struct dmi_system_id *dmi)
46 {
47 	wmi_requires_smbios_request = 1;
48 	return 1;
49 }
50 
51 static const struct dmi_system_id dell_wmi_smbios_list[] __initconst = {
52 	{
53 		.callback = dmi_matched,
54 		.ident = "Dell Inspiron M5110",
55 		.matches = {
56 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
57 			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron M5110"),
58 		},
59 	},
60 	{
61 		.callback = dmi_matched,
62 		.ident = "Dell Vostro V131",
63 		.matches = {
64 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
65 			DMI_MATCH(DMI_PRODUCT_NAME, "Vostro V131"),
66 		},
67 	},
68 	{ }
69 };
70 
71 /*
72  * Keymap for WMI events of type 0x0000
73  *
74  * Certain keys are flagged as KE_IGNORE. All of these are either
75  * notifications (rather than requests for change) or are also sent
76  * via the keyboard controller so should not be sent again.
77  */
78 static const struct key_entry dell_wmi_keymap_type_0000[] = {
79 	{ KE_IGNORE, 0x003a, { KEY_CAPSLOCK } },
80 
81 	/* Key code is followed by brightness level */
82 	{ KE_KEY,    0xe005, { KEY_BRIGHTNESSDOWN } },
83 	{ KE_KEY,    0xe006, { KEY_BRIGHTNESSUP } },
84 
85 	/* Battery health status button */
86 	{ KE_KEY,    0xe007, { KEY_BATTERY } },
87 
88 	/* Radio devices state change, key code is followed by other values */
89 	{ KE_IGNORE, 0xe008, { KEY_RFKILL } },
90 
91 	{ KE_KEY,    0xe009, { KEY_EJECTCD } },
92 
93 	/* Key code is followed by: next, active and attached devices */
94 	{ KE_KEY,    0xe00b, { KEY_SWITCHVIDEOMODE } },
95 
96 	/* Key code is followed by keyboard illumination level */
97 	{ KE_IGNORE, 0xe00c, { KEY_KBDILLUMTOGGLE } },
98 
99 	/* BIOS error detected */
100 	{ KE_IGNORE, 0xe00d, { KEY_RESERVED } },
101 
102 	/* Battery was removed or inserted */
103 	{ KE_IGNORE, 0xe00e, { KEY_RESERVED } },
104 
105 	/* Wifi Catcher */
106 	{ KE_KEY,    0xe011, { KEY_WLAN } },
107 
108 	/* Ambient light sensor toggle */
109 	{ KE_IGNORE, 0xe013, { KEY_RESERVED } },
110 
111 	{ KE_IGNORE, 0xe020, { KEY_MUTE } },
112 
113 	/* Unknown, defined in ACPI DSDT */
114 	/* { KE_IGNORE, 0xe023, { KEY_RESERVED } }, */
115 
116 	/* Untested, Dell Instant Launch key on Inspiron 7520 */
117 	/* { KE_IGNORE, 0xe024, { KEY_RESERVED } }, */
118 
119 	/* Dell Instant Launch key */
120 	{ KE_KEY,    0xe025, { KEY_PROG4 } },
121 
122 	/* Audio panel key */
123 	{ KE_IGNORE, 0xe026, { KEY_RESERVED } },
124 
125 	/* LCD Display On/Off Control key */
126 	{ KE_KEY,    0xe027, { KEY_DISPLAYTOGGLE } },
127 
128 	/* Untested, Multimedia key on Dell Vostro 3560 */
129 	/* { KE_IGNORE, 0xe028, { KEY_RESERVED } }, */
130 
131 	/* Dell Instant Launch key */
132 	{ KE_KEY,    0xe029, { KEY_PROG4 } },
133 
134 	/* Untested, Windows Mobility Center button on Inspiron 7520 */
135 	/* { KE_IGNORE, 0xe02a, { KEY_RESERVED } }, */
136 
137 	/* Unknown, defined in ACPI DSDT */
138 	/* { KE_IGNORE, 0xe02b, { KEY_RESERVED } }, */
139 
140 	/* Untested, Dell Audio With Preset Switch button on Inspiron 7520 */
141 	/* { KE_IGNORE, 0xe02c, { KEY_RESERVED } }, */
142 
143 	{ KE_IGNORE, 0xe02e, { KEY_VOLUMEDOWN } },
144 	{ KE_IGNORE, 0xe030, { KEY_VOLUMEUP } },
145 	{ KE_IGNORE, 0xe033, { KEY_KBDILLUMUP } },
146 	{ KE_IGNORE, 0xe034, { KEY_KBDILLUMDOWN } },
147 	{ KE_IGNORE, 0xe03a, { KEY_CAPSLOCK } },
148 
149 	/* NIC Link is Up */
150 	{ KE_IGNORE, 0xe043, { KEY_RESERVED } },
151 
152 	/* NIC Link is Down */
153 	{ KE_IGNORE, 0xe044, { KEY_RESERVED } },
154 
155 	/*
156 	 * This entry is very suspicious!
157 	 * Originally Matthew Garrett created this dell-wmi driver specially for
158 	 * "button with a picture of a battery" which has event code 0xe045.
159 	 * Later Mario Limonciello from Dell told us that event code 0xe045 is
160 	 * reported by Num Lock and should be ignored because key is send also
161 	 * by keyboard controller.
162 	 * So for now we will ignore this event to prevent potential double
163 	 * Num Lock key press.
164 	 */
165 	{ KE_IGNORE, 0xe045, { KEY_NUMLOCK } },
166 
167 	/* Scroll lock and also going to tablet mode on portable devices */
168 	{ KE_IGNORE, 0xe046, { KEY_SCROLLLOCK } },
169 
170 	/* Untested, going from tablet mode on portable devices */
171 	/* { KE_IGNORE, 0xe047, { KEY_RESERVED } }, */
172 
173 	/* Dell Support Center key */
174 	{ KE_IGNORE, 0xe06e, { KEY_RESERVED } },
175 
176 	{ KE_IGNORE, 0xe0f7, { KEY_MUTE } },
177 	{ KE_IGNORE, 0xe0f8, { KEY_VOLUMEDOWN } },
178 	{ KE_IGNORE, 0xe0f9, { KEY_VOLUMEUP } },
179 };
180 
181 struct dell_bios_keymap_entry {
182 	u16 scancode;
183 	u16 keycode;
184 };
185 
186 struct dell_bios_hotkey_table {
187 	struct dmi_header header;
188 	struct dell_bios_keymap_entry keymap[];
189 
190 };
191 
192 struct dell_dmi_results {
193 	int err;
194 	int keymap_size;
195 	struct key_entry *keymap;
196 };
197 
198 /* Uninitialized entries here are KEY_RESERVED == 0. */
199 static const u16 bios_to_linux_keycode[256] = {
200 	[0]	= KEY_MEDIA,
201 	[1]	= KEY_NEXTSONG,
202 	[2]	= KEY_PLAYPAUSE,
203 	[3]	= KEY_PREVIOUSSONG,
204 	[4]	= KEY_STOPCD,
205 	[5]	= KEY_UNKNOWN,
206 	[6]	= KEY_UNKNOWN,
207 	[7]	= KEY_UNKNOWN,
208 	[8]	= KEY_WWW,
209 	[9]	= KEY_UNKNOWN,
210 	[10]	= KEY_VOLUMEDOWN,
211 	[11]	= KEY_MUTE,
212 	[12]	= KEY_VOLUMEUP,
213 	[13]	= KEY_UNKNOWN,
214 	[14]	= KEY_BATTERY,
215 	[15]	= KEY_EJECTCD,
216 	[16]	= KEY_UNKNOWN,
217 	[17]	= KEY_SLEEP,
218 	[18]	= KEY_PROG1,
219 	[19]	= KEY_BRIGHTNESSDOWN,
220 	[20]	= KEY_BRIGHTNESSUP,
221 	[21]	= KEY_BRIGHTNESS_AUTO,
222 	[22]	= KEY_KBDILLUMTOGGLE,
223 	[23]	= KEY_UNKNOWN,
224 	[24]	= KEY_SWITCHVIDEOMODE,
225 	[25]	= KEY_UNKNOWN,
226 	[26]	= KEY_UNKNOWN,
227 	[27]	= KEY_SWITCHVIDEOMODE,
228 	[28]	= KEY_UNKNOWN,
229 	[29]	= KEY_UNKNOWN,
230 	[30]	= KEY_PROG2,
231 	[31]	= KEY_UNKNOWN,
232 	[32]	= KEY_UNKNOWN,
233 	[33]	= KEY_UNKNOWN,
234 	[34]	= KEY_UNKNOWN,
235 	[35]	= KEY_UNKNOWN,
236 	[36]	= KEY_UNKNOWN,
237 	[37]	= KEY_UNKNOWN,
238 	[38]	= KEY_MICMUTE,
239 	[255]	= KEY_PROG3,
240 };
241 
242 /*
243  * Keymap for WMI events of type 0x0010
244  *
245  * These are applied if the 0xB2 DMI hotkey table is present and doesn't
246  * override them.
247  */
248 static const struct key_entry dell_wmi_keymap_type_0010[] = {
249 	/* Fn-lock switched to function keys */
250 	{ KE_IGNORE, 0x0, { KEY_RESERVED } },
251 
252 	/* Fn-lock switched to multimedia keys */
253 	{ KE_IGNORE, 0x1, { KEY_RESERVED } },
254 
255 	/* Keyboard backlight change notification */
256 	{ KE_IGNORE, 0x3f, { KEY_RESERVED } },
257 
258 	/* Backlight brightness level */
259 	{ KE_KEY,    0x57, { KEY_BRIGHTNESSDOWN } },
260 	{ KE_KEY,    0x58, { KEY_BRIGHTNESSUP } },
261 
262 	/*Speaker Mute*/
263 	{ KE_KEY, 0x109, { KEY_MUTE} },
264 
265 	/* Mic mute */
266 	{ KE_KEY, 0x150, { KEY_MICMUTE } },
267 
268 	/* Fn-lock */
269 	{ KE_IGNORE, 0x151, { KEY_RESERVED } },
270 
271 	/* Change keyboard illumination */
272 	{ KE_IGNORE, 0x152, { KEY_KBDILLUMTOGGLE } },
273 
274 	/*
275 	 * Radio disable (notify only -- there is no model for which the
276 	 * WMI event is supposed to trigger an action).
277 	 */
278 	{ KE_IGNORE, 0x153, { KEY_RFKILL } },
279 
280 	/* RGB keyboard backlight control */
281 	{ KE_IGNORE, 0x154, { KEY_RESERVED } },
282 
283 	/*
284 	 * Stealth mode toggle. This will "disable all lights and sounds".
285 	 * The action is performed by the BIOS and EC; the WMI event is just
286 	 * a notification. On the XPS 13 9350, this is Fn+F7, and there's
287 	 * a BIOS setting to enable and disable the hotkey.
288 	 */
289 	{ KE_IGNORE, 0x155, { KEY_RESERVED } },
290 
291 	/* Rugged magnetic dock attach/detach events */
292 	{ KE_IGNORE, 0x156, { KEY_RESERVED } },
293 	{ KE_IGNORE, 0x157, { KEY_RESERVED } },
294 
295 	/* Rugged programmable (P1/P2/P3 keys) */
296 	{ KE_KEY,    0x850, { KEY_PROG1 } },
297 	{ KE_KEY,    0x851, { KEY_PROG2 } },
298 	{ KE_KEY,    0x852, { KEY_PROG3 } },
299 
300 	/*
301 	 * Radio disable (notify only -- there is no model for which the
302 	 * WMI event is supposed to trigger an action).
303 	 */
304 	{ KE_IGNORE, 0xe008, { KEY_RFKILL } },
305 
306 	/* Fn-lock */
307 	{ KE_IGNORE, 0xe035, { KEY_RESERVED } },
308 };
309 
310 /*
311  * Keymap for WMI events of type 0x0011
312  */
313 static const struct key_entry dell_wmi_keymap_type_0011[] = {
314 	/* Battery unplugged */
315 	{ KE_IGNORE, 0xfff0, { KEY_RESERVED } },
316 
317 	/* Battery inserted */
318 	{ KE_IGNORE, 0xfff1, { KEY_RESERVED } },
319 
320 	/*
321 	 * Detachable keyboard detached / undocked
322 	 * Note SW_TABLET_MODE is already reported through the intel_vbtn
323 	 * driver for this, so we ignore it.
324 	 */
325 	{ KE_IGNORE, 0xfff2, { KEY_RESERVED } },
326 
327 	/* Detachable keyboard attached / docked */
328 	{ KE_IGNORE, 0xfff3, { KEY_RESERVED } },
329 
330 	/* Keyboard backlight level changed */
331 	{ KE_IGNORE, KBD_LED_OFF_TOKEN,      { KEY_RESERVED } },
332 	{ KE_IGNORE, KBD_LED_ON_TOKEN,       { KEY_RESERVED } },
333 	{ KE_IGNORE, KBD_LED_AUTO_TOKEN,     { KEY_RESERVED } },
334 	{ KE_IGNORE, KBD_LED_AUTO_25_TOKEN,  { KEY_RESERVED } },
335 	{ KE_IGNORE, KBD_LED_AUTO_50_TOKEN,  { KEY_RESERVED } },
336 	{ KE_IGNORE, KBD_LED_AUTO_75_TOKEN,  { KEY_RESERVED } },
337 	{ KE_IGNORE, KBD_LED_AUTO_100_TOKEN, { KEY_RESERVED } },
338 };
339 
340 /*
341  * Keymap for WMI events of type 0x0012
342  * They are events with extended data
343  */
344 static const struct key_entry dell_wmi_keymap_type_0012[] = {
345 	/* Fn-lock button pressed */
346 	{ KE_IGNORE, 0xe035, { KEY_RESERVED } },
347 };
348 
dell_wmi_process_key(struct wmi_device *wdev, int type, int code)349 static void dell_wmi_process_key(struct wmi_device *wdev, int type, int code)
350 {
351 	struct dell_wmi_priv *priv = dev_get_drvdata(&wdev->dev);
352 	const struct key_entry *key;
353 
354 	key = sparse_keymap_entry_from_scancode(priv->input_dev,
355 						(type << 16) | code);
356 	if (!key) {
357 		pr_info("Unknown key with type 0x%04x and code 0x%04x pressed\n",
358 			type, code);
359 		return;
360 	}
361 
362 	pr_debug("Key with type 0x%04x and code 0x%04x pressed\n", type, code);
363 
364 	/* Don't report brightness notifications that will also come via ACPI */
365 	if ((key->keycode == KEY_BRIGHTNESSUP ||
366 	     key->keycode == KEY_BRIGHTNESSDOWN) &&
367 	    acpi_video_handles_brightness_key_presses())
368 		return;
369 
370 	if (type == 0x0000 && code == 0xe025 && !wmi_requires_smbios_request)
371 		return;
372 
373 	if (key->keycode == KEY_KBDILLUMTOGGLE)
374 		dell_laptop_call_notifier(
375 			DELL_LAPTOP_KBD_BACKLIGHT_BRIGHTNESS_CHANGED, NULL);
376 
377 	sparse_keymap_report_entry(priv->input_dev, key, 1, true);
378 }
379 
dell_wmi_notify(struct wmi_device *wdev, union acpi_object *obj)380 static void dell_wmi_notify(struct wmi_device *wdev,
381 			    union acpi_object *obj)
382 {
383 	struct dell_wmi_priv *priv = dev_get_drvdata(&wdev->dev);
384 	u16 *buffer_entry, *buffer_end;
385 	acpi_size buffer_size;
386 	int len, i;
387 
388 	if (obj->type != ACPI_TYPE_BUFFER) {
389 		pr_warn("bad response type %x\n", obj->type);
390 		return;
391 	}
392 
393 	pr_debug("Received WMI event (%*ph)\n",
394 		obj->buffer.length, obj->buffer.pointer);
395 
396 	buffer_entry = (u16 *)obj->buffer.pointer;
397 	buffer_size = obj->buffer.length/2;
398 	buffer_end = buffer_entry + buffer_size;
399 
400 	/*
401 	 * BIOS/ACPI on devices with WMI interface version 0 does not clear
402 	 * buffer before filling it. So next time when BIOS/ACPI send WMI event
403 	 * which is smaller as previous then it contains garbage in buffer from
404 	 * previous event.
405 	 *
406 	 * BIOS/ACPI on devices with WMI interface version 1 clears buffer and
407 	 * sometimes send more events in buffer at one call.
408 	 *
409 	 * So to prevent reading garbage from buffer we will process only first
410 	 * one event on devices with WMI interface version 0.
411 	 */
412 	if (priv->interface_version == 0 && buffer_entry < buffer_end)
413 		if (buffer_end > buffer_entry + buffer_entry[0] + 1)
414 			buffer_end = buffer_entry + buffer_entry[0] + 1;
415 
416 	while (buffer_entry < buffer_end) {
417 
418 		len = buffer_entry[0];
419 		if (len == 0)
420 			break;
421 
422 		len++;
423 
424 		if (buffer_entry + len > buffer_end) {
425 			pr_warn("Invalid length of WMI event\n");
426 			break;
427 		}
428 
429 		pr_debug("Process buffer (%*ph)\n", len*2, buffer_entry);
430 
431 		switch (buffer_entry[1]) {
432 		case 0x0000: /* One key pressed or event occurred */
433 		case 0x0012: /* Event with extended data occurred */
434 			if (len > 2)
435 				dell_wmi_process_key(wdev, buffer_entry[1],
436 						     buffer_entry[2]);
437 			/* Extended data is currently ignored */
438 			break;
439 		case 0x0010: /* Sequence of keys pressed */
440 		case 0x0011: /* Sequence of events occurred */
441 			for (i = 2; i < len; ++i)
442 				dell_wmi_process_key(wdev, buffer_entry[1],
443 						     buffer_entry[i]);
444 			break;
445 		default: /* Unknown event */
446 			pr_info("Unknown WMI event type 0x%x\n",
447 				(int)buffer_entry[1]);
448 			break;
449 		}
450 
451 		buffer_entry += len;
452 
453 	}
454 
455 }
456 
have_scancode(u32 scancode, const struct key_entry *keymap, int len)457 static bool have_scancode(u32 scancode, const struct key_entry *keymap, int len)
458 {
459 	int i;
460 
461 	for (i = 0; i < len; i++)
462 		if (keymap[i].code == scancode)
463 			return true;
464 
465 	return false;
466 }
467 
handle_dmi_entry(const struct dmi_header *dm, void *opaque)468 static void handle_dmi_entry(const struct dmi_header *dm, void *opaque)
469 {
470 	struct dell_dmi_results *results = opaque;
471 	struct dell_bios_hotkey_table *table;
472 	int hotkey_num, i, pos = 0;
473 	struct key_entry *keymap;
474 
475 	if (results->err || results->keymap)
476 		return;		/* We already found the hotkey table. */
477 
478 	/* The Dell hotkey table is type 0xB2.  Scan until we find it. */
479 	if (dm->type != 0xb2)
480 		return;
481 
482 	table = container_of(dm, struct dell_bios_hotkey_table, header);
483 
484 	hotkey_num = (table->header.length -
485 		      sizeof(struct dell_bios_hotkey_table)) /
486 				sizeof(struct dell_bios_keymap_entry);
487 	if (hotkey_num < 1) {
488 		/*
489 		 * Historically, dell-wmi would ignore a DMI entry of
490 		 * fewer than 7 bytes.  Sizes between 4 and 8 bytes are
491 		 * nonsensical (both the header and all entries are 4
492 		 * bytes), so we approximate the old behavior by
493 		 * ignoring tables with fewer than one entry.
494 		 */
495 		return;
496 	}
497 
498 	keymap = kcalloc(hotkey_num, sizeof(struct key_entry), GFP_KERNEL);
499 	if (!keymap) {
500 		results->err = -ENOMEM;
501 		return;
502 	}
503 
504 	for (i = 0; i < hotkey_num; i++) {
505 		const struct dell_bios_keymap_entry *bios_entry =
506 					&table->keymap[i];
507 
508 		/* Uninitialized entries are 0 aka KEY_RESERVED. */
509 		u16 keycode = (bios_entry->keycode <
510 			       ARRAY_SIZE(bios_to_linux_keycode)) ?
511 			bios_to_linux_keycode[bios_entry->keycode] :
512 			(bios_entry->keycode == 0xffff ? KEY_UNKNOWN : KEY_RESERVED);
513 
514 		/*
515 		 * Log if we find an entry in the DMI table that we don't
516 		 * understand.  If this happens, we should figure out what
517 		 * the entry means and add it to bios_to_linux_keycode.
518 		 */
519 		if (keycode == KEY_RESERVED) {
520 			pr_info("firmware scancode 0x%x maps to unrecognized keycode 0x%x\n",
521 				bios_entry->scancode, bios_entry->keycode);
522 			continue;
523 		}
524 
525 		if (keycode == KEY_KBDILLUMTOGGLE)
526 			keymap[pos].type = KE_IGNORE;
527 		else
528 			keymap[pos].type = KE_KEY;
529 		keymap[pos].code = bios_entry->scancode;
530 		keymap[pos].keycode = keycode;
531 
532 		pos++;
533 	}
534 
535 	results->keymap = keymap;
536 	results->keymap_size = pos;
537 }
538 
dell_wmi_input_setup(struct wmi_device *wdev)539 static int dell_wmi_input_setup(struct wmi_device *wdev)
540 {
541 	struct dell_wmi_priv *priv = dev_get_drvdata(&wdev->dev);
542 	struct dell_dmi_results dmi_results = {};
543 	struct key_entry *keymap;
544 	int err, i, pos = 0;
545 
546 	priv->input_dev = input_allocate_device();
547 	if (!priv->input_dev)
548 		return -ENOMEM;
549 
550 	priv->input_dev->name = "Dell WMI hotkeys";
551 	priv->input_dev->id.bustype = BUS_HOST;
552 	priv->input_dev->dev.parent = &wdev->dev;
553 
554 	if (dmi_walk(handle_dmi_entry, &dmi_results)) {
555 		/*
556 		 * Historically, dell-wmi ignored dmi_walk errors.  A failure
557 		 * is certainly surprising, but it probably just indicates
558 		 * a very old laptop.
559 		 */
560 		pr_warn("no DMI; using the old-style hotkey interface\n");
561 	}
562 
563 	if (dmi_results.err) {
564 		err = dmi_results.err;
565 		goto err_free_dev;
566 	}
567 
568 	keymap = kcalloc(dmi_results.keymap_size +
569 			 ARRAY_SIZE(dell_wmi_keymap_type_0000) +
570 			 ARRAY_SIZE(dell_wmi_keymap_type_0010) +
571 			 ARRAY_SIZE(dell_wmi_keymap_type_0011) +
572 			 ARRAY_SIZE(dell_wmi_keymap_type_0012) +
573 			 1,
574 			 sizeof(struct key_entry), GFP_KERNEL);
575 	if (!keymap) {
576 		kfree(dmi_results.keymap);
577 		err = -ENOMEM;
578 		goto err_free_dev;
579 	}
580 
581 	/* Append table with events of type 0x0010 which comes from DMI */
582 	for (i = 0; i < dmi_results.keymap_size; i++) {
583 		keymap[pos] = dmi_results.keymap[i];
584 		keymap[pos].code |= (0x0010 << 16);
585 		pos++;
586 	}
587 
588 	kfree(dmi_results.keymap);
589 
590 	/* Append table with extra events of type 0x0010 which are not in DMI */
591 	for (i = 0; i < ARRAY_SIZE(dell_wmi_keymap_type_0010); i++) {
592 		const struct key_entry *entry = &dell_wmi_keymap_type_0010[i];
593 
594 		/*
595 		 * Check if we've already found this scancode.  This takes
596 		 * quadratic time, but it doesn't matter unless the list
597 		 * of extra keys gets very long.
598 		 */
599 		if (dmi_results.keymap_size &&
600 		    have_scancode(entry->code | (0x0010 << 16),
601 				  keymap, dmi_results.keymap_size)
602 		   )
603 			continue;
604 
605 		keymap[pos] = *entry;
606 		keymap[pos].code |= (0x0010 << 16);
607 		pos++;
608 	}
609 
610 	/* Append table with events of type 0x0011 */
611 	for (i = 0; i < ARRAY_SIZE(dell_wmi_keymap_type_0011); i++) {
612 		keymap[pos] = dell_wmi_keymap_type_0011[i];
613 		keymap[pos].code |= (0x0011 << 16);
614 		pos++;
615 	}
616 
617 	/* Append table with events of type 0x0012 */
618 	for (i = 0; i < ARRAY_SIZE(dell_wmi_keymap_type_0012); i++) {
619 		keymap[pos] = dell_wmi_keymap_type_0012[i];
620 		keymap[pos].code |= (0x0012 << 16);
621 		pos++;
622 	}
623 
624 	/*
625 	 * Now append also table with "legacy" events of type 0x0000. Some of
626 	 * them are reported also on laptops which have scancodes in DMI.
627 	 */
628 	for (i = 0; i < ARRAY_SIZE(dell_wmi_keymap_type_0000); i++) {
629 		keymap[pos] = dell_wmi_keymap_type_0000[i];
630 		pos++;
631 	}
632 
633 	keymap[pos].type = KE_END;
634 
635 	err = sparse_keymap_setup(priv->input_dev, keymap, NULL);
636 	/*
637 	 * Sparse keymap library makes a copy of keymap so we don't need the
638 	 * original one that was allocated.
639 	 */
640 	kfree(keymap);
641 	if (err)
642 		goto err_free_dev;
643 
644 	err = input_register_device(priv->input_dev);
645 	if (err)
646 		goto err_free_dev;
647 
648 	return 0;
649 
650  err_free_dev:
651 	input_free_device(priv->input_dev);
652 	return err;
653 }
654 
dell_wmi_input_destroy(struct wmi_device *wdev)655 static void dell_wmi_input_destroy(struct wmi_device *wdev)
656 {
657 	struct dell_wmi_priv *priv = dev_get_drvdata(&wdev->dev);
658 
659 	input_unregister_device(priv->input_dev);
660 }
661 
662 /*
663  * According to Dell SMBIOS documentation:
664  *
665  * 17  3  Application Program Registration
666  *
667  *     cbArg1 Application ID 1 = 0x00010000
668  *     cbArg2 Application ID 2
669  *            QUICKSET/DCP = 0x51534554 "QSET"
670  *            ALS Driver   = 0x416c7353 "AlsS"
671  *            Latitude ON  = 0x4c6f6e52 "LonR"
672  *     cbArg3 Application version or revision number
673  *     cbArg4 0 = Unregister application
674  *            1 = Register application
675  *     cbRes1 Standard return codes (0, -1, -2)
676  */
677 
dell_wmi_events_set_enabled(bool enable)678 static int dell_wmi_events_set_enabled(bool enable)
679 {
680 	struct calling_interface_buffer *buffer;
681 	int ret;
682 
683 	buffer = kzalloc(sizeof(struct calling_interface_buffer), GFP_KERNEL);
684 	if (!buffer)
685 		return -ENOMEM;
686 	buffer->cmd_class = CLASS_INFO;
687 	buffer->cmd_select = SELECT_APP_REGISTRATION;
688 	buffer->input[0] = 0x10000;
689 	buffer->input[1] = 0x51534554;
690 	buffer->input[3] = enable;
691 	ret = dell_smbios_call(buffer);
692 	if (ret == 0)
693 		ret = buffer->output[0];
694 	kfree(buffer);
695 
696 	return dell_smbios_error(ret);
697 }
698 
dell_wmi_probe(struct wmi_device *wdev, const void *context)699 static int dell_wmi_probe(struct wmi_device *wdev, const void *context)
700 {
701 	struct dell_wmi_priv *priv;
702 	int ret;
703 
704 	ret = dell_wmi_get_descriptor_valid();
705 	if (ret)
706 		return ret;
707 
708 	priv = devm_kzalloc(
709 		&wdev->dev, sizeof(struct dell_wmi_priv), GFP_KERNEL);
710 	if (!priv)
711 		return -ENOMEM;
712 	dev_set_drvdata(&wdev->dev, priv);
713 
714 	if (!dell_wmi_get_interface_version(&priv->interface_version))
715 		return -EPROBE_DEFER;
716 
717 	return dell_wmi_input_setup(wdev);
718 }
719 
dell_wmi_remove(struct wmi_device *wdev)720 static int dell_wmi_remove(struct wmi_device *wdev)
721 {
722 	dell_wmi_input_destroy(wdev);
723 	return 0;
724 }
725 static const struct wmi_device_id dell_wmi_id_table[] = {
726 	{ .guid_string = DELL_EVENT_GUID },
727 	{ },
728 };
729 
730 static struct wmi_driver dell_wmi_driver = {
731 	.driver = {
732 		.name = "dell-wmi",
733 	},
734 	.id_table = dell_wmi_id_table,
735 	.probe = dell_wmi_probe,
736 	.remove = dell_wmi_remove,
737 	.notify = dell_wmi_notify,
738 };
739 
dell_wmi_init(void)740 static int __init dell_wmi_init(void)
741 {
742 	int err;
743 
744 	dmi_check_system(dell_wmi_smbios_list);
745 
746 	if (wmi_requires_smbios_request) {
747 		err = dell_wmi_events_set_enabled(true);
748 		if (err) {
749 			pr_err("Failed to enable WMI events\n");
750 			return err;
751 		}
752 	}
753 
754 	return wmi_driver_register(&dell_wmi_driver);
755 }
756 late_initcall(dell_wmi_init);
757 
dell_wmi_exit(void)758 static void __exit dell_wmi_exit(void)
759 {
760 	if (wmi_requires_smbios_request)
761 		dell_wmi_events_set_enabled(false);
762 
763 	wmi_driver_unregister(&dell_wmi_driver);
764 }
765 module_exit(dell_wmi_exit);
766 
767 MODULE_DEVICE_TABLE(wmi, dell_wmi_id_table);
768