xref: /linux/drivers/platform/x86/dell/dell-wmi-base.c (revision 5b05bb3f6c5716fab6911e12d60dd1f43ad9806a)
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/compiler_attributes.h>
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/init.h>
20 #include <linux/slab.h>
21 #include <linux/types.h>
22 #include <linux/input.h>
23 #include <linux/input/sparse-keymap.h>
24 #include <linux/acpi.h>
25 #include <linux/string.h>
26 #include <linux/dmi.h>
27 #include <linux/wmi.h>
28 #include <acpi/video.h>
29 #include "dell-smbios.h"
30 #include "dell-wmi-descriptor.h"
31 #include "dell-wmi-privacy.h"
32 
33 MODULE_AUTHOR("Matthew Garrett <mjg@redhat.com>");
34 MODULE_AUTHOR("Pali Rohár <pali@kernel.org>");
35 MODULE_DESCRIPTION("Dell laptop WMI hotkeys driver");
36 MODULE_LICENSE("GPL");
37 
38 #define DELL_EVENT_GUID "9DBB5994-A997-11DA-B012-B622A1EF5492"
39 
40 static bool wmi_requires_smbios_request;
41 
42 struct dell_wmi_priv {
43 	struct input_dev *input_dev;
44 	struct input_dev *tabletswitch_dev;
45 	u32 interface_version;
46 };
47 
dmi_matched(const struct dmi_system_id * dmi)48 static int __init dmi_matched(const struct dmi_system_id *dmi)
49 {
50 	wmi_requires_smbios_request = 1;
51 	return 1;
52 }
53 
54 static const struct dmi_system_id dell_wmi_smbios_list[] __initconst = {
55 	{
56 		.callback = dmi_matched,
57 		.ident = "Dell Inspiron M5110",
58 		.matches = {
59 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
60 			DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron M5110"),
61 		},
62 	},
63 	{
64 		.callback = dmi_matched,
65 		.ident = "Dell Vostro V131",
66 		.matches = {
67 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
68 			DMI_MATCH(DMI_PRODUCT_NAME, "Vostro V131"),
69 		},
70 	},
71 	{ }
72 };
73 
74 /*
75  * Keymap for WMI events of type 0x0000
76  *
77  * Certain keys are flagged as KE_IGNORE. All of these are either
78  * notifications (rather than requests for change) or are also sent
79  * via the keyboard controller so should not be sent again.
80  */
81 static const struct key_entry dell_wmi_keymap_type_0000[] = {
82 	{ KE_IGNORE, 0x003a, { KEY_CAPSLOCK } },
83 
84 	/* Audio mute toggle */
85 	{ KE_KEY,    0x0109, { KEY_MUTE } },
86 
87 	/* Mic mute toggle */
88 	{ KE_KEY,    0x0150, { KEY_MICMUTE } },
89 
90 	/* Meta key lock */
91 	{ KE_IGNORE, 0xe000, { KEY_RIGHTMETA } },
92 
93 	/* Meta key unlock */
94 	{ KE_IGNORE, 0xe001, { KEY_RIGHTMETA } },
95 
96 	/* Key code is followed by brightness level */
97 	{ KE_KEY,    0xe005, { KEY_BRIGHTNESSDOWN } },
98 	{ KE_KEY,    0xe006, { KEY_BRIGHTNESSUP } },
99 
100 	/* Battery health status button */
101 	{ KE_KEY,    0xe007, { KEY_BATTERY } },
102 
103 	/* Radio devices state change, key code is followed by other values */
104 	{ KE_IGNORE, 0xe008, { KEY_RFKILL } },
105 
106 	{ KE_KEY,    0xe009, { KEY_EJECTCD } },
107 
108 	/* Key code is followed by: next, active and attached devices */
109 	{ KE_KEY,    0xe00b, { KEY_SWITCHVIDEOMODE } },
110 
111 	/* Key code is followed by keyboard illumination level */
112 	{ KE_IGNORE, 0xe00c, { KEY_KBDILLUMTOGGLE } },
113 
114 	/* BIOS error detected */
115 	{ KE_IGNORE, 0xe00d, { KEY_RESERVED } },
116 
117 	/* Battery was removed or inserted */
118 	{ KE_IGNORE, 0xe00e, { KEY_RESERVED } },
119 
120 	/* Wifi Catcher */
121 	{ KE_KEY,    0xe011, { KEY_WLAN } },
122 
123 	/* Ambient light sensor toggle */
124 	{ KE_IGNORE, 0xe013, { KEY_RESERVED } },
125 
126 	{ KE_IGNORE, 0xe020, { KEY_MUTE } },
127 
128 	/* Unknown, defined in ACPI DSDT */
129 	/* { KE_IGNORE, 0xe023, { KEY_RESERVED } }, */
130 
131 	/* Untested, Dell Instant Launch key on Inspiron 7520 */
132 	/* { KE_IGNORE, 0xe024, { KEY_RESERVED } }, */
133 
134 	/* Dell Instant Launch key */
135 	{ KE_KEY,    0xe025, { KEY_PROG4 } },
136 
137 	/* Audio panel key */
138 	{ KE_IGNORE, 0xe026, { KEY_RESERVED } },
139 
140 	/* LCD Display On/Off Control key */
141 	{ KE_KEY,    0xe027, { KEY_DISPLAYTOGGLE } },
142 
143 	/* Untested, Multimedia key on Dell Vostro 3560 */
144 	/* { KE_IGNORE, 0xe028, { KEY_RESERVED } }, */
145 
146 	/* Dell Instant Launch key */
147 	{ KE_KEY,    0xe029, { KEY_PROG4 } },
148 
149 	/* Untested, Windows Mobility Center button on Inspiron 7520 */
150 	/* { KE_IGNORE, 0xe02a, { KEY_RESERVED } }, */
151 
152 	/* Unknown, defined in ACPI DSDT */
153 	/* { KE_IGNORE, 0xe02b, { KEY_RESERVED } }, */
154 
155 	/* Untested, Dell Audio With Preset Switch button on Inspiron 7520 */
156 	/* { KE_IGNORE, 0xe02c, { KEY_RESERVED } }, */
157 
158 	{ KE_IGNORE, 0xe02e, { KEY_VOLUMEDOWN } },
159 	{ KE_IGNORE, 0xe030, { KEY_VOLUMEUP } },
160 	{ KE_IGNORE, 0xe033, { KEY_KBDILLUMUP } },
161 	{ KE_IGNORE, 0xe034, { KEY_KBDILLUMDOWN } },
162 	{ KE_IGNORE, 0xe03a, { KEY_CAPSLOCK } },
163 
164 	/* NIC Link is Up */
165 	{ KE_IGNORE, 0xe043, { KEY_RESERVED } },
166 
167 	/* NIC Link is Down */
168 	{ KE_IGNORE, 0xe044, { KEY_RESERVED } },
169 
170 	/*
171 	 * This entry is very suspicious!
172 	 * Originally Matthew Garrett created this dell-wmi driver specially for
173 	 * "button with a picture of a battery" which has event code 0xe045.
174 	 * Later Mario Limonciello from Dell told us that event code 0xe045 is
175 	 * reported by Num Lock and should be ignored because key is send also
176 	 * by keyboard controller.
177 	 * So for now we will ignore this event to prevent potential double
178 	 * Num Lock key press.
179 	 */
180 	{ KE_IGNORE, 0xe045, { KEY_NUMLOCK } },
181 
182 	/* Scroll lock and also going to tablet mode on portable devices */
183 	{ KE_IGNORE, 0xe046, { KEY_SCROLLLOCK } },
184 
185 	/* Untested, going from tablet mode on portable devices */
186 	/* { KE_IGNORE, 0xe047, { KEY_RESERVED } }, */
187 
188 	/* Dell Support Center key */
189 	{ KE_IGNORE, 0xe06e, { KEY_RESERVED } },
190 
191 	{ KE_IGNORE, 0xe0f7, { KEY_MUTE } },
192 	{ KE_IGNORE, 0xe0f8, { KEY_VOLUMEDOWN } },
193 	{ KE_IGNORE, 0xe0f9, { KEY_VOLUMEUP } },
194 };
195 
196 struct dell_bios_keymap_entry {
197 	u16 scancode;
198 	u16 keycode;
199 };
200 
201 struct dell_bios_hotkey_table {
202 	struct dmi_header header;
203 	struct dell_bios_keymap_entry keymap[];
204 
205 };
206 
207 struct dell_dmi_results {
208 	int err;
209 	int keymap_size;
210 	struct key_entry *keymap;
211 };
212 
213 /* Uninitialized entries here are KEY_RESERVED == 0. */
214 static const u16 bios_to_linux_keycode[256] = {
215 	[0]	= KEY_MEDIA,
216 	[1]	= KEY_NEXTSONG,
217 	[2]	= KEY_PLAYPAUSE,
218 	[3]	= KEY_PREVIOUSSONG,
219 	[4]	= KEY_STOPCD,
220 	[5]	= KEY_UNKNOWN,
221 	[6]	= KEY_UNKNOWN,
222 	[7]	= KEY_UNKNOWN,
223 	[8]	= KEY_WWW,
224 	[9]	= KEY_UNKNOWN,
225 	[10]	= KEY_VOLUMEDOWN,
226 	[11]	= KEY_MUTE,
227 	[12]	= KEY_VOLUMEUP,
228 	[13]	= KEY_UNKNOWN,
229 	[14]	= KEY_BATTERY,
230 	[15]	= KEY_EJECTCD,
231 	[16]	= KEY_UNKNOWN,
232 	[17]	= KEY_SLEEP,
233 	[18]	= KEY_PROG1,
234 	[19]	= KEY_BRIGHTNESSDOWN,
235 	[20]	= KEY_BRIGHTNESSUP,
236 	[21]	= KEY_BRIGHTNESS_AUTO,
237 	[22]	= KEY_KBDILLUMTOGGLE,
238 	[23]	= KEY_UNKNOWN,
239 	[24]	= KEY_SWITCHVIDEOMODE,
240 	[25]	= KEY_UNKNOWN,
241 	[26]	= KEY_UNKNOWN,
242 	[27]	= KEY_SWITCHVIDEOMODE,
243 	[28]	= KEY_UNKNOWN,
244 	[29]	= KEY_UNKNOWN,
245 	[30]	= KEY_PROG2,
246 	[31]	= KEY_UNKNOWN,
247 	[32]	= KEY_UNKNOWN,
248 	[33]	= KEY_UNKNOWN,
249 	[34]	= KEY_UNKNOWN,
250 	[35]	= KEY_UNKNOWN,
251 	[36]	= KEY_UNKNOWN,
252 	[37]	= KEY_UNKNOWN,
253 	[38]	= KEY_MICMUTE,
254 	[255]	= KEY_PROG3,
255 };
256 
257 /*
258  * Keymap for WMI events of type 0x0010
259  *
260  * These are applied if the 0xB2 DMI hotkey table is present and doesn't
261  * override them.
262  */
263 static const struct key_entry dell_wmi_keymap_type_0010[] = {
264 	/* Fn-lock switched to function keys */
265 	{ KE_IGNORE, 0x0, { KEY_RESERVED } },
266 
267 	/* Fn-lock switched to multimedia keys */
268 	{ KE_IGNORE, 0x1, { KEY_RESERVED } },
269 
270 	/* Keyboard backlight change notification */
271 	{ KE_IGNORE, 0x3f, { KEY_RESERVED } },
272 
273 	/* Backlight brightness level */
274 	{ KE_KEY,    0x57, { KEY_BRIGHTNESSDOWN } },
275 	{ KE_KEY,    0x58, { KEY_BRIGHTNESSUP } },
276 
277 	/*Speaker Mute*/
278 	{ KE_KEY, 0x109, { KEY_MUTE} },
279 
280 	/* S2Idle screen off */
281 	{ KE_IGNORE, 0x120, { KEY_RESERVED }},
282 
283 	/* Leaving S4 or S2Idle suspend */
284 	{ KE_IGNORE, 0x130, { KEY_RESERVED }},
285 
286 	/* Entering S2Idle suspend */
287 	{ KE_IGNORE, 0x140, { KEY_RESERVED }},
288 
289 	/* Mic mute */
290 	{ KE_KEY, 0x150, { KEY_MICMUTE } },
291 
292 	/* Fn-lock */
293 	{ KE_IGNORE, 0x151, { KEY_RESERVED } },
294 
295 	/* Change keyboard illumination */
296 	{ KE_IGNORE, 0x152, { KEY_KBDILLUMTOGGLE } },
297 
298 	/*
299 	 * Radio disable (notify only -- there is no model for which the
300 	 * WMI event is supposed to trigger an action).
301 	 */
302 	{ KE_IGNORE, 0x153, { KEY_RFKILL } },
303 
304 	/* RGB keyboard backlight control */
305 	{ KE_IGNORE, 0x154, { KEY_RESERVED } },
306 
307 	/*
308 	 * Stealth mode toggle. This will "disable all lights and sounds".
309 	 * The action is performed by the BIOS and EC; the WMI event is just
310 	 * a notification. On the XPS 13 9350, this is Fn+F7, and there's
311 	 * a BIOS setting to enable and disable the hotkey.
312 	 */
313 	{ KE_IGNORE, 0x155, { KEY_RESERVED } },
314 
315 	/* Rugged magnetic dock attach/detach events */
316 	{ KE_IGNORE, 0x156, { KEY_RESERVED } },
317 	{ KE_IGNORE, 0x157, { KEY_RESERVED } },
318 
319 	/* Rugged programmable (P1/P2/P3 keys) */
320 	{ KE_KEY,    0x850, { KEY_PROG1 } },
321 	{ KE_KEY,    0x851, { KEY_PROG2 } },
322 	{ KE_KEY,    0x852, { KEY_PROG3 } },
323 
324 	/*
325 	 * Radio disable (notify only -- there is no model for which the
326 	 * WMI event is supposed to trigger an action).
327 	 */
328 	{ KE_IGNORE, 0xe008, { KEY_RFKILL } },
329 
330 	/* Fn-lock */
331 	{ KE_IGNORE, 0xe035, { KEY_RESERVED } },
332 };
333 
334 /*
335  * Keymap for WMI events of type 0x0011
336  */
337 static const struct key_entry dell_wmi_keymap_type_0011[] = {
338 	/* Reflex keyboard switch on 2n1 devices */
339 	{ KE_IGNORE, 0xe070, { KEY_RESERVED } },
340 
341 	/* Battery unplugged */
342 	{ KE_IGNORE, 0xfff0, { KEY_RESERVED } },
343 
344 	/* Battery inserted */
345 	{ KE_IGNORE, 0xfff1, { KEY_RESERVED } },
346 
347 	/*
348 	 * Detachable keyboard detached / undocked
349 	 * Note SW_TABLET_MODE is already reported through the intel_vbtn
350 	 * driver for this, so we ignore it.
351 	 */
352 	{ KE_IGNORE, 0xfff2, { KEY_RESERVED } },
353 
354 	/* Detachable keyboard attached / docked */
355 	{ KE_IGNORE, 0xfff3, { KEY_RESERVED } },
356 
357 	/* Keyboard backlight level changed */
358 	{ KE_IGNORE, KBD_LED_OFF_TOKEN,      { KEY_RESERVED } },
359 	{ KE_IGNORE, KBD_LED_ON_TOKEN,       { KEY_RESERVED } },
360 	{ KE_IGNORE, KBD_LED_AUTO_TOKEN,     { KEY_RESERVED } },
361 	{ KE_IGNORE, KBD_LED_AUTO_25_TOKEN,  { KEY_RESERVED } },
362 	{ KE_IGNORE, KBD_LED_AUTO_50_TOKEN,  { KEY_RESERVED } },
363 	{ KE_IGNORE, KBD_LED_AUTO_75_TOKEN,  { KEY_RESERVED } },
364 	{ KE_IGNORE, KBD_LED_AUTO_100_TOKEN, { KEY_RESERVED } },
365 };
366 
367 /*
368  * Keymap for WMI events of type 0x0012
369  * They are events with extended data
370  */
371 static const struct key_entry dell_wmi_keymap_type_0012[] = {
372 	/* Backlight brightness change event */
373 	{ KE_IGNORE, 0x0003, { KEY_RESERVED } },
374 
375 	/*
376 	 * Electronic privacy screen toggled, extended data gives state,
377 	 * separate entries for on/off see handling in dell_wmi_process_key().
378 	 */
379 	{ KE_KEY, 0x000c, { KEY_EPRIVACY_SCREEN_OFF } },
380 	{ KE_KEY, 0x000c, { KEY_EPRIVACY_SCREEN_ON } },
381 
382 	/* Ultra-performance mode switch request */
383 	{ KE_IGNORE, 0x000d, { KEY_RESERVED } },
384 
385 	/* Fn-lock button pressed */
386 	{ KE_IGNORE, 0xe035, { KEY_RESERVED } },
387 };
388 
dell_wmi_switch_event(struct input_dev ** subdev,const char * devname,int switchid,int value)389 static void dell_wmi_switch_event(struct input_dev **subdev,
390 				  const char *devname,
391 				  int switchid,
392 				  int value)
393 {
394 	if (!*subdev) {
395 		struct input_dev *dev = input_allocate_device();
396 
397 		if (!dev) {
398 			pr_warn("could not allocate device for %s\n", devname);
399 			return;
400 		}
401 		__set_bit(EV_SW, (dev)->evbit);
402 		__set_bit(switchid, (dev)->swbit);
403 
404 		(dev)->name = devname;
405 		(dev)->id.bustype = BUS_HOST;
406 		if (input_register_device(dev)) {
407 			input_free_device(dev);
408 			pr_warn("could not register device for %s\n", devname);
409 			return;
410 		}
411 		*subdev = dev;
412 	}
413 
414 	input_report_switch(*subdev, switchid, value);
415 	input_sync(*subdev);
416 }
417 
dell_wmi_process_key(struct wmi_device * wdev,int type,int code,__le16 * buffer,int remaining)418 static int dell_wmi_process_key(struct wmi_device *wdev, int type, int code, __le16 *buffer,
419 				int remaining)
420 {
421 	struct dell_wmi_priv *priv = dev_get_drvdata(&wdev->dev);
422 	const struct key_entry *key;
423 	int used = 0;
424 	int value = 1;
425 
426 	key = sparse_keymap_entry_from_scancode(priv->input_dev,
427 						(type << 16) | code);
428 	if (!key) {
429 		pr_info("Unknown key with type 0x%04x and code 0x%04x pressed\n",
430 			type, code);
431 		return 0;
432 	}
433 
434 	pr_debug("Key with type 0x%04x and code 0x%04x pressed\n", type, code);
435 
436 	/* Don't report brightness notifications that will also come via ACPI */
437 	if ((key->keycode == KEY_BRIGHTNESSUP ||
438 	     key->keycode == KEY_BRIGHTNESSDOWN) &&
439 	    acpi_video_handles_brightness_key_presses())
440 		return 0;
441 
442 	if (type == 0x0000 && code == 0xe025 && !wmi_requires_smbios_request)
443 		return 0;
444 
445 	if (key->keycode == KEY_KBDILLUMTOGGLE) {
446 		dell_laptop_call_notifier(
447 			DELL_LAPTOP_KBD_BACKLIGHT_BRIGHTNESS_CHANGED, NULL);
448 	} else if (type == 0x0011 && code == 0xe070 && remaining > 0) {
449 		dell_wmi_switch_event(&priv->tabletswitch_dev,
450 				      "Dell tablet mode switch",
451 				      SW_TABLET_MODE, !le16_to_cpu(buffer[0]));
452 		return 1;
453 	} else if (type == 0x0012 && code == 0x000c && remaining > 0) {
454 		/* Eprivacy toggle, switch to "on" key entry for on events */
455 		if (le16_to_cpu(buffer[0]) == 2)
456 			key++;
457 		used = 1;
458 	} else if (type == 0x0012 && code == 0x000d && remaining > 0) {
459 		value = (le16_to_cpu(buffer[0]) == 2);
460 		used = 1;
461 	}
462 
463 	sparse_keymap_report_entry(priv->input_dev, key, value, true);
464 
465 	return used;
466 }
467 
dell_wmi_notify(struct wmi_device * wdev,const struct wmi_buffer * buffer)468 static void dell_wmi_notify(struct wmi_device *wdev, const struct wmi_buffer *buffer)
469 {
470 	struct dell_wmi_priv *priv = dev_get_drvdata(&wdev->dev);
471 	__le16 *buffer_entry, *buffer_end;
472 	size_t buffer_size;
473 	int len, i;
474 
475 	pr_debug("Received WMI event (%*ph)\n", (int)buffer->length, buffer->data);
476 
477 	buffer_entry = buffer->data;
478 	buffer_size = buffer->length / 2;
479 	buffer_end = buffer_entry + buffer_size;
480 
481 	/*
482 	 * BIOS/ACPI on devices with WMI interface version 0 does not clear
483 	 * buffer before filling it. So next time when BIOS/ACPI send WMI event
484 	 * which is smaller as previous then it contains garbage in buffer from
485 	 * previous event.
486 	 *
487 	 * BIOS/ACPI on devices with WMI interface version 1 clears buffer and
488 	 * sometimes send more events in buffer at one call.
489 	 *
490 	 * So to prevent reading garbage from buffer we will process only first
491 	 * one event on devices with WMI interface version 0.
492 	 */
493 	if (priv->interface_version == 0 && buffer_entry < buffer_end)
494 		if (buffer_end > buffer_entry + le16_to_cpu(buffer_entry[0]) + 1)
495 			buffer_end = buffer_entry + le16_to_cpu(buffer_entry[0]) + 1;
496 
497 	while (buffer_entry < buffer_end) {
498 
499 		len = le16_to_cpu(buffer_entry[0]);
500 		if (len == 0)
501 			break;
502 
503 		len++;
504 
505 		if (buffer_entry + len > buffer_end) {
506 			pr_warn("Invalid length of WMI event\n");
507 			break;
508 		}
509 
510 		pr_debug("Process buffer (%*ph)\n", len*2, buffer_entry);
511 
512 		switch (le16_to_cpu(buffer_entry[1])) {
513 		case 0x0000: /* One key pressed or event occurred */
514 			if (len > 2)
515 				dell_wmi_process_key(wdev, le16_to_cpu(buffer_entry[1]),
516 						     le16_to_cpu(buffer_entry[2]),
517 						     buffer_entry + 3,
518 						     len - 3);
519 			/* Extended data is currently ignored */
520 			break;
521 		case 0x0010: /* Sequence of keys pressed */
522 		case 0x0011: /* Sequence of events occurred */
523 			for (i = 2; i < len; ++i)
524 				i += dell_wmi_process_key(wdev, le16_to_cpu(buffer_entry[1]),
525 							  le16_to_cpu(buffer_entry[i]),
526 							  buffer_entry + i,
527 							  len - i - 1);
528 			break;
529 		case 0x0012:
530 			if ((len > 4) && dell_privacy_process_event(le16_to_cpu(buffer_entry[1]),
531 								    le16_to_cpu(buffer_entry[3]),
532 								    le16_to_cpu(buffer_entry[4])))
533 				/* dell_privacy_process_event has handled the event */;
534 			else if (len > 2)
535 				dell_wmi_process_key(wdev, le16_to_cpu(buffer_entry[1]),
536 						     le16_to_cpu(buffer_entry[2]),
537 						     buffer_entry + 3, len - 3);
538 			break;
539 		default: /* Unknown event */
540 			pr_info("Unknown WMI event type 0x%x\n", le16_to_cpu(buffer_entry[1]));
541 			break;
542 		}
543 
544 		buffer_entry += len;
545 
546 	}
547 
548 }
549 
have_scancode(u32 scancode,const struct key_entry * keymap,int len)550 static bool have_scancode(u32 scancode, const struct key_entry *keymap, int len)
551 {
552 	int i;
553 
554 	for (i = 0; i < len; i++)
555 		if (keymap[i].code == scancode)
556 			return true;
557 
558 	return false;
559 }
560 
handle_dmi_entry(const struct dmi_header * dm,void * opaque)561 static void handle_dmi_entry(const struct dmi_header *dm, void *opaque)
562 {
563 	struct dell_dmi_results *results = opaque;
564 	struct dell_bios_hotkey_table *table;
565 	int hotkey_num, i, pos = 0;
566 	struct key_entry *keymap;
567 
568 	if (results->err || results->keymap)
569 		return;		/* We already found the hotkey table. */
570 
571 	/* The Dell hotkey table is type 0xB2.  Scan until we find it. */
572 	if (dm->type != 0xb2)
573 		return;
574 
575 	table = container_of(dm, struct dell_bios_hotkey_table, header);
576 
577 	hotkey_num = (table->header.length -
578 		      sizeof(struct dell_bios_hotkey_table)) /
579 				sizeof(struct dell_bios_keymap_entry);
580 	if (hotkey_num < 1) {
581 		/*
582 		 * Historically, dell-wmi would ignore a DMI entry of
583 		 * fewer than 7 bytes.  Sizes between 4 and 8 bytes are
584 		 * nonsensical (both the header and all entries are 4
585 		 * bytes), so we approximate the old behavior by
586 		 * ignoring tables with fewer than one entry.
587 		 */
588 		return;
589 	}
590 
591 	keymap = kzalloc_objs(struct key_entry, hotkey_num);
592 	if (!keymap) {
593 		results->err = -ENOMEM;
594 		return;
595 	}
596 
597 	for (i = 0; i < hotkey_num; i++) {
598 		const struct dell_bios_keymap_entry *bios_entry =
599 					&table->keymap[i];
600 
601 		/* Uninitialized entries are 0 aka KEY_RESERVED. */
602 		u16 keycode = (bios_entry->keycode <
603 			       ARRAY_SIZE(bios_to_linux_keycode)) ?
604 			bios_to_linux_keycode[bios_entry->keycode] :
605 			(bios_entry->keycode == 0xffff ? KEY_UNKNOWN : KEY_RESERVED);
606 
607 		/*
608 		 * Log if we find an entry in the DMI table that we don't
609 		 * understand.  If this happens, we should figure out what
610 		 * the entry means and add it to bios_to_linux_keycode.
611 		 */
612 		if (keycode == KEY_RESERVED) {
613 			pr_info("firmware scancode 0x%x maps to unrecognized keycode 0x%x\n",
614 				bios_entry->scancode, bios_entry->keycode);
615 			continue;
616 		}
617 
618 		if (keycode == KEY_KBDILLUMTOGGLE)
619 			keymap[pos].type = KE_IGNORE;
620 		else
621 			keymap[pos].type = KE_KEY;
622 		keymap[pos].code = bios_entry->scancode;
623 		keymap[pos].keycode = keycode;
624 
625 		pos++;
626 	}
627 
628 	results->keymap = keymap;
629 	results->keymap_size = pos;
630 }
631 
dell_wmi_input_setup(struct wmi_device * wdev)632 static int dell_wmi_input_setup(struct wmi_device *wdev)
633 {
634 	struct dell_wmi_priv *priv = dev_get_drvdata(&wdev->dev);
635 	struct dell_dmi_results dmi_results = {};
636 	struct key_entry *keymap;
637 	int err, i, pos = 0;
638 
639 	priv->input_dev = input_allocate_device();
640 	if (!priv->input_dev)
641 		return -ENOMEM;
642 
643 	priv->input_dev->name = "Dell WMI hotkeys";
644 	priv->input_dev->id.bustype = BUS_HOST;
645 	priv->input_dev->dev.parent = &wdev->dev;
646 
647 	if (dmi_walk(handle_dmi_entry, &dmi_results)) {
648 		/*
649 		 * Historically, dell-wmi ignored dmi_walk errors.  A failure
650 		 * is certainly surprising, but it probably just indicates
651 		 * a very old laptop.
652 		 */
653 		pr_warn("no DMI; using the old-style hotkey interface\n");
654 	}
655 
656 	if (dmi_results.err) {
657 		err = dmi_results.err;
658 		goto err_free_dev;
659 	}
660 
661 	keymap = kzalloc_objs(struct key_entry,
662 			      dmi_results.keymap_size + ARRAY_SIZE(dell_wmi_keymap_type_0000) + ARRAY_SIZE(dell_wmi_keymap_type_0010) + ARRAY_SIZE(dell_wmi_keymap_type_0011) + ARRAY_SIZE(dell_wmi_keymap_type_0012) + 1);
663 	if (!keymap) {
664 		kfree(dmi_results.keymap);
665 		err = -ENOMEM;
666 		goto err_free_dev;
667 	}
668 
669 	/* Append table with events of type 0x0010 which comes from DMI */
670 	for (i = 0; i < dmi_results.keymap_size; i++) {
671 		keymap[pos] = dmi_results.keymap[i];
672 		keymap[pos].code |= (0x0010 << 16);
673 		pos++;
674 	}
675 
676 	kfree(dmi_results.keymap);
677 
678 	/* Append table with extra events of type 0x0010 which are not in DMI */
679 	for (i = 0; i < ARRAY_SIZE(dell_wmi_keymap_type_0010); i++) {
680 		const struct key_entry *entry = &dell_wmi_keymap_type_0010[i];
681 
682 		/*
683 		 * Check if we've already found this scancode.  This takes
684 		 * quadratic time, but it doesn't matter unless the list
685 		 * of extra keys gets very long.
686 		 */
687 		if (dmi_results.keymap_size &&
688 		    have_scancode(entry->code | (0x0010 << 16),
689 				  keymap, dmi_results.keymap_size)
690 		   )
691 			continue;
692 
693 		keymap[pos] = *entry;
694 		keymap[pos].code |= (0x0010 << 16);
695 		pos++;
696 	}
697 
698 	/* Append table with events of type 0x0011 */
699 	for (i = 0; i < ARRAY_SIZE(dell_wmi_keymap_type_0011); i++) {
700 		keymap[pos] = dell_wmi_keymap_type_0011[i];
701 		keymap[pos].code |= (0x0011 << 16);
702 		pos++;
703 	}
704 
705 	/* Append table with events of type 0x0012 */
706 	for (i = 0; i < ARRAY_SIZE(dell_wmi_keymap_type_0012); i++) {
707 		keymap[pos] = dell_wmi_keymap_type_0012[i];
708 		keymap[pos].code |= (0x0012 << 16);
709 		pos++;
710 	}
711 
712 	/*
713 	 * Now append also table with "legacy" events of type 0x0000. Some of
714 	 * them are reported also on laptops which have scancodes in DMI.
715 	 */
716 	for (i = 0; i < ARRAY_SIZE(dell_wmi_keymap_type_0000); i++) {
717 		keymap[pos] = dell_wmi_keymap_type_0000[i];
718 		pos++;
719 	}
720 
721 	keymap[pos].type = KE_END;
722 
723 	err = sparse_keymap_setup(priv->input_dev, keymap, NULL);
724 	/*
725 	 * Sparse keymap library makes a copy of keymap so we don't need the
726 	 * original one that was allocated.
727 	 */
728 	kfree(keymap);
729 	if (err)
730 		goto err_free_dev;
731 
732 	err = input_register_device(priv->input_dev);
733 	if (err)
734 		goto err_free_dev;
735 
736 	return 0;
737 
738  err_free_dev:
739 	input_free_device(priv->input_dev);
740 	return err;
741 }
742 
dell_wmi_input_destroy(struct wmi_device * wdev)743 static void dell_wmi_input_destroy(struct wmi_device *wdev)
744 {
745 	struct dell_wmi_priv *priv = dev_get_drvdata(&wdev->dev);
746 
747 	input_unregister_device(priv->input_dev);
748 	if (priv->tabletswitch_dev)
749 		input_unregister_device(priv->tabletswitch_dev);
750 }
751 
752 /*
753  * According to Dell SMBIOS documentation:
754  *
755  * 17  3  Application Program Registration
756  *
757  *     cbArg1 Application ID 1 = 0x00010000
758  *     cbArg2 Application ID 2
759  *            QUICKSET/DCP = 0x51534554 "QSET"
760  *            ALS Driver   = 0x416c7353 "AlsS"
761  *            Latitude ON  = 0x4c6f6e52 "LonR"
762  *     cbArg3 Application version or revision number
763  *     cbArg4 0 = Unregister application
764  *            1 = Register application
765  *     cbRes1 Standard return codes (0, -1, -2)
766  */
767 
dell_wmi_events_set_enabled(bool enable)768 static int dell_wmi_events_set_enabled(bool enable)
769 {
770 	struct calling_interface_buffer *buffer;
771 	int ret;
772 
773 	buffer = kzalloc_obj(struct calling_interface_buffer);
774 	if (!buffer)
775 		return -ENOMEM;
776 	buffer->cmd_class = CLASS_INFO;
777 	buffer->cmd_select = SELECT_APP_REGISTRATION;
778 	buffer->input[0] = 0x10000;
779 	buffer->input[1] = 0x51534554;
780 	buffer->input[3] = enable;
781 	ret = dell_smbios_call(buffer);
782 	if (ret == 0)
783 		ret = buffer->output[0];
784 	kfree(buffer);
785 
786 	return dell_smbios_error(ret);
787 }
788 
dell_wmi_probe(struct wmi_device * wdev,const void * context)789 static int dell_wmi_probe(struct wmi_device *wdev, const void *context)
790 {
791 	struct dell_wmi_priv *priv;
792 	int ret;
793 
794 	ret = dell_wmi_get_descriptor_valid();
795 	if (ret)
796 		return ret;
797 
798 	priv = devm_kzalloc(
799 		&wdev->dev, sizeof(struct dell_wmi_priv), GFP_KERNEL);
800 	if (!priv)
801 		return -ENOMEM;
802 	dev_set_drvdata(&wdev->dev, priv);
803 
804 	if (!dell_wmi_get_interface_version(&priv->interface_version))
805 		return -EPROBE_DEFER;
806 
807 	return dell_wmi_input_setup(wdev);
808 }
809 
dell_wmi_remove(struct wmi_device * wdev)810 static void dell_wmi_remove(struct wmi_device *wdev)
811 {
812 	dell_wmi_input_destroy(wdev);
813 }
814 static const struct wmi_device_id dell_wmi_id_table[] = {
815 	{ .guid_string = DELL_EVENT_GUID },
816 	{ },
817 };
818 
819 static struct wmi_driver dell_wmi_driver = {
820 	.driver = {
821 		.name = "dell-wmi",
822 	},
823 	.id_table = dell_wmi_id_table,
824 	.min_event_size = sizeof(__le16),
825 	.probe = dell_wmi_probe,
826 	.remove = dell_wmi_remove,
827 	.notify_new = dell_wmi_notify,
828 };
829 
dell_wmi_init(void)830 static int __init dell_wmi_init(void)
831 {
832 	int err;
833 
834 	dmi_check_system(dell_wmi_smbios_list);
835 
836 	if (wmi_requires_smbios_request) {
837 		err = dell_wmi_events_set_enabled(true);
838 		if (err) {
839 			pr_err("Failed to enable WMI events\n");
840 			return err;
841 		}
842 	}
843 
844 	err = dell_privacy_register_driver();
845 	if (err)
846 		goto out_smbios;
847 
848 	err = wmi_driver_register(&dell_wmi_driver);
849 	if (err)
850 		goto out_privacy;
851 
852 	return 0;
853 
854 out_privacy:
855 	dell_privacy_unregister_driver();
856 
857 out_smbios:
858 	if (wmi_requires_smbios_request)
859 		dell_wmi_events_set_enabled(false);
860 
861 	return err;
862 }
863 late_initcall(dell_wmi_init);
864 
dell_wmi_exit(void)865 static void __exit dell_wmi_exit(void)
866 {
867 	if (wmi_requires_smbios_request)
868 		dell_wmi_events_set_enabled(false);
869 
870 	wmi_driver_unregister(&dell_wmi_driver);
871 	dell_privacy_unregister_driver();
872 }
873 module_exit(dell_wmi_exit);
874 
875 MODULE_DEVICE_TABLE(wmi, dell_wmi_id_table);
876