xref: /linux/drivers/platform/x86/huawei-wmi.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  Huawei WMI laptop extras driver
4  *
5  *  Copyright (C) 2018	      Ayman Bagabas <ayman.bagabas@gmail.com>
6  */
7 
8 #include <linux/acpi.h>
9 #include <linux/debugfs.h>
10 #include <linux/delay.h>
11 #include <linux/dmi.h>
12 #include <linux/input.h>
13 #include <linux/input/sparse-keymap.h>
14 #include <linux/leds.h>
15 #include <linux/module.h>
16 #include <linux/mutex.h>
17 #include <linux/platform_device.h>
18 #include <linux/power_supply.h>
19 #include <linux/sysfs.h>
20 #include <linux/wmi.h>
21 #include <acpi/battery.h>
22 
23 /*
24  * Huawei WMI GUIDs
25  */
26 #define HWMI_METHOD_GUID "ABBC0F5B-8EA1-11D1-A000-C90629100000"
27 #define HWMI_EVENT_GUID "ABBC0F5C-8EA1-11D1-A000-C90629100000"
28 
29 /* Legacy GUIDs */
30 #define WMI0_EXPENSIVE_GUID "39142400-C6A3-40fa-BADB-8A2652834100"
31 #define WMI0_EVENT_GUID "59142400-C6A3-40fa-BADB-8A2652834100"
32 
33 /* HWMI commands */
34 
35 enum {
36 	BATTERY_THRESH_GET		= 0x00001103, /* \GBTT */
37 	BATTERY_THRESH_SET		= 0x00001003, /* \SBTT */
38 	FN_LOCK_GET			= 0x00000604, /* \GFRS */
39 	FN_LOCK_SET			= 0x00000704, /* \SFRS */
40 	MICMUTE_LED_SET			= 0x00000b04, /* \SMLS */
41 };
42 
43 union hwmi_arg {
44 	u64 cmd;
45 	u8 args[8];
46 };
47 
48 struct quirk_entry {
49 	bool battery_reset;
50 	bool ec_micmute;
51 	bool report_brightness;
52 };
53 
54 static struct quirk_entry *quirks;
55 
56 struct huawei_wmi_debug {
57 	struct dentry *root;
58 	u64 arg;
59 };
60 
61 struct huawei_wmi {
62 	bool battery_available;
63 	bool fn_lock_available;
64 
65 	struct huawei_wmi_debug debug;
66 	struct led_classdev cdev;
67 	struct device *dev;
68 
69 	struct mutex wmi_lock;
70 };
71 
72 static struct huawei_wmi *huawei_wmi;
73 
74 static const struct key_entry huawei_wmi_keymap[] = {
75 	{ KE_KEY,    0x281, { KEY_BRIGHTNESSDOWN } },
76 	{ KE_KEY,    0x282, { KEY_BRIGHTNESSUP } },
77 	{ KE_KEY,    0x284, { KEY_MUTE } },
78 	{ KE_KEY,    0x285, { KEY_VOLUMEDOWN } },
79 	{ KE_KEY,    0x286, { KEY_VOLUMEUP } },
80 	{ KE_KEY,    0x287, { KEY_MICMUTE } },
81 	{ KE_KEY,    0x289, { KEY_WLAN } },
82 	// Huawei |M| key
83 	{ KE_KEY,    0x28a, { KEY_CONFIG } },
84 	// Keyboard backlit
85 	{ KE_IGNORE, 0x293, { KEY_KBDILLUMTOGGLE } },
86 	{ KE_IGNORE, 0x294, { KEY_KBDILLUMUP } },
87 	{ KE_IGNORE, 0x295, { KEY_KBDILLUMUP } },
88 	// Ignore Ambient Light Sensoring
89 	{ KE_KEY,    0x2c1, { KEY_RESERVED } },
90 	{ KE_END,	 0 }
91 };
92 
93 static int battery_reset = -1;
94 static int report_brightness = -1;
95 
96 module_param(battery_reset, bint, 0444);
97 MODULE_PARM_DESC(battery_reset,
98 		"Reset battery charge values to (0-0) before disabling it using (0-100)");
99 module_param(report_brightness, bint, 0444);
100 MODULE_PARM_DESC(report_brightness,
101 		"Report brightness keys.");
102 
103 /* Quirks */
104 
105 static int __init dmi_matched(const struct dmi_system_id *dmi)
106 {
107 	quirks = dmi->driver_data;
108 	return 1;
109 }
110 
111 static struct quirk_entry quirk_unknown = {
112 };
113 
114 static struct quirk_entry quirk_battery_reset = {
115 	.battery_reset = true,
116 };
117 
118 static struct quirk_entry quirk_matebook_x = {
119 	.ec_micmute = true,
120 	.report_brightness = true,
121 };
122 
123 static const struct dmi_system_id huawei_quirks[] = {
124 	{
125 		.callback = dmi_matched,
126 		.ident = "Huawei MACH-WX9",
127 		.matches = {
128 			DMI_MATCH(DMI_SYS_VENDOR, "HUAWEI"),
129 			DMI_MATCH(DMI_PRODUCT_NAME, "MACH-WX9"),
130 		},
131 		.driver_data = &quirk_battery_reset
132 	},
133 	{
134 		.callback = dmi_matched,
135 		.ident = "Huawei MateBook X",
136 		.matches = {
137 			DMI_MATCH(DMI_SYS_VENDOR, "HUAWEI"),
138 			DMI_MATCH(DMI_PRODUCT_NAME, "HUAWEI MateBook X")
139 		},
140 		.driver_data = &quirk_matebook_x
141 	},
142 	{  }
143 };
144 
145 /* Utils */
146 
147 static int huawei_wmi_call(struct huawei_wmi *huawei,
148 			   struct acpi_buffer *in, struct acpi_buffer *out)
149 {
150 	acpi_status status;
151 
152 	mutex_lock(&huawei->wmi_lock);
153 	status = wmi_evaluate_method(HWMI_METHOD_GUID, 0, 1, in, out);
154 	mutex_unlock(&huawei->wmi_lock);
155 	if (ACPI_FAILURE(status)) {
156 		dev_err(huawei->dev, "Failed to evaluate wmi method\n");
157 		return -ENODEV;
158 	}
159 
160 	return 0;
161 }
162 
163 /* HWMI takes a 64 bit input and returns either a package with 2 buffers, one of
164  * 4 bytes and the other of 256 bytes, or one buffer of size 0x104 (260) bytes.
165  * The first 4 bytes are ignored, we ignore the first 4 bytes buffer if we got a
166  * package, or skip the first 4 if a buffer of 0x104 is used. The first byte of
167  * the remaining 0x100 sized buffer has the return status of every call. In case
168  * the return status is non-zero, we return -ENODEV but still copy the returned
169  * buffer to the given buffer parameter (buf).
170  */
171 static int huawei_wmi_cmd(u64 arg, u8 *buf, size_t buflen)
172 {
173 	struct huawei_wmi *huawei = huawei_wmi;
174 	struct acpi_buffer out = { ACPI_ALLOCATE_BUFFER, NULL };
175 	struct acpi_buffer in;
176 	union acpi_object *obj;
177 	size_t len;
178 	int err, i;
179 
180 	in.length = sizeof(arg);
181 	in.pointer = &arg;
182 
183 	/* Some models require calling HWMI twice to execute a command. We evaluate
184 	 * HWMI and if we get a non-zero return status we evaluate it again.
185 	 */
186 	for (i = 0; i < 2; i++) {
187 		err = huawei_wmi_call(huawei, &in, &out);
188 		if (err)
189 			goto fail_cmd;
190 
191 		obj = out.pointer;
192 		if (!obj) {
193 			err = -EIO;
194 			goto fail_cmd;
195 		}
196 
197 		switch (obj->type) {
198 		/* Models that implement both "legacy" and HWMI tend to return a 0x104
199 		 * sized buffer instead of a package of 0x4 and 0x100 buffers.
200 		 */
201 		case ACPI_TYPE_BUFFER:
202 			if (obj->buffer.length == 0x104) {
203 				// Skip the first 4 bytes.
204 				obj->buffer.pointer += 4;
205 				len = 0x100;
206 			} else {
207 				dev_err(huawei->dev, "Bad buffer length, got %d\n", obj->buffer.length);
208 				err = -EIO;
209 				goto fail_cmd;
210 			}
211 
212 			break;
213 		/* HWMI returns a package with 2 buffer elements, one of 4 bytes and the
214 		 * other is 256 bytes.
215 		 */
216 		case ACPI_TYPE_PACKAGE:
217 			if (obj->package.count != 2) {
218 				dev_err(huawei->dev, "Bad package count, got %d\n", obj->package.count);
219 				err = -EIO;
220 				goto fail_cmd;
221 			}
222 
223 			obj = &obj->package.elements[1];
224 			if (obj->type != ACPI_TYPE_BUFFER) {
225 				dev_err(huawei->dev, "Bad package element type, got %d\n", obj->type);
226 				err = -EIO;
227 				goto fail_cmd;
228 			}
229 			len = obj->buffer.length;
230 
231 			break;
232 		/* Shouldn't get here! */
233 		default:
234 			dev_err(huawei->dev, "Unexpected obj type, got: %d\n", obj->type);
235 			err = -EIO;
236 			goto fail_cmd;
237 		}
238 
239 		if (!*obj->buffer.pointer)
240 			break;
241 	}
242 
243 	err = (*obj->buffer.pointer) ? -ENODEV : 0;
244 
245 	if (buf) {
246 		len = min(buflen, len);
247 		memcpy(buf, obj->buffer.pointer, len);
248 	}
249 
250 fail_cmd:
251 	kfree(out.pointer);
252 	return err;
253 }
254 
255 /* LEDs */
256 
257 static int huawei_wmi_micmute_led_set(struct led_classdev *led_cdev,
258 		enum led_brightness brightness)
259 {
260 	/* This is a workaround until the "legacy" interface is implemented. */
261 	if (quirks && quirks->ec_micmute) {
262 		char *acpi_method;
263 		acpi_handle handle;
264 		acpi_status status;
265 		union acpi_object args[3];
266 		struct acpi_object_list arg_list = {
267 			.pointer = args,
268 			.count = ARRAY_SIZE(args),
269 		};
270 
271 		handle = ec_get_handle();
272 		if (!handle)
273 			return -ENODEV;
274 
275 		args[0].type = args[1].type = args[2].type = ACPI_TYPE_INTEGER;
276 		args[1].integer.value = 0x04;
277 
278 		if (acpi_has_method(handle, "SPIN")) {
279 			acpi_method = "SPIN";
280 			args[0].integer.value = 0;
281 			args[2].integer.value = brightness ? 1 : 0;
282 		} else if (acpi_has_method(handle, "WPIN")) {
283 			acpi_method = "WPIN";
284 			args[0].integer.value = 1;
285 			args[2].integer.value = brightness ? 0 : 1;
286 		} else {
287 			return -ENODEV;
288 		}
289 
290 		status = acpi_evaluate_object(handle, acpi_method, &arg_list, NULL);
291 		if (ACPI_FAILURE(status))
292 			return -ENODEV;
293 
294 		return 0;
295 	} else {
296 		union hwmi_arg arg;
297 
298 		arg.cmd = MICMUTE_LED_SET;
299 		arg.args[2] = brightness;
300 
301 		return huawei_wmi_cmd(arg.cmd, NULL, 0);
302 	}
303 }
304 
305 static void huawei_wmi_leds_setup(struct device *dev)
306 {
307 	struct huawei_wmi *huawei = dev_get_drvdata(dev);
308 
309 	huawei->cdev.name = "platform::micmute";
310 	huawei->cdev.max_brightness = 1;
311 	huawei->cdev.brightness_set_blocking = &huawei_wmi_micmute_led_set;
312 	huawei->cdev.default_trigger = "audio-micmute";
313 	huawei->cdev.dev = dev;
314 	huawei->cdev.flags = LED_CORE_SUSPENDRESUME;
315 
316 	devm_led_classdev_register(dev, &huawei->cdev);
317 }
318 
319 /* Battery protection */
320 
321 static int huawei_wmi_battery_get(int *start, int *end)
322 {
323 	u8 ret[0x100];
324 	int err, i;
325 
326 	err = huawei_wmi_cmd(BATTERY_THRESH_GET, ret, sizeof(ret));
327 	if (err)
328 		return err;
329 
330 	/* Find the last two non-zero values. Return status is ignored. */
331 	i = ARRAY_SIZE(ret) - 1;
332 	do {
333 		if (start)
334 			*start = ret[i-1];
335 		if (end)
336 			*end = ret[i];
337 	} while (i > 2 && !ret[i--]);
338 
339 	return 0;
340 }
341 
342 static int huawei_wmi_battery_set(int start, int end)
343 {
344 	union hwmi_arg arg;
345 	int err;
346 
347 	if (start < 0 || end < 0 || start > 100 || end > 100)
348 		return -EINVAL;
349 
350 	arg.cmd = BATTERY_THRESH_SET;
351 	arg.args[2] = start;
352 	arg.args[3] = end;
353 
354 	/* This is an edge case were some models turn battery protection
355 	 * off without changing their thresholds values. We clear the
356 	 * values before turning off protection. Sometimes we need a sleep delay to
357 	 * make sure these values make their way to EC memory.
358 	 */
359 	if (quirks && quirks->battery_reset && start == 0 && end == 100) {
360 		err = huawei_wmi_battery_set(0, 0);
361 		if (err)
362 			return err;
363 
364 		msleep(1000);
365 	}
366 
367 	err = huawei_wmi_cmd(arg.cmd, NULL, 0);
368 
369 	return err;
370 }
371 
372 static ssize_t charge_control_start_threshold_show(struct device *dev,
373 		struct device_attribute *attr,
374 		char *buf)
375 {
376 	int err, start;
377 
378 	err = huawei_wmi_battery_get(&start, NULL);
379 	if (err)
380 		return err;
381 
382 	return sysfs_emit(buf, "%d\n", start);
383 }
384 
385 static ssize_t charge_control_end_threshold_show(struct device *dev,
386 		struct device_attribute *attr,
387 		char *buf)
388 {
389 	int err, end;
390 
391 	err = huawei_wmi_battery_get(NULL, &end);
392 	if (err)
393 		return err;
394 
395 	return sysfs_emit(buf, "%d\n", end);
396 }
397 
398 static ssize_t charge_control_thresholds_show(struct device *dev,
399 		struct device_attribute *attr,
400 		char *buf)
401 {
402 	int err, start, end;
403 
404 	err = huawei_wmi_battery_get(&start, &end);
405 	if (err)
406 		return err;
407 
408 	return sysfs_emit(buf, "%d %d\n", start, end);
409 }
410 
411 static ssize_t charge_control_start_threshold_store(struct device *dev,
412 		struct device_attribute *attr,
413 		const char *buf, size_t size)
414 {
415 	int err, start, end;
416 
417 	err = huawei_wmi_battery_get(NULL, &end);
418 	if (err)
419 		return err;
420 
421 	if (sscanf(buf, "%d", &start) != 1)
422 		return -EINVAL;
423 
424 	err = huawei_wmi_battery_set(start, end);
425 	if (err)
426 		return err;
427 
428 	return size;
429 }
430 
431 static ssize_t charge_control_end_threshold_store(struct device *dev,
432 		struct device_attribute *attr,
433 		const char *buf, size_t size)
434 {
435 	int err, start, end;
436 
437 	err = huawei_wmi_battery_get(&start, NULL);
438 	if (err)
439 		return err;
440 
441 	if (sscanf(buf, "%d", &end) != 1)
442 		return -EINVAL;
443 
444 	err = huawei_wmi_battery_set(start, end);
445 	if (err)
446 		return err;
447 
448 	return size;
449 }
450 
451 static ssize_t charge_control_thresholds_store(struct device *dev,
452 		struct device_attribute *attr,
453 		const char *buf, size_t size)
454 {
455 	int err, start, end;
456 
457 	if (sscanf(buf, "%d %d", &start, &end) != 2)
458 		return -EINVAL;
459 
460 	err = huawei_wmi_battery_set(start, end);
461 	if (err)
462 		return err;
463 
464 	return size;
465 }
466 
467 static DEVICE_ATTR_RW(charge_control_start_threshold);
468 static DEVICE_ATTR_RW(charge_control_end_threshold);
469 static DEVICE_ATTR_RW(charge_control_thresholds);
470 
471 static int huawei_wmi_battery_add(struct power_supply *battery, struct acpi_battery_hook *hook)
472 {
473 	int err = 0;
474 
475 	err = device_create_file(&battery->dev, &dev_attr_charge_control_start_threshold);
476 	if (err)
477 		return err;
478 
479 	err = device_create_file(&battery->dev, &dev_attr_charge_control_end_threshold);
480 	if (err)
481 		device_remove_file(&battery->dev, &dev_attr_charge_control_start_threshold);
482 
483 	return err;
484 }
485 
486 static int huawei_wmi_battery_remove(struct power_supply *battery, struct acpi_battery_hook *hook)
487 {
488 	device_remove_file(&battery->dev, &dev_attr_charge_control_start_threshold);
489 	device_remove_file(&battery->dev, &dev_attr_charge_control_end_threshold);
490 
491 	return 0;
492 }
493 
494 static struct acpi_battery_hook huawei_wmi_battery_hook = {
495 	.add_battery = huawei_wmi_battery_add,
496 	.remove_battery = huawei_wmi_battery_remove,
497 	.name = "Huawei Battery Extension"
498 };
499 
500 static void huawei_wmi_battery_setup(struct device *dev)
501 {
502 	struct huawei_wmi *huawei = dev_get_drvdata(dev);
503 
504 	huawei->battery_available = true;
505 	if (huawei_wmi_battery_get(NULL, NULL)) {
506 		huawei->battery_available = false;
507 		return;
508 	}
509 
510 	battery_hook_register(&huawei_wmi_battery_hook);
511 	device_create_file(dev, &dev_attr_charge_control_thresholds);
512 }
513 
514 static void huawei_wmi_battery_exit(struct device *dev)
515 {
516 	struct huawei_wmi *huawei = dev_get_drvdata(dev);
517 
518 	if (huawei->battery_available) {
519 		battery_hook_unregister(&huawei_wmi_battery_hook);
520 		device_remove_file(dev, &dev_attr_charge_control_thresholds);
521 	}
522 }
523 
524 /* Fn lock */
525 
526 static int huawei_wmi_fn_lock_get(int *on)
527 {
528 	u8 ret[0x100] = { 0 };
529 	int err, i;
530 
531 	err = huawei_wmi_cmd(FN_LOCK_GET, ret, 0x100);
532 	if (err)
533 		return err;
534 
535 	/* Find the first non-zero value. Return status is ignored. */
536 	i = 1;
537 	do {
538 		if (on)
539 			*on = ret[i] - 1; // -1 undefined, 0 off, 1 on.
540 	} while (i < 0xff && !ret[i++]);
541 
542 	return 0;
543 }
544 
545 static int huawei_wmi_fn_lock_set(int on)
546 {
547 	union hwmi_arg arg;
548 
549 	arg.cmd = FN_LOCK_SET;
550 	arg.args[2] = on + 1; // 0 undefined, 1 off, 2 on.
551 
552 	return huawei_wmi_cmd(arg.cmd, NULL, 0);
553 }
554 
555 static ssize_t fn_lock_state_show(struct device *dev,
556 		struct device_attribute *attr,
557 		char *buf)
558 {
559 	int err, on;
560 
561 	err = huawei_wmi_fn_lock_get(&on);
562 	if (err)
563 		return err;
564 
565 	return sysfs_emit(buf, "%d\n", on);
566 }
567 
568 static ssize_t fn_lock_state_store(struct device *dev,
569 		struct device_attribute *attr,
570 		const char *buf, size_t size)
571 {
572 	int on, err;
573 
574 	if (kstrtoint(buf, 10, &on) ||
575 			on < 0 || on > 1)
576 		return -EINVAL;
577 
578 	err = huawei_wmi_fn_lock_set(on);
579 	if (err)
580 		return err;
581 
582 	return size;
583 }
584 
585 static DEVICE_ATTR_RW(fn_lock_state);
586 
587 static void huawei_wmi_fn_lock_setup(struct device *dev)
588 {
589 	struct huawei_wmi *huawei = dev_get_drvdata(dev);
590 
591 	huawei->fn_lock_available = true;
592 	if (huawei_wmi_fn_lock_get(NULL)) {
593 		huawei->fn_lock_available = false;
594 		return;
595 	}
596 
597 	device_create_file(dev, &dev_attr_fn_lock_state);
598 }
599 
600 static void huawei_wmi_fn_lock_exit(struct device *dev)
601 {
602 	struct huawei_wmi *huawei = dev_get_drvdata(dev);
603 
604 	if (huawei->fn_lock_available)
605 		device_remove_file(dev, &dev_attr_fn_lock_state);
606 }
607 
608 /* debugfs */
609 
610 static void huawei_wmi_debugfs_call_dump(struct seq_file *m, void *data,
611 		union acpi_object *obj)
612 {
613 	struct huawei_wmi *huawei = m->private;
614 	int i;
615 
616 	switch (obj->type) {
617 	case ACPI_TYPE_INTEGER:
618 		seq_printf(m, "0x%llx", obj->integer.value);
619 		break;
620 	case ACPI_TYPE_STRING:
621 		seq_printf(m, "\"%.*s\"", obj->string.length, obj->string.pointer);
622 		break;
623 	case ACPI_TYPE_BUFFER:
624 		seq_puts(m, "{");
625 		for (i = 0; i < obj->buffer.length; i++) {
626 			seq_printf(m, "0x%02x", obj->buffer.pointer[i]);
627 			if (i < obj->buffer.length - 1)
628 				seq_puts(m, ",");
629 		}
630 		seq_puts(m, "}");
631 		break;
632 	case ACPI_TYPE_PACKAGE:
633 		seq_puts(m, "[");
634 		for (i = 0; i < obj->package.count; i++) {
635 			huawei_wmi_debugfs_call_dump(m, huawei, &obj->package.elements[i]);
636 			if (i < obj->package.count - 1)
637 				seq_puts(m, ",");
638 		}
639 		seq_puts(m, "]");
640 		break;
641 	default:
642 		dev_err(huawei->dev, "Unexpected obj type, got %d\n", obj->type);
643 		return;
644 	}
645 }
646 
647 static int huawei_wmi_debugfs_call_show(struct seq_file *m, void *data)
648 {
649 	struct huawei_wmi *huawei = m->private;
650 	struct acpi_buffer out = { ACPI_ALLOCATE_BUFFER, NULL };
651 	struct acpi_buffer in;
652 	union acpi_object *obj;
653 	int err;
654 
655 	in.length = sizeof(u64);
656 	in.pointer = &huawei->debug.arg;
657 
658 	err = huawei_wmi_call(huawei, &in, &out);
659 	if (err)
660 		return err;
661 
662 	obj = out.pointer;
663 	if (!obj) {
664 		err = -EIO;
665 		goto fail_debugfs_call;
666 	}
667 
668 	huawei_wmi_debugfs_call_dump(m, huawei, obj);
669 
670 fail_debugfs_call:
671 	kfree(out.pointer);
672 	return err;
673 }
674 
675 DEFINE_SHOW_ATTRIBUTE(huawei_wmi_debugfs_call);
676 
677 static void huawei_wmi_debugfs_setup(struct device *dev)
678 {
679 	struct huawei_wmi *huawei = dev_get_drvdata(dev);
680 
681 	huawei->debug.root = debugfs_create_dir("huawei-wmi", NULL);
682 
683 	debugfs_create_x64("arg", 0644, huawei->debug.root,
684 		&huawei->debug.arg);
685 	debugfs_create_file("call", 0400,
686 		huawei->debug.root, huawei, &huawei_wmi_debugfs_call_fops);
687 }
688 
689 static void huawei_wmi_debugfs_exit(struct device *dev)
690 {
691 	struct huawei_wmi *huawei = dev_get_drvdata(dev);
692 
693 	debugfs_remove_recursive(huawei->debug.root);
694 }
695 
696 /* Input */
697 
698 static void huawei_wmi_process_key(struct input_dev *idev, int code)
699 {
700 	const struct key_entry *key;
701 
702 	/*
703 	 * WMI0 uses code 0x80 to indicate a hotkey event.
704 	 * The actual key is fetched from the method WQ00
705 	 * using WMI0_EXPENSIVE_GUID.
706 	 */
707 	if (code == 0x80) {
708 		struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
709 		union acpi_object *obj;
710 		acpi_status status;
711 
712 		status = wmi_query_block(WMI0_EXPENSIVE_GUID, 0, &response);
713 		if (ACPI_FAILURE(status))
714 			return;
715 
716 		obj = (union acpi_object *)response.pointer;
717 		if (obj && obj->type == ACPI_TYPE_INTEGER)
718 			code = obj->integer.value;
719 
720 		kfree(response.pointer);
721 	}
722 
723 	key = sparse_keymap_entry_from_scancode(idev, code);
724 	if (!key) {
725 		dev_info(&idev->dev, "Unknown key pressed, code: 0x%04x\n", code);
726 		return;
727 	}
728 
729 	if (quirks && !quirks->report_brightness &&
730 			(key->sw.code == KEY_BRIGHTNESSDOWN ||
731 			key->sw.code == KEY_BRIGHTNESSUP))
732 		return;
733 
734 	sparse_keymap_report_entry(idev, key, 1, true);
735 }
736 
737 static void huawei_wmi_input_notify(union acpi_object *obj, void *context)
738 {
739 	struct input_dev *idev = (struct input_dev *)context;
740 
741 	if (obj && obj->type == ACPI_TYPE_INTEGER)
742 		huawei_wmi_process_key(idev, obj->integer.value);
743 	else
744 		dev_err(&idev->dev, "Bad response type\n");
745 }
746 
747 static int huawei_wmi_input_setup(struct device *dev, const char *guid)
748 {
749 	struct input_dev *idev;
750 	acpi_status status;
751 	int err;
752 
753 	idev = devm_input_allocate_device(dev);
754 	if (!idev)
755 		return -ENOMEM;
756 
757 	idev->name = "Huawei WMI hotkeys";
758 	idev->phys = "wmi/input0";
759 	idev->id.bustype = BUS_HOST;
760 	idev->dev.parent = dev;
761 
762 	err = sparse_keymap_setup(idev, huawei_wmi_keymap, NULL);
763 	if (err)
764 		return err;
765 
766 	err = input_register_device(idev);
767 	if (err)
768 		return err;
769 
770 	status = wmi_install_notify_handler(guid, huawei_wmi_input_notify, idev);
771 	if (ACPI_FAILURE(status))
772 		return -EIO;
773 
774 	return 0;
775 }
776 
777 static void huawei_wmi_input_exit(struct device *dev, const char *guid)
778 {
779 	wmi_remove_notify_handler(guid);
780 }
781 
782 /* Huawei driver */
783 
784 static const struct wmi_device_id huawei_wmi_events_id_table[] = {
785 	{ .guid_string = WMI0_EVENT_GUID },
786 	{ .guid_string = HWMI_EVENT_GUID },
787 	{  }
788 };
789 
790 static int huawei_wmi_probe(struct platform_device *pdev)
791 {
792 	const struct wmi_device_id *guid = huawei_wmi_events_id_table;
793 	int err;
794 
795 	platform_set_drvdata(pdev, huawei_wmi);
796 	huawei_wmi->dev = &pdev->dev;
797 
798 	while (*guid->guid_string) {
799 		if (wmi_has_guid(guid->guid_string)) {
800 			err = huawei_wmi_input_setup(&pdev->dev, guid->guid_string);
801 			if (err) {
802 				dev_err(&pdev->dev, "Failed to setup input on %s\n", guid->guid_string);
803 				return err;
804 			}
805 		}
806 
807 		guid++;
808 	}
809 
810 	if (wmi_has_guid(HWMI_METHOD_GUID)) {
811 		mutex_init(&huawei_wmi->wmi_lock);
812 
813 		huawei_wmi_leds_setup(&pdev->dev);
814 		huawei_wmi_fn_lock_setup(&pdev->dev);
815 		huawei_wmi_battery_setup(&pdev->dev);
816 		huawei_wmi_debugfs_setup(&pdev->dev);
817 	}
818 
819 	return 0;
820 }
821 
822 static void huawei_wmi_remove(struct platform_device *pdev)
823 {
824 	const struct wmi_device_id *guid = huawei_wmi_events_id_table;
825 
826 	while (*guid->guid_string) {
827 		if (wmi_has_guid(guid->guid_string))
828 			huawei_wmi_input_exit(&pdev->dev, guid->guid_string);
829 
830 		guid++;
831 	}
832 
833 	if (wmi_has_guid(HWMI_METHOD_GUID)) {
834 		huawei_wmi_debugfs_exit(&pdev->dev);
835 		huawei_wmi_battery_exit(&pdev->dev);
836 		huawei_wmi_fn_lock_exit(&pdev->dev);
837 	}
838 }
839 
840 static struct platform_driver huawei_wmi_driver = {
841 	.driver = {
842 		.name = "huawei-wmi",
843 	},
844 	.probe = huawei_wmi_probe,
845 	.remove = huawei_wmi_remove,
846 };
847 
848 static __init int huawei_wmi_init(void)
849 {
850 	struct platform_device *pdev;
851 	int err;
852 
853 	huawei_wmi = kzalloc(sizeof(struct huawei_wmi), GFP_KERNEL);
854 	if (!huawei_wmi)
855 		return -ENOMEM;
856 
857 	quirks = &quirk_unknown;
858 	dmi_check_system(huawei_quirks);
859 	if (battery_reset != -1)
860 		quirks->battery_reset = battery_reset;
861 	if (report_brightness != -1)
862 		quirks->report_brightness = report_brightness;
863 
864 	err = platform_driver_register(&huawei_wmi_driver);
865 	if (err)
866 		goto pdrv_err;
867 
868 	pdev = platform_device_register_simple("huawei-wmi", PLATFORM_DEVID_NONE, NULL, 0);
869 	if (IS_ERR(pdev)) {
870 		err = PTR_ERR(pdev);
871 		goto pdev_err;
872 	}
873 
874 	return 0;
875 
876 pdev_err:
877 	platform_driver_unregister(&huawei_wmi_driver);
878 pdrv_err:
879 	kfree(huawei_wmi);
880 	return err;
881 }
882 
883 static __exit void huawei_wmi_exit(void)
884 {
885 	struct platform_device *pdev = to_platform_device(huawei_wmi->dev);
886 
887 	platform_device_unregister(pdev);
888 	platform_driver_unregister(&huawei_wmi_driver);
889 
890 	kfree(huawei_wmi);
891 }
892 
893 module_init(huawei_wmi_init);
894 module_exit(huawei_wmi_exit);
895 
896 MODULE_ALIAS("wmi:"HWMI_METHOD_GUID);
897 MODULE_DEVICE_TABLE(wmi, huawei_wmi_events_id_table);
898 MODULE_AUTHOR("Ayman Bagabas <ayman.bagabas@gmail.com>");
899 MODULE_DESCRIPTION("Huawei WMI laptop extras driver");
900 MODULE_LICENSE("GPL v2");
901