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 input_dev *idev[2];
67 	struct led_classdev cdev;
68 	struct device *dev;
69 
70 	struct mutex wmi_lock;
71 };
72 
73 static struct huawei_wmi *huawei_wmi;
74 
75 static const struct key_entry huawei_wmi_keymap[] = {
76 	{ KE_KEY,    0x281, { KEY_BRIGHTNESSDOWN } },
77 	{ KE_KEY,    0x282, { KEY_BRIGHTNESSUP } },
78 	{ KE_KEY,    0x284, { KEY_MUTE } },
79 	{ KE_KEY,    0x285, { KEY_VOLUMEDOWN } },
80 	{ KE_KEY,    0x286, { KEY_VOLUMEUP } },
81 	{ KE_KEY,    0x287, { KEY_MICMUTE } },
82 	{ KE_KEY,    0x289, { KEY_WLAN } },
83 	// Huawei |M| key
84 	{ KE_KEY,    0x28a, { KEY_CONFIG } },
85 	// Keyboard backlit
86 	{ KE_IGNORE, 0x293, { KEY_KBDILLUMTOGGLE } },
87 	{ KE_IGNORE, 0x294, { KEY_KBDILLUMUP } },
88 	{ KE_IGNORE, 0x295, { KEY_KBDILLUMUP } },
89 	{ KE_END,	 0 }
90 };
91 
92 static int battery_reset = -1;
93 static int report_brightness = -1;
94 
95 module_param(battery_reset, bint, 0444);
96 MODULE_PARM_DESC(battery_reset,
97 		"Reset battery charge values to (0-0) before disabling it using (0-100)");
98 module_param(report_brightness, bint, 0444);
99 MODULE_PARM_DESC(report_brightness,
100 		"Report brightness keys.");
101 
102 /* Quirks */
103 
104 static int __init dmi_matched(const struct dmi_system_id *dmi)
105 {
106 	quirks = dmi->driver_data;
107 	return 1;
108 }
109 
110 static struct quirk_entry quirk_unknown = {
111 };
112 
113 static struct quirk_entry quirk_battery_reset = {
114 	.battery_reset = true,
115 };
116 
117 static struct quirk_entry quirk_matebook_x = {
118 	.ec_micmute = true,
119 	.report_brightness = true,
120 };
121 
122 static const struct dmi_system_id huawei_quirks[] = {
123 	{
124 		.callback = dmi_matched,
125 		.ident = "Huawei MACH-WX9",
126 		.matches = {
127 			DMI_MATCH(DMI_SYS_VENDOR, "HUAWEI"),
128 			DMI_MATCH(DMI_PRODUCT_NAME, "MACH-WX9"),
129 		},
130 		.driver_data = &quirk_battery_reset
131 	},
132 	{
133 		.callback = dmi_matched,
134 		.ident = "Huawei MateBook X",
135 		.matches = {
136 			DMI_MATCH(DMI_SYS_VENDOR, "HUAWEI"),
137 			DMI_MATCH(DMI_PRODUCT_NAME, "HUAWEI MateBook X")
138 		},
139 		.driver_data = &quirk_matebook_x
140 	},
141 	{  }
142 };
143 
144 /* Utils */
145 
146 static int huawei_wmi_call(struct huawei_wmi *huawei,
147 			   struct acpi_buffer *in, struct acpi_buffer *out)
148 {
149 	acpi_status status;
150 
151 	mutex_lock(&huawei->wmi_lock);
152 	status = wmi_evaluate_method(HWMI_METHOD_GUID, 0, 1, in, out);
153 	mutex_unlock(&huawei->wmi_lock);
154 	if (ACPI_FAILURE(status)) {
155 		dev_err(huawei->dev, "Failed to evaluate wmi method\n");
156 		return -ENODEV;
157 	}
158 
159 	return 0;
160 }
161 
162 /* HWMI takes a 64 bit input and returns either a package with 2 buffers, one of
163  * 4 bytes and the other of 256 bytes, or one buffer of size 0x104 (260) bytes.
164  * The first 4 bytes are ignored, we ignore the first 4 bytes buffer if we got a
165  * package, or skip the first 4 if a buffer of 0x104 is used. The first byte of
166  * the remaining 0x100 sized buffer has the return status of every call. In case
167  * the return status is non-zero, we return -ENODEV but still copy the returned
168  * buffer to the given buffer parameter (buf).
169  */
170 static int huawei_wmi_cmd(u64 arg, u8 *buf, size_t buflen)
171 {
172 	struct huawei_wmi *huawei = huawei_wmi;
173 	struct acpi_buffer out = { ACPI_ALLOCATE_BUFFER, NULL };
174 	struct acpi_buffer in;
175 	union acpi_object *obj;
176 	size_t len;
177 	int err, i;
178 
179 	in.length = sizeof(arg);
180 	in.pointer = &arg;
181 
182 	/* Some models require calling HWMI twice to execute a command. We evaluate
183 	 * HWMI and if we get a non-zero return status we evaluate it again.
184 	 */
185 	for (i = 0; i < 2; i++) {
186 		err = huawei_wmi_call(huawei, &in, &out);
187 		if (err)
188 			goto fail_cmd;
189 
190 		obj = out.pointer;
191 		if (!obj) {
192 			err = -EIO;
193 			goto fail_cmd;
194 		}
195 
196 		switch (obj->type) {
197 		/* Models that implement both "legacy" and HWMI tend to return a 0x104
198 		 * sized buffer instead of a package of 0x4 and 0x100 buffers.
199 		 */
200 		case ACPI_TYPE_BUFFER:
201 			if (obj->buffer.length == 0x104) {
202 				// Skip the first 4 bytes.
203 				obj->buffer.pointer += 4;
204 				len = 0x100;
205 			} else {
206 				dev_err(huawei->dev, "Bad buffer length, got %d\n", obj->buffer.length);
207 				err = -EIO;
208 				goto fail_cmd;
209 			}
210 
211 			break;
212 		/* HWMI returns a package with 2 buffer elements, one of 4 bytes and the
213 		 * other is 256 bytes.
214 		 */
215 		case ACPI_TYPE_PACKAGE:
216 			if (obj->package.count != 2) {
217 				dev_err(huawei->dev, "Bad package count, got %d\n", obj->package.count);
218 				err = -EIO;
219 				goto fail_cmd;
220 			}
221 
222 			obj = &obj->package.elements[1];
223 			if (obj->type != ACPI_TYPE_BUFFER) {
224 				dev_err(huawei->dev, "Bad package element type, got %d\n", obj->type);
225 				err = -EIO;
226 				goto fail_cmd;
227 			}
228 			len = obj->buffer.length;
229 
230 			break;
231 		/* Shouldn't get here! */
232 		default:
233 			dev_err(huawei->dev, "Unexpected obj type, got: %d\n", obj->type);
234 			err = -EIO;
235 			goto fail_cmd;
236 		}
237 
238 		if (!*obj->buffer.pointer)
239 			break;
240 	}
241 
242 	err = (*obj->buffer.pointer) ? -ENODEV : 0;
243 
244 	if (buf) {
245 		len = min(buflen, len);
246 		memcpy(buf, obj->buffer.pointer, len);
247 	}
248 
249 fail_cmd:
250 	kfree(out.pointer);
251 	return err;
252 }
253 
254 /* LEDs */
255 
256 static int huawei_wmi_micmute_led_set(struct led_classdev *led_cdev,
257 		enum led_brightness brightness)
258 {
259 	/* This is a workaround until the "legacy" interface is implemented. */
260 	if (quirks && quirks->ec_micmute) {
261 		char *acpi_method;
262 		acpi_handle handle;
263 		acpi_status status;
264 		union acpi_object args[3];
265 		struct acpi_object_list arg_list = {
266 			.pointer = args,
267 			.count = ARRAY_SIZE(args),
268 		};
269 
270 		handle = ec_get_handle();
271 		if (!handle)
272 			return -ENODEV;
273 
274 		args[0].type = args[1].type = args[2].type = ACPI_TYPE_INTEGER;
275 		args[1].integer.value = 0x04;
276 
277 		if (acpi_has_method(handle, "SPIN")) {
278 			acpi_method = "SPIN";
279 			args[0].integer.value = 0;
280 			args[2].integer.value = brightness ? 1 : 0;
281 		} else if (acpi_has_method(handle, "WPIN")) {
282 			acpi_method = "WPIN";
283 			args[0].integer.value = 1;
284 			args[2].integer.value = brightness ? 0 : 1;
285 		} else {
286 			return -ENODEV;
287 		}
288 
289 		status = acpi_evaluate_object(handle, acpi_method, &arg_list, NULL);
290 		if (ACPI_FAILURE(status))
291 			return -ENODEV;
292 
293 		return 0;
294 	} else {
295 		union hwmi_arg arg;
296 
297 		arg.cmd = MICMUTE_LED_SET;
298 		arg.args[2] = brightness;
299 
300 		return huawei_wmi_cmd(arg.cmd, NULL, 0);
301 	}
302 }
303 
304 static void huawei_wmi_leds_setup(struct device *dev)
305 {
306 	struct huawei_wmi *huawei = dev_get_drvdata(dev);
307 
308 	huawei->cdev.name = "platform::micmute";
309 	huawei->cdev.max_brightness = 1;
310 	huawei->cdev.brightness_set_blocking = &huawei_wmi_micmute_led_set;
311 	huawei->cdev.default_trigger = "audio-micmute";
312 	huawei->cdev.brightness = ledtrig_audio_get(LED_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, 0x100);
327 	if (err)
328 		return err;
329 
330 	/* Find the last two non-zero values. Return status is ignored. */
331 	i = 0xff;
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 sprintf(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 sprintf(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 sprintf(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)
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)
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 sprintf(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(u32 value, void *context)
738 {
739 	struct input_dev *idev = (struct input_dev *)context;
740 	struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
741 	union acpi_object *obj;
742 	acpi_status status;
743 
744 	status = wmi_get_event_data(value, &response);
745 	if (ACPI_FAILURE(status)) {
746 		dev_err(&idev->dev, "Unable to get event data\n");
747 		return;
748 	}
749 
750 	obj = (union acpi_object *)response.pointer;
751 	if (obj && obj->type == ACPI_TYPE_INTEGER)
752 		huawei_wmi_process_key(idev, obj->integer.value);
753 	else
754 		dev_err(&idev->dev, "Bad response type\n");
755 
756 	kfree(response.pointer);
757 }
758 
759 static int huawei_wmi_input_setup(struct device *dev,
760 		const char *guid,
761 		struct input_dev **idev)
762 {
763 	*idev = devm_input_allocate_device(dev);
764 	if (!*idev)
765 		return -ENOMEM;
766 
767 	(*idev)->name = "Huawei WMI hotkeys";
768 	(*idev)->phys = "wmi/input0";
769 	(*idev)->id.bustype = BUS_HOST;
770 	(*idev)->dev.parent = dev;
771 
772 	return sparse_keymap_setup(*idev, huawei_wmi_keymap, NULL) ||
773 		input_register_device(*idev) ||
774 		wmi_install_notify_handler(guid, huawei_wmi_input_notify,
775 				*idev);
776 }
777 
778 static void huawei_wmi_input_exit(struct device *dev, const char *guid)
779 {
780 	wmi_remove_notify_handler(guid);
781 }
782 
783 /* Huawei driver */
784 
785 static const struct wmi_device_id huawei_wmi_events_id_table[] = {
786 	{ .guid_string = WMI0_EVENT_GUID },
787 	{ .guid_string = HWMI_EVENT_GUID },
788 	{  }
789 };
790 
791 static int huawei_wmi_probe(struct platform_device *pdev)
792 {
793 	const struct wmi_device_id *guid = huawei_wmi_events_id_table;
794 	int err;
795 
796 	platform_set_drvdata(pdev, huawei_wmi);
797 	huawei_wmi->dev = &pdev->dev;
798 
799 	while (*guid->guid_string) {
800 		struct input_dev *idev = *huawei_wmi->idev;
801 
802 		if (wmi_has_guid(guid->guid_string)) {
803 			err = huawei_wmi_input_setup(&pdev->dev, guid->guid_string, &idev);
804 			if (err) {
805 				dev_err(&pdev->dev, "Failed to setup input on %s\n", guid->guid_string);
806 				return err;
807 			}
808 		}
809 
810 		idev++;
811 		guid++;
812 	}
813 
814 	if (wmi_has_guid(HWMI_METHOD_GUID)) {
815 		mutex_init(&huawei_wmi->wmi_lock);
816 
817 		huawei_wmi_leds_setup(&pdev->dev);
818 		huawei_wmi_fn_lock_setup(&pdev->dev);
819 		huawei_wmi_battery_setup(&pdev->dev);
820 		huawei_wmi_debugfs_setup(&pdev->dev);
821 	}
822 
823 	return 0;
824 }
825 
826 static int huawei_wmi_remove(struct platform_device *pdev)
827 {
828 	const struct wmi_device_id *guid = huawei_wmi_events_id_table;
829 
830 	while (*guid->guid_string) {
831 		if (wmi_has_guid(guid->guid_string))
832 			huawei_wmi_input_exit(&pdev->dev, guid->guid_string);
833 
834 		guid++;
835 	}
836 
837 	if (wmi_has_guid(HWMI_METHOD_GUID)) {
838 		huawei_wmi_debugfs_exit(&pdev->dev);
839 		huawei_wmi_battery_exit(&pdev->dev);
840 		huawei_wmi_fn_lock_exit(&pdev->dev);
841 	}
842 
843 	return 0;
844 }
845 
846 static struct platform_driver huawei_wmi_driver = {
847 	.driver = {
848 		.name = "huawei-wmi",
849 	},
850 	.probe = huawei_wmi_probe,
851 	.remove = huawei_wmi_remove,
852 };
853 
854 static __init int huawei_wmi_init(void)
855 {
856 	struct platform_device *pdev;
857 	int err;
858 
859 	huawei_wmi = kzalloc(sizeof(struct huawei_wmi), GFP_KERNEL);
860 	if (!huawei_wmi)
861 		return -ENOMEM;
862 
863 	quirks = &quirk_unknown;
864 	dmi_check_system(huawei_quirks);
865 	if (battery_reset != -1)
866 		quirks->battery_reset = battery_reset;
867 	if (report_brightness != -1)
868 		quirks->report_brightness = report_brightness;
869 
870 	err = platform_driver_register(&huawei_wmi_driver);
871 	if (err)
872 		goto pdrv_err;
873 
874 	pdev = platform_device_register_simple("huawei-wmi", -1, NULL, 0);
875 	if (IS_ERR(pdev)) {
876 		err = PTR_ERR(pdev);
877 		goto pdev_err;
878 	}
879 
880 	return 0;
881 
882 pdev_err:
883 	platform_driver_unregister(&huawei_wmi_driver);
884 pdrv_err:
885 	kfree(huawei_wmi);
886 	return err;
887 }
888 
889 static __exit void huawei_wmi_exit(void)
890 {
891 	struct platform_device *pdev = to_platform_device(huawei_wmi->dev);
892 
893 	platform_device_unregister(pdev);
894 	platform_driver_unregister(&huawei_wmi_driver);
895 
896 	kfree(huawei_wmi);
897 }
898 
899 module_init(huawei_wmi_init);
900 module_exit(huawei_wmi_exit);
901 
902 MODULE_ALIAS("wmi:"HWMI_METHOD_GUID);
903 MODULE_DEVICE_TABLE(wmi, huawei_wmi_events_id_table);
904 MODULE_AUTHOR("Ayman Bagabas <ayman.bagabas@gmail.com>");
905 MODULE_DESCRIPTION("Huawei WMI laptop extras driver");
906 MODULE_LICENSE("GPL v2");
907