1 /*
2  * MSI WMI hotkeys
3  *
4  * Copyright (C) 2009 Novell <trenn@suse.de>
5  *
6  * Most stuff taken over from hp-wmi
7  *
8  *  This program is free software; you can redistribute it and/or modify
9  *  it under the terms of the GNU General Public License as published by
10  *  the Free Software Foundation; either version 2 of the License, or
11  *  (at your option) any later version.
12  *
13  *  This program is distributed in the hope that it will be useful,
14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  *  GNU General Public License for more details.
17  *
18  *  You should have received a copy of the GNU General Public License
19  *  along with this program; if not, write to the Free Software
20  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
21  */
22 
23 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
24 
25 #include <linux/kernel.h>
26 #include <linux/input.h>
27 #include <linux/input/sparse-keymap.h>
28 #include <linux/acpi.h>
29 #include <linux/backlight.h>
30 #include <linux/slab.h>
31 #include <linux/module.h>
32 
33 MODULE_AUTHOR("Thomas Renninger <trenn@suse.de>");
34 MODULE_DESCRIPTION("MSI laptop WMI hotkeys driver");
35 MODULE_LICENSE("GPL");
36 
37 MODULE_ALIAS("wmi:551A1F84-FBDD-4125-91DB-3EA8F44F1D45");
38 MODULE_ALIAS("wmi:B6F3EEF2-3D2F-49DC-9DE3-85BCE18C62F2");
39 
40 #define DRV_NAME "msi-wmi"
41 
42 #define MSIWMI_BIOS_GUID "551A1F84-FBDD-4125-91DB-3EA8F44F1D45"
43 #define MSIWMI_EVENT_GUID "B6F3EEF2-3D2F-49DC-9DE3-85BCE18C62F2"
44 
45 #define SCANCODE_BASE 0xD0
46 #define MSI_WMI_BRIGHTNESSUP   SCANCODE_BASE
47 #define MSI_WMI_BRIGHTNESSDOWN (SCANCODE_BASE + 1)
48 #define MSI_WMI_VOLUMEUP       (SCANCODE_BASE + 2)
49 #define MSI_WMI_VOLUMEDOWN     (SCANCODE_BASE + 3)
50 #define MSI_WMI_MUTE           (SCANCODE_BASE + 4)
51 static struct key_entry msi_wmi_keymap[] = {
52 	{ KE_KEY, MSI_WMI_BRIGHTNESSUP,   {KEY_BRIGHTNESSUP} },
53 	{ KE_KEY, MSI_WMI_BRIGHTNESSDOWN, {KEY_BRIGHTNESSDOWN} },
54 	{ KE_KEY, MSI_WMI_VOLUMEUP,       {KEY_VOLUMEUP} },
55 	{ KE_KEY, MSI_WMI_VOLUMEDOWN,     {KEY_VOLUMEDOWN} },
56 	{ KE_KEY, MSI_WMI_MUTE,           {KEY_MUTE} },
57 	{ KE_END, 0}
58 };
59 static ktime_t last_pressed[ARRAY_SIZE(msi_wmi_keymap) - 1];
60 
61 static struct backlight_device *backlight;
62 
63 static int backlight_map[] = { 0x00, 0x33, 0x66, 0x99, 0xCC, 0xFF };
64 
65 static struct input_dev *msi_wmi_input_dev;
66 
msi_wmi_query_block(int instance,int * ret)67 static int msi_wmi_query_block(int instance, int *ret)
68 {
69 	acpi_status status;
70 	union acpi_object *obj;
71 
72 	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
73 
74 	status = wmi_query_block(MSIWMI_BIOS_GUID, instance, &output);
75 
76 	obj = output.pointer;
77 
78 	if (!obj || obj->type != ACPI_TYPE_INTEGER) {
79 		if (obj) {
80 			pr_err("query block returned object "
81 			       "type: %d - buffer length:%d\n", obj->type,
82 			       obj->type == ACPI_TYPE_BUFFER ?
83 			       obj->buffer.length : 0);
84 		}
85 		kfree(obj);
86 		return -EINVAL;
87 	}
88 	*ret = obj->integer.value;
89 	kfree(obj);
90 	return 0;
91 }
92 
msi_wmi_set_block(int instance,int value)93 static int msi_wmi_set_block(int instance, int value)
94 {
95 	acpi_status status;
96 
97 	struct acpi_buffer input = { sizeof(int), &value };
98 
99 	pr_debug("Going to set block of instance: %d - value: %d\n",
100 		 instance, value);
101 
102 	status = wmi_set_block(MSIWMI_BIOS_GUID, instance, &input);
103 
104 	return ACPI_SUCCESS(status) ? 0 : 1;
105 }
106 
bl_get(struct backlight_device * bd)107 static int bl_get(struct backlight_device *bd)
108 {
109 	int level, err, ret;
110 
111 	/* Instance 1 is "get backlight", cmp with DSDT */
112 	err = msi_wmi_query_block(1, &ret);
113 	if (err) {
114 		pr_err("Could not query backlight: %d\n", err);
115 		return -EINVAL;
116 	}
117 	pr_debug("Get: Query block returned: %d\n", ret);
118 	for (level = 0; level < ARRAY_SIZE(backlight_map); level++) {
119 		if (backlight_map[level] == ret) {
120 			pr_debug("Current backlight level: 0x%X - index: %d\n",
121 				 backlight_map[level], level);
122 			break;
123 		}
124 	}
125 	if (level == ARRAY_SIZE(backlight_map)) {
126 		pr_err("get: Invalid brightness value: 0x%X\n", ret);
127 		return -EINVAL;
128 	}
129 	return level;
130 }
131 
bl_set_status(struct backlight_device * bd)132 static int bl_set_status(struct backlight_device *bd)
133 {
134 	int bright = bd->props.brightness;
135 	if (bright >= ARRAY_SIZE(backlight_map) || bright < 0)
136 		return -EINVAL;
137 
138 	/* Instance 0 is "set backlight" */
139 	return msi_wmi_set_block(0, backlight_map[bright]);
140 }
141 
142 static const struct backlight_ops msi_backlight_ops = {
143 	.get_brightness	= bl_get,
144 	.update_status	= bl_set_status,
145 };
146 
msi_wmi_notify(u32 value,void * context)147 static void msi_wmi_notify(u32 value, void *context)
148 {
149 	struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
150 	static struct key_entry *key;
151 	union acpi_object *obj;
152 	ktime_t cur;
153 	acpi_status status;
154 
155 	status = wmi_get_event_data(value, &response);
156 	if (status != AE_OK) {
157 		pr_info("bad event status 0x%x\n", status);
158 		return;
159 	}
160 
161 	obj = (union acpi_object *)response.pointer;
162 
163 	if (obj && obj->type == ACPI_TYPE_INTEGER) {
164 		int eventcode = obj->integer.value;
165 		pr_debug("Eventcode: 0x%x\n", eventcode);
166 		key = sparse_keymap_entry_from_scancode(msi_wmi_input_dev,
167 				eventcode);
168 		if (key) {
169 			ktime_t diff;
170 			cur = ktime_get_real();
171 			diff = ktime_sub(cur, last_pressed[key->code -
172 					SCANCODE_BASE]);
173 			/* Ignore event if the same event happened in a 50 ms
174 			   timeframe -> Key press may result in 10-20 GPEs */
175 			if (ktime_to_us(diff) < 1000 * 50) {
176 				pr_debug("Suppressed key event 0x%X - "
177 					 "Last press was %lld us ago\n",
178 					 key->code, ktime_to_us(diff));
179 				goto msi_wmi_notify_exit;
180 			}
181 			last_pressed[key->code - SCANCODE_BASE] = cur;
182 
183 			if (key->type == KE_KEY &&
184 			/* Brightness is served via acpi video driver */
185 			(!acpi_video_backlight_support() ||
186 			(key->code != MSI_WMI_BRIGHTNESSUP &&
187 			key->code != MSI_WMI_BRIGHTNESSDOWN))) {
188 				pr_debug("Send key: 0x%X - "
189 					 "Input layer keycode: %d\n",
190 					 key->code, key->keycode);
191 				sparse_keymap_report_entry(msi_wmi_input_dev,
192 						key, 1, true);
193 			}
194 		} else
195 			pr_info("Unknown key pressed - %x\n", eventcode);
196 	} else
197 		pr_info("Unknown event received\n");
198 
199 msi_wmi_notify_exit:
200 	kfree(response.pointer);
201 }
202 
msi_wmi_input_setup(void)203 static int __init msi_wmi_input_setup(void)
204 {
205 	int err;
206 
207 	msi_wmi_input_dev = input_allocate_device();
208 	if (!msi_wmi_input_dev)
209 		return -ENOMEM;
210 
211 	msi_wmi_input_dev->name = "MSI WMI hotkeys";
212 	msi_wmi_input_dev->phys = "wmi/input0";
213 	msi_wmi_input_dev->id.bustype = BUS_HOST;
214 
215 	err = sparse_keymap_setup(msi_wmi_input_dev, msi_wmi_keymap, NULL);
216 	if (err)
217 		goto err_free_dev;
218 
219 	err = input_register_device(msi_wmi_input_dev);
220 
221 	if (err)
222 		goto err_free_keymap;
223 
224 	memset(last_pressed, 0, sizeof(last_pressed));
225 
226 	return 0;
227 
228 err_free_keymap:
229 	sparse_keymap_free(msi_wmi_input_dev);
230 err_free_dev:
231 	input_free_device(msi_wmi_input_dev);
232 	return err;
233 }
234 
msi_wmi_init(void)235 static int __init msi_wmi_init(void)
236 {
237 	int err;
238 
239 	if (!wmi_has_guid(MSIWMI_EVENT_GUID)) {
240 		pr_err("This machine doesn't have MSI-hotkeys through WMI\n");
241 		return -ENODEV;
242 	}
243 	err = wmi_install_notify_handler(MSIWMI_EVENT_GUID,
244 			msi_wmi_notify, NULL);
245 	if (ACPI_FAILURE(err))
246 		return -EINVAL;
247 
248 	err = msi_wmi_input_setup();
249 	if (err)
250 		goto err_uninstall_notifier;
251 
252 	if (!acpi_video_backlight_support()) {
253 		struct backlight_properties props;
254 		memset(&props, 0, sizeof(struct backlight_properties));
255 		props.type = BACKLIGHT_PLATFORM;
256 		props.max_brightness = ARRAY_SIZE(backlight_map) - 1;
257 		backlight = backlight_device_register(DRV_NAME, NULL, NULL,
258 						      &msi_backlight_ops,
259 						      &props);
260 		if (IS_ERR(backlight)) {
261 			err = PTR_ERR(backlight);
262 			goto err_free_input;
263 		}
264 
265 		err = bl_get(NULL);
266 		if (err < 0)
267 			goto err_free_backlight;
268 
269 		backlight->props.brightness = err;
270 	}
271 	pr_debug("Event handler installed\n");
272 
273 	return 0;
274 
275 err_free_backlight:
276 	backlight_device_unregister(backlight);
277 err_free_input:
278 	sparse_keymap_free(msi_wmi_input_dev);
279 	input_unregister_device(msi_wmi_input_dev);
280 err_uninstall_notifier:
281 	wmi_remove_notify_handler(MSIWMI_EVENT_GUID);
282 	return err;
283 }
284 
msi_wmi_exit(void)285 static void __exit msi_wmi_exit(void)
286 {
287 	if (wmi_has_guid(MSIWMI_EVENT_GUID)) {
288 		wmi_remove_notify_handler(MSIWMI_EVENT_GUID);
289 		sparse_keymap_free(msi_wmi_input_dev);
290 		input_unregister_device(msi_wmi_input_dev);
291 		backlight_device_unregister(backlight);
292 	}
293 }
294 
295 module_init(msi_wmi_init);
296 module_exit(msi_wmi_exit);
297