xref: /openbmc/linux/drivers/platform/x86/msi-wmi.c (revision a09d2831)
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 
24 #include <linux/kernel.h>
25 #include <linux/input.h>
26 #include <linux/input/sparse-keymap.h>
27 #include <linux/acpi.h>
28 #include <linux/backlight.h>
29 
30 MODULE_AUTHOR("Thomas Renninger <trenn@suse.de>");
31 MODULE_DESCRIPTION("MSI laptop WMI hotkeys driver");
32 MODULE_LICENSE("GPL");
33 
34 MODULE_ALIAS("wmi:551A1F84-FBDD-4125-91DB-3EA8F44F1D45");
35 MODULE_ALIAS("wmi:B6F3EEF2-3D2F-49DC-9DE3-85BCE18C62F2");
36 
37 #define DRV_NAME "msi-wmi"
38 #define DRV_PFX DRV_NAME ": "
39 
40 #define MSIWMI_BIOS_GUID "551A1F84-FBDD-4125-91DB-3EA8F44F1D45"
41 #define MSIWMI_EVENT_GUID "B6F3EEF2-3D2F-49DC-9DE3-85BCE18C62F2"
42 
43 #define dprintk(msg...) pr_debug(DRV_PFX msg)
44 
45 #define KEYCODE_BASE 0xD0
46 #define MSI_WMI_BRIGHTNESSUP   KEYCODE_BASE
47 #define MSI_WMI_BRIGHTNESSDOWN (KEYCODE_BASE + 1)
48 #define MSI_WMI_VOLUMEUP       (KEYCODE_BASE + 2)
49 #define MSI_WMI_VOLUMEDOWN     (KEYCODE_BASE + 3)
50 static struct key_entry msi_wmi_keymap[] = {
51 	{ KE_KEY, MSI_WMI_BRIGHTNESSUP,   {KEY_BRIGHTNESSUP} },
52 	{ KE_KEY, MSI_WMI_BRIGHTNESSDOWN, {KEY_BRIGHTNESSDOWN} },
53 	{ KE_KEY, MSI_WMI_VOLUMEUP,       {KEY_VOLUMEUP} },
54 	{ KE_KEY, MSI_WMI_VOLUMEDOWN,     {KEY_VOLUMEDOWN} },
55 	{ KE_END, 0}
56 };
57 static ktime_t last_pressed[ARRAY_SIZE(msi_wmi_keymap) - 1];
58 
59 struct backlight_device *backlight;
60 
61 static int backlight_map[] = { 0x00, 0x33, 0x66, 0x99, 0xCC, 0xFF };
62 
63 static struct input_dev *msi_wmi_input_dev;
64 
65 static int msi_wmi_query_block(int instance, int *ret)
66 {
67 	acpi_status status;
68 	union acpi_object *obj;
69 
70 	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
71 
72 	status = wmi_query_block(MSIWMI_BIOS_GUID, instance, &output);
73 
74 	obj = output.pointer;
75 
76 	if (!obj || obj->type != ACPI_TYPE_INTEGER) {
77 		if (obj) {
78 			printk(KERN_ERR DRV_PFX "query block returned object "
79 			       "type: %d - buffer length:%d\n", obj->type,
80 			       obj->type == ACPI_TYPE_BUFFER ?
81 			       obj->buffer.length : 0);
82 		}
83 		kfree(obj);
84 		return -EINVAL;
85 	}
86 	*ret = obj->integer.value;
87 	kfree(obj);
88 	return 0;
89 }
90 
91 static int msi_wmi_set_block(int instance, int value)
92 {
93 	acpi_status status;
94 
95 	struct acpi_buffer input = { sizeof(int), &value };
96 
97 	dprintk("Going to set block of instance: %d - value: %d\n",
98 		instance, value);
99 
100 	status = wmi_set_block(MSIWMI_BIOS_GUID, instance, &input);
101 
102 	return ACPI_SUCCESS(status) ? 0 : 1;
103 }
104 
105 static int bl_get(struct backlight_device *bd)
106 {
107 	int level, err, ret;
108 
109 	/* Instance 1 is "get backlight", cmp with DSDT */
110 	err = msi_wmi_query_block(1, &ret);
111 	if (err) {
112 		printk(KERN_ERR DRV_PFX "Could not query backlight: %d\n", err);
113 		return -EINVAL;
114 	}
115 	dprintk("Get: Query block returned: %d\n", ret);
116 	for (level = 0; level < ARRAY_SIZE(backlight_map); level++) {
117 		if (backlight_map[level] == ret) {
118 			dprintk("Current backlight level: 0x%X - index: %d\n",
119 				backlight_map[level], level);
120 			break;
121 		}
122 	}
123 	if (level == ARRAY_SIZE(backlight_map)) {
124 		printk(KERN_ERR DRV_PFX "get: Invalid brightness value: 0x%X\n",
125 		       ret);
126 		return -EINVAL;
127 	}
128 	return level;
129 }
130 
131 static int bl_set_status(struct backlight_device *bd)
132 {
133 	int bright = bd->props.brightness;
134 	if (bright >= ARRAY_SIZE(backlight_map) || bright < 0)
135 		return -EINVAL;
136 
137 	/* Instance 0 is "set backlight" */
138 	return msi_wmi_set_block(0, backlight_map[bright]);
139 }
140 
141 static struct backlight_ops msi_backlight_ops = {
142 	.get_brightness	= bl_get,
143 	.update_status	= bl_set_status,
144 };
145 
146 static void msi_wmi_notify(u32 value, void *context)
147 {
148 	struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
149 	static struct key_entry *key;
150 	union acpi_object *obj;
151 	ktime_t cur;
152 	acpi_status status;
153 
154 	status = wmi_get_event_data(value, &response);
155 	if (status != AE_OK) {
156 		printk(KERN_INFO DRV_PFX "bad event status 0x%x\n", status);
157 		return;
158 	}
159 
160 	obj = (union acpi_object *)response.pointer;
161 
162 	if (obj && obj->type == ACPI_TYPE_INTEGER) {
163 		int eventcode = obj->integer.value;
164 		dprintk("Eventcode: 0x%x\n", eventcode);
165 		key = sparse_keymap_entry_from_scancode(msi_wmi_input_dev,
166 				eventcode);
167 		if (key) {
168 			ktime_t diff;
169 			cur = ktime_get_real();
170 			diff = ktime_sub(cur, last_pressed[key->code -
171 					KEYCODE_BASE]);
172 			/* Ignore event if the same event happened in a 50 ms
173 			   timeframe -> Key press may result in 10-20 GPEs */
174 			if (ktime_to_us(diff) < 1000 * 50) {
175 				dprintk("Suppressed key event 0x%X - "
176 					"Last press was %lld us ago\n",
177 					 key->code, ktime_to_us(diff));
178 				return;
179 			}
180 			last_pressed[key->code - KEYCODE_BASE] = cur;
181 
182 			if (key->type == KE_KEY &&
183 			/* Brightness is served via acpi video driver */
184 			(!acpi_video_backlight_support() ||
185 			(key->code != MSI_WMI_BRIGHTNESSUP &&
186 			key->code != MSI_WMI_BRIGHTNESSDOWN))) {
187 				dprintk("Send key: 0x%X - "
188 					"Input layer keycode: %d\n", key->code,
189 					 key->keycode);
190 				sparse_keymap_report_entry(msi_wmi_input_dev,
191 						key, 1, true);
192 			}
193 		} else
194 			printk(KERN_INFO "Unknown key pressed - %x\n",
195 			       eventcode);
196 	} else
197 		printk(KERN_INFO DRV_PFX "Unknown event received\n");
198 	kfree(response.pointer);
199 }
200 
201 static int __init msi_wmi_input_setup(void)
202 {
203 	int err;
204 
205 	msi_wmi_input_dev = input_allocate_device();
206 	if (!msi_wmi_input_dev)
207 		return -ENOMEM;
208 
209 	msi_wmi_input_dev->name = "MSI WMI hotkeys";
210 	msi_wmi_input_dev->phys = "wmi/input0";
211 	msi_wmi_input_dev->id.bustype = BUS_HOST;
212 
213 	err = sparse_keymap_setup(msi_wmi_input_dev, msi_wmi_keymap, NULL);
214 	if (err)
215 		goto err_free_dev;
216 
217 	err = input_register_device(msi_wmi_input_dev);
218 
219 	if (err)
220 		goto err_free_keymap;
221 
222 	memset(last_pressed, 0, sizeof(last_pressed));
223 
224 	return 0;
225 
226 err_free_keymap:
227 	sparse_keymap_free(msi_wmi_input_dev);
228 err_free_dev:
229 	input_free_device(msi_wmi_input_dev);
230 	return err;
231 }
232 
233 static int __init msi_wmi_init(void)
234 {
235 	int err;
236 
237 	if (!wmi_has_guid(MSIWMI_EVENT_GUID)) {
238 		printk(KERN_ERR
239 		       "This machine doesn't have MSI-hotkeys through WMI\n");
240 		return -ENODEV;
241 	}
242 	err = wmi_install_notify_handler(MSIWMI_EVENT_GUID,
243 			msi_wmi_notify, NULL);
244 	if (ACPI_FAILURE(err))
245 		return -EINVAL;
246 
247 	err = msi_wmi_input_setup();
248 	if (err)
249 		goto err_uninstall_notifier;
250 
251 	if (!acpi_video_backlight_support()) {
252 		backlight = backlight_device_register(DRV_NAME,
253 				NULL, NULL, &msi_backlight_ops);
254 		if (IS_ERR(backlight))
255 			goto err_free_input;
256 
257 		backlight->props.max_brightness = ARRAY_SIZE(backlight_map) - 1;
258 		err = bl_get(NULL);
259 		if (err < 0)
260 			goto err_free_backlight;
261 
262 		backlight->props.brightness = err;
263 	}
264 	dprintk("Event handler installed\n");
265 
266 	return 0;
267 
268 err_free_backlight:
269 	backlight_device_unregister(backlight);
270 err_free_input:
271 	input_unregister_device(msi_wmi_input_dev);
272 err_uninstall_notifier:
273 	wmi_remove_notify_handler(MSIWMI_EVENT_GUID);
274 	return err;
275 }
276 
277 static void __exit msi_wmi_exit(void)
278 {
279 	if (wmi_has_guid(MSIWMI_EVENT_GUID)) {
280 		wmi_remove_notify_handler(MSIWMI_EVENT_GUID);
281 		sparse_keymap_free(msi_wmi_input_dev);
282 		input_unregister_device(msi_wmi_input_dev);
283 		backlight_device_unregister(backlight);
284 	}
285 }
286 
287 module_init(msi_wmi_init);
288 module_exit(msi_wmi_exit);
289