xref: /openbmc/linux/drivers/platform/x86/msi-wmi.c (revision 565d76cb)
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 #include <linux/slab.h>
30 
31 MODULE_AUTHOR("Thomas Renninger <trenn@suse.de>");
32 MODULE_DESCRIPTION("MSI laptop WMI hotkeys driver");
33 MODULE_LICENSE("GPL");
34 
35 MODULE_ALIAS("wmi:551A1F84-FBDD-4125-91DB-3EA8F44F1D45");
36 MODULE_ALIAS("wmi:B6F3EEF2-3D2F-49DC-9DE3-85BCE18C62F2");
37 
38 #define DRV_NAME "msi-wmi"
39 #define DRV_PFX DRV_NAME ": "
40 
41 #define MSIWMI_BIOS_GUID "551A1F84-FBDD-4125-91DB-3EA8F44F1D45"
42 #define MSIWMI_EVENT_GUID "B6F3EEF2-3D2F-49DC-9DE3-85BCE18C62F2"
43 
44 #define dprintk(msg...) pr_debug(DRV_PFX msg)
45 
46 #define SCANCODE_BASE 0xD0
47 #define MSI_WMI_BRIGHTNESSUP   SCANCODE_BASE
48 #define MSI_WMI_BRIGHTNESSDOWN (SCANCODE_BASE + 1)
49 #define MSI_WMI_VOLUMEUP       (SCANCODE_BASE + 2)
50 #define MSI_WMI_VOLUMEDOWN     (SCANCODE_BASE + 3)
51 #define MSI_WMI_MUTE           (SCANCODE_BASE + 4)
52 static struct key_entry msi_wmi_keymap[] = {
53 	{ KE_KEY, MSI_WMI_BRIGHTNESSUP,   {KEY_BRIGHTNESSUP} },
54 	{ KE_KEY, MSI_WMI_BRIGHTNESSDOWN, {KEY_BRIGHTNESSDOWN} },
55 	{ KE_KEY, MSI_WMI_VOLUMEUP,       {KEY_VOLUMEUP} },
56 	{ KE_KEY, MSI_WMI_VOLUMEDOWN,     {KEY_VOLUMEDOWN} },
57 	{ KE_KEY, MSI_WMI_MUTE,           {KEY_MUTE} },
58 	{ KE_END, 0}
59 };
60 static ktime_t last_pressed[ARRAY_SIZE(msi_wmi_keymap) - 1];
61 
62 static struct backlight_device *backlight;
63 
64 static int backlight_map[] = { 0x00, 0x33, 0x66, 0x99, 0xCC, 0xFF };
65 
66 static struct input_dev *msi_wmi_input_dev;
67 
68 static int msi_wmi_query_block(int instance, int *ret)
69 {
70 	acpi_status status;
71 	union acpi_object *obj;
72 
73 	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
74 
75 	status = wmi_query_block(MSIWMI_BIOS_GUID, instance, &output);
76 
77 	obj = output.pointer;
78 
79 	if (!obj || obj->type != ACPI_TYPE_INTEGER) {
80 		if (obj) {
81 			printk(KERN_ERR DRV_PFX "query block returned object "
82 			       "type: %d - buffer length:%d\n", obj->type,
83 			       obj->type == ACPI_TYPE_BUFFER ?
84 			       obj->buffer.length : 0);
85 		}
86 		kfree(obj);
87 		return -EINVAL;
88 	}
89 	*ret = obj->integer.value;
90 	kfree(obj);
91 	return 0;
92 }
93 
94 static int msi_wmi_set_block(int instance, int value)
95 {
96 	acpi_status status;
97 
98 	struct acpi_buffer input = { sizeof(int), &value };
99 
100 	dprintk("Going to set block of instance: %d - value: %d\n",
101 		instance, value);
102 
103 	status = wmi_set_block(MSIWMI_BIOS_GUID, instance, &input);
104 
105 	return ACPI_SUCCESS(status) ? 0 : 1;
106 }
107 
108 static int bl_get(struct backlight_device *bd)
109 {
110 	int level, err, ret;
111 
112 	/* Instance 1 is "get backlight", cmp with DSDT */
113 	err = msi_wmi_query_block(1, &ret);
114 	if (err) {
115 		printk(KERN_ERR DRV_PFX "Could not query backlight: %d\n", err);
116 		return -EINVAL;
117 	}
118 	dprintk("Get: Query block returned: %d\n", ret);
119 	for (level = 0; level < ARRAY_SIZE(backlight_map); level++) {
120 		if (backlight_map[level] == ret) {
121 			dprintk("Current backlight level: 0x%X - index: %d\n",
122 				backlight_map[level], level);
123 			break;
124 		}
125 	}
126 	if (level == ARRAY_SIZE(backlight_map)) {
127 		printk(KERN_ERR DRV_PFX "get: Invalid brightness value: 0x%X\n",
128 		       ret);
129 		return -EINVAL;
130 	}
131 	return level;
132 }
133 
134 static int bl_set_status(struct backlight_device *bd)
135 {
136 	int bright = bd->props.brightness;
137 	if (bright >= ARRAY_SIZE(backlight_map) || bright < 0)
138 		return -EINVAL;
139 
140 	/* Instance 0 is "set backlight" */
141 	return msi_wmi_set_block(0, backlight_map[bright]);
142 }
143 
144 static const struct backlight_ops msi_backlight_ops = {
145 	.get_brightness	= bl_get,
146 	.update_status	= bl_set_status,
147 };
148 
149 static void msi_wmi_notify(u32 value, void *context)
150 {
151 	struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
152 	static struct key_entry *key;
153 	union acpi_object *obj;
154 	ktime_t cur;
155 	acpi_status status;
156 
157 	status = wmi_get_event_data(value, &response);
158 	if (status != AE_OK) {
159 		printk(KERN_INFO DRV_PFX "bad event status 0x%x\n", status);
160 		return;
161 	}
162 
163 	obj = (union acpi_object *)response.pointer;
164 
165 	if (obj && obj->type == ACPI_TYPE_INTEGER) {
166 		int eventcode = obj->integer.value;
167 		dprintk("Eventcode: 0x%x\n", eventcode);
168 		key = sparse_keymap_entry_from_scancode(msi_wmi_input_dev,
169 				eventcode);
170 		if (key) {
171 			ktime_t diff;
172 			cur = ktime_get_real();
173 			diff = ktime_sub(cur, last_pressed[key->code -
174 					SCANCODE_BASE]);
175 			/* Ignore event if the same event happened in a 50 ms
176 			   timeframe -> Key press may result in 10-20 GPEs */
177 			if (ktime_to_us(diff) < 1000 * 50) {
178 				dprintk("Suppressed key event 0x%X - "
179 					"Last press was %lld us ago\n",
180 					 key->code, ktime_to_us(diff));
181 				return;
182 			}
183 			last_pressed[key->code - SCANCODE_BASE] = cur;
184 
185 			if (key->type == KE_KEY &&
186 			/* Brightness is served via acpi video driver */
187 			(!acpi_video_backlight_support() ||
188 			(key->code != MSI_WMI_BRIGHTNESSUP &&
189 			key->code != MSI_WMI_BRIGHTNESSDOWN))) {
190 				dprintk("Send key: 0x%X - "
191 					"Input layer keycode: %d\n", key->code,
192 					 key->keycode);
193 				sparse_keymap_report_entry(msi_wmi_input_dev,
194 						key, 1, true);
195 			}
196 		} else
197 			printk(KERN_INFO "Unknown key pressed - %x\n",
198 			       eventcode);
199 	} else
200 		printk(KERN_INFO DRV_PFX "Unknown event received\n");
201 	kfree(response.pointer);
202 }
203 
204 static int __init msi_wmi_input_setup(void)
205 {
206 	int err;
207 
208 	msi_wmi_input_dev = input_allocate_device();
209 	if (!msi_wmi_input_dev)
210 		return -ENOMEM;
211 
212 	msi_wmi_input_dev->name = "MSI WMI hotkeys";
213 	msi_wmi_input_dev->phys = "wmi/input0";
214 	msi_wmi_input_dev->id.bustype = BUS_HOST;
215 
216 	err = sparse_keymap_setup(msi_wmi_input_dev, msi_wmi_keymap, NULL);
217 	if (err)
218 		goto err_free_dev;
219 
220 	err = input_register_device(msi_wmi_input_dev);
221 
222 	if (err)
223 		goto err_free_keymap;
224 
225 	memset(last_pressed, 0, sizeof(last_pressed));
226 
227 	return 0;
228 
229 err_free_keymap:
230 	sparse_keymap_free(msi_wmi_input_dev);
231 err_free_dev:
232 	input_free_device(msi_wmi_input_dev);
233 	return err;
234 }
235 
236 static int __init msi_wmi_init(void)
237 {
238 	int err;
239 
240 	if (!wmi_has_guid(MSIWMI_EVENT_GUID)) {
241 		printk(KERN_ERR
242 		       "This machine doesn't have MSI-hotkeys through WMI\n");
243 		return -ENODEV;
244 	}
245 	err = wmi_install_notify_handler(MSIWMI_EVENT_GUID,
246 			msi_wmi_notify, NULL);
247 	if (ACPI_FAILURE(err))
248 		return -EINVAL;
249 
250 	err = msi_wmi_input_setup();
251 	if (err)
252 		goto err_uninstall_notifier;
253 
254 	if (!acpi_video_backlight_support()) {
255 		struct backlight_properties props;
256 		memset(&props, 0, sizeof(struct backlight_properties));
257 		props.type = BACKLIGHT_PLATFORM;
258 		props.max_brightness = ARRAY_SIZE(backlight_map) - 1;
259 		backlight = backlight_device_register(DRV_NAME, NULL, NULL,
260 						      &msi_backlight_ops,
261 						      &props);
262 		if (IS_ERR(backlight)) {
263 			err = PTR_ERR(backlight);
264 			goto err_free_input;
265 		}
266 
267 		err = bl_get(NULL);
268 		if (err < 0)
269 			goto err_free_backlight;
270 
271 		backlight->props.brightness = err;
272 	}
273 	dprintk("Event handler installed\n");
274 
275 	return 0;
276 
277 err_free_backlight:
278 	backlight_device_unregister(backlight);
279 err_free_input:
280 	input_unregister_device(msi_wmi_input_dev);
281 err_uninstall_notifier:
282 	wmi_remove_notify_handler(MSIWMI_EVENT_GUID);
283 	return err;
284 }
285 
286 static void __exit msi_wmi_exit(void)
287 {
288 	if (wmi_has_guid(MSIWMI_EVENT_GUID)) {
289 		wmi_remove_notify_handler(MSIWMI_EVENT_GUID);
290 		sparse_keymap_free(msi_wmi_input_dev);
291 		input_unregister_device(msi_wmi_input_dev);
292 		backlight_device_unregister(backlight);
293 	}
294 }
295 
296 module_init(msi_wmi_init);
297 module_exit(msi_wmi_exit);
298