/drivers/platform/x86/msi-wmi.c

  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
 32MODULE_AUTHOR("Thomas Renninger <trenn@suse.de>");
 33MODULE_DESCRIPTION("MSI laptop WMI hotkeys driver");
 34MODULE_LICENSE("GPL");
 35
 36MODULE_ALIAS("wmi:551A1F84-FBDD-4125-91DB-3EA8F44F1D45");
 37MODULE_ALIAS("wmi:B6F3EEF2-3D2F-49DC-9DE3-85BCE18C62F2");
 38
 39#define DRV_NAME "msi-wmi"
 40
 41#define MSIWMI_BIOS_GUID "551A1F84-FBDD-4125-91DB-3EA8F44F1D45"
 42#define MSIWMI_EVENT_GUID "B6F3EEF2-3D2F-49DC-9DE3-85BCE18C62F2"
 43
 44#define SCANCODE_BASE 0xD0
 45#define MSI_WMI_BRIGHTNESSUP   SCANCODE_BASE
 46#define MSI_WMI_BRIGHTNESSDOWN (SCANCODE_BASE + 1)
 47#define MSI_WMI_VOLUMEUP       (SCANCODE_BASE + 2)
 48#define MSI_WMI_VOLUMEDOWN     (SCANCODE_BASE + 3)
 49#define MSI_WMI_MUTE           (SCANCODE_BASE + 4)
 50static 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_KEY, MSI_WMI_MUTE,           {KEY_MUTE} },
 56	{ KE_END, 0}
 57};
 58static ktime_t last_pressed[ARRAY_SIZE(msi_wmi_keymap) - 1];
 59
 60static struct backlight_device *backlight;
 61
 62static int backlight_map[] = { 0x00, 0x33, 0x66, 0x99, 0xCC, 0xFF };
 63
 64static struct input_dev *msi_wmi_input_dev;
 65
 66static int msi_wmi_query_block(int instance, int *ret)
 67{
 68	acpi_status status;
 69	union acpi_object *obj;
 70
 71	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
 72
 73	status = wmi_query_block(MSIWMI_BIOS_GUID, instance, &output);
 74
 75	obj = output.pointer;
 76
 77	if (!obj || obj->type != ACPI_TYPE_INTEGER) {
 78		if (obj) {
 79			pr_err("query block returned object "
 80			       "type: %d - buffer length:%d\n", obj->type,
 81			       obj->type == ACPI_TYPE_BUFFER ?
 82			       obj->buffer.length : 0);
 83		}
 84		kfree(obj);
 85		return -EINVAL;
 86	}
 87	*ret = obj->integer.value;
 88	kfree(obj);
 89	return 0;
 90}
 91
 92static int msi_wmi_set_block(int instance, int value)
 93{
 94	acpi_status status;
 95
 96	struct acpi_buffer input = { sizeof(int), &value };
 97
 98	pr_debug("Going to set block of instance: %d - value: %d\n",
 99		 instance, value);
100
101	status = wmi_set_block(MSIWMI_BIOS_GUID, instance, &input);
102
103	return ACPI_SUCCESS(status) ? 0 : 1;
104}
105
106static int bl_get(struct backlight_device *bd)
107{
108	int level, err, ret;
109
110	/* Instance 1 is "get backlight", cmp with DSDT */
111	err = msi_wmi_query_block(1, &ret);
112	if (err) {
113		pr_err("Could not query backlight: %d\n", err);
114		return -EINVAL;
115	}
116	pr_debug("Get: Query block returned: %d\n", ret);
117	for (level = 0; level < ARRAY_SIZE(backlight_map); level++) {
118		if (backlight_map[level] == ret) {
119			pr_debug("Current backlight level: 0x%X - index: %d\n",
120				 backlight_map[level], level);
121			break;
122		}
123	}
124	if (level == ARRAY_SIZE(backlight_map)) {
125		pr_err("get: Invalid brightness value: 0x%X\n", ret);
126		return -EINVAL;
127	}
128	return level;
129}
130
131static 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
141static const struct backlight_ops msi_backlight_ops = {
142	.get_brightness	= bl_get,
143	.update_status	= bl_set_status,
144};
145
146static 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		pr_info("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		pr_debug("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					SCANCODE_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				pr_debug("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 - SCANCODE_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				pr_debug("Send key: 0x%X - "
188					 "Input layer keycode: %d\n",
189					 key->code, key->keycode);
190				sparse_keymap_report_entry(msi_wmi_input_dev,
191						key, 1, true);
192			}
193		} else
194			pr_info("Unknown key pressed - %x\n", eventcode);
195	} else
196		pr_info("Unknown event received\n");
197	kfree(response.pointer);
198}
199
200static int __init msi_wmi_input_setup(void)
201{
202	int err;
203
204	msi_wmi_input_dev = input_allocate_device();
205	if (!msi_wmi_input_dev)
206		return -ENOMEM;
207
208	msi_wmi_input_dev->name = "MSI WMI hotkeys";
209	msi_wmi_input_dev->phys = "wmi/input0";
210	msi_wmi_input_dev->id.bustype = BUS_HOST;
211
212	err = sparse_keymap_setup(msi_wmi_input_dev, msi_wmi_keymap, NULL);
213	if (err)
214		goto err_free_dev;
215
216	err = input_register_device(msi_wmi_input_dev);
217
218	if (err)
219		goto err_free_keymap;
220
221	memset(last_pressed, 0, sizeof(last_pressed));
222
223	return 0;
224
225err_free_keymap:
226	sparse_keymap_free(msi_wmi_input_dev);
227err_free_dev:
228	input_free_device(msi_wmi_input_dev);
229	return err;
230}
231
232static int __init msi_wmi_init(void)
233{
234	int err;
235
236	if (!wmi_has_guid(MSIWMI_EVENT_GUID)) {
237		pr_err("This machine doesn't have MSI-hotkeys through WMI\n");
238		return -ENODEV;
239	}
240	err = wmi_install_notify_handler(MSIWMI_EVENT_GUID,
241			msi_wmi_notify, NULL);
242	if (ACPI_FAILURE(err))
243		return -EINVAL;
244
245	err = msi_wmi_input_setup();
246	if (err)
247		goto err_uninstall_notifier;
248
249	if (!acpi_video_backlight_support()) {
250		struct backlight_properties props;
251		memset(&props, 0, sizeof(struct backlight_properties));
252		props.type = BACKLIGHT_PLATFORM;
253		props.max_brightness = ARRAY_SIZE(backlight_map) - 1;
254		backlight = backlight_device_register(DRV_NAME, NULL, NULL,
255						      &msi_backlight_ops,
256						      &props);
257		if (IS_ERR(backlight)) {
258			err = PTR_ERR(backlight);
259			goto err_free_input;
260		}
261
262		err = bl_get(NULL);
263		if (err < 0)
264			goto err_free_backlight;
265
266		backlight->props.brightness = err;
267	}
268	pr_debug("Event handler installed\n");
269
270	return 0;
271
272err_free_backlight:
273	backlight_device_unregister(backlight);
274err_free_input:
275	sparse_keymap_free(msi_wmi_input_dev);
276	input_unregister_device(msi_wmi_input_dev);
277err_uninstall_notifier:
278	wmi_remove_notify_handler(MSIWMI_EVENT_GUID);
279	return err;
280}
281
282static void __exit msi_wmi_exit(void)
283{
284	if (wmi_has_guid(MSIWMI_EVENT_GUID)) {
285		wmi_remove_notify_handler(MSIWMI_EVENT_GUID);
286		sparse_keymap_free(msi_wmi_input_dev);
287		input_unregister_device(msi_wmi_input_dev);
288		backlight_device_unregister(backlight);
289	}
290}
291
292module_init(msi_wmi_init);
293module_exit(msi_wmi_exit);