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

  1/*
  2 * Dell WMI hotkeys
  3 *
  4 * Copyright (C) 2008 Red Hat <mjg@redhat.com>
  5 *
  6 * Portions based on wistron_btns.c:
  7 * Copyright (C) 2005 Miloslav Trmac <mitr@volny.cz>
  8 * Copyright (C) 2005 Bernhard Rosenkraenzer <bero@arklinux.org>
  9 * Copyright (C) 2005 Dmitry Torokhov <dtor@mail.ru>
 10 *
 11 *  This program is free software; you can redistribute it and/or modify
 12 *  it under the terms of the GNU General Public License as published by
 13 *  the Free Software Foundation; either version 2 of the License, or
 14 *  (at your option) any later version.
 15 *
 16 *  This program is distributed in the hope that it will be useful,
 17 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 18 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 19 *  GNU General Public License for more details.
 20 *
 21 *  You should have received a copy of the GNU General Public License
 22 *  along with this program; if not, write to the Free Software
 23 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 24 */
 25
 26#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 27
 28#include <linux/kernel.h>
 29#include <linux/module.h>
 30#include <linux/init.h>
 31#include <linux/slab.h>
 32#include <linux/types.h>
 33#include <linux/input.h>
 34#include <linux/input/sparse-keymap.h>
 35#include <acpi/acpi_drivers.h>
 36#include <linux/acpi.h>
 37#include <linux/string.h>
 38#include <linux/dmi.h>
 39
 40MODULE_AUTHOR("Matthew Garrett <mjg@redhat.com>");
 41MODULE_DESCRIPTION("Dell laptop WMI hotkeys driver");
 42MODULE_LICENSE("GPL");
 43
 44#define DELL_EVENT_GUID "9DBB5994-A997-11DA-B012-B622A1EF5492"
 45
 46static int acpi_video;
 47
 48MODULE_ALIAS("wmi:"DELL_EVENT_GUID);
 49
 50/*
 51 * Certain keys are flagged as KE_IGNORE. All of these are either
 52 * notifications (rather than requests for change) or are also sent
 53 * via the keyboard controller so should not be sent again.
 54 */
 55
 56static const struct key_entry dell_wmi_legacy_keymap[] __initconst = {
 57	{ KE_KEY, 0xe045, { KEY_PROG1 } },
 58	{ KE_KEY, 0xe009, { KEY_EJECTCD } },
 59
 60	/* These also contain the brightness level at offset 6 */
 61	{ KE_KEY, 0xe006, { KEY_BRIGHTNESSUP } },
 62	{ KE_KEY, 0xe005, { KEY_BRIGHTNESSDOWN } },
 63
 64	/* Battery health status button */
 65	{ KE_KEY, 0xe007, { KEY_BATTERY } },
 66
 67	/* This is actually for all radios. Although physically a
 68	 * switch, the notification does not provide an indication of
 69	 * state and so it should be reported as a key */
 70	{ KE_KEY, 0xe008, { KEY_WLAN } },
 71
 72	/* The next device is at offset 6, the active devices are at
 73	   offset 8 and the attached devices at offset 10 */
 74	{ KE_KEY, 0xe00b, { KEY_SWITCHVIDEOMODE } },
 75
 76	{ KE_IGNORE, 0xe00c, { KEY_KBDILLUMTOGGLE } },
 77
 78	/* BIOS error detected */
 79	{ KE_IGNORE, 0xe00d, { KEY_RESERVED } },
 80
 81	/* Wifi Catcher */
 82	{ KE_KEY, 0xe011, {KEY_PROG2 } },
 83
 84	/* Ambient light sensor toggle */
 85	{ KE_IGNORE, 0xe013, { KEY_RESERVED } },
 86
 87	{ KE_IGNORE, 0xe020, { KEY_MUTE } },
 88	{ KE_IGNORE, 0xe02e, { KEY_VOLUMEDOWN } },
 89	{ KE_IGNORE, 0xe030, { KEY_VOLUMEUP } },
 90	{ KE_IGNORE, 0xe033, { KEY_KBDILLUMUP } },
 91	{ KE_IGNORE, 0xe034, { KEY_KBDILLUMDOWN } },
 92	{ KE_IGNORE, 0xe03a, { KEY_CAPSLOCK } },
 93	{ KE_IGNORE, 0xe045, { KEY_NUMLOCK } },
 94	{ KE_IGNORE, 0xe046, { KEY_SCROLLLOCK } },
 95	{ KE_END, 0 }
 96};
 97
 98static bool dell_new_hk_type;
 99
100struct dell_bios_keymap_entry {
101	u16 scancode;
102	u16 keycode;
103};
104
105struct dell_bios_hotkey_table {
106	struct dmi_header header;
107	struct dell_bios_keymap_entry keymap[];
108
109};
110
111static const struct dell_bios_hotkey_table *dell_bios_hotkey_table;
112
113static const u16 bios_to_linux_keycode[256] __initconst = {
114
115	KEY_MEDIA,	KEY_NEXTSONG,	KEY_PLAYPAUSE, KEY_PREVIOUSSONG,
116	KEY_STOPCD,	KEY_UNKNOWN,	KEY_UNKNOWN,	KEY_UNKNOWN,
117	KEY_WWW,	KEY_UNKNOWN,	KEY_VOLUMEDOWN, KEY_MUTE,
118	KEY_VOLUMEUP,	KEY_UNKNOWN,	KEY_BATTERY,	KEY_EJECTCD,
119	KEY_UNKNOWN,	KEY_SLEEP,	KEY_PROG1, KEY_BRIGHTNESSDOWN,
120	KEY_BRIGHTNESSUP,	KEY_UNKNOWN,	KEY_KBDILLUMTOGGLE,
121	KEY_UNKNOWN,	KEY_SWITCHVIDEOMODE,	KEY_UNKNOWN, KEY_UNKNOWN,
122	KEY_SWITCHVIDEOMODE,	KEY_UNKNOWN,	KEY_UNKNOWN, KEY_PROG2,
123	KEY_UNKNOWN, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
124	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
125	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
126	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
127	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
128	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
129	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
130	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
131	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
132	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
133	KEY_PROG3
134};
135
136static struct input_dev *dell_wmi_input_dev;
137
138static void dell_wmi_notify(u32 value, void *context)
139{
140	struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
141	union acpi_object *obj;
142	acpi_status status;
143
144	status = wmi_get_event_data(value, &response);
145	if (status != AE_OK) {
146		pr_info("bad event status 0x%x\n", status);
147		return;
148	}
149
150	obj = (union acpi_object *)response.pointer;
151
152	if (obj && obj->type == ACPI_TYPE_BUFFER) {
153		const struct key_entry *key;
154		int reported_key;
155		u16 *buffer_entry = (u16 *)obj->buffer.pointer;
156
157		if (dell_new_hk_type && (buffer_entry[1] != 0x10)) {
158			pr_info("Received unknown WMI event (0x%x)\n",
159				buffer_entry[1]);
160			kfree(obj);
161			return;
162		}
163
164		if (dell_new_hk_type || buffer_entry[1] == 0x0)
165			reported_key = (int)buffer_entry[2];
166		else
167			reported_key = (int)buffer_entry[1] & 0xffff;
168
169		key = sparse_keymap_entry_from_scancode(dell_wmi_input_dev,
170							reported_key);
171		if (!key) {
172			pr_info("Unknown key %x pressed\n", reported_key);
173		} else if ((key->keycode == KEY_BRIGHTNESSUP ||
174			    key->keycode == KEY_BRIGHTNESSDOWN) && acpi_video) {
175			/* Don't report brightness notifications that will also
176			 * come via ACPI */
177			;
178		} else {
179			sparse_keymap_report_entry(dell_wmi_input_dev, key,
180						   1, true);
181		}
182	}
183	kfree(obj);
184}
185
186static const struct key_entry * __init dell_wmi_prepare_new_keymap(void)
187{
188	int hotkey_num = (dell_bios_hotkey_table->header.length - 4) /
189				sizeof(struct dell_bios_keymap_entry);
190	struct key_entry *keymap;
191	int i;
192
193	keymap = kcalloc(hotkey_num + 1, sizeof(struct key_entry), GFP_KERNEL);
194	if (!keymap)
195		return NULL;
196
197	for (i = 0; i < hotkey_num; i++) {
198		const struct dell_bios_keymap_entry *bios_entry =
199					&dell_bios_hotkey_table->keymap[i];
200		keymap[i].type = KE_KEY;
201		keymap[i].code = bios_entry->scancode;
202		keymap[i].keycode = bios_entry->keycode < 256 ?
203				    bios_to_linux_keycode[bios_entry->keycode] :
204				    KEY_RESERVED;
205	}
206
207	keymap[hotkey_num].type = KE_END;
208
209	return keymap;
210}
211
212static int __init dell_wmi_input_setup(void)
213{
214	int err;
215
216	dell_wmi_input_dev = input_allocate_device();
217	if (!dell_wmi_input_dev)
218		return -ENOMEM;
219
220	dell_wmi_input_dev->name = "Dell WMI hotkeys";
221	dell_wmi_input_dev->phys = "wmi/input0";
222	dell_wmi_input_dev->id.bustype = BUS_HOST;
223
224	if (dell_new_hk_type) {
225		const struct key_entry *keymap = dell_wmi_prepare_new_keymap();
226		if (!keymap) {
227			err = -ENOMEM;
228			goto err_free_dev;
229		}
230
231		err = sparse_keymap_setup(dell_wmi_input_dev, keymap, NULL);
232
233		/*
234		 * Sparse keymap library makes a copy of keymap so we
235		 * don't need the original one that was allocated.
236		 */
237		kfree(keymap);
238	} else {
239		err = sparse_keymap_setup(dell_wmi_input_dev,
240					  dell_wmi_legacy_keymap, NULL);
241	}
242	if (err)
243		goto err_free_dev;
244
245	err = input_register_device(dell_wmi_input_dev);
246	if (err)
247		goto err_free_keymap;
248
249	return 0;
250
251 err_free_keymap:
252	sparse_keymap_free(dell_wmi_input_dev);
253 err_free_dev:
254	input_free_device(dell_wmi_input_dev);
255	return err;
256}
257
258static void dell_wmi_input_destroy(void)
259{
260	sparse_keymap_free(dell_wmi_input_dev);
261	input_unregister_device(dell_wmi_input_dev);
262}
263
264static void __init find_hk_type(const struct dmi_header *dm, void *dummy)
265{
266	if (dm->type == 0xb2 && dm->length > 6) {
267		dell_new_hk_type = true;
268		dell_bios_hotkey_table =
269			container_of(dm, struct dell_bios_hotkey_table, header);
270	}
271}
272
273static int __init dell_wmi_init(void)
274{
275	int err;
276	acpi_status status;
277
278	if (!wmi_has_guid(DELL_EVENT_GUID)) {
279		pr_warn("No known WMI GUID found\n");
280		return -ENODEV;
281	}
282
283	dmi_walk(find_hk_type, NULL);
284	acpi_video = acpi_video_backlight_support();
285
286	err = dell_wmi_input_setup();
287	if (err)
288		return err;
289
290	status = wmi_install_notify_handler(DELL_EVENT_GUID,
291					 dell_wmi_notify, NULL);
292	if (ACPI_FAILURE(status)) {
293		dell_wmi_input_destroy();
294		pr_err("Unable to register notify handler - %d\n", status);
295		return -ENODEV;
296	}
297
298	return 0;
299}
300module_init(dell_wmi_init);
301
302static void __exit dell_wmi_exit(void)
303{
304	wmi_remove_notify_handler(DELL_EVENT_GUID);
305	dell_wmi_input_destroy();
306}
307module_exit(dell_wmi_exit);