Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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kernel
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linux
1/*
2 * Input layer to RF Kill interface connector
3 *
4 * Copyright (c) 2007 Dmitry Torokhov
5 */
6
7/*
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License version 2 as published
10 * by the Free Software Foundation.
11 */
12
13#include <linux/module.h>
14#include <linux/input.h>
15#include <linux/slab.h>
16#include <linux/workqueue.h>
17#include <linux/init.h>
18#include <linux/rfkill.h>
19
20MODULE_AUTHOR("Dmitry Torokhov <dtor@mail.ru>");
21MODULE_DESCRIPTION("Input layer to RF switch connector");
22MODULE_LICENSE("GPL");
23
24struct rfkill_task {
25 struct work_struct work;
26 enum rfkill_type type;
27 struct mutex mutex; /* ensures that task is serialized */
28 spinlock_t lock; /* for accessing last and desired state */
29 unsigned long last; /* last schedule */
30 enum rfkill_state desired_state; /* on/off */
31 enum rfkill_state current_state; /* on/off */
32};
33
34static void rfkill_task_handler(struct work_struct *work)
35{
36 struct rfkill_task *task = container_of(work, struct rfkill_task, work);
37 enum rfkill_state state;
38
39 mutex_lock(&task->mutex);
40
41 /*
42 * Use temp variable to fetch desired state to keep it
43 * consistent even if rfkill_schedule_toggle() runs in
44 * another thread or interrupts us.
45 */
46 state = task->desired_state;
47
48 if (state != task->current_state) {
49 rfkill_switch_all(task->type, state);
50 task->current_state = state;
51 }
52
53 mutex_unlock(&task->mutex);
54}
55
56static void rfkill_schedule_toggle(struct rfkill_task *task)
57{
58 unsigned long flags;
59
60 spin_lock_irqsave(&task->lock, flags);
61
62 if (time_after(jiffies, task->last + msecs_to_jiffies(200))) {
63 task->desired_state = !task->desired_state;
64 task->last = jiffies;
65 schedule_work(&task->work);
66 }
67
68 spin_unlock_irqrestore(&task->lock, flags);
69}
70
71#define DEFINE_RFKILL_TASK(n, t) \
72 struct rfkill_task n = { \
73 .work = __WORK_INITIALIZER(n.work, \
74 rfkill_task_handler), \
75 .type = t, \
76 .mutex = __MUTEX_INITIALIZER(n.mutex), \
77 .lock = __SPIN_LOCK_UNLOCKED(n.lock), \
78 .desired_state = RFKILL_STATE_ON, \
79 .current_state = RFKILL_STATE_ON, \
80 }
81
82static DEFINE_RFKILL_TASK(rfkill_wlan, RFKILL_TYPE_WLAN);
83static DEFINE_RFKILL_TASK(rfkill_bt, RFKILL_TYPE_BLUETOOTH);
84
85static void rfkill_event(struct input_handle *handle, unsigned int type,
86 unsigned int code, int down)
87{
88 if (type == EV_KEY && down == 1) {
89 switch (code) {
90 case KEY_WLAN:
91 rfkill_schedule_toggle(&rfkill_wlan);
92 break;
93 case KEY_BLUETOOTH:
94 rfkill_schedule_toggle(&rfkill_bt);
95 break;
96 default:
97 break;
98 }
99 }
100}
101
102static int rfkill_connect(struct input_handler *handler, struct input_dev *dev,
103 const struct input_device_id *id)
104{
105 struct input_handle *handle;
106 int error;
107
108 handle = kzalloc(sizeof(struct input_handle), GFP_KERNEL);
109 if (!handle)
110 return -ENOMEM;
111
112 handle->dev = dev;
113 handle->handler = handler;
114 handle->name = "rfkill";
115
116 error = input_register_handle(handle);
117 if (error)
118 goto err_free_handle;
119
120 error = input_open_device(handle);
121 if (error)
122 goto err_unregister_handle;
123
124 return 0;
125
126 err_unregister_handle:
127 input_unregister_handle(handle);
128 err_free_handle:
129 kfree(handle);
130 return error;
131}
132
133static void rfkill_disconnect(struct input_handle *handle)
134{
135 input_close_device(handle);
136 input_unregister_handle(handle);
137 kfree(handle);
138}
139
140static const struct input_device_id rfkill_ids[] = {
141 {
142 .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT,
143 .evbit = { BIT(EV_KEY) },
144 .keybit = { [LONG(KEY_WLAN)] = BIT(KEY_WLAN) },
145 },
146 {
147 .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT,
148 .evbit = { BIT(EV_KEY) },
149 .keybit = { [LONG(KEY_BLUETOOTH)] = BIT(KEY_BLUETOOTH) },
150 },
151 { }
152};
153
154static struct input_handler rfkill_handler = {
155 .event = rfkill_event,
156 .connect = rfkill_connect,
157 .disconnect = rfkill_disconnect,
158 .name = "rfkill",
159 .id_table = rfkill_ids,
160};
161
162static int __init rfkill_handler_init(void)
163{
164 return input_register_handler(&rfkill_handler);
165}
166
167static void __exit rfkill_handler_exit(void)
168{
169 input_unregister_handler(&rfkill_handler);
170 flush_scheduled_work();
171}
172
173module_init(rfkill_handler_init);
174module_exit(rfkill_handler_exit);