projects/linux·blob v3.2 · refs

351 lines · 8.8 KiB

1/*
2 * Input layer to RF Kill interface connector
3 *
4 * Copyright (c) 2007 Dmitry Torokhov
5 * Copyright 2009 Johannes Berg <[email protected]>
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License version 2 as published
9 * by the Free Software Foundation.
10 *
11 * If you ever run into a situation in which you have a SW_ type rfkill
12 * input device, then you can revive code that was removed in the patch
13 * "rfkill-input: remove unused code".
14 */
15
16#include <linux/input.h>
17#include <linux/slab.h>
18#include <linux/moduleparam.h>
19#include <linux/workqueue.h>
20#include <linux/init.h>
21#include <linux/rfkill.h>
22#include <linux/sched.h>
23
24#include "rfkill.h"
25
26enum rfkill_input_master_mode {
27 RFKILL_INPUT_MASTER_UNLOCK = 0,
28 RFKILL_INPUT_MASTER_RESTORE = 1,
29 RFKILL_INPUT_MASTER_UNBLOCKALL = 2,
30 NUM_RFKILL_INPUT_MASTER_MODES
31};
32
33/* Delay (in ms) between consecutive switch ops */
34#define RFKILL_OPS_DELAY 200
35
36static enum rfkill_input_master_mode rfkill_master_switch_mode =
37 RFKILL_INPUT_MASTER_UNBLOCKALL;
38module_param_named(master_switch_mode, rfkill_master_switch_mode, uint, 0);
39MODULE_PARM_DESC(master_switch_mode,
40 "SW_RFKILL_ALL ON should: 0=do nothing (only unlock); 1=restore; 2=unblock all");
41
42static spinlock_t rfkill_op_lock;
43static bool rfkill_op_pending;
44static unsigned long rfkill_sw_pending[BITS_TO_LONGS(NUM_RFKILL_TYPES)];
45static unsigned long rfkill_sw_state[BITS_TO_LONGS(NUM_RFKILL_TYPES)];
46
47enum rfkill_sched_op {
48 RFKILL_GLOBAL_OP_EPO = 0,
49 RFKILL_GLOBAL_OP_RESTORE,
50 RFKILL_GLOBAL_OP_UNLOCK,
51 RFKILL_GLOBAL_OP_UNBLOCK,
52};
53
54static enum rfkill_sched_op rfkill_master_switch_op;
55static enum rfkill_sched_op rfkill_op;
56
57static void __rfkill_handle_global_op(enum rfkill_sched_op op)
58{
59 unsigned int i;
60
61 switch (op) {
62 case RFKILL_GLOBAL_OP_EPO:
63 rfkill_epo();
64 break;
65 case RFKILL_GLOBAL_OP_RESTORE:
66 rfkill_restore_states();
67 break;
68 case RFKILL_GLOBAL_OP_UNLOCK:
69 rfkill_remove_epo_lock();
70 break;
71 case RFKILL_GLOBAL_OP_UNBLOCK:
72 rfkill_remove_epo_lock();
73 for (i = 0; i < NUM_RFKILL_TYPES; i++)
74 rfkill_switch_all(i, false);
75 break;
76 default:
77 /* memory corruption or bug, fail safely */
78 rfkill_epo();
79 WARN(1, "Unknown requested operation %d! "
80 "rfkill Emergency Power Off activated\n",
81 op);
82 }
83}
84
85static void __rfkill_handle_normal_op(const enum rfkill_type type,
86 const bool complement)
87{
88 bool blocked;
89
90 blocked = rfkill_get_global_sw_state(type);
91 if (complement)
92 blocked = !blocked;
93
94 rfkill_switch_all(type, blocked);
95}
96
97static void rfkill_op_handler(struct work_struct *work)
98{
99 unsigned int i;
100 bool c;
101
102 spin_lock_irq(&rfkill_op_lock);
103 do {
104 if (rfkill_op_pending) {
105 enum rfkill_sched_op op = rfkill_op;
106 rfkill_op_pending = false;
107 memset(rfkill_sw_pending, 0,
108 sizeof(rfkill_sw_pending));
109 spin_unlock_irq(&rfkill_op_lock);
110
111 __rfkill_handle_global_op(op);
112
113 spin_lock_irq(&rfkill_op_lock);
114
115 /*
116 * handle global ops first -- during unlocked period
117 * we might have gotten a new global op.
118 */
119 if (rfkill_op_pending)
120 continue;
121 }
122
123 if (rfkill_is_epo_lock_active())
124 continue;
125
126 for (i = 0; i < NUM_RFKILL_TYPES; i++) {
127 if (__test_and_clear_bit(i, rfkill_sw_pending)) {
128 c = __test_and_clear_bit(i, rfkill_sw_state);
129 spin_unlock_irq(&rfkill_op_lock);
130
131 __rfkill_handle_normal_op(i, c);
132
133 spin_lock_irq(&rfkill_op_lock);
134 }
135 }
136 } while (rfkill_op_pending);
137 spin_unlock_irq(&rfkill_op_lock);
138}
139
140static DECLARE_DELAYED_WORK(rfkill_op_work, rfkill_op_handler);
141static unsigned long rfkill_last_scheduled;
142
143static unsigned long rfkill_ratelimit(const unsigned long last)
144{
145 const unsigned long delay = msecs_to_jiffies(RFKILL_OPS_DELAY);
146 return time_after(jiffies, last + delay) ? 0 : delay;
147}
148
149static void rfkill_schedule_ratelimited(void)
150{
151 if (delayed_work_pending(&rfkill_op_work))
152 return;
153 schedule_delayed_work(&rfkill_op_work,
154 rfkill_ratelimit(rfkill_last_scheduled));
155 rfkill_last_scheduled = jiffies;
156}
157
158static void rfkill_schedule_global_op(enum rfkill_sched_op op)
159{
160 unsigned long flags;
161
162 spin_lock_irqsave(&rfkill_op_lock, flags);
163 rfkill_op = op;
164 rfkill_op_pending = true;
165 if (op == RFKILL_GLOBAL_OP_EPO && !rfkill_is_epo_lock_active()) {
166 /* bypass the limiter for EPO */
167 cancel_delayed_work(&rfkill_op_work);
168 schedule_delayed_work(&rfkill_op_work, 0);
169 rfkill_last_scheduled = jiffies;
170 } else
171 rfkill_schedule_ratelimited();
172 spin_unlock_irqrestore(&rfkill_op_lock, flags);
173}
174
175static void rfkill_schedule_toggle(enum rfkill_type type)
176{
177 unsigned long flags;
178
179 if (rfkill_is_epo_lock_active())
180 return;
181
182 spin_lock_irqsave(&rfkill_op_lock, flags);
183 if (!rfkill_op_pending) {
184 __set_bit(type, rfkill_sw_pending);
185 __change_bit(type, rfkill_sw_state);
186 rfkill_schedule_ratelimited();
187 }
188 spin_unlock_irqrestore(&rfkill_op_lock, flags);
189}
190
191static void rfkill_schedule_evsw_rfkillall(int state)
192{
193 if (state)
194 rfkill_schedule_global_op(rfkill_master_switch_op);
195 else
196 rfkill_schedule_global_op(RFKILL_GLOBAL_OP_EPO);
197}
198
199static void rfkill_event(struct input_handle *handle, unsigned int type,
200 unsigned int code, int data)
201{
202 if (type == EV_KEY && data == 1) {
203 switch (code) {
204 case KEY_WLAN:
205 rfkill_schedule_toggle(RFKILL_TYPE_WLAN);
206 break;
207 case KEY_BLUETOOTH:
208 rfkill_schedule_toggle(RFKILL_TYPE_BLUETOOTH);
209 break;
210 case KEY_UWB:
211 rfkill_schedule_toggle(RFKILL_TYPE_UWB);
212 break;
213 case KEY_WIMAX:
214 rfkill_schedule_toggle(RFKILL_TYPE_WIMAX);
215 break;
216 case KEY_RFKILL:
217 rfkill_schedule_toggle(RFKILL_TYPE_ALL);
218 break;
219 }
220 } else if (type == EV_SW && code == SW_RFKILL_ALL)
221 rfkill_schedule_evsw_rfkillall(data);
222}
223
224static int rfkill_connect(struct input_handler *handler, struct input_dev *dev,
225 const struct input_device_id *id)
226{
227 struct input_handle *handle;
228 int error;
229
230 handle = kzalloc(sizeof(struct input_handle), GFP_KERNEL);
231 if (!handle)
232 return -ENOMEM;
233
234 handle->dev = dev;
235 handle->handler = handler;
236 handle->name = "rfkill";
237
238 /* causes rfkill_start() to be called */
239 error = input_register_handle(handle);
240 if (error)
241 goto err_free_handle;
242
243 error = input_open_device(handle);
244 if (error)
245 goto err_unregister_handle;
246
247 return 0;
248
249 err_unregister_handle:
250 input_unregister_handle(handle);
251 err_free_handle:
252 kfree(handle);
253 return error;
254}
255
256static void rfkill_start(struct input_handle *handle)
257{
258 /*
259 * Take event_lock to guard against configuration changes, we
260 * should be able to deal with concurrency with rfkill_event()
261 * just fine (which event_lock will also avoid).
262 */
263 spin_lock_irq(&handle->dev->event_lock);
264
265 if (test_bit(EV_SW, handle->dev->evbit) &&
266 test_bit(SW_RFKILL_ALL, handle->dev->swbit))
267 rfkill_schedule_evsw_rfkillall(test_bit(SW_RFKILL_ALL,
268 handle->dev->sw));
269
270 spin_unlock_irq(&handle->dev->event_lock);
271}
272
273static void rfkill_disconnect(struct input_handle *handle)
274{
275 input_close_device(handle);
276 input_unregister_handle(handle);
277 kfree(handle);
278}
279
280static const struct input_device_id rfkill_ids[] = {
281 {
282 .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT,
283 .evbit = { BIT_MASK(EV_KEY) },
284 .keybit = { [BIT_WORD(KEY_WLAN)] = BIT_MASK(KEY_WLAN) },
285 },
286 {
287 .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT,
288 .evbit = { BIT_MASK(EV_KEY) },
289 .keybit = { [BIT_WORD(KEY_BLUETOOTH)] = BIT_MASK(KEY_BLUETOOTH) },
290 },
291 {
292 .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT,
293 .evbit = { BIT_MASK(EV_KEY) },
294 .keybit = { [BIT_WORD(KEY_UWB)] = BIT_MASK(KEY_UWB) },
295 },
296 {
297 .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT,
298 .evbit = { BIT_MASK(EV_KEY) },
299 .keybit = { [BIT_WORD(KEY_WIMAX)] = BIT_MASK(KEY_WIMAX) },
300 },
301 {
302 .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT,
303 .evbit = { BIT_MASK(EV_KEY) },
304 .keybit = { [BIT_WORD(KEY_RFKILL)] = BIT_MASK(KEY_RFKILL) },
305 },
306 {
307 .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_SWBIT,
308 .evbit = { BIT(EV_SW) },
309 .swbit = { [BIT_WORD(SW_RFKILL_ALL)] = BIT_MASK(SW_RFKILL_ALL) },
310 },
311 { }
312};
313
314static struct input_handler rfkill_handler = {
315 .name = "rfkill",
316 .event = rfkill_event,
317 .connect = rfkill_connect,
318 .start = rfkill_start,
319 .disconnect = rfkill_disconnect,
320 .id_table = rfkill_ids,
321};
322
323int __init rfkill_handler_init(void)
324{
325 switch (rfkill_master_switch_mode) {
326 case RFKILL_INPUT_MASTER_UNBLOCKALL:
327 rfkill_master_switch_op = RFKILL_GLOBAL_OP_UNBLOCK;
328 break;
329 case RFKILL_INPUT_MASTER_RESTORE:
330 rfkill_master_switch_op = RFKILL_GLOBAL_OP_RESTORE;
331 break;
332 case RFKILL_INPUT_MASTER_UNLOCK:
333 rfkill_master_switch_op = RFKILL_GLOBAL_OP_UNLOCK;
334 break;
335 default:
336 return -EINVAL;
337 }
338
339 spin_lock_init(&rfkill_op_lock);
340
341 /* Avoid delay at first schedule */
342 rfkill_last_scheduled =
343 jiffies - msecs_to_jiffies(RFKILL_OPS_DELAY) - 1;
344 return input_register_handler(&rfkill_handler);
345}
346
347void __exit rfkill_handler_exit(void)
348{
349 input_unregister_handler(&rfkill_handler);
350 cancel_delayed_work_sync(&rfkill_op_work);
351}