1 /* 2 * Input layer to RF Kill interface connector 3 * 4 * Copyright (c) 2007 Dmitry Torokhov 5 * Copyright 2009 Johannes Berg <johannes@sipsolutions.net> 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 26 enum 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 36 static enum rfkill_input_master_mode rfkill_master_switch_mode = 37 RFKILL_INPUT_MASTER_UNBLOCKALL; 38 module_param_named(master_switch_mode, rfkill_master_switch_mode, uint, 0); 39 MODULE_PARM_DESC(master_switch_mode, 40 "SW_RFKILL_ALL ON should: 0=do nothing (only unlock); 1=restore; 2=unblock all"); 41 42 static spinlock_t rfkill_op_lock; 43 static bool rfkill_op_pending; 44 static unsigned long rfkill_sw_pending[BITS_TO_LONGS(NUM_RFKILL_TYPES)]; 45 static unsigned long rfkill_sw_state[BITS_TO_LONGS(NUM_RFKILL_TYPES)]; 46 47 enum 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 54 static enum rfkill_sched_op rfkill_master_switch_op; 55 static enum rfkill_sched_op rfkill_op; 56 57 static 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 85 static 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 97 static 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 } 139 140 static DECLARE_DELAYED_WORK(rfkill_op_work, rfkill_op_handler); 141 static unsigned long rfkill_last_scheduled; 142 143 static 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 } 148 149 static 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 } 157 158 static 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 } 174 175 static 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 } 190 191 static 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 } 198 199 static 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 } 223 224 static 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 } 255 256 static 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 } 272 273 static void rfkill_disconnect(struct input_handle *handle) 274 { 275 input_close_device(handle); 276 input_unregister_handle(handle); 277 kfree(handle); 278 } 279 280 static 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 }; 313 314 static 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 }; 322 323 int __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 } 346 347 void __exit rfkill_handler_exit(void) 348 { 349 input_unregister_handler(&rfkill_handler); 350 cancel_delayed_work_sync(&rfkill_op_work); 351 } 352