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 (schedule_delayed_work(&rfkill_op_work, 152 rfkill_ratelimit(rfkill_last_scheduled))) 153 rfkill_last_scheduled = jiffies; 154 } 155 156 static void rfkill_schedule_global_op(enum rfkill_sched_op op) 157 { 158 unsigned long flags; 159 160 spin_lock_irqsave(&rfkill_op_lock, flags); 161 rfkill_op = op; 162 rfkill_op_pending = true; 163 if (op == RFKILL_GLOBAL_OP_EPO && !rfkill_is_epo_lock_active()) { 164 /* bypass the limiter for EPO */ 165 mod_delayed_work(system_wq, &rfkill_op_work, 0); 166 rfkill_last_scheduled = jiffies; 167 } else 168 rfkill_schedule_ratelimited(); 169 spin_unlock_irqrestore(&rfkill_op_lock, flags); 170 } 171 172 static void rfkill_schedule_toggle(enum rfkill_type type) 173 { 174 unsigned long flags; 175 176 if (rfkill_is_epo_lock_active()) 177 return; 178 179 spin_lock_irqsave(&rfkill_op_lock, flags); 180 if (!rfkill_op_pending) { 181 __set_bit(type, rfkill_sw_pending); 182 __change_bit(type, rfkill_sw_state); 183 rfkill_schedule_ratelimited(); 184 } 185 spin_unlock_irqrestore(&rfkill_op_lock, flags); 186 } 187 188 static void rfkill_schedule_evsw_rfkillall(int state) 189 { 190 if (state) 191 rfkill_schedule_global_op(rfkill_master_switch_op); 192 else 193 rfkill_schedule_global_op(RFKILL_GLOBAL_OP_EPO); 194 } 195 196 static void rfkill_event(struct input_handle *handle, unsigned int type, 197 unsigned int code, int data) 198 { 199 if (type == EV_KEY && data == 1) { 200 switch (code) { 201 case KEY_WLAN: 202 rfkill_schedule_toggle(RFKILL_TYPE_WLAN); 203 break; 204 case KEY_BLUETOOTH: 205 rfkill_schedule_toggle(RFKILL_TYPE_BLUETOOTH); 206 break; 207 case KEY_UWB: 208 rfkill_schedule_toggle(RFKILL_TYPE_UWB); 209 break; 210 case KEY_WIMAX: 211 rfkill_schedule_toggle(RFKILL_TYPE_WIMAX); 212 break; 213 case KEY_RFKILL: 214 rfkill_schedule_toggle(RFKILL_TYPE_ALL); 215 break; 216 } 217 } else if (type == EV_SW && code == SW_RFKILL_ALL) 218 rfkill_schedule_evsw_rfkillall(data); 219 } 220 221 static int rfkill_connect(struct input_handler *handler, struct input_dev *dev, 222 const struct input_device_id *id) 223 { 224 struct input_handle *handle; 225 int error; 226 227 handle = kzalloc(sizeof(struct input_handle), GFP_KERNEL); 228 if (!handle) 229 return -ENOMEM; 230 231 handle->dev = dev; 232 handle->handler = handler; 233 handle->name = "rfkill"; 234 235 /* causes rfkill_start() to be called */ 236 error = input_register_handle(handle); 237 if (error) 238 goto err_free_handle; 239 240 error = input_open_device(handle); 241 if (error) 242 goto err_unregister_handle; 243 244 return 0; 245 246 err_unregister_handle: 247 input_unregister_handle(handle); 248 err_free_handle: 249 kfree(handle); 250 return error; 251 } 252 253 static void rfkill_start(struct input_handle *handle) 254 { 255 /* 256 * Take event_lock to guard against configuration changes, we 257 * should be able to deal with concurrency with rfkill_event() 258 * just fine (which event_lock will also avoid). 259 */ 260 spin_lock_irq(&handle->dev->event_lock); 261 262 if (test_bit(EV_SW, handle->dev->evbit) && 263 test_bit(SW_RFKILL_ALL, handle->dev->swbit)) 264 rfkill_schedule_evsw_rfkillall(test_bit(SW_RFKILL_ALL, 265 handle->dev->sw)); 266 267 spin_unlock_irq(&handle->dev->event_lock); 268 } 269 270 static void rfkill_disconnect(struct input_handle *handle) 271 { 272 input_close_device(handle); 273 input_unregister_handle(handle); 274 kfree(handle); 275 } 276 277 static const struct input_device_id rfkill_ids[] = { 278 { 279 .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT, 280 .evbit = { BIT_MASK(EV_KEY) }, 281 .keybit = { [BIT_WORD(KEY_WLAN)] = BIT_MASK(KEY_WLAN) }, 282 }, 283 { 284 .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT, 285 .evbit = { BIT_MASK(EV_KEY) }, 286 .keybit = { [BIT_WORD(KEY_BLUETOOTH)] = BIT_MASK(KEY_BLUETOOTH) }, 287 }, 288 { 289 .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT, 290 .evbit = { BIT_MASK(EV_KEY) }, 291 .keybit = { [BIT_WORD(KEY_UWB)] = BIT_MASK(KEY_UWB) }, 292 }, 293 { 294 .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT, 295 .evbit = { BIT_MASK(EV_KEY) }, 296 .keybit = { [BIT_WORD(KEY_WIMAX)] = BIT_MASK(KEY_WIMAX) }, 297 }, 298 { 299 .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT, 300 .evbit = { BIT_MASK(EV_KEY) }, 301 .keybit = { [BIT_WORD(KEY_RFKILL)] = BIT_MASK(KEY_RFKILL) }, 302 }, 303 { 304 .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_SWBIT, 305 .evbit = { BIT(EV_SW) }, 306 .swbit = { [BIT_WORD(SW_RFKILL_ALL)] = BIT_MASK(SW_RFKILL_ALL) }, 307 }, 308 { } 309 }; 310 311 static struct input_handler rfkill_handler = { 312 .name = "rfkill", 313 .event = rfkill_event, 314 .connect = rfkill_connect, 315 .start = rfkill_start, 316 .disconnect = rfkill_disconnect, 317 .id_table = rfkill_ids, 318 }; 319 320 int __init rfkill_handler_init(void) 321 { 322 switch (rfkill_master_switch_mode) { 323 case RFKILL_INPUT_MASTER_UNBLOCKALL: 324 rfkill_master_switch_op = RFKILL_GLOBAL_OP_UNBLOCK; 325 break; 326 case RFKILL_INPUT_MASTER_RESTORE: 327 rfkill_master_switch_op = RFKILL_GLOBAL_OP_RESTORE; 328 break; 329 case RFKILL_INPUT_MASTER_UNLOCK: 330 rfkill_master_switch_op = RFKILL_GLOBAL_OP_UNLOCK; 331 break; 332 default: 333 return -EINVAL; 334 } 335 336 spin_lock_init(&rfkill_op_lock); 337 338 /* Avoid delay at first schedule */ 339 rfkill_last_scheduled = 340 jiffies - msecs_to_jiffies(RFKILL_OPS_DELAY) - 1; 341 return input_register_handler(&rfkill_handler); 342 } 343 344 void __exit rfkill_handler_exit(void) 345 { 346 input_unregister_handler(&rfkill_handler); 347 cancel_delayed_work_sync(&rfkill_op_work); 348 } 349