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