linux/net/rfkill/input.c
<<
>>
Prefs
   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
  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                mod_delayed_work(system_wq, &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
 174static 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
 190static 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
 198static 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
 223static 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
 255static 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
 272static void rfkill_disconnect(struct input_handle *handle)
 273{
 274        input_close_device(handle);
 275        input_unregister_handle(handle);
 276        kfree(handle);
 277}
 278
 279static 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
 313static 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
 322int __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
 346void __exit rfkill_handler_exit(void)
 347{
 348        input_unregister_handler(&rfkill_handler);
 349        cancel_delayed_work_sync(&rfkill_op_work);
 350}
 351
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.