net/rfkill/rfkill.c

   1 /*
   2  * Copyright (C) 2006 - 2007 Ivo van Doorn
   3  * Copyright (C) 2007 Dmitry Torokhov
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the
  17  * Free Software Foundation, Inc.,
  18  * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19  */
  20
  21 #include <linux/kernel.h>
  22 #include <linux/module.h>
  23 #include <linux/init.h>
  24 #include <linux/workqueue.h>
  25 #include <linux/capability.h>
  26 #include <linux/list.h>
  27 #include <linux/mutex.h>
  28 #include <linux/rfkill.h>
  29
  30 /* Get declaration of rfkill_switch_all() to shut up sparse. */
  31 #include "rfkill-input.h"
  32
  33
  34 MODULE_AUTHOR("Ivo van Doorn <IvDoorn@gmail.com>");
  35 MODULE_VERSION("1.0");
  36 MODULE_DESCRIPTION("RF switch support");
  37 MODULE_LICENSE("GPL");
  38
  39 static LIST_HEAD(rfkill_list);  /* list of registered rf switches */
  40 static DEFINE_MUTEX(rfkill_mutex);
  41
  42 static enum rfkill_state rfkill_states[RFKILL_TYPE_MAX];
  43
  44
  45 static void rfkill_led_trigger(struct rfkill *rfkill,
  46                                enum rfkill_state state)
  47 {
  48 #ifdef CONFIG_RFKILL_LEDS
  49         struct led_trigger *led = &rfkill->led_trigger;
  50
  51         if (!led->name)
  52                 return;
  53         if (state == RFKILL_STATE_OFF)
  54                 led_trigger_event(led, LED_OFF);
  55         else
  56                 led_trigger_event(led, LED_FULL);
  57 #endif /* CONFIG_RFKILL_LEDS */
  58 }
  59
  60 static int rfkill_toggle_radio(struct rfkill *rfkill,
  61                                 enum rfkill_state state)
  62 {
  63         int retval = 0;
  64
  65         if (state != rfkill->state) {
  66                 retval = rfkill->toggle_radio(rfkill->data, state);
  67                 if (!retval) {
  68                         rfkill->state = state;
  69                         rfkill_led_trigger(rfkill, state);
  70                 }
  71         }
  72
  73         return retval;
  74 }
  75
  76 /**
  77  * rfkill_switch_all - Toggle state of all switches of given type
  78  * @type: type of interfaces to be affeceted
  79  * @state: the new state
  80  *
  81  * This function toggles state of all switches of given type unless
  82  * a specific switch is claimed by userspace in which case it is
  83  * left alone.
  84  */
  85
  86 void rfkill_switch_all(enum rfkill_type type, enum rfkill_state state)
  87 {
  88         struct rfkill *rfkill;
  89
  90         mutex_lock(&rfkill_mutex);
  91
  92         rfkill_states[type] = state;
  93
  94         list_for_each_entry(rfkill, &rfkill_list, node) {
  95                 if (!rfkill->user_claim)
  96                         rfkill_toggle_radio(rfkill, state);
  97         }
  98
  99         mutex_unlock(&rfkill_mutex);
 100 }
 101 EXPORT_SYMBOL(rfkill_switch_all);
 102
 103 static ssize_t rfkill_name_show(struct device *dev,
 104                                 struct device_attribute *attr,
 105                                 char *buf)
 106 {
 107         struct rfkill *rfkill = to_rfkill(dev);
 108
 109         return sprintf(buf, "%s\n", rfkill->name);
 110 }
 111
 112 static ssize_t rfkill_type_show(struct device *dev,
 113                                 struct device_attribute *attr,
 114                                 char *buf)
 115 {
 116         struct rfkill *rfkill = to_rfkill(dev);
 117         const char *type;
 118
 119         switch (rfkill->type) {
 120         case RFKILL_TYPE_WLAN:
 121                 type = "wlan";
 122                 break;
 123         case RFKILL_TYPE_BLUETOOTH:
 124                 type = "bluetooth";
 125                 break;
 126         case RFKILL_TYPE_UWB:
 127                 type = "ultrawideband";
 128                 break;
 129         case RFKILL_TYPE_WIMAX:
 130                 type = "wimax";
 131                 break;
 132         default:
 133                 BUG();
 134         }
 135
 136         return sprintf(buf, "%s\n", type);
 137 }
 138
 139 static ssize_t rfkill_state_show(struct device *dev,
 140                                  struct device_attribute *attr,
 141                                  char *buf)
 142 {
 143         struct rfkill *rfkill = to_rfkill(dev);
 144
 145         return sprintf(buf, "%d\n", rfkill->state);
 146 }
 147
 148 static ssize_t rfkill_state_store(struct device *dev,
 149                                   struct device_attribute *attr,
 150                                   const char *buf, size_t count)
 151 {
 152         struct rfkill *rfkill = to_rfkill(dev);
 153         unsigned int state = simple_strtoul(buf, NULL, 0);
 154         int error;
 155
 156         if (!capable(CAP_NET_ADMIN))
 157                 return -EPERM;
 158
 159         if (mutex_lock_interruptible(&rfkill->mutex))
 160                 return -ERESTARTSYS;
 161         error = rfkill_toggle_radio(rfkill,
 162                         state ? RFKILL_STATE_ON : RFKILL_STATE_OFF);
 163         mutex_unlock(&rfkill->mutex);
 164
 165         return error ? error : count;
 166 }
 167
 168 static ssize_t rfkill_claim_show(struct device *dev,
 169                                  struct device_attribute *attr,
 170                                  char *buf)
 171 {
 172         struct rfkill *rfkill = to_rfkill(dev);
 173
 174         return sprintf(buf, "%d", rfkill->user_claim);
 175 }
 176
 177 static ssize_t rfkill_claim_store(struct device *dev,
 178                                   struct device_attribute *attr,
 179                                   const char *buf, size_t count)
 180 {
 181         struct rfkill *rfkill = to_rfkill(dev);
 182         bool claim = !!simple_strtoul(buf, NULL, 0);
 183         int error;
 184
 185         if (!capable(CAP_NET_ADMIN))
 186                 return -EPERM;
 187
 188         /*
 189          * Take the global lock to make sure the kernel is not in
 190          * the middle of rfkill_switch_all
 191          */
 192         error = mutex_lock_interruptible(&rfkill_mutex);
 193         if (error)
 194                 return error;
 195
 196         if (rfkill->user_claim_unsupported) {
 197                 error = -EOPNOTSUPP;
 198                 goto out_unlock;
 199         }
 200         if (rfkill->user_claim != claim) {
 201                 if (!claim)
 202                         rfkill_toggle_radio(rfkill,
 203                                             rfkill_states[rfkill->type]);
 204                 rfkill->user_claim = claim;
 205         }
 206
 207 out_unlock:
 208         mutex_unlock(&rfkill_mutex);
 209
 210         return error ? error : count;
 211 }
 212
 213 static struct device_attribute rfkill_dev_attrs[] = {
 214         __ATTR(name, S_IRUGO, rfkill_name_show, NULL),
 215         __ATTR(type, S_IRUGO, rfkill_type_show, NULL),
 216         __ATTR(state, S_IRUGO|S_IWUSR, rfkill_state_show, rfkill_state_store),
 217         __ATTR(claim, S_IRUGO|S_IWUSR, rfkill_claim_show, rfkill_claim_store),
 218         __ATTR_NULL
 219 };
 220
 221 static void rfkill_release(struct device *dev)
 222 {
 223         struct rfkill *rfkill = to_rfkill(dev);
 224
 225         kfree(rfkill);
 226         module_put(THIS_MODULE);
 227 }
 228
 229 #ifdef CONFIG_PM
 230 static int rfkill_suspend(struct device *dev, pm_message_t state)
 231 {
 232         struct rfkill *rfkill = to_rfkill(dev);
 233
 234         if (dev->power.power_state.event != state.event) {
 235 <<<<<<< HEAD:net/rfkill/rfkill.c
 236                 if (state.event == PM_EVENT_SUSPEND) {
 237 =======
 238                 if (state.event & PM_EVENT_SLEEP) {
 239 >>>>>>> 264e3e889d86e552b4191d69bb60f4f3b383135a:net/rfkill/rfkill.c
 240                         mutex_lock(&rfkill->mutex);
 241
 242                         if (rfkill->state == RFKILL_STATE_ON)
 243                                 rfkill->toggle_radio(rfkill->data,
 244                                                      RFKILL_STATE_OFF);
 245
 246                         mutex_unlock(&rfkill->mutex);
 247                 }
 248
 249                 dev->power.power_state = state;
 250         }
 251
 252         return 0;
 253 }
 254
 255 static int rfkill_resume(struct device *dev)
 256 {
 257         struct rfkill *rfkill = to_rfkill(dev);
 258
 259         if (dev->power.power_state.event != PM_EVENT_ON) {
 260                 mutex_lock(&rfkill->mutex);
 261
 262                 if (rfkill->state == RFKILL_STATE_ON)
 263                         rfkill->toggle_radio(rfkill->data, RFKILL_STATE_ON);
 264
 265                 mutex_unlock(&rfkill->mutex);
 266         }
 267
 268         dev->power.power_state = PMSG_ON;
 269         return 0;
 270 }
 271 #else
 272 #define rfkill_suspend NULL
 273 #define rfkill_resume NULL
 274 #endif
 275
 276 static struct class rfkill_class = {
 277         .name           = "rfkill",
 278         .dev_release    = rfkill_release,
 279         .dev_attrs      = rfkill_dev_attrs,
 280         .suspend        = rfkill_suspend,
 281         .resume         = rfkill_resume,
 282 };
 283
 284 static int rfkill_add_switch(struct rfkill *rfkill)
 285 {
 286         int error;
 287
 288         mutex_lock(&rfkill_mutex);
 289
 290         error = rfkill_toggle_radio(rfkill, rfkill_states[rfkill->type]);
 291         if (!error)
 292                 list_add_tail(&rfkill->node, &rfkill_list);
 293
 294         mutex_unlock(&rfkill_mutex);
 295
 296         return error;
 297 }
 298
 299 static void rfkill_remove_switch(struct rfkill *rfkill)
 300 {
 301         mutex_lock(&rfkill_mutex);
 302         list_del_init(&rfkill->node);
 303         rfkill_toggle_radio(rfkill, RFKILL_STATE_OFF);
 304         mutex_unlock(&rfkill_mutex);
 305 }
 306
 307 /**
 308  * rfkill_allocate - allocate memory for rfkill structure.
 309  * @parent: device that has rf switch on it
 310  * @type: type of the switch (RFKILL_TYPE_*)
 311  *
 312  * This function should be called by the network driver when it needs
 313  * rfkill structure. Once the structure is allocated the driver shoud
 314  * finish its initialization by setting name, private data, enable_radio
 315  * and disable_radio methods and then register it with rfkill_register().
 316  * NOTE: If registration fails the structure shoudl be freed by calling
 317  * rfkill_free() otherwise rfkill_unregister() should be used.
 318  */
 319 struct rfkill *rfkill_allocate(struct device *parent, enum rfkill_type type)
 320 {
 321         struct rfkill *rfkill;
 322         struct device *dev;
 323
 324         rfkill = kzalloc(sizeof(struct rfkill), GFP_KERNEL);
 325         if (!rfkill)
 326                 return NULL;
 327
 328         mutex_init(&rfkill->mutex);
 329         INIT_LIST_HEAD(&rfkill->node);
 330         rfkill->type = type;
 331
 332         dev = &rfkill->dev;
 333         dev->class = &rfkill_class;
 334         dev->parent = parent;
 335         device_initialize(dev);
 336
 337         __module_get(THIS_MODULE);
 338
 339         return rfkill;
 340 }
 341 EXPORT_SYMBOL(rfkill_allocate);
 342
 343 /**
 344  * rfkill_free - Mark rfkill structure for deletion
 345  * @rfkill: rfkill structure to be destroyed
 346  *
 347  * Decrements reference count of rfkill structure so it is destroyed.
 348  * Note that rfkill_free() should _not_ be called after rfkill_unregister().
 349  */
 350 void rfkill_free(struct rfkill *rfkill)
 351 {
 352         if (rfkill)
 353                 put_device(&rfkill->dev);
 354 }
 355 EXPORT_SYMBOL(rfkill_free);
 356
 357 static void rfkill_led_trigger_register(struct rfkill *rfkill)
 358 {
 359 #ifdef CONFIG_RFKILL_LEDS
 360         int error;
 361
 362         rfkill->led_trigger.name = rfkill->dev.bus_id;
 363         error = led_trigger_register(&rfkill->led_trigger);
 364         if (error)
 365                 rfkill->led_trigger.name = NULL;
 366 #endif /* CONFIG_RFKILL_LEDS */
 367 }
 368
 369 static void rfkill_led_trigger_unregister(struct rfkill *rfkill)
 370 {
 371 #ifdef CONFIG_RFKILL_LEDS
 372         if (rfkill->led_trigger.name)
 373                 led_trigger_unregister(&rfkill->led_trigger);
 374 #endif
 375 }
 376
 377 /**
 378  * rfkill_register - Register a rfkill structure.
 379  * @rfkill: rfkill structure to be registered
 380  *
 381  * This function should be called by the network driver when the rfkill
 382  * structure needs to be registered. Immediately from registration the
 383  * switch driver should be able to service calls to toggle_radio.
 384  */
 385 int rfkill_register(struct rfkill *rfkill)
 386 {
 387         static atomic_t rfkill_no = ATOMIC_INIT(0);
 388         struct device *dev = &rfkill->dev;
 389         int error;
 390
 391         if (!rfkill->toggle_radio)
 392                 return -EINVAL;
 393         if (rfkill->type >= RFKILL_TYPE_MAX)
 394                 return -EINVAL;
 395
 396         snprintf(dev->bus_id, sizeof(dev->bus_id),
 397                  "rfkill%ld", (long)atomic_inc_return(&rfkill_no) - 1);
 398
 399         rfkill_led_trigger_register(rfkill);
 400
 401         error = rfkill_add_switch(rfkill);
 402         if (error) {
 403                 rfkill_led_trigger_unregister(rfkill);
 404                 return error;
 405         }
 406
 407         error = device_add(dev);
 408         if (error) {
 409                 rfkill_led_trigger_unregister(rfkill);
 410                 rfkill_remove_switch(rfkill);
 411                 return error;
 412         }
 413
 414         return 0;
 415 }
 416 EXPORT_SYMBOL(rfkill_register);
 417
 418 /**
 419  * rfkill_unregister - Uegister a rfkill structure.
 420  * @rfkill: rfkill structure to be unregistered
 421  *
 422  * This function should be called by the network driver during device
 423  * teardown to destroy rfkill structure. Note that rfkill_free() should
 424  * _not_ be called after rfkill_unregister().
 425  */
 426 void rfkill_unregister(struct rfkill *rfkill)
 427 {
 428         device_del(&rfkill->dev);
 429         rfkill_remove_switch(rfkill);
 430         rfkill_led_trigger_unregister(rfkill);
 431         put_device(&rfkill->dev);
 432 }
 433 EXPORT_SYMBOL(rfkill_unregister);
 434
 435 /*
 436  * Rfkill module initialization/deinitialization.
 437  */
 438 static int __init rfkill_init(void)
 439 {
 440         int error;
 441         int i;
 442
 443         for (i = 0; i < ARRAY_SIZE(rfkill_states); i++)
 444                 rfkill_states[i] = RFKILL_STATE_ON;
 445
 446         error = class_register(&rfkill_class);
 447         if (error) {
 448                 printk(KERN_ERR "rfkill: unable to register rfkill class\n");
 449                 return error;
 450         }
 451
 452         return 0;
 453 }
 454
 455 static void __exit rfkill_exit(void)
 456 {
 457         class_unregister(&rfkill_class);
 458 }
 459
 460 subsys_initcall(rfkill_init);
 461 module_exit(rfkill_exit);