/*
   * Copyright (C) 2006 - 2007 Ivo van Doorn
   * Copyright (C) 2007 Dmitry Torokhov
   * Copyright 2009 Johannes Berg <johannes@sipsolutions.net>
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License as published by
   * the Free Software Foundation; either version 2 of the License, or
   * (at your option) any later version.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License

   * along with this program; if not, see <http://www.gnu.org/licenses/>.

   */
  
  #include <linux/kernel.h>
  #include <linux/module.h>
  #include <linux/init.h>
  #include <linux/workqueue.h>
  #include <linux/capability.h>
  #include <linux/list.h>
  #include <linux/mutex.h>
  #include <linux/rfkill.h>

  #include <linux/sched.h>

  #include <linux/spinlock.h>

  #include <linux/device.h>

  #include <linux/miscdevice.h>
  #include <linux/wait.h>
  #include <linux/poll.h>
  #include <linux/fs.h>

  #include <linux/slab.h>

  
  #include "rfkill.h"
  
  #define POLL_INTERVAL		(5 * HZ)
  
  #define RFKILL_BLOCK_HW		BIT(0)
  #define RFKILL_BLOCK_SW		BIT(1)
  #define RFKILL_BLOCK_SW_PREV	BIT(2)
  #define RFKILL_BLOCK_ANY	(RFKILL_BLOCK_HW |\
  				 RFKILL_BLOCK_SW |\
  				 RFKILL_BLOCK_SW_PREV)
  #define RFKILL_BLOCK_SW_SETCALL	BIT(31)
  
  struct rfkill {
  	spinlock_t		lock;

  	enum rfkill_type	type;
  
  	unsigned long		state;

  	u32			idx;

  	bool			registered;

  	bool			persistent;

  	bool			polling_paused;
  	bool			suspended;

  
  	const struct rfkill_ops	*ops;
  	void			*data;
  
  #ifdef CONFIG_RFKILL_LEDS
  	struct led_trigger	led_trigger;
  	const char		*ledtrigname;
  #endif
  
  	struct device		dev;
  	struct list_head	node;
  
  	struct delayed_work	poll_work;
  	struct work_struct	uevent_work;
  	struct work_struct	sync_work;

  	char			name[];

  };
  #define to_rfkill(d)	container_of(d, struct rfkill, dev)

  struct rfkill_int_event {
  	struct list_head	list;
  	struct rfkill_event	ev;
  };
  
  struct rfkill_data {
  	struct list_head	list;
  	struct list_head	events;
  	struct mutex		mtx;
  	wait_queue_head_t	read_wait;
  	bool			input_handler;
  };

  
  
  MODULE_AUTHOR("Ivo van Doorn <IvDoorn@gmail.com>");
  MODULE_AUTHOR("Johannes Berg <johannes@sipsolutions.net>");
  MODULE_DESCRIPTION("RF switch support");
  MODULE_LICENSE("GPL");
  
  
  /*
   * The locking here should be made much smarter, we currently have
   * a bit of a stupid situation because drivers might want to register
   * the rfkill struct under their own lock, and take this lock during
   * rfkill method calls -- which will cause an AB-BA deadlock situation.
   *
   * To fix that, we need to rework this code here to be mostly lock-free
   * and only use the mutex for list manipulations, not to protect the
   * various other global variables. Then we can avoid holding the mutex
   * around driver operations, and all is happy.
   */
  static LIST_HEAD(rfkill_list);	/* list of registered rf switches */
  static DEFINE_MUTEX(rfkill_global_mutex);

  static LIST_HEAD(rfkill_fds);	/* list of open fds of /dev/rfkill */

  
  static unsigned int rfkill_default_state = 1;
  module_param_named(default_state, rfkill_default_state, uint, 0444);
  MODULE_PARM_DESC(default_state,
  		 "Default initial state for all radio types, 0 = radio off");
  
  static struct {

  	bool cur, sav;

  } rfkill_global_states[NUM_RFKILL_TYPES];

  static bool rfkill_epo_lock_active;
  
  
  #ifdef CONFIG_RFKILL_LEDS
  static void rfkill_led_trigger_event(struct rfkill *rfkill)
  {
  	struct led_trigger *trigger;
  
  	if (!rfkill->registered)
  		return;
  
  	trigger = &rfkill->led_trigger;
  
  	if (rfkill->state & RFKILL_BLOCK_ANY)
  		led_trigger_event(trigger, LED_OFF);
  	else
  		led_trigger_event(trigger, LED_FULL);
  }
  
  static void rfkill_led_trigger_activate(struct led_classdev *led)
  {
  	struct rfkill *rfkill;
  
  	rfkill = container_of(led->trigger, struct rfkill, led_trigger);
  
  	rfkill_led_trigger_event(rfkill);
  }

  const char *rfkill_get_led_trigger_name(struct rfkill *rfkill)
  {
  	return rfkill->led_trigger.name;
  }
  EXPORT_SYMBOL(rfkill_get_led_trigger_name);
  
  void rfkill_set_led_trigger_name(struct rfkill *rfkill, const char *name)
  {
  	BUG_ON(!rfkill);
  
  	rfkill->ledtrigname = name;
  }
  EXPORT_SYMBOL(rfkill_set_led_trigger_name);

  static int rfkill_led_trigger_register(struct rfkill *rfkill)
  {
  	rfkill->led_trigger.name = rfkill->ledtrigname
  					? : dev_name(&rfkill->dev);
  	rfkill->led_trigger.activate = rfkill_led_trigger_activate;
  	return led_trigger_register(&rfkill->led_trigger);
  }
  
  static void rfkill_led_trigger_unregister(struct rfkill *rfkill)
  {
  	led_trigger_unregister(&rfkill->led_trigger);
  }

  
  static struct led_trigger rfkill_any_led_trigger;
  static struct work_struct rfkill_any_work;
  
  static void rfkill_any_led_trigger_worker(struct work_struct *work)
  {
  	enum led_brightness brightness = LED_OFF;
  	struct rfkill *rfkill;
  
  	mutex_lock(&rfkill_global_mutex);
  	list_for_each_entry(rfkill, &rfkill_list, node) {
  		if (!(rfkill->state & RFKILL_BLOCK_ANY)) {
  			brightness = LED_FULL;
  			break;
  		}
  	}
  	mutex_unlock(&rfkill_global_mutex);
  
  	led_trigger_event(&rfkill_any_led_trigger, brightness);
  }
  
  static void rfkill_any_led_trigger_event(void)
  {
  	schedule_work(&rfkill_any_work);
  }
  
  static void rfkill_any_led_trigger_activate(struct led_classdev *led_cdev)
  {
  	rfkill_any_led_trigger_event();
  }
  
  static int rfkill_any_led_trigger_register(void)
  {
  	INIT_WORK(&rfkill_any_work, rfkill_any_led_trigger_worker);
  	rfkill_any_led_trigger.name = "rfkill-any";
  	rfkill_any_led_trigger.activate = rfkill_any_led_trigger_activate;
  	return led_trigger_register(&rfkill_any_led_trigger);
  }
  
  static void rfkill_any_led_trigger_unregister(void)
  {
  	led_trigger_unregister(&rfkill_any_led_trigger);
  	cancel_work_sync(&rfkill_any_work);
  }

  #else
  static void rfkill_led_trigger_event(struct rfkill *rfkill)
  {
  }
  
  static inline int rfkill_led_trigger_register(struct rfkill *rfkill)
  {
  	return 0;
  }
  
  static inline void rfkill_led_trigger_unregister(struct rfkill *rfkill)
  {
  }

  
  static void rfkill_any_led_trigger_event(void)
  {
  }
  
  static int rfkill_any_led_trigger_register(void)
  {
  	return 0;
  }
  
  static void rfkill_any_led_trigger_unregister(void)
  {
  }

  #endif /* CONFIG_RFKILL_LEDS */

  static void rfkill_fill_event(struct rfkill_event *ev, struct rfkill *rfkill,
  			      enum rfkill_operation op)
  {
  	unsigned long flags;
  
  	ev->idx = rfkill->idx;
  	ev->type = rfkill->type;
  	ev->op = op;
  
  	spin_lock_irqsave(&rfkill->lock, flags);
  	ev->hard = !!(rfkill->state & RFKILL_BLOCK_HW);
  	ev->soft = !!(rfkill->state & (RFKILL_BLOCK_SW |
  					RFKILL_BLOCK_SW_PREV));
  	spin_unlock_irqrestore(&rfkill->lock, flags);
  }
  
  static void rfkill_send_events(struct rfkill *rfkill, enum rfkill_operation op)
  {
  	struct rfkill_data *data;
  	struct rfkill_int_event *ev;
  
  	list_for_each_entry(data, &rfkill_fds, list) {
  		ev = kzalloc(sizeof(*ev), GFP_KERNEL);
  		if (!ev)
  			continue;
  		rfkill_fill_event(&ev->ev, rfkill, op);
  		mutex_lock(&data->mtx);
  		list_add_tail(&ev->list, &data->events);
  		mutex_unlock(&data->mtx);
  		wake_up_interruptible(&data->read_wait);
  	}
  }
  
  static void rfkill_event(struct rfkill *rfkill)

  {

  	if (!rfkill->registered)

  		return;
  
  	kobject_uevent(&rfkill->dev.kobj, KOBJ_CHANGE);

  
  	/* also send event to /dev/rfkill */
  	rfkill_send_events(rfkill, RFKILL_OP_CHANGE);

  }

  /**
   * rfkill_set_block - wrapper for set_block method
   *
   * @rfkill: the rfkill struct to use
   * @blocked: the new software state
   *
   * Calls the set_block method (when applicable) and handles notifications
   * etc. as well.
   */
  static void rfkill_set_block(struct rfkill *rfkill, bool blocked)
  {
  	unsigned long flags;

  	bool prev, curr;

  	int err;

  	if (unlikely(rfkill->dev.power.power_state.event & PM_EVENT_SLEEP))
  		return;

  	/*
  	 * Some platforms (...!) generate input events which affect the
  	 * _hard_ kill state -- whenever something tries to change the
  	 * current software state query the hardware state too.
  	 */
  	if (rfkill->ops->query)
  		rfkill->ops->query(rfkill, rfkill->data);
  
  	spin_lock_irqsave(&rfkill->lock, flags);

  	prev = rfkill->state & RFKILL_BLOCK_SW;

  	if (prev)

  		rfkill->state |= RFKILL_BLOCK_SW_PREV;
  	else
  		rfkill->state &= ~RFKILL_BLOCK_SW_PREV;
  
  	if (blocked)
  		rfkill->state |= RFKILL_BLOCK_SW;
  	else
  		rfkill->state &= ~RFKILL_BLOCK_SW;
  
  	rfkill->state |= RFKILL_BLOCK_SW_SETCALL;
  	spin_unlock_irqrestore(&rfkill->lock, flags);

  	err = rfkill->ops->set_block(rfkill->data, blocked);
  
  	spin_lock_irqsave(&rfkill->lock, flags);
  	if (err) {
  		/*

  		 * Failed -- reset status to _PREV, which may be different
  		 * from what we have set _PREV to earlier in this function

  		 * if rfkill_set_sw_state was invoked.
  		 */
  		if (rfkill->state & RFKILL_BLOCK_SW_PREV)
  			rfkill->state |= RFKILL_BLOCK_SW;
  		else
  			rfkill->state &= ~RFKILL_BLOCK_SW;
  	}
  	rfkill->state &= ~RFKILL_BLOCK_SW_SETCALL;
  	rfkill->state &= ~RFKILL_BLOCK_SW_PREV;

  	curr = rfkill->state & RFKILL_BLOCK_SW;

  	spin_unlock_irqrestore(&rfkill->lock, flags);
  
  	rfkill_led_trigger_event(rfkill);

  	rfkill_any_led_trigger_event();

  
  	if (prev != curr)
  		rfkill_event(rfkill);

  }

  static void rfkill_update_global_state(enum rfkill_type type, bool blocked)
  {
  	int i;
  
  	if (type != RFKILL_TYPE_ALL) {
  		rfkill_global_states[type].cur = blocked;
  		return;
  	}
  
  	for (i = 0; i < NUM_RFKILL_TYPES; i++)
  		rfkill_global_states[i].cur = blocked;
  }

  #ifdef CONFIG_RFKILL_INPUT
  static atomic_t rfkill_input_disabled = ATOMIC_INIT(0);

  /**
   * __rfkill_switch_all - Toggle state of all switches of given type
   * @type: type of interfaces to be affected

   * @blocked: the new state

   *
   * This function sets the state of all switches of given type,

   * unless a specific switch is suspended.

   *
   * Caller must have acquired rfkill_global_mutex.
   */
  static void __rfkill_switch_all(const enum rfkill_type type, bool blocked)
  {
  	struct rfkill *rfkill;

  	rfkill_update_global_state(type, blocked);

  	list_for_each_entry(rfkill, &rfkill_list, node) {

  		if (rfkill->type != type && type != RFKILL_TYPE_ALL)

  			continue;
  
  		rfkill_set_block(rfkill, blocked);
  	}
  }
  
  /**
   * rfkill_switch_all - Toggle state of all switches of given type
   * @type: type of interfaces to be affected

   * @blocked: the new state

   *
   * Acquires rfkill_global_mutex and calls __rfkill_switch_all(@type, @state).
   * Please refer to __rfkill_switch_all() for details.
   *
   * Does nothing if the EPO lock is active.
   */
  void rfkill_switch_all(enum rfkill_type type, bool blocked)
  {

  	if (atomic_read(&rfkill_input_disabled))
  		return;

  	mutex_lock(&rfkill_global_mutex);
  
  	if (!rfkill_epo_lock_active)
  		__rfkill_switch_all(type, blocked);
  
  	mutex_unlock(&rfkill_global_mutex);
  }
  
  /**
   * rfkill_epo - emergency power off all transmitters
   *
   * This kicks all non-suspended rfkill devices to RFKILL_STATE_SOFT_BLOCKED,
   * ignoring everything in its path but rfkill_global_mutex and rfkill->mutex.
   *
   * The global state before the EPO is saved and can be restored later
   * using rfkill_restore_states().
   */
  void rfkill_epo(void)
  {
  	struct rfkill *rfkill;
  	int i;

  	if (atomic_read(&rfkill_input_disabled))
  		return;

  	mutex_lock(&rfkill_global_mutex);
  
  	rfkill_epo_lock_active = true;
  	list_for_each_entry(rfkill, &rfkill_list, node)
  		rfkill_set_block(rfkill, true);
  
  	for (i = 0; i < NUM_RFKILL_TYPES; i++) {

  		rfkill_global_states[i].sav = rfkill_global_states[i].cur;

  		rfkill_global_states[i].cur = true;
  	}

  	mutex_unlock(&rfkill_global_mutex);
  }
  
  /**
   * rfkill_restore_states - restore global states
   *
   * Restore (and sync switches to) the global state from the
   * states in rfkill_default_states.  This can undo the effects of
   * a call to rfkill_epo().
   */
  void rfkill_restore_states(void)
  {
  	int i;

  	if (atomic_read(&rfkill_input_disabled))
  		return;

  	mutex_lock(&rfkill_global_mutex);
  
  	rfkill_epo_lock_active = false;
  	for (i = 0; i < NUM_RFKILL_TYPES; i++)

  		__rfkill_switch_all(i, rfkill_global_states[i].sav);

  	mutex_unlock(&rfkill_global_mutex);
  }
  
  /**
   * rfkill_remove_epo_lock - unlock state changes
   *
   * Used by rfkill-input manually unlock state changes, when
   * the EPO switch is deactivated.
   */
  void rfkill_remove_epo_lock(void)
  {

  	if (atomic_read(&rfkill_input_disabled))
  		return;

  	mutex_lock(&rfkill_global_mutex);
  	rfkill_epo_lock_active = false;
  	mutex_unlock(&rfkill_global_mutex);
  }
  
  /**
   * rfkill_is_epo_lock_active - returns true EPO is active
   *
   * Returns 0 (false) if there is NOT an active EPO contidion,
   * and 1 (true) if there is an active EPO contition, which
   * locks all radios in one of the BLOCKED states.
   *
   * Can be called in atomic context.
   */
  bool rfkill_is_epo_lock_active(void)
  {
  	return rfkill_epo_lock_active;
  }
  
  /**
   * rfkill_get_global_sw_state - returns global state for a type
   * @type: the type to get the global state of
   *
   * Returns the current global state for a given wireless
   * device type.
   */
  bool rfkill_get_global_sw_state(const enum rfkill_type type)
  {
  	return rfkill_global_states[type].cur;
  }

  #endif

  bool rfkill_set_hw_state(struct rfkill *rfkill, bool blocked)
  {

  	unsigned long flags;
  	bool ret, prev;
  
  	BUG_ON(!rfkill);

  	spin_lock_irqsave(&rfkill->lock, flags);
  	prev = !!(rfkill->state & RFKILL_BLOCK_HW);
  	if (blocked)
  		rfkill->state |= RFKILL_BLOCK_HW;
  	else
  		rfkill->state &= ~RFKILL_BLOCK_HW;
  	ret = !!(rfkill->state & RFKILL_BLOCK_ANY);
  	spin_unlock_irqrestore(&rfkill->lock, flags);

  	rfkill_led_trigger_event(rfkill);

  	rfkill_any_led_trigger_event();

  	if (rfkill->registered && prev != blocked)

  		schedule_work(&rfkill->uevent_work);
  
  	return ret;
  }
  EXPORT_SYMBOL(rfkill_set_hw_state);
  
  static void __rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
  {
  	u32 bit = RFKILL_BLOCK_SW;
  
  	/* if in a ops->set_block right now, use other bit */
  	if (rfkill->state & RFKILL_BLOCK_SW_SETCALL)
  		bit = RFKILL_BLOCK_SW_PREV;
  
  	if (blocked)
  		rfkill->state |= bit;
  	else
  		rfkill->state &= ~bit;
  }
  
  bool rfkill_set_sw_state(struct rfkill *rfkill, bool blocked)
  {
  	unsigned long flags;
  	bool prev, hwblock;
  
  	BUG_ON(!rfkill);
  
  	spin_lock_irqsave(&rfkill->lock, flags);
  	prev = !!(rfkill->state & RFKILL_BLOCK_SW);
  	__rfkill_set_sw_state(rfkill, blocked);
  	hwblock = !!(rfkill->state & RFKILL_BLOCK_HW);
  	blocked = blocked || hwblock;
  	spin_unlock_irqrestore(&rfkill->lock, flags);

  	if (!rfkill->registered)
  		return blocked;

  	if (prev != blocked && !hwblock)
  		schedule_work(&rfkill->uevent_work);
  
  	rfkill_led_trigger_event(rfkill);

  	rfkill_any_led_trigger_event();

  
  	return blocked;
  }
  EXPORT_SYMBOL(rfkill_set_sw_state);

  void rfkill_init_sw_state(struct rfkill *rfkill, bool blocked)
  {
  	unsigned long flags;
  
  	BUG_ON(!rfkill);
  	BUG_ON(rfkill->registered);
  
  	spin_lock_irqsave(&rfkill->lock, flags);
  	__rfkill_set_sw_state(rfkill, blocked);
  	rfkill->persistent = true;
  	spin_unlock_irqrestore(&rfkill->lock, flags);
  }
  EXPORT_SYMBOL(rfkill_init_sw_state);

  void rfkill_set_states(struct rfkill *rfkill, bool sw, bool hw)
  {
  	unsigned long flags;
  	bool swprev, hwprev;
  
  	BUG_ON(!rfkill);
  
  	spin_lock_irqsave(&rfkill->lock, flags);
  
  	/*
  	 * No need to care about prev/setblock ... this is for uevent only
  	 * and that will get triggered by rfkill_set_block anyway.
  	 */
  	swprev = !!(rfkill->state & RFKILL_BLOCK_SW);
  	hwprev = !!(rfkill->state & RFKILL_BLOCK_HW);
  	__rfkill_set_sw_state(rfkill, sw);

  	if (hw)
  		rfkill->state |= RFKILL_BLOCK_HW;
  	else
  		rfkill->state &= ~RFKILL_BLOCK_HW;

  
  	spin_unlock_irqrestore(&rfkill->lock, flags);

  	if (!rfkill->registered) {
  		rfkill->persistent = true;
  	} else {
  		if (swprev != sw || hwprev != hw)
  			schedule_work(&rfkill->uevent_work);

  		rfkill_led_trigger_event(rfkill);

  		rfkill_any_led_trigger_event();

  	}

  }
  EXPORT_SYMBOL(rfkill_set_states);

  static const char * const rfkill_types[] = {
  	NULL, /* RFKILL_TYPE_ALL */
  	"wlan",
  	"bluetooth",
  	"ultrawideband",
  	"wimax",
  	"wwan",
  	"gps",
  	"fm",
  	"nfc",
  };
  
  enum rfkill_type rfkill_find_type(const char *name)
  {
  	int i;
  
  	BUILD_BUG_ON(ARRAY_SIZE(rfkill_types) != NUM_RFKILL_TYPES);
  
  	if (!name)
  		return RFKILL_TYPE_ALL;
  
  	for (i = 1; i < NUM_RFKILL_TYPES; i++)
  		if (!strcmp(name, rfkill_types[i]))
  			return i;
  	return RFKILL_TYPE_ALL;
  }
  EXPORT_SYMBOL(rfkill_find_type);

  static ssize_t name_show(struct device *dev, struct device_attribute *attr,
  			 char *buf)

  {
  	struct rfkill *rfkill = to_rfkill(dev);
  
  	return sprintf(buf, "%s
  ", rfkill->name);
  }

  static DEVICE_ATTR_RO(name);

  static ssize_t type_show(struct device *dev, struct device_attribute *attr,
  			 char *buf)

  {
  	struct rfkill *rfkill = to_rfkill(dev);

  	return sprintf(buf, "%s
  ", rfkill_types[rfkill->type]);

  }

  static DEVICE_ATTR_RO(type);

  static ssize_t index_show(struct device *dev, struct device_attribute *attr,
  			  char *buf)

  {
  	struct rfkill *rfkill = to_rfkill(dev);
  
  	return sprintf(buf, "%d
  ", rfkill->idx);
  }

  static DEVICE_ATTR_RO(index);

  static ssize_t persistent_show(struct device *dev,
  			       struct device_attribute *attr, char *buf)

  {
  	struct rfkill *rfkill = to_rfkill(dev);
  
  	return sprintf(buf, "%d
  ", rfkill->persistent);
  }

  static DEVICE_ATTR_RO(persistent);

  static ssize_t hard_show(struct device *dev, struct device_attribute *attr,
  			 char *buf)

  {
  	struct rfkill *rfkill = to_rfkill(dev);

  	return sprintf(buf, "%d
  ", (rfkill->state & RFKILL_BLOCK_HW) ? 1 : 0 );

  }

  static DEVICE_ATTR_RO(hard);

  static ssize_t soft_show(struct device *dev, struct device_attribute *attr,
  			 char *buf)

  {
  	struct rfkill *rfkill = to_rfkill(dev);

  	return sprintf(buf, "%d
  ", (rfkill->state & RFKILL_BLOCK_SW) ? 1 : 0 );

  }

  static ssize_t soft_store(struct device *dev, struct device_attribute *attr,
  			  const char *buf, size_t count)

  {
  	struct rfkill *rfkill = to_rfkill(dev);
  	unsigned long state;
  	int err;
  
  	if (!capable(CAP_NET_ADMIN))
  		return -EPERM;

  	err = kstrtoul(buf, 0, &state);

  	if (err)
  		return err;
  
  	if (state > 1 )
  		return -EINVAL;
  
  	mutex_lock(&rfkill_global_mutex);
  	rfkill_set_block(rfkill, state);
  	mutex_unlock(&rfkill_global_mutex);

  	return count;

  }

  static DEVICE_ATTR_RW(soft);

  static u8 user_state_from_blocked(unsigned long state)
  {
  	if (state & RFKILL_BLOCK_HW)
  		return RFKILL_USER_STATE_HARD_BLOCKED;
  	if (state & RFKILL_BLOCK_SW)
  		return RFKILL_USER_STATE_SOFT_BLOCKED;
  
  	return RFKILL_USER_STATE_UNBLOCKED;
  }

  static ssize_t state_show(struct device *dev, struct device_attribute *attr,
  			  char *buf)

  {
  	struct rfkill *rfkill = to_rfkill(dev);

  	return sprintf(buf, "%d
  ", user_state_from_blocked(rfkill->state));

  }

  static ssize_t state_store(struct device *dev, struct device_attribute *attr,
  			   const char *buf, size_t count)

  {

  	struct rfkill *rfkill = to_rfkill(dev);
  	unsigned long state;
  	int err;
  
  	if (!capable(CAP_NET_ADMIN))
  		return -EPERM;

  	err = kstrtoul(buf, 0, &state);

  	if (err)
  		return err;
  
  	if (state != RFKILL_USER_STATE_SOFT_BLOCKED &&
  	    state != RFKILL_USER_STATE_UNBLOCKED)
  		return -EINVAL;
  
  	mutex_lock(&rfkill_global_mutex);
  	rfkill_set_block(rfkill, state == RFKILL_USER_STATE_SOFT_BLOCKED);
  	mutex_unlock(&rfkill_global_mutex);

  	return count;

  }

  static DEVICE_ATTR_RW(state);

  static struct attribute *rfkill_dev_attrs[] = {
  	&dev_attr_name.attr,
  	&dev_attr_type.attr,
  	&dev_attr_index.attr,
  	&dev_attr_persistent.attr,
  	&dev_attr_state.attr,

  	&dev_attr_soft.attr,
  	&dev_attr_hard.attr,
  	NULL,

  };

  ATTRIBUTE_GROUPS(rfkill_dev);

  
  static void rfkill_release(struct device *dev)
  {
  	struct rfkill *rfkill = to_rfkill(dev);
  
  	kfree(rfkill);
  }
  
  static int rfkill_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
  {
  	struct rfkill *rfkill = to_rfkill(dev);
  	unsigned long flags;
  	u32 state;
  	int error;
  
  	error = add_uevent_var(env, "RFKILL_NAME=%s", rfkill->name);
  	if (error)
  		return error;
  	error = add_uevent_var(env, "RFKILL_TYPE=%s",

  			       rfkill_types[rfkill->type]);

  	if (error)
  		return error;
  	spin_lock_irqsave(&rfkill->lock, flags);
  	state = rfkill->state;
  	spin_unlock_irqrestore(&rfkill->lock, flags);
  	error = add_uevent_var(env, "RFKILL_STATE=%d",
  			       user_state_from_blocked(state));
  	return error;
  }
  
  void rfkill_pause_polling(struct rfkill *rfkill)
  {
  	BUG_ON(!rfkill);
  
  	if (!rfkill->ops->poll)
  		return;

  	rfkill->polling_paused = true;

  	cancel_delayed_work_sync(&rfkill->poll_work);
  }
  EXPORT_SYMBOL(rfkill_pause_polling);
  
  void rfkill_resume_polling(struct rfkill *rfkill)
  {
  	BUG_ON(!rfkill);
  
  	if (!rfkill->ops->poll)
  		return;

  	rfkill->polling_paused = false;
  
  	if (rfkill->suspended)
  		return;

  	queue_delayed_work(system_power_efficient_wq,
  			   &rfkill->poll_work, 0);

  }
  EXPORT_SYMBOL(rfkill_resume_polling);

  #ifdef CONFIG_PM_SLEEP
  static int rfkill_suspend(struct device *dev)

  {
  	struct rfkill *rfkill = to_rfkill(dev);

  	rfkill->suspended = true;
  	cancel_delayed_work_sync(&rfkill->poll_work);

  	return 0;
  }
  
  static int rfkill_resume(struct device *dev)
  {
  	struct rfkill *rfkill = to_rfkill(dev);
  	bool cur;

  	rfkill->suspended = false;

  	if (!rfkill->persistent) {
  		cur = !!(rfkill->state & RFKILL_BLOCK_SW);
  		rfkill_set_block(rfkill, cur);
  	}

  	if (rfkill->ops->poll && !rfkill->polling_paused)
  		queue_delayed_work(system_power_efficient_wq,
  				   &rfkill->poll_work, 0);

  
  	return 0;
  }

  static SIMPLE_DEV_PM_OPS(rfkill_pm_ops, rfkill_suspend, rfkill_resume);
  #define RFKILL_PM_OPS (&rfkill_pm_ops)
  #else
  #define RFKILL_PM_OPS NULL
  #endif

  static struct class rfkill_class = {
  	.name		= "rfkill",
  	.dev_release	= rfkill_release,

  	.dev_groups	= rfkill_dev_groups,

  	.dev_uevent	= rfkill_dev_uevent,

  	.pm		= RFKILL_PM_OPS,

  };

  bool rfkill_blocked(struct rfkill *rfkill)
  {
  	unsigned long flags;
  	u32 state;
  
  	spin_lock_irqsave(&rfkill->lock, flags);
  	state = rfkill->state;
  	spin_unlock_irqrestore(&rfkill->lock, flags);
  
  	return !!(state & RFKILL_BLOCK_ANY);
  }
  EXPORT_SYMBOL(rfkill_blocked);

  
  struct rfkill * __must_check rfkill_alloc(const char *name,
  					  struct device *parent,
  					  const enum rfkill_type type,
  					  const struct rfkill_ops *ops,
  					  void *ops_data)
  {
  	struct rfkill *rfkill;
  	struct device *dev;
  
  	if (WARN_ON(!ops))
  		return NULL;
  
  	if (WARN_ON(!ops->set_block))
  		return NULL;
  
  	if (WARN_ON(!name))
  		return NULL;

  	if (WARN_ON(type == RFKILL_TYPE_ALL || type >= NUM_RFKILL_TYPES))

  		return NULL;

  	rfkill = kzalloc(sizeof(*rfkill) + strlen(name) + 1, GFP_KERNEL);

  	if (!rfkill)
  		return NULL;
  
  	spin_lock_init(&rfkill->lock);
  	INIT_LIST_HEAD(&rfkill->node);
  	rfkill->type = type;

  	strcpy(rfkill->name, name);

  	rfkill->ops = ops;
  	rfkill->data = ops_data;
  
  	dev = &rfkill->dev;
  	dev->class = &rfkill_class;
  	dev->parent = parent;
  	device_initialize(dev);
  
  	return rfkill;
  }
  EXPORT_SYMBOL(rfkill_alloc);
  
  static void rfkill_poll(struct work_struct *work)
  {
  	struct rfkill *rfkill;
  
  	rfkill = container_of(work, struct rfkill, poll_work.work);
  
  	/*
  	 * Poll hardware state -- driver will use one of the
  	 * rfkill_set{,_hw,_sw}_state functions and use its
  	 * return value to update the current status.
  	 */
  	rfkill->ops->poll(rfkill, rfkill->data);

  	queue_delayed_work(system_power_efficient_wq,
  		&rfkill->poll_work,

  		round_jiffies_relative(POLL_INTERVAL));
  }
  
  static void rfkill_uevent_work(struct work_struct *work)
  {
  	struct rfkill *rfkill;
  
  	rfkill = container_of(work, struct rfkill, uevent_work);

  	mutex_lock(&rfkill_global_mutex);
  	rfkill_event(rfkill);
  	mutex_unlock(&rfkill_global_mutex);

  }
  
  static void rfkill_sync_work(struct work_struct *work)
  {
  	struct rfkill *rfkill;
  	bool cur;
  
  	rfkill = container_of(work, struct rfkill, sync_work);
  
  	mutex_lock(&rfkill_global_mutex);
  	cur = rfkill_global_states[rfkill->type].cur;
  	rfkill_set_block(rfkill, cur);
  	mutex_unlock(&rfkill_global_mutex);
  }
  
  int __must_check rfkill_register(struct rfkill *rfkill)
  {
  	static unsigned long rfkill_no;
  	struct device *dev = &rfkill->dev;
  	int error;
  
  	BUG_ON(!rfkill);
  
  	mutex_lock(&rfkill_global_mutex);
  
  	if (rfkill->registered) {
  		error = -EALREADY;
  		goto unlock;
  	}

  	rfkill->idx = rfkill_no;

  	dev_set_name(dev, "rfkill%lu", rfkill_no);
  	rfkill_no++;

  	list_add_tail(&rfkill->node, &rfkill_list);
  
  	error = device_add(dev);
  	if (error)
  		goto remove;
  
  	error = rfkill_led_trigger_register(rfkill);
  	if (error)
  		goto devdel;
  
  	rfkill->registered = true;

  	INIT_DELAYED_WORK(&rfkill->poll_work, rfkill_poll);

  	INIT_WORK(&rfkill->uevent_work, rfkill_uevent_work);

  	INIT_WORK(&rfkill->sync_work, rfkill_sync_work);

  
  	if (rfkill->ops->poll)

  		queue_delayed_work(system_power_efficient_wq,
  			&rfkill->poll_work,

  			round_jiffies_relative(POLL_INTERVAL));

  
  	if (!rfkill->persistent || rfkill_epo_lock_active) {
  		schedule_work(&rfkill->sync_work);
  	} else {
  #ifdef CONFIG_RFKILL_INPUT
  		bool soft_blocked = !!(rfkill->state & RFKILL_BLOCK_SW);
  
  		if (!atomic_read(&rfkill_input_disabled))
  			__rfkill_switch_all(rfkill->type, soft_blocked);
  #endif
  	}

  	rfkill_any_led_trigger_event();

  	rfkill_send_events(rfkill, RFKILL_OP_ADD);

  
  	mutex_unlock(&rfkill_global_mutex);
  	return 0;
  
   devdel:
  	device_del(&rfkill->dev);
   remove:
  	list_del_init(&rfkill->node);
   unlock:
  	mutex_unlock(&rfkill_global_mutex);
  	return error;
  }
  EXPORT_SYMBOL(rfkill_register);
  
  void rfkill_unregister(struct rfkill *rfkill)
  {
  	BUG_ON(!rfkill);
  
  	if (rfkill->ops->poll)
  		cancel_delayed_work_sync(&rfkill->poll_work);
  
  	cancel_work_sync(&rfkill->uevent_work);
  	cancel_work_sync(&rfkill->sync_work);
  
  	rfkill->registered = false;
  
  	device_del(&rfkill->dev);
  
  	mutex_lock(&rfkill_global_mutex);

  	rfkill_send_events(rfkill, RFKILL_OP_DEL);

  	list_del_init(&rfkill->node);

  	rfkill_any_led_trigger_event();

  	mutex_unlock(&rfkill_global_mutex);
  
  	rfkill_led_trigger_unregister(rfkill);
  }
  EXPORT_SYMBOL(rfkill_unregister);
  
  void rfkill_destroy(struct rfkill *rfkill)
  {
  	if (rfkill)
  		put_device(&rfkill->dev);
  }
  EXPORT_SYMBOL(rfkill_destroy);

  static int rfkill_fop_open(struct inode *inode, struct file *file)
  {
  	struct rfkill_data *data;
  	struct rfkill *rfkill;
  	struct rfkill_int_event *ev, *tmp;
  
  	data = kzalloc(sizeof(*data), GFP_KERNEL);
  	if (!data)
  		return -ENOMEM;
  
  	INIT_LIST_HEAD(&data->events);
  	mutex_init(&data->mtx);
  	init_waitqueue_head(&data->read_wait);
  
  	mutex_lock(&rfkill_global_mutex);
  	mutex_lock(&data->mtx);
  	/*
  	 * start getting events from elsewhere but hold mtx to get
  	 * startup events added first
  	 */

  
  	list_for_each_entry(rfkill, &rfkill_list, node) {
  		ev = kzalloc(sizeof(*ev), GFP_KERNEL);
  		if (!ev)
  			goto free;
  		rfkill_fill_event(&ev->ev, rfkill, RFKILL_OP_ADD);
  		list_add_tail(&ev->list, &data->events);
  	}

  	list_add(&data->list, &rfkill_fds);

  	mutex_unlock(&data->mtx);
  	mutex_unlock(&rfkill_global_mutex);
  
  	file->private_data = data;
  
  	return nonseekable_open(inode, file);
  
   free:
  	mutex_unlock(&data->mtx);
  	mutex_unlock(&rfkill_global_mutex);
  	mutex_destroy(&data->mtx);
  	list_for_each_entry_safe(ev, tmp, &data->events, list)
  		kfree(ev);
  	kfree(data);
  	return -ENOMEM;
  }
  
  static unsigned int rfkill_fop_poll(struct file *file, poll_table *wait)
  {
  	struct rfkill_data *data = file->private_data;
  	unsigned int res = POLLOUT | POLLWRNORM;
  
  	poll_wait(file, &data->read_wait, wait);
  
  	mutex_lock(&data->mtx);
  	if (!list_empty(&data->events))
  		res = POLLIN | POLLRDNORM;
  	mutex_unlock(&data->mtx);
  
  	return res;
  }

  static ssize_t rfkill_fop_read(struct file *file, char __user *buf,
  			       size_t count, loff_t *pos)
  {
  	struct rfkill_data *data = file->private_data;
  	struct rfkill_int_event *ev;
  	unsigned long sz;
  	int ret;
  
  	mutex_lock(&data->mtx);
  
  	while (list_empty(&data->events)) {
  		if (file->f_flags & O_NONBLOCK) {
  			ret = -EAGAIN;
  			goto out;
  		}
  		mutex_unlock(&data->mtx);

  		/* since we re-check and it just compares pointers,
  		 * using !list_empty() without locking isn't a problem
  		 */

  		ret = wait_event_interruptible(data->read_wait,

  					       !list_empty(&data->events));

  		mutex_lock(&data->mtx);
  
  		if (ret)
  			goto out;
  	}
  
  	ev = list_first_entry(&data->events, struct rfkill_int_event,
  				list);
  
  	sz = min_t(unsigned long, sizeof(ev->ev), count);
  	ret = sz;
  	if (copy_to_user(buf, &ev->ev, sz))
  		ret = -EFAULT;
  
  	list_del(&ev->list);
  	kfree(ev);
   out:
  	mutex_unlock(&data->mtx);
  	return ret;
  }
  
  static ssize_t rfkill_fop_write(struct file *file, const char __user *buf,
  				size_t count, loff_t *pos)
  {
  	struct rfkill *rfkill;
  	struct rfkill_event ev;

  	int ret;

  
  	/* we don't need the 'hard' variable but accept it */

  	if (count < RFKILL_EVENT_SIZE_V1 - 1)

  		return -EINVAL;

  	/*
  	 * Copy as much data as we can accept into our 'ev' buffer,
  	 * but tell userspace how much we've copied so it can determine
  	 * our API version even in a write() call, if it cares.
  	 */
  	count = min(count, sizeof(ev));
  	if (copy_from_user(&ev, buf, count))

  		return -EFAULT;

  	if (ev.type >= NUM_RFKILL_TYPES)
  		return -EINVAL;
  
  	mutex_lock(&rfkill_global_mutex);

  	switch (ev.op) {
  	case RFKILL_OP_CHANGE_ALL:

  		rfkill_update_global_state(ev.type, ev.soft);

  		list_for_each_entry(rfkill, &rfkill_list, node)
  			if (rfkill->type == ev.type ||
  			    ev.type == RFKILL_TYPE_ALL)
  				rfkill_set_block(rfkill, ev.soft);
  		ret = 0;
  		break;
  	case RFKILL_OP_CHANGE:
  		list_for_each_entry(rfkill, &rfkill_list, node)
  			if (rfkill->idx == ev.idx &&
  			    (rfkill->type == ev.type ||
  			     ev.type == RFKILL_TYPE_ALL))
  				rfkill_set_block(rfkill, ev.soft);
  		ret = 0;
  		break;
  	default:
  		ret = -EINVAL;
  		break;

  	}

  	mutex_unlock(&rfkill_global_mutex);

  	return ret ?: count;

  }
  
  static int rfkill_fop_release(struct inode *inode, struct file *file)
  {
  	struct rfkill_data *data = file->private_data;
  	struct rfkill_int_event *ev, *tmp;
  
  	mutex_lock(&rfkill_global_mutex);
  	list_del(&data->list);
  	mutex_unlock(&rfkill_global_mutex);
  
  	mutex_destroy(&data->mtx);
  	list_for_each_entry_safe(ev, tmp, &data->events, list)
  		kfree(ev);
  
  #ifdef CONFIG_RFKILL_INPUT
  	if (data->input_handler)

  		if (atomic_dec_return(&rfkill_input_disabled) == 0)
  			printk(KERN_DEBUG "rfkill: input handler enabled
  ");

  #endif
  
  	kfree(data);
  
  	return 0;
  }
  
  #ifdef CONFIG_RFKILL_INPUT
  static long rfkill_fop_ioctl(struct file *file, unsigned int cmd,
  			     unsigned long arg)
  {
  	struct rfkill_data *data = file->private_data;
  
  	if (_IOC_TYPE(cmd) != RFKILL_IOC_MAGIC)
  		return -ENOSYS;
  
  	if (_IOC_NR(cmd) != RFKILL_IOC_NOINPUT)
  		return -ENOSYS;
  
  	mutex_lock(&data->mtx);
  
  	if (!data->input_handler) {

  		if (atomic_inc_return(&rfkill_input_disabled) == 1)
  			printk(KERN_DEBUG "rfkill: input handler disabled
  ");

  		data->input_handler = true;
  	}
  
  	mutex_unlock(&data->mtx);
  
  	return 0;
  }
  #endif
  
  static const struct file_operations rfkill_fops = {

  	.owner		= THIS_MODULE,

  	.open		= rfkill_fop_open,
  	.read		= rfkill_fop_read,
  	.write		= rfkill_fop_write,
  	.poll		= rfkill_fop_poll,
  	.release	= rfkill_fop_release,
  #ifdef CONFIG_RFKILL_INPUT
  	.unlocked_ioctl	= rfkill_fop_ioctl,
  	.compat_ioctl	= rfkill_fop_ioctl,
  #endif

  	.llseek		= no_llseek,

  };
  
  static struct miscdevice rfkill_miscdev = {
  	.name	= "rfkill",
  	.fops	= &rfkill_fops,
  	.minor	= MISC_DYNAMIC_MINOR,
  };

  
  static int __init rfkill_init(void)
  {
  	int error;

  	rfkill_update_global_state(RFKILL_TYPE_ALL, !rfkill_default_state);

  
  	error = class_register(&rfkill_class);
  	if (error)

  		goto error_class;

  	error = misc_register(&rfkill_miscdev);

  	if (error)
  		goto error_misc;

  	error = rfkill_any_led_trigger_register();
  	if (error)
  		goto error_led_trigger;

  #ifdef CONFIG_RFKILL_INPUT
  	error = rfkill_handler_init();

  	if (error)
  		goto error_input;

  #endif

  	return 0;

  #ifdef CONFIG_RFKILL_INPUT

  error_input:

  	rfkill_any_led_trigger_unregister();

  #endif

  error_led_trigger:
  	misc_deregister(&rfkill_miscdev);

  error_misc:
  	class_unregister(&rfkill_class);
  error_class:

  	return error;
  }
  subsys_initcall(rfkill_init);
  
  static void __exit rfkill_exit(void)
  {
  #ifdef CONFIG_RFKILL_INPUT
  	rfkill_handler_exit();
  #endif

  	rfkill_any_led_trigger_unregister();

  	misc_deregister(&rfkill_miscdev);

  	class_unregister(&rfkill_class);
  }
  module_exit(rfkill_exit);