rfkill: rewrite
This patch completely rewrites the rfkill core to address
the following deficiencies:
* all rfkill drivers need to implement polling where necessary
rather than having one central implementation
* updating the rfkill state cannot be done from arbitrary
contexts, forcing drivers to use schedule_work and requiring
lots of code
* rfkill drivers need to keep track of soft/hard blocked
internally -- the core should do this
* the rfkill API has many unexpected quirks, for example being
asymmetric wrt. alloc/free and register/unregister
* rfkill can call back into a driver from within a function the
driver called -- this is prone to deadlocks and generally
should be avoided
* rfkill-input pointlessly is a separate module
* drivers need to #ifdef rfkill functions (unless they want to
depend on or select RFKILL) -- rfkill should provide inlines
that do nothing if it isn't compiled in
* the rfkill structure is not opaque -- drivers need to initialise
it correctly (lots of sanity checking code required) -- instead
force drivers to pass the right variables to rfkill_alloc()
* the documentation is hard to read because it always assumes the
reader is completely clueless and contains way TOO MANY CAPS
* the rfkill code needlessly uses a lot of locks and atomic
operations in locked sections
* fix LED trigger to actually change the LED when the radio state
changes -- this wasn't done before
Tested-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br> [thinkpad]
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/rfkill/core.c b/net/rfkill/core.c
new file mode 100644
index 0000000..30a6f8d
--- /dev/null
+++ b/net/rfkill/core.c
@@ -0,0 +1,896 @@
+/*
+ * 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, write to the
+ * Free Software Foundation, Inc.,
+ * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#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/spinlock.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;
+
+ const char *name;
+ enum rfkill_type type;
+
+ unsigned long state;
+
+ bool registered;
+ 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;
+};
+#define to_rfkill(d) container_of(d, struct rfkill, dev)
+
+
+
+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 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, def;
+} rfkill_global_states[NUM_RFKILL_TYPES];
+
+static unsigned long rfkill_states_default_locked;
+
+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);
+}
+#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)
+{
+}
+#endif /* CONFIG_RFKILL_LEDS */
+
+static void rfkill_uevent(struct rfkill *rfkill)
+{
+ if (!rfkill->registered || rfkill->suspended)
+ return;
+
+ kobject_uevent(&rfkill->dev.kobj, KOBJ_CHANGE);
+}
+
+static bool __rfkill_set_hw_state(struct rfkill *rfkill,
+ bool blocked, bool *change)
+{
+ unsigned long flags;
+ bool prev, any;
+
+ 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;
+ *change = prev != blocked;
+ any = rfkill->state & RFKILL_BLOCK_ANY;
+ spin_unlock_irqrestore(&rfkill->lock, flags);
+
+ rfkill_led_trigger_event(rfkill);
+
+ return any;
+}
+
+/**
+ * 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;
+ int err;
+
+ /*
+ * 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);
+ if (rfkill->state & RFKILL_BLOCK_SW)
+ 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);
+
+ if (unlikely(rfkill->dev.power.power_state.event & PM_EVENT_SLEEP))
+ return;
+
+ err = rfkill->ops->set_block(rfkill->data, blocked);
+
+ spin_lock_irqsave(&rfkill->lock, flags);
+ if (err) {
+ /*
+ * Failed -- reset status to _prev, this may be different
+ * from what set 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;
+ spin_unlock_irqrestore(&rfkill->lock, flags);
+
+ rfkill_led_trigger_event(rfkill);
+ rfkill_uevent(rfkill);
+}
+
+/**
+ * __rfkill_switch_all - Toggle state of all switches of given type
+ * @type: type of interfaces to be affected
+ * @state: the new state
+ *
+ * This function sets the state of all switches of given type,
+ * unless a specific switch is claimed by userspace (in which case,
+ * that switch is left alone) or suspended.
+ *
+ * Caller must have acquired rfkill_global_mutex.
+ */
+static void __rfkill_switch_all(const enum rfkill_type type, bool blocked)
+{
+ struct rfkill *rfkill;
+
+ rfkill_global_states[type].cur = blocked;
+ list_for_each_entry(rfkill, &rfkill_list, node) {
+ if (rfkill->type != type)
+ continue;
+
+ rfkill_set_block(rfkill, blocked);
+ }
+}
+
+/**
+ * rfkill_switch_all - Toggle state of all switches of given type
+ * @type: type of interfaces to be affected
+ * @state: 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)
+{
+ 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;
+
+ 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].def = 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;
+
+ 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].def);
+ 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)
+{
+ 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;
+}
+
+void rfkill_set_global_sw_state(const enum rfkill_type type, bool blocked)
+{
+ mutex_lock(&rfkill_global_mutex);
+
+ /* don't allow unblock when epo */
+ if (rfkill_epo_lock_active && !blocked)
+ goto out;
+
+ /* too late */
+ if (rfkill_states_default_locked & BIT(type))
+ goto out;
+
+ rfkill_states_default_locked |= BIT(type);
+
+ rfkill_global_states[type].cur = blocked;
+ rfkill_global_states[type].def = blocked;
+ out:
+ mutex_unlock(&rfkill_global_mutex);
+}
+EXPORT_SYMBOL(rfkill_set_global_sw_state);
+
+
+bool rfkill_set_hw_state(struct rfkill *rfkill, bool blocked)
+{
+ bool ret, change;
+
+ ret = __rfkill_set_hw_state(rfkill, blocked, &change);
+
+ if (!rfkill->registered)
+ return ret;
+
+ if (change)
+ 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);
+
+ return blocked;
+}
+EXPORT_SYMBOL(rfkill_set_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);
+
+ spin_unlock_irqrestore(&rfkill->lock, flags);
+
+ if (!rfkill->registered)
+ return;
+
+ if (swprev != sw || hwprev != hw)
+ schedule_work(&rfkill->uevent_work);
+
+ rfkill_led_trigger_event(rfkill);
+}
+EXPORT_SYMBOL(rfkill_set_states);
+
+static ssize_t rfkill_name_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct rfkill *rfkill = to_rfkill(dev);
+
+ return sprintf(buf, "%s\n", rfkill->name);
+}
+
+static const char *rfkill_get_type_str(enum rfkill_type type)
+{
+ switch (type) {
+ case RFKILL_TYPE_WLAN:
+ return "wlan";
+ case RFKILL_TYPE_BLUETOOTH:
+ return "bluetooth";
+ case RFKILL_TYPE_UWB:
+ return "ultrawideband";
+ case RFKILL_TYPE_WIMAX:
+ return "wimax";
+ case RFKILL_TYPE_WWAN:
+ return "wwan";
+ default:
+ BUG();
+ }
+
+ BUILD_BUG_ON(NUM_RFKILL_TYPES != RFKILL_TYPE_WWAN + 1);
+}
+
+static ssize_t rfkill_type_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct rfkill *rfkill = to_rfkill(dev);
+
+ return sprintf(buf, "%s\n", rfkill_get_type_str(rfkill->type));
+}
+
+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 rfkill_state_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct rfkill *rfkill = to_rfkill(dev);
+ unsigned long flags;
+ u32 state;
+
+ spin_lock_irqsave(&rfkill->lock, flags);
+ state = rfkill->state;
+ spin_unlock_irqrestore(&rfkill->lock, flags);
+
+ return sprintf(buf, "%d\n", user_state_from_blocked(state));
+}
+
+static ssize_t rfkill_state_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ /*
+ * The intention was that userspace can only take control over
+ * a given device when/if rfkill-input doesn't control it due
+ * to user_claim. Since user_claim is currently unsupported,
+ * we never support changing the state from userspace -- this
+ * can be implemented again later.
+ */
+
+ return -EPERM;
+}
+
+static ssize_t rfkill_claim_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ return sprintf(buf, "%d\n", 0);
+}
+
+static ssize_t rfkill_claim_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ return -EOPNOTSUPP;
+}
+
+static struct device_attribute rfkill_dev_attrs[] = {
+ __ATTR(name, S_IRUGO, rfkill_name_show, NULL),
+ __ATTR(type, S_IRUGO, rfkill_type_show, NULL),
+ __ATTR(state, S_IRUGO|S_IWUSR, rfkill_state_show, rfkill_state_store),
+ __ATTR(claim, S_IRUGO|S_IWUSR, rfkill_claim_show, rfkill_claim_store),
+ __ATTR_NULL
+};
+
+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_get_type_str(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;
+
+ 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;
+
+ schedule_work(&rfkill->poll_work.work);
+}
+EXPORT_SYMBOL(rfkill_resume_polling);
+
+static int rfkill_suspend(struct device *dev, pm_message_t state)
+{
+ struct rfkill *rfkill = to_rfkill(dev);
+
+ rfkill_pause_polling(rfkill);
+
+ rfkill->suspended = true;
+
+ return 0;
+}
+
+static int rfkill_resume(struct device *dev)
+{
+ struct rfkill *rfkill = to_rfkill(dev);
+ bool cur;
+
+ mutex_lock(&rfkill_global_mutex);
+ cur = rfkill_global_states[rfkill->type].cur;
+ rfkill_set_block(rfkill, cur);
+ mutex_unlock(&rfkill_global_mutex);
+
+ rfkill->suspended = false;
+
+ schedule_work(&rfkill->uevent_work);
+
+ rfkill_resume_polling(rfkill);
+
+ return 0;
+}
+
+static struct class rfkill_class = {
+ .name = "rfkill",
+ .dev_release = rfkill_release,
+ .dev_attrs = rfkill_dev_attrs,
+ .dev_uevent = rfkill_dev_uevent,
+ .suspend = rfkill_suspend,
+ .resume = rfkill_resume,
+};
+
+
+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 >= NUM_RFKILL_TYPES))
+ return NULL;
+
+ rfkill = kzalloc(sizeof(*rfkill), GFP_KERNEL);
+ if (!rfkill)
+ return NULL;
+
+ spin_lock_init(&rfkill->lock);
+ INIT_LIST_HEAD(&rfkill->node);
+ rfkill->type = type;
+ 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);
+
+ schedule_delayed_work(&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);
+
+ rfkill_uevent(rfkill);
+}
+
+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;
+ }
+
+ dev_set_name(dev, "rfkill%lu", rfkill_no);
+ rfkill_no++;
+
+ if (!(rfkill_states_default_locked & BIT(rfkill->type))) {
+ /* first of its kind */
+ BUILD_BUG_ON(NUM_RFKILL_TYPES >
+ sizeof(rfkill_states_default_locked) * 8);
+ rfkill_states_default_locked |= BIT(rfkill->type);
+ rfkill_global_states[rfkill->type].cur =
+ rfkill_global_states[rfkill->type].def;
+ }
+
+ 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;
+
+ if (rfkill->ops->poll) {
+ INIT_DELAYED_WORK(&rfkill->poll_work, rfkill_poll);
+ schedule_delayed_work(&rfkill->poll_work,
+ round_jiffies_relative(POLL_INTERVAL));
+ }
+
+ INIT_WORK(&rfkill->uevent_work, rfkill_uevent_work);
+
+ INIT_WORK(&rfkill->sync_work, rfkill_sync_work);
+ schedule_work(&rfkill->sync_work);
+
+ 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);
+ list_del_init(&rfkill->node);
+ 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 __init rfkill_init(void)
+{
+ int error;
+ int i;
+
+ for (i = 0; i < NUM_RFKILL_TYPES; i++)
+ rfkill_global_states[i].def = !rfkill_default_state;
+
+ error = class_register(&rfkill_class);
+ if (error)
+ goto out;
+
+#ifdef CONFIG_RFKILL_INPUT
+ error = rfkill_handler_init();
+ if (error)
+ class_unregister(&rfkill_class);
+#endif
+
+ out:
+ return error;
+}
+subsys_initcall(rfkill_init);
+
+static void __exit rfkill_exit(void)
+{
+#ifdef CONFIG_RFKILL_INPUT
+ rfkill_handler_exit();
+#endif
+ class_unregister(&rfkill_class);
+}
+module_exit(rfkill_exit);