From 19d337dff95cbf76edd3ad95c0cee2732c3e1ec5 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Tue, 2 Jun 2009 13:01:37 +0200 Subject: 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 Signed-off-by: Henrique de Moraes Holschuh [thinkpad] Signed-off-by: Johannes Berg Signed-off-by: John W. Linville --- net/rfkill/rfkill.c | 855 ---------------------------------------------------- 1 file changed, 855 deletions(-) delete mode 100644 net/rfkill/rfkill.c (limited to 'net/rfkill/rfkill.c') diff --git a/net/rfkill/rfkill.c b/net/rfkill/rfkill.c deleted file mode 100644 index 4f5a83183c9..00000000000 --- a/net/rfkill/rfkill.c +++ /dev/null @@ -1,855 +0,0 @@ -/* - * Copyright (C) 2006 - 2007 Ivo van Doorn - * Copyright (C) 2007 Dmitry Torokhov - * - * 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 -#include -#include -#include -#include -#include -#include -#include - -/* Get declaration of rfkill_switch_all() to shut up sparse. */ -#include "rfkill-input.h" - - -MODULE_AUTHOR("Ivo van Doorn "); -MODULE_VERSION("1.0"); -MODULE_DESCRIPTION("RF switch support"); -MODULE_LICENSE("GPL"); - -static LIST_HEAD(rfkill_list); /* list of registered rf switches */ -static DEFINE_MUTEX(rfkill_global_mutex); - -static unsigned int rfkill_default_state = RFKILL_STATE_UNBLOCKED; -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"); - -struct rfkill_gsw_state { - enum rfkill_state current_state; - enum rfkill_state default_state; -}; - -static struct rfkill_gsw_state rfkill_global_states[RFKILL_TYPE_MAX]; -static unsigned long rfkill_states_lockdflt[BITS_TO_LONGS(RFKILL_TYPE_MAX)]; -static bool rfkill_epo_lock_active; - - -#ifdef CONFIG_RFKILL_LEDS -static void rfkill_led_trigger(struct rfkill *rfkill, - enum rfkill_state state) -{ - struct led_trigger *led = &rfkill->led_trigger; - - if (!led->name) - return; - if (state != RFKILL_STATE_UNBLOCKED) - led_trigger_event(led, LED_OFF); - else - led_trigger_event(led, LED_FULL); -} - -static void rfkill_led_trigger_activate(struct led_classdev *led) -{ - struct rfkill *rfkill = container_of(led->trigger, - struct rfkill, led_trigger); - - rfkill_led_trigger(rfkill, rfkill->state); -} -#else -static inline void rfkill_led_trigger(struct rfkill *rfkill, - enum rfkill_state state) -{ -} -#endif /* CONFIG_RFKILL_LEDS */ - -static void rfkill_uevent(struct rfkill *rfkill) -{ - kobject_uevent(&rfkill->dev.kobj, KOBJ_CHANGE); -} - -static void update_rfkill_state(struct rfkill *rfkill) -{ - enum rfkill_state newstate, oldstate; - - if (rfkill->get_state) { - mutex_lock(&rfkill->mutex); - if (!rfkill->get_state(rfkill->data, &newstate)) { - oldstate = rfkill->state; - rfkill->state = newstate; - if (oldstate != newstate) - rfkill_uevent(rfkill); - } - mutex_unlock(&rfkill->mutex); - } - rfkill_led_trigger(rfkill, rfkill->state); -} - -/** - * rfkill_toggle_radio - wrapper for toggle_radio hook - * @rfkill: the rfkill struct to use - * @force: calls toggle_radio even if cache says it is not needed, - * and also makes sure notifications of the state will be - * sent even if it didn't change - * @state: the new state to call toggle_radio() with - * - * Calls rfkill->toggle_radio, enforcing the API for toggle_radio - * calls and handling all the red tape such as issuing notifications - * if the call is successful. - * - * Suspended devices are not touched at all, and -EAGAIN is returned. - * - * Note that the @force parameter cannot override a (possibly cached) - * state of RFKILL_STATE_HARD_BLOCKED. Any device making use of - * RFKILL_STATE_HARD_BLOCKED implements either get_state() or - * rfkill_force_state(), so the cache either is bypassed or valid. - * - * Note that we do call toggle_radio for RFKILL_STATE_SOFT_BLOCKED - * even if the radio is in RFKILL_STATE_HARD_BLOCKED state, so as to - * give the driver a hint that it should double-BLOCK the transmitter. - * - * Caller must have acquired rfkill->mutex. - */ -static int rfkill_toggle_radio(struct rfkill *rfkill, - enum rfkill_state state, - int force) -{ - int retval = 0; - enum rfkill_state oldstate, newstate; - - if (unlikely(rfkill->dev.power.power_state.event & PM_EVENT_SLEEP)) - return -EBUSY; - - oldstate = rfkill->state; - - if (rfkill->get_state && !force && - !rfkill->get_state(rfkill->data, &newstate)) { - rfkill->state = newstate; - } - - switch (state) { - case RFKILL_STATE_HARD_BLOCKED: - /* typically happens when refreshing hardware state, - * such as on resume */ - state = RFKILL_STATE_SOFT_BLOCKED; - break; - case RFKILL_STATE_UNBLOCKED: - /* force can't override this, only rfkill_force_state() can */ - if (rfkill->state == RFKILL_STATE_HARD_BLOCKED) - return -EPERM; - break; - case RFKILL_STATE_SOFT_BLOCKED: - /* nothing to do, we want to give drivers the hint to double - * BLOCK even a transmitter that is already in state - * RFKILL_STATE_HARD_BLOCKED */ - break; - default: - WARN(1, KERN_WARNING - "rfkill: illegal state %d passed as parameter " - "to rfkill_toggle_radio\n", state); - return -EINVAL; - } - - if (force || state != rfkill->state) { - retval = rfkill->toggle_radio(rfkill->data, state); - /* never allow a HARD->SOFT downgrade! */ - if (!retval && rfkill->state != RFKILL_STATE_HARD_BLOCKED) - rfkill->state = state; - } - - if (force || rfkill->state != oldstate) - rfkill_uevent(rfkill); - - rfkill_led_trigger(rfkill, rfkill->state); - return retval; -} - -/** - * __rfkill_switch_all - Toggle state of all switches of given type - * @type: type of interfaces to be affected - * @state: the new state - * - * This function toggles 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, - const enum rfkill_state state) -{ - struct rfkill *rfkill; - - if (WARN((state >= RFKILL_STATE_MAX || type >= RFKILL_TYPE_MAX), - KERN_WARNING - "rfkill: illegal state %d or type %d " - "passed as parameter to __rfkill_switch_all\n", - state, type)) - return; - - rfkill_global_states[type].current_state = state; - list_for_each_entry(rfkill, &rfkill_list, node) { - if (rfkill->type == type) { - mutex_lock(&rfkill->mutex); - rfkill_toggle_radio(rfkill, state, 0); - mutex_unlock(&rfkill->mutex); - rfkill_led_trigger(rfkill, rfkill->state); - } - } -} - -/** - * 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, enum rfkill_state state) -{ - mutex_lock(&rfkill_global_mutex); - if (!rfkill_epo_lock_active) - __rfkill_switch_all(type, state); - mutex_unlock(&rfkill_global_mutex); -} -EXPORT_SYMBOL(rfkill_switch_all); - -/** - * 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) { - mutex_lock(&rfkill->mutex); - rfkill_toggle_radio(rfkill, RFKILL_STATE_SOFT_BLOCKED, 1); - mutex_unlock(&rfkill->mutex); - } - for (i = 0; i < RFKILL_TYPE_MAX; i++) { - rfkill_global_states[i].default_state = - rfkill_global_states[i].current_state; - rfkill_global_states[i].current_state = - RFKILL_STATE_SOFT_BLOCKED; - } - mutex_unlock(&rfkill_global_mutex); - rfkill_led_trigger(rfkill, rfkill->state); -} -EXPORT_SYMBOL_GPL(rfkill_epo); - -/** - * 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 < RFKILL_TYPE_MAX; i++) - __rfkill_switch_all(i, rfkill_global_states[i].default_state); - mutex_unlock(&rfkill_global_mutex); -} -EXPORT_SYMBOL_GPL(rfkill_restore_states); - -/** - * 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); -} -EXPORT_SYMBOL_GPL(rfkill_remove_epo_lock); - -/** - * 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; -} -EXPORT_SYMBOL_GPL(rfkill_is_epo_lock_active); - -/** - * rfkill_get_global_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. - */ -enum rfkill_state rfkill_get_global_state(const enum rfkill_type type) -{ - return rfkill_global_states[type].current_state; -} -EXPORT_SYMBOL_GPL(rfkill_get_global_state); - -/** - * rfkill_force_state - Force the internal rfkill radio state - * @rfkill: pointer to the rfkill class to modify. - * @state: the current radio state the class should be forced to. - * - * This function updates the internal state of the radio cached - * by the rfkill class. It should be used when the driver gets - * a notification by the firmware/hardware of the current *real* - * state of the radio rfkill switch. - * - * Devices which are subject to external changes on their rfkill - * state (such as those caused by a hardware rfkill line) MUST - * have their driver arrange to call rfkill_force_state() as soon - * as possible after such a change. - * - * This function may not be called from an atomic context. - */ -int rfkill_force_state(struct rfkill *rfkill, enum rfkill_state state) -{ - enum rfkill_state oldstate; - - BUG_ON(!rfkill); - if (WARN((state >= RFKILL_STATE_MAX), - KERN_WARNING - "rfkill: illegal state %d passed as parameter " - "to rfkill_force_state\n", state)) - return -EINVAL; - - mutex_lock(&rfkill->mutex); - - oldstate = rfkill->state; - rfkill->state = state; - - if (state != oldstate) - rfkill_uevent(rfkill); - - mutex_unlock(&rfkill->mutex); - rfkill_led_trigger(rfkill, rfkill->state); - - return 0; -} -EXPORT_SYMBOL(rfkill_force_state); - -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(); - } -} - -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 ssize_t rfkill_state_show(struct device *dev, - struct device_attribute *attr, - char *buf) -{ - struct rfkill *rfkill = to_rfkill(dev); - - update_rfkill_state(rfkill); - return sprintf(buf, "%d\n", rfkill->state); -} - -static ssize_t rfkill_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 error; - - if (!capable(CAP_NET_ADMIN)) - return -EPERM; - - error = strict_strtoul(buf, 0, &state); - if (error) - return error; - - /* RFKILL_STATE_HARD_BLOCKED is illegal here... */ - if (state != RFKILL_STATE_UNBLOCKED && - state != RFKILL_STATE_SOFT_BLOCKED) - return -EINVAL; - - error = mutex_lock_killable(&rfkill->mutex); - if (error) - return error; - - if (!rfkill_epo_lock_active) - error = rfkill_toggle_radio(rfkill, state, 0); - else - error = -EPERM; - - mutex_unlock(&rfkill->mutex); - - return error ? error : count; -} - -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); - module_put(THIS_MODULE); -} - -#ifdef CONFIG_PM -static int rfkill_suspend(struct device *dev, pm_message_t state) -{ - struct rfkill *rfkill = to_rfkill(dev); - - /* mark class device as suspended */ - if (dev->power.power_state.event != state.event) - dev->power.power_state = state; - - /* store state for the resume handler */ - rfkill->state_for_resume = rfkill->state; - - return 0; -} - -static int rfkill_resume(struct device *dev) -{ - struct rfkill *rfkill = to_rfkill(dev); - enum rfkill_state newstate; - - if (dev->power.power_state.event != PM_EVENT_ON) { - mutex_lock(&rfkill->mutex); - - dev->power.power_state.event = PM_EVENT_ON; - - /* - * rfkill->state could have been modified before we got - * called, and won't be updated by rfkill_toggle_radio() - * in force mode. Sync it FIRST. - */ - if (rfkill->get_state && - !rfkill->get_state(rfkill->data, &newstate)) - rfkill->state = newstate; - - /* - * If we are under EPO, kick transmitter offline, - * otherwise restore to pre-suspend state. - * - * Issue a notification in any case - */ - rfkill_toggle_radio(rfkill, - rfkill_epo_lock_active ? - RFKILL_STATE_SOFT_BLOCKED : - rfkill->state_for_resume, - 1); - - mutex_unlock(&rfkill->mutex); - rfkill_led_trigger(rfkill, rfkill->state); - } - - return 0; -} -#else -#define rfkill_suspend NULL -#define rfkill_resume NULL -#endif - -static int rfkill_dev_uevent(struct device *dev, struct kobj_uevent_env *env) -{ - struct rfkill *rfkill = to_rfkill(dev); - 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; - error = add_uevent_var(env, "RFKILL_STATE=%d", rfkill->state); - return error; -} - -static struct class rfkill_class = { - .name = "rfkill", - .dev_release = rfkill_release, - .dev_attrs = rfkill_dev_attrs, - .suspend = rfkill_suspend, - .resume = rfkill_resume, - .dev_uevent = rfkill_dev_uevent, -}; - -static int rfkill_check_duplicity(const struct rfkill *rfkill) -{ - struct rfkill *p; - unsigned long seen[BITS_TO_LONGS(RFKILL_TYPE_MAX)]; - - memset(seen, 0, sizeof(seen)); - - list_for_each_entry(p, &rfkill_list, node) { - if (WARN((p == rfkill), KERN_WARNING - "rfkill: illegal attempt to register " - "an already registered rfkill struct\n")) - return -EEXIST; - set_bit(p->type, seen); - } - - /* 0: first switch of its kind */ - return (test_bit(rfkill->type, seen)) ? 1 : 0; -} - -static int rfkill_add_switch(struct rfkill *rfkill) -{ - int error; - - mutex_lock(&rfkill_global_mutex); - - error = rfkill_check_duplicity(rfkill); - if (error < 0) - goto unlock_out; - - if (!error) { - /* lock default after first use */ - set_bit(rfkill->type, rfkill_states_lockdflt); - rfkill_global_states[rfkill->type].current_state = - rfkill_global_states[rfkill->type].default_state; - } - - rfkill_toggle_radio(rfkill, - rfkill_global_states[rfkill->type].current_state, - 0); - - list_add_tail(&rfkill->node, &rfkill_list); - - error = 0; -unlock_out: - mutex_unlock(&rfkill_global_mutex); - - return error; -} - -static void rfkill_remove_switch(struct rfkill *rfkill) -{ - mutex_lock(&rfkill_global_mutex); - list_del_init(&rfkill->node); - mutex_unlock(&rfkill_global_mutex); - - mutex_lock(&rfkill->mutex); - rfkill_toggle_radio(rfkill, RFKILL_STATE_SOFT_BLOCKED, 1); - mutex_unlock(&rfkill->mutex); -} - -/** - * rfkill_allocate - allocate memory for rfkill structure. - * @parent: device that has rf switch on it - * @type: type of the switch (RFKILL_TYPE_*) - * - * This function should be called by the network driver when it needs - * rfkill structure. Once the structure is allocated the driver should - * finish its initialization by setting the name, private data, enable_radio - * and disable_radio methods and then register it with rfkill_register(). - * - * NOTE: If registration fails the structure shoudl be freed by calling - * rfkill_free() otherwise rfkill_unregister() should be used. - */ -struct rfkill * __must_check rfkill_allocate(struct device *parent, - enum rfkill_type type) -{ - struct rfkill *rfkill; - struct device *dev; - - if (WARN((type >= RFKILL_TYPE_MAX), - KERN_WARNING - "rfkill: illegal type %d passed as parameter " - "to rfkill_allocate\n", type)) - return NULL; - - rfkill = kzalloc(sizeof(struct rfkill), GFP_KERNEL); - if (!rfkill) - return NULL; - - mutex_init(&rfkill->mutex); - INIT_LIST_HEAD(&rfkill->node); - rfkill->type = type; - - dev = &rfkill->dev; - dev->class = &rfkill_class; - dev->parent = parent; - device_initialize(dev); - - __module_get(THIS_MODULE); - - return rfkill; -} -EXPORT_SYMBOL(rfkill_allocate); - -/** - * rfkill_free - Mark rfkill structure for deletion - * @rfkill: rfkill structure to be destroyed - * - * Decrements reference count of the rfkill structure so it is destroyed. - * Note that rfkill_free() should _not_ be called after rfkill_unregister(). - */ -void rfkill_free(struct rfkill *rfkill) -{ - if (rfkill) - put_device(&rfkill->dev); -} -EXPORT_SYMBOL(rfkill_free); - -static void rfkill_led_trigger_register(struct rfkill *rfkill) -{ -#ifdef CONFIG_RFKILL_LEDS - int error; - - if (!rfkill->led_trigger.name) - rfkill->led_trigger.name = dev_name(&rfkill->dev); - if (!rfkill->led_trigger.activate) - rfkill->led_trigger.activate = rfkill_led_trigger_activate; - error = led_trigger_register(&rfkill->led_trigger); - if (error) - rfkill->led_trigger.name = NULL; -#endif /* CONFIG_RFKILL_LEDS */ -} - -static void rfkill_led_trigger_unregister(struct rfkill *rfkill) -{ -#ifdef CONFIG_RFKILL_LEDS - if (rfkill->led_trigger.name) { - led_trigger_unregister(&rfkill->led_trigger); - rfkill->led_trigger.name = NULL; - } -#endif -} - -/** - * rfkill_register - Register a rfkill structure. - * @rfkill: rfkill structure to be registered - * - * This function should be called by the network driver when the rfkill - * structure needs to be registered. Immediately from registration the - * switch driver should be able to service calls to toggle_radio. - */ -int __must_check rfkill_register(struct rfkill *rfkill) -{ - static atomic_t rfkill_no = ATOMIC_INIT(0); - struct device *dev = &rfkill->dev; - int error; - - if (WARN((!rfkill || !rfkill->toggle_radio || - rfkill->type >= RFKILL_TYPE_MAX || - rfkill->state >= RFKILL_STATE_MAX), - KERN_WARNING - "rfkill: attempt to register a " - "badly initialized rfkill struct\n")) - return -EINVAL; - - dev_set_name(dev, "rfkill%ld", (long)atomic_inc_return(&rfkill_no) - 1); - - rfkill_led_trigger_register(rfkill); - - error = rfkill_add_switch(rfkill); - if (error) { - rfkill_led_trigger_unregister(rfkill); - return error; - } - - error = device_add(dev); - if (error) { - rfkill_remove_switch(rfkill); - rfkill_led_trigger_unregister(rfkill); - return error; - } - - return 0; -} -EXPORT_SYMBOL(rfkill_register); - -/** - * rfkill_unregister - Unregister a rfkill structure. - * @rfkill: rfkill structure to be unregistered - * - * This function should be called by the network driver during device - * teardown to destroy rfkill structure. Note that rfkill_free() should - * _not_ be called after rfkill_unregister(). - */ -void rfkill_unregister(struct rfkill *rfkill) -{ - BUG_ON(!rfkill); - device_del(&rfkill->dev); - rfkill_remove_switch(rfkill); - rfkill_led_trigger_unregister(rfkill); - put_device(&rfkill->dev); -} -EXPORT_SYMBOL(rfkill_unregister); - -/** - * rfkill_set_default - set initial value for a switch type - * @type - the type of switch to set the default state of - * @state - the new default state for that group of switches - * - * Sets the initial state rfkill should use for a given type. - * The following initial states are allowed: RFKILL_STATE_SOFT_BLOCKED - * and RFKILL_STATE_UNBLOCKED. - * - * This function is meant to be used by platform drivers for platforms - * that can save switch state across power down/reboot. - * - * The default state for each switch type can be changed exactly once. - * After a switch of that type is registered, the default state cannot - * be changed anymore. This guards against multiple drivers it the - * same platform trying to set the initial switch default state, which - * is not allowed. - * - * Returns -EPERM if the state has already been set once or is in use, - * so drivers likely want to either ignore or at most printk(KERN_NOTICE) - * if this function returns -EPERM. - * - * Returns 0 if the new default state was set, or an error if it - * could not be set. - */ -int rfkill_set_default(enum rfkill_type type, enum rfkill_state state) -{ - int error; - - if (WARN((type >= RFKILL_TYPE_MAX || - (state != RFKILL_STATE_SOFT_BLOCKED && - state != RFKILL_STATE_UNBLOCKED)), - KERN_WARNING - "rfkill: illegal state %d or type %d passed as " - "parameter to rfkill_set_default\n", state, type)) - return -EINVAL; - - mutex_lock(&rfkill_global_mutex); - - if (!test_and_set_bit(type, rfkill_states_lockdflt)) { - rfkill_global_states[type].default_state = state; - rfkill_global_states[type].current_state = state; - error = 0; - } else - error = -EPERM; - - mutex_unlock(&rfkill_global_mutex); - return error; -} -EXPORT_SYMBOL_GPL(rfkill_set_default); - -/* - * Rfkill module initialization/deinitialization. - */ -static int __init rfkill_init(void) -{ - int error; - int i; - - /* RFKILL_STATE_HARD_BLOCKED is illegal here... */ - if (rfkill_default_state != RFKILL_STATE_SOFT_BLOCKED && - rfkill_default_state != RFKILL_STATE_UNBLOCKED) - return -EINVAL; - - for (i = 0; i < RFKILL_TYPE_MAX; i++) - rfkill_global_states[i].default_state = rfkill_default_state; - - error = class_register(&rfkill_class); - if (error) { - printk(KERN_ERR "rfkill: unable to register rfkill class\n"); - return error; - } - - return 0; -} - -static void __exit rfkill_exit(void) -{ - class_unregister(&rfkill_class); -} - -subsys_initcall(rfkill_init); -module_exit(rfkill_exit); -- cgit v1.2.3