diff options
Diffstat (limited to 'net/rfkill/rfkill.c')
-rw-r--r-- | net/rfkill/rfkill.c | 344 |
1 files changed, 269 insertions, 75 deletions
diff --git a/net/rfkill/rfkill.c b/net/rfkill/rfkill.c index 7a560b78509..f949a482b00 100644 --- a/net/rfkill/rfkill.c +++ b/net/rfkill/rfkill.c @@ -37,14 +37,20 @@ MODULE_DESCRIPTION("RF switch support"); MODULE_LICENSE("GPL"); static LIST_HEAD(rfkill_list); /* list of registered rf switches */ -static DEFINE_MUTEX(rfkill_mutex); +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"); -static enum rfkill_state rfkill_states[RFKILL_TYPE_MAX]; +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 BLOCKING_NOTIFIER_HEAD(rfkill_notifier_list); @@ -70,6 +76,7 @@ static BLOCKING_NOTIFIER_HEAD(rfkill_notifier_list); */ int register_rfkill_notifier(struct notifier_block *nb) { + BUG_ON(!nb); return blocking_notifier_chain_register(&rfkill_notifier_list, nb); } EXPORT_SYMBOL_GPL(register_rfkill_notifier); @@ -85,6 +92,7 @@ EXPORT_SYMBOL_GPL(register_rfkill_notifier); */ int unregister_rfkill_notifier(struct notifier_block *nb) { + BUG_ON(!nb); return blocking_notifier_chain_unregister(&rfkill_notifier_list, nb); } EXPORT_SYMBOL_GPL(unregister_rfkill_notifier); @@ -105,8 +113,19 @@ static void rfkill_led_trigger(struct rfkill *rfkill, #endif /* CONFIG_RFKILL_LEDS */ } +#ifdef CONFIG_RFKILL_LEDS +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); +} +#endif /* CONFIG_RFKILL_LEDS */ + static void notify_rfkill_state_change(struct rfkill *rfkill) { + rfkill_led_trigger(rfkill, rfkill->state); blocking_notifier_call_chain(&rfkill_notifier_list, RFKILL_STATE_CHANGED, rfkill); @@ -130,7 +149,6 @@ static void update_rfkill_state(struct rfkill *rfkill) /** * 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 @@ -141,8 +159,10 @@ static void update_rfkill_state(struct rfkill *rfkill) * calls and handling all the red tape such as issuing notifications * if the call is successful. * - * Note that @force cannot override a (possibly cached) state of - * RFKILL_STATE_HARD_BLOCKED. Any device making use of + * 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. * @@ -150,7 +170,7 @@ static void update_rfkill_state(struct rfkill *rfkill) * 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 aquired rfkill_mutex. + * Caller must have acquired rfkill->mutex. */ static int rfkill_toggle_radio(struct rfkill *rfkill, enum rfkill_state state, @@ -159,6 +179,9 @@ static int rfkill_toggle_radio(struct rfkill *rfkill, 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 && @@ -181,6 +204,11 @@ static int rfkill_toggle_radio(struct rfkill *rfkill, * 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) { @@ -190,59 +218,112 @@ static int rfkill_toggle_radio(struct rfkill *rfkill, rfkill->state = state; } - if (force || rfkill->state != oldstate) { - rfkill_led_trigger(rfkill, rfkill->state); + if (force || rfkill->state != oldstate) notify_rfkill_state_change(rfkill); - } return retval; } /** - * rfkill_switch_all - Toggle state of all switches of given type - * @type: type of interfaces to be affeceted + * __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 state of all switches of given type unless - * a specific switch is claimed by userspace in which case it is - * left alone. + * 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. */ -void rfkill_switch_all(enum rfkill_type type, enum rfkill_state state) +static void __rfkill_switch_all(const enum rfkill_type type, + const enum rfkill_state state) { struct rfkill *rfkill; - mutex_lock(&rfkill_mutex); - - rfkill_states[type] = state; + 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->user_claim) && (rfkill->type == type)) + if ((!rfkill->user_claim) && (rfkill->type == type)) { + mutex_lock(&rfkill->mutex); rfkill_toggle_radio(rfkill, state, 0); + mutex_unlock(&rfkill->mutex); + } } +} - mutex_unlock(&rfkill_mutex); +/** + * 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. + */ +void rfkill_switch_all(enum rfkill_type type, enum rfkill_state state) +{ + mutex_lock(&rfkill_global_mutex); + __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 rfkill devices to RFKILL_STATE_SOFT_BLOCKED, ignoring - * everything in its path but rfkill_mutex. + * 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); - mutex_lock(&rfkill_mutex); 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_mutex); + mutex_unlock(&rfkill_global_mutex); } 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); + + 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_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. @@ -252,15 +333,22 @@ EXPORT_SYMBOL_GPL(rfkill_epo); * a notification by the firmware/hardware of the current *real* * state of the radio rfkill switch. * - * It may not be called from an atomic context. + * 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; - if (state != RFKILL_STATE_SOFT_BLOCKED && - state != RFKILL_STATE_UNBLOCKED && - state != RFKILL_STATE_HARD_BLOCKED) + 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); @@ -328,12 +416,16 @@ static ssize_t rfkill_state_store(struct device *dev, const char *buf, size_t count) { struct rfkill *rfkill = to_rfkill(dev); - unsigned int state = simple_strtoul(buf, NULL, 0); + 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) @@ -353,7 +445,7 @@ static ssize_t rfkill_claim_show(struct device *dev, { struct rfkill *rfkill = to_rfkill(dev); - return sprintf(buf, "%d", rfkill->user_claim); + return sprintf(buf, "%d\n", rfkill->user_claim); } static ssize_t rfkill_claim_store(struct device *dev, @@ -361,34 +453,41 @@ static ssize_t rfkill_claim_store(struct device *dev, const char *buf, size_t count) { struct rfkill *rfkill = to_rfkill(dev); - bool claim = !!simple_strtoul(buf, NULL, 0); + unsigned long claim_tmp; + bool claim; int error; if (!capable(CAP_NET_ADMIN)) return -EPERM; + if (rfkill->user_claim_unsupported) + return -EOPNOTSUPP; + + error = strict_strtoul(buf, 0, &claim_tmp); + if (error) + return error; + claim = !!claim_tmp; + /* * Take the global lock to make sure the kernel is not in * the middle of rfkill_switch_all */ - error = mutex_lock_interruptible(&rfkill_mutex); + error = mutex_lock_interruptible(&rfkill_global_mutex); if (error) return error; - if (rfkill->user_claim_unsupported) { - error = -EOPNOTSUPP; - goto out_unlock; - } if (rfkill->user_claim != claim) { - if (!claim) + if (!claim) { + mutex_lock(&rfkill->mutex); rfkill_toggle_radio(rfkill, - rfkill_states[rfkill->type], - 0); + rfkill_global_states[rfkill->type].current_state, + 0); + mutex_unlock(&rfkill->mutex); + } rfkill->user_claim = claim; } -out_unlock: - mutex_unlock(&rfkill_mutex); + mutex_unlock(&rfkill_global_mutex); return error ? error : count; } @@ -412,21 +511,9 @@ static void rfkill_release(struct device *dev) #ifdef CONFIG_PM static int rfkill_suspend(struct device *dev, pm_message_t state) { - struct rfkill *rfkill = to_rfkill(dev); - - if (dev->power.power_state.event != state.event) { - if (state.event & PM_EVENT_SLEEP) { - /* Stop transmitter, keep state, no notifies */ - update_rfkill_state(rfkill); - - mutex_lock(&rfkill->mutex); - rfkill->toggle_radio(rfkill->data, - RFKILL_STATE_SOFT_BLOCKED); - mutex_unlock(&rfkill->mutex); - } - + /* mark class device as suspended */ + if (dev->power.power_state.event != state.event) dev->power.power_state = state; - } return 0; } @@ -438,13 +525,14 @@ static int rfkill_resume(struct device *dev) if (dev->power.power_state.event != PM_EVENT_ON) { mutex_lock(&rfkill->mutex); + dev->power.power_state.event = PM_EVENT_ON; + /* restore radio state AND notify everybody */ rfkill_toggle_radio(rfkill, rfkill->state, 1); mutex_unlock(&rfkill->mutex); } - dev->power.power_state = PMSG_ON; return 0; } #else @@ -499,25 +587,64 @@ static struct class rfkill_class = { .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); +} + static int rfkill_add_switch(struct rfkill *rfkill) { - mutex_lock(&rfkill_mutex); + int error; + + mutex_lock(&rfkill_global_mutex); - rfkill_toggle_radio(rfkill, rfkill_states[rfkill->type], 0); + 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); - mutex_unlock(&rfkill_mutex); + error = 0; +unlock_out: + mutex_unlock(&rfkill_global_mutex); - return 0; + return error; } static void rfkill_remove_switch(struct rfkill *rfkill) { - mutex_lock(&rfkill_mutex); + 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); + mutex_unlock(&rfkill->mutex); } /** @@ -526,17 +653,25 @@ static void rfkill_remove_switch(struct rfkill *rfkill) * @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 shoud - * finish its initialization by setting name, private data, enable_radio + * 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 *rfkill_allocate(struct device *parent, enum rfkill_type type) +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; @@ -560,7 +695,7 @@ EXPORT_SYMBOL(rfkill_allocate); * rfkill_free - Mark rfkill structure for deletion * @rfkill: rfkill structure to be destroyed * - * Decrements reference count of rfkill structure so it is 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) @@ -575,7 +710,10 @@ static void rfkill_led_trigger_register(struct rfkill *rfkill) #ifdef CONFIG_RFKILL_LEDS int error; - rfkill->led_trigger.name = rfkill->dev.bus_id; + if (!rfkill->led_trigger.name) + rfkill->led_trigger.name = rfkill->dev.bus_id; + 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; @@ -585,8 +723,10 @@ static void rfkill_led_trigger_register(struct rfkill *rfkill) static void rfkill_led_trigger_unregister(struct rfkill *rfkill) { #ifdef CONFIG_RFKILL_LEDS - if (rfkill->led_trigger.name) + if (rfkill->led_trigger.name) { led_trigger_unregister(&rfkill->led_trigger); + rfkill->led_trigger.name = NULL; + } #endif } @@ -598,15 +738,18 @@ static void rfkill_led_trigger_unregister(struct rfkill *rfkill) * structure needs to be registered. Immediately from registration the * switch driver should be able to service calls to toggle_radio. */ -int rfkill_register(struct rfkill *rfkill) +int __must_check rfkill_register(struct rfkill *rfkill) { static atomic_t rfkill_no = ATOMIC_INIT(0); struct device *dev = &rfkill->dev; int error; - if (!rfkill->toggle_radio) - return -EINVAL; - if (rfkill->type >= RFKILL_TYPE_MAX) + 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; snprintf(dev->bus_id, sizeof(dev->bus_id), @@ -622,8 +765,8 @@ int rfkill_register(struct rfkill *rfkill) error = device_add(dev); if (error) { - rfkill_led_trigger_unregister(rfkill); rfkill_remove_switch(rfkill); + rfkill_led_trigger_unregister(rfkill); return error; } @@ -641,6 +784,7 @@ EXPORT_SYMBOL(rfkill_register); */ void rfkill_unregister(struct rfkill *rfkill) { + BUG_ON(!rfkill); device_del(&rfkill->dev); rfkill_remove_switch(rfkill); rfkill_led_trigger_unregister(rfkill); @@ -648,6 +792,56 @@ void rfkill_unregister(struct rfkill *rfkill) } 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; + error = 0; + } else + error = -EPERM; + + mutex_unlock(&rfkill_global_mutex); + return error; +} +EXPORT_SYMBOL_GPL(rfkill_set_default); + /* * Rfkill module initialization/deinitialization. */ @@ -661,8 +855,8 @@ static int __init rfkill_init(void) rfkill_default_state != RFKILL_STATE_UNBLOCKED) return -EINVAL; - for (i = 0; i < ARRAY_SIZE(rfkill_states); i++) - rfkill_states[i] = rfkill_default_state; + for (i = 0; i < RFKILL_TYPE_MAX; i++) + rfkill_global_states[i].default_state = rfkill_default_state; error = class_register(&rfkill_class); if (error) { |