From 9961920199ec88d6b581d3e38502088935925c04 Mon Sep 17 00:00:00 2001 From: Henrique de Moraes Holschuh Date: Sat, 2 Aug 2008 15:10:58 -0300 Subject: [PATCH] rfkill: add default global states (v2) Add a second set of global states, "rfkill_default_states", to track the state that will be used when the first rfkill class of a given type is registered, and also to save "undo" information when rfkill_epo is called. Add a new exported function, rfkill_set_default(), which can be used by platform drivers to restore radio state saved by the platform across reboots or shutdown. Also, fix rfkill_epo to properly update rfkill_states, but still preserve a copy of the state so that we can undo the effect of rfkill_epo later if we want to. Add rfkill_restore_states() to restore rfkill_states from the copy. Signed-off-by: Henrique de Moraes Holschuh Acked-by: Ivo van Doorn Signed-off-by: John W. Linville --- include/linux/rfkill.h | 1 + net/rfkill/rfkill-input.h | 1 + net/rfkill/rfkill.c | 127 ++++++++++++++++++++++++++++++++++---- 3 files changed, 117 insertions(+), 12 deletions(-) diff --git a/include/linux/rfkill.h b/include/linux/rfkill.h index 741d1a62cc3f..aa3c7d5852f6 100644 --- a/include/linux/rfkill.h +++ b/include/linux/rfkill.h @@ -116,6 +116,7 @@ int rfkill_register(struct rfkill *rfkill); void rfkill_unregister(struct rfkill *rfkill); int rfkill_force_state(struct rfkill *rfkill, enum rfkill_state state); +int rfkill_set_default(enum rfkill_type type, enum rfkill_state state); /** * rfkill_state_complement - return complementar state diff --git a/net/rfkill/rfkill-input.h b/net/rfkill/rfkill-input.h index f63d05045685..bbfa646157c6 100644 --- a/net/rfkill/rfkill-input.h +++ b/net/rfkill/rfkill-input.h @@ -13,5 +13,6 @@ void rfkill_switch_all(enum rfkill_type type, enum rfkill_state state); void rfkill_epo(void); +void rfkill_restore_states(void); #endif /* __RFKILL_INPUT_H */ diff --git a/net/rfkill/rfkill.c b/net/rfkill/rfkill.c index 1f23de20a85e..b995fa32cf84 100644 --- a/net/rfkill/rfkill.c +++ b/net/rfkill/rfkill.c @@ -44,7 +44,13 @@ 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); @@ -213,22 +219,22 @@ static int rfkill_toggle_radio(struct rfkill *rfkill, } /** - * rfkill_switch_all - Toggle state of all switches of given type + * __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_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; - + rfkill_global_states[type].current_state = state; list_for_each_entry(rfkill, &rfkill_list, node) { if ((!rfkill->user_claim) && (rfkill->type == type)) { mutex_lock(&rfkill->mutex); @@ -236,7 +242,20 @@ void rfkill_switch_all(enum rfkill_type type, enum rfkill_state state) 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_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_mutex); + __rfkill_switch_all(type, state); mutex_unlock(&rfkill_mutex); } EXPORT_SYMBOL(rfkill_switch_all); @@ -246,10 +265,14 @@ EXPORT_SYMBOL(rfkill_switch_all); * * This kicks all non-suspended rfkill devices to RFKILL_STATE_SOFT_BLOCKED, * ignoring everything in its path but rfkill_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_mutex); list_for_each_entry(rfkill, &rfkill_list, node) { @@ -257,10 +280,34 @@ void rfkill_epo(void) 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); } 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_mutex); + for (i = 0; i < RFKILL_TYPE_MAX; i++) + __rfkill_switch_all(i, rfkill_global_states[i].default_state); + mutex_unlock(&rfkill_mutex); +} +EXPORT_SYMBOL_GPL(rfkill_restore_states); + /** * rfkill_force_state - Force the internal rfkill radio state * @rfkill: pointer to the rfkill class to modify. @@ -406,8 +453,8 @@ static ssize_t rfkill_claim_store(struct device *dev, 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; @@ -554,7 +601,16 @@ static int rfkill_add_switch(struct rfkill *rfkill) if (error < 0) goto unlock_out; - rfkill_toggle_radio(rfkill, rfkill_states[rfkill->type], 0); + 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); @@ -710,6 +766,53 @@ 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 (type >= RFKILL_TYPE_MAX || + (state != RFKILL_STATE_SOFT_BLOCKED && + state != RFKILL_STATE_UNBLOCKED)) + return -EINVAL; + + mutex_lock(&rfkill_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_mutex); + return error; +} +EXPORT_SYMBOL_GPL(rfkill_set_default); + /* * Rfkill module initialization/deinitialization. */ @@ -723,8 +826,8 @@ 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) { -- 2.30.2