rfkill: add notifier chains support
[safe/jmp/linux-2.6] / net / rfkill / rfkill.c
index f3986d4..a561e35 100644 (file)
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2006 Ivo van Doorn
+ * Copyright (C) 2006 - 2007 Ivo van Doorn
  * Copyright (C) 2007 Dmitry Torokhov
  *
  * This program is free software; you can redistribute it and/or modify
 #include <linux/mutex.h>
 #include <linux/rfkill.h>
 
+/* Get declaration of rfkill_switch_all() to shut up sparse. */
+#include "rfkill-input.h"
+
+
 MODULE_AUTHOR("Ivo van Doorn <IvDoorn@gmail.com>");
 MODULE_VERSION("1.0");
 MODULE_DESCRIPTION("RF switch support");
@@ -35,24 +39,119 @@ MODULE_LICENSE("GPL");
 static LIST_HEAD(rfkill_list); /* list of registered rf switches */
 static DEFINE_MUTEX(rfkill_mutex);
 
+static unsigned int rfkill_default_state = RFKILL_STATE_ON;
+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];
 
+static BLOCKING_NOTIFIER_HEAD(rfkill_notifier_list);
+
+
+/**
+ * register_rfkill_notifier - Add notifier to rfkill notifier chain
+ * @nb: pointer to the new entry to add to the chain
+ *
+ * See blocking_notifier_chain_register() for return value and further
+ * observations.
+ *
+ * Adds a notifier to the rfkill notifier chain.  The chain will be
+ * called with a pointer to the relevant rfkill structure as a parameter,
+ * refer to include/linux/rfkill.h for the possible events.
+ *
+ * Notifiers added to this chain are to always return NOTIFY_DONE.  This
+ * chain is a blocking notifier chain: notifiers can sleep.
+ *
+ * Calls to this chain may have been done through a workqueue.  One must
+ * assume unordered asynchronous behaviour, there is no way to know if
+ * actions related to the event that generated the notification have been
+ * carried out already.
+ */
+int register_rfkill_notifier(struct notifier_block *nb)
+{
+       return blocking_notifier_chain_register(&rfkill_notifier_list, nb);
+}
+EXPORT_SYMBOL_GPL(register_rfkill_notifier);
+
+/**
+ * unregister_rfkill_notifier - remove notifier from rfkill notifier chain
+ * @nb: pointer to the entry to remove from the chain
+ *
+ * See blocking_notifier_chain_unregister() for return value and further
+ * observations.
+ *
+ * Removes a notifier from the rfkill notifier chain.
+ */
+int unregister_rfkill_notifier(struct notifier_block *nb)
+{
+       return blocking_notifier_chain_unregister(&rfkill_notifier_list, nb);
+}
+EXPORT_SYMBOL_GPL(unregister_rfkill_notifier);
+
+
+static void rfkill_led_trigger(struct rfkill *rfkill,
+                              enum rfkill_state state)
+{
+#ifdef CONFIG_RFKILL_LEDS
+       struct led_trigger *led = &rfkill->led_trigger;
+
+       if (!led->name)
+               return;
+       if (state == RFKILL_STATE_OFF)
+               led_trigger_event(led, LED_OFF);
+       else
+               led_trigger_event(led, LED_FULL);
+#endif /* CONFIG_RFKILL_LEDS */
+}
+
+static void notify_rfkill_state_change(struct rfkill *rfkill)
+{
+       blocking_notifier_call_chain(&rfkill_notifier_list,
+                       RFKILL_STATE_CHANGED,
+                       rfkill);
+}
+
+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)
+                               notify_rfkill_state_change(rfkill);
+               }
+               mutex_unlock(&rfkill->mutex);
+       }
+}
+
 static int rfkill_toggle_radio(struct rfkill *rfkill,
-                               enum rfkill_state state)
+                               enum rfkill_state state,
+                               int force)
 {
-       int retval;
+       int retval = 0;
+       enum rfkill_state oldstate, newstate;
 
-       retval = mutex_lock_interruptible(&rfkill->mutex);
-       if (retval)
-               return retval;
+       oldstate = rfkill->state;
 
-       if (state != rfkill->state) {
+       if (rfkill->get_state && !force &&
+           !rfkill->get_state(rfkill->data, &newstate))
+               rfkill->state = newstate;
+
+       if (force || state != rfkill->state) {
                retval = rfkill->toggle_radio(rfkill->data, state);
                if (!retval)
                        rfkill->state = state;
        }
 
-       mutex_unlock(&rfkill->mutex);
+       if (force || rfkill->state != oldstate) {
+               rfkill_led_trigger(rfkill, rfkill->state);
+               notify_rfkill_state_change(rfkill);
+       }
+
        return retval;
 }
 
@@ -65,7 +164,6 @@ static int rfkill_toggle_radio(struct rfkill *rfkill,
  * a specific switch is claimed by userspace in which case it is
  * left alone.
  */
-
 void rfkill_switch_all(enum rfkill_type type, enum rfkill_state state)
 {
        struct rfkill *rfkill;
@@ -75,14 +173,48 @@ void rfkill_switch_all(enum rfkill_type type, enum rfkill_state state)
        rfkill_states[type] = state;
 
        list_for_each_entry(rfkill, &rfkill_list, node) {
-               if (!rfkill->user_claim)
-                       rfkill_toggle_radio(rfkill, state);
+               if ((!rfkill->user_claim) && (rfkill->type == type))
+                       rfkill_toggle_radio(rfkill, state, 0);
        }
 
        mutex_unlock(&rfkill_mutex);
 }
 EXPORT_SYMBOL(rfkill_switch_all);
 
+/**
+ * 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.
+ *
+ * It 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_OFF &&
+           state != RFKILL_STATE_ON)
+               return -EINVAL;
+
+       mutex_lock(&rfkill->mutex);
+
+       oldstate = rfkill->state;
+       rfkill->state = state;
+
+       if (state != oldstate)
+               notify_rfkill_state_change(rfkill);
+
+       mutex_unlock(&rfkill->mutex);
+
+       return 0;
+}
+EXPORT_SYMBOL(rfkill_force_state);
+
 static ssize_t rfkill_name_show(struct device *dev,
                                struct device_attribute *attr,
                                char *buf)
@@ -106,8 +238,14 @@ static ssize_t rfkill_type_show(struct device *dev,
        case RFKILL_TYPE_BLUETOOTH:
                type = "bluetooth";
                break;
-       case RFKILL_TYPE_IRDA:
-               type = "irda";
+       case RFKILL_TYPE_UWB:
+               type = "ultrawideband";
+               break;
+       case RFKILL_TYPE_WIMAX:
+               type = "wimax";
+               break;
+       case RFKILL_TYPE_WWAN:
+               type = "wwan";
                break;
        default:
                BUG();
@@ -122,6 +260,7 @@ static ssize_t rfkill_state_show(struct device *dev,
 {
        struct rfkill *rfkill = to_rfkill(dev);
 
+       update_rfkill_state(rfkill);
        return sprintf(buf, "%d\n", rfkill->state);
 }
 
@@ -136,12 +275,14 @@ static ssize_t rfkill_state_store(struct device *dev,
        if (!capable(CAP_NET_ADMIN))
                return -EPERM;
 
+       if (mutex_lock_interruptible(&rfkill->mutex))
+               return -ERESTARTSYS;
        error = rfkill_toggle_radio(rfkill,
-                       state ? RFKILL_STATE_ON : RFKILL_STATE_OFF);
-       if (error)
-               return error;
+                       state ? RFKILL_STATE_ON : RFKILL_STATE_OFF,
+                       0);
+       mutex_unlock(&rfkill->mutex);
 
-       return count;
+       return error ? error : count;
 }
 
 static ssize_t rfkill_claim_show(struct device *dev,
@@ -172,22 +313,28 @@ static ssize_t rfkill_claim_store(struct device *dev,
        if (error)
                return error;
 
+       if (rfkill->user_claim_unsupported) {
+               error = -EOPNOTSUPP;
+               goto out_unlock;
+       }
        if (rfkill->user_claim != claim) {
                if (!claim)
                        rfkill_toggle_radio(rfkill,
-                                           rfkill_states[rfkill->type]);
+                                           rfkill_states[rfkill->type],
+                                           0);
                rfkill->user_claim = claim;
        }
 
+out_unlock:
        mutex_unlock(&rfkill_mutex);
 
-       return count;
+       return error ? error : count;
 }
 
 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, rfkill_state_show, rfkill_state_store),
+       __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
 };
@@ -206,13 +353,12 @@ 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_SUSPEND) {
-                       mutex_lock(&rfkill->mutex);
-
-                       if (rfkill->state == RFKILL_STATE_ON)
-                               rfkill->toggle_radio(rfkill->data,
-                                                    RFKILL_STATE_OFF);
+               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_OFF);
                        mutex_unlock(&rfkill->mutex);
                }
 
@@ -229,8 +375,8 @@ static int rfkill_resume(struct device *dev)
        if (dev->power.power_state.event != PM_EVENT_ON) {
                mutex_lock(&rfkill->mutex);
 
-               if (rfkill->state == RFKILL_STATE_ON)
-                       rfkill->toggle_radio(rfkill->data, RFKILL_STATE_ON);
+               /* restore radio state AND notify everybody */
+               rfkill_toggle_radio(rfkill, rfkill->state, 1);
 
                mutex_unlock(&rfkill->mutex);
        }
@@ -253,35 +399,31 @@ static struct class rfkill_class = {
 
 static int rfkill_add_switch(struct rfkill *rfkill)
 {
-       int retval;
-
-       retval = mutex_lock_interruptible(&rfkill_mutex);
-       if (retval)
-               return retval;
+       int error;
 
-       retval = rfkill_toggle_radio(rfkill, rfkill_states[rfkill->type]);
-       if (retval)
-               goto out;
+       mutex_lock(&rfkill_mutex);
 
-       list_add_tail(&rfkill->node, &rfkill_list);
+       error = rfkill_toggle_radio(rfkill, rfkill_states[rfkill->type], 0);
+       if (!error)
+               list_add_tail(&rfkill->node, &rfkill_list);
 
- out:
        mutex_unlock(&rfkill_mutex);
-       return retval;
+
+       return error;
 }
 
 static void rfkill_remove_switch(struct rfkill *rfkill)
 {
        mutex_lock(&rfkill_mutex);
        list_del_init(&rfkill->node);
-       rfkill_toggle_radio(rfkill, RFKILL_STATE_OFF);
+       rfkill_toggle_radio(rfkill, RFKILL_STATE_OFF, 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 (wlan, bluetooth, irda)
+ * @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
@@ -318,7 +460,7 @@ 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 destoryed.
+ * Decrements reference count of rfkill structure so it is destroyed.
  * Note that rfkill_free() should _not_ be called after rfkill_unregister().
  */
 void rfkill_free(struct rfkill *rfkill)
@@ -328,6 +470,26 @@ void rfkill_free(struct rfkill *rfkill)
 }
 EXPORT_SYMBOL(rfkill_free);
 
+static void rfkill_led_trigger_register(struct rfkill *rfkill)
+{
+#ifdef CONFIG_RFKILL_LEDS
+       int error;
+
+       rfkill->led_trigger.name = rfkill->dev.bus_id;
+       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);
+#endif
+}
+
 /**
  * rfkill_register - Register a rfkill structure.
  * @rfkill: rfkill structure to be registered
@@ -344,16 +506,23 @@ int rfkill_register(struct rfkill *rfkill)
 
        if (!rfkill->toggle_radio)
                return -EINVAL;
-
-       error = rfkill_add_switch(rfkill);
-       if (error)
-               return error;
+       if (rfkill->type >= RFKILL_TYPE_MAX)
+               return -EINVAL;
 
        snprintf(dev->bus_id, sizeof(dev->bus_id),
                 "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_led_trigger_unregister(rfkill);
                rfkill_remove_switch(rfkill);
                return error;
        }
@@ -363,7 +532,7 @@ int rfkill_register(struct rfkill *rfkill)
 EXPORT_SYMBOL(rfkill_register);
 
 /**
- * rfkill_unregister - Uegister a rfkill structure.
+ * rfkill_unregister - Unregister a rfkill structure.
  * @rfkill: rfkill structure to be unregistered
  *
  * This function should be called by the network driver during device
@@ -374,6 +543,7 @@ void rfkill_unregister(struct rfkill *rfkill)
 {
        device_del(&rfkill->dev);
        rfkill_remove_switch(rfkill);
+       rfkill_led_trigger_unregister(rfkill);
        put_device(&rfkill->dev);
 }
 EXPORT_SYMBOL(rfkill_unregister);
@@ -386,8 +556,12 @@ static int __init rfkill_init(void)
        int error;
        int i;
 
+       if (rfkill_default_state != RFKILL_STATE_OFF &&
+           rfkill_default_state != RFKILL_STATE_ON)
+               return -EINVAL;
+
        for (i = 0; i < ARRAY_SIZE(rfkill_states); i++)
-               rfkill_states[i] = RFKILL_STATE_ON;
+               rfkill_states[i] = rfkill_default_state;
 
        error = class_register(&rfkill_class);
        if (error) {
@@ -403,5 +577,5 @@ static void __exit rfkill_exit(void)
        class_unregister(&rfkill_class);
 }
 
-module_init(rfkill_init);
+subsys_initcall(rfkill_init);
 module_exit(rfkill_exit);