--- /dev/null
+/*
+ * LED Triggers Core
+ *
+ * Copyright 2005-2006 Openedhand Ltd.
+ *
+ * Author: Richard Purdie <rpurdie@openedhand.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/spinlock.h>
+#include <linux/device.h>
+#include <linux/sysdev.h>
+#include <linux/timer.h>
+#include <linux/leds.h>
+#include "leds.h"
+
+/*
+ * Nests outside led_cdev->trigger_lock
+ */
+static rwlock_t triggers_list_lock = RW_LOCK_UNLOCKED;
+static LIST_HEAD(trigger_list);
+
+ssize_t led_trigger_store(struct class_device *dev, const char *buf,
+ size_t count)
+{
+ struct led_classdev *led_cdev = class_get_devdata(dev);
+ char trigger_name[TRIG_NAME_MAX];
+ struct led_trigger *trig;
+ size_t len;
+
+ trigger_name[sizeof(trigger_name) - 1] = '\0';
+ strncpy(trigger_name, buf, sizeof(trigger_name) - 1);
+ len = strlen(trigger_name);
+
+ if (len && trigger_name[len - 1] == '\n')
+ trigger_name[len - 1] = '\0';
+
+ if (!strcmp(trigger_name, "none")) {
+ write_lock(&led_cdev->trigger_lock);
+ led_trigger_set(led_cdev, NULL);
+ write_unlock(&led_cdev->trigger_lock);
+ return count;
+ }
+
+ read_lock(&triggers_list_lock);
+ list_for_each_entry(trig, &trigger_list, next_trig) {
+ if (!strcmp(trigger_name, trig->name)) {
+ write_lock(&led_cdev->trigger_lock);
+ led_trigger_set(led_cdev, trig);
+ write_unlock(&led_cdev->trigger_lock);
+
+ read_unlock(&triggers_list_lock);
+ return count;
+ }
+ }
+ read_unlock(&triggers_list_lock);
+
+ return -EINVAL;
+}
+
+
+ssize_t led_trigger_show(struct class_device *dev, char *buf)
+{
+ struct led_classdev *led_cdev = class_get_devdata(dev);
+ struct led_trigger *trig;
+ int len = 0;
+
+ read_lock(&triggers_list_lock);
+ read_lock(&led_cdev->trigger_lock);
+
+ if (!led_cdev->trigger)
+ len += sprintf(buf+len, "[none] ");
+ else
+ len += sprintf(buf+len, "none ");
+
+ list_for_each_entry(trig, &trigger_list, next_trig) {
+ if (led_cdev->trigger && !strcmp(led_cdev->trigger->name,
+ trig->name))
+ len += sprintf(buf+len, "[%s] ", trig->name);
+ else
+ len += sprintf(buf+len, "%s ", trig->name);
+ }
+ read_unlock(&led_cdev->trigger_lock);
+ read_unlock(&triggers_list_lock);
+
+ len += sprintf(len+buf, "\n");
+ return len;
+}
+
+void led_trigger_event(struct led_trigger *trigger,
+ enum led_brightness brightness)
+{
+ struct list_head *entry;
+
+ if (!trigger)
+ return;
+
+ read_lock(&trigger->leddev_list_lock);
+ list_for_each(entry, &trigger->led_cdevs) {
+ struct led_classdev *led_cdev;
+
+ led_cdev = list_entry(entry, struct led_classdev, trig_list);
+ led_set_brightness(led_cdev, brightness);
+ }
+ read_unlock(&trigger->leddev_list_lock);
+}
+
+/* Caller must ensure led_cdev->trigger_lock held */
+void led_trigger_set(struct led_classdev *led_cdev, struct led_trigger *trigger)
+{
+ unsigned long flags;
+
+ /* Remove any existing trigger */
+ if (led_cdev->trigger) {
+ write_lock_irqsave(&led_cdev->trigger->leddev_list_lock, flags);
+ list_del(&led_cdev->trig_list);
+ write_unlock_irqrestore(&led_cdev->trigger->leddev_list_lock, flags);
+ if (led_cdev->trigger->deactivate)
+ led_cdev->trigger->deactivate(led_cdev);
+ }
+ if (trigger) {
+ write_lock_irqsave(&trigger->leddev_list_lock, flags);
+ list_add_tail(&led_cdev->trig_list, &trigger->led_cdevs);
+ write_unlock_irqrestore(&trigger->leddev_list_lock, flags);
+ if (trigger->activate)
+ trigger->activate(led_cdev);
+ }
+ led_cdev->trigger = trigger;
+}
+
+void led_trigger_set_default(struct led_classdev *led_cdev)
+{
+ struct led_trigger *trig;
+
+ if (!led_cdev->default_trigger)
+ return;
+
+ read_lock(&triggers_list_lock);
+ write_lock(&led_cdev->trigger_lock);
+ list_for_each_entry(trig, &trigger_list, next_trig) {
+ if (!strcmp(led_cdev->default_trigger, trig->name))
+ led_trigger_set(led_cdev, trig);
+ }
+ write_unlock(&led_cdev->trigger_lock);
+ read_unlock(&triggers_list_lock);
+}
+
+int led_trigger_register(struct led_trigger *trigger)
+{
+ struct led_classdev *led_cdev;
+
+ rwlock_init(&trigger->leddev_list_lock);
+ INIT_LIST_HEAD(&trigger->led_cdevs);
+
+ /* Add to the list of led triggers */
+ write_lock(&triggers_list_lock);
+ list_add_tail(&trigger->next_trig, &trigger_list);
+ write_unlock(&triggers_list_lock);
+
+ /* Register with any LEDs that have this as a default trigger */
+ read_lock(&leds_list_lock);
+ list_for_each_entry(led_cdev, &leds_list, node) {
+ write_lock(&led_cdev->trigger_lock);
+ if (!led_cdev->trigger && led_cdev->default_trigger &&
+ !strcmp(led_cdev->default_trigger, trigger->name))
+ led_trigger_set(led_cdev, trigger);
+ write_unlock(&led_cdev->trigger_lock);
+ }
+ read_unlock(&leds_list_lock);
+
+ return 0;
+}
+
+void led_trigger_register_simple(const char *name, struct led_trigger **tp)
+{
+ struct led_trigger *trigger;
+
+ trigger = kzalloc(sizeof(struct led_trigger), GFP_KERNEL);
+
+ if (trigger) {
+ trigger->name = name;
+ led_trigger_register(trigger);
+ }
+ *tp = trigger;
+}
+
+void led_trigger_unregister(struct led_trigger *trigger)
+{
+ struct led_classdev *led_cdev;
+
+ /* Remove from the list of led triggers */
+ write_lock(&triggers_list_lock);
+ list_del(&trigger->next_trig);
+ write_unlock(&triggers_list_lock);
+
+ /* Remove anyone actively using this trigger */
+ read_lock(&leds_list_lock);
+ list_for_each_entry(led_cdev, &leds_list, node) {
+ write_lock(&led_cdev->trigger_lock);
+ if (led_cdev->trigger == trigger)
+ led_trigger_set(led_cdev, NULL);
+ write_unlock(&led_cdev->trigger_lock);
+ }
+ read_unlock(&leds_list_lock);
+}
+
+void led_trigger_unregister_simple(struct led_trigger *trigger)
+{
+ led_trigger_unregister(trigger);
+ kfree(trigger);
+}
+
+/* Used by LED Class */
+EXPORT_SYMBOL_GPL(led_trigger_set);
+EXPORT_SYMBOL_GPL(led_trigger_set_default);
+EXPORT_SYMBOL_GPL(led_trigger_show);
+EXPORT_SYMBOL_GPL(led_trigger_store);
+
+/* LED Trigger Interface */
+EXPORT_SYMBOL_GPL(led_trigger_register);
+EXPORT_SYMBOL_GPL(led_trigger_unregister);
+
+/* Simple LED Tigger Interface */
+EXPORT_SYMBOL_GPL(led_trigger_register_simple);
+EXPORT_SYMBOL_GPL(led_trigger_unregister_simple);
+EXPORT_SYMBOL_GPL(led_trigger_event);
+
+MODULE_AUTHOR("Richard Purdie");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("LED Triggers Core");
git://git.onelab.eu / linux-2.6.git / blobdiff