summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--drivers/leds/Kconfig8
-rw-r--r--drivers/leds/Makefile1
-rw-r--r--drivers/leds/led-class.c20
-rw-r--r--drivers/leds/led-triggers.c239
-rw-r--r--drivers/leds/leds.h13
-rw-r--r--include/linux/leds.h52
6 files changed, 333 insertions, 0 deletions
diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index 106f9aeca04..a4d12ecaf6a 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -14,5 +14,13 @@ config LEDS_CLASS
This option enables the led sysfs class in /sys/class/leds. You'll
need this to do anything useful with LEDs. If unsure, say N.
+config LEDS_TRIGGERS
+ bool "LED Trigger support"
+ depends NEW_LEDS
+ help
+ This option enables trigger support for the leds class.
+ These triggers allow kernel events to drive the LEDs and can
+ be configured via sysfs. If unsure, say Y.
+
endmenu
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index 8a62871437f..a9d8becd618 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -2,3 +2,4 @@
# LED Core
obj-$(CONFIG_NEW_LEDS) += led-core.o
obj-$(CONFIG_LEDS_CLASS) += led-class.o
+obj-$(CONFIG_LEDS_TRIGGERS) += led-triggers.o
diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c
index 0292df4101b..b0b5d05fadd 100644
--- a/drivers/leds/led-class.c
+++ b/drivers/leds/led-class.c
@@ -54,6 +54,9 @@ static ssize_t led_brightness_store(struct class_device *dev,
static CLASS_DEVICE_ATTR(brightness, 0644, led_brightness_show,
led_brightness_store);
+#ifdef CONFIG_LEDS_TRIGGERS
+static CLASS_DEVICE_ATTR(trigger, 0644, led_trigger_show, led_trigger_store);
+#endif
/**
* led_classdev_suspend - suspend an led_classdev.
@@ -100,6 +103,15 @@ int led_classdev_register(struct device *parent, struct led_classdev *led_cdev)
list_add_tail(&led_cdev->node, &leds_list);
write_unlock(&leds_list_lock);
+#ifdef CONFIG_LEDS_TRIGGERS
+ rwlock_init(&led_cdev->trigger_lock);
+
+ led_trigger_set_default(led_cdev);
+
+ class_device_create_file(led_cdev->class_dev,
+ &class_device_attr_trigger);
+#endif
+
printk(KERN_INFO "Registered led device: %s\n",
led_cdev->class_dev->class_id);
@@ -117,6 +129,14 @@ void led_classdev_unregister(struct led_classdev *led_cdev)
{
class_device_remove_file(led_cdev->class_dev,
&class_device_attr_brightness);
+#ifdef CONFIG_LEDS_TRIGGERS
+ class_device_remove_file(led_cdev->class_dev,
+ &class_device_attr_trigger);
+ write_lock(&led_cdev->trigger_lock);
+ if (led_cdev->trigger)
+ led_trigger_set(led_cdev, NULL);
+ write_unlock(&led_cdev->trigger_lock);
+#endif
class_device_unregister(led_cdev->class_dev);
diff --git a/drivers/leds/led-triggers.c b/drivers/leds/led-triggers.c
new file mode 100644
index 00000000000..5e2cd8be119
--- /dev/null
+++ b/drivers/leds/led-triggers.c
@@ -0,0 +1,239 @@
+/*
+ * 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");
diff --git a/drivers/leds/leds.h b/drivers/leds/leds.h
index d26ca2f7e72..a715c4ed93f 100644
--- a/drivers/leds/leds.h
+++ b/drivers/leds/leds.h
@@ -28,4 +28,17 @@ static inline void led_set_brightness(struct led_classdev *led_cdev,
extern rwlock_t leds_list_lock;
extern struct list_head leds_list;
+#ifdef CONFIG_LEDS_TRIGGERS
+void led_trigger_set_default(struct led_classdev *led_cdev);
+void led_trigger_set(struct led_classdev *led_cdev,
+ struct led_trigger *trigger);
+#else
+#define led_trigger_set_default(x) do {} while(0)
+#define led_trigger_set(x, y) do {} while(0)
+#endif
+
+ssize_t led_trigger_store(struct class_device *dev, const char *buf,
+ size_t count);
+ssize_t led_trigger_show(struct class_device *dev, char *buf);
+
#endif /* __LEDS_H_INCLUDED */
diff --git a/include/linux/leds.h b/include/linux/leds.h
index 6812640b39c..404575c3dd5 100644
--- a/include/linux/leds.h
+++ b/include/linux/leds.h
@@ -40,6 +40,14 @@ struct led_classdev {
/* Trigger data */
char *default_trigger;
+#ifdef CONFIG_LEDS_TRIGGERS
+ rwlock_t trigger_lock;
+ /* Protects the trigger data below */
+
+ struct led_trigger *trigger;
+ struct list_head trig_list;
+ void *trigger_data;
+#endif
};
extern int led_classdev_register(struct device *parent,
@@ -48,4 +56,48 @@ extern void led_classdev_unregister(struct led_classdev *led_cdev);
extern void led_classdev_suspend(struct led_classdev *led_cdev);
extern void led_classdev_resume(struct led_classdev *led_cdev);
+/*
+ * LED Triggers
+ */
+#ifdef CONFIG_LEDS_TRIGGERS
+
+#define TRIG_NAME_MAX 50
+
+struct led_trigger {
+ /* Trigger Properties */
+ const char *name;
+ void (*activate)(struct led_classdev *led_cdev);
+ void (*deactivate)(struct led_classdev *led_cdev);
+
+ /* LEDs under control by this trigger (for simple triggers) */
+ rwlock_t leddev_list_lock;
+ struct list_head led_cdevs;
+
+ /* Link to next registered trigger */
+ struct list_head next_trig;
+};
+
+/* Registration functions for complex triggers */
+extern int led_trigger_register(struct led_trigger *trigger);
+extern void led_trigger_unregister(struct led_trigger *trigger);
+
+/* Registration functions for simple triggers */
+#define DEFINE_LED_TRIGGER(x) static struct led_trigger *x;
+#define DEFINE_LED_TRIGGER_GLOBAL(x) struct led_trigger *x;
+extern void led_trigger_register_simple(const char *name,
+ struct led_trigger **trigger);
+extern void led_trigger_unregister_simple(struct led_trigger *trigger);
+extern void led_trigger_event(struct led_trigger *trigger,
+ enum led_brightness event);
+
+#else
+
+/* Triggers aren't active - null macros */
+#define DEFINE_LED_TRIGGER(x)
+#define DEFINE_LED_TRIGGER_GLOBAL(x)
+#define led_trigger_register_simple(x, y) do {} while(0)
+#define led_trigger_unregister_simple(x) do {} while(0)
+#define led_trigger_event(x, y) do {} while(0)
+
+#endif
#endif /* __LINUX_LEDS_H_INCLUDED */