1 files changed, 297 insertions, 0 deletions
diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c
new file mode 100644
index 00000000000..f37d63cf726
--- /dev/null
+++ b/drivers/leds/led-class.c
@@ -0,0 +1,297 @@
+/*
+ * LED Class Core
+ *
+ * Copyright (C) 2005 John Lenz <lenz@cs.wisc.edu>
+ * Copyright (C) 2005-2007 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/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/spinlock.h>
+#include <linux/device.h>
+#include <linux/timer.h>
+#include <linux/err.h>
+#include <linux/ctype.h>
+#include <linux/leds.h>
+#include "leds.h"
+
+static struct class *leds_class;
+
+static void led_update_brightness(struct led_classdev *led_cdev)
+{
+	if (led_cdev->brightness_get)
+		led_cdev->brightness = led_cdev->brightness_get(led_cdev);
+}
+
+static ssize_t brightness_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct led_classdev *led_cdev = dev_get_drvdata(dev);
+
+	/* no lock needed for this */
+	led_update_brightness(led_cdev);
+
+	return sprintf(buf, "%u\n", led_cdev->brightness);
+}
+
+static ssize_t brightness_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t size)
+{
+	struct led_classdev *led_cdev = dev_get_drvdata(dev);
+	unsigned long state;
+	ssize_t ret = -EINVAL;
+
+	ret = kstrtoul(buf, 10, &state);
+	if (ret)
+		return ret;
+
+	if (state == LED_OFF)
+		led_trigger_remove(led_cdev);
+	__led_set_brightness(led_cdev, state);
+
+	return size;
+}
+static DEVICE_ATTR_RW(brightness);
+
+static ssize_t led_max_brightness_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct led_classdev *led_cdev = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%u\n", led_cdev->max_brightness);
+}
+static DEVICE_ATTR(max_brightness, 0444, led_max_brightness_show, NULL);
+
+#ifdef CONFIG_LEDS_TRIGGERS
+static DEVICE_ATTR(trigger, 0644, led_trigger_show, led_trigger_store);
+static struct attribute *led_trigger_attrs[] = {
+	&dev_attr_trigger.attr,
+	NULL,
+};
+static const struct attribute_group led_trigger_group = {
+	.attrs = led_trigger_attrs,
+};
+#endif
+
+static struct attribute *led_class_attrs[] = {
+	&dev_attr_brightness.attr,
+	&dev_attr_max_brightness.attr,
+	NULL,
+};
+
+static const struct attribute_group led_group = {
+	.attrs = led_class_attrs,
+};
+
+static const struct attribute_group *led_groups[] = {
+	&led_group,
+#ifdef CONFIG_LEDS_TRIGGERS
+	&led_trigger_group,
+#endif
+	NULL,
+};
+
+static void led_timer_function(unsigned long data)
+{
+	struct led_classdev *led_cdev = (void *)data;
+	unsigned long brightness;
+	unsigned long delay;
+
+	if (!led_cdev->blink_delay_on || !led_cdev->blink_delay_off) {
+		__led_set_brightness(led_cdev, LED_OFF);
+		return;
+	}
+
+	if (led_cdev->flags & LED_BLINK_ONESHOT_STOP) {
+		led_cdev->flags &= ~LED_BLINK_ONESHOT_STOP;
+		return;
+	}
+
+	brightness = led_get_brightness(led_cdev);
+	if (!brightness) {
+		/* Time to switch the LED on. */
+		brightness = led_cdev->blink_brightness;
+		delay = led_cdev->blink_delay_on;
+	} else {
+		/* Store the current brightness value to be able
+		 * to restore it when the delay_off period is over.
+		 */
+		led_cdev->blink_brightness = brightness;
+		brightness = LED_OFF;
+		delay = led_cdev->blink_delay_off;
+	}
+
+	__led_set_brightness(led_cdev, brightness);
+
+	/* Return in next iteration if led is in one-shot mode and we are in
+	 * the final blink state so that the led is toggled each delay_on +
+	 * delay_off milliseconds in worst case.
+	 */
+	if (led_cdev->flags & LED_BLINK_ONESHOT) {
+		if (led_cdev->flags & LED_BLINK_INVERT) {
+			if (brightness)
+				led_cdev->flags |= LED_BLINK_ONESHOT_STOP;
+		} else {
+			if (!brightness)
+				led_cdev->flags |= LED_BLINK_ONESHOT_STOP;
+		}
+	}
+
+	mod_timer(&led_cdev->blink_timer, jiffies + msecs_to_jiffies(delay));
+}
+
+static void set_brightness_delayed(struct work_struct *ws)
+{
+	struct led_classdev *led_cdev =
+		container_of(ws, struct led_classdev, set_brightness_work);
+
+	led_stop_software_blink(led_cdev);
+
+	__led_set_brightness(led_cdev, led_cdev->delayed_set_value);
+}
+
+/**
+ * led_classdev_suspend - suspend an led_classdev.
+ * @led_cdev: the led_classdev to suspend.
+ */
+void led_classdev_suspend(struct led_classdev *led_cdev)
+{
+	led_cdev->flags |= LED_SUSPENDED;
+	led_cdev->brightness_set(led_cdev, 0);
+}
+EXPORT_SYMBOL_GPL(led_classdev_suspend);
+
+/**
+ * led_classdev_resume - resume an led_classdev.
+ * @led_cdev: the led_classdev to resume.
+ */
+void led_classdev_resume(struct led_classdev *led_cdev)
+{
+	led_cdev->brightness_set(led_cdev, led_cdev->brightness);
+	led_cdev->flags &= ~LED_SUSPENDED;
+}
+EXPORT_SYMBOL_GPL(led_classdev_resume);
+
+static int led_suspend(struct device *dev)
+{
+	struct led_classdev *led_cdev = dev_get_drvdata(dev);
+
+	if (led_cdev->flags & LED_CORE_SUSPENDRESUME)
+		led_classdev_suspend(led_cdev);
+
+	return 0;
+}
+
+static int led_resume(struct device *dev)
+{
+	struct led_classdev *led_cdev = dev_get_drvdata(dev);
+
+	if (led_cdev->flags & LED_CORE_SUSPENDRESUME)
+		led_classdev_resume(led_cdev);
+
+	return 0;
+}
+
+static const struct dev_pm_ops leds_class_dev_pm_ops = {
+	.suspend        = led_suspend,
+	.resume         = led_resume,
+};
+
+/**
+ * led_classdev_register - register a new object of led_classdev class.
+ * @parent: The device to register.
+ * @led_cdev: the led_classdev structure for this device.
+ */
+int led_classdev_register(struct device *parent, struct led_classdev *led_cdev)
+{
+	led_cdev->dev = device_create(leds_class, parent, 0, led_cdev,
+				      "%s", led_cdev->name);
+	if (IS_ERR(led_cdev->dev))
+		return PTR_ERR(led_cdev->dev);
+
+#ifdef CONFIG_LEDS_TRIGGERS
+	init_rwsem(&led_cdev->trigger_lock);
+#endif
+	/* add to the list of leds */
+	down_write(&leds_list_lock);
+	list_add_tail(&led_cdev->node, &leds_list);
+	up_write(&leds_list_lock);
+
+	if (!led_cdev->max_brightness)
+		led_cdev->max_brightness = LED_FULL;
+
+	led_update_brightness(led_cdev);
+
+	INIT_WORK(&led_cdev->set_brightness_work, set_brightness_delayed);
+
+	init_timer(&led_cdev->blink_timer);
+	led_cdev->blink_timer.function = led_timer_function;
+	led_cdev->blink_timer.data = (unsigned long)led_cdev;
+
+#ifdef CONFIG_LEDS_TRIGGERS
+	led_trigger_set_default(led_cdev);
+#endif
+
+	dev_dbg(parent, "Registered led device: %s\n",
+			led_cdev->name);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(led_classdev_register);
+
+/**
+ * led_classdev_unregister - unregisters a object of led_properties class.
+ * @led_cdev: the led device to unregister
+ *
+ * Unregisters a previously registered via led_classdev_register object.
+ */
+void led_classdev_unregister(struct led_classdev *led_cdev)
+{
+#ifdef CONFIG_LEDS_TRIGGERS
+	down_write(&led_cdev->trigger_lock);
+	if (led_cdev->trigger)
+		led_trigger_set(led_cdev, NULL);
+	up_write(&led_cdev->trigger_lock);
+#endif
+
+	cancel_work_sync(&led_cdev->set_brightness_work);
+
+	/* Stop blinking */
+	led_stop_software_blink(led_cdev);
+	led_set_brightness(led_cdev, LED_OFF);
+
+	device_unregister(led_cdev->dev);
+
+	down_write(&leds_list_lock);
+	list_del(&led_cdev->node);
+	up_write(&leds_list_lock);
+}
+EXPORT_SYMBOL_GPL(led_classdev_unregister);
+
+static int __init leds_init(void)
+{
+	leds_class = class_create(THIS_MODULE, "leds");
+	if (IS_ERR(leds_class))
+		return PTR_ERR(leds_class);
+	leds_class->pm = &leds_class_dev_pm_ops;
+	leds_class->dev_groups = led_groups;
+	return 0;
+}
+
+static void __exit leds_exit(void)
+{
+	class_destroy(leds_class);
+}
+
+subsys_initcall(leds_init);
+module_exit(leds_exit);
+
+MODULE_AUTHOR("John Lenz, Richard Purdie");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("LED Class Interface");