From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Andr=C3=A9=20Fabian=20Silva=20Delgado?= Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- drivers/leds/led-class.c | 402 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 402 insertions(+) create mode 100644 drivers/leds/led-class.c (limited to 'drivers/leds/led-class.c') diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c new file mode 100644 index 000000000..7fb2a19ac --- /dev/null +++ b/drivers/leds/led-class.c @@ -0,0 +1,402 @@ +/* + * LED Class Core + * + * Copyright (C) 2005 John Lenz + * Copyright (C) 2005-2007 Richard Purdie + * + * 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 +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "leds.h" + +static struct class *leds_class; + +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; + + mutex_lock(&led_cdev->led_access); + + if (led_sysfs_is_disabled(led_cdev)) { + ret = -EBUSY; + goto unlock; + } + + ret = kstrtoul(buf, 10, &state); + if (ret) + goto unlock; + + if (state == LED_OFF) + led_trigger_remove(led_cdev); + led_set_brightness(led_cdev, state); + + ret = size; +unlock: + mutex_unlock(&led_cdev->led_access); + return ret; +} +static DEVICE_ATTR_RW(brightness); + +static ssize_t 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_RO(max_brightness); + +#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_async(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_async(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_async(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); + + if (led_cdev->flash_resume) + led_cdev->flash_resume(led_cdev); + + led_cdev->flags &= ~LED_SUSPENDED; +} +EXPORT_SYMBOL_GPL(led_classdev_resume); + +#ifdef CONFIG_PM_SLEEP +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; +} +#endif + +static SIMPLE_DEV_PM_OPS(leds_class_dev_pm_ops, led_suspend, led_resume); + +static int match_name(struct device *dev, const void *data) +{ + if (!dev_name(dev)) + return 0; + return !strcmp(dev_name(dev), (char *)data); +} + +static int led_classdev_next_name(const char *init_name, char *name, + size_t len) +{ + unsigned int i = 0; + int ret = 0; + + strlcpy(name, init_name, len); + + while (class_find_device(leds_class, NULL, name, match_name) && + (ret < len)) + ret = snprintf(name, len, "%s_%u", init_name, ++i); + + if (ret >= len) + return -ENOMEM; + + return i; +} + +/** + * 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) +{ + char name[64]; + int ret; + + ret = led_classdev_next_name(led_cdev->name, name, sizeof(name)); + if (ret < 0) + return ret; + + led_cdev->dev = device_create_with_groups(leds_class, parent, 0, + led_cdev, led_cdev->groups, "%s", name); + if (IS_ERR(led_cdev->dev)) + return PTR_ERR(led_cdev->dev); + + if (ret) + dev_warn(parent, "Led %s renamed to %s due to name collision", + led_cdev->name, dev_name(led_cdev->dev)); + +#ifdef CONFIG_LEDS_TRIGGERS + init_rwsem(&led_cdev->trigger_lock); +#endif + mutex_init(&led_cdev->led_access); + /* 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_cdev->flags |= SET_BRIGHTNESS_ASYNC; + + led_update_brightness(led_cdev); + + INIT_WORK(&led_cdev->set_brightness_work, set_brightness_delayed); + + setup_timer(&led_cdev->blink_timer, led_timer_function, + (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); + + mutex_destroy(&led_cdev->led_access); +} +EXPORT_SYMBOL_GPL(led_classdev_unregister); + +static void devm_led_classdev_release(struct device *dev, void *res) +{ + led_classdev_unregister(*(struct led_classdev **)res); +} + +/** + * devm_led_classdev_register - resource managed led_classdev_register() + * @parent: The device to register. + * @led_cdev: the led_classdev structure for this device. + */ +int devm_led_classdev_register(struct device *parent, + struct led_classdev *led_cdev) +{ + struct led_classdev **dr; + int rc; + + dr = devres_alloc(devm_led_classdev_release, sizeof(*dr), GFP_KERNEL); + if (!dr) + return -ENOMEM; + + rc = led_classdev_register(parent, led_cdev); + if (rc) { + devres_free(dr); + return rc; + } + + *dr = led_cdev; + devres_add(parent, dr); + + return 0; +} +EXPORT_SYMBOL_GPL(devm_led_classdev_register); + +static int devm_led_classdev_match(struct device *dev, void *res, void *data) +{ + struct led_cdev **p = res; + + if (WARN_ON(!p || !*p)) + return 0; + + return *p == data; +} + +/** + * devm_led_classdev_unregister() - resource managed led_classdev_unregister() + * @parent: The device to unregister. + * @led_cdev: the led_classdev structure for this device. + */ +void devm_led_classdev_unregister(struct device *dev, + struct led_classdev *led_cdev) +{ + WARN_ON(devres_release(dev, + devm_led_classdev_release, + devm_led_classdev_match, led_cdev)); +} +EXPORT_SYMBOL_GPL(devm_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"); -- cgit v1.2.3