diff options
Diffstat (limited to 'kernel/drivers/leds/led-core.c')
| -rw-r--r-- | kernel/drivers/leds/led-core.c | 175 |
1 files changed, 175 insertions, 0 deletions
diff --git a/kernel/drivers/leds/led-core.c b/kernel/drivers/leds/led-core.c new file mode 100644 index 000000000..9886dace5 --- /dev/null +++ b/kernel/drivers/leds/led-core.c @@ -0,0 +1,175 @@ +/* + * LED Class 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/kernel.h> +#include <linux/leds.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/rwsem.h> +#include "leds.h" + +DECLARE_RWSEM(leds_list_lock); +EXPORT_SYMBOL_GPL(leds_list_lock); + +LIST_HEAD(leds_list); +EXPORT_SYMBOL_GPL(leds_list); + +static void led_set_software_blink(struct led_classdev *led_cdev, + unsigned long delay_on, + unsigned long delay_off) +{ + int current_brightness; + + current_brightness = led_get_brightness(led_cdev); + if (current_brightness) + led_cdev->blink_brightness = current_brightness; + if (!led_cdev->blink_brightness) + led_cdev->blink_brightness = led_cdev->max_brightness; + + led_cdev->blink_delay_on = delay_on; + led_cdev->blink_delay_off = delay_off; + + /* never on - just set to off */ + if (!delay_on) { + led_set_brightness_async(led_cdev, LED_OFF); + return; + } + + /* never off - just set to brightness */ + if (!delay_off) { + led_set_brightness_async(led_cdev, led_cdev->blink_brightness); + return; + } + + mod_timer(&led_cdev->blink_timer, jiffies + 1); +} + + +static void led_blink_setup(struct led_classdev *led_cdev, + unsigned long *delay_on, + unsigned long *delay_off) +{ + if (!(led_cdev->flags & LED_BLINK_ONESHOT) && + led_cdev->blink_set && + !led_cdev->blink_set(led_cdev, delay_on, delay_off)) + return; + + /* blink with 1 Hz as default if nothing specified */ + if (!*delay_on && !*delay_off) + *delay_on = *delay_off = 500; + + led_set_software_blink(led_cdev, *delay_on, *delay_off); +} + +void led_blink_set(struct led_classdev *led_cdev, + unsigned long *delay_on, + unsigned long *delay_off) +{ + del_timer_sync(&led_cdev->blink_timer); + + led_cdev->flags &= ~LED_BLINK_ONESHOT; + led_cdev->flags &= ~LED_BLINK_ONESHOT_STOP; + + led_blink_setup(led_cdev, delay_on, delay_off); +} +EXPORT_SYMBOL(led_blink_set); + +void led_blink_set_oneshot(struct led_classdev *led_cdev, + unsigned long *delay_on, + unsigned long *delay_off, + int invert) +{ + if ((led_cdev->flags & LED_BLINK_ONESHOT) && + timer_pending(&led_cdev->blink_timer)) + return; + + led_cdev->flags |= LED_BLINK_ONESHOT; + led_cdev->flags &= ~LED_BLINK_ONESHOT_STOP; + + if (invert) + led_cdev->flags |= LED_BLINK_INVERT; + else + led_cdev->flags &= ~LED_BLINK_INVERT; + + led_blink_setup(led_cdev, delay_on, delay_off); +} +EXPORT_SYMBOL(led_blink_set_oneshot); + +void led_stop_software_blink(struct led_classdev *led_cdev) +{ + del_timer_sync(&led_cdev->blink_timer); + led_cdev->blink_delay_on = 0; + led_cdev->blink_delay_off = 0; +} +EXPORT_SYMBOL_GPL(led_stop_software_blink); + +void led_set_brightness(struct led_classdev *led_cdev, + enum led_brightness brightness) +{ + int ret = 0; + + /* delay brightness setting if need to stop soft-blink timer */ + if (led_cdev->blink_delay_on || led_cdev->blink_delay_off) { + led_cdev->delayed_set_value = brightness; + schedule_work(&led_cdev->set_brightness_work); + return; + } + + if (led_cdev->flags & SET_BRIGHTNESS_ASYNC) { + led_set_brightness_async(led_cdev, brightness); + return; + } else if (led_cdev->flags & SET_BRIGHTNESS_SYNC) + ret = led_set_brightness_sync(led_cdev, brightness); + else + ret = -EINVAL; + + if (ret < 0) + dev_dbg(led_cdev->dev, "Setting LED brightness failed (%d)\n", + ret); +} +EXPORT_SYMBOL(led_set_brightness); + +int led_update_brightness(struct led_classdev *led_cdev) +{ + int ret = 0; + + if (led_cdev->brightness_get) { + ret = led_cdev->brightness_get(led_cdev); + if (ret >= 0) { + led_cdev->brightness = ret; + return 0; + } + } + + return ret; +} +EXPORT_SYMBOL(led_update_brightness); + +/* Caller must ensure led_cdev->led_access held */ +void led_sysfs_disable(struct led_classdev *led_cdev) +{ + lockdep_assert_held(&led_cdev->led_access); + + led_cdev->flags |= LED_SYSFS_DISABLE; +} +EXPORT_SYMBOL_GPL(led_sysfs_disable); + +/* Caller must ensure led_cdev->led_access held */ +void led_sysfs_enable(struct led_classdev *led_cdev) +{ + lockdep_assert_held(&led_cdev->led_access); + + led_cdev->flags &= ~LED_SYSFS_DISABLE; +} +EXPORT_SYMBOL_GPL(led_sysfs_enable); |