u-boot/include/led.h
Simon Glass 8f4b612333 dm: led: Add support for getting the state of an LED
It is useful to be able to read the LED as well as write it. Add this to
the uclass and update the GPIO driver.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Ziping Chen <techping.chan@gmail.com>
2017-04-14 19:38:57 -06:00

75 lines
1.5 KiB
C

/*
* Copyright (c) 2015 Google, Inc
* Written by Simon Glass <sjg@chromium.org>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#ifndef __LED_H
#define __LED_H
/**
* struct led_uc_plat - Platform data the uclass stores about each device
*
* @label: LED label
*/
struct led_uc_plat {
const char *label;
};
enum led_state_t {
LEDST_OFF = 0,
LEDST_ON = 1,
LEDST_COUNT,
};
struct led_ops {
/**
* set_state() - set the state of an LED
*
* @dev: LED device to change
* @state: LED state to set
* @return 0 if OK, -ve on error
*/
int (*set_state)(struct udevice *dev, enum led_state_t state);
/**
* led_get_state() - get the state of an LED
*
* @dev: LED device to change
* @return LED state led_state_t, or -ve on error
*/
enum led_state_t (*get_state)(struct udevice *dev);
};
#define led_get_ops(dev) ((struct led_ops *)(dev)->driver->ops)
/**
* led_get_by_label() - Find an LED device by label
*
* @label: LED label to look up
* @devp: Returns the associated device, if found
* @return 0 if found, -ENODEV if not found, other -ve on error
*/
int led_get_by_label(const char *label, struct udevice **devp);
/**
* led_set_state() - set the state of an LED
*
* @dev: LED device to change
* @state: LED state to set
* @return 0 if OK, -ve on error
*/
int led_set_state(struct udevice *dev, enum led_state_t state);
/**
* led_get_state() - get the state of an LED
*
* @dev: LED device to change
* @return LED state led_state_t, or -ve on error
*/
enum led_state_t led_get_state(struct udevice *dev);
#endif