Tizen Native API  9.0
Functions
Led
Device

The Led API provides functions to control the attached led device.

Required Header

#include <device/led.h>

Overview

The Led API provides the way to control the attached LED device such as the camera flash and service LED. It supports to turn on the camera flash and set the pattern to the service LED which is located to the front of a device.

Related Features

This API is related with the following features:

  • http://tizen.org/feature/led
  • http://tizen.org/feature/camera.back.flash

It is recommended to design feature related codes in your application for reliability.

You can check if a device supports the related features for this API by using System Information, thereby controlling the procedure of your application.

To ensure your application is only running on the device with specific features, please define the features in your manifest file using the manifest editor in the SDK.

More details on featuring your application can be found from feature element description.

Functions

int device_flash_get_max_brightness (int *max_brightness)
 Gets the max brightness value of a LED that is located next to the camera.
int device_flash_get_brightness (int *brightness)
 Gets the brightness value of a LED that is located next to the camera.
int device_flash_set_brightness (int brightness)
 Sets the brightness value of a LED that is located next to the camera.
int device_led_play_custom (int on, int off, unsigned int color, unsigned int flags)
 Plays the custom effect of the service LED that is located to the front of a device.
int device_led_stop_custom (void)
 Stops the custom effect of the service LED that is located to the front of a device.

Enumeration Type Documentation

enum led_custom_flags

Enumeration for custom LED flags.

Since :
2.3
Enumerator:
LED_CUSTOM_DUTY_ON 

blink LED

LED_CUSTOM_DEFAULT 

Default flag

Function Documentation

int device_flash_get_brightness ( int *  brightness)

Gets the brightness value of a LED that is located next to the camera.

Retrieves the current brightness level of the back camera flash.
The brightness level is filled in the brightness parameter.

Since :
2.3
Privilege Level:
public
Privilege:
http://tizen.org/privilege/led
Remarks:
This API is related to the following feature: http://tizen.org/feature/camera.back.flash
Parameters:
[out]brightnessThe brightness value of LED (0 ~ MAX)
Returns:
0 on success, otherwise a negative error value
Return values:
DEVICE_ERROR_NONESuccessful
DEVICE_ERROR_INVALID_PARAMETERInvalid parameter
DEVICE_ERROR_PERMISSION_DENIEDPermission denied
DEVICE_ERROR_OPERATION_FAILEDOperation failed
DEVICE_ERROR_NOT_SUPPORTEDNot supported device 
 #include <device/led.h>
 ...
 int brightness = 0;
 int ret = 0;
 ...
 ret = device_flash_get_brightness(&brightness);
 ...
See also:
device_flash_set_brightness()
int device_flash_get_max_brightness ( int *  max_brightness)

Gets the max brightness value of a LED that is located next to the camera.

Retrieves the maximum brightness level of the back camera flash.

Since :
2.3
Privilege Level:
public
Privilege:
http://tizen.org/privilege/led
Remarks:
This API is related to the following feature: http://tizen.org/feature/camera.back.flash
Parameters:
[out]max_brightnessThe max brightness value of the LED
Returns:
0 on success, otherwise a negative error value
Return values:
DEVICE_ERROR_NONESuccessful
DEVICE_ERROR_INVALID_PARAMETERInvalid parameter
DEVICE_ERROR_PERMISSION_DENIEDPermission denied
DEVICE_ERROR_OPERATION_FAILEDOperation failed
DEVICE_ERROR_NOT_SUPPORTEDNot supported device 
 #include <device/led.h>
 ...
 int max_brightness = 0;
 int ret = 0;
 ...
 ret = device_flash_get_max_brightness(&max_brightness);
 ...
int device_flash_set_brightness ( int  brightness)

Sets the brightness value of a LED that is located next to the camera.

Sets the brightness level of the back camera flash.
The desired brightness level is specified in the brightness parameter.

Since :
2.3
Privilege Level:
public
Privilege:
http://tizen.org/privilege/led
Remarks:
Since 2.4, this API check camera flash status whether camera API preempted flash or not, so it could be failed if flash was preempted by camera API. In this case, API will return DEVICE_ERROR_RESOURCE_BUSY error. This API is related to the following feature: http://tizen.org/feature/camera.back.flash
Parameters:
[in]brightnessThe brightness value of LED (0 ~ MAX)
Returns:
0 on success, otherwise a negative error value
Return values:
DEVICE_ERROR_NONESuccessful
DEVICE_ERROR_INVALID_PARAMETERInvalid parameter
DEVICE_ERROR_PERMISSION_DENIEDPermission denied
DEVICE_ERROR_OPERATION_FAILEDOperation failed
DEVICE_ERROR_NOT_SUPPORTEDNot supported device
DEVICE_ERROR_RESOURCE_BUSYDevice or resource busy 
 #include <device/led.h>
 ...
 int brightness = 0;
 int ret = 0;
 ...
 ret = device_flash_set_brightness(brightness);
 ...
See also:
device_flash_get_max_brightness()
device_flash_get_brightness()
int device_led_play_custom ( int  on,
int  off,
unsigned int  color,
unsigned int  flags 
)

Plays the custom effect of the service LED that is located to the front of a device.

Since :
2.3
Privilege Level:
public
Privilege:
http://tizen.org/privilege/led
Remarks:
This API is related to the following feature: http://tizen.org/feature/led
Parameters:
[in]onTurn on time in milliseconds
[in]offTurn off time in milliseconds
[in]colorThe Color value
The first byte means opaque and the other 3 bytes are RGB values
[in]flagsThe combination of enum led_custom_flags
Returns:
0 on success, otherwise a negative error value
Return values:
DEVICE_ERROR_NONESuccessful
DEVICE_ERROR_INVALID_PARAMETERInvalid parameter
DEVICE_ERROR_PERMISSION_DENIEDPermission denied
DEVICE_ERROR_OPERATION_FAILEDOperation failed
DEVICE_ERROR_NOT_SUPPORTEDNot supported device 
 #include <stdio.h>
 #include <device/led.h>
 ...
 int on_time = 100; // On time in milliseconds
 int off_time = 200; // Off time in milliseconds
 unsigned int color = 0xFF0000; // Red color with full opacity
 unsigned int flags = LED_CUSTOM_DEFAULT; // Default flag
 int ret = device_led_play_custom(on_time, off_time, color, flags);
 if (ret != DEVICE_ERROR_NONE) {
     ...
     return -1;
 }
 printf("Custom effect played successfully.\n");
 ...
See also:
device_led_stop_custom()
int device_led_stop_custom ( void  )

Stops the custom effect of the service LED that is located to the front of a device.

Stops the custom effect of the service LED located at the front of the device. The custom effect was started by calling device_led_play_custom().

Since :
2.3
Privilege Level:
public
Privilege:
http://tizen.org/privilege/led
Remarks:
This API is related to the following feature: http://tizen.org/feature/led
Requested custom effects by device_led_play_custom() are removed.
Returns:
0 on success, otherwise a negative error value
Return values:
DEVICE_ERROR_NONESuccessful
DEVICE_ERROR_INVALID_PARAMETERInvalid parameter
DEVICE_ERROR_PERMISSION_DENIEDPermission denied
DEVICE_ERROR_OPERATION_FAILEDOperation failed
DEVICE_ERROR_NOT_SUPPORTEDNot supported device 
 #include <device/led.h>
 ...
 int ret = device_led_play_custom(100, 200, 0xFF0000, LED_CUSTOM_DEFAULT);
 if (ret != DEVICE_ERROR_NONE) {
     return -1;
 }
 sleep(5); // Wait for 5 seconds
 ret = device_led_stop_custom();
 ...
See also:
device_led_play_custom()