Turn on flash and front camera simultaneously on iPhone

I need to use the front camera and turn on the backlight LED in the iPhone. How should I do it? I can open the front camera with this code:

- (void) turnCameraOn {
if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]) {

    UIImagePickerController *imagePicker = [[UIImagePickerController alloc] init];
    imagePicker.delegate = self;
    imagePicker.sourceType = UIImagePickerControllerSourceTypeCamera;
    imagePicker.cameraDevice = UIImagePickerControllerCameraDeviceFront;
    imagePicker.cameraCaptureMode = UIImagePickerControllerCameraCaptureModePhoto;
    imagePicker.showsCameraControls = YES;

    [self presentViewController:imagePicker animated:YES completion:nil];

} else {

    UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Camera unavaliable"
                                                    message:@"Unable to find camera on your device."
                                                   delegate:nil
                                          cancelButtonTitle:@"OK"
                                          otherButtonTitles:nil, nil];
    [alert show];
    alert = nil;
}
}

      

        
        
        
      

    

and i can turn on the led with this code

- (void) turnTorchOn: (bool) on {
Class captureDeviceClass = NSClassFromString(@"AVCaptureDevice");
if (captureDeviceClass != nil) {
    AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
    if ([device hasTorch] && [device hasFlash]){

        [device lockForConfiguration:nil];

        if (on) {
            [device setTorchMode:AVCaptureTorchModeOn];
            [device setFlashMode:AVCaptureFlashModeOn];
        } else {
            [device setTorchMode:AVCaptureTorchModeOff];
            [device setFlashMode:AVCaptureFlashModeOff];
        }
        [device unlockForConfiguration];
    }
}
}

      

        
        
        
      

    

But when I open APP and the front camera appears, the LED turns off. I need to work at the same time.

thank