Android GPIO操作

public class GPIOUtil {
    //读GPIO
    private String getGpioString(String path) {
        String defString = "0";// 默认值
        try {
            @SuppressWarnings("resource")
            BufferedReader reader = new BufferedReader(new FileReader(path));
            defString = reader.readLine();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return defString;
    }


    //将GPIO口设置为输出的时候,默认是输出，调用下面的方法即可变成默认输入
    public boolean gpio_input0(View v) {
        return  RootCommand("echo  2 > /sys/class/backlight/rk28_bl/gpio0");
    }
    public boolean gpio_input1(View v) {
        return  RootCommand("echo  2 > /sys/class/backlight/rk28_bl/gpio1");
    }
    public boolean gpio_input2(View v) {
        return RootCommand("echo  2 > /sys/class/backlight/rk28_bl/gpio2");
    }

    //当GPIO口为输出的时候，通过以下的办法来控制高低电平
    public boolean set_gpio0_high(View v) {   //拉高
        boolean FLAG = RootCommand("echo  1 > /sys/class/backlight/rk28_bl/gpio1");
        Log.e("123high", String.valueOf(FLAG));
        return FLAG;
    }

    public boolean set_gpio0_low(View v) {    //拉低
        boolean FLAG =  RootCommand("echo 0 > /sys/class/backlight/rk28_bl/gpio1");
        Log.e("123low", String.valueOf(FLAG));
//        read_gpio0();
        return FLAG;
    }
    //  其他的GPIO口都是一样的方法（gpio0、gpio1、gpio2、gpio3）
    //下面的是执行的方法
    private boolean RootCommand(String command) {
        Process process = null;
        DataOutputStream os = null;
        try {
            process = Runtime.getRuntime().exec("su");
            os = new DataOutputStream(process.getOutputStream());
            os.writeBytes(command + "\n");
            os.writeBytes("exit\n");
            os.flush();
            process.waitFor();
        } catch (Exception e) {
            return false;
        } finally {
            try {
                if (os != null) {
                    os.close();
                }
                process.destroy();
            } catch (Exception e) {
            }
        }
        return true;
    }
}