Android上层访问HAL层（呼吸灯测试代码）

参考：[Android L]SEAndroid开放设备文件结点权限(读或写)方法(涵盖常用操作：sys/xxx、proc/xxx、SystemProperties)

http://blog.csdn.net/yelangjueqi/article/details/46761987

HAL:hardware/nubia_hardware/NX541J/breathlight

核心思想是上层打开/sys/class/leds/nubia_led/路径下文件，写入数据即可调试呼吸灯

alps/device/mediatek/common/sepolicy/file.te

type sysfs_breath_leds, fs_type, sysfs_type;

alps/device/mediatek/common/sepolicy/file_contexts

/sys/class/leds/nubia_led(/.*)?                u:object_r:sysfs_breath_leds:s0

/sys/class/leds/nubia_led/outn         u:object_r:sysfs_breath_leds:s0

/sys/class/leds/nubia_led/grade_parameter              u:object_r:sysfs_breath_leds:s0

/sys/class/leds/nubia_led/fade_parameter               u:object_r:sysfs_breath_leds:s0

/sys/class/leds/nubia_led/blink_mode           u:object_r:sysfs_breath_leds:s0

/sys/devices/soc.4/11008000.i2c/i2c-1/1-0045/leds/nubia_led(/.*)? u:object_r:sysfs_breath_leds:s0

/sys/devices/soc.4/11008000.i2c/i2c-1/1-0045/leds/nubia_led/outn u:object_r:sysfs_breath_leds:s0

/sys/devices/soc.4/11008000.i2c/i2c-1/1-0045/leds/nubia_led/grade_parameter u:object_r:sysfs_breath_leds:s0

/sys/devices/soc.4/11008000.i2c/i2c-1/1-0045/leds/nubia_led/fade_parameter u:object_r:sysfs_breath_leds:s0

/sys/devices/soc.4/11008000.i2c/i2c-1/1-0045/leds/nubia_led/blink_mode u:object_r:sysfs_breath_leds:s0

alps/device/mediatek/common/sepolicy/system_app.te

allow system_app sysfs_breath_leds:dir { search open read write add_name create getattr setattr };

allow system_app sysfs_breath_leds:file { open read write create append unlink ioctl getattr setattr };

allow system_app sysfs_breath_leds:lnk_file { open read write create append unlink ioctl getattr setattr };

allow system_app sysfs_breath_leds:fifo_file { read write open create setattr};

android上层相关代码：

import java.io.File;

import java.io.FileOutputStream;

import java.io.IOException;

//blink_mode

//AW_SW_RESET,         // 0  soft_reset , all regs revert to default value.

//AW_CONST_ON,         // 1 work on a constant lightness.

//AW_CONST_OFF,         // 2 darkness is comming

//AW_AUTO_BREATH,        // 3 self breathing, used in sences such as missing message.

//AW_STEP_FADE_IN,       // 4  fade in means that the lightness is getting stronger.

//AW_STEP_FADE_OUT,     // 5  fade out means that the lightness is getting weaker

//AW_BREATH_ONCE,       // 6 only breath once, touch the home menu for instance.

//AW_RESERVED,         // 7 reserverd. 

    private void turnOnLeds() {  

       //writeFile("blink_mode","0");  

       writeFile("outn","1"); 

       writeFile("grade_parameter","200 255");    

       writeFile("blink_mode","1");    

       

       

       writeFile("outn","0"); 

       //writeFile("grade_parameter","200 255");    

       writeFile("blink_mode","6");    

    }  

//"/sys/class/leds/nubia_led/blink_mode"  

    private void turnOffLeds() {  

       writeFile("blink_mode","0");    

    }  

  

    private void writeFile(String fileName,String writestr){           

       try{  

               FileOutputStream mfile = new FileOutputStream("/sys/class/leds/nubia_led/"+fileName);

    

               byte [] bytes = writestr.getBytes();   

    

               mfile.write(bytes);   

    

               mfile.close();   

       }   

       catch (IOException ex) {  

                Log.w(TAG, "wanglei write File fail: " + ex.toString());

       }   

    }