I think this is a general question for Android JB 4.3 which include a new security control, SELinux.
Our project originally was based on imx6 & Android ICS 4.0.3, due to cost concern we downgrade the CPU to imx6 Sololite but upgrade the BSP to Android JB 4.3 w/o choice since it's the only available version for imx6 Sololite. But due to JB 4.3's strict security, our below solution for "system time change & writing GPIO value by APP" which works in ICS 4.0.3 is failed in JB 4.3:
1. Add below into /device/fsl/imx6/etc/init.rc :
chmod 666 /dev/alarm (for system time)
chmod 666 /sys/class/gpio/gpio12/value
2. Implement OnTimeChangedListener for system time update in APP
3. Execute shell command in APP to control the GPIO
Have surveyed and realize maybe JNI is a possibility but we'd like to know if we still can apply the same by adding the "write-in" permission as above mentioned? All suggestions and comments are more than welcome!