I got this working! Basically I did not realize that SYSFS was more sophisticated than / proc and actually supported file permissions.
This is basically what I did to access a GPIO from Java land. echo "128" >/sys/class/gpio/export echo "out" > /sys/devices/virtual/gpio/gpio128/direction chmod 0666 /sys/devices/virtual/gpio/gpio128/value Now you have GPIO #128 exported in sysfs, configured as an output and accessible to your Java application. Anything else that is accessible via sysfs can be handled in a similar way. NOTE: It has been pointed out to me that this is a security hole. On the other hand, it get things working directly from Java. (the easy way) Enjoy! On Dec 29, 1:58 pm, Deva R <[email protected]> wrote: > >Do I need to use the NDK for this job? > > I guess so. You need a JNI, and can access sysfs from java via the jni > interface. Jave => JNI native => sysfs files > > exact same discussion for another sysfs handling > =>http://groups.google.com/group/android-porting/browse_thread/thread/3... > > > > > > > > > > On Tue, Dec 28, 2010 at 11:36 PM, A Curtis <[email protected]> wrote: > > Hello, > > > I have exported some GPIOs to sysfs and now I want to manipulate them > > from Java. > > > How do I do this? > > > new FileOutputStream("/sys/devices/virtual/gpio/gpio128/value"); // > > throws an error > > > Do I need to use the NDK for this job? > > > TIA > > > -- > > unsubscribe: > > [email protected]<android-porting%2Bunsubscribe@ > > googlegroups.com> > > website:http://groups.google.com/group/android-porting > > -- > Regards, > Devawww.bittoggler.com -- unsubscribe: [email protected] website: http://groups.google.com/group/android-porting
