ashamed to admit, i haven't been keeping up with this, so AIUI, the GPIO sysfs interface is deprecated, replaced with character device files (/dev/gpiochip*) to allow access to GPIO. first, i find it curious that this is a move away from sysfs access to using ioctl(), since i had always thought ioctls were massively discouraged in new code. is there a document that goes through the rationale for this change? and i notice under Documentation/ABI/ that sysfs-gpio is listed under "obsolete", while gpio-cdev is listed under "testing". this seems inconsistent -- how can one be obsolete while the other be categorized as testing? that just seems strange. in any event, is the /dev/gpiochip* interface the recommended interface now? thanks. rday -- ======================================================================== Robert P. J. Day Ottawa, Ontario, CANADA http://crashcourse.ca Twitter: http://twitter.com/rpjday LinkedIn: http://ca.linkedin.com/in/rpjday ========================================================================