RIOT-OS/RIOT — pull request #1484 by haukepetersen (2014-07-28 16:08:38+00:00)
Title: drivers: improved IF for low-level GPIO driver

Improved the GPIO interface and adjusted existing implementations to it.

Tested for
- stm32f0discovery
- stm32f4discovery

Not (much) tested for `arduino-due`, as proper implementation for it will follow later tonight in a separate PR.