Zusammenfassung
The talk provides an introduction to the new 'input core' in 2.5 Linux kernels, its implementation and the ramifications for userspace applications using it.
In the current state of affairs, input devices (also called human input devices, or HID for short - keyboards, mice, joysticks, digitizers, and many others) don't share a common API and applications need to implement drivers for them if they want to access them. Thus we have support for many different mouse types in GPM, svgalib, XFree and many non-X based graphic toolkit, as well as many other embedded X implementations. Each architecture (i386 / m68k / ppc /sun / mips ...) has a different set of keycodes and thus we have different keymaps for each, where we could have one for each language only.
The 'input core' in 2.5 implements a simple yet extensible driver stack and interface to the userspace that solves these problems. In 2.5 all keyboards on all architectures will use subsets of the same set of keycodes, applications will need to know only one protocol to talk to mice on any Linux system, etc. The 2.5 'input core' also supports hotplug and thus applications using it must be hotplug-aware.
While the 'input core' work is still in development, it is in a working state and available with any 2.5 kernel. It is also in 2.4 'stable' series, but with a very limited set of capabilities. Now application support is needed - and that mostly means good XFree support of the new input device architecture, that would allow autoconfiguration and hotplug support, two features the input device support in XFree is chronically missing.
Über den Autor
Vojtech Pavlik studied biophysics at the Faculty of Math and Physics of the Charles University. He is now working for SuSE as a member of SuSE Labs (SuSE's R&D department), doing Linux kernel development and a port of the kernel to the AMD x86-64 architecture. He has been involved in Linux kernel development since 1997. One of his main projects in the Linux kernel is a new input layer, abstracting input devices (keyboards, mice, joysticks, tablets, etc) into a common API.
In his spare time he is, among other things, a leader of the U.C.W./Sirael Czech robotics team preparing for the Eurobot 2003 robotic competition in la Ferte Bernard, France.
