Hi! I'd like to implement fan speed control for Thinkpads. It is documented at http://www.thinkwiki.org/wiki/How_to_control_fan_speed#Hardware_specs and linux also implements this (but with special case for TP 570, 600e/x, 770e, 770x - anyone here with access to one of these?) Implementing a driver for this will be a piece of cake, but I need help with communication to userspace to get started. I guess the way to go is sysctl (?) In acpithinkpad only read only sensor variables are created. How do I create r/w variables - where can I find code examples? And where in the sysctl tree should I put them?
When I have this working I want to implement a PID controler for it. Since I'd like to see this get committed, where would be the preferred place to put the PID-controller? Kernel or userland? Christopher
