During the week-end we read the first chapters of LLD3 which very instructive. Our kernel was cross-compiled on Pierre’s laptop so we can’t compile our modules on the Gumstix, we need to cross-compile them as well.
We copied the linaro kernel source tree on his laptop and compiled an hello world module, and it worked! We installed it on the Gumstix and it was alright. Tomorrow we will start making modules playing with the GPIO, SPI and interruptions !