Brussels / 3 & 4 February 2024


Linux Matchmaking: Helping devices and drivers find each other

Devices identify themselves. Drivers probe matched devices for compatibility.

What appears straight forward on the outset, can be quite serpentine on the everyday System-on-Chip: Devices may refuse to self-identify, require interaction to be addressable, or have - possibly circular - dependencies on other devices. Failure to account for this leads to unchaperoned devices, probe deferrals, and if one is very unlucky, runtime issues up to a bricked system.

Ahmad has debugged a fair share of such issues, either during initial hardware bring-up, after kernel updates or when porting Linux drivers to the barebox bootloader. In his talk, he will introduce the Linux driver model with a focus on tracking dependencies and discuss how to debug and address common issues with tools like ftrace, dev_err_probe and fw_devlink.


Photo of Ahmad Fatoum Ahmad Fatoum