This script can be useful for:
- Figuring out the list of modules you need to pack in initrd
- Figuring out the list of drivers you need to modularize for a device
  to be fully functional without building in any dependencies.
- Figuring out which drivers to enable first, when porting drivers
  between kernels (say, to upstream).
- Plotting graphs of system dependencies, etc.

Usage: dev-needs.sh [-c|-d|-m|-f] [filter options] <list of devices>

This script needs to be run on the target device once it has booted to a
shell.

The script takes as input a list of one or more device directories under
/sys/devices and then lists the probe dependency chain (suppliers and
parents) of these devices. It does a breadth first search of the dependency
chain, so the last entry in the output is close to the root of the
dependency chain.

By default it lists the full path to the devices under /sys/devices.

It also takes an optional modifier flag as the first par...