Brother HL-2140
The Brother HL-2140 is a greyscale laser printer. It is compatible with CUPS on Arch Linux, using the hplip driver collection.
Install packages
Install cups and hplip. If you have previously installed printing-related packages, you may want to remove them and any other configurations or modifications you've applied.
Download PPD
Download the necessary PPD from OpenPrinting's HL-2140 page (direct link).