$ scanimage --list-devices
device `hpaio:/usb/Photosmart_6520_series?serial=TH336110H605XP' is a Hewlett-Packard Photosmart_6520_series all-in-one
device `hpaio:/net/Photosmart_2600_series?zc=HPB469D3' is a Hewlett-Packard Photosmart_2600_series all-in-one