Comedi provides a common Linux interface to certain DAQ hardware,
typical PCI digital and analog I/O cards and is actively developed since 1999.

It consists of

• Linux drivers
• Comedilib
• Kcomedilib

Comedi and available drivers are integrated into the Linux kernel.
For some reasons Comedi is still located in the staging tree.

To enable Comedi and build the comedi module, setup the
kernel configuration as follows:

Device Drivers [*]
    Staging drivers [*]
        Data acquisition support <M>
      

This ensures the built of the comedi module only.
To actually make use of the supported hardware,
the comedi driver(s) need to be set to build.

Taking the ADDI-DATA I/O PCI card 1648 for example,
activate the Comedi PCI drivers section and set the appropriate driver.

            Comedi PCI drivers [*]
                ADDI-DATA APCI_16xx support <M>

This will built the driver module addi_apci_16xx,
which depends on the comedi module.

When loaded, lsmod shows something like:

comedi                 46649  1 addi_apci_16xx

Every device gets a separate comedi[0-9]+ node in the device tree.
Assuming only one card in this example

crw-rw---- 1 root root 98, 0 Aug  4  2015 /dev/comedi0 

ADDI-DATA I/O and Analog