Atmega1284P-PU - how to connect more than one device through SPI?
You can use several modules using the same exact pins. The trick is to not let these several devices work at the same time. It is easily done by keeping only one Slave Select (SS) line low. What I mean by that you can have multiple Slave Select lines and control them from your application.

I would also advise using pull-up resistors on these Slave Select lines to avoid interference when writing your program to flash because programmer also uses SPI interface. I've had a problem like that myself some time ago