Epson Ink-jets are (IMHO) the first choice for photo printing---AND they are well-supported by Linux. In particular, I have been pleasantly surprised how will the GIMP print system works with may faithful Photo 900 (Little-known cousin to the venerable 1280/1290). Plus GIMP has a plug-in for checking nozzles, cleaning, etc.
I just checked the database on my (not totally current) Ubuntu install, and the R320 and R340 are there. I doubt that you would have any trouble finding a driver.
You can check here: (Gimp-print is now called "Gutenprint)