How do I get HDD info from a PS3 Hdd to a PC

Well , my sons PS3 packed up and of course he did’nt back up his game data. It looks to me like Sony have a weird file structure/ OS because I can’t access the drive using my USB 2.0 to SATA/IDE combo adapter. I also can not install it in another PS3 as it justs wants to format the disk. I have tried using Windows and Linux. Any HDD specialists out there able to answer the question .
Tommy