Template:FAQ/Questions/SD SDIO

Does the gumstix Linux kernel contain an SDIO stack (MMC controller and core driver)?
No it doesn't. It contains an SD stack, but does not do SDIO. The PXA255 CPU supports SDIO, but the spec is completely closed, so there's no way to actually implement it in open-source software.

In theory, our hardware supports SDIO operation but it has never been tested by us, because we are not privy to the magic secrets of SDIO.