[PATCH 3/3] mmc: mmci: Change vdd_handler to a generic ios_handler

[Sebastian RASMUSSEN]

> I'm guessing it was some feature intended to control e.g. a
> regulator of some kind by routing them off-chip (since mixed-signal
> chips rarely have MMC controllers inside...) and most designers
> already have their own regulator designs so it made no sense
> for anyone to actually implement it that way.

Yup, I think ARM PL180 HW IP developers envisioned that the SD-card
regulator and/or level-shifter would utilize these signals electrically
to configure what voltage to use. As far as I read the old TRM the way 
these bits encoded voltage levels were application-specific so I can't
see that there would be any consensus of how to interpret them either.

> If some vendor would actually start using these bits for the
> intended purpose I guess we could adapt. (The pirate driver
> msm_sdcc.c does not seem to use these bits either BTW.)

I never did check whether msm_sdcc used those, but it seemed
unimportant at the time since it's not the same driver (yet).
Nice to know that neither driver uses those though.

 / Sebastian