Re: [PATCH 3/4] pinctrl: remove slew-rate parameter from tz1090

On 25/06/13 14:22, Linus Walleij wrote:

Can't we just try to come up with a patch that nails down the meaning of
slew rate in some meaningful manner then?

So according to:
http://en.wikipedia.org/wiki/Slew_rate
a proper expression for slew rate would be dV/dt i.e.
something like microvolts per microsecond (which then just
becomes volts/second).

What we need to figure out is what range will be applicable within
reasonable doubt for current scenarios and the next few years.

What are your datasheets specifying here, and what would be
a proper measure?

My datasheet says:

0: slow (half frequency)
1: fast

I just got a reply back from a hardware engineer, who said that the
relationship with the actual volts/usec will depend on both the drive
strength and the load on the pad, and that a definite answer probably
requires running a simulation.

Cheers
James