pinctrl: group/pin identity mapping
ben at trinity.fluff.org
Fri Jun 1 06:40:10 EDT 2012
On Fri, Jun 01, 2012 at 12:06:47PM +0200, Grégor Boirie wrote:
> Hi All,
> I'm trying to implement pinctrl support for our new cortex based SoC.
> Our driver should provide support for pinctrl/pinmux/pinconf combination
> without device tree handling at the moment.
> However, I'm afraid I misunderstand how groups relate to muxed pins and
> I'd like to hear your suggestions.
> Here's the HW: our I/O pins subsystem allows us to multiplex every
> controllable pins using up to 4 mutually exclusive functions, i.e. there
> is no notion of pin GROUP multiplexing at the HW level (one register per
> pin is available to setup multiplexing and other electronic properties
> like drive strength, pull up/down...).
That sounds very much like how the Samsung system works, you might have
a look at their implementation or get them to give you some feedback on
the approach they took.
I brought this to Linus' attention a couple of times when he was designing
the system originally, so he may also have a good idea of what can be done.
Ben Dooks, ben at fluff.org, http://www.fluff.org/ben/
Large Hadron Colada: A large Pina Colada that makes the universe disappear.
More information about the linux-arm-kernel