[PATCHv9 1/3] Runtime Interpreted Power Sequences

Grant Likely grant.likely at secretlab.ca
Tue Nov 27 02:34:53 EST 2012


On Thu, 22 Nov 2012 22:40:21 +0100, Thierry Reding <thierry.reding at avionic-design.de> wrote:
> On Thu, Nov 22, 2012 at 01:39:41PM +0000, Grant Likely wrote:
> [...]
> > I do think that each sequence should be contained within a single
> > property, but I'm open to other suggestions.
> 
> IIRC a very early prototype did implement something like that. However
> because of the resource issues this had to be string based, so that the
> sequences looked somewhat like (Alex, correct me if I'm wrong):
> 
> 	power-on = <"REGULATOR", "power", 1, "GPIO", "enable", 1>;
> 
> Instead we could possibly have something like:
> 
> 	power-on = <0 &reg 1,
> 		    1 &gpio 42 0 1>;

Yes, that would work, although I still think it would be a good idea to
split the used resources off into the gpios/pwms/regs/etc properties.

> Where the first cell in each entry defines the type (0 = regulator, 1 =
> GPIO) and the rest would be a regular OF specifier for the given type of
> resource along with some defined parameter such as enable/disable,
> voltage, delay in ms, ... I don't know if that sounds any better. It
> looks sort of cryptic but it is more "in the spirit of" DT, right Grant?

It is still kind of a ham-handed approach, but it does fit better with
existing conventions than the hierarchy of nodes does.

g.


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