[PATCH 1/1] of: introduce helper to manage boolean

Grant Likely grant.likely at secretlab.ca
Tue Mar 13 15:16:52 EST 2012


On Tue, 13 Mar 2012 04:17:39 +0100, Jean-Christophe PLAGNIOL-VILLARD <plagnioj at jcrosoft.com> wrote:
> On 14:39 Mon 12 Mar     , Scott Wood wrote:
> > On 03/09/2012 10:36 AM, Jean-Christophe PLAGNIOL-VILLARD wrote:
> > >>>> Ugh.  so any value other than 1 returns false?  I think that will surprise
> > >>>> most people.
> > >>>>
> > >>>> I don't like this api or binding.  If it is a bool property, then why isn't
> > >>>> simply testing for the property existance sufficient?
> > >>> no if you want to disable it
> > >>>
> > >>> if a bool is define in the dtsi and want to disable it int the dts
> > >>>
> > >>> if you we can do the the invert
> > >>>
> > >>> if !0 => true
> > >>>
> > >>> is-ok;			=> true
> > >>> is-ok = <val != 0>;	=> true
> > >>> is-ok = <0>;		=> false
> > >>
> > >> This is a failure of the dtc tool, not the binding.  Accepting this binding
> > >> means we have to live with it for a very long time.  It needs to be fixed
> > >> in dtc instead so that properties can be deleted instead of only modified.
> > > I understand your idea but today if you put and value in the property it's true.
> > > 
> > > So is-ok = <0>; is true also which is illogical as in any language a boolean is
> > > true (1) or false (0). When I read the property I will understand false not true
> > 
> > You could say similar things about is-ok = "no" or is-ok = "" or is-ok =
> > "I'd rather you didn't"... it's expected that violating the binding may
> > produce illogical results.
> today is most of the binding people use a number whe the want to be able to
> delete it and it's the same in most of the promgramming language

It isn't yet a big pain point, so there isn't time pressure here.  Fixing the tool
is the better solution, and since the kernel carries a copy of the tool we don't
need to worry about adding a feature that isn't available by the dtc packaged by
a distribution.

Fixing the tool is the correct thing to do.

g.



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