[U-Boot] [PATCH] Davinci: add a pin multiplexer configuration API

[Thompson, Nick (GE EntSol, Intelligent Platforms)]

From: Kim Phillips [mailto:kim.phillips at freescale.com]
Sent: 30 October 2009 14:57
> On Fri, 30 Oct 2009 09:26:12 +0100
> Wolfgang Denk <wd at denx.de> wrote:
> 
> > Dear Kim Phillips,
> >
> > In message <20091029182304.469c9f7f.kim.phillips at freescale.com> you wrote:
> > > if (field < PIN_MUX_NUM_FIELDS &&
> > >     (value & ~PIN_MUX_FIELD_MASK) == 0) {
> > >
> > > > +			int offset = field * PIN_MUX_FIELD_SIZE;
> > > > +			unsigned int mux = pins[i].mux;
> > > > +			unsigned int mask = PIN_MUX_FIELD_MASK << offset;
> > >
> > > also please just declare everything at the top of the function - same
> > > for value and field declarations above.
> >
> > No! Why should that be needed? It would be just a waste of stack
> > space (except that recent compilers don't care abouyt this anyway),
> > and keeping variables as localized as possible seems to be a good
> > thing to me.
> 
> not when it sacrifices readability.  I'm looking for assignments and
> finding 'unsigned'!  Either put a blank line between the declarations
> and the rest of the code, or declare everything at the top of the
> function, since it does nothing for the compiler (my preference is the
> latter in this case).
> 
> Kim

All three of these declarations could be const, which may or may not
help the compiler, but would be technically correct and document my
intentions better.

This would not be possible if they where moved to the start of the
function or if the declaration and assignments where split up in any
other way.

Nick.