Re: [PATCH 03/12] hdaps: Unify and cache hdaps readouts

[Pavel Machek]

Hi!

> >Okay, so what about ..
> >
> >#define CONVERT(x) *(s16*)(data.val+x) * (hdaps_invert?-1:1);
> >
> >...or better inline function?
> 
> Actually, some models require fancier transformations. This was
> supposed to be reserved for a future patch, but might as well prepare
> the infrastructure:

Certainly better.

> /* Some models require an axis transformation to the standard reprsentation 
> */
> static void transform_axes(int inx, int iny, int *outx, int *outy) {
> 	*outx = inx * (hdaps_invert?-1:1);
> 	*outy = iny * (hdaps_invert?-1:1);
> }
> ...
> 	/* Parse position data: */
> 	transform_axes(*(s16*)(data.val+EC_ACCEL_IDX_XPOS1),
> 	               *(s16*)(data.val+EC_ACCEL_IDX_YPOS1), &pos_x, &pos_y);

You could also do

void transform_axes(int *x, int *y)
{
 	*outx = inx * (hdaps_invert?-1:1);
 	*outy = iny * (hdaps_invert?-1:1);
}
...
 	/* Parse position data: */
	x = *(s16*)(data.val+EC_ACCEL_IDX_XPOS1);
	y = *(s16*)(data.val+EC_ACCEL_IDX_YPOS1);
 	transform_axes(&x, &y);

...which looks even better to me.
								Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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