Synaptics patch review request - add option for invert circular scrolling direction

[Chase Douglas]

On 02/05/2012 09:35 PM, Lukáš Karas wrote:
> Synaptics driver generates negative (up) scrolling event with clockwise 
> circular scrolling gesture. This make sense, when you start this gesture 
> on left corner of touchpad. 
> 
> But when you start on right corner and move your finger from top to bottom, 
> continue to left clockwise, then page scrolls top. This should be intuitive inverted 
> in this case.
> 
> My patch add simple option (bool) that invert circular scrolling direction. 
> User can setup his gesture preferences with that option.
> 
> Please, review this patch, I am not sure in start_coasting function.

Hi Lukáš,

I have a feeling we may want inverted scrolling as a higher level
option. It would affect all scrolling, include two touch drag, circular,
and edge scrolling. I make this claim based on the inversion of
scrolling in OS X. We've already had a bug on launchpad.net requesting
this feature.

Instead of adding property for inverting just circular scrolling,
perhaps we should add a generic scrolling inversion property that takes
two boolean arguments: invert vertical scrolling and invert horizontal
scrolling. It would affect all the scrolling behaviors.

What do you think?

(Btw, your patch seems to include hunks that are unrelated to the
changes. Maybe they have some whitespace munging?)

Thanks for the effort so far!

-- Chase