[PATCH synaptics v2 2/2] The correct maximum values for pressure and finger width

[Alexandr Shadchin]

On Fri, Aug 26, 2011 at 03:02:46PM +0200, walter harms wrote:
> 
> 
> Am 26.08.2011 14:42, schrieb Alexandr Shadchin:
> > Signed-off-by: Alexandr Shadchin <Alexandr.Shadchin at gmail.com>
> > ---
> > 
> > Fix evaluation range in set_default_parameters() (suggestion Chris Bagwell)
> > 
> >  src/synaptics.c |    8 ++++----
> >  1 files changed, 4 insertions(+), 4 deletions(-)
> > 
> > diff --git a/src/synaptics.c b/src/synaptics.c
> > index c043b5d..cbdd74d 100644
> > --- a/src/synaptics.c
> > +++ b/src/synaptics.c
> > @@ -246,7 +246,7 @@ SanitizeDimensions(InputInfoPtr pInfo)
> >      if (priv->minp >= priv->maxp)
> >      {
> >  	priv->minp = 0;
> > -	priv->maxp = 256;
> > +	priv->maxp = 255;
> >  
> >  	xf86IDrvMsg(pInfo, X_PROBED,
> >  		    "invalid pressure range.  defaulting to %d - %d\n",
> > @@ -256,7 +256,7 @@ SanitizeDimensions(InputInfoPtr pInfo)
> >      if (priv->minw >= priv->maxw)
> >      {
> >  	priv->minw = 0;
> > -	priv->maxw = 16;
> > +	priv->maxw = 15;
> >  
> >  	xf86IDrvMsg(pInfo, X_PROBED,
> >  		    "invalid finger width range.  defaulting to %d - %d\n",
> > @@ -459,7 +459,7 @@ static void set_default_parameters(InputInfoPtr pInfo)
> >      horizHyst = pars->hyst_x >= 0 ? pars->hyst_x : diag * 0.005;
> >      vertHyst = pars->hyst_y >= 0 ? pars->hyst_y : diag * 0.005;
> >  
> > -    range = priv->maxp - priv->minp;
> > +    range = priv->maxp - priv->minp + 1;
> >  
> >      /* scaling based on defaults and a pressure of 256 */
> >      fingerLow = priv->minp + range * (25.0/256);
> > @@ -472,7 +472,7 @@ static void set_default_parameters(InputInfoPtr pInfo)
> >      pressureMotionMaxZ = priv->minp + range * (160.0/256);
> >      palmMinZ = priv->minp + range * (200.0/256);
> >  
> > -    range = priv->maxw - priv->minw;
> > +    range = priv->maxw - priv->minw + 1;
> >  
> >      /* scaling based on defaults below and a tool width of 16 */
> >      palmMinWidth = priv->minw + range * (10.0/16);
> 
> 
> Could you give a comment why the limit is 15 (or 255) ?
> (i assume 8bit/ 4bit bit i do not know)
> 
> re,
>  wh

In principle, you think right.

more precisely pages 25-26 in Synaptics PS/2 TouchPad Interfacing Guide
(http://www.synaptics.com/developers/manuals)

-- 
Alexandr Shadchin