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

[walter harms]

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