[directfb-dev] df_input: mouse reported/used as joystick ?

[Denis Oliver Kropp]

Quoting Stefan Lucke:
> Handling this touchscreen as joystick is a combination of driver code
> and directfb code.
> 
> When setting supported mouse keys with:
> set_bit(BTN_MOUSE,psmouse->dev.keybit);
> or
> set_bit(BTN_TOUCH,psmouse->dev.keybit);
> only additional bits are set.
> 
> So in directfb code it is checked with:
> (touchkitPS/2 eGalax Touchscreen) num_rels = 0, num_abs = 2, num_buttons = 3
> 
>      /* Mouse or Touchscreen? */
>      if ((num_rels >= 2 && num_buttons)  ||  (num_abs == 2 && (num_buttons == 1)))
>           info->desc.type |= DIDTF_MOUSE;
>      else if (num_abs && num_buttons) /* Or a Joystick? */
>           info->desc.type |= DIDTF_JOYSTICK;

AFAIK there's no explicit classification in the Linux Input Architecture to
distinguish between mouse/touchscreen and joystick :-(

> When setting key with:
> psmouse->dev.keybit[LONG(BTN_MOUSE)] = BIT(BTN_LEFT);
> it is reported with num_bottons = 1 hand handled as mouse/touchscreen.
> 
> But it should be always handled as touchscreen.
> So I think directfb code has to be changed, as to my opinion button
> counting is wrong. Only buttons up to BTN_JOYSTICK are counted.
> #define BTN_JOYSTICK            0x120
> #define BTN_TOOL_FINGER         0x145
> #define BTN_TOUCH               0x14a
> 
> Attached patch fixes the recognition for me and maps 
> BTN_TOUCH and BTN_TOOL_FINGER to BTN_MOUSE.

Ok, looks like BTN_TOUCH implies that it's a touch screen...

> What would be the right place to specify coordinate translation
> for touchscreen devices ? At the moment I use the following in
> df_input to get correct coordinates:
> 
> static int llx = 1777, lly = 1727, urx = 276, ury = 328;
> static int scale_x(int val)
> {
>     return /*screen_width -*/
>            (screen_width / 8 +
>            (((screen_width * 6) / 8) * (val - llx)) / (urx - llx));
>     return ((val - llx) / (urx - llx)) * ((screen_width * 6) / 8) + screen_width / 8 ;
>     return ((val - llx) / (urx - llx)) * 1536 + 256;
> }
> 
> static int scale_y(int val)
> {
>     return screen_height -
>            (screen_height / 8 +
>            (((screen_height * 6) / 8) * (val - lly)) / (ury - lly));
>     return ((val - lly) / (ury - lly)) * ((screen_height * 6) / 8) + screen_height / 8 ;
>     return ((val - lly) / (ury - lly)) * 1536 + 256;
> }

Generic support for input device calibration and scaling like this is missing.
The input core would be the best place, with an extension to the driver API.

> -     /* Mouse or Touchscreen? */
> -     if ((num_rels >= 2 && num_buttons)  ||  (num_abs == 2 && (num_buttons == 1)))
> +     /* Mouse, Touchscreen or Smartpad ? */
> +     if ((test_bit( EV_KEY, evbit ) &&
> +          (test_bit( BTN_TOUCH, keybit ) || test_bit( BTN_TOOL_FINGER, keybit ))) ||
> +          ((num_rels >= 2 && num_buttons)  ||  (num_abs == 2 && (num_buttons == 1))))
>            info->desc.type |= DIDTF_MOUSE;
>       else if (num_abs && num_buttons) /* Or a Joystick? */
>            info->desc.type |= DIDTF_JOYSTICK;

I'll apply your patch. In the long term the linux_input driver should
be cleaned up or rewritten.

-- 
Best regards,
  Denis Oliver Kropp
 
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