[PATCH] ClickPad support v4

[Peter Hutterer]

On Wed, Dec 08, 2010 at 03:55:47PM +0800, Yan Li wrote:
> This patch adds the support for Synaptics Clickpad devices.
> It requires the change in Linux kernel synaptics input driver, found in
>     https://patchwork.kernel.org/patch/92435/
> The kernel patch is already included in 2.6.34 and later releases.
> 
> When the kernel driver sets only the left-button bit evbit and no
> multi-finger is possible, Clickpad mode is activated.  In this mode,
> the bottom touch area is used as button emulations.  Clicking at the
> bottom-left, bottom-center and bottom-right zone corresponds to a left,
> center and right click.
> 
> v2->v3: Fix the mis-detection of Clickpad device with double-tap feature
>         (e.g. MacBook)
>         Fix one forgotten spacing issue Peter suggested
> 
> v3->v4: Ported to HEAD by Yan Li for MeeGo, also added ClickPad
>         description to man page.
> 
> Signed-off-by: Takashi Iwai <tiwai at suse.de>
> Signed-off-by: Yan Li <yan.i.li at intel.com>
> ---
>  man/synaptics.man  |    8 ++++++
>  src/eventcomm.c    |    7 +++++
>  src/synaptics.c    |   72 +++++++++++++++++++++++++++++++++++++++++++++++++++-
>  src/synapticsstr.h |    2 +
>  4 files changed, 88 insertions(+), 1 deletions(-)
> 
> diff --git a/man/synaptics.man b/man/synaptics.man
> index 3f1ca9d..25f1115 100644
> --- a/man/synaptics.man
> +++ b/man/synaptics.man
> @@ -56,6 +56,14 @@ Pressure dependent motion speed.
>  .IP \(bu 4
>  Run-time configuration using shared memory. This means you can change
>  parameter settings without restarting the X server.
> +.IP \(bu 4
> +Synaptics ClickPad support: ClickPad is a new kind of device from
> +Synaptics that has no visible physical keys. Instead, the whole board
> +is clickable and the device sends out BTN_MIDDLE only. It's the

I take it this should be BTN_LEFT?

> +driver's duty to judge whether the click is a left or right one
> +according to finger location. If the driver detects that the touchpad
> +has only one button, the ClickPad mode will be activated and handles
> +the action correctly.

this hunk needs an explanation on how ClickPad interacts with BottomEdge.

>  .LP
>  Note that depending on the touchpad firmware, some of these features
>  might be available even without using the synaptics driver. Note also
> diff --git a/src/eventcomm.c b/src/eventcomm.c
> index faa66ab..7da5a40 100644
> --- a/src/eventcomm.c
> +++ b/src/eventcomm.c
> @@ -269,6 +269,13 @@ event_query_axis_ranges(LocalDevicePtr local)
>  	}
>  
>  	xf86Msg(X_PROBED, "%s: buttons:%s\n", local->name, buf);
> +
> +	/* clickpad device reports only the single left button mask */
> +	if (priv->has_left && !priv->has_right && !priv->has_middle && !priv->has_double) {
> +		priv->is_clickpad = TRUE;
> +		xf86Msg(X_INFO, "%s: is Clickpad device\n", local->name);
> +	}
> +
>      }
>  }
>  
> diff --git a/src/synaptics.c b/src/synaptics.c
> index 53c3685..2e5f8ae 100644
> --- a/src/synaptics.c
> +++ b/src/synaptics.c
> @@ -506,6 +506,18 @@ static void set_default_parameters(LocalDevicePtr local)
>          vertResolution = priv->resy;
>      }
>  
> +    /* Clickpad mode -- bottom area is used as buttons */
> +    if (priv->is_clickpad) {
> +        int button_bottom;
> +    /* Clickpad devices usually the button area at the bottom, and

there's some word missing, but I can't quite pick which one :)
"position"?

> +     * its size seems ca. 20% of the touchpad height no matter how
> +     * large the pad is.
> +     */
> +    button_bottom = priv->maxy - (abs(priv->maxy - priv->miny) * 20) / 100;
> +    if (button_bottom < b && button_bottom >= t)
> +        b = button_bottom;
> +    }
> +

indendation seems a bit screwed here.
also, abs(...) * 0.2 might be a bit easier to read than "* 20 ) / 100";

>      /* set the parameters */
>      pars->left_edge = xf86SetIntOption(opts, "LeftEdge", l);
>      pars->right_edge = xf86SetIntOption(opts, "RightEdge", r);
> @@ -2153,6 +2165,59 @@ handle_clickfinger(SynapticsParameters *para, struct SynapticsHwState *hw)
>      }
>  }
>  
> +/* clickpad event handling */
> +static void
> +HandleClickpad(LocalDevicePtr local, struct SynapticsHwState *hw, edge_type edge)
> +{
> +    SynapticsPrivate *priv = (SynapticsPrivate *) (local->private);
> +    SynapticsParameters *para = &priv->synpara;
> +

this hunk has bad indentation too

> +    if (edge & BOTTOM_EDGE) {
> +   /* button area */
> +   int width = priv->maxx - priv->minx;
> +   int left_button_x, right_button_x;
> +
> +   /* left and right clickpad button ranges;
> +    * the gap between them is interpreted as a middle-button click
> +    */
> +   left_button_x = width * 2 / 5 + priv->minx;
> +   right_button_x = width * 3 / 5 + priv->minx;
> +
> +   /* clickpad reports only one button, and we need
> +    * to fake left/right buttons depending on the touch position
> +    */
> +   if (hw->left) { /* clicked? */
> +       hw->left = 0;
> +       if (hw->x < left_button_x)
> +       hw->left = 1;
> +       else if (hw->x > right_button_x)
> +       hw->right = 1;
> +       else
> +       hw->middle = 1;
> +   }
> +
> +   /* Don't move pointer position in the button area during clicked,
> +    * except for horiz/vert scrolling is enabled.
> +    *
> +    * The synaptics driver tends to be pretty sensitive.  This hack
> +    * is to avoid that the pointer moves slightly and misses the
> +    * poistion you aimed to click.

typo

> +    *
> +    * Also, when the pointer movement is reported, the dragging
> +    * (with a sort of multi-touching) doesn't work well, too.

I'm not quite sure what you mean here

> +    */
> +   if (hw->left || !(para->scroll_edge_horiz ||
> +             ((edge & RIGHT_EDGE) && para->scroll_edge_vert)))
> +       hw->z = 0; /* don't move pointer */
> +
> +    } else if (hw->left) {
> +   /* dragging */
> +   hw->left = priv->prev_hw.left;
> +   hw->right = priv->prev_hw.right;
> +   hw->middle = priv->prev_hw.middle;
> +    }

I don't see a condition where that else if branch is actually executed.
please double-check this. Did you mean to nest like this?

if (hw->left) {
        if (para .... )
        else {
        /* dragging */
        }
}

> +    priv->prev_hw = *hw;
> +}
>  
>  /* Update the hardware state in shared memory. This is read-only these days,
>   * nothing in the driver reads back from SHM. SHM configuration is a thing of the past.
> @@ -2344,6 +2409,12 @@ HandleState(LocalDevicePtr local, struct SynapticsHwState *hw)
>      if (para->touchpad_off == 1)
>  	return delay;
>  
> +    edge = edge_detection(priv, hw->x, hw->y);

moving this up changes the logic. with the current code, edge is always
NO_EDGE if outside the area. If we move this up, edge is always set and this
may have a result on scrolling. Please check this as well, a cursor check of
the code shows that this could now trigger horizontal scrolling in the
button area.

> +
> +    /* Clickpad handling for button area */
> +    if (priv->is_clickpad)
> +	HandleClickpad(local, hw, edge);
> +
>      inside_active_area = is_inside_active_area(priv, hw->x, hw->y);
>  
>      /* now we know that these _coordinates_ aren't in the area.
> @@ -2373,7 +2444,6 @@ HandleState(LocalDevicePtr local, struct SynapticsHwState *hw)
>  
>      /* no edge or finger detection outside of area */
>      if (inside_active_area) {
> -	edge = edge_detection(priv, hw->x, hw->y);
>  	finger = SynapticsDetectFinger(priv, hw);
>      }
>  
> diff --git a/src/synapticsstr.h b/src/synapticsstr.h
> index 658721c..5e4090e 100644
> --- a/src/synapticsstr.h
> +++ b/src/synapticsstr.h
> @@ -235,6 +235,8 @@ typedef struct _SynapticsPrivateRec
>      Bool has_pressure;			/* device reports pressure */
>      Bool has_width;			/* device reports finger width */
>      Bool has_scrollbuttons;		/* device has physical scrollbuttons */
> +    Bool is_clickpad;          /* is Clickpad device (one-button) */
> +    struct SynapticsHwState prev_hw;   /* previous h/w state (for clickpad) */

indendation

Cheers,
  Peter

>  
>      enum TouchpadModel model;          /* The detected model */
>  } SynapticsPrivate;
> -- 
> 1.7.2.3