linux-kernel - Re: synaptics touchpad doesn't click

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Date:	Tue, 15 Dec 2009 08:41:05 +0100
From:	Takashi Iwai <tiwai@...e.de>
To:	Dmitry Torokhov <dmitry.torokhov@...il.com>
Cc:	Alex Chiang <achiang@...com>,
	linux-kernel <linux-kernel@...r.kernel.org>,
	linux-input@...r.kernel.org
Subject: Re: synaptics touchpad doesn't click

At Mon, 14 Dec 2009 23:33:58 -0800,
Dmitry Torokhov wrote:
> 
> On Tue, Dec 15, 2009 at 07:40:55AM +0100, Takashi Iwai wrote:
> > At Mon, 14 Dec 2009 22:26:28 -0800,
> > Dmitry Torokhov wrote:
> > > 
> > > [1  <text/plain; us-ascii (7bit)>]
> > > Hi Alex,
> > > 
> > > On Mon, Dec 14, 2009 at 08:41:27PM -0700, Alex Chiang wrote:
> > > > 
> > > > Thanks, I did grab Takashi's patches and verify that they work
> > > > for me. I tested the separated patches, not the v2 combined
> > > > patch, although it doesn't make any difference based on visual
> > > > inspection of v2.
> > > > 
> > > > If you want, you can add my:
> > > > 
> > > > Tested-by: Alex Chiang <achiang@...com>
> > > 
> > > Thank you very much for testing, however could you please try a slightly
> > > different patch below (I did not quite like that the original patch
> > > mangled device's capability field and how it was reusing 'middle' field
> > > for different things)? It should apply on top of patch that
> > > I am attaching. I hope I did not screw it up too much,
> > 
> > I can't test the patch right now since I'm at home, but I'm afraid
> > it's a bit different behavior.  Namely,
> > 
> > > @@ -330,20 +339,52 @@ static void synaptics_parse_new_hw(unsigned char buf[],
> > >  				   struct synaptics_data *priv,
> > >  				   struct synaptics_hw_state *hw)
> > >  {
> > > -	hw->x = (((buf[3] & 0x10) << 8) | ((buf[1] & 0x0f) << 8) | buf[4]);
> > > -	hw->y = (((buf[3] & 0x20) << 7) | ((buf[1] & 0xf0) << 4) | buf[5]);
> > > +	int x = (((buf[3] & 0x10) << 8) | ((buf[1] & 0x0f) << 8) | buf[4]);
> > > +	int y = (((buf[3] & 0x20) << 7) | ((buf[1] & 0xf0) << 4) | buf[5]);
> > >  
> > >  	hw->z = buf[2];
> > >  	hw->w = (((buf[0] & 0x30) >> 2) |
> > >  		 ((buf[0] & 0x04) >> 1) |
> > >  		 ((buf[3] & 0x04) >> 2));
> > >  
> > > -	hw->left  = buf[0] & 0x01;
> > > -	hw->right = buf[0] & 0x02;
> > > +	if (SYN_CAP_CLICKPAD(priv->ext_cap)) {
> > > +		int click = (buf[0] ^ buf[3]) & 0x01;
> > > +
> > > +		if (click && y < YMIN_NOMINAL) {
> > > +			/*
> > > +			 * User pressed in ClickZone; report new button
> > > +			 * state but use old coordinates and don't report
> > > +			 * any pressure to prevent pointer movement.
> > > +			 */
> > > +			hw->left = x < CLICKPAD_LEFT_BTN_X;
> > > +			hw->right = x > CLICKPAD_RIGHT_BTN_X;
> > > +			hw->middle = x >= CLICKPAD_LEFT_BTN_X &&
> > > +				     x <= CLICKPAD_RIGHT_BTN_X;
> > > +			hw->z = 0;
> > > +
> > > +		} else {
> > > +			/*
> > > +			 * Finger is outside of the ClickZone - report
> > > +			 * current coordinates.
> > > +			 */
> > > +			hw->x = x;
> > > +			hw->y = y;
> > > +
> > > +			if (!click)
> > > +				hw->left = hw->right = hw->middle = 0;
> > > +		}
> > 
> > Here, when you touch outside the button area, left/right/middle are
> > always zero because hw was initialized.  So the above code gives the
> > click "released" state outside the button area.
> > 
> 
> No, I got rid of resetting hw state to 0.

Ah, it's in the second patch.

But looking at that one, hw is a local variable and still doesn't
inherit from the previous state, no?  If so, the button state will be
just a random value.


thanks,

Takashi
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