[PATCH 1/2] touchpad: when clearing the touchpad state, release fake touches too

[Peter Hutterer]

On Thu, Apr 30, 2015 at 09:49:30AM +0200, Hans de Goede wrote:
> Hi,
> 
> On 30-04-15 07:59, Peter Hutterer wrote:
> >Causes an error message in the device_disable_release_tap_n_drag test. When
> >the touchpad is suspended, all touches are ended in tp_clear_state. Since the
> >hovering support was added, this returns the touches to TOUCH_HOVERING, a
> >subsequent tp_handle_state() will turn them back into TOUCH_BEGIN based on
> >BTN_TOUCH and BTN_TOOL_FINGER still being down.
> >
> >Clear the fake touch buttons as well after ending the touches, this way the
> >touch points are reset to TOUCH_NONE as intended.
> >Once we do that we don't need to manually change the tap finger count when
> >releasing taps, we can just let the count reset naturally.
> >
> >Signed-off-by: Peter Hutterer <peter.hutterer at who-t.net>
> >---
> >  src/evdev-mt-touchpad-tap.c | 1 -
> >  src/evdev-mt-touchpad.c     | 7 +++++++
> >  2 files changed, 7 insertions(+), 1 deletion(-)
> >
> >diff --git a/src/evdev-mt-touchpad-tap.c b/src/evdev-mt-touchpad-tap.c
> >index 0f25e26..bd58bb1 100644
> >--- a/src/evdev-mt-touchpad-tap.c
> >+++ b/src/evdev-mt-touchpad-tap.c
> >@@ -844,7 +844,6 @@ tp_release_all_taps(struct tp_dispatch *tp, uint64_t now)
> >  	}
> >
> >  	tp->tap.state = tp->nfingers_down ? TAP_STATE_DEAD : TAP_STATE_IDLE;
> >-	tp->tap.tap_finger_count = 0;
> >  }
> >
> >  void
> 
> We still need this ("tp->tap.tap_finger_count = 0;") for the
> tp_tap_enabled_update() call, I know you're trying to fix this in the next
> commit, but then at least this belongs in the next commit....

I don't think that's quite correct. The two places this gets called from is:
* tp_suspend->tp_clear_state where all touches are first released, so the
  finger count goes to 0 later when we loop through the touch points
* tp_tap_enabled_update() when we're _disabling_ tapping. in that case too
  it is enough to reset the state to DEAD, at which point no further tap
  events will be generated. The tap finger count can reduce to 0 normally
  when they're lifted.

fwiw, the test suite does pass with this patch applied, and that includes
tests of "tapping is enabled, finger down, now suspend" and similar.
(and it also passes with 2/2 applied)

Cheers,
   Peter


> Also see my comments on the next commit.
> 
> >diff --git a/src/evdev-mt-touchpad.c b/src/evdev-mt-touchpad.c
> >index d5ce880..e017559 100644
> >--- a/src/evdev-mt-touchpad.c
> >+++ b/src/evdev-mt-touchpad.c
> >@@ -750,6 +750,12 @@ tp_destroy(struct evdev_dispatch *dispatch)
> >  }
> >
> >  static void
> >+tp_release_fake_touches(struct tp_dispatch *tp)
> >+{
> >+	tp->fake_touches = 0;
> >+}
> >+
> >+static void
> >  tp_clear_state(struct tp_dispatch *tp)
> >  {
> >  	uint64_t now = libinput_now(tp->device->base.seat->libinput);
> >@@ -772,6 +778,7 @@ tp_clear_state(struct tp_dispatch *tp)
> >  	tp_for_each_touch(tp, t) {
> >  		tp_end_sequence(tp, t, now);
> >  	}
> >+	tp_release_fake_touches(tp);
> >
> >  	tp_handle_state(tp, now);
> >  }
> >
> 
> Regards,
> 
> Hans