Re: [PATCH 1/2] Revert "HID: multitouch: enable palm rejection if device implements confidence usage"

On Mon, Jun 27, 2016 at 10:55 AM, Andy Lutomirski [off-list ref] wrote:

On 06/23/2016 01:31 AM, Allen Hung wrote:

quoted

This reverts commit 25a84db15b3f ("HID: multitouch: enable palm rejection
if device implements confidence usage")

The commit enables palm rejection for Win8 Precision Touchpad devices but
the quirk MT_QUIRK_VALID_IS_CONFIDENCE it is using is not working very
properly. This quirk is originally designed for some WIn7 touchscreens.
Use
of this for a Win8 Precision Touchpad will cause unexpected pointer
jumping
problem.

Signed-off-by: Allen Hung <redacted>
---
 drivers/hid/hid-multitouch.c | 5 -----
 1 file changed, 5 deletions(-)

diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c
index 95b7d61..4ef7006 100644
--- a/drivers/hid/hid-multitouch.c
+++ b/drivers/hid/hid-multitouch.c

@@ -502,11 +502,6 @@ static int mt_touch_input_mapping(struct hid_device

*hdev, struct hid_input *hi,
                        mt_store_field(usage, td, hi);
                        return 1;
                case HID_DG_CONFIDENCE:
-                       if (cls->name == MT_CLS_WIN_8 &&
-                               field->application == HID_DG_TOUCHPAD) {
-                               cls->quirks &= ~MT_QUIRK_ALWAYS_VALID;
-                               cls->quirks |=
MT_QUIRK_VALID_IS_CONFIDENCE;
-                       }
                        mt_store_field(usage, td, hi);
                        return 1;
                case HID_DG_TIPSWITCH:

This and patch 2 are:

Tested-by: Andy Lutomirski <luto@kernel.org> # XPS 13 9350, BIOS 1.4.3

(And I'm curious why 1.4.3 seems to have been pulled.  Might it have been
this issue?  For better or for worse, I upgraded in the narrow window in
which it was available on Dell's website.)

I should amend that Tested-by slightly: these patches seem to make the
problem merely about as bad as it was before.  It's still not perfect
-- I still occasionally get stuck touches.

--Andy