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

[Andy Lutomirski]

On 06/23/2016 01:31 AM, Allen Hung wrote:
> 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 <allen_hung@xxxxxxxx>
> ---
>  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@xxxxxxxxxx> # 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.)

--Andy