| Patrick Williams | c124f4f | 2015-09-15 14:41:29 -0500 | [diff] [blame] | 1 | This is a workaround upstream suggests for use with kernel 4.1. |
| 2 | |
| 3 | Upstream-Status: Inappropriate [temporary work-around] |
| 4 | Signed-Off-By: Jussi Kukkonen <jussi.kukkonen@intel.com> |
| 5 | |
| 6 | |
| 7 | |
| 8 | From: Peter Hutterer <peter.hutterer@who-t.net> |
| 9 | Date: Mon Aug 3 18:23:12 PDT 2015 |
| 10 | Subject: [PATCH v3 libinput] touchpad: serial synaptics need to fake new touches on TRIPLETAP |
| 11 | |
| 12 | On the 4.1 kernels synaptics pretends to have 3 slots (the serial fw only does |
| 13 | 2). This was added to avoid cursor jumps but has since been reverted for 4.2 |
| 14 | (kernel commit dbf3c37086, 4.1.3 is still buggy). In some cases a TRIPLETAP |
| 15 | may be triggered without slot 2 ever activating. |
| 16 | |
| 17 | While there are still those kernels out there, work around this bug by opening |
| 18 | a new touch point where none exists if the fake finger count exceeds the slot |
| 19 | count. |
| 20 | |
| 21 | Reported-by: Jan Alexander Steffens <jan.steffens at gmail.com> |
| 22 | Signed-off-by: Peter Hutterer <peter.hutterer at who-t.net> |
| 23 | Tested-by: Jan Alexander Steffens <jan.steffens at gmail.com> |
| 24 | Reviewed-by: Hans de Goede <hdegoede at redhat.com> |
| 25 | --- |
| 26 | Changes to v2: |
| 27 | - split out the handling instead of having a tmp state variable, see Hans' |
| 28 | comments from v2 |
| 29 | |
| 30 | Mainly sending this to the list again so I have a link to point people to. |
| 31 | If you're on 4.1.x add this patch to your distribution package. |
| 32 | |
| 33 | src/evdev-mt-touchpad.c | 22 ++++++++++++++++------ |
| 34 | 1 file changed, 16 insertions(+), 6 deletions(-) |
| 35 | |
| 36 | diff --git a/src/evdev-mt-touchpad.c b/src/evdev-mt-touchpad.c |
| 37 | index a683d9a..5ef03d5 100644 |
| 38 | --- a/src/evdev-mt-touchpad.c |
| 39 | +++ b/src/evdev-mt-touchpad.c |
| 40 | @@ -369,13 +369,23 @@ tp_restore_synaptics_touches(struct tp_dispatch *tp, |
| 41 | for (i = 0; i < tp->num_slots; i++) { |
| 42 | struct tp_touch *t = tp_get_touch(tp, i); |
| 43 | |
| 44 | - if (t->state != TOUCH_END) |
| 45 | + switch(t->state) { |
| 46 | + case TOUCH_HOVERING: |
| 47 | + case TOUCH_BEGIN: |
| 48 | + case TOUCH_UPDATE: |
| 49 | continue; |
| 50 | - |
| 51 | - /* new touch, move it through begin to update immediately */ |
| 52 | - tp_new_touch(tp, t, time); |
| 53 | - tp_begin_touch(tp, t, time); |
| 54 | - t->state = TOUCH_UPDATE; |
| 55 | + case TOUCH_NONE: |
| 56 | + /* new touch, move it through to begin immediately */ |
| 57 | + tp_new_touch(tp, t, time); |
| 58 | + tp_begin_touch(tp, t, time); |
| 59 | + break; |
| 60 | + case TOUCH_END: |
| 61 | + /* touch just ended ,we need need to restore it to update */ |
| 62 | + tp_new_touch(tp, t, time); |
| 63 | + tp_begin_touch(tp, t, time); |
| 64 | + t->state = TOUCH_UPDATE; |
| 65 | + break; |
| 66 | + } |
| 67 | } |
| 68 | } |
| 69 | |
| 70 | -- |
| 71 | 2.4.3 |
| 72 | |