[PATCH] evdev: handle touchscreens without BTN_TOUCH

[Peter Korsgaard]

Some touchscreens (like the Lumio crystaltouch in single touch mode) send
BTN_LEFT rather than BTN_TOUCH:

Input driver version is 1.0.1
Input device ID: bus 0x3 vendor 0x202e product 0x5 version 0x111
Input device name: "LUMIO Inc LUMIO CrystalTouch ver 1.1C"
Supported events:
  Event type 0 (Sync)
  Event type 1 (Key)
    Event code 272 (LeftBtn)
    Event code 273 (RightBtn)
    Event code 274 (MiddleBtn)
  Event type 2 (Relative)
    Event code 9 (Misc)
  Event type 3 (Absolute)
    Event code 0 (X)
      Value    650
      Min        0
      Max     4095
    Event code 1 (Y)
      Value   3221
      Min        0
      Max     4095
  Event type 4 (Misc)
    Event code 4 (ScanCode)
Testing ... (interrupt to exit)
Event: time 1305882024.934011, type 4 (Misc), code 4 (ScanCode), value 90001
Event: time 1305882024.934017, type 1 (Key), code 272 (LeftBtn), value 1
Event: time 1305882024.934029, type 3 (Absolute), code 0 (X), value 270
Event: time 1305882024.934034, type 3 (Absolute), code 1 (Y), value 1513
Event: time 1305882024.934039, type 2 (Relative), code 9 (Misc), value 1

This causes evdev to handle these device as a mouse rather than a
touchscreen, which naturally doesn't work very well. We already internally
translate BTN_TOUCH as BTN_LEFT, so accept this kind of devices as
touchscreens by checking for devices with absolute X/Y and NO relative X/Y
axes.

Signed-off-by: Peter Korsgaard <jacmet at sunsite.dk>
---
 src/evdev.c |    6 ++++--
 1 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/evdev.c b/src/evdev.c
index b1a822b..4f9307f 100644
--- a/src/evdev.c
+++ b/src/evdev.c
@@ -1683,8 +1683,10 @@ EvdevProbe(InputInfoPtr pInfo)
                     pEvdev->flags |= EVDEV_BUTTON_EVENTS;
                 }
             } else if (TestBit(ABS_PRESSURE, pEvdev->abs_bitmask) ||
-                TestBit(BTN_TOUCH, pEvdev->key_bitmask)) {
-                if (has_lmr || TestBit(BTN_TOOL_FINGER, pEvdev->key_bitmask)) {
+                TestBit(BTN_TOUCH, pEvdev->key_bitmask) ||
+                !(TestBit(REL_X, pEvdev->rel_bitmask) &&
+                  TestBit(REL_Y, pEvdev->rel_bitmask))) {
+                if (TestBit(BTN_TOOL_FINGER, pEvdev->key_bitmask)) {
                     xf86IDrvMsg(pInfo, X_PROBED, "Found absolute touchpad.\n");
                     pEvdev->flags |= EVDEV_TOUCHPAD;
                 } else {
-- 
1.7.5.1