From df66c5bf79bb6421ac70ea8c102b6a630ae705f4 Mon Sep 17 00:00:00 2001 From: Peter Hutterer Date: Wed, 7 Aug 2013 11:04:46 +1000 Subject: [PATCH] evdev: get the current slot value from the absinfo struct or mtdev If touches are already present on the device, absinfo has the currently active touch slot. There's a race condition where the slot may change before we enable the fd and we thus miss out on the ABS_MT_SLOT event. It's still slightly more correct than assuming whatever comes next is slot 0. --- src/evdev.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/src/evdev.c b/src/evdev.c index 0cf5aa2e..24f52ca6 100644 --- a/src/evdev.c +++ b/src/evdev.c @@ -469,7 +469,6 @@ evdev_handle_device(struct evdev_device *device) device->abs.min_y = absinfo.minimum; device->abs.max_y = absinfo.maximum; device->is_mt = 1; - device->mt.slot = 0; device->caps |= EVDEV_TOUCH; if (!TEST_BIT(abs_bits, ABS_MT_SLOT)) { @@ -479,6 +478,11 @@ evdev_handle_device(struct evdev_device *device) device->devnode); return 0; } + device->mt.slot = device->mtdev->caps.slot.value; + } else { + ioctl(device->fd, EVIOCGABS(ABS_MT_SLOT), + &absinfo); + device->mt.slot = absinfo.value; } } }