diff --git a/libevdev/libevdev.c b/libevdev/libevdev.c index dd03d77..a77c466 100644 --- a/libevdev/libevdev.c +++ b/libevdev/libevdev.c @@ -552,26 +552,26 @@ static int sync_mt_state(struct libevdev *dev, int create_events) { int rc; - int i; + int axis, slot; int ioctl_success = 0; struct mt_state { int code; int val[MAX_SLOTS]; - } mt_state[ABS_MT_CNT]; + } mt_state; + unsigned long slot_update[NLONGS(MAX_SLOTS * ABS_MT_CNT)] = {0}; - memset(&mt_state, 0, sizeof(mt_state)); +#define AXISBIT(_slot, _axis) (_slot * ABS_MT_CNT + _axis - ABS_MT_MIN) - for (i = ABS_MT_MIN; i <= ABS_MT_MAX; i++) { - int idx; - if (i == ABS_MT_SLOT) + for (axis = ABS_MT_MIN; axis <= ABS_MT_MAX; axis++) { + if (axis == ABS_MT_SLOT) continue; - if (!libevdev_has_event_code(dev, EV_ABS, i)) + if (!libevdev_has_event_code(dev, EV_ABS, axis)) continue; - idx = i - ABS_MT_MIN; - mt_state[idx].code = i; - rc = ioctl(dev->fd, EVIOCGMTSLOTS(sizeof(struct mt_state)), &mt_state[idx]); + memset(&mt_state, 0, sizeof(mt_state)); + mt_state.code = axis; + rc = ioctl(dev->fd, EVIOCGMTSLOTS(sizeof(struct mt_state)), &mt_state); if (rc < 0) { /* if the first ioctl fails with -EINVAL, chances are the kernel doesn't support the ioctl. Simply continue */ @@ -579,39 +579,49 @@ sync_mt_state(struct libevdev *dev, int create_events) rc = 0; } else /* if the second, ... ioctl fails, really fail */ goto out; - } else if (ioctl_success == 0) - ioctl_success = 1; + } else { + if (ioctl_success == 0) + ioctl_success = 1; + + for (slot = 0; slot < min(dev->num_slots, MAX_SLOTS); slot++) { + + if (*slot_value(dev, slot, axis) == mt_state.val[slot]) + continue; + + *slot_value(dev, slot, axis) = mt_state.val[slot]; + + set_bit(slot_update, AXISBIT(slot, axis)); + /* note that this slot has updates */ + set_bit(slot_update, AXISBIT(slot, ABS_MT_SLOT)); + } + + + } } - for (i = 0; i < min(dev->num_slots, MAX_SLOTS); i++) { - int j; + for (slot = 0; create_events && slot < min(dev->num_slots, MAX_SLOTS); slot++) { struct input_event *ev; - if (create_events) { - ev = queue_push(dev); - init_event(dev, ev, EV_ABS, ABS_MT_SLOT, i); - } + if (!bit_is_set(slot_update, AXISBIT(slot, ABS_MT_SLOT))) + continue; - for (j = ABS_MT_MIN; j <= ABS_MT_MAX; j++) { - int jdx = j - ABS_MT_MIN; + ev = queue_push(dev); + init_event(dev, ev, EV_ABS, ABS_MT_SLOT, slot); - if (j == ABS_MT_SLOT) + for (axis = ABS_MT_MIN; axis <= ABS_MT_MAX; axis++) { + if (axis == ABS_MT_SLOT || + !libevdev_has_event_code(dev, EV_ABS, axis)) continue; - if (!libevdev_has_event_code(dev, EV_ABS, j)) - continue; - - if (*slot_value(dev, i, j) == mt_state[jdx].val[i]) - continue; - - if (create_events) { + if (bit_is_set(slot_update, AXISBIT(slot, axis))) { ev = queue_push(dev); - init_event(dev, ev, EV_ABS, j, mt_state[jdx].val[i]); + init_event(dev, ev, EV_ABS, axis, *slot_value(dev, slot, axis)); } - *slot_value(dev, i, j) = mt_state[jdx].val[i]; } } +#undef AXISBIT + rc = 0; out: return rc ? -errno : 0;