Comment 76 for bug 365943

Created attachment 40902
Add JumpyCursorThreshold option patch v5

For those touchpads that don't support multi-finger or sending correct finger width, the jumpy cursor problem is still there. One notable example is the ClickPad found on Lenovo S10-3t whose ClickPad suffers from this jumpy cursor problem very severely, because its buttons also have sensible surface thus every time you click a button without lifting another finger from the pad, such as when trying to drag a window or select text, the cursor jumps, and renders the whole touchpad nigh unusable.

(if you are wondering why Synaptics driver doesn't enable ClickPad mode and limit the touch area thus ignore ABS sent from button area, it's because those ClickPads send out BTN_LEFT and BTN_RIGHT just as normal touchpads so they don't trigger the ClickPad mode, which is designed for ClickPads that never send BTN_RIGHT)

Therefore Alberto Milone's JumpyCursorThreshold option patch is still needed, which is the best solution I've seen so far. I've attached the new patch I ported to head. I've tested it in MeeGo and it works very well (with Threshold set to 250).