[feat] Make touch work on the H2O2 (#3715)

frontend/device/input.lua

@@ -376,16 +376,22 @@ end.  Upon receiving an MT event, one simply updates the appropriate
 attribute of the current slot.
 --]]
 function Input:handleTouchEv(ev)
+    local function switchSlotTo(value)
+        if self.cur_slot ~= value then
+            table.insert(self.MTSlots, self:getMtSlot(value))
+        end
+        self.cur_slot = value
+    end
     if ev.type == EV_ABS then
         if #self.MTSlots == 0 then
             table.insert(self.MTSlots, self:getMtSlot(self.cur_slot))
         end
         if ev.code == ABS_MT_SLOT then
-            if self.cur_slot ~= ev.value then
-                table.insert(self.MTSlots, self:getMtSlot(ev.value))
-            end
-            self.cur_slot = ev.value
+            switchSlotTo(ev.value)
         elseif ev.code == ABS_MT_TRACKING_ID then
+            if self.snow_protocol then
+                switchSlotTo(ev.value)
+            end
             self:setCurrentMtSlot("id", ev.value)
         elseif ev.code == ABS_MT_POSITION_X then
             self:setCurrentMtSlot("x", ev.value)
@@ -411,10 +417,32 @@ function Input:handleTouchEv(ev)
         if ev.code == SYN_REPORT then
             for _, MTSlot in pairs(self.MTSlots) do
                 self:setMtSlot(MTSlot.slot, "timev", TimeVal:new(ev.time))
+                if self.snow_protocol then
+                    -- if a slot appears in the current touch event, set "used"
+                    self:setMtSlot(MTSlot.slot, "used", true)
+                end
+            end
+            if self.snow_protocol then
+                -- reset every slot that doesn't appear in the current touch event
+                -- (because on the H2O2, this is the only way we detect finger-up)
+                self.MTSlots = {}
+                for _, slot in pairs(self.ev_slots) do
+                    table.insert(self.MTSlots, slot)
+                    if not slot.used then
+                        slot.id = -1
+                        slot.timev = TimeVal:new(ev.time)
+                    end
+                end
             end
             -- feed ev in all slots to state machine
             local touch_ges = self.gesture_detector:feedEvent(self.MTSlots)
             self.MTSlots = {}
+            if self.snow_protocol then
+                -- go through all the ev_slots and clear used
+                for _, slot in pairs(self.ev_slots) do
+                    slot.used = nil
+                end
+            end
             if touch_ges then
                 self:gestureAdjustHook(touch_ges)
                 return Event:new("Gesture",

frontend/device/kobo/device.lua

@@ -104,7 +104,8 @@ local KoboPhoenix = Kobo:new{
 local KoboSnow = Kobo:new{
     model = "Kobo_snow",
     hasFrontlight = yes,
-    touch_alyssum_protocol = true,
+    touch_snow_protocol = true,
+    touch_mirrored_x = false,
     touch_probe_ev_epoch_time = true,
     display_dpi = 265,
     -- the bezel covers the top 11 pixels:
@@ -302,6 +303,10 @@ function Kobo:initEventAdjustHooks()
         self.input:registerEventAdjustHook(adjustTouchAlyssum)
     end
 
+    if self.touch_snow_protocol then
+        self.input.snow_protocol = true
+    end
+
     if self.touch_probe_ev_epoch_time then
         self.input:registerEventAdjustHook(function(_, ev)
             probeEvEpochTime(_, ev)