[Linuxwacom-devel] [Patch v3 5/6] Remove duplicate tool type detection

[Egbert E. <ei...@fr...>]

From: Egbert Eich <ei...@su...>

Tool type detection is done in two places: early in usbDispatchEvents()
by calling usbInitToolType() and later on in the same function when the
events are parsed.
usbInitToolType() is used to set (wcmUSBData*)->wcmDeviceType, the
detection that happens later when the events are parsed sets
(WacomDeviceState).device_type. These variables are matched against each
to find the right channel for a device.
If the algorithms used for both set of tool type detection diverge
undesirable effects may happen. Therefore it is advisable to determine the
tool type only once ie. in usbInitToolType() and copy the result to
(WacomDeviceState).device_type if this value is unset.

* Bring the algorithm in usbInitToolType() in sync with the reset:

  Add missing key codes to deviceTypeFromEvent()

  - Add BTN_TOOL_DOUBLETAP and BTN_TOOL_TRIPLETAP, return
    TOUCH_ID for them.

  - Return TOUCH_ID on BTN_TOUCH when protocol level is
    WCM_PROTOCOL_GENERIC and tool is a 1 finger USB touch.

* Delete any duplicate tool type setting

* Add a test for debugging if the device type has changed while in proximity.

Signed-off-by: Egbert Eich <ei...@su...>
Reviewed-by: Jason Gerecke <kil...@gm...>
---
 src/wcmUSB.c | 29 ++++++++++++++++++++---------
 1 file changed, 20 insertions(+), 9 deletions(-)

diff --git a/src/wcmUSB.c b/src/wcmUSB.c
index c060ec5..6932b9f 100644
--- a/src/wcmUSB.c
+++ b/src/wcmUSB.c
@@ -1272,6 +1272,7 @@ static void usbParseAbsMTEvent(WacomCommonPtr common, struct input_event *event)
 
 		case ABS_MT_TRACKING_ID:
 			ds->proximity = (event->value != -1);
+			/* set this here as type for this channel doesn't get set in usbDispatchEvent() */
 			ds->device_type = TOUCH_ID;
 			ds->device_id = TOUCH_DEVICE_ID;
 			ds->sample = (int)GetTimeInMillis();
@@ -1315,7 +1316,6 @@ static void usbParseKeyEvent(WacomCommonPtr common,
 		case BTN_TOOL_PENCIL:
 		case BTN_TOOL_BRUSH:
 		case BTN_TOOL_AIRBRUSH:
-			ds->device_type = STYLUS_ID;
 			/* V5 tools use ABS_MISC to report device_id */
 			if (common->wcmProtocolLevel == WCM_PROTOCOL_4)
 				ds->device_id = STYLUS_DEVICE_ID;
@@ -1326,7 +1326,6 @@ static void usbParseKeyEvent(WacomCommonPtr common,
 			break;
 
 		case BTN_TOOL_RUBBER:
-			ds->device_type = ERASER_ID;
 			/* V5 tools use ABS_MISC to report device_id */
 			if (common->wcmProtocolLevel == WCM_PROTOCOL_4)
 				ds->device_id = ERASER_DEVICE_ID;
@@ -1343,7 +1342,6 @@ static void usbParseKeyEvent(WacomCommonPtr common,
 			DBG(6, common,
 			    "USB mouse detected %x (value=%d)\n",
 			    event->code, event->value);
-			ds->device_type = CURSOR_ID;
 			/* V5 tools use ABS_MISC to report device_id */
 			if (common->wcmProtocolLevel == WCM_PROTOCOL_4)
 				ds->device_id = CURSOR_DEVICE_ID;
@@ -1361,7 +1359,6 @@ static void usbParseKeyEvent(WacomCommonPtr common,
 					DBG(6, common,
 					    "USB 1FG Touch detected %x (value=%d)\n",
 					    event->code, event->value);
-					ds->device_type = TOUCH_ID;
 					ds->device_id = TOUCH_DEVICE_ID;
 					ds->proximity = event->value;
 				}
@@ -1375,7 +1372,6 @@ static void usbParseKeyEvent(WacomCommonPtr common,
 				DBG(6, common,
 				    "USB Pad detected %x (value=%d)\n",
 				event->code, event->value);
-				ds->device_type = PAD_ID;
 				ds->device_id = PAD_DEVICE_ID;
 				ds->proximity = (event->value != 0);
 				break;
@@ -1386,7 +1382,6 @@ static void usbParseKeyEvent(WacomCommonPtr common,
 			DBG(6, common,
 			    "USB Touch detected %x (value=%d)\n",
 			    event->code, event->value);
-			ds->device_type = TOUCH_ID;
 			ds->device_id = TOUCH_DEVICE_ID;
 			ds->proximity = event->value;
 			/* time stamp for 2FGT gesture events */
@@ -1399,7 +1394,6 @@ static void usbParseKeyEvent(WacomCommonPtr common,
 			DBG(6, common,
 			    "USB Touch second finger detected %x (value=%d)\n",
 			    event->code, event->value);
-			ds->device_type = TOUCH_ID;
 			ds->device_id = TOUCH_DEVICE_ID;
 			ds->proximity = event->value;
 			/* time stamp for 2GT gesture events */
@@ -1525,13 +1519,27 @@ static int deviceTypeFromEvent(WacomCommonPtr common, int type, int code, int va
 
 			case BTN_TOOL_FINGER:
 				if ((common->wcmProtocolLevel != WCM_PROTOCOL_GENERIC)
-				    && !private->wcmUseMT)
+				    && !private->wcmUseMT)  /* this isn't in usbParseKeyEvent() */
 					return PAD_ID;
 				else
 					return TOUCH_ID;
 
 			case BTN_TOOL_RUBBER:
 				return ERASER_ID;
+
+			case BTN_TOOL_DOUBLETAP:
+			case BTN_TOOL_TRIPLETAP:
+				return TOUCH_ID;
+
+			case BTN_TOUCH:
+				if (common->wcmProtocolLevel == WCM_PROTOCOL_GENERIC &&
+				    /* 1FG USB touchscreen */
+				    !TabletHasFeature(common, WCM_PEN) &&
+				    TabletHasFeature(common, WCM_1FGT) &&
+				    TabletHasFeature(common, WCM_LCD))
+					return TOUCH_ID;
+				else
+					break;
 		}
 	}
 	else if (type == EV_ABS) {
@@ -1687,9 +1695,12 @@ static void usbDispatchEvents(InputInfoPtr pInfo)
 	ds = &common->wcmChannel[channel].work;
 	dslast = common->wcmChannel[channel].valid.state;
 
+	if (ds->device_type && ds->device_type != private->wcmDeviceType)
+		LogMessageVerbSigSafe(X_ERROR, 0,
+				      "usbDispatchEvents: Device Type mismatch - %d -> %d. This is a BUG.\n",
+				      ds->device_type, private->wcmDeviceType);
 	/* no device type? */
 	if (!ds->device_type && private->wcmDeviceType) {
-		/* tool was on tablet at startup, force type and proximity */
 		ds->device_type = private->wcmDeviceType;
 		ds->proximity = 1;
 	}
-- 
1.8.4.5