udev: don't assign INPUT_ID_MOUSE to a touchpad/joystick/touchscreen (systemd#8259)

whot · keszybz · commit 774ff9ba69c0 · 2018-02-23T09:36:45.000+01:00
If a touchpad has MT axes only but not ABS_X/ABS_Y (DualShock 4 controller), then we hit both the conditions is_touchpad and the later check for !has_abs_axes here, assigning is_mouse and ID_INPUT_MOUSE later. This is a bug, we historically only assigned either of of the pointing device tags ID_INPUT_MOUSE/TOUCHPAD/JOYSTICK/TOUCHSCREEN, never multiple of them. Note that we cannot just check for has_abs_axes and has_mt_coordinates because the apple touch mouse has both. We really need to check if the device has already been assigned something else. https://bugs.freedesktop.org/show_bug.cgi?id=105050
diff --git a/src/udev/udev-builtin-input_id.c b/src/udev/udev-builtin-input_id.c
@@ -233,7 +233,8 @@ static bool test_pointers(struct udev_device *dev,
                         is_touchscreen = true;
         }
 
-        if (has_mouse_button &&
+        if (!is_tablet && !is_touchpad && !is_joystick &&
+            has_mouse_button &&
             (has_rel_coordinates ||
             !has_abs_coordinates)) /* mouse buttons and no axis */
                 is_mouse = true;

Original file line number	Diff line number	Diff line change
`@@ -233,7 +233,8 @@ static bool test_pointers(struct udev_device *dev,`
`233`	`233`	`is_touchscreen = true;`
`234`	`234`	`}`
`235`	`235`
`236`		`- if (has_mouse_button &&`
	`236`	`+ if (!is_tablet && !is_touchpad && !is_joystick &&`
	`237`	`+ has_mouse_button &&`
`237`	`238`	`(has_rel_coordinates \|\|`
`238`	`239`	`!has_abs_coordinates)) /* mouse buttons and no axis */`
`239`	`240`	`is_mouse = true;`