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[3/4] Input: Add ABS_RECT_* legacy multitouch evdev codes

Message ID 1292361672-2581-4-git-send-email-chase.douglas@canonical.com (mailing list archive)
State New, archived
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Commit Message

Chase Douglas Dec. 14, 2010, 9:21 p.m. UTC
None
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Patch

diff --git a/Documentation/input/evdev-codes.txt b/Documentation/input/evdev-codes.txt
index 69c810f..65db20e 100644
--- a/Documentation/input/evdev-codes.txt
+++ b/Documentation/input/evdev-codes.txt
@@ -116,6 +116,16 @@  A few EV_ABS codes have special meanings:
     should only be used while the tool is in close proximity of the device. If
     the input device may be used freely in three dimensions, consider ABS_Z
     instead.
+* ABS_RECT_MIN_X, ABS_RECT_MIN_Y, ABS_RECT_MAX_X, ABS_RECT_MAX_Y:
+  - Used to convey partial multitouch support. Some legacy device multitouch
+    coordinates are not accurate enough to be relied on directly. For example,
+    the device may give coordinates (X1, Y1) and (X2, Y2) for two touch points,
+    but in reality the touches are at (X1, Y2) and (X2, Y1). The maximum and
+    minimum axis values are accurate, so they may be used to provide a rectangle
+    bounding box for the touches.
+    The values for these codes are undefined unless two or more touches are
+    active, designated by BTN_TOOL_DOUBLETAP or higher order code being set to
+    1.
 * ABS_MT_<name>:
   - Used to describe multitouch input events. Please see
     multi-touch-protocol.txt for details.
diff --git a/include/linux/input.h b/include/linux/input.h
index cd0618c..5acdc60 100644
--- a/include/linux/input.h
+++ b/include/linux/input.h
@@ -719,6 +719,11 @@  struct input_keymap_entry {
 
 #define ABS_VOLUME		0x20
 
+#define ABS_RECT_MIN_X		0x21
+#define ABS_RECT_MIN_Y		0x22
+#define ABS_RECT_MAX_X		0x23
+#define ABS_RECT_MAX_Y		0x24
+
 #define ABS_MISC		0x28
 
 #define ABS_MT_SLOT		0x2f	/* MT slot being modified */