Invert X or Y axis options for usbtouchscreen

[Ondrej Zary]

Hello,
this patch adds support for inverting X or Y axis (or both) to the 
usbtouchscreen driver. Invert Y is needed (together with swap XY) for 
LeadingTouch screens (at least for some of them).

Signed-off-by: Ondrej Zary <[EMAIL PROTECTED]>

-- 
Ondrej Zary

--- linux-2.6.20-orig/drivers/usb/input/usbtouchscreen.c	2007-03-23 15:49:35.000000000 +0100
+++ linux/drivers/usb/input/usbtouchscreen.c	2007-03-23 15:52:02.000000000 +0100
@@ -54,6 +54,12 @@
 static int swap_xy;
 module_param(swap_xy, bool, 0644);
 MODULE_PARM_DESC(swap_xy, "If set X and Y axes are swapped.");
+static int invert_x;
+module_param(invert_x, bool, 0644);
+MODULE_PARM_DESC(invert_x, "Invert X axis.");
+static int invert_y;
+module_param(invert_y, bool, 0644);
+MODULE_PARM_DESC(invert_y, "Invert Y axis.");
 
 /* device specifc data/functions */
 struct usbtouch_usb;
@@ -514,6 +520,7 @@
                                  unsigned char *pkt, int len)
 {
 	struct usbtouch_device_info *type = usbtouch->type;
+	int x, y;
 
 	if (!type->read_data(usbtouch, pkt))
 			return;
@@ -521,12 +528,20 @@
 	input_report_key(usbtouch->input, BTN_TOUCH, usbtouch->touch);
 
 	if (swap_xy) {
-		input_report_abs(usbtouch->input, ABS_X, usbtouch->y);
-		input_report_abs(usbtouch->input, ABS_Y, usbtouch->x);
+		x = usbtouch->y;
+		y = usbtouch->x;
 	} else {
-		input_report_abs(usbtouch->input, ABS_X, usbtouch->x);
-		input_report_abs(usbtouch->input, ABS_Y, usbtouch->y);
+		x = usbtouch->x;
+		y = usbtouch->y;
 	}
+	if (invert_x)
+		x = type->max_xc - x + type->min_xc;
+	if (invert_y)
+		y = type->max_yc - y + type->min_yc;
+
+	input_report_abs(usbtouch->input, ABS_X, x);
+	input_report_abs(usbtouch->input, ABS_Y, y);
+
 	if (type->max_press)
 		input_report_abs(usbtouch->input, ABS_PRESSURE, usbtouch->press);
 	input_sync(usbtouch->input);