--- ums.c.orig	2011-05-27 06:15:17.000000000 +0300
+++ ums.c	2011-06-11 16:37:22.000000000 +0300
@@ -83,12 +83,13 @@ SYSCTL_INT(_hw_usb_ums, OID_AUTO, debug,
 
 #define	MOUSE_FLAGS_MASK (HIO_CONST|HIO_RELATIVE)
 #define	MOUSE_FLAGS (HIO_RELATIVE)
+#define	MOUSE_ABS_FLAGS (0)
 
 #define	UMS_BUF_SIZE      8		/* bytes */
 #define	UMS_IFQ_MAXLEN   50		/* units */
 #define	UMS_BUTTON_MAX   31		/* exclusive, must be less than 32 */
 #define	UMS_BUT(i) ((i) < 3 ? (((i) + 2) % 3) : (i))
-#define	UMS_INFO_MAX	  2		/* maximum number of HID sets */
+#define	UMS_INFO_MAX	  3		/* maximum number of HID sets */
 
 enum {
 	UMS_INTR_DT,
@@ -111,6 +112,11 @@ struct ums_info {
 #define	UMS_FLAG_SBU        0x0010	/* spurious button up events */
 #define	UMS_FLAG_REVZ	    0x0020	/* Z-axis is reversed */
 #define	UMS_FLAG_W_AXIS     0x0040
+#define	UMS_FLAG_X_ABS      0x0100
+#define	UMS_FLAG_Y_ABS      0x0200
+#define	UMS_FLAG_Z_ABS      0x0400
+#define	UMS_FLAG_T_ABS      0x0800
+#define	UMS_FLAG_W_ABS      0x1000
 
 	uint8_t	sc_iid_w;
 	uint8_t	sc_iid_x;
@@ -118,6 +124,11 @@ struct ums_info {
 	uint8_t	sc_iid_z;
 	uint8_t	sc_iid_t;
 	uint8_t	sc_iid_btn[UMS_BUTTON_MAX];
+	int32_t	sc_prev_x;
+	int32_t	sc_prev_y;
+	int32_t	sc_prev_z;
+	int32_t	sc_prev_t;
+	int32_t	sc_prev_w;
 	uint8_t	sc_buttons;
 };
 
@@ -191,6 +202,7 @@ ums_intr_callback(struct usb_xfer *xfer,
 	int32_t dy = 0;
 	int32_t dz = 0;
 	int32_t dt = 0;
+	int32_t temp;
 	uint8_t i;
 	uint8_t id;
 	int len;
@@ -236,29 +248,61 @@ ums_intr_callback(struct usb_xfer *xfer,
 
 	repeat:
 		if ((info->sc_flags & UMS_FLAG_W_AXIS) &&
-		    (id == info->sc_iid_w))
-			dw += hid_get_data(buf, len, &info->sc_loc_w);
+		    (id == info->sc_iid_w)) {
+			temp = hid_get_data(buf, len, &info->sc_loc_w);
+			if (info->sc_flags & UMS_FLAG_W_ABS) {
+				dw += temp - info->sc_prev_w;
+				info->sc_prev_w = temp;
+			} else
+				dw += temp;
+		}
 
 		if ((info->sc_flags & UMS_FLAG_X_AXIS) && 
-		    (id == info->sc_iid_x))
-			dx += hid_get_data(buf, len, &info->sc_loc_x);
+		    (id == info->sc_iid_x)) {
+			temp = hid_get_data(buf, len, &info->sc_loc_x);
+			if (info->sc_flags & UMS_FLAG_X_ABS) {
+				dx += temp - info->sc_prev_x;
+				info->sc_prev_x = temp;
+			} else
+				dx += temp;
+		}
 
 		if ((info->sc_flags & UMS_FLAG_Y_AXIS) &&
-		    (id == info->sc_iid_y))
-			dy = -hid_get_data(buf, len, &info->sc_loc_y);
+		    (id == info->sc_iid_y)) {
+			temp = hid_get_data(buf, len, &info->sc_loc_y);
+			if (info->sc_flags & UMS_FLAG_Y_ABS) {
+				dy -= temp - info->sc_prev_y;
+				info->sc_prev_y = temp;
+			} else
+				dy -= temp;
+		}
 
 		if ((info->sc_flags & UMS_FLAG_Z_AXIS) &&
 		    (id == info->sc_iid_z)) {
-			int32_t temp;
 			temp = hid_get_data(buf, len, &info->sc_loc_z);
-			if (info->sc_flags & UMS_FLAG_REVZ)
-				temp = -temp;
-			dz -= temp;
+			if (info->sc_flags & UMS_FLAG_Z_ABS) {
+				if (info->sc_flags & UMS_FLAG_REVZ)
+					dz += temp - info->sc_prev_z;
+				else
+					dz -= temp - info->sc_prev_z;
+				info->sc_prev_z = temp;
+			} else {
+				if (info->sc_flags & UMS_FLAG_REVZ)
+					dz += temp;
+				else
+					dz -= temp;
+			}
 		}
 
 		if ((info->sc_flags & UMS_FLAG_T_AXIS) &&
-		    (id == info->sc_iid_t))
-			dt -= hid_get_data(buf, len, &info->sc_loc_t);
+		    (id == info->sc_iid_t)) {
+			temp = hid_get_data(buf, len, &info->sc_loc_t);
+			if (info->sc_flags & UMS_FLAG_T_ABS) {
+				dt -= temp - info->sc_prev_t;
+				info->sc_prev_t = temp;
+			} else
+				dt -= temp;
+		}
 
 		for (i = 0; i < info->sc_buttons; i++) {
 			uint32_t mask;
@@ -405,6 +449,8 @@ ums_hid_parse(struct ums_softc *sc, devi
 
 		if ((flags & MOUSE_FLAGS_MASK) == MOUSE_FLAGS) {
 			info->sc_flags |= UMS_FLAG_X_AXIS;
+		} else if ((flags & MOUSE_FLAGS_MASK) == MOUSE_ABS_FLAGS) {
+			info->sc_flags |= UMS_FLAG_X_AXIS | UMS_FLAG_X_ABS;
 		}
 	}
 	if (hid_locate(buf, len, HID_USAGE2(HUP_GENERIC_DESKTOP, HUG_Y),
@@ -412,6 +458,8 @@ ums_hid_parse(struct ums_softc *sc, devi
 
 		if ((flags & MOUSE_FLAGS_MASK) == MOUSE_FLAGS) {
 			info->sc_flags |= UMS_FLAG_Y_AXIS;
+		} else if ((flags & MOUSE_FLAGS_MASK) == MOUSE_ABS_FLAGS) {
+			info->sc_flags |= UMS_FLAG_Y_AXIS | UMS_FLAG_Y_ABS;
 		}
 	}
 	/* Try the wheel first as the Z activator since it's tradition. */
@@ -423,6 +471,8 @@ ums_hid_parse(struct ums_softc *sc, devi
 	    &info->sc_iid_z)) {
 		if ((flags & MOUSE_FLAGS_MASK) == MOUSE_FLAGS) {
 			info->sc_flags |= UMS_FLAG_Z_AXIS;
+		} else if ((flags & MOUSE_FLAGS_MASK) == MOUSE_ABS_FLAGS) {
+			info->sc_flags |= UMS_FLAG_Z_AXIS | UMS_FLAG_Z_ABS;
 		}
 		/*
 		 * We might have both a wheel and Z direction, if so put
@@ -434,6 +484,8 @@ ums_hid_parse(struct ums_softc *sc, devi
 
 			if ((flags & MOUSE_FLAGS_MASK) == MOUSE_FLAGS) {
 				info->sc_flags |= UMS_FLAG_W_AXIS;
+			} else if ((flags & MOUSE_FLAGS_MASK) == MOUSE_ABS_FLAGS) {
+				info->sc_flags |= UMS_FLAG_W_AXIS | UMS_FLAG_W_ABS;
 			}
 		}
 	} else if (hid_locate(buf, len, HID_USAGE2(HUP_GENERIC_DESKTOP,
@@ -442,6 +494,8 @@ ums_hid_parse(struct ums_softc *sc, devi
 
 		if ((flags & MOUSE_FLAGS_MASK) == MOUSE_FLAGS) {
 			info->sc_flags |= UMS_FLAG_Z_AXIS;
+		} else if ((flags & MOUSE_FLAGS_MASK) == MOUSE_ABS_FLAGS) {
+			info->sc_flags |= UMS_FLAG_Z_AXIS | UMS_FLAG_Z_ABS;
 		}
 	}
 	/*
@@ -459,13 +513,18 @@ ums_hid_parse(struct ums_softc *sc, devi
 
 		if ((flags & MOUSE_FLAGS_MASK) == MOUSE_FLAGS) {
 			info->sc_flags |= UMS_FLAG_T_AXIS;
+		} else if ((flags & MOUSE_FLAGS_MASK) == MOUSE_ABS_FLAGS) {
+			info->sc_flags |= UMS_FLAG_T_AXIS | UMS_FLAG_T_ABS;
 		}
 	} else if (hid_locate(buf, len, HID_USAGE2(HUP_CONSUMER,
 		HUC_AC_PAN), hid_input, index, &info->sc_loc_t,
 		&flags, &info->sc_iid_t)) {
 
-		if ((flags & MOUSE_FLAGS_MASK) == MOUSE_FLAGS)
+		if ((flags & MOUSE_FLAGS_MASK) == MOUSE_FLAGS) {
 			info->sc_flags |= UMS_FLAG_T_AXIS;
+		} else if ((flags & MOUSE_FLAGS_MASK) == MOUSE_ABS_FLAGS) {
+			info->sc_flags |= UMS_FLAG_T_AXIS | UMS_FLAG_T_ABS;
+		}
 	}
 	/* figure out the number of buttons */
 
@@ -739,29 +798,21 @@ ums_stop_read(struct usb_fifo *fifo)
 #endif
 
 static void
-ums_put_queue(struct ums_softc *sc, int32_t dx, int32_t dy,
-    int32_t dz, int32_t dt, int32_t buttons)
+ums_put_queue(struct ums_softc *sc, int32_t fdx, int32_t fdy,
+    int32_t fdz, int32_t fdt, int32_t buttons)
 {
+	int scale;
+	int32_t dx, dy, dz, dt;
 	uint8_t buf[8];
 
+start:
 	if (1) {
-
-		if (dx > 254)
-			dx = 254;
-		if (dx < -256)
-			dx = -256;
-		if (dy > 254)
-			dy = 254;
-		if (dy < -256)
-			dy = -256;
-		if (dz > 126)
-			dz = 126;
-		if (dz < -128)
-			dz = -128;
-		if (dt > 126)
-			dt = 126;
-		if (dt < -128)
-			dt = -128;
+		scale = max(max(abs(fdx) / 254, abs(fdy) / 254),
+			    max(abs(fdz) / 126, abs(fdt) / 126)) + 1;
+		dx = fdx / scale;
+		dy = fdy / scale;
+		dz = fdz / scale;
+		dt = fdt / scale;
 
 		buf[0] = sc->sc_mode.syncmask[1];
 		buf[0] |= (~buttons) & MOUSE_MSC_BUTTONS;
@@ -778,6 +829,12 @@ ums_put_queue(struct ums_softc *sc, int3
 		usb_fifo_put_data_linear(sc->sc_fifo.fp[USB_FIFO_RX], buf,
 		    sc->sc_mode.packetsize, 1);
 
+		fdx -= dx;
+		fdy -= dy;
+		fdz -= dz;
+		fdt -= dt;
+		if (fdx != 0 || fdy != 0 || fdz != 0 || fdt != 0)
+			goto start;
 	} else {
 		DPRINTF("Buffer full, discarded packet\n");
 	}