Input: synaptics-rmi4 - set reduced reporting mode only when requested

The previous patch "c5ccf2ad3d33 (Input: synaptics-rmi4 - switch to
reduced reporting mode)" enabled reduced reporting mode unintentionally
on some devices, if the firmware was configured with default Delta X/Y
threshold values. The result unintentionally degrade the performance of
some touchpads.

This patch checks to see that the driver is modifying the delta X/Y
thresholds before modifying the reporting mode.

Signed-off-by: Andrew Duggan <aduggan@synaptics.com>
Fixes: c5ccf2ad3d ("Input: synaptics-rmi4 - switch to reduced reporting mode")
Link: https://lore.kernel.org/r/20200312005549.29922-1-aduggan@synaptics.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/input/rmi4/rmi_f11.c

@@ -1203,8 +1203,8 @@ static int rmi_f11_initialize(struct rmi_function *fn)
 	 * If distance threshold values are set, switch to reduced reporting
 	 * mode so they actually get used by the controller.
 	 */
-	if (ctrl->ctrl0_11[RMI_F11_DELTA_X_THRESHOLD] ||
-	    ctrl->ctrl0_11[RMI_F11_DELTA_Y_THRESHOLD]) {
+	if (sensor->axis_align.delta_x_threshold ||
+	    sensor->axis_align.delta_y_threshold) {
 		ctrl->ctrl0_11[0] &= ~RMI_F11_REPORT_MODE_MASK;
 		ctrl->ctrl0_11[0] |= RMI_F11_REPORT_MODE_REDUCED;
 	}