UBUNTU: SAUCE: (no-up) Input: Cypress PS/2 Trackpad simulated multitouch

Upstream doesn't like this patch.

Instead of SEMI_MT, present a full mt interface with simulated contact
positions for >=3 fingers.  Enables e.g. multi-finger tap and drag for
old userspace applications which only count the contact positions.
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>

drivers/input/mouse/cypress_ps2.c

@@ -390,7 +390,9 @@ static int cypress_set_input_params(struct input_dev *input,
 	if (ret < 0)
 		return ret;
 
+#if ( CYPRESS_SIMULATED_MT != 1 )
 	__set_bit(INPUT_PROP_SEMI_MT, input->propbit);
+#endif
 
 	input_abs_set_res(input, ABS_X, cytp->tp_res_x);
 	input_abs_set_res(input, ABS_Y, cytp->tp_res_y);
@@ -478,6 +480,22 @@ static int cypress_parse_packet(struct psmouse *psmouse,
 			((packet[5] & 0x0f) << 8) | packet[7];
 		if (cytp->mode & CYTP_BIT_ABS_PRESSURE)
 			report_data->contacts[1].z = report_data->contacts[0].z;
+#if ( CYPRESS_SIMULATED_MT == 1 )
+		/* simulate contact positions for >2 fingers */
+		if ( report_data->contact_cnt >= 3 ) {
+			int i;
+			for ( i=1; i<report_data->contact_cnt; i++ ) {
+			    report_data->contacts[i].x =
+					    report_data->contacts[0].x
+					    + 100*(i)*((i%2)?-1:1);
+			    report_data->contacts[i].y =
+					    report_data->contacts[0].y;
+			    if (cytp->mode & CYTP_BIT_ABS_PRESSURE)
+				    report_data->contacts[i].z =
+					    report_data->contacts[0].z;
+			}
+		}
+#endif
 	}
 
 	report_data->left = (header_byte & BTN_LEFT_BIT) ? 1 : 0;

drivers/input/mouse/cypress_ps2.h

@@ -130,7 +130,18 @@
 #define RESP_REMOTE_BIT     0x40
 #define RESP_SMBUS_BIT      0x80
 
-#define CYTP_MAX_MT_SLOTS 2
+/*
+ * CYPRESS_SIMULATED_MT
+ *   set to 1 for simulated multitouch (up to 5 contact points)
+ *   set to 0 for SEMI_MT (only 2 corner points, and count of fingers)
+ */
+#define CYPRESS_SIMULATED_MT 1
+
+#if ( CYPRESS_SIMULATED_MT == 1 )
+# define CYTP_MAX_MT_SLOTS 5
+#else
+# define CYTP_MAX_MT_SLOTS 2
+#endif
 
 struct cytp_contact {
 	int x;