1 files changed, 30 insertions, 3 deletions

diff --git a/drivers/input/mouse/psmouse-base.c b/drivers/input/mouse/psmouse-base.c
index 5f21532c24ff..8bc9f51ae6c2 100644
--- a/drivers/input/mouse/psmouse-base.c
+++ b/drivers/input/mouse/psmouse-base.c
@@ -150,9 +150,20 @@ static psmouse_ret_t psmouse_process_byte(struct psmouse *psmouse, struct pt_reg
  */
 
         if (psmouse->type == PSMOUSE_IMEX) {
-                input_report_rel(dev, REL_WHEEL, (int) (packet[3] & 8) - (int) (packet[3] & 7));
-                input_report_key(dev, BTN_SIDE, (packet[3] >> 4) & 1);
-                input_report_key(dev, BTN_EXTRA, (packet[3] >> 5) & 1);
+                switch (packet[3] & 0xC0) {
+                        case 0x80: /* vertical scroll on IntelliMouse Explorer 4.0 */
+                                input_report_rel(dev, REL_WHEEL, (int) (packet[3] & 32) - (int) (packet[3] & 31));
+                                break;
+                        case 0x40: /* horizontal scroll on IntelliMouse Explorer 4.0 */
+                                input_report_rel(dev, REL_HWHEEL, (int) (packet[3] & 32) - (int) (packet[3] & 31));
+                                break;
+                        case 0x00:
+                        case 0xC0:
+                                input_report_rel(dev, REL_WHEEL, (int) (packet[3] & 8) - (int) (packet[3] & 7));
+                                input_report_key(dev, BTN_SIDE, (packet[3] >> 4) & 1);
+                                input_report_key(dev, BTN_EXTRA, (packet[3] >> 5) & 1);
+                                break;
+                }
         }
 
 /*
@@ -466,9 +477,25 @@ static int im_explorer_detect(struct psmouse *psmouse, int set_properties)
         if (param[0] != 4)
                 return -1;
 
+/* Magic to enable horizontal scrolling on IntelliMouse 4.0 */
+        param[0] = 200;
+        ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE);
+        param[0] =  80;
+        ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE);
+        param[0] =  40;
+        ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE);
+
+        param[0] = 200;
+        ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE);
+        param[0] = 200;
+        ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE);
+        param[0] =  60;
+        ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE);
+
         if (set_properties) {
                 set_bit(BTN_MIDDLE, psmouse->dev->keybit);
                 set_bit(REL_WHEEL, psmouse->dev->relbit);
+                set_bit(REL_HWHEEL, psmouse->dev->relbit);
                 set_bit(BTN_SIDE, psmouse->dev->keybit);
                 set_bit(BTN_EXTRA, psmouse->dev->keybit);