2 files changed, 30 insertions, 0 deletions

diff --git a/drivers/input/mouse/psmouse-base.c b/drivers/input/mouse/psmouse-base.c
index f15f695777f8..b9f0fb2530e2 100644
--- a/drivers/input/mouse/psmouse-base.c
+++ b/drivers/input/mouse/psmouse-base.c
@@ -178,6 +178,15 @@ static psmouse_ret_t psmouse_process_byte(struct psmouse *psmouse)
         }
 
 /*
+ * Cortron PS2 Trackball reports SIDE button on the 4th bit of the first
+ * byte.
+ */
+        if (psmouse->type == PSMOUSE_CORTRON) {
+                input_report_key(dev, BTN_SIDE, (packet[0] >> 3) & 1);
+                packet[0] |= 0x08;
+        }
+
+/*
  * Generic PS/2 Mouse
  */
 
@@ -539,6 +548,20 @@ static int ps2bare_detect(struct psmouse *psmouse, int set_properties)
         return 0;
 }
 
+/*
+ * Cortron PS/2 protocol detection. There's no special way to detect it, so it
+ * must be forced by sysfs protocol writing.
+ */
+static int cortron_detect(struct psmouse *psmouse, int set_properties)
+{
+        if (set_properties) {
+                psmouse->vendor = "Cortron";
+                psmouse->name = "PS/2 Trackball";
+                set_bit(BTN_SIDE, psmouse->dev->keybit);
+        }
+
+        return 0;
+}
 
 /*
  * psmouse_extensions() probes for any extensions to the basic PS/2 protocol
@@ -740,6 +763,12 @@ static const struct psmouse_protocol psmouse_protocols[] = {
         },
 #endif
         {
+                .type           = PSMOUSE_CORTRON,
+                .name           = "CortronPS/2",
+                .alias          = "cortps",
+                .detect         = cortron_detect,
+        },
+        {
                 .type           = PSMOUSE_AUTO,
                 .name           = "auto",
                 .alias          = "any",
diff --git a/drivers/input/mouse/psmouse.h b/drivers/input/mouse/psmouse.h
index 3964e8acbc54..27a68835b5ba 100644
--- a/drivers/input/mouse/psmouse.h
+++ b/drivers/input/mouse/psmouse.h
@@ -88,6 +88,7 @@ enum psmouse_type {
         PSMOUSE_LIFEBOOK,
         PSMOUSE_TRACKPOINT,
         PSMOUSE_TOUCHKIT_PS2,
+        PSMOUSE_CORTRON,
         PSMOUSE_AUTO            /* This one should always be last */
 };