Input: elantech - adjust hw_version detection logic

This patch fixes some v3 hardware (fw_version: 0x150500) wrongly detected
as v2 hardware.

Reported-by: Marc Dietrich <marvin24@gmx.de>
Signed-off-by: JJ Ding <jj_ding@emc.com.tw>
Tested-By: Marc Dietrich <marvin24@gmx.de>
Acked-by: Éric Piel <eric.piel@tremplin-utc.net>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

1 files changed, 18 insertions, 8 deletions

diff --git a/drivers/input/mouse/elantech.c b/drivers/input/mouse/elantech.c
index 09b93b11a274..e2a9867c19d5 100644
--- a/drivers/input/mouse/elantech.c
+++ b/drivers/input/mouse/elantech.c
@@ -1210,18 +1210,28 @@ static int elantech_reconnect(struct psmouse *psmouse)
  */
 static int elantech_set_properties(struct elantech_data *etd)
 {
+        /* This represents the version of IC body. */
         int ver = (etd->fw_version & 0x0f0000) >> 16;
 
+        /* Early version of Elan touchpads doesn't obey the rule. */
         if (etd->fw_version < 0x020030 || etd->fw_version == 0x020600)
                 etd->hw_version = 1;
-        else if (etd->fw_version < 0x150600)
-                etd->hw_version = 2;
-        else if (ver == 5)
-                etd->hw_version = 3;
-        else if (ver == 6)
-                etd->hw_version = 4;
-        else
-                return -1;
+        else {
+                switch (ver) {
+                case 2:
+                case 4:
+                        etd->hw_version = 2;
+                        break;
+                case 5:
+                        etd->hw_version = 3;
+                        break;
+                case 6:
+                        etd->hw_version = 4;
+                        break;
+                default:
+                        return -1;
+                }
+        }
 
         /*
          * Turn on packet checking by default.