Input: synaptics - fix resolution for manually provided min/max

commit 421e08c41fda fixed the reported min/max for the X and Y axis,
but unfortunately, it broke the resolution of those same axis.

On the t540p, the resolution is the same regarding X and Y. It is not
a problem for xf86-input-synaptics because this driver is only interested
in the ratio between X and Y.
Unfortunately, xf86-input-cmt uses directly the resolution, and having a
null resolution leads to some divide by 0 errors, which are translated by
-infinity in the resulting coordinates.

Reported-by: Peter Hutterer <peter.hutterer@who-t.net>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

1 files changed, 10 insertions, 9 deletions

diff --git a/drivers/input/mouse/synaptics.c b/drivers/input/mouse/synaptics.c
index c5ec703c727e..ec772d962f06 100644
--- a/drivers/input/mouse/synaptics.c
+++ b/drivers/input/mouse/synaptics.c
@@ -347,15 +347,6 @@ static int synaptics_resolution(struct psmouse *psmouse)
         unsigned char resp[3];
         int i;
 
-        for (i = 0; min_max_pnpid_table[i].pnp_ids; i++)
-                if (matches_pnp_id(psmouse, min_max_pnpid_table[i].pnp_ids)) {
-                        priv->x_min = min_max_pnpid_table[i].x_min;
-                        priv->x_max = min_max_pnpid_table[i].x_max;
-                        priv->y_min = min_max_pnpid_table[i].y_min;
-                        priv->y_max = min_max_pnpid_table[i].y_max;
-                        return 0;
-                }
-
         if (SYN_ID_MAJOR(priv->identity) < 4)
                 return 0;
 
@@ -366,6 +357,16 @@ static int synaptics_resolution(struct psmouse *psmouse)
                 }
         }
 
+        for (i = 0; min_max_pnpid_table[i].pnp_ids; i++) {
+                if (matches_pnp_id(psmouse, min_max_pnpid_table[i].pnp_ids)) {
+                        priv->x_min = min_max_pnpid_table[i].x_min;
+                        priv->x_max = min_max_pnpid_table[i].x_max;
+                        priv->y_min = min_max_pnpid_table[i].y_min;
+                        priv->y_max = min_max_pnpid_table[i].y_max;
+                        return 0;
+                }
+        }
+
         if (SYN_EXT_CAP_REQUESTS(priv->capabilities) >= 5 &&
             SYN_CAP_MAX_DIMENSIONS(priv->ext_cap_0c)) {
                 if (synaptics_send_cmd(psmouse, SYN_QUE_EXT_MAX_COORDS, resp)) {