1 files changed, 37 insertions, 0 deletions

diff --git a/drivers/input/mouse/elantech.c b/drivers/input/mouse/elantech.c
index 24bb2b5f5667..59bfb70d330a 100644
--- a/drivers/input/mouse/elantech.c
+++ b/drivers/input/mouse/elantech.c
@@ -931,6 +931,30 @@ static int elantech_set_range(struct psmouse *psmouse,
 }
 
 /*
+ * (value from firmware) * 10 + 790 = dpi
+ * we also have to convert dpi to dots/mm (*10/254 to avoid floating point)
+ */
+static unsigned int elantech_convert_res(unsigned int val)
+{
+        return (val * 10 + 790) * 10 / 254;
+}
+
+static int elantech_get_resolution_v4(struct psmouse *psmouse,
+                                      unsigned int *x_res,
+                                      unsigned int *y_res)
+{
+        unsigned char param[3];
+
+        if (elantech_send_cmd(psmouse, ETP_RESOLUTION_QUERY, param))
+                return -1;
+
+        *x_res = elantech_convert_res(param[1] & 0x0f);
+        *y_res = elantech_convert_res((param[1] & 0xf0) >> 4);
+
+        return 0;
+}
+
+/*
  * Set the appropriate event bits for the input subsystem
  */
 static int elantech_set_input_params(struct psmouse *psmouse)
@@ -938,6 +962,7 @@ static int elantech_set_input_params(struct psmouse *psmouse)
         struct input_dev *dev = psmouse->dev;
         struct elantech_data *etd = psmouse->private;
         unsigned int x_min = 0, y_min = 0, x_max = 0, y_max = 0, width = 0;
+        unsigned int x_res = 0, y_res = 0;
 
         if (elantech_set_range(psmouse, &x_min, &y_min, &x_max, &y_max, &width))
                 return -1;
@@ -985,10 +1010,20 @@ static int elantech_set_input_params(struct psmouse *psmouse)
                 break;
 
         case 4:
+                if (elantech_get_resolution_v4(psmouse, &x_res, &y_res)) {
+                        /*
+                         * if query failed, print a warning and leave the values
+                         * zero to resemble synaptics.c behavior.
+                         */
+                        psmouse_warn(psmouse, "couldn't query resolution data.\n");
+                }
+
                 __set_bit(BTN_TOOL_QUADTAP, dev->keybit);
                 /* For X to recognize me as touchpad. */
                 input_set_abs_params(dev, ABS_X, x_min, x_max, 0, 0);
                 input_set_abs_params(dev, ABS_Y, y_min, y_max, 0, 0);
+                input_abs_set_res(dev, ABS_X, x_res);
+                input_abs_set_res(dev, ABS_Y, y_res);
                 /*
                  * range of pressure and width is the same as v2,
                  * report ABS_PRESSURE, ABS_TOOL_WIDTH for compatibility.
@@ -1001,6 +1036,8 @@ static int elantech_set_input_params(struct psmouse *psmouse)
                 input_mt_init_slots(dev, ETP_MAX_FINGERS);
                 input_set_abs_params(dev, ABS_MT_POSITION_X, x_min, x_max, 0, 0);
                 input_set_abs_params(dev, ABS_MT_POSITION_Y, y_min, y_max, 0, 0);
+                input_abs_set_res(dev, ABS_MT_POSITION_X, x_res);
+                input_abs_set_res(dev, ABS_MT_POSITION_Y, y_res);
                 input_set_abs_params(dev, ABS_MT_PRESSURE, ETP_PMIN_V2,
                                      ETP_PMAX_V2, 0, 0);
                 /*