Input: elantech - add resolution query support for v4 hardware

It turns out that v4's firmware provides a command so we can query
the resolution. Let's use it.

Signed-off-by: JJ Ding <jj_ding@emc.com.tw>
Reviewed-by: Daniel Kurtz <djkurtz@chromium.org>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

diff --git a/drivers/input/mouse/elantech.c b/drivers/input/mouse/elantech.c
index 24bb2b5..59bfb70 100644 (file)
--- 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);
                /*

diff --git a/drivers/input/mouse/elantech.h b/drivers/input/mouse/elantech.h
index 08d00bd..46db3be 100644 (file)
--- a/drivers/input/mouse/elantech.h
+++ b/drivers/input/mouse/elantech.h
@@ -20,6 +20,7 @@
 #define ETP_FW_VERSION_QUERY           0x01
 #define ETP_CAPABILITIES_QUERY         0x02
 #define ETP_SAMPLE_QUERY               0x03
+#define ETP_RESOLUTION_QUERY           0x04
 
 /*
  * Command values for register reading or writing