Input: synaptics - set dimensions as reported by firmware

Newer Synaptics firmware allows to query maximim dimensions reported by
device, let's use this data.

Tested-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
diff --git a/drivers/input/mouse/synaptics.c b/drivers/input/mouse/synaptics.c
index ebd7a99..52bb1de 100644
--- a/drivers/input/mouse/synaptics.c
+++ b/drivers/input/mouse/synaptics.c
@@ -36,6 +36,8 @@
  * The x/y limits are taken from the Synaptics TouchPad interfacing Guide,
  * section 2.3.2, which says that they should be valid regardless of the
  * actual size of the sensor.
+ * Note that newer firmware allows querying device for maximum useable
+ * coordinates.
  */
 #define XMIN_NOMINAL 1472
 #define XMAX_NOMINAL 5472
@@ -194,23 +196,33 @@
 }
 
 /*
- * Read touchpad resolution
+ * Read touchpad resolution and maximum reported coordinates
  * Resolution is left zero if touchpad does not support the query
  */
 static int synaptics_resolution(struct psmouse *psmouse)
 {
 	struct synaptics_data *priv = psmouse->private;
 	unsigned char res[3];
+	unsigned char max[3];
 
 	if (SYN_ID_MAJOR(priv->identity) < 4)
-		return 0;
 
-	if (synaptics_send_cmd(psmouse, SYN_QUE_RESOLUTION, res))
-		return 0;
+	if (synaptics_send_cmd(psmouse, SYN_QUE_RESOLUTION, res) == 0) {
+		if (res[0] != 0 && (res[1] & 0x80) && res[2] != 0) {
+			priv->x_res = res[0]; /* x resolution in units/mm */
+			priv->y_res = res[2]; /* y resolution in units/mm */
+		}
+	}
 
-	if ((res[0] != 0) && (res[1] & 0x80) && (res[2] != 0)) {
-		priv->x_res = res[0]; /* x resolution in units/mm */
-		priv->y_res = res[2]; /* y resolution in units/mm */
+	if (SYN_EXT_CAP_REQUESTS(priv->capabilities) >= 5 &&
+	    SYN_CAP_MAX_DIMENSIONS(priv->ext_cap_0c)) {
+		if (synaptics_send_cmd(psmouse, SYN_QUE_EXT_DIMENSIONS, max)) {
+			printk(KERN_ERR "Synaptics claims to have dimensions query,"
+			       " but I'm not able to read it.\n");
+		} else {
+			priv->x_max = (max[0] << 5) | ((max[1] & 0x0f) << 1);
+			priv->y_max = (max[2] << 5) | ((max[1] & 0xf0) >> 3);
+		}
 	}
 
 	return 0;
@@ -578,8 +590,10 @@
 	int i;
 
 	__set_bit(EV_ABS, dev->evbit);
-	input_set_abs_params(dev, ABS_X, XMIN_NOMINAL, XMAX_NOMINAL, 0, 0);
-	input_set_abs_params(dev, ABS_Y, YMIN_NOMINAL, YMAX_NOMINAL, 0, 0);
+	input_set_abs_params(dev, ABS_X,
+			     XMIN_NOMINAL, priv->x_max ?: XMAX_NOMINAL, 0, 0);
+	input_set_abs_params(dev, ABS_Y,
+			     YMIN_NOMINAL, priv->y_max ?: YMAX_NOMINAL, 0, 0);
 	input_set_abs_params(dev, ABS_PRESSURE, 0, 255, 0, 0);
 	__set_bit(ABS_TOOL_WIDTH, dev->absbit);