1 files changed, 32 insertions, 12 deletions

diff --git a/drivers/input/touchscreen/wacom_w8001.c b/drivers/input/touchscreen/wacom_w8001.c
index 49bce13838be..8ed53aded2d3 100644
--- a/drivers/input/touchscreen/wacom_w8001.c
+++ b/drivers/input/touchscreen/wacom_w8001.c
@@ -19,6 +19,7 @@
 #include <linux/serio.h>
 #include <linux/init.h>
 #include <linux/ctype.h>
+#include <linux/delay.h>
 
 #define DRIVER_DESC     "Wacom W8001 serial touchscreen driver"
 
@@ -37,6 +38,7 @@ MODULE_LICENSE("GPL");
 
 #define W8001_QUERY_PACKET      0x20
 
+#define W8001_CMD_STOP          '0'
 #define W8001_CMD_START         '1'
 #define W8001_CMD_QUERY         '*'
 #define W8001_CMD_TOUCHQUERY    '%'
@@ -279,24 +281,46 @@ static int w8001_setup(struct w8001 *w8001)
         struct w8001_coord coord;
         int error;
 
-        error = w8001_command(w8001, W8001_CMD_QUERY, true);
+        error = w8001_command(w8001, W8001_CMD_STOP, false);
         if (error)
                 return error;
 
-        parse_data(w8001->response, &coord);
+        msleep(250);    /* wait 250ms before querying the device */
 
-        input_set_abs_params(dev, ABS_X, 0, coord.x, 0, 0);
-        input_set_abs_params(dev, ABS_Y, 0, coord.y, 0, 0);
-        input_set_abs_params(dev, ABS_PRESSURE, 0, coord.pen_pressure, 0, 0);
-        input_set_abs_params(dev, ABS_TILT_X, 0, coord.tilt_x, 0, 0);
-        input_set_abs_params(dev, ABS_TILT_Y, 0, coord.tilt_y, 0, 0);
+        /* penabled? */
+        error = w8001_command(w8001, W8001_CMD_QUERY, true);
+        if (!error) {
+                __set_bit(BTN_TOOL_PEN, dev->keybit);
+                __set_bit(BTN_TOOL_RUBBER, dev->keybit);
+                __set_bit(BTN_STYLUS, dev->keybit);
+                __set_bit(BTN_STYLUS2, dev->keybit);
+                parse_data(w8001->response, &coord);
+
+                input_set_abs_params(dev, ABS_X, 0, coord.x, 0, 0);
+                input_set_abs_params(dev, ABS_Y, 0, coord.y, 0, 0);
+                input_set_abs_params(dev, ABS_PRESSURE, 0, coord.pen_pressure, 0, 0);
+                if (coord.tilt_x && coord.tilt_y) {
+                        input_set_abs_params(dev, ABS_TILT_X, 0, coord.tilt_x, 0, 0);
+                        input_set_abs_params(dev, ABS_TILT_Y, 0, coord.tilt_y, 0, 0);
+                }
+        }
 
+        /* Touch enabled? */
         error = w8001_command(w8001, W8001_CMD_TOUCHQUERY, true);
-        if (!error) {
+
+        /*
+         * Some non-touch devices may reply to the touch query. But their
+         * second byte is empty, which indicates touch is not supported.
+         */
+        if (!error && w8001->response[1]) {
                 struct w8001_touch_query touch;
 
                 parse_touchquery(w8001->response, &touch);
 
+                input_set_abs_params(dev, ABS_X, 0, touch.x, 0, 0);
+                input_set_abs_params(dev, ABS_Y, 0, touch.y, 0, 0);
+                __set_bit(BTN_TOOL_FINGER, dev->keybit);
+
                 switch (touch.sensor_id) {
                 case 0:
                 case 2:
@@ -375,10 +399,6 @@ static int w8001_connect(struct serio *serio, struct serio_driver *drv)
 
         input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
         __set_bit(BTN_TOUCH, input_dev->keybit);
-        __set_bit(BTN_TOOL_PEN, input_dev->keybit);
-        __set_bit(BTN_TOOL_RUBBER, input_dev->keybit);
-        __set_bit(BTN_STYLUS, input_dev->keybit);
-        __set_bit(BTN_STYLUS2, input_dev->keybit);
 
         serio_set_drvdata(serio, w8001);
         err = serio_open(serio, drv);