Input: atmel_mxt_ts - use T9 reportid range to init number of mt slots

Atmel mxt devices can report one finger for each T9 reportid.
Therefore, this range can be used to report the max number of MT-B slots
to userspace instead of assuming a fixed 10.

Note that mxt_initialized() must complete early, since the input_dev
properties now depend on values in the object table.
Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
Signed-off-by: Henrik Rydberg <rydberg@euromail.se>

drivers/input/touchscreen/atmel_mxt_ts.c

@@ -212,8 +212,6 @@
 /* Touchscreen absolute values */
 #define MXT_MAX_AREA		0xff
 
-#define MXT_MAX_FINGER		10
-
 struct mxt_info {
 	u8 family_id;
 	u8 variant_id;
@@ -1086,6 +1084,7 @@ static int __devinit mxt_probe(struct i2c_client *client,
 	struct mxt_data *data;
 	struct input_dev *input_dev;
 	int error;
+	unsigned int num_mt_slots;
 
 	if (!pdata)
 		return -EINVAL;
@@ -1115,6 +1114,10 @@ static int __devinit mxt_probe(struct i2c_client *client,
 
 	mxt_calc_resolution(data);
 
+	error = mxt_initialize(data);
+	if (error)
+		goto err_free_mem;
+
 	__set_bit(EV_ABS, input_dev->evbit);
 	__set_bit(EV_KEY, input_dev->evbit);
 	__set_bit(BTN_TOUCH, input_dev->keybit);
@@ -1128,9 +1131,10 @@ static int __devinit mxt_probe(struct i2c_client *client,
 			     0, 255, 0, 0);
 
 	/* For multi touch */
-	error = input_mt_init_slots(input_dev, MXT_MAX_FINGER);
+	num_mt_slots = data->T9_reportid_max - data->T9_reportid_min + 1;
+	error = input_mt_init_slots(input_dev, num_mt_slots);
 	if (error)
-		goto err_free_mem;
+		goto err_free_object;
 	input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR,
 			     0, MXT_MAX_AREA, 0, 0);
 	input_set_abs_params(input_dev, ABS_MT_POSITION_X,
@@ -1143,10 +1147,6 @@ static int __devinit mxt_probe(struct i2c_client *client,
 	input_set_drvdata(input_dev, data);
 	i2c_set_clientdata(client, data);
 
-	error = mxt_initialize(data);
-	if (error)
-		goto err_free_mem;
-
 	error = request_threaded_irq(client->irq, NULL, mxt_interrupt,
 			pdata->irqflags, client->name, data);
 	if (error) {