mfd: cros_ec: Register cros_ec_lid_angle driver when presented

Register driver when EC indicates has precise lid angle calculation code
running.
Fix incorrect extra resource allocation in cros_ec_sensors_register().

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

drivers/mfd/cros_ec_dev.c

@@ -297,13 +297,15 @@ static void cros_ec_sensors_register(struct cros_ec_dev *ec)
 
 	resp = (struct ec_response_motion_sense *)msg->data;
 	sensor_num = resp->dump.sensor_count;
-	/* Allocate 1 extra sensors in FIFO are needed */
-	sensor_cells = kcalloc(sensor_num + 1, sizeof(struct mfd_cell),
+	/*
+	 * Allocate 2 extra sensors if lid angle sensor and/or FIFO are needed.
+	 */
+	sensor_cells = kcalloc(sensor_num + 2, sizeof(struct mfd_cell),
 			       GFP_KERNEL);
 	if (sensor_cells == NULL)
 		goto error;
 
-	sensor_platforms = kcalloc(sensor_num + 1,
+	sensor_platforms = kcalloc(sensor_num,
 				   sizeof(struct cros_ec_sensor_platform),
 				   GFP_KERNEL);
 	if (sensor_platforms == NULL)
@@ -363,6 +365,11 @@ static void cros_ec_sensors_register(struct cros_ec_dev *ec)
 		sensor_cells[id].name = "cros-ec-ring";
 		id++;
 	}
+	if (cros_ec_check_features(ec,
+				EC_FEATURE_REFINED_TABLET_MODE_HYSTERESIS)) {
+		sensor_cells[id].name = "cros-ec-lid-angle";
+		id++;
+	}
 
 	ret = mfd_add_devices(ec->dev, 0, sensor_cells, id,
 			      NULL, 0, NULL);