iio: mxs-lradc: simplify TS registration

This patch simplifies the TS registration of mxs-lradc by
using devm_input_allocate_device.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: Marek Vasut <marex@denx.de>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

drivers/iio/adc/mxs-lradc.c

@@ -1120,18 +1120,16 @@ static int mxs_lradc_ts_register(struct mxs_lradc *lradc)
 {
 	struct input_dev *input;
 	struct device *dev = lradc->dev;
-	int ret;
 
 	if (!lradc->use_touchscreen)
 		return 0;
 
-	input = input_allocate_device();
+	input = devm_input_allocate_device(dev);
 	if (!input)
 		return -ENOMEM;
 
 	input->name = DRIVER_NAME;
 	input->id.bustype = BUS_HOST;
-	input->dev.parent = dev;
 	input->open = mxs_lradc_ts_open;
 	input->close = mxs_lradc_ts_close;
 
@@ -1146,11 +1144,8 @@ static int mxs_lradc_ts_register(struct mxs_lradc *lradc)
 
 	lradc->ts_input = input;
 	input_set_drvdata(input, lradc);
-	ret = input_register_device(input);
-	if (ret)
-		input_free_device(lradc->ts_input);
 
-	return ret;
+	return input_register_device(input);
 }
 
 static void mxs_lradc_ts_unregister(struct mxs_lradc *lradc)
@@ -1159,7 +1154,6 @@ static void mxs_lradc_ts_unregister(struct mxs_lradc *lradc)
 		return;
 
 	mxs_lradc_disable_ts(lradc);
-	input_unregister_device(lradc->ts_input);
 }
 
 /*