staging: iio: adis16240: Use Managed device functions

Use the adis managed device functions to setup the buffer and the trigger.
The ultimate goal will be to completely drop the non devm version from
the lib.

Since we are here, drop the `.remove` callback by further using devm
functions.
Signed-off-by: Nuno Sá <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20200915120258.161587-10-nuno.sa@analog.comSigned-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/staging/iio/accel/adis16240.c

@@ -415,35 +415,17 @@ static int adis16240_probe(struct spi_device *spi)
 	ret = adis_init(st, indio_dev, spi, &adis16240_data);
 	if (ret)
 		return ret;
-	ret = adis_setup_buffer_and_trigger(st, indio_dev, NULL);
+	ret = devm_adis_setup_buffer_and_trigger(st, indio_dev, NULL);
 	if (ret)
 		return ret;
 
 	/* Get the device into a sane initial state */
 	ret = adis_initial_startup(st);
 	if (ret)
-		goto error_cleanup_buffer_trigger;
-	ret = iio_device_register(indio_dev);
-	if (ret)
-		goto error_cleanup_buffer_trigger;
-	return 0;
-
-error_cleanup_buffer_trigger:
-	adis_cleanup_buffer_and_trigger(st, indio_dev);
 		return ret;
-}
-
-static int adis16240_remove(struct spi_device *spi)
-{
-	struct iio_dev *indio_dev = spi_get_drvdata(spi);
-	struct adis *st = iio_priv(indio_dev);
 
-	iio_device_unregister(indio_dev);
-	adis_cleanup_buffer_and_trigger(st, indio_dev);
-
-	return 0;
+	return devm_iio_device_register(&spi->dev, indio_dev);
 }
-
 static const struct of_device_id adis16240_of_match[] = {
 	{ .compatible = "adi,adis16240" },
 	{ },
@@ -456,7 +438,6 @@ static struct spi_driver adis16240_driver = {
 		.of_match_table = adis16240_of_match,
 	},
 	.probe = adis16240_probe,
-	.remove = adis16240_remove,
 };
 module_spi_driver(adis16240_driver);