iio: potentiometer: max5481: convert probe to device-managed

The change converts the probe function to use the
devm_iio_device_register() function.

Before calling that, we need to register an action to store the wiper back
to non-volatile memory when the device is de-registered.

We don't need to do this if the probe fails, because the only place where
the probe can fail now is devm_iio_device_register() and that shouldn't
create an IIO device (for userspace to poke at) if it fails.

Signed-off-by: Alexandru Ardelean <aardelean@deviqon.com>
Link: https://lore.kernel.org/r/20210624080641.9953-1-aardelean@deviqon.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This commit is contained in:
Alexandru Ardelean 2021-06-24 11:06:41 +03:00 committed by Jonathan Cameron
parent c359a80ca2
commit d272e0ab5f

View File

@ -125,6 +125,11 @@ static const struct of_device_id max5481_match[] = {
};
MODULE_DEVICE_TABLE(of, max5481_match);
static void max5481_wiper_save(void *data)
{
max5481_write_cmd(data, MAX5481_COPY_AB_TO_NV, 0);
}
static int max5481_probe(struct spi_device *spi)
{
struct iio_dev *indio_dev;
@ -136,7 +141,6 @@ static int max5481_probe(struct spi_device *spi)
if (!indio_dev)
return -ENOMEM;
spi_set_drvdata(spi, indio_dev);
data = iio_priv(indio_dev);
data->spi = spi;
@ -158,18 +162,11 @@ static int max5481_probe(struct spi_device *spi)
if (ret < 0)
return ret;
return iio_device_register(indio_dev);
}
ret = devm_add_action(&spi->dev, max5481_wiper_save, data);
if (ret < 0)
return ret;
static int max5481_remove(struct spi_device *spi)
{
struct iio_dev *indio_dev = spi_get_drvdata(spi);
struct max5481_data *data = iio_priv(indio_dev);
iio_device_unregister(indio_dev);
/* save wiper reg to NV reg */
return max5481_write_cmd(data, MAX5481_COPY_AB_TO_NV, 0);
return devm_iio_device_register(&spi->dev, indio_dev);
}
static const struct spi_device_id max5481_id_table[] = {
@ -187,7 +184,6 @@ static struct spi_driver max5481_driver = {
.of_match_table = max5481_match,
},
.probe = max5481_probe,
.remove = max5481_remove,
.id_table = max5481_id_table,
};