Re: [PATCH v3 2/2] iio: adc: Add TI ADS1100 and ADS1000

[Lars-Peter Clausen]

On 3/1/23 23:49, Mike Looijmans wrote:
> > ...
> > ...
> >
> > > +static int ads1100_runtime_suspend(struct device *dev)
> > > +{
> > > +    struct iio_dev *indio_dev = 
> > > i2c_get_clientdata(to_i2c_client(dev));
> > > +    struct ads1100_data *data = iio_priv(indio_dev);
> > > +
> > > +    ads1100_set_config_bits(data, ADS1100_CFG_SC, ADS1100_SINGLESHOT);
> > > +    regulator_disable(data->reg_vdd);
> > Wrong devm / non-devm ordering.
>
> Don't understand your remark, can you explain further please?
>
> devm / non-devm ordering would be related to the "probe" function. As 
> far as I can tell, I'm not allocating resources after the devm calls. 
> And the "remove" is empty.

Strictly speaking we need to unregister the IIO device before disabling 
the regulator, otherwise there is a small window where the IIO device 
still exists, but doesn't work anymore. This is a very theoretical 
scenario though.

You are lucky :) There is a new function 
`devm_regulator_get_enable()`[1], which will manage the 
regulator_disable() for you. Using that will also reduce the boilerplate 
in `probe()` a bit

- Lars

[1] https://lwn.net/Articles/904383/