Re: [PATCH v2 07/16] iio: adc: sun4i-gpadc-iio: rework: support nvmem calibration data

[Philipp Rossak]

> > > >    	/* prevents concurrent reads of temperature and ADC */
> > > >    	struct mutex			mutex;
> > > >    	struct thermal_zone_device	*tzd;
> > > > @@ -561,6 +569,9 @@ static int sun4i_gpadc_probe_dt(struct platform_device *pdev,
> > > >    	struct resource *mem;
> > > >    	void __iomem *base;
> > > >    	int ret;
> > > > +	struct nvmem_cell *cell;
> > > > +	ssize_t cell_size;
> > > > +	u64 *cell_data;
> > > >    	info->data = of_device_get_match_data(&pdev->dev);
> > > >    	if (!info->data)
> > > > @@ -575,6 +586,39 @@ static int sun4i_gpadc_probe_dt(struct platform_device *pdev,
> > > >    	if (IS_ERR(base))
> > > >    		return PTR_ERR(base);
> > > > +	info->has_calibration_data[0] = false;
> > > > +	info->has_calibration_data[1] = false;
> > > > +
> > > > +	if (!info->data->supports_nvmem)
> > > > +		goto no_nvmem;
> > > > +
> > > > +	cell = nvmem_cell_get(&pdev->dev, "calibration");
> > > > +	if (IS_ERR(cell)) {
> > > > +		if (PTR_ERR(cell) == -EPROBE_DEFER)
> > > > +			return PTR_ERR(cell);
> > > > +		goto no_nvmem;
> > >
> > > goto considered evil ? :)
> >
> > this was a suggestion from Jonatan in version one, to make the code better
> > readable.
>
> Isn't
>
> if (info->data->supports_nvmem && IS_ERR(cell = nvmem_cell_get()))
>
> pretty much the same thing?
>
> Maxime
I would say :

if (info->data->supports_nvmem && !IS_ERR(cell = nvmem_cell_get())) is

the same.
This would require an else if statement like this:

else if (info->data->supports_nvmem && PTR_ERR(cell) == -EPROBE_DEFER)
		return PTR_ERR(cell);

to avoid errors if the thermal sensor is probed before the sid driver.

Philipp