Re: [RFC PATCH v1 1/4] iio: adc: Add Allwinner D1/T113s/R329 SoCs GPADC

[Andy Shevchenko]

On Wed, May 24, 2023 at 11:01:05AM +0100, Andre Przywara wrote:
> On Wed, 24 May 2023 11:27:30 +0300
> Maxim Kiselev <bigunclemax@xxxxxxxxx> wrote:

...

> > +static const struct regmap_config sun20i_gpadc_regmap_config = {
> > +	.reg_bits = 32,
> > +	.val_bits = 32,
> > +	.reg_stride = 4,
> > +	.fast_io = true,
> > +};
> 
> Is there any particular reason you chose a regmap to model this here?
> Isn't that just straight-forward MMIO, which we could just drive using
> readl()/writel()?

Even though regmap adds a few nice features that might be used.
For example, locking. But I dunno if this driver actually uses it
OR uses it correctly.

...

> > +	config = of_device_get_match_data(&pdev->dev);

Please, avoid using OF-centric APIs in the new IIO drivers.

	config = device_get_match_data(&pdev->dev);

should suffice.

> > +	if (!config)
> > +		return -ENODEV;

...

> > +	irq = platform_get_irq(pdev, 0);
> > +	if (irq < 0)
> > +		return dev_err_probe(&pdev->dev, irq, "failed to get irq\n");

We should not repeat the message that printed by platform core.

...

> > +	ret = devm_request_irq(&pdev->dev, irq, sun20i_gpadc_irq_handler,
> > +			       0, dev_name(&pdev->dev), info);

You can simplify your life with

	struct device *dev = &pdev->dev;

at the definition block of the function.

> > +	if (ret < 0)
> > +		return dev_err_probe(&pdev->dev, ret,
> > +				     "failed requesting irq %d\n", irq);

...

> > +		.data = &sun20i_d1_gpadc_channels[1]

Also, leave comma here.

...

> > +		.data = &sun50i_r329_gpadc_channels[2]

Same as above.

-- 
With Best Regards,
Andy Shevchenko