Re: [PATCH v3] iio: adc: Add support for TI ADC108S102 and ADC128S102

[Jan Kiszka <jan.kiszka@siemens.com>]

On 2017-05-05 11:40, Mika Westerberg wrote:
> On Fri, May 05, 2017 at 08:31:32AM +0200, Jan Kiszka wrote:
>> +static int adc108s102_probe(struct spi_device *spi)
>> +{
>> +	struct adc108s102_state *st;
>> +	struct iio_dev *indio_dev;
>> +	int ret;
>> +
>> +	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
>> +	if (!indio_dev)
>> +		return -ENOMEM;
>> +
>> +	st = iio_priv(indio_dev);
>> +
>> +	if (ACPI_COMPANION(&spi->dev)) {
>> +		st->reg = NULL;
>> +		ret = device_property_read_u32(&spi->dev, "va-millivolt",
>> +					    &st->va_millivolt);
> 
> Please try to avoid things like this for now. You can just hard code the
> voltage now and we can think how to solve this in ACPI if there will be
> an actual user needing anything else than the voltage you are using on
> your board.

OK, so I will set a static 5V in case of ACPI. Fine as well.

> 
>> +		if (ret < 0) {
>> +			dev_err(&spi->dev,
>> +				"Missing va-millivolt device property\n");
>> +			return -ENODEV;
>> +		}
>> +	} else {
>> +		st->reg = devm_regulator_get(&spi->dev, "vref");
>> +		if (IS_ERR(st->reg))
>> +			return PTR_ERR(st->reg);
> 
> This should be an optional regulator and in case of ACPI you just don't
> have it.

It's mandatory for this DT case, so I will not change that.

Thanks,
Jan

> 
>> +
>> +		ret = regulator_enable(st->reg);
>> +		if (ret < 0) {
>> +			dev_err(&spi->dev, "Cannot enable vref regulator\n");
>> +			return ret;
>> +		}
>> +	}

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