Re: [PATCH v3 2/2] iio: dac: support the ad8460 Waveform DAC

[David Lechner]

On 9/9/24 3:22 AM, Tinaco, Mariel wrote:
> 
> 

...

>>> +	if (IS_ERR(state->regmap))
>>> +		return dev_err_probe(dev, PTR_ERR(state->regmap),
>>> +				     "Failed to initialize regmap");
>>> +
>>> +	state->sync_clk = devm_clk_get_enabled(dev, NULL);
>>> +	if (IS_ERR(state->sync_clk))
>>> +		return dev_err_probe(dev, PTR_ERR(state->sync_clk),
>>> +				     "Failed to get sync clk\n");
>>> +
>>> +	state->tmp_adc_channel = devm_iio_channel_get(dev, "ad8460-
>> tmp");
>>> +	if (IS_ERR_OR_NULL(state->tmp_adc_channel)) {
>>> +		indio_dev->channels = ad8460_channels;
>>> +		indio_dev->num_channels = ARRAY_SIZE(ad8460_channels);
>>> +	} else {
>>> +		indio_dev->channels = ad8460_channels_with_tmp_adc;
>>> +		indio_dev->num_channels =
>> ARRAY_SIZE(ad8460_channels_with_tmp_adc);
>>> +	}
>>> +
>> Add and enable the various other supplies. They are probably always on in
>> which case the regulator framework will work it's magic to avoid use having to
>> care that they aren't in the dts.
> 
> If the other supplies are added, do they need to be tied up as well to the
> Private structure just like ref_1p2v? Or do I just apply the 
> devm_regulator_get_enable_read_voltage to it?
> 
> ret = devm_regulator_get_enable_read_voltage(&client->dev, "vdd");
> If (ret < 0 && ret != -ENODEV)
> 	return dev_err_probe(ltc2309->dev, ret,
> 				"failed to get vref voltage\n");
> 

For supplies that just supply power, we usually don't worry
about the voltage, so just use devm_regulator_get_enable().
Or if there are lots of supplies, you can use
devm_regulator_bulk_get_enable() to do them all at once.

They don't need to be added to the private structure.

Also, lots of chips have to have supplies turned on in a
certain order. This one is no exception, so be sure to
have a look at the "POWER SUPPLY SEQUENCING" section in
the datasheet to make sure the driver turns things on in
the right order.