On 6/1/24 8:01 AM, Jonathan Cameron wrote:
> On Fri, 31 May 2024 16:19:36 -0500
> David Lechner <dlechner@xxxxxxxxxxxx> wrote:
>
>> This makes use of the new devm_regulator_get_enable_read_voltage()
>> function to reduce boilerplate code.
>>
>> Signed-off-by: David Lechner <dlechner@xxxxxxxxxxxx>
> A possible corner case inline.
>
> Patches 2-4 lgtm.
>> ---
>> drivers/iio/adc/ad7944.c | 62 +++++++++++++++---------------------------------
>> 1 file changed, 19 insertions(+), 43 deletions(-)
>>
>> diff --git a/drivers/iio/adc/ad7944.c b/drivers/iio/adc/ad7944.c
>> index e2cb64cef476..42bbcb904778 100644
>> --- a/drivers/iio/adc/ad7944.c
>> +++ b/drivers/iio/adc/ad7944.c
>> @@ -464,23 +464,16 @@ static const char * const ad7944_power_supplies[] = {
>> "avdd", "dvdd", "bvdd", "vio"
>> };
>>
>> -static void ad7944_ref_disable(void *ref)
>> -{
>> - regulator_disable(ref);
>> -}
>> -
>> static int ad7944_probe(struct spi_device *spi)
>> {
>> const struct ad7944_chip_info *chip_info;
>> struct device *dev = &spi->dev;
>> struct iio_dev *indio_dev;
>> struct ad7944_adc *adc;
>> - bool have_refin = false;
>> - struct regulator *ref;
>> struct iio_chan_spec *chain_chan;
>> unsigned long *chain_scan_masks;
>> u32 n_chain_dev;
>> - int ret;
>> + int ret, ref_mv, refin_mv;
>>
>> indio_dev = devm_iio_device_alloc(dev, sizeof(*adc));
>> if (!indio_dev)
>> @@ -531,47 +524,30 @@ static int ad7944_probe(struct spi_device *spi)
>> * - external reference: REF is connected, REFIN is not connected
>> */
>>
>> - ref = devm_regulator_get_optional(dev, "ref");
>> - if (IS_ERR(ref)) {
>> - if (PTR_ERR(ref) != -ENODEV)
>> - return dev_err_probe(dev, PTR_ERR(ref),
>> - "failed to get REF supply\n");
>> -
>> - ref = NULL;
>> - }
>> + ret = devm_regulator_get_enable_read_voltage(dev, "ref");
>> + if (ret == -ENODEV)
>> + ref_mv = 0;
>> + else if (ret < 0)
>> + return dev_err_probe(dev, ret, "failed to get REF voltage\n");
>> + else
>> + ref_mv = ret / 1000;
>>
>> - ret = devm_regulator_get_enable_optional(dev, "refin");
>> - if (ret == 0)
>> - have_refin = true;
>> - else if (ret != -ENODEV)
>> - return dev_err_probe(dev, ret,
>> - "failed to get and enable REFIN supply\n");
>> + ret = devm_regulator_get_enable_read_voltage(dev, "refin");
>> + if (ret == -ENODEV)
>> + refin_mv = 0;
>> + else if (ret < 0)
>> + return dev_err_probe(dev, ret, "failed to get REFIN voltage\n");
>> + else
>> + refin_mv = ret / 1000;
> How does refin_mv get used? Previously we never queried it's voltage (I assume
> because it supplies an internal reference?
>
> Are there any regulators that are real enough to enable but for which a voltage
> can't be queried? I think fixed regulators with gpio control are in this
> category...
>
Hmm... don't remember why I did it that way (was a while ago). I will bring
back the have_refin flag instead.
