diff mbox series

[5/5] iio: adc: ad7944: use devm_regulator_get_enable_read_voltage

Message ID 20240531-iio-adc-ref-supply-refactor-v1-5-4b313c0615ad@baylibre.com (mailing list archive)
State Changes Requested
Headers show
Series iio: adc: use devm_regulator_get_enable_read_voltage round 1 | expand

Commit Message

David Lechner May 31, 2024, 9:19 p.m. UTC 
This makes use of the new devm_regulator_get_enable_read_voltage()
function to reduce boilerplate code.

Signed-off-by: David Lechner <dlechner@baylibre.com>
---
 drivers/iio/adc/ad7944.c | 62 +++++++++++++++---------------------------------
 1 file changed, 19 insertions(+), 43 deletions(-)

Comments

Jonathan Cameron June 1, 2024, 1:01 p.m. UTC | #1 
On Fri, 31 May 2024 16:19:36 -0500
David Lechner <dlechner@baylibre.com> wrote:

> This makes use of the new devm_regulator_get_enable_read_voltage()
> function to reduce boilerplate code.
> 
> Signed-off-by: David Lechner <dlechner@baylibre.com>
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...

>  
> -	if (have_refin && ref)
> +	if (ref_mv && refin_mv)
>  		return dev_err_probe(dev, -EINVAL,
>  				     "cannot have both refin and ref supplies\n");
>  
> -	if (ref) {
> -		ret = regulator_enable(ref);
> -		if (ret)
> -			return dev_err_probe(dev, ret,
> -					     "failed to enable REF supply\n");
> -
> -		ret = devm_add_action_or_reset(dev, ad7944_ref_disable, ref);
> -		if (ret)
> -			return ret;
> -
> -		ret = regulator_get_voltage(ref);
> -		if (ret < 0)
> -			return dev_err_probe(dev, ret,
> -					     "failed to get REF voltage\n");
> -
> -		/* external reference */
> -		adc->ref_mv = ret / 1000;
> -	} else {
> -		/* internal reference */
> +	if (ref_mv)
> +		adc->ref_mv = ref_mv;
> +	else
>  		adc->ref_mv = AD7944_INTERNAL_REF_MV;
> -	}
>  
>  	adc->cnv = devm_gpiod_get_optional(dev, "cnv", GPIOD_OUT_LOW);
>  	if (IS_ERR(adc->cnv))
>
David Lechner June 3, 2024, 1:38 p.m. UTC | #2 
On 6/1/24 8:01 AM, Jonathan Cameron wrote:
> On Fri, 31 May 2024 16:19:36 -0500
> David Lechner <dlechner@baylibre.com> wrote:
> 
>> This makes use of the new devm_regulator_get_enable_read_voltage()
>> function to reduce boilerplate code.
>>
>> Signed-off-by: David Lechner <dlechner@baylibre.com>
> 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.
diff mbox series

Patch

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;
 
-	if (have_refin && ref)
+	if (ref_mv && refin_mv)
 		return dev_err_probe(dev, -EINVAL,
 				     "cannot have both refin and ref supplies\n");
 
-	if (ref) {
-		ret = regulator_enable(ref);
-		if (ret)
-			return dev_err_probe(dev, ret,
-					     "failed to enable REF supply\n");
-
-		ret = devm_add_action_or_reset(dev, ad7944_ref_disable, ref);
-		if (ret)
-			return ret;
-
-		ret = regulator_get_voltage(ref);
-		if (ret < 0)
-			return dev_err_probe(dev, ret,
-					     "failed to get REF voltage\n");
-
-		/* external reference */
-		adc->ref_mv = ret / 1000;
-	} else {
-		/* internal reference */
+	if (ref_mv)
+		adc->ref_mv = ref_mv;
+	else
 		adc->ref_mv = AD7944_INTERNAL_REF_MV;
-	}
 
 	adc->cnv = devm_gpiod_get_optional(dev, "cnv", GPIOD_OUT_LOW);
 	if (IS_ERR(adc->cnv))