diff mbox series

[v5,01/11] staging: iio: ad7780: add gain & filter gpio support

Message ID 2687836c5b442990ee50d4efe787a3927c750bbc.1552700652.git.renatogeh@gmail.com (mailing list archive)
State New, archived
Headers show
Series staging: iio: ad7780: move out of staging | expand

Commit Message

Renato Lui Geh March 16, 2019, 2:12 a.m. UTC
Previously, the AD7780 driver only supported gpio for the 'powerdown'
pin. This commit adds suppport for the 'gain' and 'filter' pin.

Signed-off-by: Renato Lui Geh <renatogeh@gmail.com>
Signed-off-by: Giuliano Belinassi <giuliano.belinassi@usp.br>
Co-developed-by: Giuliano Belinassi <giuliano.belinassi@usp.br>
---
Changes in v3:
 - Renamed ad7780_chip_info's filter to odr
 - Renamed ad778x_filter to ad778x_odr_avail
 - Changed vref variable from unsigned int to unsigned long long to avoid
   overflow
 - Removed unnecessary AD_SD_CHANNEL macro
Changes in v4:
 - Removed useless macro
 - Added default case for switch to suppress warning
 - Removed chunks belonging to filter reading, adding these as a
   patch for itself
Changes in v5:
 - ad778x_odr_avail moved to filter patch
 - Split gain reading to its own patch
 - Init GPIOs in a separate function

 drivers/staging/iio/adc/ad7780.c | 114 ++++++++++++++++++++++++++-----
 1 file changed, 96 insertions(+), 18 deletions(-)

Comments

Jonathan Cameron March 16, 2019, 5:46 p.m. UTC | #1
On Fri, 15 Mar 2019 23:12:27 -0300
Renato Lui Geh <renatogeh@gmail.com> wrote:

> Previously, the AD7780 driver only supported gpio for the 'powerdown'
> pin. This commit adds suppport for the 'gain' and 'filter' pin.
> 
> Signed-off-by: Renato Lui Geh <renatogeh@gmail.com>
> Signed-off-by: Giuliano Belinassi <giuliano.belinassi@usp.br>
> Co-developed-by: Giuliano Belinassi <giuliano.belinassi@usp.br>
Something a little odd happened when trying to use git am on this,
but patch was happy so I did it that way. Please give it a quick
sanity check once I push the tree out incase we have a real problem.

Applied to the togreg branch of iio.git to be shortly pushed out
as testing for the autobuilders to play with it.

Thanks,

Jonathan

> ---
> Changes in v3:
>  - Renamed ad7780_chip_info's filter to odr
>  - Renamed ad778x_filter to ad778x_odr_avail
>  - Changed vref variable from unsigned int to unsigned long long to avoid
>    overflow
>  - Removed unnecessary AD_SD_CHANNEL macro
> Changes in v4:
>  - Removed useless macro
>  - Added default case for switch to suppress warning
>  - Removed chunks belonging to filter reading, adding these as a
>    patch for itself
> Changes in v5:
>  - ad778x_odr_avail moved to filter patch
>  - Split gain reading to its own patch
>  - Init GPIOs in a separate function
> 
>  drivers/staging/iio/adc/ad7780.c | 114 ++++++++++++++++++++++++++-----
>  1 file changed, 96 insertions(+), 18 deletions(-)
> 
> diff --git a/drivers/staging/iio/adc/ad7780.c b/drivers/staging/iio/adc/ad7780.c
> index c4a85789c2db..07e5e35c92a3 100644
> --- a/drivers/staging/iio/adc/ad7780.c
> +++ b/drivers/staging/iio/adc/ad7780.c
> @@ -39,6 +39,9 @@
>  #define AD7170_PATTERN		(AD7780_PAT0 | AD7170_PAT2)
>  #define AD7170_PATTERN_MASK	(AD7780_PAT0 | AD7780_PAT1 | AD7170_PAT2)
>  
> +#define AD7780_GAIN_MIDPOINT	64
> +#define AD7780_FILTER_MIDPOINT	13350
> +
>  struct ad7780_chip_info {
>  	struct iio_chan_spec	channel;
>  	unsigned int		pattern_mask;
> @@ -50,7 +53,10 @@ struct ad7780_state {
>  	const struct ad7780_chip_info	*chip_info;
>  	struct regulator		*reg;
>  	struct gpio_desc		*powerdown_gpio;
> -	unsigned int	gain;
> +	struct gpio_desc		*gain_gpio;
> +	struct gpio_desc		*filter_gpio;
> +	unsigned int			gain;
> +	unsigned int			int_vref_mv;
>  
>  	struct ad_sigma_delta sd;
>  };
> @@ -104,8 +110,10 @@ static int ad7780_read_raw(struct iio_dev *indio_dev,
>  		voltage_uv = regulator_get_voltage(st->reg);
>  		if (voltage_uv < 0)
>  			return voltage_uv;
> -		*val = (voltage_uv / 1000) * st->gain;
> +		voltage_uv /= 1000;
> +		*val = voltage_uv * st->gain;
>  		*val2 = chan->scan_type.realbits - 1;
> +		st->int_vref_mv = voltage_uv;
>  		return IIO_VAL_FRACTIONAL_LOG2;
>  	case IIO_CHAN_INFO_OFFSET:
>  		*val = -(1 << (chan->scan_type.realbits - 1));
> @@ -115,6 +123,50 @@ static int ad7780_read_raw(struct iio_dev *indio_dev,
>  	return -EINVAL;
>  }
>  
> +static int ad7780_write_raw(struct iio_dev *indio_dev,
> +			    struct iio_chan_spec const *chan,
> +			    int val,
> +			    int val2,
> +			    long m)
> +{
> +	struct ad7780_state *st = iio_priv(indio_dev);
> +	const struct ad7780_chip_info *chip_info = st->chip_info;
> +	unsigned long long vref;
> +	unsigned int full_scale, gain;
> +
> +	if (!chip_info->is_ad778x)
> +		return -EINVAL;
> +
> +	switch (m) {
> +	case IIO_CHAN_INFO_SCALE:
> +		if (val != 0)
> +			return -EINVAL;
> +
> +		vref = st->int_vref_mv * 1000000LL;
> +		full_scale = 1 << (chip_info->channel.scan_type.realbits - 1);
> +		gain = DIV_ROUND_CLOSEST(vref, full_scale);
> +		gain = DIV_ROUND_CLOSEST(gain, val2);
> +		st->gain = gain;
> +		if (gain < AD7780_GAIN_MIDPOINT)
> +			gain = 0;
> +		else
> +			gain = 1;
> +		gpiod_set_value(st->gain_gpio, gain);
> +		break;
> +	case IIO_CHAN_INFO_SAMP_FREQ:
> +		if (1000*val + val2/1000 < AD7780_FILTER_MIDPOINT)
> +			val = 0;
> +		else
> +			val = 1;
> +		gpiod_set_value(st->filter_gpio, val);
> +		break;
> +	default:
> +		break;
> +	}
> +
> +	return 0;
> +}
> +
>  static int ad7780_postprocess_sample(struct ad_sigma_delta *sigma_delta,
>  				     unsigned int raw_sample)
>  {
> @@ -125,13 +177,6 @@ static int ad7780_postprocess_sample(struct ad_sigma_delta *sigma_delta,
>  	    ((raw_sample & chip_info->pattern_mask) != chip_info->pattern))
>  		return -EIO;
>  
> -	if (chip_info->is_ad778x) {
> -		if (raw_sample & AD7780_GAIN)
> -			st->gain = 1;
> -		else
> -			st->gain = 128;
> -	}
> -
>  	return 0;
>  }
>  
> @@ -173,8 +218,47 @@ static const struct ad7780_chip_info ad7780_chip_info_tbl[] = {
>  
>  static const struct iio_info ad7780_info = {
>  	.read_raw = ad7780_read_raw,
> +	.write_raw = ad7780_write_raw,
>  };
>  
> +static int ad7780_init_gpios(struct device *dev, struct ad7780_state *st)
> +{
> +	int ret;
> +
> +	st->powerdown_gpio = devm_gpiod_get_optional(dev,
> +						     "powerdown",
> +						     GPIOD_OUT_LOW);
> +	if (IS_ERR(st->powerdown_gpio)) {
> +		ret = PTR_ERR(st->powerdown_gpio);
> +		dev_err(dev, "Failed to request powerdown GPIO: %d\n", ret);
> +		return ret;
> +	}
> +
> +	if (!st->chip_info->is_ad778x)
> +		return 0;
> +
nitpick: One blank line is always enough. More just reduces the amount of
code that can be seen at a time.

> +
> +	st->gain_gpio = devm_gpiod_get_optional(dev,
> +						"adi,gain",
> +						GPIOD_OUT_HIGH);
> +	if (IS_ERR(st->gain_gpio)) {
> +		ret = PTR_ERR(st->gain_gpio);
> +		dev_err(dev, "Failed to request gain GPIO: %d\n", ret);
> +		return ret;
> +	}
> +
> +	st->filter_gpio = devm_gpiod_get_optional(dev,
> +						  "adi,filter",
> +						  GPIOD_OUT_HIGH);
> +	if (IS_ERR(st->filter_gpio)) {
> +		ret = PTR_ERR(st->filter_gpio);
> +		dev_err(dev, "Failed to request filter GPIO: %d\n", ret);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
>  static int ad7780_probe(struct spi_device *spi)
>  {
>  	struct ad7780_state *st;
> @@ -212,15 +296,9 @@ static int ad7780_probe(struct spi_device *spi)
>  	indio_dev->num_channels = 1;
>  	indio_dev->info = &ad7780_info;
>  
> -	st->powerdown_gpio = devm_gpiod_get_optional(&spi->dev,
> -						     "powerdown",
> -						     GPIOD_OUT_LOW);
> -	if (IS_ERR(st->powerdown_gpio)) {
> -		ret = PTR_ERR(st->powerdown_gpio);
> -		dev_err(&spi->dev, "Failed to request powerdown GPIO: %d\n",
> -			ret);
> -		goto error_disable_reg;
> -	}
> +	ret = ad7780_init_gpios(&spi->dev, st);
> +	if (ret)
> +		goto error_cleanup_buffer_and_trigger;
>  
>  	ret = ad_sd_setup_buffer_and_trigger(indio_dev);
>  	if (ret)
Jonathan Cameron March 24, 2019, 11:06 a.m. UTC | #2
On Sat, 16 Mar 2019 17:46:40 +0000
Jonathan Cameron <jic23@kernel.org> wrote:

> On Fri, 15 Mar 2019 23:12:27 -0300
> Renato Lui Geh <renatogeh@gmail.com> wrote:
> 
> > Previously, the AD7780 driver only supported gpio for the 'powerdown'
> > pin. This commit adds suppport for the 'gain' and 'filter' pin.
> > 
> > Signed-off-by: Renato Lui Geh <renatogeh@gmail.com>
> > Signed-off-by: Giuliano Belinassi <giuliano.belinassi@usp.br>
> > Co-developed-by: Giuliano Belinassi <giuliano.belinassi@usp.br>  
> Something a little odd happened when trying to use git am on this,
> but patch was happy so I did it that way. Please give it a quick
> sanity check once I push the tree out incase we have a real problem.
> 
> Applied to the togreg branch of iio.git to be shortly pushed out
> as testing for the autobuilders to play with it.

Ah, we missed a 64 bit being divided below. Found by 0day.


> 
> Thanks,
> 
> Jonathan
> 
> > ---
> > Changes in v3:
> >  - Renamed ad7780_chip_info's filter to odr
> >  - Renamed ad778x_filter to ad778x_odr_avail
> >  - Changed vref variable from unsigned int to unsigned long long to avoid
> >    overflow
> >  - Removed unnecessary AD_SD_CHANNEL macro
> > Changes in v4:
> >  - Removed useless macro
> >  - Added default case for switch to suppress warning
> >  - Removed chunks belonging to filter reading, adding these as a
> >    patch for itself
> > Changes in v5:
> >  - ad778x_odr_avail moved to filter patch
> >  - Split gain reading to its own patch
> >  - Init GPIOs in a separate function
> > 
> >  drivers/staging/iio/adc/ad7780.c | 114 ++++++++++++++++++++++++++-----
> >  1 file changed, 96 insertions(+), 18 deletions(-)
> > 
> > diff --git a/drivers/staging/iio/adc/ad7780.c b/drivers/staging/iio/adc/ad7780.c
> > index c4a85789c2db..07e5e35c92a3 100644
> > --- a/drivers/staging/iio/adc/ad7780.c
> > +++ b/drivers/staging/iio/adc/ad7780.c
> > @@ -39,6 +39,9 @@
> >  #define AD7170_PATTERN		(AD7780_PAT0 | AD7170_PAT2)
> >  #define AD7170_PATTERN_MASK	(AD7780_PAT0 | AD7780_PAT1 | AD7170_PAT2)
> >  
> > +#define AD7780_GAIN_MIDPOINT	64
> > +#define AD7780_FILTER_MIDPOINT	13350
> > +
> >  struct ad7780_chip_info {
> >  	struct iio_chan_spec	channel;
> >  	unsigned int		pattern_mask;
> > @@ -50,7 +53,10 @@ struct ad7780_state {
> >  	const struct ad7780_chip_info	*chip_info;
> >  	struct regulator		*reg;
> >  	struct gpio_desc		*powerdown_gpio;
> > -	unsigned int	gain;
> > +	struct gpio_desc		*gain_gpio;
> > +	struct gpio_desc		*filter_gpio;
> > +	unsigned int			gain;
> > +	unsigned int			int_vref_mv;
> >  
> >  	struct ad_sigma_delta sd;
> >  };
> > @@ -104,8 +110,10 @@ static int ad7780_read_raw(struct iio_dev *indio_dev,
> >  		voltage_uv = regulator_get_voltage(st->reg);
> >  		if (voltage_uv < 0)
> >  			return voltage_uv;
> > -		*val = (voltage_uv / 1000) * st->gain;
> > +		voltage_uv /= 1000;
> > +		*val = voltage_uv * st->gain;
> >  		*val2 = chan->scan_type.realbits - 1;
> > +		st->int_vref_mv = voltage_uv;
> >  		return IIO_VAL_FRACTIONAL_LOG2;
> >  	case IIO_CHAN_INFO_OFFSET:
> >  		*val = -(1 << (chan->scan_type.realbits - 1));
> > @@ -115,6 +123,50 @@ static int ad7780_read_raw(struct iio_dev *indio_dev,
> >  	return -EINVAL;
> >  }
> >  
> > +static int ad7780_write_raw(struct iio_dev *indio_dev,
> > +			    struct iio_chan_spec const *chan,
> > +			    int val,
> > +			    int val2,
> > +			    long m)
> > +{
> > +	struct ad7780_state *st = iio_priv(indio_dev);
> > +	const struct ad7780_chip_info *chip_info = st->chip_info;
> > +	unsigned long long vref;
> > +	unsigned int full_scale, gain;
> > +
> > +	if (!chip_info->is_ad778x)
> > +		return -EINVAL;
> > +
> > +	switch (m) {
> > +	case IIO_CHAN_INFO_SCALE:
> > +		if (val != 0)
> > +			return -EINVAL;
> > +
> > +		vref = st->int_vref_mv * 1000000LL;
> > +		full_scale = 1 << (chip_info->channel.scan_type.realbits - 1);
> > +		gain = DIV_ROUND_CLOSEST(vref, full_scale);

DIV_ROUND_CLOSEST_ULL needed as vref is long long.

I'll fix up.

Jonathan

> > +		gain = DIV_ROUND_CLOSEST(gain, val2);
> > +		st->gain = gain;
> > +		if (gain < AD7780_GAIN_MIDPOINT)
> > +			gain = 0;
> > +		else
> > +			gain = 1;
> > +		gpiod_set_value(st->gain_gpio, gain);
> > +		break;
> > +	case IIO_CHAN_INFO_SAMP_FREQ:
> > +		if (1000*val + val2/1000 < AD7780_FILTER_MIDPOINT)
> > +			val = 0;
> > +		else
> > +			val = 1;
> > +		gpiod_set_value(st->filter_gpio, val);
> > +		break;
> > +	default:
> > +		break;
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> >  static int ad7780_postprocess_sample(struct ad_sigma_delta *sigma_delta,
> >  				     unsigned int raw_sample)
> >  {
> > @@ -125,13 +177,6 @@ static int ad7780_postprocess_sample(struct ad_sigma_delta *sigma_delta,
> >  	    ((raw_sample & chip_info->pattern_mask) != chip_info->pattern))
> >  		return -EIO;
> >  
> > -	if (chip_info->is_ad778x) {
> > -		if (raw_sample & AD7780_GAIN)
> > -			st->gain = 1;
> > -		else
> > -			st->gain = 128;
> > -	}
> > -
> >  	return 0;
> >  }
> >  
> > @@ -173,8 +218,47 @@ static const struct ad7780_chip_info ad7780_chip_info_tbl[] = {
> >  
> >  static const struct iio_info ad7780_info = {
> >  	.read_raw = ad7780_read_raw,
> > +	.write_raw = ad7780_write_raw,
> >  };
> >  
> > +static int ad7780_init_gpios(struct device *dev, struct ad7780_state *st)
> > +{
> > +	int ret;
> > +
> > +	st->powerdown_gpio = devm_gpiod_get_optional(dev,
> > +						     "powerdown",
> > +						     GPIOD_OUT_LOW);
> > +	if (IS_ERR(st->powerdown_gpio)) {
> > +		ret = PTR_ERR(st->powerdown_gpio);
> > +		dev_err(dev, "Failed to request powerdown GPIO: %d\n", ret);
> > +		return ret;
> > +	}
> > +
> > +	if (!st->chip_info->is_ad778x)
> > +		return 0;
> > +  
> nitpick: One blank line is always enough. More just reduces the amount of
> code that can be seen at a time.
> 
> > +
> > +	st->gain_gpio = devm_gpiod_get_optional(dev,
> > +						"adi,gain",
> > +						GPIOD_OUT_HIGH);
> > +	if (IS_ERR(st->gain_gpio)) {
> > +		ret = PTR_ERR(st->gain_gpio);
> > +		dev_err(dev, "Failed to request gain GPIO: %d\n", ret);
> > +		return ret;
> > +	}
> > +
> > +	st->filter_gpio = devm_gpiod_get_optional(dev,
> > +						  "adi,filter",
> > +						  GPIOD_OUT_HIGH);
> > +	if (IS_ERR(st->filter_gpio)) {
> > +		ret = PTR_ERR(st->filter_gpio);
> > +		dev_err(dev, "Failed to request filter GPIO: %d\n", ret);
> > +		return ret;
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> >  static int ad7780_probe(struct spi_device *spi)
> >  {
> >  	struct ad7780_state *st;
> > @@ -212,15 +296,9 @@ static int ad7780_probe(struct spi_device *spi)
> >  	indio_dev->num_channels = 1;
> >  	indio_dev->info = &ad7780_info;
> >  
> > -	st->powerdown_gpio = devm_gpiod_get_optional(&spi->dev,
> > -						     "powerdown",
> > -						     GPIOD_OUT_LOW);
> > -	if (IS_ERR(st->powerdown_gpio)) {
> > -		ret = PTR_ERR(st->powerdown_gpio);
> > -		dev_err(&spi->dev, "Failed to request powerdown GPIO: %d\n",
> > -			ret);
> > -		goto error_disable_reg;
> > -	}
> > +	ret = ad7780_init_gpios(&spi->dev, st);
> > +	if (ret)
> > +		goto error_cleanup_buffer_and_trigger;
> >  
> >  	ret = ad_sd_setup_buffer_and_trigger(indio_dev);
> >  	if (ret)  
>
diff mbox series

Patch

diff --git a/drivers/staging/iio/adc/ad7780.c b/drivers/staging/iio/adc/ad7780.c
index c4a85789c2db..07e5e35c92a3 100644
--- a/drivers/staging/iio/adc/ad7780.c
+++ b/drivers/staging/iio/adc/ad7780.c
@@ -39,6 +39,9 @@ 
 #define AD7170_PATTERN		(AD7780_PAT0 | AD7170_PAT2)
 #define AD7170_PATTERN_MASK	(AD7780_PAT0 | AD7780_PAT1 | AD7170_PAT2)
 
+#define AD7780_GAIN_MIDPOINT	64
+#define AD7780_FILTER_MIDPOINT	13350
+
 struct ad7780_chip_info {
 	struct iio_chan_spec	channel;
 	unsigned int		pattern_mask;
@@ -50,7 +53,10 @@  struct ad7780_state {
 	const struct ad7780_chip_info	*chip_info;
 	struct regulator		*reg;
 	struct gpio_desc		*powerdown_gpio;
-	unsigned int	gain;
+	struct gpio_desc		*gain_gpio;
+	struct gpio_desc		*filter_gpio;
+	unsigned int			gain;
+	unsigned int			int_vref_mv;
 
 	struct ad_sigma_delta sd;
 };
@@ -104,8 +110,10 @@  static int ad7780_read_raw(struct iio_dev *indio_dev,
 		voltage_uv = regulator_get_voltage(st->reg);
 		if (voltage_uv < 0)
 			return voltage_uv;
-		*val = (voltage_uv / 1000) * st->gain;
+		voltage_uv /= 1000;
+		*val = voltage_uv * st->gain;
 		*val2 = chan->scan_type.realbits - 1;
+		st->int_vref_mv = voltage_uv;
 		return IIO_VAL_FRACTIONAL_LOG2;
 	case IIO_CHAN_INFO_OFFSET:
 		*val = -(1 << (chan->scan_type.realbits - 1));
@@ -115,6 +123,50 @@  static int ad7780_read_raw(struct iio_dev *indio_dev,
 	return -EINVAL;
 }
 
+static int ad7780_write_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan,
+			    int val,
+			    int val2,
+			    long m)
+{
+	struct ad7780_state *st = iio_priv(indio_dev);
+	const struct ad7780_chip_info *chip_info = st->chip_info;
+	unsigned long long vref;
+	unsigned int full_scale, gain;
+
+	if (!chip_info->is_ad778x)
+		return -EINVAL;
+
+	switch (m) {
+	case IIO_CHAN_INFO_SCALE:
+		if (val != 0)
+			return -EINVAL;
+
+		vref = st->int_vref_mv * 1000000LL;
+		full_scale = 1 << (chip_info->channel.scan_type.realbits - 1);
+		gain = DIV_ROUND_CLOSEST(vref, full_scale);
+		gain = DIV_ROUND_CLOSEST(gain, val2);
+		st->gain = gain;
+		if (gain < AD7780_GAIN_MIDPOINT)
+			gain = 0;
+		else
+			gain = 1;
+		gpiod_set_value(st->gain_gpio, gain);
+		break;
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		if (1000*val + val2/1000 < AD7780_FILTER_MIDPOINT)
+			val = 0;
+		else
+			val = 1;
+		gpiod_set_value(st->filter_gpio, val);
+		break;
+	default:
+		break;
+	}
+
+	return 0;
+}
+
 static int ad7780_postprocess_sample(struct ad_sigma_delta *sigma_delta,
 				     unsigned int raw_sample)
 {
@@ -125,13 +177,6 @@  static int ad7780_postprocess_sample(struct ad_sigma_delta *sigma_delta,
 	    ((raw_sample & chip_info->pattern_mask) != chip_info->pattern))
 		return -EIO;
 
-	if (chip_info->is_ad778x) {
-		if (raw_sample & AD7780_GAIN)
-			st->gain = 1;
-		else
-			st->gain = 128;
-	}
-
 	return 0;
 }
 
@@ -173,8 +218,47 @@  static const struct ad7780_chip_info ad7780_chip_info_tbl[] = {
 
 static const struct iio_info ad7780_info = {
 	.read_raw = ad7780_read_raw,
+	.write_raw = ad7780_write_raw,
 };
 
+static int ad7780_init_gpios(struct device *dev, struct ad7780_state *st)
+{
+	int ret;
+
+	st->powerdown_gpio = devm_gpiod_get_optional(dev,
+						     "powerdown",
+						     GPIOD_OUT_LOW);
+	if (IS_ERR(st->powerdown_gpio)) {
+		ret = PTR_ERR(st->powerdown_gpio);
+		dev_err(dev, "Failed to request powerdown GPIO: %d\n", ret);
+		return ret;
+	}
+
+	if (!st->chip_info->is_ad778x)
+		return 0;
+
+
+	st->gain_gpio = devm_gpiod_get_optional(dev,
+						"adi,gain",
+						GPIOD_OUT_HIGH);
+	if (IS_ERR(st->gain_gpio)) {
+		ret = PTR_ERR(st->gain_gpio);
+		dev_err(dev, "Failed to request gain GPIO: %d\n", ret);
+		return ret;
+	}
+
+	st->filter_gpio = devm_gpiod_get_optional(dev,
+						  "adi,filter",
+						  GPIOD_OUT_HIGH);
+	if (IS_ERR(st->filter_gpio)) {
+		ret = PTR_ERR(st->filter_gpio);
+		dev_err(dev, "Failed to request filter GPIO: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
 static int ad7780_probe(struct spi_device *spi)
 {
 	struct ad7780_state *st;
@@ -212,15 +296,9 @@  static int ad7780_probe(struct spi_device *spi)
 	indio_dev->num_channels = 1;
 	indio_dev->info = &ad7780_info;
 
-	st->powerdown_gpio = devm_gpiod_get_optional(&spi->dev,
-						     "powerdown",
-						     GPIOD_OUT_LOW);
-	if (IS_ERR(st->powerdown_gpio)) {
-		ret = PTR_ERR(st->powerdown_gpio);
-		dev_err(&spi->dev, "Failed to request powerdown GPIO: %d\n",
-			ret);
-		goto error_disable_reg;
-	}
+	ret = ad7780_init_gpios(&spi->dev, st);
+	if (ret)
+		goto error_cleanup_buffer_and_trigger;
 
 	ret = ad_sd_setup_buffer_and_trigger(indio_dev);
 	if (ret)