iio: dac: Add support for external reference voltage through the regulator framework.

PATCH In review Silvan Murer 3 participants 5 messages May 20, 2018 – May 23, 2018

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Device tree bindings IIO

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Silvan Murer

author

2018-05-20 00:19 UTC #0 lore raw

PATCH v3 1/1 iio: dac: Add support for external reference voltage through the regulator framework.

Add support for external reference voltage through the regulator framework.

Signed-off-by Silvan Murer <[email protected]>

Reviewed-by Lars-Peter Clausen <[email protected]>

---
Changes in v3:
- remove extra spaces and tab
Changes in v2:
- Add 'optional properties' documentation
- Return an error when a regulator is specified
- Use internal reference when no regulator is specified
- Use iio_device_register instead of devm_iio_device_register

.../devicetree/bindings/iio/dac/ltc2632.txt | 14 +++++ drivers/iio/dac/ltc2632.c | 70 +++++++++++++++++++---

 2 files changed, 75 insertions(+), 9 deletions(-)

Documentation/devicetree/bindings/iio/dac/ltc2632.txt +0 -0

index eb911e5..e0d5fea 100644
@@ -12,12 +12,26 @@ Required properties:

Property rules described in Documentation/devicetree/bindings/spi/spi-bus.txt apply. In particular, "reg" and "spi-max-frequency" properties must be given.
+Optional properties:
+ - vref-supply: Phandle to the external reference voltage supply. This should
+ only be set if there is an external reference voltage connected to the VREF
+ pin. If the property is not set the internal reference is used.
+
Example:

+ vref: regulator-vref {
+ compatible = "regulator-fixed";
+ regulator-name = "vref-ltc2632";
+ regulator-min-microvolt = <1250000>;
+ regulator-max-microvolt = <1250000>;
+ regulator-always-on;
+ };
+
spi_master {
dac: ltc2632@0 {
compatible = "lltc,ltc2632-l12";
reg = <0>; /* CS0 */
spi-max-frequency = <1000000>;
+ vref-supply = <&vref>; /* optional */
};
};

drivers/iio/dac/ltc2632.c +0 -0

index d322b78..9551156 100644
@@ -2,6 +2,7 @@

* LTC2632 Digital to analog convertors spi driver
*
* Copyright 2017 Maxime Roussin-Bélanger
+ * expanded by Silvan Murer <[email protected]>
*
* Licensed under the GPL-2.
*/
@@ -10,6 +11,7 @@
#include <linux/spi/spi.h>
#include <linux/module.h>
#include <linux/iio/iio.h>
+#include <linux/regulator/consumer.h>

#define LTC2632_DAC_CHANNELS 2

@@ -28,7 +30,7 @@
/**
* struct ltc2632_chip_info - chip specific information
* @channels: channel spec for the DAC
- * @vref_mv: reference voltage
+ * @vref_mv: internal reference voltage
*/
struct ltc2632_chip_info {
const struct iio_chan_spec *channels;
@@ -39,10 +41,14 @@ struct ltc2632_chip_info {
* struct ltc2632_state - driver instance specific data
* @spi_dev: pointer to the spi_device struct
* @powerdown_cache_mask used to show current channel powerdown state
+ * @vref_mv used reference voltage (internal or external)
+ * @vref_reg regulator for the reference voltage
*/
struct ltc2632_state {
struct spi_device *spi_dev;
unsigned int powerdown_cache_mask;
+ int vref_mv;
+ struct regulator *vref_reg;
};

enum ltc2632_supported_device_ids {
@@ -90,7 +96,7 @@ static int ltc2632_read_raw(struct iio_dev *indio_dev,
switch (m) {
case IIO_CHAN_INFO_SCALE:
- *val = chip_info->vref_mv;
+ *val = st->vref_mv;
*val2 = chan->scan_type.realbits;
return IIO_VAL_FRACTIONAL_LOG2;
}
@@ -247,6 +253,45 @@ static int ltc2632_probe(struct spi_device *spi) chip_info = (struct ltc2632_chip_info *) spi_get_device_id(spi)->driver_data;

+ st->vref_reg = devm_regulator_get_optional(&spi->dev, "vref");
+ if (PTR_ERR(st->vref_reg) == -ENODEV) {
+ /* use internal reference voltage */
+ st->vref_reg = NULL;
+ st->vref_mv = chip_info->vref_mv;
+
+ ret = ltc2632_spi_write(spi, LTC2632_CMD_INTERNAL_REFER,
+ 0, 0, 0);
+ if (ret) {
+ dev_err(&spi->dev,
+ "Set internal reference command failed, %d\n",
+ ret);
+ return ret;
+ }
+ } else if (IS_ERR(st->vref_reg)) {
+ dev_err(&spi->dev,
+ "Error getting voltage reference regulator\n");
+ return PTR_ERR(st->vref_reg);
+ } else {
+ /* use external reference voltage */
+ ret = regulator_enable(st->vref_reg);
+ if (ret) {
+ dev_err(&spi->dev,
+ "enable reference regulator failed, %d\n",
+ ret);
+ return ret;
+ }
+ st->vref_mv = regulator_get_voltage(st->vref_reg) / 1000;
+
+ ret = ltc2632_spi_write(spi, LTC2632_CMD_EXTERNAL_REFER,
+ 0, 0, 0);
+ if (ret) {
+ dev_err(&spi->dev,
+ "Set external reference command failed, %d\n",
+ ret);
+ return ret;
+ }
+ }
+
indio_dev->dev.parent = &spi->dev;
indio_dev->name = dev_of_node(&spi->dev) ? dev_of_node(&spi->dev)->name : spi_get_device_id(spi)->name; @@ -255,14 +300,20 @@ static int ltc2632_probe(struct spi_device *spi) indio_dev->channels = chip_info->channels; indio_dev->num_channels = LTC2632_DAC_CHANNELS;

- ret = ltc2632_spi_write(spi, LTC2632_CMD_INTERNAL_REFER, 0, 0, 0);
- if (ret) {
- dev_err(&spi->dev,
- "Set internal reference command failed, %d\n", ret);
- return ret;
- }
+ return iio_device_register(indio_dev);
+}
+
+static int ltc2632_remove(struct spi_device *spi)
+{
+ struct iio_dev *indio_dev = spi_get_drvdata(spi);
+ struct ltc2632_state *st = iio_priv(indio_dev);
+
+ iio_device_unregister(indio_dev);
+
+ if (st->vref_reg)
+ regulator_disable(st->vref_reg);

- return devm_iio_device_register(&spi->dev, indio_dev);
+ return 0;
}

static const struct spi_device_id ltc2632_id[] = {
@@ -306,6 +357,7 @@ static struct spi_driver ltc2632_driver = { .of_match_table = of_match_ptr(ltc2632_of_match), },
.probe = ltc2632_probe,
+ .remove = ltc2632_remove,
.id_table = ltc2632_id,
};
module_spi_driver(ltc2632_driver);
--
2.7.4

Jonathan Cameron

maintainer

2018-05-20 10:23 UTC #1 lore raw

Quoted 4 lines · On Sun, 20 May 2018 02:19:17 +0200 Silvan Murer <[email protected]> wrote:

Add support for external reference voltage through the regulator framework.
Signed-off-by Silvan Murer <[email protected]>
Reviewed-by Lars-Peter Clausen <[email protected]>

Content looks fine, but I'm having the same issue with subtle issues with patch formatting. Please check and see if you can figure out what is causing this.

Anyhow, I'd like this to sit on the lists a little longer to give time for Devicetree binding feedback.

Thanks,

Jonathan

Quoted 181 lines

.../devicetree/bindings/iio/dac/ltc2632.txt | 14 +++++ drivers/iio/dac/ltc2632.c | 70 +++++++++++++++++++---

 2 files changed, 75 insertions(+), 9 deletions(-)

Documentation/devicetree/bindings/iio/dac/ltc2632.txt +0 -0

index eb911e5..e0d5fea 100644
@@ -12,12 +12,26 @@ Required properties:

Property rules described in Documentation/devicetree/bindings/spi/spi-bus.txt apply. In particular, "reg" and "spi-max-frequency" properties must be given.

Documentation/devicetree/bindings/iio/dac/ltc2632.txt +5 -0

+Optional properties:
+	- vref-supply: Phandle to the external reference voltage supply. This should
+	  only be set if there is an external reference voltage connected to the VREF
+	  pin. If the property is not set the internal reference is used.
+

Example:

Documentation/devicetree/bindings/iio/dac/ltc2632.txt +8 -0

+	vref: regulator-vref {
+		compatible = "regulator-fixed";
+		regulator-name = "vref-ltc2632";
+		regulator-min-microvolt = <1250000>;
+		regulator-max-microvolt = <1250000>;
+		regulator-always-on;
+	};
+

spi_master {
dac: ltc2632@0 {
compatible = "lltc,ltc2632-l12"; reg = <0>; /* CS0 */ spi-max-frequency = <1000000>;

Documentation/devicetree/bindings/iio/dac/ltc2632.txt +1 -0

+			vref-supply = <&vref>; /* optional */

};
};

drivers/iio/dac/ltc2632.c +2 -0

index d322b78..9551156 100644
@@ -2,6 +2,7 @@
   * LTC2632 Digital to analog convertors spi driver
   *
   * Copyright 2017 Maxime Roussin-Bélanger
+ * expanded by Silvan Murer <[email protected]>
   *
   * Licensed under the GPL-2.
   */

@@ -10,6 +11,7 @@
  #include <linux/spi/spi.h>
  #include <linux/module.h>
  #include <linux/iio/iio.h>
+#include <linux/regulator/consumer.h>

#define LTC2632_DAC_CHANNELS 2

drivers/iio/dac/ltc2632.c +5 -1

@@ -28,7 +30,7 @@
  /**
   * struct ltc2632_chip_info - chip specific information
   * @channels:		channel spec for the DAC
- * @vref_mv:		reference voltage
+ * @vref_mv:		internal reference voltage
   */
  struct ltc2632_chip_info {
  	const struct iio_chan_spec *channels;

@@ -39,10 +41,14 @@ struct ltc2632_chip_info {
   * struct ltc2632_state - driver instance specific data
   * @spi_dev:			pointer to the spi_device struct
   * @powerdown_cache_mask	used to show current channel powerdown state
+ * @vref_mv			used reference voltage (internal or external)
+ * @vref_reg		regulator for the reference voltage
   */
  struct ltc2632_state {
  	struct spi_device *spi_dev;
  	unsigned int powerdown_cache_mask;
+	int vref_mv;
+	struct regulator *vref_reg;
  };

enum ltc2632_supported_device_ids {

drivers/iio/dac/ltc2632.c +0 -0

@@ -90,7 +96,7 @@ static int ltc2632_read_raw(struct iio_dev *indio_dev,

switch (m) {
case IIO_CHAN_INFO_SCALE:

drivers/iio/dac/ltc2632.c +1 -1

-		*val = chip_info->vref_mv;
+		*val = st->vref_mv;

*val2 = chan->scan_type.realbits;
return IIO_VAL_FRACTIONAL_LOG2;
}

drivers/iio/dac/ltc2632.c +0 -0

@@ -247,6 +253,45 @@ static int ltc2632_probe(struct spi_device *spi)
  	chip_info = (struct ltc2632_chip_info *)
  			spi_get_device_id(spi)->driver_data;

drivers/iio/dac/ltc2632.c +39 -0

+	st->vref_reg = devm_regulator_get_optional(&spi->dev, "vref");
+	if (PTR_ERR(st->vref_reg) == -ENODEV) {
+		/* use internal reference voltage */
+		st->vref_reg = NULL;
+		st->vref_mv = chip_info->vref_mv;
+
+		ret = ltc2632_spi_write(spi, LTC2632_CMD_INTERNAL_REFER,
+				0, 0, 0);
+		if (ret) {
+			dev_err(&spi->dev,
+				"Set internal reference command failed, %d\n",
+				ret);
+			return ret;
+		}
+	} else if (IS_ERR(st->vref_reg)) {
+		dev_err(&spi->dev,
+				"Error getting voltage reference regulator\n");
+		return PTR_ERR(st->vref_reg);
+	} else {
+		/* use external reference voltage */
+		ret = regulator_enable(st->vref_reg);
+		if (ret) {
+			dev_err(&spi->dev,
+				"enable reference regulator failed, %d\n",
+				ret);
+			return ret;
+		}
+		st->vref_mv = regulator_get_voltage(st->vref_reg) / 1000;
+
+		ret = ltc2632_spi_write(spi, LTC2632_CMD_EXTERNAL_REFER,
+				0, 0, 0);
+		if (ret) {
+			dev_err(&spi->dev,
+				"Set external reference command failed, %d\n",
+				ret);
+			return ret;
+		}
+	}
+

indio_dev->dev.parent = &spi->dev;
indio_dev->name = dev_of_node(&spi->dev) ? dev_of_node(&spi->dev)->name : spi_get_device_id(spi)->name;

drivers/iio/dac/ltc2632.c +0 -0

@@ -255,14 +300,20 @@ static int ltc2632_probe(struct spi_device *spi)
  	indio_dev->channels = chip_info->channels;
  	indio_dev->num_channels = LTC2632_DAC_CHANNELS;

drivers/iio/dac/ltc2632.c +12 -6

-	ret = ltc2632_spi_write(spi, LTC2632_CMD_INTERNAL_REFER, 0, 0, 0);
-	if (ret) {
-		dev_err(&spi->dev,
-			"Set internal reference command failed, %d\n", ret);
-		return ret;
-	}
+	return iio_device_register(indio_dev);
+}
+
+static int ltc2632_remove(struct spi_device *spi)
+{
+	struct iio_dev *indio_dev = spi_get_drvdata(spi);
+	struct ltc2632_state *st = iio_priv(indio_dev);
+
+	iio_device_unregister(indio_dev);
+
+	if (st->vref_reg)
+		regulator_disable(st->vref_reg);

drivers/iio/dac/ltc2632.c +1 -1

-	return devm_iio_device_register(&spi->dev, indio_dev);
+	return 0;

}

static const struct spi_device_id ltc2632_id[] = {

drivers/iio/dac/ltc2632.c +1 -0

@@ -306,6 +357,7 @@ static struct spi_driver ltc2632_driver = {
  		.of_match_table = of_match_ptr(ltc2632_of_match),
  	},
  	.probe		= ltc2632_probe,
+	.remove		= ltc2632_remove,
  	.id_table	= ltc2632_id,
  };
  module_spi_driver(ltc2632_driver);

--
2.7.4

Silvan Murer

author

2018-05-21 12:29 UTC #2 lore raw

Hi Jonathan,
Many Thanks for your kindly feedback and your patience!
I changed my patch process and sent them now (v4) with the "git sent- email" command. I think this would be much more stable now. I could also test the patch by store the mail as mbox and patch them with the "git am" command into the clean repository.
Let me know, if it works to on your side to verify my new patch process.
Thanks for your work and patience
Silvan

Quoted 228 lines · Jonathan Cameron

Quoted 6 lines · On Sun, 20 May 2018 02:19:17 +0200 Silvan Murer <[email protected]> wrote:
Add support for external reference voltage through the regulator framework.
Signed-off-by Silvan Murer <[email protected]>
Reviewed-by Lars-Peter Clausen <[email protected]>
Content looks fine, but I'm having the same issue with subtle issues with
patch formatting. Please check and see if you can figure out what is causing this.
Anyhow, I'd like this to sit on the lists a little longer to give time for Devicetree binding feedback.
Thanks,
Jonathan
Quoted 207 lines
---
Changes in v3:
- remove extra spaces and tab
Changes in v2:
- Add 'optional properties' documentation
- Return an error when a regulator is specified
- Use internal reference when no regulator is specified
- Use iio_device_register instead of devm_iio_device_register
.../devicetree/bindings/iio/dac/ltc2632.txt | 14 +++++ drivers/iio/dac/ltc2632.c | 70
+++++++++++++++++++---
 2 files changed, 75 insertions(+), 9 deletions(-)
Documentation/devicetree/bindings/iio/dac/ltc2632.txt +0 -0
index eb911e5..e0d5fea 100644
@@ -12,12 +12,26 @@ Required properties:
Property rules described in Documentation/devicetree/bindings/spi/spi-bus.txt apply. In particular, "reg" and "spi-max-frequency" properties must be given.
Documentation/devicetree/bindings/iio/dac/ltc2632.txt +2 -0
+Optional properties:
+	- vref-supply: Phandle to the external reference voltage
supply. This should
Documentation/devicetree/bindings/iio/dac/ltc2632.txt +1 -0
+	  only be set if there is an external reference voltage
connected to the VREF
Documentation/devicetree/bindings/iio/dac/ltc2632.txt +1 -0
+	  pin. If the property is not set the internal reference
is used.
+
Example:
Documentation/devicetree/bindings/iio/dac/ltc2632.txt +8 -0
+	vref: regulator-vref {
+		compatible = "regulator-fixed";
+		regulator-name = "vref-ltc2632";
+		regulator-min-microvolt = <1250000>;
+		regulator-max-microvolt = <1250000>;
+		regulator-always-on;
+	};
+
spi_master {
dac: ltc2632@0 {
compatible = "lltc,ltc2632-l12"; reg = <0>; /* CS0 */ spi-max-frequency = <1000000>;
Documentation/devicetree/bindings/iio/dac/ltc2632.txt +1 -0
+			vref-supply = <&vref>; /* optional */
};
};
drivers/iio/dac/ltc2632.c +2 -0
index d322b78..9551156 100644
@@ -2,6 +2,7 @@
   * LTC2632 Digital to analog convertors spi driver
   *
   * Copyright 2017 Maxime Roussin-Bélanger
+ * expanded by Silvan Murer <[email protected]>
   *
   * Licensed under the GPL-2.
   */
@@ -10,6 +11,7 @@
  #include <linux/spi/spi.h>
  #include <linux/module.h>
  #include <linux/iio/iio.h>
+#include <linux/regulator/consumer.h>
#define LTC2632_DAC_CHANNELS 2
drivers/iio/dac/ltc2632.c +1 -1
@@ -28,7 +30,7 @@
  /**
   * struct ltc2632_chip_info - chip specific information
   * @channels:		channel spec for the DAC
- * @vref_mv:		reference voltage
+ * @vref_mv:		internal reference voltage
   */
  struct ltc2632_chip_info {
  	const struct iio_chan_spec *channels;
@@ -39,10 +41,14 @@ struct ltc2632_chip_info {
   * struct ltc2632_state - driver instance specific data
   * @spi_dev:			pointer to the spi_device
struct
* @powerdown_cache_mask used to show current channel
powerdown state
+ * @vref_mv used reference voltage
(internal or external)
+ * @vref_reg regulator for the reference voltage
*/
struct ltc2632_state {
struct spi_device *spi_dev;
unsigned int powerdown_cache_mask;
drivers/iio/dac/ltc2632.c +2 -0
+	int vref_mv;
+	struct regulator *vref_reg;
};

enum ltc2632_supported_device_ids {
drivers/iio/dac/ltc2632.c +0 -0
@@ -90,7 +96,7 @@ static int ltc2632_read_raw(struct iio_dev
 *indio_dev,
switch (m) {
case IIO_CHAN_INFO_SCALE:
drivers/iio/dac/ltc2632.c +1 -1
-		*val = chip_info->vref_mv;
+		*val = st->vref_mv;
*val2 = chan->scan_type.realbits;
return IIO_VAL_FRACTIONAL_LOG2;
}
drivers/iio/dac/ltc2632.c +0 -0
@@ -247,6 +253,45 @@ static int ltc2632_probe(struct spi_device
 *spi)
  	chip_info = (struct ltc2632_chip_info *)
  			spi_get_device_id(spi)->driver_data;
drivers/iio/dac/ltc2632.c +1 -0
+	st->vref_reg = devm_regulator_get_optional(&spi->dev,
"vref");
drivers/iio/dac/ltc2632.c +6 -0
+	if (PTR_ERR(st->vref_reg) == -ENODEV) {
+		/* use internal reference voltage */
+		st->vref_reg = NULL;
+		st->vref_mv = chip_info->vref_mv;
+
+		ret = ltc2632_spi_write(spi,
LTC2632_CMD_INTERNAL_REFER,
drivers/iio/dac/ltc2632.c +4 -0
+				0, 0, 0);
+		if (ret) {
+			dev_err(&spi->dev,
+				"Set internal reference command
failed, %d\n",
drivers/iio/dac/ltc2632.c +6 -0
+				ret);
+			return ret;
+		}
+	} else if (IS_ERR(st->vref_reg)) {
+		dev_err(&spi->dev,
+				"Error getting voltage reference
regulator\n");
drivers/iio/dac/ltc2632.c +7 -0
+		return PTR_ERR(st->vref_reg);
+	} else {
+		/* use external reference voltage */
+		ret = regulator_enable(st->vref_reg);
+		if (ret) {
+			dev_err(&spi->dev,
+				"enable reference regulator
failed, %d\n",
drivers/iio/dac/ltc2632.c +4 -0
+				ret);
+			return ret;
+		}
+		st->vref_mv = regulator_get_voltage(st->vref_reg)
/ 1000;
drivers/iio/dac/ltc2632.c +2 -0
+
+		ret = ltc2632_spi_write(spi,
LTC2632_CMD_EXTERNAL_REFER,
drivers/iio/dac/ltc2632.c +4 -0
+				0, 0, 0);
+		if (ret) {
+			dev_err(&spi->dev,
+				"Set external reference command
failed, %d\n",
drivers/iio/dac/ltc2632.c +5 -0
+				ret);
+			return ret;
+		}
+	}
+
indio_dev->dev.parent = &spi->dev; indio_dev->name = dev_of_node(&spi->dev) ? dev_of_node(&spi->dev)->name
:
spi_get_device_id(spi)->name;
drivers/iio/dac/ltc2632.c +0 -0
@@ -255,14 +300,20 @@ static int ltc2632_probe(struct spi_device
 *spi)
  	indio_dev->channels = chip_info->channels;
  	indio_dev->num_channels = LTC2632_DAC_CHANNELS;
drivers/iio/dac/ltc2632.c +0 -1
-	ret = ltc2632_spi_write(spi, LTC2632_CMD_INTERNAL_REFER,
0, 0, 0);
drivers/iio/dac/ltc2632.c +0 -3
-	if (ret) {
-		dev_err(&spi->dev,
-			"Set internal reference command failed,
%d\n", ret);
drivers/iio/dac/ltc2632.c +12 -2
-		return ret;
-	}
+	return iio_device_register(indio_dev);
+}
+
+static int ltc2632_remove(struct spi_device *spi)
+{
+	struct iio_dev *indio_dev = spi_get_drvdata(spi);
+	struct ltc2632_state *st = iio_priv(indio_dev);
+
+	iio_device_unregister(indio_dev);
+
+	if (st->vref_reg)
+		regulator_disable(st->vref_reg);
drivers/iio/dac/ltc2632.c +1 -1
-	return devm_iio_device_register(&spi->dev, indio_dev);
+	return 0;
}

static const struct spi_device_id ltc2632_id[] = {
drivers/iio/dac/ltc2632.c +1 -0
@@ -306,6 +357,7 @@ static struct spi_driver ltc2632_driver = {
  		.of_match_table = of_match_ptr(ltc2632_of_match),
  	},
  	.probe		= ltc2632_probe,
+	.remove		= ltc2632_remove,
  	.id_table	= ltc2632_id,
  };
  module_spi_driver(ltc2632_driver);
--
2.7.4

Rob Herring

maintainer Reviewed-by on v3 1/1

2018-05-22 17:19 UTC #3 lore raw

In reply to Silvan Murer

Quoted 13 lines · Silvan Murer

Add support for external reference voltage through the regulator framework.
Signed-off-by Silvan Murer <[email protected]>
Reviewed-by Lars-Peter Clausen <[email protected]>
---
Changes in v3:
- remove extra spaces and tab
Changes in v2:
- Add 'optional properties' documentation
- Return an error when a regulator is specified
- Use internal reference when no regulator is specified
- Use iio_device_register instead of devm_iio_device_register

Quoted 1 line

ï¿½.../devicetree/bindings/iio/dac/ltc2632.txtï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½| 14 +++++

Reviewed-by Rob Herring <[email protected]>

In the future, please split bindings to separate patch.

Quoted 2 lines

ï¿½drivers/iio/dac/ltc2632.cï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½| 70 +++++++++++++++++++--- ï¿½2 files changed, 75 insertions(+), 9 deletions(-)

Silvan Murer

author

2018-05-23 07:17 UTC #4 lore raw

Thanks Rob for the review and the feedback!
In the next patches, I split the bindings to a separate patch.

Quoted 25 lines · Rob Herring

Quoted 15 lines · Silvan Murer
Add support for external reference voltage through the regulator framework.
Signed-off-by Silvan Murer <[email protected]>
Reviewed-by Lars-Peter Clausen <[email protected]>
---
Changes in v3:
- remove extra spaces and tab
Changes in v2:
- Add 'optional properties' documentation
- Return an error when a regulator is specified
- Use internal reference when no regulator is specified
- Use iio_device_register instead of devm_iio_device_register
Quoted 1 line
.../devicetree/bindings/iio/dac/ltc2632.txt | 14 +++++
Reviewed-by Rob Herring <[email protected]>
In the future, please split bindings to separate patch.
Quoted 4 lines
drivers/iio/dac/ltc2632.c | 70
+++++++++++++++++++---
 2 files changed, 75 insertions(+), 9 deletions(-)