[PATCH 1/2] iio: dac: ad5337: Add driver for the AD5337 DAC

[PATCH 1/2] iio: dac: ad5337: Add driver for the AD5337 DAC

[Marcin Bis]

Add driver for the AD5337 dual 8-bit I2C voltage-output DAC.
This part uses the pointer-byte protocol and is not compatible with
the AD5337R nanoDAC+ driver (adi,ad5337r).

Signed-off-by: Marcin Bis <marcin@bis-linux.com>
---
 MAINTAINERS              |   5 ++
 drivers/iio/dac/Kconfig  |  12 ++-
 drivers/iio/dac/Makefile |   1 +
 drivers/iio/dac/ad5337.c | 159 +++++++++++++++++++++++++++++++++++++++
 4 files changed, 176 insertions(+), 1 deletion(-)
 create mode 100644 drivers/iio/dac/ad5337.c

diff --git a/MAINTAINERS b/MAINTAINERS
index e035a3be797c..614589b6efa4 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -438,6 +438,11 @@ W:	http://wiki.analog.com/AD5398
 W:	https://ez.analog.com/linux-software-drivers
 F:	drivers/regulator/ad5398.c
 
+AD5337  ANALOG DEVICES INC AD5337 DAC DRIVER
+M:	Marcin Bis <marcin@bis-linux.com>
+S:	Maintained
+F:	drivers/iio/dac/ad5337.c
+
 AD5446	ANALOG DEVICES INC AD5446 DAC DRIVER
 M:	Michael Hennerich <michael.hennerich@analog.com>
 M:	Nuno Sá <nuno.sa@analog.com>
diff --git a/drivers/iio/dac/Kconfig b/drivers/iio/dac/Kconfig
index cd4870b65415..de2bc2ec2269 100644
--- a/drivers/iio/dac/Kconfig
+++ b/drivers/iio/dac/Kconfig
@@ -62,6 +62,16 @@ config AD5064
 	  To compile this driver as a module, choose M here: the
 	  module will be called ad5064.
 
+config AD5337
+	tristate "Analog Devices AD5337 I2C DAC"
+	depends on I2C
+	help
+	  Say yes here to build support for the Analog Devices AD5337 dual
+	  8-bit I2C voltage-output DAC.
+
+	  To compile this driver as a module, choose M here: the module will be
+	  called ad5337.
+
 config AD5360
 	tristate "Analog Devices AD5360/61/62/63/70/71/73 DAC driver"
 	depends on SPI
@@ -247,7 +257,7 @@ config AD5696_I2C
 	depends on I2C
 	select AD5686
 	help
-	  Say yes here to build support for Analog Devices AD5311R, AD5337,
+	  Say yes here to build support for Analog Devices AD5311R, AD5337R,
 	  AD5338R, AD5671R, AD5673R, AD5675R, AD5677R, AD5691R, AD5692R, AD5693,
 	  AD5693R, AD5694, AD5694R, AD5695R, AD5696, and AD5696R Digital to
 	  Analog converters.
diff --git a/drivers/iio/dac/Makefile b/drivers/iio/dac/Makefile
index 2a80bbf4e80a..1adf80dde4cc 100644
--- a/drivers/iio/dac/Makefile
+++ b/drivers/iio/dac/Makefile
@@ -8,6 +8,7 @@ obj-$(CONFIG_AD3530R) += ad3530r.o
 obj-$(CONFIG_AD3552R_HS) += ad3552r-hs.o
 obj-$(CONFIG_AD3552R_LIB) += ad3552r-common.o
 obj-$(CONFIG_AD3552R) += ad3552r.o
+obj-$(CONFIG_AD5337) += ad5337.o
 obj-$(CONFIG_AD5360) += ad5360.o
 obj-$(CONFIG_AD5380) += ad5380.o
 obj-$(CONFIG_AD5421) += ad5421.o
diff --git a/drivers/iio/dac/ad5337.c b/drivers/iio/dac/ad5337.c
new file mode 100644
index 000000000000..b983baa203fe
--- /dev/null
+++ b/drivers/iio/dac/ad5337.c
@@ -0,0 +1,159 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Analog Devices AD5337 I2C DAC driver
+ *
+ * Copyright 2017 Marcin Bis <marcin@bis-linux.com>
+ */
+
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/regulator/consumer.h>
+
+#include <linux/iio/iio.h>
+
+#define AD5337_NUM_CHANNELS	2
+#define AD5337_RESOLUTION	8
+/*
+ * AD5338 - 10bit, AD5339 - 12bit
+ */
+
+#define AD5337_PTR_DAC_A	0x01
+#define AD5337_PTR_DAC_B	0x02
+
+struct ad5337_state {
+	struct i2c_client *client;
+	struct mutex lock;
+	unsigned int vref_mv;
+	u8 cache[AD5337_NUM_CHANNELS];
+};
+
+static int ad5337_write_dac(struct ad5337_state *st, int channel, u8 value)
+{
+	u8 buf[3];
+	int ret;
+
+	if (channel)
+		buf[0] = AD5337_PTR_DAC_B;
+	else
+		buf[0] = AD5337_PTR_DAC_A;
+
+	/* PD1=0, PD0=0, CLR=1, LDAC=0, D[7:4] */
+	buf[1] = 0x20 | (value >> 4);
+	buf[2] = (value & 0x0f) << 4;
+
+	ret = i2c_master_send(st->client, buf, 3);
+
+	return (ret < 0) ? ret : (ret == 3 ? 0 : -EIO);
+}
+
+static int ad5337_read_raw(struct iio_dev *indio_dev,
+			   struct iio_chan_spec const *chan,
+			   int *val, int *val2, long mask)
+{
+	struct ad5337_state *st = iio_priv(indio_dev);
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		*val = st->cache[chan->channel];
+		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_SCALE:
+		*val = st->vref_mv;
+		*val2 = AD5337_RESOLUTION;
+		return IIO_VAL_FRACTIONAL_LOG2;
+	default:
+		return -EINVAL;
+	}
+}
+
+static int ad5337_write_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan,
+			    int val, int val2, long mask)
+{
+	struct ad5337_state *st = iio_priv(indio_dev);
+	int ret;
+
+	if (mask != IIO_CHAN_INFO_RAW)
+		return -EINVAL;
+
+	if (val < 0 || val > ((1 << AD5337_RESOLUTION) - 1))
+		return -EINVAL;
+
+	mutex_lock(&st->lock);
+	ret = ad5337_write_dac(st, chan->channel, val);
+	if (!ret)
+		st->cache[chan->channel] = val;
+	mutex_unlock(&st->lock);
+
+	return ret;
+}
+
+static const struct iio_info ad5337_info = {
+	.read_raw = ad5337_read_raw,
+	.write_raw = ad5337_write_raw,
+};
+
+#define AD5337_CHANNEL(_chan) {						\
+	.type = IIO_VOLTAGE,						\
+	.indexed = 1,							\
+	.output = 1,							\
+	.channel = (_chan),						\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),			\
+	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),		\
+}
+
+static const struct iio_chan_spec ad5337_channels[] = {
+	AD5337_CHANNEL(0),
+	AD5337_CHANNEL(1),
+};
+
+static int ad5337_probe(struct i2c_client *client)
+{
+	struct ad5337_state *st;
+	struct iio_dev *indio_dev;
+	int ret;
+
+	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
+		return -ENODEV;
+
+	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*st));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	st = iio_priv(indio_dev);
+	st->client = client;
+	mutex_init(&st->lock);
+
+	ret = devm_regulator_get_enable_read_voltage(&client->dev, "vcc");
+	if (ret < 0 && ret != -ENODEV)
+		return ret;
+
+	st->vref_mv = ret > 0 ? ret / 1000 : 3300;
+
+	indio_dev->name = "ad5337";
+	indio_dev->info = &ad5337_info;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->channels = ad5337_channels;
+	indio_dev->num_channels = ARRAY_SIZE(ad5337_channels);
+
+	return devm_iio_device_register(&client->dev, indio_dev);
+}
+
+static const struct of_device_id ad5337_of_match[] = {
+	{ .compatible = "adi,ad5337" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, ad5337_of_match);
+
+static struct i2c_driver ad5337_driver = {
+	.driver = {
+		.name = "ad5337",
+		.of_match_table = ad5337_of_match,
+	},
+	.probe = ad5337_probe,
+};
+module_i2c_driver(ad5337_driver);
+
+MODULE_AUTHOR("Marcin Bis <marcin@bis-linux.com>");
+MODULE_DESCRIPTION("Analog Devices AD5337 I2C DAC");
+MODULE_LICENSE("GPL");
-- 
2.43.0

[PATCH 2/2] dt-bindings: iio: dac: adi,ad5337: add dt-bindings

[Marcin Bis]

Add dt-bindings for the AD5337 dual 8-bit I2C voltage-output DAC driver.

Signed-off-by: Marcin Bis <marcin@bis-linux.com>
---
 .../bindings/iio/dac/adi,ad5337.yaml          | 48 +++++++++++++++++++
 MAINTAINERS                                   |  1 +
 2 files changed, 49 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/iio/dac/adi,ad5337.yaml

diff --git a/Documentation/devicetree/bindings/iio/dac/adi,ad5337.yaml b/Documentation/devicetree/bindings/iio/dac/adi,ad5337.yaml
new file mode 100644
index 000000000000..327a45ccfe4a
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/dac/adi,ad5337.yaml
@@ -0,0 +1,48 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iio/dac/adi,ad5337.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Analog Devices AD5337 I2C DAC
+
+maintainers:
+  - Marcin Bis <marcin@bis-linux.com>
+
+description:
+  Binding for the AD5337 dual 8-bit I2C voltage-output DAC.
+  This part uses the pointer-byte protocol and is not compatible with
+  the AD5337R nanoDAC+ driver (adi,ad5337r).
+
+properties:
+  compatible:
+    const: adi,ad5337
+
+  reg:
+    maxItems: 1
+    description:
+      7-bit I2C address. 0x0c when A0 is low, 0x0d when A0 is high.
+
+  vcc-supply:
+    description: DAC reference voltage supply.
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    i2c {
+      #address-cells = <1>;
+      #size-cells = <0>;
+
+      dac@0c {
+        compatible = "adi,ad5337";
+        reg = <0x0c>;
+        vcc-supply = <&dac_3v3>;
+      };
+    };
+
+...
diff --git a/MAINTAINERS b/MAINTAINERS
index 614589b6efa4..f967c18fe730 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -441,6 +441,7 @@ F:	drivers/regulator/ad5398.c
 AD5337  ANALOG DEVICES INC AD5337 DAC DRIVER
 M:	Marcin Bis <marcin@bis-linux.com>
 S:	Maintained
+F:	Documentation/devicetree/bindings/iio/dac/adi,ad5337.yaml
 F:	drivers/iio/dac/ad5337.c
 
 AD5446	ANALOG DEVICES INC AD5446 DAC DRIVER
-- 
2.43.0

Re: [PATCH 2/2] dt-bindings: iio: dac: adi,ad5337: add dt-bindings

[Joshua Crofts]

On Fri, 12 Jun 2026 15:31:22 +0200
Marcin Bis <marcin@bis-linux.com> wrote:

> Add dt-bindings for the AD5337 dual 8-bit I2C voltage-output DAC driver.
> 
> Signed-off-by: Marcin Bis <marcin@bis-linux.com>
> ---

If you're adding new device support, any dt-binding patches
should go first in the series.

Another big problem is that you haven't cc'd any devicetree
maintainers/reviewers, nor the devicetree mailing list, therefore
they probably won't see this patch and their automated tooling
definitely won't check this. If you're unsure where to send this
patch to, use the get_maintainer.pl script.

Also, it seems that you've replied with this patch to the
first patch in the series, making it appear strangely in my
(and probably other people's) email clients. Use a cover
letter when sending patch series, it prevents things like
this from happening.

+cc'd devicetree@vger.kernel.org

-- 
Kind regards

CJD

Re: [PATCH 2/2] dt-bindings: iio: dac: adi,ad5337: add dt-bindings

[Jonathan Cameron]

On Fri, 12 Jun 2026 15:31:22 +0200
Marcin Bis <marcin@bis-linux.com> wrote:

> Add dt-bindings for the AD5337 dual 8-bit I2C voltage-output DAC driver.
> 
What is the relationship between this part and the ad5337r which is supported
by the ad5696-i2c.c driver and adi,ad5696.yaml?

I'm wondering if there actually is an ad5337r or whether it was always meant to
be this device. I can't find a datasheet for it.

Jonathan


> Signed-off-by: Marcin Bis <marcin@bis-linux.com>
> ---
>  .../bindings/iio/dac/adi,ad5337.yaml          | 48 +++++++++++++++++++
>  MAINTAINERS                                   |  1 +
>  2 files changed, 49 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/iio/dac/adi,ad5337.yaml
> 
> diff --git a/Documentation/devicetree/bindings/iio/dac/adi,ad5337.yaml b/Documentation/devicetree/bindings/iio/dac/adi,ad5337.yaml
> new file mode 100644
> index 000000000000..327a45ccfe4a
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/dac/adi,ad5337.yaml
> @@ -0,0 +1,48 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/iio/dac/adi,ad5337.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Analog Devices AD5337 I2C DAC
> +
> +maintainers:
> +  - Marcin Bis <marcin@bis-linux.com>
> +
> +description:
> +  Binding for the AD5337 dual 8-bit I2C voltage-output DAC.
> +  This part uses the pointer-byte protocol and is not compatible with
> +  the AD5337R nanoDAC+ driver (adi,ad5337r).
> +
> +properties:
> +  compatible:
> +    const: adi,ad5337
> +
> +  reg:
> +    maxItems: 1
> +    description:
> +      7-bit I2C address. 0x0c when A0 is low, 0x0d when A0 is high.
> +
> +  vcc-supply:
> +    description: DAC reference voltage supply.
> +
> +required:
> +  - compatible
> +  - reg
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    i2c {
> +      #address-cells = <1>;
> +      #size-cells = <0>;
> +
> +      dac@0c {
> +        compatible = "adi,ad5337";
> +        reg = <0x0c>;
> +        vcc-supply = <&dac_3v3>;
> +      };
> +    };
> +
> +...
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 614589b6efa4..f967c18fe730 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -441,6 +441,7 @@ F:	drivers/regulator/ad5398.c
>  AD5337  ANALOG DEVICES INC AD5337 DAC DRIVER
>  M:	Marcin Bis <marcin@bis-linux.com>
>  S:	Maintained
> +F:	Documentation/devicetree/bindings/iio/dac/adi,ad5337.yaml
>  F:	drivers/iio/dac/ad5337.c
>  
>  AD5446	ANALOG DEVICES INC AD5446 DAC DRIVER

Re: [PATCH 1/2] iio: dac: ad5337: Add driver for the AD5337 DAC

[Joshua Crofts]

On Fri, 12 Jun 2026 15:31:21 +0200
Marcin Bis <marcin@bis-linux.com> wrote:

> Add driver for the AD5337 dual 8-bit I2C voltage-output DAC.
> This part uses the pointer-byte protocol and is not compatible with
> the AD5337R nanoDAC+ driver (adi,ad5337r).
> 
> Signed-off-by: Marcin Bis <marcin@bis-linux.com>
> ---
>  MAINTAINERS              |   5 ++
>  drivers/iio/dac/Kconfig  |  12 ++-
>  drivers/iio/dac/Makefile |   1 +
>  drivers/iio/dac/ad5337.c | 159 +++++++++++++++++++++++++++++++++++++++
>  4 files changed, 176 insertions(+), 1 deletion(-)
>  create mode 100644 drivers/iio/dac/ad5337.c
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index e035a3be797c..614589b6efa4 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -438,6 +438,11 @@ W:	http://wiki.analog.com/AD5398
>  W:	https://ez.analog.com/linux-software-drivers
>  F:	drivers/regulator/ad5398.c
>  
> +AD5337  ANALOG DEVICES INC AD5337 DAC DRIVER
> +M:	Marcin Bis <marcin@bis-linux.com>
> +S:	Maintained
> +F:	drivers/iio/dac/ad5337.c

Once you reorder your patches, this should go into the (first)
dt-binding patch.

> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Analog Devices AD5337 I2C DAC driver
> + *
> + * Copyright 2017 Marcin Bis <marcin@bis-linux.com>
> + */
> +
> +#include <linux/i2c.h>
> +#include <linux/module.h>
> +#include <linux/mutex.h>
> +#include <linux/regulator/consumer.h>

You're definitely missing array_size.h, types.h, mod_devicetable.h
and err.h.

> +#include <linux/iio/iio.h>
> +
> +#define AD5337_NUM_CHANNELS	2
> +#define AD5337_RESOLUTION	8
> +/*
> + * AD5338 - 10bit, AD5339 - 12bit
> + */

This comment can just be on one line.

> +
> +#define AD5337_PTR_DAC_A	0x01
> +#define AD5337_PTR_DAC_B	0x02
> +
> +struct ad5337_state {
> +	struct i2c_client *client;
> +	struct mutex lock;

Add a comment on why you need a mutex.

> +	unsigned int vref_mv;
> +	u8 cache[AD5337_NUM_CHANNELS];
> +};
> +
> +static int ad5337_write_dac(struct ad5337_state *st, int channel, u8 value)
> +{
> +	u8 buf[3];
> +	int ret;
> +
> +	if (channel)
> +		buf[0] = AD5337_PTR_DAC_B;
> +	else
> +		buf[0] = AD5337_PTR_DAC_A;
> +
> +	/* PD1=0, PD0=0, CLR=1, LDAC=0, D[7:4] */
> +	buf[1] = 0x20 | (value >> 4);
> +	buf[2] = (value & 0x0f) << 4;

You should definitely use FIELD_GET/FIELD_PREP macros from the 
<linux/bitfield.h> header, it improves readability by a lot!

Also, use macros instead of just defining magic numbers like this.

> +
> +	ret = i2c_master_send(st->client, buf, 3);

Use sizeof(buf) instead of just hardcoding the size.

> +
> +	return (ret < 0) ? ret : (ret == 3 ? 0 : -EIO);

I'd definitely abandon using a terniary operator and just break it into
if statements, on first glance this is really hard to read.

> +}
> +
> +static int ad5337_read_raw(struct iio_dev *indio_dev,
> +			   struct iio_chan_spec const *chan,
> +			   int *val, int *val2, long mask)
> +{
> +	struct ad5337_state *st = iio_priv(indio_dev);
> +
> +	switch (mask) {
> +	case IIO_CHAN_INFO_RAW:
> +		*val = st->cache[chan->channel];
> +		return IIO_VAL_INT;
> +	case IIO_CHAN_INFO_SCALE:
> +		*val = st->vref_mv;
> +		*val2 = AD5337_RESOLUTION;
> +		return IIO_VAL_FRACTIONAL_LOG2;
> +	default:
> +		return -EINVAL;
> +	}
> +}
> +
> +static int ad5337_write_raw(struct iio_dev *indio_dev,
> +			    struct iio_chan_spec const *chan,
> +			    int val, int val2, long mask)
> +{
> +	struct ad5337_state *st = iio_priv(indio_dev);
> +	int ret;
> +
> +	if (mask != IIO_CHAN_INFO_RAW)
> +		return -EINVAL;
> +
> +	if (val < 0 || val > ((1 << AD5337_RESOLUTION) - 1))
> +		return -EINVAL;
> +
> +	mutex_lock(&st->lock);

Consider using the guard(mutex)() macro from cleanup.h, it saves lines
and prevents future developers from accidentally forgetting to release
locks (don't forget to add the header as well though)!

> +	ret = ad5337_write_dac(st, chan->channel, val);
> +	if (!ret)
> +		st->cache[chan->channel] = val;
> +	mutex_unlock(&st->lock);
> +
> +	return ret;
> +}
> +
> +static const struct iio_info ad5337_info = {
> +	.read_raw = ad5337_read_raw,
> +	.write_raw = ad5337_write_raw,
> +};
> +
> +#define AD5337_CHANNEL(_chan) {						\

A very tiny nitpick, but you don't need to align your backslashes when defining
a macro.

> +	.type = IIO_VOLTAGE,						\
> +	.indexed = 1,							\
> +	.output = 1,							\
> +	.channel = (_chan),						\
> +	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),			\
> +	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),		\
> +}
> +
> +static const struct iio_chan_spec ad5337_channels[] = {
> +	AD5337_CHANNEL(0),
> +	AD5337_CHANNEL(1),
> +};
> +
> +static int ad5337_probe(struct i2c_client *client)
> +{
> +	struct ad5337_state *st;
> +	struct iio_dev *indio_dev;

Very much a nit, but swap these lines.

> +	int ret;
> +
> +	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
> +		return -ENODEV;
> +
> +	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*st));
> +	if (!indio_dev)
> +		return -ENOMEM;
> +
> +	st = iio_priv(indio_dev);
> +	st->client = client;
> +	mutex_init(&st->lock);

Use devm_mutex_init().

> +
> +	ret = devm_regulator_get_enable_read_voltage(&client->dev, "vcc");
> +	if (ret < 0 && ret != -ENODEV)
> +		return ret;

Return dev_err_probe() here.

> +
> +	st->vref_mv = ret > 0 ? ret / 1000 : 3300;

More magic numbers. If you're converting units, consider using
macros from <linux/units.h>.

-- 
Kind regards

CJD

Re: [PATCH 1/2] iio: dac: ad5337: Add driver for the AD5337 DAC

[Jonathan Cameron]

On Fri, 12 Jun 2026 15:31:21 +0200
Marcin Bis <marcin@bis-linux.com> wrote:

> Add driver for the AD5337 dual 8-bit I2C voltage-output DAC.
> This part uses the pointer-byte protocol and is not compatible with
> the AD5337R nanoDAC+ driver (adi,ad5337r).

Ah.  Here's the explanation.  Make sure that's in the dt binding patch
description as well!  However, the binding could be shared.
Note that sharing a binding doesn't imply a shared driver.

+CC Fabio who sent the original patch to ad the ad5337r.
Fabio, what was the history of that part?  I can't find any reference to it
any more.

> 
> Signed-off-by: Marcin Bis <marcin@bis-linux.com>
> ---
>  MAINTAINERS              |   5 ++
>  drivers/iio/dac/Kconfig  |  12 ++-
>  drivers/iio/dac/Makefile |   1 +
>  drivers/iio/dac/ad5337.c | 159 +++++++++++++++++++++++++++++++++++++++
>  4 files changed, 176 insertions(+), 1 deletion(-)
>  create mode 100644 drivers/iio/dac/ad5337.c
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index e035a3be797c..614589b6efa4 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -438,6 +438,11 @@ W:	http://wiki.analog.com/AD5398
>  W:	https://ez.analog.com/linux-software-drivers
>  F:	drivers/regulator/ad5398.c
>  
> +AD5337  ANALOG DEVICES INC AD5337 DAC DRIVER
> +M:	Marcin Bis <marcin@bis-linux.com>
> +S:	Maintained
> +F:	drivers/iio/dac/ad5337.c
> +
>  AD5446	ANALOG DEVICES INC AD5446 DAC DRIVER
>  M:	Michael Hennerich <michael.hennerich@analog.com>
>  M:	Nuno Sá <nuno.sa@analog.com>
> diff --git a/drivers/iio/dac/Kconfig b/drivers/iio/dac/Kconfig
> index cd4870b65415..de2bc2ec2269 100644
> --- a/drivers/iio/dac/Kconfig
> +++ b/drivers/iio/dac/Kconfig
> @@ -62,6 +62,16 @@ config AD5064
>  	  To compile this driver as a module, choose M here: the
>  	  module will be called ad5064.
>  
> +config AD5337
> +	tristate "Analog Devices AD5337 I2C DAC"
> +	depends on I2C
> +	help
> +	  Say yes here to build support for the Analog Devices AD5337 dual
> +	  8-bit I2C voltage-output DAC.
> +
> +	  To compile this driver as a module, choose M here: the module will be
> +	  called ad5337.
> +
>  config AD5360
>  	tristate "Analog Devices AD5360/61/62/63/70/71/73 DAC driver"
>  	depends on SPI
> @@ -247,7 +257,7 @@ config AD5696_I2C
>  	depends on I2C
>  	select AD5686
>  	help
> -	  Say yes here to build support for Analog Devices AD5311R, AD5337,
> +	  Say yes here to build support for Analog Devices AD5311R, AD5337R,

Separate patch before this one please.

>  	  AD5338R, AD5671R, AD5673R, AD5675R, AD5677R, AD5691R, AD5692R, AD5693,
>  	  AD5693R, AD5694, AD5694R, AD5695R, AD5696, and AD5696R Digital to
>  	  Analog converters.

> diff --git a/drivers/iio/dac/ad5337.c b/drivers/iio/dac/ad5337.c
> new file mode 100644
> index 000000000000..b983baa203fe
> --- /dev/null
> +++ b/drivers/iio/dac/ad5337.c

> +
> +#include <linux/iio/iio.h>
> +
> +#define AD5337_NUM_CHANNELS	2
> +#define AD5337_RESOLUTION	8
> +/*
> + * AD5338 - 10bit, AD5339 - 12bit
> + */
What is this doing here?  Add support for them
or drop the comment.
> +
> +#define AD5337_PTR_DAC_A	0x01
> +#define AD5337_PTR_DAC_B	0x02
> +
> +struct ad5337_state {
> +	struct i2c_client *client;
> +	struct mutex lock;

Locks needs a comment on what data it is there to protect.

> +	unsigned int vref_mv;
> +	u8 cache[AD5337_NUM_CHANNELS];
> +};


> +
> +static int ad5337_write_raw(struct iio_dev *indio_dev,
> +			    struct iio_chan_spec const *chan,
> +			    int val, int val2, long mask)
> +{
> +	struct ad5337_state *st = iio_priv(indio_dev);
> +	int ret;
> +
> +	if (mask != IIO_CHAN_INFO_RAW)
> +		return -EINVAL;
> +
> +	if (val < 0 || val > ((1 << AD5337_RESOLUTION) - 1))
> +		return -EINVAL;
> +
> +	mutex_lock(&st->lock);

	guard(mutex)(&st->lock);
	ret = ad5337_write_dac(st, chan->channel, val);
	if (ret)
		return ret

	st->cache[chan->channel] = val;

	return 0;

> +	ret = ad5337_write_dac(st, chan->channel, val);
> +	if (!ret)
> +		st->cache[chan->channel] = val;
> +	mutex_unlock(&st->lock);
> +
> +	return ret;
> +}