Re: [PATCH v2] iio: dac: Add support for the AD5592R/AD5593R ADCs/DACs

[Michael Hennerich <michael.hennerich@analog.com>]

On 02/27/2016 06:50 PM, Jonathan Cameron wrote:
> On 25/02/16 13:36, michael.hennerich@analog.com wrote:
>> From: Paul Cercueil <paul.cercueil@analog.com>
>>
>> This patch adds support for the AD5592R (spi) and AD5593R (i2c)
>> ADC/DAC devices.
>>
>> Signed-off-by: Paul Cercueil <paul.cercueil@analog.com>
>> Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
>>
> A few bits inline.
>
> I'll need a gpio review on this (looks fine to me but it does contain
> a gpiochip driver.) Not to mention the question of whether they will
> be happy with a gpio chip hiding in iio (rather than via an mfd with a
> separate driver - which feels like overkill here).
>
> The big question to my mind is whether we can take the view this won't
> be the last multipurpose chip we will see so do we need to sort the
> binding out to make it generic?  It'll be a bit of a pain for you
> but I think we can do it fairly easily.
> (either way I'll also need a device tree ack on this one!)
>
> So then we get into the question of the best way of doing the bindings.
> The gpio approach seems a little limiting for things as flexible as
> this but we should certainly be using their macros where relevant.

Hi Jonathan,

Thanks for the review.

The problem is see is that using GPIOF_OPEN_DRAIN, will simulate OPEN 
DRAIN behaviour only, by configuring the device for input when outputing 
logic high.

In this case the chip does it.

See comments below.


>
> J
>> ---
>>
>> Changes since v1:
>> 	* Fix mutex usage
>> 	* Remove unnecessary NULL pointer guards
>> 	* Add comment explaining the invalid data read
>> 	* AD5593R Remove surplus adc readback
>>
>>   .../devicetree/bindings/iio/dac/ad5592r.txt        |  88 +++
>>   drivers/iio/dac/Kconfig                            |  27 +
>>   drivers/iio/dac/Makefile                           |   3 +
>>   drivers/iio/dac/ad5592r-base.c                     | 675 +++++++++++++++++++++
>>   drivers/iio/dac/ad5592r-base.h                     |  77 +++
>>   drivers/iio/dac/ad5592r.c                          | 164 +++++
>>   drivers/iio/dac/ad5593r.c                          | 131 ++++
>>   include/dt-bindings/iio/adi,ad5592r.h              |  16 +
>>   8 files changed, 1181 insertions(+)
>>   create mode 100644 Documentation/devicetree/bindings/iio/dac/ad5592r.txt
>>   create mode 100644 drivers/iio/dac/ad5592r-base.c
>>   create mode 100644 drivers/iio/dac/ad5592r-base.h
>>   create mode 100644 drivers/iio/dac/ad5592r.c
>>   create mode 100644 drivers/iio/dac/ad5593r.c
>>   create mode 100644 include/dt-bindings/iio/adi,ad5592r.h
>>
>> diff --git a/Documentation/devicetree/bindings/iio/dac/ad5592r.txt b/Documentation/devicetree/bindings/iio/dac/ad5592r.txt
>> new file mode 100644
>> index 0000000..9d7f23a
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/iio/dac/ad5592r.txt
>> @@ -0,0 +1,88 @@
>> +Analog Devices AD5592R/AD5593R DAC/ADC device driver
>> +
>> +Required properties for the AD5592R:
>> +	- compatible: Must be "adi,ad5592r"
>> +	- reg: SPI chip select number for the device
>> +	- spi-max-frequency: Max SPI frequency to use (< 30000000)
>> +	- spi-cpol: The AD5592R requires inverse clock polarity (CPOL) mode
>> +
>> +Required properties for the AD5593R:
>> +	- compatible: Must be "adi,ad5593r"
>> +	- reg: I2C address of the device
>> +
>> +Required properties for all supported chips:
>> +	- channel-modes: An array of eight 8-bit values (one per channel)
>> +	  describing the mode of each channel. Macros specifying the valid values
>> +	  can be found in <dt-bindings/iio/adi,ad5592r.h>.
>> +	  The following values are currently supported:
> Lets think about making this truely generic.
>
> So we have a basic mode questio first.  I think we separate that from the later
> part. Also do we break this down into individual channels?  It think we probably
> do want to like we have done for various highly adapatable adcs in the past.
>
> so we'd have something like:
> 	channels {
> 		#address-cells = <1>;
> 		#size-cells = <0>;
> 		channel@0 {
> 			mode = CH_MODE_ADC,
> 		},
> 		channel@1 {
> 			mode = CH_MODE_DAC,
> 		},
> 		channel@2 {
> 			mode = CH_MODE_DAC_ADC
> 		},
> 		channel@3 {
> 			mode = CH_MODE_UNUSED,
> 			offstate = CH_OFFSTATE_PULLDOWN,
> 		},
> 		channel@4 {
> 			mode = CH_MODE_GPIO,
> 			//lift the opendrain stuff from the gpio bindings macros.	
> 		}
> 			
> Or take something more similar to the gpio bindings perhaps?  bit fiddly here
> as we can have a wide range of stuff and not all of it is always relevant.
>
> Input from others on this most welcome!

Let's go for this.


>
>
> 		}compatible = "regulator-fixed";
>> +		regulator-name = "vref-ad559x";
>> +		regulator-min-microvolt = <3300000>;
>> +		regulator-max-microvolt = <3300000>;
>> +		regulator-always-on;
>> +	};
>> +
>> +	ad5592r@0 {
>> +		compatible = "adi,ad5592r";
>> +		reg = <0>;
>> +		spi-max-frequency = <1000000>;
>> +		spi-cpol;
>> +
>> +		channel-modes = /bits/ 8 <
>> +			CH_MODE_DAC
>> +			CH_MODE_ADC
>> +			CH_MODE_DAC_AND_ADC
>> +			CH_MODE_DAC_AND_ADC
>> +			CH_MODE_UNUSED_PULL_DOWN
>> +			CH_MODE_GPIO
>> +			CH_MODE_GPIO
>> +			CH_MODE_GPIO
>> +		>;
>> +
>> +		vref-supply = <&vref>; /* optional */
>> +		reset-gpios = <&gpio0 86 0>;  /* optional */
>> +	};
>> +
>> +AD5593R Example:
>> +
>> +	#include <dt-bindings/iio/adi,ad5592r.h>
>> +
>> +	ad5593r@10 {
>> +		compatible = "adi,ad5593r";
>> +		reg = <0x10>;
>> +		channel-modes = /bits/ 8 <
>> +			CH_MODE_DAC
>> +			CH_MODE_ADC
>> +			CH_MODE_DAC_AND_ADC
>> +			CH_MODE_DAC_AND_ADC
>> +			CH_MODE_UNUSED_PULL_DOWN
>> +			CH_MODE_GPIO
>> +			CH_MODE_GPIO
>> +			CH_MODE_GPIO
>> +		>;
>> +
>> +	};
>> diff --git a/drivers/iio/dac/Kconfig b/drivers/iio/dac/Kconfig
>> index 31a1985..e7dd376 100644
>> --- a/drivers/iio/dac/Kconfig
>> +++ b/drivers/iio/dac/Kconfig
>> @@ -74,6 +74,33 @@ config AD5449
>>   	  To compile this driver as a module, choose M here: the
>>   	  module will be called ad5449.
>>
>> +config AD5592R_BASE
>> +	tristate
>> +
>> +config AD5592R
>> +	tristate "Analog Devices AD5592R ADC/DAC driver"
>> +	depends on SPI_MASTER
>> +	depends on OF
>> +	select AD5592R_BASE
>> +	help
>> +	  Say yes here to build support for Analog Devices AD5592R
>> +	  Digital to Analog / Analog to Digital Converter.
>> +
>> +	  To compile this driver as a module, choose M here: the
>> +	  module will be called ad5592r.
>> +
>> +config AD5593R
>> +	tristate "Analog Devices AD5593R ADC/DAC driver"
>> +	depends on I2C
>> +	depends on OF
>> +	select AD5592R_BASE
>> +	help
>> +	  Say yes here to build support for Analog Devices AD5593R
>> +	  Digital to Analog / Analog to Digital Converter.
>> +
>> +	  To compile this driver as a module, choose M here: the
>> +	  module will be called ad5593r.
>> +
>>   config AD5504
>>   	tristate "Analog Devices AD5504/AD5501 DAC SPI driver"
>>   	depends on SPI
>> diff --git a/drivers/iio/dac/Makefile b/drivers/iio/dac/Makefile
>> index e2deda9..cf23310 100644
>> --- a/drivers/iio/dac/Makefile
>> +++ b/drivers/iio/dac/Makefile
>> @@ -11,6 +11,9 @@ obj-$(CONFIG_AD5064) += ad5064.o
>>   obj-$(CONFIG_AD5504) += ad5504.o
>>   obj-$(CONFIG_AD5446) += ad5446.o
>>   obj-$(CONFIG_AD5449) += ad5449.o
>> +obj-$(CONFIG_AD5592R_BASE) += ad5592r-base.o
>> +obj-$(CONFIG_AD5592R) += ad5592r.o
>> +obj-$(CONFIG_AD5593R) += ad5593r.o
>>   obj-$(CONFIG_AD5755) += ad5755.o
>>   obj-$(CONFIG_AD5761) += ad5761.o
>>   obj-$(CONFIG_AD5764) += ad5764.o
>> diff --git a/drivers/iio/dac/ad5592r-base.c b/drivers/iio/dac/ad5592r-base.c
>> new file mode 100644
>> index 0000000..6dd4eab
>> --- /dev/null
>> +++ b/drivers/iio/dac/ad5592r-base.c
>> @@ -0,0 +1,675 @@
>> +/*
>> + * AD5592R Digital <-> Analog converters driver
>> + *
>> + * Copyright 2014-2016 Analog Devices Inc.
>> + * Author: Paul Cercueil <paul.cercueil@analog.com>
>> + *
>> + * Licensed under the GPL-2.
>> + */
>> +
>> +#include <linux/bitops.h>
>> +#include <linux/delay.h>
>> +#include <linux/iio/iio.h>
>> +#include <linux/module.h>
>> +#include <linux/mutex.h>
>> +#include <linux/of.h>
>> +#include <linux/regulator/consumer.h>
>> +#include <linux/gpio/consumer.h>
>> +#include <linux/gpio/driver.h>
>> +#include <linux/gpio.h>
>> +
>> +#include <dt-bindings/iio/adi,ad5592r.h>
>> +
>> +#include "ad5592r-base.h"
>> +
>> +#ifdef CONFIG_GPIOLIB
>> +
>> +static int ad5592r_gpio_get(struct gpio_chip *chip, unsigned offset)
>> +{
>> +	struct ad5592r_state *st = gpiochip_get_data(chip);
>> +	int ret = 0;
>> +	u8 val;
>> +
>> +	mutex_lock(&st->gpio_lock);
>> +
>> +	if (st->gpio_out & BIT(offset))
>> +		val = st->gpio_val;
>> +	else
>> +		ret = st->ops->gpio_read(st, &val);
>> +
>> +	mutex_unlock(&st->gpio_lock);
>> +
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	return !!(val & BIT(offset));
>> +}
>> +
>> +static void ad5592r_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
>> +{
>> +	struct ad5592r_state *st = gpiochip_get_data(chip);
>> +
>> +	mutex_lock(&st->gpio_lock);
>> +
>> +	if (value)
>> +		st->gpio_val |= BIT(offset);
>> +	else
>> +		st->gpio_val &= ~BIT(offset);
>> +
>> +	st->ops->reg_write(st, AD5592R_REG_GPIO_SET, st->gpio_val);
>> +
>> +	mutex_unlock(&st->gpio_lock);
>> +}
>> +
>> +static int ad5592r_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
>> +{
>> +	struct ad5592r_state *st = gpiochip_get_data(chip);
>> +	int ret;
>> +
>> +	mutex_lock(&st->gpio_lock);
>> +
>> +	st->gpio_out &= ~BIT(offset);
>> +	st->gpio_in |= BIT(offset);
>> +
>> +	ret = st->ops->reg_write(st, AD5592R_REG_GPIO_OUT_EN, st->gpio_out);
>> +	if (ret < 0)
>> +		goto err_unlock;
>> +
>> +	ret = st->ops->reg_write(st, AD5592R_REG_GPIO_IN_EN, st->gpio_in);
>> +
>> +err_unlock:
>> +	mutex_unlock(&st->gpio_lock);
>> +
>> +	return ret;
>> +}
>> +
>> +static int ad5592r_gpio_direction_output(struct gpio_chip *chip,
>> +					 unsigned offset, int value)
>> +{
>> +	struct ad5592r_state *st = gpiochip_get_data(chip);
>> +	int ret;
>> +
>> +	mutex_lock(&st->gpio_lock);
>> +
>> +	if (value)
>> +		st->gpio_val |= BIT(offset);
>> +	else
>> +		st->gpio_val &= ~BIT(offset);
>> +
>> +	st->gpio_in &= ~BIT(offset);
>> +	st->gpio_out |= BIT(offset);
>> +
>> +	ret = st->ops->reg_write(st, AD5592R_REG_GPIO_SET, st->gpio_val);
>> +	if (ret < 0)
>> +		goto err_unlock;
>> +
>> +	ret = st->ops->reg_write(st, AD5592R_REG_GPIO_OUT_EN, st->gpio_out);
>> +	if (ret < 0)
>> +		goto err_unlock;
>> +
>> +	ret = st->ops->reg_write(st, AD5592R_REG_GPIO_IN_EN, st->gpio_in);
>> +
>> +err_unlock:
>> +	mutex_unlock(&st->gpio_lock);
>> +
>> +	return ret;
>> +}
>> +
>> +static int ad5592r_gpio_request(struct gpio_chip *chip, unsigned offset)
>> +{
>> +	struct ad5592r_state *st = gpiochip_get_data(chip);
>> +
>> +	if (!(st->gpio_map & BIT(offset))) {
>> +		dev_err(st->dev, "GPIO %d is reserved by alternate function\n",
>> +			offset);
>> +		return -ENODEV;
>> +	}
>> +
>> +	if (offset >= chip->ngpio)
>> +		return -EINVAL;
>> +
>> +	return 0;
>> +}
>> +
>> +static int ad5592r_gpio_init(struct ad5592r_state *st)
>> +{
>> +	st->gpiochip.label = dev_name(st->dev);
>> +	st->gpiochip.base = -1;
>> +	st->gpiochip.ngpio = 8;
>> +	st->gpiochip.parent = st->dev;
>> +	st->gpiochip.can_sleep = true;
>> +	st->gpiochip.direction_input = ad5592r_gpio_direction_input;
>> +	st->gpiochip.direction_output = ad5592r_gpio_direction_output;
>> +	st->gpiochip.get = ad5592r_gpio_get;
>> +	st->gpiochip.set = ad5592r_gpio_set;
>> +	st->gpiochip.request = ad5592r_gpio_request;
>> +	st->gpiochip.owner = THIS_MODULE;
>> +
>> +	mutex_init(&st->gpio_lock);
>> +
>> +	return gpiochip_add_data(&st->gpiochip, st);
>> +}
>> +
>> +static void ad5592r_gpio_cleanup(struct ad5592r_state *st)
>> +{
>> +	gpiochip_remove(&st->gpiochip);
>> +}
>> +#else
>> +static int ad5592r_gpio_init(struct ad5592r_state *st) { return 0 };
>> +static void ad5592r_gpio_cleanup(struct ad5592r_state *st) { };
>> +#endif /* CONFIG_GPIOLIB */
>> +
>> +static int ad5592r_reset(struct ad5592r_state *st)
>> +{
>> +	struct gpio_desc *gpio;
>> +	struct iio_dev *iio_dev = iio_priv_to_dev(st);
>> +
>> +	gpio = devm_gpiod_get_optional(st->dev, "reset", GPIOD_OUT_LOW);
>> +	if (IS_ERR(gpio))
>> +		return PTR_ERR(gpio);
>> +
>> +	if (gpio) {
>> +		udelay(1);
>> +		gpiod_set_value(gpio, 1);
>> +	} else {
>> +		mutex_lock(&iio_dev->mlock);
>> +		st->ops->reg_write(st, AD5592R_REG_RESET, 0xdac);
>> +		mutex_unlock(&iio_dev->mlock);
>> +	}
>> +
>> +	udelay(250);
>> +
>> +	return 0;
>> +}
>> +
>> +static int ad5592r_get_vref(struct ad5592r_state *st)
>> +{
>> +	int ret;
>> +
>> +	if (st->reg) {
>> +		ret = regulator_get_voltage(st->reg);
>> +		if (ret < 0)
>> +			return ret;
>> +
>> +		return ret / 1000;
>> +	} else {
>> +		return 2500;
>> +	}
>> +}
>> +
>> +static int ad5592r_set_channel_modes(struct ad5592r_state *st)
>> +{
>> +	const struct ad5592r_rw_ops *ops = st->ops;
>> +	int ret;
>> +	unsigned i;
>> +	struct iio_dev *iio_dev = iio_priv_to_dev(st);
>> +	u8 pulldown = 0, open_drain = 0, tristate = 0,
>> +	   dac = 0, adc = 0;
>> +	u16 read_back;
>> +
>> +	for (i = 0; i < st->num_channels; i++) {
>> +		switch (st->channel_modes[i]) {
>> +		case CH_MODE_DAC:
>> +			dac |= BIT(i);
>> +			break;
>> +
>> +		case CH_MODE_ADC:
>> +			adc |= BIT(i);
>> +			break;
>> +
>> +		case CH_MODE_DAC_AND_ADC:
>> +			dac |= BIT(i);
>> +			adc |= BIT(i);
>> +			break;
>> +
>> +		case CH_MODE_UNUSED_PULL_DOWN:
>> +			pulldown |= BIT(i);
>> +			break;
>> +
>> +		case CH_MODE_UNUSED_OUT_TRISTATE:
>> +			tristate |= BIT(i);
>> +			break;
>> +
>> +		case CH_MODE_UNUSED_OUT_LOW:
>> +			st->gpio_out |= BIT(i);
>> +			break;
>> +
>> +		case CH_MODE_UNUSED_OUT_HIGH:
>> +			st->gpio_out |= BIT(i);
>> +			st->gpio_val |= BIT(i);
>> +			break;
>> +
>> +		case CH_MODE_GPIO_OPEN_DRAIN:
>> +			open_drain |= BIT(i);
>> +
>> +			/* fall-through */
>> +
>> +		case CH_MODE_GPIO:
>> +			st->gpio_map |= BIT(i);
>> +			st->gpio_in |= BIT(i); /* Default to input */
>> +			break;
>> +
>> +		default:
>> +			pulldown |= BIT(i);
>> +			break;
>> +		}
>> +	}
>> +
>> +	mutex_lock(&iio_dev->mlock);
>> +
>> +	/* Pull down unused pins to GND */
>> +	ret = ops->reg_write(st, AD5592R_REG_PULLDOWN, pulldown);
>> +	if (ret)
>> +		goto err_unlock;
>> +
>> +	ret = ops->reg_write(st, AD5592R_REG_TRISTATE, tristate);
>> +	if (ret)
>> +		goto err_unlock;
>> +
>> +	/* Configure pins that we use */
>> +	ret = ops->reg_write(st, AD5592R_REG_DAC_EN, dac);
>> +	if (ret)
>> +		goto err_unlock;
>> +
>> +	ret = ops->reg_write(st, AD5592R_REG_ADC_EN, adc);
>> +	if (ret)
>> +		goto err_unlock;
>> +
>> +	ret = ops->reg_write(st, AD5592R_REG_OPEN_DRAIN, open_drain);
>> +	if (ret)
>> +		goto err_unlock;
>> +
>> +	ret = ops->reg_write(st, AD5592R_REG_GPIO_SET, st->gpio_val);
>> +	if (ret)
>> +		goto err_unlock;
>> +
>> +	ret = ops->reg_write(st, AD5592R_REG_GPIO_OUT_EN, st->gpio_out);
>> +	if (ret)
>> +		goto err_unlock;
>> +
>> +	ret = ops->reg_write(st, AD5592R_REG_GPIO_IN_EN, st->gpio_in);
>> +	if (ret)
>> +		goto err_unlock;
>> +
>> +	/* Verify that we can read back at least one register */
>> +	ret = ops->reg_read(st, AD5592R_REG_ADC_EN, &read_back);
>> +	if (!ret && (read_back & 0xff) != adc)
>> +		ret = -EIO;
>> +
>> +err_unlock:
>> +	mutex_unlock(&iio_dev->mlock);
>> +	return ret;
>> +}
>> +
>> +static int ad5592r_write_raw(struct iio_dev *iio_dev,
>> +	struct iio_chan_spec const *chan, int val, int val2, long mask)
>> +{
>> +	struct ad5592r_state *st = iio_priv(iio_dev);
>> +	int ret;
>> +
>> +	switch (mask) {
>> +	case IIO_CHAN_INFO_RAW:
>> +		if (val >= (1 << chan->scan_type.realbits) || val < 0)
>> +			return -EINVAL;
>> +
>> +		/* Warn if we try to write to a ADC channel */
>> +		WARN_ON(!chan->output);
> Probably just wants to return an error rather than filling the logs.
> People do silly things all time like that.

ok

>> +
>> +		mutex_lock(&iio_dev->mlock);
>> +		ret = st->ops->write_dac(st, chan->channel, val);
>> +		if (!ret)
>> +			st->cached_dac[chan->channel] = val;
>> +		mutex_unlock(&iio_dev->mlock);
>> +		return ret;
>> +	case IIO_CHAN_INFO_SCALE:
>> +		if (chan->type == IIO_VOLTAGE) {
>> +			bool gain;
>> +
>> +			if (val == st->scale_avail[0][0] &&
>> +				val2 == st->scale_avail[0][1])
>> +				gain = false;
>> +			else if (val == st->scale_avail[1][0] &&
>> +				 val2 == st->scale_avail[1][1])
>> +				gain = true;
>> +			else
>> +				return -EINVAL;
>> +
>> +			mutex_lock(&iio_dev->mlock);
>> +
>> +			ret = st->ops->reg_read(st, AD5592R_REG_CTRL,
>> +						&st->cached_gp_ctrl);
>> +			if (ret < 0) {
>> +				mutex_unlock(&iio_dev->mlock);
>> +				return ret;
>> +			}
>> +
>> +			if (chan->output) {
>> +				if (gain)
>> +					st->cached_gp_ctrl |=
>> +						AD5592R_REG_CTRL_DAC_RANGE;
>> +				else
>> +					st->cached_gp_ctrl &=
>> +						~AD5592R_REG_CTRL_DAC_RANGE;
>> +			} else {
>> +				if (gain)
>> +					st->cached_gp_ctrl |=
>> +						AD5592R_REG_CTRL_ADC_RANGE;
>> +				else
>> +					st->cached_gp_ctrl &=
>> +						~AD5592R_REG_CTRL_ADC_RANGE;
>> +			}
>> +
>> +			ret = st->ops->reg_write(st, AD5592R_REG_CTRL,
>> +						 st->cached_gp_ctrl);
>> +			mutex_unlock(&iio_dev->mlock);
>> +			if (ret < 0)
>> +				return ret;
>> +
>> +			return ret;
>> +
>> +		}
>> +		break;
>> +	default:
>> +		return -EINVAL;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int ad5592r_read_raw(struct iio_dev *iio_dev,
>> +			   struct iio_chan_spec const *chan,
>> +			   int *val, int *val2, long m)
>> +{
>> +	struct ad5592r_state *st = iio_priv(iio_dev);
>> +	u16 read_val;
>> +	int ret;
>> +
>> +	mutex_lock(&iio_dev->mlock);
> Move the lock into the switch statement as it doesn't
> need to be held for a fair bit of the code below (such as the scale read
> backs).

ok

>> +
>> +	switch (m) {
>> +	case IIO_CHAN_INFO_RAW:
>> +
>> +		if (!chan->output) {
>> +			ret = st->ops->read_adc(st, chan->channel, &read_val);
>> +			if (ret)
>> +				goto unlock;
>> +
>> +			if ((read_val >> 12 & 0x7) != (chan->channel & 0x7)) {
>> +				dev_err(st->dev, "Error while reading channel %u\n",
>> +						chan->channel);
>> +				ret = -EIO;
>> +				goto unlock;
>> +			}
>> +
>> +			read_val &= GENMASK(11, 0);
>> +
>> +		} else {
>> +			read_val = st->cached_dac[chan->channel];
>> +		}
>> +
>> +		dev_dbg(st->dev, "Channel %u read: 0x%04hX\n",
>> +				chan->channel, read_val);
>> +
>> +		*val = (int) read_val;
>> +		ret = IIO_VAL_INT;
>> +		break;
>> +	case IIO_CHAN_INFO_SCALE:
>> +
>> +		*val = ad5592r_get_vref(st);
>> +
>> +		if (chan->type == IIO_TEMP) {
>> +			s64 tmp = *val * (3767897513LL / 25LL);
>> +			*val = div_s64_rem(tmp, 1000000000LL, val2);
>> +
>> +			ret = IIO_VAL_INT_PLUS_MICRO;
>> +		} else {
>> +			int mult;
>> +
>> +			if (chan->output)
>> +				mult = !!(st->cached_gp_ctrl &
>> +					AD5592R_REG_CTRL_DAC_RANGE);
>> +			else
>> +				mult = !!(st->cached_gp_ctrl &
>> +					AD5592R_REG_CTRL_ADC_RANGE);
>> +
>> +			*val *= ++mult;
>> +
>> +			*val2 = chan->scan_type.realbits;
>> +			ret = IIO_VAL_FRACTIONAL_LOG2;
>> +		}
>> +		break;
>> +	case IIO_CHAN_INFO_OFFSET:
>> +
>> +		ret = ad5592r_get_vref(st);
>> +
>> +		if (st->cached_gp_ctrl & AD5592R_REG_CTRL_ADC_RANGE)
>> +			*val = (-34365 * 25) / ret;
>> +		else
>> +			*val = (-75365 * 25) / ret;
>> +		ret =  IIO_VAL_INT;
>> +		break;
>> +	default:
>> +		ret = -EINVAL;
>> +	}
>> +
>> +unlock:
>> +	mutex_unlock(&iio_dev->mlock);
>> +	return ret;
>> +}
>> +
>> +static int ad5592r_write_raw_get_fmt(struct iio_dev *indio_dev,
>> +				 struct iio_chan_spec const *chan, long mask)
>> +{
>> +	switch (mask) {
>> +	case IIO_CHAN_INFO_SCALE:
>> +		return IIO_VAL_INT_PLUS_NANO;
>> +
>> +	default:
>> +		return IIO_VAL_INT_PLUS_MICRO;
>> +	}
>> +
>> +	return -EINVAL;
>> +}
>> +
>> +static const struct iio_info ad5592r_info = {
>> +	.read_raw = ad5592r_read_raw,
>> +	.write_raw = ad5592r_write_raw,
>> +	.write_raw_get_fmt = ad5592r_write_raw_get_fmt,
>> +	.driver_module = THIS_MODULE,
>> +};
>> +
>> +static ssize_t ad5592r_show_scale_available(struct iio_dev *iio_dev,
>> +					   uintptr_t private,
>> +					   const struct iio_chan_spec *chan,
>> +					   char *buf)
>> +{
>> +	struct ad5592r_state *st = iio_priv(iio_dev);
>> +
>> +	return sprintf(buf, "%d.%09u %d.%09u\n",
>> +		st->scale_avail[0][0], st->scale_avail[0][1],
>> +		st->scale_avail[1][0], st->scale_avail[1][1]);
>> +}
>> +
>> +static struct iio_chan_spec_ext_info ad5592r_ext_info[] = {
>> +	{
>> +	 .name = "scale_available",
>> +	 .read = ad5592r_show_scale_available,
>> +	 .shared = true,
>> +	 },
>> +	{},
>> +};
>> +
>> +static void ad5592r_setup_channel(struct iio_dev *iio_dev,
>> +		struct iio_chan_spec *chan, bool output, unsigned id)
>> +{
>> +	chan->type = IIO_VOLTAGE;
>> +	chan->indexed = 1;
>> +	chan->output = output;
>> +	chan->channel = id;
>> +	chan->info_mask_separate = BIT(IIO_CHAN_INFO_RAW);
>> +	chan->info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE);
>> +	chan->scan_type.sign = 'u';
>> +	chan->scan_type.realbits = 12;
>> +	chan->scan_type.storagebits = 16;
>> +	chan->ext_info = ad5592r_ext_info;
>> +}
>> +
>> +static int ad5592r_alloc_channels(struct ad5592r_state *st)
>> +{
>> +	unsigned i, curr_channel = 0,
>> +		 num_channels = st->num_channels;
>> +	struct iio_dev *iio_dev = iio_priv_to_dev(st);
>> +	struct iio_chan_spec *channels;
>> +	int ret;
>> +
>> +	ret = device_property_read_u8_array(st->dev, "channel-modes",
>> +			st->channel_modes, num_channels);
>> +	if (ret)
>> +		return ret;
>> +
>> +	channels = devm_kzalloc(st->dev,
>> +			(1 + 2 * num_channels) * sizeof(*channels), GFP_KERNEL);
>> +	if (!channels)
>> +		return -ENOMEM;
>> +
>> +	for (i = 0; i < num_channels; i++) {
>> +		switch (st->channel_modes[i]) {
>> +		case CH_MODE_DAC:
>> +			ad5592r_setup_channel(iio_dev, &channels[curr_channel],
>> +					true, i);
>> +			curr_channel++;
>> +			break;
>> +
>> +		case CH_MODE_ADC:
>> +			ad5592r_setup_channel(iio_dev, &channels[curr_channel],
>> +					false, i);
>> +			curr_channel++;
>> +			break;
>> +
>> +		case CH_MODE_DAC_AND_ADC:
>> +			ad5592r_setup_channel(iio_dev, &channels[curr_channel],
>> +					true, i);
>> +			curr_channel++;
>> +			ad5592r_setup_channel(iio_dev, &channels[curr_channel],
>> +					false, i);
>> +			curr_channel++;
>> +			break;
>> +
>> +		default:
>> +			continue;
>> +		}
>> +	}
>> +
>> +	channels[curr_channel].type = IIO_TEMP;
>> +	channels[curr_channel].channel = 8;
>> +	channels[curr_channel].info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
>> +				   BIT(IIO_CHAN_INFO_SCALE) |
>> +				   BIT(IIO_CHAN_INFO_OFFSET);
>> +	curr_channel++;
>> +
>> +	iio_dev->num_channels = curr_channel;
>> +	iio_dev->channels = channels;
>> +
>> +	return 0;
>> +}
>> +
>> +static void ad5592r_init_scales(struct ad5592r_state *st, int vref_mV)
>> +{
>> +	s64 tmp = (s64)vref_mV * 1000000000LL >> 12;
>> +
>> +	st->scale_avail[0][0] =
>> +		div_s64_rem(tmp, 1000000000LL, &st->scale_avail[0][1]);
>> +	st->scale_avail[1][0] =
>> +		div_s64_rem(tmp * 2, 1000000000LL, &st->scale_avail[1][1]);
>> +}
>> +
>> +int ad5592r_probe(struct device *dev, const char *name,
>> +		const struct ad5592r_rw_ops *ops)
>> +{
>> +	struct iio_dev *iio_dev;
>> +	struct ad5592r_state *st;
>> +	int ret;
>> +
>> +	iio_dev = devm_iio_device_alloc(dev, sizeof(*st));
>> +	if (!iio_dev)
>> +		return -ENOMEM;
>> +
>> +	st = iio_priv(iio_dev);
>> +	st->dev = dev;
>> +	st->ops = ops;
>> +	st->num_channels = 8;
>> +	dev_set_drvdata(dev, iio_dev);
>> +
>> +	st->reg = devm_regulator_get_optional(dev, "vref");
>> +	if (IS_ERR(st->reg)) {
>> +		if ((PTR_ERR(st->reg) != -ENODEV) && dev->of_node)
>> +			return PTR_ERR(st->reg);
>> +
>> +		st->reg = NULL;
>> +	} else {
>> +		ret = regulator_enable(st->reg);
>> +		if (ret)
>> +			return ret;
>> +	}
>> +
>> +	iio_dev->dev.parent = dev;
>> +	iio_dev->name = name;
>> +	iio_dev->info = &ad5592r_info;
>> +	iio_dev->modes = INDIO_DIRECT_MODE;
>> +
>> +	ad5592r_init_scales(st, ad5592r_get_vref(st));
>> +
>> +	ret = ad5592r_reset(st);
>> +	if (ret)
>> +		goto error_disable_reg;
>> +
>> +	ret = ops->reg_write(st, AD5592R_REG_PD,
>> +		     (st->reg == NULL) ? AD5592R_REG_PD_EN_REF : 0);
>> +	if (ret)
>> +		goto error_disable_reg;
>> +
>> +	ret = ad5592r_alloc_channels(st);
>> +	if (ret)
>> +		goto error_disable_reg;
>> +
>> +	ret = ad5592r_set_channel_modes(st);
>> +	if (ret)
>> +		goto error_disable_reg;
>> +
>> +	ret = devm_iio_device_register(dev, iio_dev);
>> +	if (ret)
>> +		goto error_disable_reg;
> If you use a managed iio_device_register here it will only
> be unregistered after the end of the remove function.  It certainly looks
> like it really wants to be done at the start of the remove function
> so as to remove the exposed interfaces (user and in kernel) before changing
> the channel modes etc.
>
> Hence use the unmanaged version and iio_device_unregister in the remove.

I go for the unmanged version in both cases.

>> +
>> +	return ad5592r_gpio_init(st);
>> +
>> +error_disable_reg:
>> +	if (st->reg)
>> +		regulator_disable(st->reg);
>> +
>> +	return ret;
>> +}
>> +EXPORT_SYMBOL_GPL(ad5592r_probe);
>> +
>> +int ad5592r_remove(struct device *dev)
>> +{
>> +	struct iio_dev *iio_dev = dev_get_drvdata(dev);
>> +	struct ad5592r_state *st = iio_priv(iio_dev);
>> +	unsigned int i;
>> +
>> +	/* Reset all channels */
>> +	for (i = 0; i < ARRAY_SIZE(st->channel_modes); i++)
>> +		st->channel_modes[i] = CH_MODE_UNUSED_PULL_DOWN;
>> +
>> +	if (st->reg)
>> +		regulator_disable(st->reg);
>> +
>> +	if (st->gpio_map)
>> +		ad5592r_gpio_cleanup(st);
>> +
>> +	return ad5592r_set_channel_modes(st);
>> +}
>> +EXPORT_SYMBOL_GPL(ad5592r_remove);
>> +
>> +MODULE_AUTHOR("Paul Cercueil <paul.cercueil@analog.com>");
>> +MODULE_DESCRIPTION("Analog Devices AD5592R multi-channel converters");
>> +MODULE_LICENSE("GPL v2");
>> diff --git a/drivers/iio/dac/ad5592r-base.h b/drivers/iio/dac/ad5592r-base.h
>> new file mode 100644
>> index 0000000..162e833
>> --- /dev/null
>> +++ b/drivers/iio/dac/ad5592r-base.h
>> @@ -0,0 +1,77 @@
>> +/*
>> + * AD5592R / AD5593R Digital <-> Analog converters driver
>> + *
>> + * Copyright 2015-2016 Analog Devices Inc.
>> + * Author: Paul Cercueil <paul.cercueil@analog.com>
>> + *
>> + * Licensed under the GPL-2.
>> + */
>> +
>> +#ifndef __DRIVERS_IIO_DAC_AD5592R_BASE_H__
>> +#define __DRIVERS_IIO_DAC_AD5592R_BASE_H__
>> +
>> +#include <linux/types.h>
>> +#include <linux/cache.h>
>> +#include <linux/mutex.h>
>> +#include <linux/gpio/driver.h>
>> +
>> +struct device;
>> +struct ad5592r_state;
>> +
>> +enum ad5592r_registers {
>> +	AD5592R_REG_NOOP		= 0x0,
>> +	AD5592R_REG_DAC_READBACK	= 0x1,
>> +	AD5592R_REG_ADC_SEQ		= 0x2,
>> +	AD5592R_REG_CTRL		= 0x3,
>> +	AD5592R_REG_ADC_EN		= 0x4,
>> +	AD5592R_REG_DAC_EN		= 0x5,
>> +	AD5592R_REG_PULLDOWN		= 0x6,
>> +	AD5592R_REG_LDAC		= 0x7,
>> +	AD5592R_REG_GPIO_OUT_EN		= 0x8,
>> +	AD5592R_REG_GPIO_SET		= 0x9,
>> +	AD5592R_REG_GPIO_IN_EN		= 0xA,
>> +	AD5592R_REG_PD			= 0xB,
>> +	AD5592R_REG_OPEN_DRAIN		= 0xC,
>> +	AD5592R_REG_TRISTATE		= 0xD,
>> +	AD5592R_REG_RESET		= 0xF,
>> +};
>> +
>> +#define AD5592R_REG_PD_EN_REF		BIT(9)
>> +#define AD5592R_REG_CTRL_ADC_RANGE	BIT(5)
>> +#define AD5592R_REG_CTRL_DAC_RANGE	BIT(4)
>> +
>> +struct ad5592r_rw_ops {
>> +	int (*write_dac)(struct ad5592r_state *st, unsigned chan, u16 value);
>> +	int (*read_adc)(struct ad5592r_state *st, unsigned chan, u16 *value);
>> +	int (*reg_write)(struct ad5592r_state *st, u8 reg, u16 value);
>> +	int (*reg_read)(struct ad5592r_state *st, u8 reg, u16 *value);
>> +	int (*gpio_read)(struct ad5592r_state *st, u8 *value);
>> +};
>> +
>> +struct ad5592r_state {
>> +	struct device *dev;
>> +	struct regulator *reg;
>> +#ifdef CONFIG_GPIOLIB
>> +	struct gpio_chip gpiochip;
>> +	struct mutex gpio_lock;	/* Protect cached gpio_out, gpio_val, etc. */
>> +#endif
>> +	unsigned int num_channels;
>> +	const struct ad5592r_rw_ops *ops;
>> +	int scale_avail[2][2];
>> +	u16 cached_dac[8];
>> +	u16 cached_gp_ctrl;
>> +	u8 channel_modes[8];
>> +	u8 gpio_map;
>> +	u8 gpio_out;
>> +	u8 gpio_in;
>> +	u8 gpio_val;
>> +
>> +	__be16 spi_msg ____cacheline_aligned;
>> +	__be16 spi_msg_nop;
>> +};
>> +
>> +int ad5592r_probe(struct device *dev, const char *name,
>> +		const struct ad5592r_rw_ops *ops);
>> +int ad5592r_remove(struct device *dev);
>> +
>> +#endif /* __DRIVERS_IIO_DAC_AD5592R_BASE_H__ */
>> diff --git a/drivers/iio/dac/ad5592r.c b/drivers/iio/dac/ad5592r.c
>> new file mode 100644
>> index 0000000..0b235a2
>> --- /dev/null
>> +++ b/drivers/iio/dac/ad5592r.c
>> @@ -0,0 +1,164 @@
>> +/*
>> + * AD5592R Digital <-> Analog converters driver
>> + *
>> + * Copyright 2015-2016 Analog Devices Inc.
>> + * Author: Paul Cercueil <paul.cercueil@analog.com>
>> + *
>> + * Licensed under the GPL-2.
>> + */
>> +
>> +#include "ad5592r-base.h"
>> +
>> +#include <linux/bitops.h>
>> +#include <linux/module.h>
>> +#include <linux/of.h>
>> +#include <linux/spi/spi.h>
>> +
>> +#define AD5592R_GPIO_READBACK_EN	BIT(10)
>> +#define AD5592R_LDAC_READBACK_EN	BIT(6)
>> +
>> +static int ad5592r_spi_wnop_r16(struct ad5592r_state *st, u16 *buf)
>> +{
>> +	struct spi_device *spi = container_of(st->dev, struct spi_device, dev);
>> +	struct spi_transfer t = {
>> +			.tx_buf	= &st->spi_msg_nop,
>> +			.rx_buf	= buf,
>> +			.len = 2
>> +		};
>> +
>> +	st->spi_msg_nop = 0; /* NOP */
>> +
>> +	return spi_sync_transfer(spi, &t, 1);
>> +}
>> +
>> +static int ad5592r_write_dac(struct ad5592r_state *st, unsigned chan, u16 value)
>> +{
>> +	struct spi_device *spi = container_of(st->dev, struct spi_device, dev);
>> +
>> +	st->spi_msg = cpu_to_be16(BIT(15) | (chan << 12) | value);
>> +
>> +	return spi_write(spi, &st->spi_msg, sizeof(st->spi_msg));
>> +}
>> +
>> +static int ad5592r_read_adc(struct ad5592r_state *st, unsigned chan, u16 *value)
>> +{
>> +	struct spi_device *spi = container_of(st->dev, struct spi_device, dev);
>> +	int ret;
>> +
>> +	st->spi_msg = cpu_to_be16((AD5592R_REG_ADC_SEQ << 11) | BIT(chan));
>> +
>> +	ret = spi_write(spi, &st->spi_msg, sizeof(st->spi_msg));
>> +	if (ret)
>> +		return ret;
>> +
>> +	/*
>> +	 * Invalid data:
>> +	 * See Figure 40. Single-Channel ADC Conversion Sequence
>> +	 */
>> +	ret = ad5592r_spi_wnop_r16(st, &st->spi_msg);
>> +	if (ret)
>> +		return ret;
>> +
>> +	ret = ad5592r_spi_wnop_r16(st, &st->spi_msg);
>> +	if (ret)
>> +		return ret;
>> +
>> +	*value = be16_to_cpu(st->spi_msg);
>> +
>> +	return 0;
>> +}
>> +
>> +static int ad5592r_reg_write(struct ad5592r_state *st, u8 reg, u16 value)
>> +{
>> +	struct spi_device *spi = container_of(st->dev, struct spi_device, dev);
>> +
>> +	st->spi_msg = cpu_to_be16((reg << 11) | value);
>> +
>> +	return spi_write(spi, &st->spi_msg, sizeof(st->spi_msg));
>> +}
>> +
>> +static int ad5592r_reg_read(struct ad5592r_state *st, u8 reg, u16 *value)
>> +{
>> +	struct spi_device *spi = container_of(st->dev, struct spi_device, dev);
>> +	int ret;
>> +
>> +	st->spi_msg = cpu_to_be16((AD5592R_REG_LDAC << 11) |
>> +				   AD5592R_LDAC_READBACK_EN | (reg << 2));
>> +
>> +	ret = spi_write(spi, &st->spi_msg, sizeof(st->spi_msg));
>> +	if (ret)
>> +		return ret;
>> +
>> +	ret = ad5592r_spi_wnop_r16(st, &st->spi_msg);
>> +	if (ret)
>> +		return ret;
>> +
>> +	*value = be16_to_cpu(st->spi_msg);
>> +
>> +	return 0;
>> +}
>> +
>> +static int ad5593r_gpio_read(struct ad5592r_state *st, u8 *value)
>> +{
>> +	int ret;
>> +
>> +	ret = ad5592r_reg_write(st, AD5592R_REG_GPIO_IN_EN,
>> +				AD5592R_GPIO_READBACK_EN | st->gpio_in);
>> +	if (ret)
>> +		return ret;
>> +
>> +	ret = ad5592r_spi_wnop_r16(st, &st->spi_msg);
>> +	if (ret)
>> +		return ret;
>> +
>> +	*value = (u8) be16_to_cpu(st->spi_msg);
>> +
>> +	return 0;
>> +}
>> +
>> +static const struct ad5592r_rw_ops ad5592r_rw_ops = {
>> +	.write_dac = ad5592r_write_dac,
>> +	.read_adc = ad5592r_read_adc,
>> +	.reg_write = ad5592r_reg_write,
>> +	.reg_read = ad5592r_reg_read,
>> +	.gpio_read = ad5593r_gpio_read,
>> +};
>> +
>> +static int ad5592r_spi_probe(struct spi_device *spi)
>> +{
>> +	const struct spi_device_id *id = spi_get_device_id(spi);
>> +
>> +	return ad5592r_probe(&spi->dev, id->name, &ad5592r_rw_ops);
>> +}
>> +
>> +static int ad5592r_spi_remove(struct spi_device *spi)
>> +{
>> +	return ad5592r_remove(&spi->dev);
>> +}
>> +
>> +static const struct spi_device_id ad5592r_spi_ids[] = {
>> +	{ .name = "ad5592r", },
>> +	{}
>> +};
>> +MODULE_DEVICE_TABLE(spi, ad5592r_spi_ids);
>> +
>> +static const struct of_device_id ad5592r_of_match[] = {
>> +	{ .compatible = "adi,ad5592r", },
>> +	{},
>> +};
>> +MODULE_DEVICE_TABLE(of, ad5592r_of_match);
>> +
>> +static struct spi_driver ad5592r_spi_driver = {
>> +	.driver = {
>> +		.name = "ad5592r",
>> +		.of_match_table = of_match_ptr(ad5592r_of_match),
>> +	},
>> +	.probe = ad5592r_spi_probe,
>> +	.remove = ad5592r_spi_remove,
>> +	.id_table = ad5592r_spi_ids,
>> +};
>> +module_spi_driver(ad5592r_spi_driver);
>> +
>> +MODULE_AUTHOR("Paul Cercueil <paul.cercueil@analog.com>");
>> +MODULE_DESCRIPTION("Analog Devices AD5592R multi-channel converters");
>> +MODULE_LICENSE("GPL v2");
>> diff --git a/drivers/iio/dac/ad5593r.c b/drivers/iio/dac/ad5593r.c
>> new file mode 100644
>> index 0000000..dca158a
>> --- /dev/null
>> +++ b/drivers/iio/dac/ad5593r.c
>> @@ -0,0 +1,131 @@
>> +/*
>> + * AD5593R Digital <-> Analog converters driver
>> + *
>> + * Copyright 2015-2016 Analog Devices Inc.
>> + * Author: Paul Cercueil <paul.cercueil@analog.com>
>> + *
>> + * Licensed under the GPL-2.
>> + */
>> +
>> +#include "ad5592r-base.h"
>> +
>> +#include <linux/bitops.h>
>> +#include <linux/i2c.h>
>> +#include <linux/module.h>
>> +#include <linux/of.h>
>> +
>> +#define AD5593R_MODE_CONF		(0 << 4)
>> +#define AD5593R_MODE_DAC_WRITE		(1 << 4)
>> +#define AD5593R_MODE_ADC_READBACK	(4 << 4)
>> +#define AD5593R_MODE_DAC_READBACK	(5 << 4)
>> +#define AD5593R_MODE_GPIO_READBACK	(6 << 4)
>> +#define AD5593R_MODE_REG_READBACK	(7 << 4)
>> +
>> +static int ad5593r_write_dac(struct ad5592r_state *st, unsigned chan, u16 value)
>> +{
>> +	struct i2c_client *i2c = to_i2c_client(st->dev);
>> +
>> +	return i2c_smbus_write_word_swapped(i2c,
>> +			AD5593R_MODE_DAC_WRITE | chan, value);
>> +}
>> +
>> +static int ad5593r_read_adc(struct ad5592r_state *st, unsigned chan, u16 *value)
>> +{
>> +	struct i2c_client *i2c = to_i2c_client(st->dev);
>> +	s32 val;
>> +
>> +	val = i2c_smbus_write_word_swapped(i2c,
>> +			AD5593R_MODE_CONF | AD5592R_REG_ADC_SEQ, BIT(chan));
>> +	if (val < 0)
>> +		return (int) val;
>> +
>> +	val = i2c_smbus_read_word_swapped(i2c, AD5593R_MODE_ADC_READBACK);
>> +	if (val < 0)
>> +		return (int) val;
>> +
>> +	*value = (u16) val;
>> +
>> +	return 0;
>> +}
>> +
>> +static int ad5593r_reg_write(struct ad5592r_state *st, u8 reg, u16 value)
>> +{
>> +	struct i2c_client *i2c = to_i2c_client(st->dev);
>> +
>> +	return i2c_smbus_write_word_swapped(i2c,
>> +			AD5593R_MODE_CONF | reg, value);
>> +}
>> +
>> +static int ad5593r_reg_read(struct ad5592r_state *st, u8 reg, u16 *value)
>> +{
>> +	struct i2c_client *i2c = to_i2c_client(st->dev);
>> +	s32 val;
>> +
>> +	val = i2c_smbus_read_word_swapped(i2c, AD5593R_MODE_REG_READBACK | reg);
>> +	if (val < 0)
>> +		return (int) val;
>> +
>> +	*value = (u16) val;
>> +
>> +	return 0;
>> +}
>> +
>> +static int ad5593r_gpio_read(struct ad5592r_state *st, u8 *value)
>> +{
>> +	struct i2c_client *i2c = to_i2c_client(st->dev);
>> +	s32 val;
>> +
>> +	val = i2c_smbus_read_word_swapped(i2c, AD5593R_MODE_GPIO_READBACK);
>> +	if (val < 0)
>> +		return (int) val;
>> +
>> +	*value = (u8) val;
>> +
>> +	return 0;
>> +}
>> +
>> +static const struct ad5592r_rw_ops ad5593r_rw_ops = {
>> +	.write_dac = ad5593r_write_dac,
>> +	.read_adc = ad5593r_read_adc,
>> +	.reg_write = ad5593r_reg_write,
>> +	.reg_read = ad5593r_reg_read,
>> +	.gpio_read = ad5593r_gpio_read,
>> +};
>> +
>> +static int ad5593r_i2c_probe(struct i2c_client *i2c,
>> +		const struct i2c_device_id *id)
>> +{
>> +	return ad5592r_probe(&i2c->dev, id->name, &ad5593r_rw_ops);
>> +}
>> +
>> +static int ad5593r_i2c_remove(struct i2c_client *i2c)
>> +{
>> +	return ad5592r_remove(&i2c->dev);
>> +}
>> +
>> +static const struct i2c_device_id ad5593r_i2c_ids[] = {
>> +	{ .name = "ad5593r", },
>> +	{},
>> +};
>> +MODULE_DEVICE_TABLE(i2c, ad5593r_i2c_ids);
>> +
>> +static const struct of_device_id ad5593r_of_match[] = {
>> +	{ .compatible = "adi,ad5593r", },
>> +	{},
>> +};
>> +MODULE_DEVICE_TABLE(of, ad5593r_of_match);
>> +
>> +static struct i2c_driver ad5593r_driver = {
>> +	.driver = {
>> +		.name = "ad5593r",
>> +		.of_match_table = of_match_ptr(ad5593r_of_match),
>> +	},
>> +	.probe = ad5593r_i2c_probe,
>> +	.remove = ad5593r_i2c_remove,
>> +	.id_table = ad5593r_i2c_ids,
>> +};
>> +module_i2c_driver(ad5593r_driver);
>> +
>> +MODULE_AUTHOR("Paul Cercueil <paul.cercueil@analog.com>");
>> +MODULE_DESCRIPTION("Analog Devices AD5592R multi-channel converters");
>> +MODULE_LICENSE("GPL v2");
>> diff --git a/include/dt-bindings/iio/adi,ad5592r.h b/include/dt-bindings/iio/adi,ad5592r.h
>> new file mode 100644
>> index 0000000..6bd519b
>> --- /dev/null
>> +++ b/include/dt-bindings/iio/adi,ad5592r.h
>> @@ -0,0 +1,16 @@
>> +
>> +#ifndef _DT_BINDINGS_ADI_AD5592R_H
>> +#define _DT_BINDINGS_ADI_AD5592R_H
>> +
>> +
>> +#define CH_MODE_ADC			1
>> +#define CH_MODE_DAC			2
>> +#define CH_MODE_DAC_AND_ADC		3
>> +#define CH_MODE_UNUSED_PULL_DOWN	4
>> +#define CH_MODE_UNUSED_OUT_LOW		5
>> +#define CH_MODE_UNUSED_OUT_HIGH		6
>> +#define CH_MODE_UNUSED_OUT_TRISTATE	7
>> +#define CH_MODE_GPIO			8
>> +#define CH_MODE_GPIO_OPEN_DRAIN		9
>> +
>> +#endif /* _DT_BINDINGS_ADI_AD5592R_H */
>>
>


-- 
Greetings,
Michael

--
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