[PATCH 3/3] iio:dac:ad5686: Add AD5671R/75R/94/94R/95R/96/96R support

From: Stefan Popa
Date: Fri Mar 30 2018 - 09:58:05 EST


The AD5694/AD5694R/AD5695R/AD5696/AD5696R are a family of 4 channel DAC
s with 12-bit, 14-bit and 16-bit precision respectively. The devices have
either no built-in reference, or built-in 2.5V reference.

The AD5671R/AD5675R are similar, except that they have 8 instead of 4
channels.

These devices are similar to AD5672R/AD5676/AD5676R and
AD5684/AD5684R/AD5684/AD5685R/AD5686/AD5686R, except that they use i2c
instead of spi. In order to add support in the previously existing driver,
three modules were created. One baseline module that has all the
chip-logic and then one module for SPI and one for I2C.

Datasheets:
http://www.analog.com/media/en/technical-documentation/data-sheets/AD5671R_5675R.pdf
http://www.analog.com/media/en/technical-documentation/data-sheets/AD5696R_5695R_5694R.pdf

Signed-off-by: Stefan Popa <stefan.popa@xxxxxxxxxx>
---
MAINTAINERS | 8 ++
drivers/iio/dac/Kconfig | 27 ++++--
drivers/iio/dac/ad5686-spi.c | 93 ++++++++++++++++++
drivers/iio/dac/ad5686.c | 222 +++++++++++++------------------------------
drivers/iio/dac/ad5686.h | 114 ++++++++++++++++++++++
drivers/iio/dac/ad5696-i2c.c | 98 +++++++++++++++++++
6 files changed, 400 insertions(+), 162 deletions(-)
create mode 100644 drivers/iio/dac/ad5686-spi.c
create mode 100644 drivers/iio/dac/ad5686.h
create mode 100644 drivers/iio/dac/ad5696-i2c.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 473ac00..002cb01 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -791,6 +791,14 @@ M: Michael Hanselmann <linux-kernel@xxxxxxxxx>
S: Supported
F: drivers/macintosh/ams/

+ANALOG DEVICES INC AD5686 DRIVER
+M: Stefan Popa <stefan.popa@xxxxxxxxxx>
+L: linux-pm@xxxxxxxxxxxxxxx
+W: http://ez.analog.com/community/linux-device-drivers
+S: Supported
+F: drivers/iio/dac/ad5686*
+F: drivers/iio/dac/ad5696*
+
ANALOG DEVICES INC AD9389B DRIVER
M: Hans Verkuil <hans.verkuil@xxxxxxxxx>
L: linux-media@xxxxxxxxxxxxxxx
diff --git a/drivers/iio/dac/Kconfig b/drivers/iio/dac/Kconfig
index 965d5c0..dab0b8a 100644
--- a/drivers/iio/dac/Kconfig
+++ b/drivers/iio/dac/Kconfig
@@ -131,15 +131,30 @@ config LTC2632
module will be called ltc2632.

config AD5686
- tristate "Analog Devices AD5686R/AD5685R/AD5684R DAC SPI driver"
+ tristate
+
+config AD5686_SPI
+ tristate "Analog Devices AD5686 and similar multi-channel DACs (SPI)"
depends on SPI
+ select AD5686
help
- Say yes here to build support for Analog Devices AD5686R, AD5685R,
- AD5684R, AD5791 Voltage Output Digital to
- Analog Converter.
+ Say yes here to build support for Analog Devices AD5672R, AD5676,
+ AD5676R, AD5684, AD5684R, AD5684R, AD5685R, AD5686, AD5686R.
+ Voltage Output Digital to Analog Converter.

- To compile this driver as a module, choose M here: the
- module will be called ad5686.
+ To compile this driver as a module, choose M here: the
+ module will be called ad5686.
+
+config AD5696_I2C
+ tristate "Analog Devices AD5696 and similar multi-channel DACs (I2C)"
+ depends on I2C
+ select AD5686
+ help
+ Say yes here to build support for Analog Devices AD5671R, AD5675R,
+ AD5694, AD5694R, AD5695R, AD5696, AD5696R Voltage Output Digital to
+ Analog Converter.
+ To compile this driver as a module, choose M here: the module will be
+ called ad5696.

config AD5755
tristate "Analog Devices AD5755/AD5755-1/AD5757/AD5735/AD5737 DAC driver"
diff --git a/drivers/iio/dac/ad5686-spi.c b/drivers/iio/dac/ad5686-spi.c
new file mode 100644
index 0000000..d68579b
--- /dev/null
+++ b/drivers/iio/dac/ad5686-spi.c
@@ -0,0 +1,93 @@
+/*
+ * AD5672R, AD5676, AD5676R, AD5684, AD5684R, AD5684R, AD5685R, AD5686, AD5686R
+ * Digital to analog converters driver
+ *
+ * Copyright 2018 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include "ad5686.h"
+
+#include <linux/module.h>
+#include <linux/spi/spi.h>
+
+static int ad5686_spi_write(struct ad5686_state *st,
+ u8 cmd, u8 addr, u16 val)
+{
+ struct spi_device *spi = to_spi_device(st->dev);
+
+ st->data[0].d32 = cpu_to_be32(AD5686_CMD(cmd) |
+ AD5686_ADDR(addr) |
+ val);
+
+ return spi_write(spi, &st->data[0].d8[1], 3);
+}
+
+static int ad5686_spi_read(struct ad5686_state *st, u8 addr)
+{
+ struct spi_transfer t[] = {
+ {
+ .tx_buf = &st->data[0].d8[1],
+ .len = 3,
+ .cs_change = 1,
+ }, {
+ .tx_buf = &st->data[1].d8[1],
+ .rx_buf = &st->data[2].d8[1],
+ .len = 3,
+ },
+ };
+ struct spi_device *spi = to_spi_device(st->dev);
+ int ret;
+
+ st->data[0].d32 = cpu_to_be32(AD5686_CMD(AD5686_CMD_READBACK_ENABLE) |
+ AD5686_ADDR(addr));
+ st->data[1].d32 = cpu_to_be32(AD5686_CMD(AD5686_CMD_NOOP));
+
+ ret = spi_sync_transfer(spi, t, ARRAY_SIZE(t));
+ if (ret < 0)
+ return ret;
+
+ return be32_to_cpu(st->data[2].d32);
+}
+
+static int ad5686_spi_probe(struct spi_device *spi)
+{
+ const struct spi_device_id *id = spi_get_device_id(spi);
+
+ return ad5686_probe(&spi->dev, id->driver_data, id->name,
+ ad5686_spi_write, ad5686_spi_read);
+}
+
+static int ad5686_spi_remove(struct spi_device *spi)
+{
+ return ad5686_remove(&spi->dev);
+}
+
+static const struct spi_device_id ad5686_spi_id[] = {
+ {"ad5672r", ID_AD5672R},
+ {"ad5676", ID_AD5676},
+ {"ad5676r", ID_AD5676R},
+ {"ad5684", ID_AD5684},
+ {"ad5684r", ID_AD5684R},
+ {"ad5685r", ID_AD5685R},
+ {"ad5686", ID_AD5686},
+ {"ad5686r", ID_AD5686R},
+ {}
+};
+MODULE_DEVICE_TABLE(spi, ad5686_spi_id);
+
+static struct spi_driver ad5686_spi_driver = {
+ .driver = {
+ .name = "ad5686",
+ },
+ .probe = ad5686_spi_probe,
+ .remove = ad5686_spi_remove,
+ .id_table = ad5686_spi_id,
+};
+
+module_spi_driver(ad5686_spi_driver);
+
+MODULE_AUTHOR("Stefan Popa <stefan.popa@xxxxxxxxxx>");
+MODULE_DESCRIPTION("Analog Devices AD5686 and similar multi-channel DACs");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/iio/dac/ad5686.c b/drivers/iio/dac/ad5686.c
index 5fb0179..e4ea0dc 100644
--- a/drivers/iio/dac/ad5686.c
+++ b/drivers/iio/dac/ad5686.c
@@ -11,7 +11,6 @@
#include <linux/device.h>
#include <linux/module.h>
#include <linux/kernel.h>
-#include <linux/spi/spi.h>
#include <linux/slab.h>
#include <linux/sysfs.h>
#include <linux/regulator/consumer.h>
@@ -19,128 +18,28 @@
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>

-#define AD5686_ADDR(x) ((x) << 16)
-#define AD5686_CMD(x) ((x) << 20)
-
-#define AD5686_ADDR_DAC(chan) (0x1 << (chan))
-#define AD5686_ADDR_ALL_DAC 0xF
-
-#define AD5686_CMD_NOOP 0x0
-#define AD5686_CMD_WRITE_INPUT_N 0x1
-#define AD5686_CMD_UPDATE_DAC_N 0x2
-#define AD5686_CMD_WRITE_INPUT_N_UPDATE_N 0x3
-#define AD5686_CMD_POWERDOWN_DAC 0x4
-#define AD5686_CMD_LDAC_MASK 0x5
-#define AD5686_CMD_RESET 0x6
-#define AD5686_CMD_INTERNAL_REFER_SETUP 0x7
-#define AD5686_CMD_DAISY_CHAIN_ENABLE 0x8
-#define AD5686_CMD_READBACK_ENABLE 0x9
-
-#define AD5686_LDAC_PWRDN_NONE 0x0
-#define AD5686_LDAC_PWRDN_1K 0x1
-#define AD5686_LDAC_PWRDN_100K 0x2
-#define AD5686_LDAC_PWRDN_3STATE 0x3
-
-/**
- * struct ad5686_chip_info - chip specific information
- * @int_vref_mv: AD5620/40/60: the internal reference voltage
- * @num_channels: number of channels
- * @channel: channel specification
-*/
-
-struct ad5686_chip_info {
- u16 int_vref_mv;
- unsigned int num_channels;
- struct iio_chan_spec *channels;
-};
-
-/**
- * struct ad5446_state - driver instance specific data
- * @spi: spi_device
- * @chip_info: chip model specific constants, available modes etc
- * @reg: supply regulator
- * @vref_mv: actual reference voltage used
- * @pwr_down_mask: power down mask
- * @pwr_down_mode: current power down mode
- * @data: spi transfer buffers
- */
+#include "ad5686.h"

-struct ad5686_state {
- struct spi_device *spi;
- const struct ad5686_chip_info *chip_info;
- struct regulator *reg;
- unsigned short vref_mv;
- unsigned pwr_down_mask;
- unsigned pwr_down_mode;
- /*
- * DMA (thus cache coherency maintenance) requires the
- * transfer buffers to live in their own cache lines.
- */
-
- union {
- __be32 d32;
- u8 d8[4];
- } data[3] ____cacheline_aligned;
+static const char * const ad5686_powerdown_modes[] = {
+ "1kohm_to_gnd",
+ "100kohm_to_gnd",
+ "three_state"
};

-/**
- * ad5686_supported_device_ids:
- */
-
-enum ad5686_supported_device_ids {
- ID_AD5672R,
- ID_AD5676,
- ID_AD5676R,
- ID_AD5684,
- ID_AD5684R,
- ID_AD5685R,
- ID_AD5686,
- ID_AD5686R
-};
-static int ad5686_spi_write(struct ad5686_state *st,
- u8 cmd, u8 addr, u16 val, u8 shift)
+static int ad5686_write(struct ad5686_state *st,
+ u8 cmd, u8 addr, u16 val, u8 shift)
{
val <<= shift;

- st->data[0].d32 = cpu_to_be32(AD5686_CMD(cmd) |
- AD5686_ADDR(addr) |
- val);
-
- return spi_write(st->spi, &st->data[0].d8[1], 3);
+ return st->write(st, cmd, addr, val);
}

-static int ad5686_spi_read(struct ad5686_state *st, u8 addr)
+static int ad5686_read(struct ad5686_state *st, u8 addr)
{
- struct spi_transfer t[] = {
- {
- .tx_buf = &st->data[0].d8[1],
- .len = 3,
- .cs_change = 1,
- }, {
- .tx_buf = &st->data[1].d8[1],
- .rx_buf = &st->data[2].d8[1],
- .len = 3,
- },
- };
- int ret;

- st->data[0].d32 = cpu_to_be32(AD5686_CMD(AD5686_CMD_READBACK_ENABLE) |
- AD5686_ADDR(addr));
- st->data[1].d32 = cpu_to_be32(AD5686_CMD(AD5686_CMD_NOOP));
-
- ret = spi_sync_transfer(st->spi, t, ARRAY_SIZE(t));
- if (ret < 0)
- return ret;
-
- return be32_to_cpu(st->data[2].d32);
+ return st->read(st, addr);
}

-static const char * const ad5686_powerdown_modes[] = {
- "1kohm_to_gnd",
- "100kohm_to_gnd",
- "three_state"
-};
-
static int ad5686_get_powerdown_mode(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan)
{
@@ -196,8 +95,8 @@ static ssize_t ad5686_write_dac_powerdown(struct iio_dev *indio_dev,
else
st->pwr_down_mask &= ~(0x3 << (chan->channel * 2));

- ret = ad5686_spi_write(st, AD5686_CMD_POWERDOWN_DAC, 0,
- st->pwr_down_mask & st->pwr_down_mode, 0);
+ ret = ad5686_write(st, AD5686_CMD_POWERDOWN_DAC, 0,
+ st->pwr_down_mask & st->pwr_down_mode, 0);

return ret ? ret : len;
}
@@ -214,7 +113,7 @@ static int ad5686_read_raw(struct iio_dev *indio_dev,
switch (m) {
case IIO_CHAN_INFO_RAW:
mutex_lock(&indio_dev->mlock);
- ret = ad5686_spi_read(st, chan->address);
+ ret = ad5686_read(st, chan->address);
mutex_unlock(&indio_dev->mlock);
if (ret < 0)
return ret;
@@ -243,11 +142,11 @@ static int ad5686_write_raw(struct iio_dev *indio_dev,
return -EINVAL;

mutex_lock(&indio_dev->mlock);
- ret = ad5686_spi_write(st,
- AD5686_CMD_WRITE_INPUT_N_UPDATE_N,
- chan->address,
- val,
- chan->scan_type.shift);
+ ret = ad5686_write(st,
+ AD5686_CMD_WRITE_INPUT_N_UPDATE_N,
+ chan->address,
+ val,
+ chan->scan_type.shift);
mutex_unlock(&indio_dev->mlock);
break;
default:
@@ -318,11 +217,21 @@ DECLARE_AD5686_CHANNELS(ad5685r_channels, 14, 2);
DECLARE_AD5686_CHANNELS(ad5686_channels, 16, 0);

static const struct ad5686_chip_info ad5686_chip_info_tbl[] = {
+ [ID_AD5671R] = {
+ .channels = ad5672_channels,
+ .int_vref_mv = 2500,
+ .num_channels = 8,
+ },
[ID_AD5672R] = {
.channels = ad5672_channels,
.int_vref_mv = 2500,
.num_channels = 8,
},
+ [ID_AD5675R] = {
+ .channels = ad5676_channels,
+ .int_vref_mv = 2500,
+ .num_channels = 8,
+ },
[ID_AD5676] = {
.channels = ad5676_channels,
.num_channels = 8,
@@ -355,22 +264,47 @@ static const struct ad5686_chip_info ad5686_chip_info_tbl[] = {
.int_vref_mv = 2500,
.num_channels = 4,
},
+ [ID_AD5694] = {
+ .channels = ad5684_channels,
+ .num_channels = 4,
+ },
+ [ID_AD5694R] = {
+ .channels = ad5684_channels,
+ .int_vref_mv = 2500,
+ .num_channels = 4,
+ },
+ [ID_AD5696] = {
+ .channels = ad5686_channels,
+ .num_channels = 4,
+ },
+ [ID_AD5696R] = {
+ .channels = ad5686_channels,
+ .int_vref_mv = 2500,
+ .num_channels = 4,
+ },
};

-static int ad5686_probe(struct spi_device *spi)
+int ad5686_probe(struct device *dev,
+ enum ad5686_supported_device_ids chip_type,
+ const char *name, ad5686_write_func write,
+ ad5686_read_func read)
{
struct ad5686_state *st;
struct iio_dev *indio_dev;
int ret, voltage_uv = 0;

- indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
+ indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
if (indio_dev == NULL)
return -ENOMEM;

st = iio_priv(indio_dev);
- spi_set_drvdata(spi, indio_dev);
+ dev_set_drvdata(dev, indio_dev);
+
+ st->dev = dev;
+ st->write = write;
+ st->read = read;

- st->reg = devm_regulator_get_optional(&spi->dev, "vcc");
+ st->reg = devm_regulator_get_optional(dev, "vcc");
if (!IS_ERR(st->reg)) {
ret = regulator_enable(st->reg);
if (ret)
@@ -383,28 +317,25 @@ static int ad5686_probe(struct spi_device *spi)
voltage_uv = ret;
}

- st->chip_info =
- &ad5686_chip_info_tbl[spi_get_device_id(spi)->driver_data];
+ st->chip_info = &ad5686_chip_info_tbl[chip_type];

if (voltage_uv)
st->vref_mv = voltage_uv / 1000;
else
st->vref_mv = st->chip_info->int_vref_mv;

- st->spi = spi;
-
/* Set all the power down mode for all channels to 1K pulldown */
st->pwr_down_mode = 0x55;

- indio_dev->dev.parent = &spi->dev;
- indio_dev->name = spi_get_device_id(spi)->name;
+ indio_dev->dev.parent = dev;
+ indio_dev->name = name;
indio_dev->info = &ad5686_info;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->channels = st->chip_info->channels;
indio_dev->num_channels = st->chip_info->num_channels;

- ret = ad5686_spi_write(st, AD5686_CMD_INTERNAL_REFER_SETUP, 0,
- !!voltage_uv, 0);
+ ret = ad5686_write(st, AD5686_CMD_INTERNAL_REFER_SETUP,
+ 0, !!voltage_uv, 0);
if (ret)
goto error_disable_reg;

@@ -419,10 +350,11 @@ static int ad5686_probe(struct spi_device *spi)
regulator_disable(st->reg);
return ret;
}
+EXPORT_SYMBOL_GPL(ad5686_probe);

-static int ad5686_remove(struct spi_device *spi)
+int ad5686_remove(struct device *dev)
{
- struct iio_dev *indio_dev = spi_get_drvdata(spi);
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct ad5686_state *st = iio_priv(indio_dev);

iio_device_unregister(indio_dev);
@@ -431,29 +363,7 @@ static int ad5686_remove(struct spi_device *spi)

return 0;
}
-
-static const struct spi_device_id ad5686_id[] = {
- {"ad5672r", ID_AD5672R},
- {"ad5676", ID_AD5676},
- {"ad5676r", ID_AD5676R},
- {"ad5684", ID_AD5684},
- {"ad5684r", ID_AD5684R},
- {"ad5685r", ID_AD5685R},
- {"ad5686", ID_AD5686},
- {"ad5686r", ID_AD5686R},
- {}
-};
-MODULE_DEVICE_TABLE(spi, ad5686_id);
-
-static struct spi_driver ad5686_driver = {
- .driver = {
- .name = "ad5686",
- },
- .probe = ad5686_probe,
- .remove = ad5686_remove,
- .id_table = ad5686_id,
-};
-module_spi_driver(ad5686_driver);
+EXPORT_SYMBOL_GPL(ad5686_remove);

MODULE_AUTHOR("Michael Hennerich <hennerich@xxxxxxxxxxxxxxxxxxxx>");
MODULE_DESCRIPTION("Analog Devices AD5686/85/84 DAC");
diff --git a/drivers/iio/dac/ad5686.h b/drivers/iio/dac/ad5686.h
new file mode 100644
index 0000000..b2b0110
--- /dev/null
+++ b/drivers/iio/dac/ad5686.h
@@ -0,0 +1,114 @@
+#ifndef __DRIVERS_IIO_DAC_AD5686_H__
+#define __DRIVERS_IIO_DAC_AD5686_H__
+
+#include <linux/types.h>
+#include <linux/cache.h>
+#include <linux/mutex.h>
+#include <linux/kernel.h>
+
+#define AD5686_ADDR(x) ((x) << 16)
+#define AD5686_CMD(x) ((x) << 20)
+
+#define AD5686_ADDR_DAC(chan) (0x1 << (chan))
+#define AD5686_ADDR_ALL_DAC 0xF
+
+#define AD5686_CMD_NOOP 0x0
+#define AD5686_CMD_WRITE_INPUT_N 0x1
+#define AD5686_CMD_UPDATE_DAC_N 0x2
+#define AD5686_CMD_WRITE_INPUT_N_UPDATE_N 0x3
+#define AD5686_CMD_POWERDOWN_DAC 0x4
+#define AD5686_CMD_LDAC_MASK 0x5
+#define AD5686_CMD_RESET 0x6
+#define AD5686_CMD_INTERNAL_REFER_SETUP 0x7
+#define AD5686_CMD_DAISY_CHAIN_ENABLE 0x8
+#define AD5686_CMD_READBACK_ENABLE 0x9
+
+#define AD5686_LDAC_PWRDN_NONE 0x0
+#define AD5686_LDAC_PWRDN_1K 0x1
+#define AD5686_LDAC_PWRDN_100K 0x2
+#define AD5686_LDAC_PWRDN_3STATE 0x3
+
+/**
+ * ad5686_supported_device_ids:
+ */
+enum ad5686_supported_device_ids {
+ ID_AD5671R,
+ ID_AD5672R,
+ ID_AD5675R,
+ ID_AD5676,
+ ID_AD5676R,
+ ID_AD5684,
+ ID_AD5684R,
+ ID_AD5685R,
+ ID_AD5686,
+ ID_AD5686R,
+ ID_AD5694,
+ ID_AD5694R,
+ ID_AD5695R,
+ ID_AD5696,
+ ID_AD5696R,
+};
+
+struct ad5686_state;
+
+typedef int (*ad5686_write_func)(struct ad5686_state *st,
+ u8 cmd, u8 addr, u16 val);
+
+typedef int (*ad5686_read_func)(struct ad5686_state *st, u8 addr);
+
+/**
+ * struct ad5686_chip_info - chip specific information
+ * @int_vref_mv: AD5620/40/60: the internal reference voltage
+ * @num_channels: number of channels
+ * @channel: channel specification
+ */
+
+struct ad5686_chip_info {
+ u16 int_vref_mv;
+ unsigned int num_channels;
+ struct iio_chan_spec *channels;
+};
+
+/**
+ * struct ad5446_state - driver instance specific data
+ * @spi: spi_device
+ * @chip_info: chip model specific constants, available modes etc
+ * @reg: supply regulator
+ * @vref_mv: actual reference voltage used
+ * @pwr_down_mask: power down mask
+ * @pwr_down_mode: current power down mode
+ * @data: spi transfer buffers
+ */
+
+struct ad5686_state {
+ struct device *dev;
+ const struct ad5686_chip_info *chip_info;
+ struct regulator *reg;
+ unsigned short vref_mv;
+ unsigned int pwr_down_mask;
+ unsigned int pwr_down_mode;
+ ad5686_write_func write;
+ ad5686_read_func read;
+
+ /*
+ * DMA (thus cache coherency maintenance) requires the
+ * transfer buffers to live in their own cache lines.
+ */
+
+ union {
+ __be32 d32;
+ __be16 d16;
+ u8 d8[4];
+ } data[3] ____cacheline_aligned;
+};
+
+
+int ad5686_probe(struct device *dev,
+ enum ad5686_supported_device_ids chip_type,
+ const char *name, ad5686_write_func write,
+ ad5686_read_func read);
+
+int ad5686_remove(struct device *dev);
+
+
+#endif /* __DRIVERS_IIO_DAC_AD5686_H__ */
diff --git a/drivers/iio/dac/ad5696-i2c.c b/drivers/iio/dac/ad5696-i2c.c
new file mode 100644
index 0000000..c9187de
--- /dev/null
+++ b/drivers/iio/dac/ad5696-i2c.c
@@ -0,0 +1,98 @@
+/*
+ * AD5671R, AD5675R, AD5694, AD5694R, AD5695R, AD5696, AD5696R
+ * Digital to analog converters driver
+ *
+ * Copyright 2018 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include "ad5686.h"
+
+#include <linux/module.h>
+#include <linux/i2c.h>
+
+static int ad5686_i2c_read(struct ad5686_state *st, u8 addr)
+{
+ struct i2c_client *i2c = to_i2c_client(st->dev);
+ struct i2c_msg msg[2] = {
+ {
+ .addr = i2c->addr,
+ .flags = i2c->flags,
+ .len = 3,
+ .buf = &st->data[0].d8[1],
+ },
+ {
+ .addr = i2c->addr,
+ .flags = i2c->flags | I2C_M_RD,
+ .len = 2,
+ .buf = (char *)&st->data[0].d16,
+ },
+ };
+ int ret;
+
+ st->data[0].d32 = cpu_to_be32(AD5686_CMD(AD5686_CMD_NOOP) |
+ AD5686_ADDR(addr) |
+ 0x00);
+
+ ret = i2c_transfer(i2c->adapter, msg, 2);
+ if (ret < 0)
+ return ret;
+
+ return be16_to_cpu(st->data[0].d16);
+}
+
+static int ad5686_i2c_write(struct ad5686_state *st,
+ u8 cmd, u8 addr, u16 val)
+{
+ struct i2c_client *i2c = to_i2c_client(st->dev);
+ int ret;
+
+ st->data[0].d32 = cpu_to_be32(AD5686_CMD(cmd) | AD5686_ADDR(addr)
+ | val);
+
+ ret = i2c_master_send(i2c, &st->data[0].d8[1], 3);
+ if (ret < 0)
+ return ret;
+
+ return (ret != 3) ? -EIO : 0;
+}
+
+static int ad5686_i2c_probe(struct i2c_client *i2c,
+ const struct i2c_device_id *id)
+{
+ return ad5686_probe(&i2c->dev, id->driver_data, id->name,
+ ad5686_i2c_write, ad5686_i2c_read);
+}
+
+static int ad5686_i2c_remove(struct i2c_client *i2c)
+{
+ return ad5686_remove(&i2c->dev);
+}
+
+static const struct i2c_device_id ad5686_i2c_id[] = {
+ {"ad5671r", ID_AD5671R},
+ {"ad5675r", ID_AD5675R},
+ {"ad5694", ID_AD5694},
+ {"ad5694r", ID_AD5694R},
+ {"ad5695r", ID_AD5695R},
+ {"ad5696", ID_AD5696},
+ {"ad5696r", ID_AD5696R},
+ {}
+};
+MODULE_DEVICE_TABLE(i2c, i2c_device_id);
+
+static struct i2c_driver ad5686_i2c_driver = {
+ .driver = {
+ .name = "ad5696",
+ },
+ .probe = ad5686_i2c_probe,
+ .remove = ad5686_i2c_remove,
+ .id_table = ad5686_i2c_id,
+};
+
+module_i2c_driver(ad5686_i2c_driver);
+
+MODULE_AUTHOR("Stefan Popa <stefan.popa@xxxxxxxxxx>");
+MODULE_DESCRIPTION("Analog Devices AD5686 and similar multi-channel DACs");
+MODULE_LICENSE("GPL v2");
--
2.7.4