iio: dac: ad5770r: Add AD5770R support
authorAlexandru Tachici <alexandru.tachici@analog.com>
Tue, 18 Feb 2020 12:10:30 +0000 (14:10 +0200)
committerJonathan Cameron <Jonathan.Cameron@huawei.com>
Sun, 8 Mar 2020 17:28:41 +0000 (17:28 +0000)
The AD5770R is a 6-channel, 14-bit resolution, low noise, programmable
current output digital-to-analog converter (DAC) for photonics control
applications.

It contains five 14-bit resolution current sourcing DAC channels and one
14-bit resolution current sourcing/sinking DAC channel.

Signed-off-by: Mircea Caprioru <mircea.caprioru@analog.com>
Signed-off-by: Alexandru Tachici <alexandru.tachici@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
drivers/iio/dac/Kconfig
drivers/iio/dac/Makefile
drivers/iio/dac/ad5770r.c [new file with mode: 0644]

index 3adbd2de38a1a4b480c45bd400cd561addfae131..63916a6142eca903a6ea39182c78f7e9e9f2b0b5 100644 (file)
@@ -209,6 +209,16 @@ config AD5764
          To compile this driver as a module, choose M here: the
          module will be called ad5764.
 
+config AD5770R
+       tristate "Analog Devices AD5770R IDAC driver"
+       depends on SPI_MASTER
+       help
+         Say yes here to build support for Analog Devices AD5770R Digital to
+         Analog Converter.
+
+         To compile this driver as a module, choose M here: the
+         module will be called ad5770r.
+
 config AD5791
        tristate "Analog Devices AD5760/AD5780/AD5781/AD5790/AD5791 DAC SPI driver"
        depends on SPI
index 1369fa1d2f0ee571d24e448d975f2191d26afec1..2fc48116772406b4e41d232479574a03f4969b1a 100644 (file)
@@ -19,6 +19,7 @@ obj-$(CONFIG_AD5755) += ad5755.o
 obj-$(CONFIG_AD5755) += ad5758.o
 obj-$(CONFIG_AD5761) += ad5761.o
 obj-$(CONFIG_AD5764) += ad5764.o
+obj-$(CONFIG_AD5770R) += ad5770r.o
 obj-$(CONFIG_AD5791) += ad5791.o
 obj-$(CONFIG_AD5686) += ad5686.o
 obj-$(CONFIG_AD5686_SPI) += ad5686-spi.o
diff --git a/drivers/iio/dac/ad5770r.c b/drivers/iio/dac/ad5770r.c
new file mode 100644 (file)
index 0000000..a98ea76
--- /dev/null
@@ -0,0 +1,695 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * AD5770R Digital to analog converters driver
+ *
+ * Copyright 2018 Analog Devices Inc.
+ */
+
+#include <linux/bits.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/gpio/consumer.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/property.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+#include <linux/spi/spi.h>
+
+#define ADI_SPI_IF_CONFIG_A            0x00
+#define ADI_SPI_IF_CONFIG_B            0x01
+#define ADI_SPI_IF_DEVICE_CONFIG       0x02
+#define ADI_SPI_IF_CHIP_TYPE           0x03
+#define ADI_SPI_IF_PRODUCT_ID_L                0x04
+#define ADI_SPI_IF_PRODUCT_ID_H                0x05
+#define ADI_SPI_IF_CHIP_GRADE          0x06
+#define ADI_SPI_IF_SCRACTH_PAD         0x0A
+#define ADI_SPI_IF_SPI_REVISION                0x0B
+#define ADI_SPI_IF_SPI_VENDOR_L                0x0C
+#define ADI_SPI_IF_SPI_VENDOR_H                0x0D
+#define ADI_SPI_IF_SPI_STREAM_MODE     0x0E
+#define ADI_SPI_IF_CONFIG_C            0x10
+#define ADI_SPI_IF_STATUS_A            0x11
+
+/* ADI_SPI_IF_CONFIG_A */
+#define ADI_SPI_IF_SW_RESET_MSK                (BIT(0) | BIT(7))
+#define ADI_SPI_IF_SW_RESET_SEL(x)     ((x) & ADI_SPI_IF_SW_RESET_MSK)
+#define ADI_SPI_IF_ADDR_ASC_MSK                (BIT(2) | BIT(5))
+#define ADI_SPI_IF_ADDR_ASC_SEL(x)     (((x) << 2) & ADI_SPI_IF_ADDR_ASC_MSK)
+
+/* ADI_SPI_IF_CONFIG_B */
+#define ADI_SPI_IF_SINGLE_INS_MSK      BIT(7)
+#define ADI_SPI_IF_SINGLE_INS_SEL(x)   FIELD_PREP(ADI_SPI_IF_SINGLE_INS_MSK, x)
+#define ADI_SPI_IF_SHORT_INS_MSK       BIT(7)
+#define ADI_SPI_IF_SHORT_INS_SEL(x)    FIELD_PREP(ADI_SPI_IF_SINGLE_INS_MSK, x)
+
+/* ADI_SPI_IF_CONFIG_C */
+#define ADI_SPI_IF_STRICT_REG_MSK      BIT(5)
+#define ADI_SPI_IF_STRICT_REG_GET(x)   FIELD_GET(ADI_SPI_IF_STRICT_REG_MSK, x)
+
+/* AD5770R configuration registers */
+#define AD5770R_CHANNEL_CONFIG         0x14
+#define AD5770R_OUTPUT_RANGE(ch)       (0x15 + (ch))
+#define AD5770R_FILTER_RESISTOR(ch)    (0x1D + (ch))
+#define AD5770R_REFERENCE              0x1B
+#define AD5770R_DAC_LSB(ch)            (0x26 + 2 * (ch))
+#define AD5770R_DAC_MSB(ch)            (0x27 + 2 * (ch))
+#define AD5770R_CH_SELECT              0x34
+#define AD5770R_CH_ENABLE              0x44
+
+/* AD5770R_CHANNEL_CONFIG */
+#define AD5770R_CFG_CH0_SINK_EN(x)             (((x) & 0x1) << 7)
+#define AD5770R_CFG_SHUTDOWN_B(x, ch)          (((x) & 0x1) << (ch))
+
+/* AD5770R_OUTPUT_RANGE */
+#define AD5770R_RANGE_OUTPUT_SCALING(x)                (((x) & GENMASK(5, 0)) << 2)
+#define AD5770R_RANGE_MODE(x)                  ((x) & GENMASK(1, 0))
+
+/* AD5770R_REFERENCE */
+#define AD5770R_REF_RESISTOR_SEL(x)            (((x) & 0x1) << 2)
+#define AD5770R_REF_SEL(x)                     ((x) & GENMASK(1, 0))
+
+/* AD5770R_CH_ENABLE */
+#define AD5770R_CH_SET(x, ch)          (((x) & 0x1) << (ch))
+
+#define AD5770R_MAX_CHANNELS   6
+#define AD5770R_MAX_CH_MODES   14
+#define AD5770R_LOW_VREF_mV    1250
+#define AD5770R_HIGH_VREF_mV   2500
+
+enum ad5770r_ch0_modes {
+       AD5770R_CH0_0_300 = 0,
+       AD5770R_CH0_NEG_60_0,
+       AD5770R_CH0_NEG_60_300
+};
+
+enum ad5770r_ch1_modes {
+       AD5770R_CH1_0_140_LOW_HEAD = 1,
+       AD5770R_CH1_0_140_LOW_NOISE,
+       AD5770R_CH1_0_250
+};
+
+enum ad5770r_ch2_5_modes {
+       AD5770R_CH_LOW_RANGE = 0,
+       AD5770R_CH_HIGH_RANGE
+};
+
+enum ad5770r_ref_v {
+       AD5770R_EXT_2_5_V = 0,
+       AD5770R_INT_1_25_V_OUT_ON,
+       AD5770R_EXT_1_25_V,
+       AD5770R_INT_1_25_V_OUT_OFF
+};
+
+enum ad5770r_output_filter_resistor {
+       AD5770R_FILTER_60_OHM = 0x0,
+       AD5770R_FILTER_5_6_KOHM = 0x5,
+       AD5770R_FILTER_11_2_KOHM,
+       AD5770R_FILTER_22_2_KOHM,
+       AD5770R_FILTER_44_4_KOHM,
+       AD5770R_FILTER_104_KOHM,
+};
+
+struct ad5770r_out_range {
+       u8      out_scale;
+       u8      out_range_mode;
+};
+
+/**
+ * struct ad5770R_state - driver instance specific data
+ * @spi:               spi_device
+ * @regmap:            regmap
+ * @vref_reg:          fixed regulator for reference configuration
+ * @gpio_reset:                gpio descriptor
+ * @output_mode:       array contains channels output ranges
+ * @vref:              reference value
+ * @ch_pwr_down:       powerdown flags
+ * @internal_ref:      internal reference flag
+ * @external_res:      external 2.5k resistor flag
+ * @transf_buf:                cache aligned buffer for spi read/write
+ */
+struct ad5770r_state {
+       struct spi_device               *spi;
+       struct regmap                   *regmap;
+       struct regulator                *vref_reg;
+       struct gpio_desc                *gpio_reset;
+       struct ad5770r_out_range        output_mode[AD5770R_MAX_CHANNELS];
+       int                             vref;
+       bool                            ch_pwr_down[AD5770R_MAX_CHANNELS];
+       bool                            internal_ref;
+       bool                            external_res;
+       u8                              transf_buf[2] ____cacheline_aligned;
+};
+
+static const struct regmap_config ad5770r_spi_regmap_config = {
+       .reg_bits = 8,
+       .val_bits = 8,
+       .read_flag_mask = BIT(7),
+};
+
+struct ad5770r_output_modes {
+       unsigned int ch;
+       u8 mode;
+       int min;
+       int max;
+};
+
+static struct ad5770r_output_modes ad5770r_rng_tbl[] = {
+       { 0, AD5770R_CH0_0_300, 0, 300 },
+       { 0, AD5770R_CH0_NEG_60_0, -60, 0 },
+       { 0, AD5770R_CH0_NEG_60_300, -60, 300 },
+       { 1, AD5770R_CH1_0_140_LOW_HEAD, 0, 140 },
+       { 1, AD5770R_CH1_0_140_LOW_NOISE, 0, 140 },
+       { 1, AD5770R_CH1_0_250, 0, 250 },
+       { 2, AD5770R_CH_LOW_RANGE, 0, 55 },
+       { 2, AD5770R_CH_HIGH_RANGE, 0, 150 },
+       { 3, AD5770R_CH_LOW_RANGE, 0, 45 },
+       { 3, AD5770R_CH_HIGH_RANGE, 0, 100 },
+       { 4, AD5770R_CH_LOW_RANGE, 0, 45 },
+       { 4, AD5770R_CH_HIGH_RANGE, 0, 100 },
+       { 5, AD5770R_CH_LOW_RANGE, 0, 45 },
+       { 5, AD5770R_CH_HIGH_RANGE, 0, 100 },
+};
+
+static const unsigned int ad5770r_filter_freqs[] = {
+       153, 357, 715, 1400, 2800, 262000,
+};
+
+static const unsigned int ad5770r_filter_reg_vals[] = {
+       AD5770R_FILTER_104_KOHM,
+       AD5770R_FILTER_44_4_KOHM,
+       AD5770R_FILTER_22_2_KOHM,
+       AD5770R_FILTER_11_2_KOHM,
+       AD5770R_FILTER_5_6_KOHM,
+       AD5770R_FILTER_60_OHM
+};
+
+static int ad5770r_set_output_mode(struct ad5770r_state *st,
+                                  const struct ad5770r_out_range *out_mode,
+                                  int channel)
+{
+       unsigned int regval;
+
+       regval = AD5770R_RANGE_OUTPUT_SCALING(out_mode->out_scale) |
+                AD5770R_RANGE_MODE(out_mode->out_range_mode);
+
+       return regmap_write(st->regmap,
+                           AD5770R_OUTPUT_RANGE(channel), regval);
+}
+
+static int ad5770r_set_reference(struct ad5770r_state *st)
+{
+       unsigned int regval;
+
+       regval = AD5770R_REF_RESISTOR_SEL(st->external_res);
+
+       if (st->internal_ref) {
+               regval |= AD5770R_REF_SEL(AD5770R_INT_1_25_V_OUT_OFF);
+       } else {
+               switch (st->vref) {
+               case AD5770R_LOW_VREF_mV:
+                       regval |= AD5770R_REF_SEL(AD5770R_EXT_1_25_V);
+                       break;
+               case AD5770R_HIGH_VREF_mV:
+                       regval |= AD5770R_REF_SEL(AD5770R_EXT_2_5_V);
+                       break;
+               default:
+                       regval = AD5770R_REF_SEL(AD5770R_INT_1_25_V_OUT_OFF);
+                       break;
+               }
+       }
+
+       return regmap_write(st->regmap, AD5770R_REFERENCE, regval);
+}
+
+static int ad5770r_soft_reset(struct ad5770r_state *st)
+{
+       return regmap_write(st->regmap, ADI_SPI_IF_CONFIG_A,
+                           ADI_SPI_IF_SW_RESET_SEL(1));
+}
+
+static int ad5770r_reset(struct ad5770r_state *st)
+{
+       /* Perform software reset if no GPIO provided */
+       if (!st->gpio_reset)
+               return ad5770r_soft_reset(st);
+
+       gpiod_set_value_cansleep(st->gpio_reset, 0);
+       usleep_range(10, 20);
+       gpiod_set_value_cansleep(st->gpio_reset, 1);
+
+       /* data must not be written during reset timeframe */
+       usleep_range(100, 200);
+
+       return 0;
+}
+
+static int ad5770r_get_range(struct ad5770r_state *st,
+                            int ch, int *min, int *max)
+{
+       int i;
+       u8 tbl_ch, tbl_mode, out_range;
+
+       out_range = st->output_mode[ch].out_range_mode;
+
+       for (i = 0; i < AD5770R_MAX_CH_MODES; i++) {
+               tbl_ch = ad5770r_rng_tbl[i].ch;
+               tbl_mode = ad5770r_rng_tbl[i].mode;
+               if (tbl_ch == ch && tbl_mode == out_range) {
+                       *min = ad5770r_rng_tbl[i].min;
+                       *max = ad5770r_rng_tbl[i].max;
+                       return 0;
+               }
+       }
+
+       return -EINVAL;
+}
+
+static int ad5770r_get_filter_freq(struct iio_dev *indio_dev,
+                                  const struct iio_chan_spec *chan, int *freq)
+{
+       struct ad5770r_state *st = iio_priv(indio_dev);
+       int ret;
+       unsigned int regval, i;
+
+       ret = regmap_read(st->regmap,
+                         AD5770R_FILTER_RESISTOR(chan->channel), &regval);
+       if (ret < 0)
+               return ret;
+
+       for (i = 0; i < ARRAY_SIZE(ad5770r_filter_reg_vals); i++)
+               if (regval == ad5770r_filter_reg_vals[i])
+                       break;
+       if (i == ARRAY_SIZE(ad5770r_filter_reg_vals))
+               return -EINVAL;
+
+       *freq = ad5770r_filter_freqs[i];
+
+       return IIO_VAL_INT;
+}
+
+static int ad5770r_set_filter_freq(struct iio_dev *indio_dev,
+                                  const struct iio_chan_spec *chan,
+                                  unsigned int freq)
+{
+       struct ad5770r_state *st = iio_priv(indio_dev);
+       unsigned int regval, i;
+
+       for (i = 0; i < ARRAY_SIZE(ad5770r_filter_freqs); i++)
+               if (ad5770r_filter_freqs[i] >= freq)
+                       break;
+       if (i == ARRAY_SIZE(ad5770r_filter_freqs))
+               return -EINVAL;
+
+       regval = ad5770r_filter_reg_vals[i];
+
+       return regmap_write(st->regmap, AD5770R_FILTER_RESISTOR(chan->channel),
+                           regval);
+}
+
+static int ad5770r_read_raw(struct iio_dev *indio_dev,
+                           struct iio_chan_spec const *chan,
+                           int *val, int *val2, long info)
+{
+       struct ad5770r_state *st = iio_priv(indio_dev);
+       int max, min, ret;
+       u16 buf16;
+
+       switch (info) {
+       case IIO_CHAN_INFO_RAW:
+               ret = regmap_bulk_read(st->regmap,
+                                      chan->address,
+                                      st->transf_buf, 2);
+               if (ret)
+                       return 0;
+
+               buf16 = st->transf_buf[0] + (st->transf_buf[1] << 8);
+               *val = buf16 >> 2;
+               return IIO_VAL_INT;
+       case IIO_CHAN_INFO_SCALE:
+               ret = ad5770r_get_range(st, chan->channel, &min, &max);
+               if (ret < 0)
+                       return ret;
+               *val = max - min;
+               /* There is no sign bit. (negative current is mapped from 0)
+                * (sourced/sinked) current = raw * scale + offset
+                * where offset in case of CH0 can be negative.
+                */
+               *val2 = 14;
+               return IIO_VAL_FRACTIONAL_LOG2;
+       case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
+               return ad5770r_get_filter_freq(indio_dev, chan, val);
+       case IIO_CHAN_INFO_OFFSET:
+               ret = ad5770r_get_range(st, chan->channel, &min, &max);
+               if (ret < 0)
+                       return ret;
+               *val = min;
+               return IIO_VAL_INT;
+       default:
+               return -EINVAL;
+       }
+}
+
+static int ad5770r_write_raw(struct iio_dev *indio_dev,
+                            struct iio_chan_spec const *chan,
+                            int val, int val2, long info)
+{
+       struct ad5770r_state *st = iio_priv(indio_dev);
+
+       switch (info) {
+       case IIO_CHAN_INFO_RAW:
+               st->transf_buf[0] = ((u16)val >> 6);
+               st->transf_buf[1] = (val & GENMASK(5, 0)) << 2;
+               return regmap_bulk_write(st->regmap, chan->address,
+                                        st->transf_buf, 2);
+       case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
+               return ad5770r_set_filter_freq(indio_dev, chan, val);
+       default:
+               return -EINVAL;
+       }
+}
+
+static int ad5770r_read_freq_avail(struct iio_dev *indio_dev,
+                                  struct iio_chan_spec const *chan,
+                                  const int **vals, int *type, int *length,
+                                  long mask)
+{
+       switch (mask) {
+       case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
+               *type = IIO_VAL_INT;
+               *vals = ad5770r_filter_freqs;
+               *length = ARRAY_SIZE(ad5770r_filter_freqs);
+               return IIO_AVAIL_LIST;
+       }
+
+       return -EINVAL;
+}
+
+static int ad5770r_reg_access(struct iio_dev *indio_dev,
+                             unsigned int reg,
+                             unsigned int writeval,
+                             unsigned int *readval)
+{
+       struct ad5770r_state *st = iio_priv(indio_dev);
+
+       if (readval)
+               return regmap_read(st->regmap, reg, readval);
+       else
+               return regmap_write(st->regmap, reg, writeval);
+}
+
+static const struct iio_info ad5770r_info = {
+       .read_raw = ad5770r_read_raw,
+       .write_raw = ad5770r_write_raw,
+       .read_avail = ad5770r_read_freq_avail,
+       .debugfs_reg_access = &ad5770r_reg_access,
+};
+
+static int ad5770r_store_output_range(struct ad5770r_state *st,
+                                     int min, int max, int index)
+{
+       int i;
+
+       for (i = 0; i < AD5770R_MAX_CH_MODES; i++) {
+               if (ad5770r_rng_tbl[i].ch != index)
+                       continue;
+               if (ad5770r_rng_tbl[i].min != min ||
+                   ad5770r_rng_tbl[i].max != max)
+                       continue;
+               st->output_mode[index].out_range_mode = ad5770r_rng_tbl[i].mode;
+
+               return 0;
+       }
+
+       return -EINVAL;
+}
+
+static ssize_t ad5770r_read_dac_powerdown(struct iio_dev *indio_dev,
+                                         uintptr_t private,
+                                         const struct iio_chan_spec *chan,
+                                         char *buf)
+{
+       struct ad5770r_state *st = iio_priv(indio_dev);
+
+       return sprintf(buf, "%d\n", st->ch_pwr_down[chan->channel]);
+}
+
+static ssize_t ad5770r_write_dac_powerdown(struct iio_dev *indio_dev,
+                                          uintptr_t private,
+                                          const struct iio_chan_spec *chan,
+                                          const char *buf, size_t len)
+{
+       struct ad5770r_state *st = iio_priv(indio_dev);
+       unsigned int regval;
+       unsigned int mask;
+       bool readin;
+       int ret;
+
+       ret = kstrtobool(buf, &readin);
+       if (ret)
+               return ret;
+
+       readin = !readin;
+
+       regval = AD5770R_CFG_SHUTDOWN_B(readin, chan->channel);
+       if (chan->channel == 0 &&
+           st->output_mode[0].out_range_mode > AD5770R_CH0_0_300) {
+               regval |= AD5770R_CFG_CH0_SINK_EN(readin);
+               mask = BIT(chan->channel) + BIT(7);
+       } else {
+               mask = BIT(chan->channel);
+       }
+       ret = regmap_update_bits(st->regmap, AD5770R_CHANNEL_CONFIG, mask,
+                                regval);
+       if (ret)
+               return ret;
+
+       regval = AD5770R_CH_SET(readin, chan->channel);
+       ret = regmap_update_bits(st->regmap, AD5770R_CH_ENABLE,
+                                BIT(chan->channel), regval);
+       if (ret)
+               return ret;
+
+       st->ch_pwr_down[chan->channel] = !readin;
+
+       return len;
+}
+
+static const struct iio_chan_spec_ext_info ad5770r_ext_info[] = {
+       {
+               .name = "powerdown",
+               .read = ad5770r_read_dac_powerdown,
+               .write = ad5770r_write_dac_powerdown,
+               .shared = IIO_SEPARATE,
+       },
+       { }
+};
+
+#define AD5770R_IDAC_CHANNEL(index, reg) {                             \
+       .type = IIO_CURRENT,                                            \
+       .address = reg,                                                 \
+       .indexed = 1,                                                   \
+       .channel = index,                                               \
+       .output = 1,                                                    \
+       .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |                  \
+               BIT(IIO_CHAN_INFO_SCALE) |                              \
+               BIT(IIO_CHAN_INFO_OFFSET) |                             \
+               BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),       \
+       .info_mask_shared_by_type_available =                           \
+               BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),       \
+       .ext_info = ad5770r_ext_info,                                   \
+}
+
+static const struct iio_chan_spec ad5770r_channels[] = {
+       AD5770R_IDAC_CHANNEL(0, AD5770R_DAC_MSB(0)),
+       AD5770R_IDAC_CHANNEL(1, AD5770R_DAC_MSB(1)),
+       AD5770R_IDAC_CHANNEL(2, AD5770R_DAC_MSB(2)),
+       AD5770R_IDAC_CHANNEL(3, AD5770R_DAC_MSB(3)),
+       AD5770R_IDAC_CHANNEL(4, AD5770R_DAC_MSB(4)),
+       AD5770R_IDAC_CHANNEL(5, AD5770R_DAC_MSB(5)),
+};
+
+static int ad5770r_channel_config(struct ad5770r_state *st)
+{
+       int ret, tmp[2], min, max;
+       unsigned int num;
+       struct fwnode_handle *child;
+
+       num = device_get_child_node_count(&st->spi->dev);
+       if (num != AD5770R_MAX_CHANNELS)
+               return -EINVAL;
+
+       device_for_each_child_node(&st->spi->dev, child) {
+               ret = fwnode_property_read_u32(child, "num", &num);
+               if (ret)
+                       return ret;
+               if (num > AD5770R_MAX_CHANNELS)
+                       return -EINVAL;
+
+               ret = fwnode_property_read_u32_array(child,
+                                                    "adi,range-microamp",
+                                                    tmp, 2);
+               if (ret)
+                       return ret;
+
+               min = tmp[0] / 1000;
+               max = tmp[1] / 1000;
+               ret = ad5770r_store_output_range(st, min, max, num);
+               if (ret)
+                       return ret;
+       }
+
+       return ret;
+}
+
+static int ad5770r_init(struct ad5770r_state *st)
+{
+       int ret, i;
+
+       st->gpio_reset = devm_gpiod_get_optional(&st->spi->dev, "reset",
+                                                GPIOD_OUT_HIGH);
+       if (IS_ERR(st->gpio_reset))
+               return PTR_ERR(st->gpio_reset);
+
+       /* Perform a reset */
+       ret = ad5770r_reset(st);
+       if (ret)
+               return ret;
+
+       /* Set output range */
+       ret = ad5770r_channel_config(st);
+       if (ret)
+               return ret;
+
+       for (i = 0; i < AD5770R_MAX_CHANNELS; i++) {
+               ret = ad5770r_set_output_mode(st,  &st->output_mode[i], i);
+               if (ret)
+                       return ret;
+       }
+
+       st->external_res = fwnode_property_read_bool(st->spi->dev.fwnode,
+                                                    "adi,external-resistor");
+
+       ret = ad5770r_set_reference(st);
+       if (ret)
+               return ret;
+
+       /* Set outputs off */
+       ret = regmap_write(st->regmap, AD5770R_CHANNEL_CONFIG, 0x00);
+       if (ret)
+               return ret;
+
+       ret = regmap_write(st->regmap, AD5770R_CH_ENABLE, 0x00);
+       if (ret)
+               return ret;
+
+       for (i = 0; i < AD5770R_MAX_CHANNELS; i++)
+               st->ch_pwr_down[i] = true;
+
+       return ret;
+}
+
+static void ad5770r_disable_regulator(void *data)
+{
+       struct ad5770r_state *st = data;
+
+       regulator_disable(st->vref_reg);
+}
+
+static int ad5770r_probe(struct spi_device *spi)
+{
+       struct ad5770r_state *st;
+       struct iio_dev *indio_dev;
+       struct regmap *regmap;
+       int ret;
+
+       indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
+       if (!indio_dev)
+               return -ENOMEM;
+
+       st = iio_priv(indio_dev);
+       spi_set_drvdata(spi, indio_dev);
+
+       st->spi = spi;
+
+       regmap = devm_regmap_init_spi(spi, &ad5770r_spi_regmap_config);
+       if (IS_ERR(regmap)) {
+               dev_err(&spi->dev, "Error initializing spi regmap: %ld\n",
+                       PTR_ERR(regmap));
+               return PTR_ERR(regmap);
+       }
+       st->regmap = regmap;
+
+       st->vref_reg = devm_regulator_get_optional(&spi->dev, "vref");
+       if (!IS_ERR(st->vref_reg)) {
+               ret = regulator_enable(st->vref_reg);
+               if (ret) {
+                       dev_err(&spi->dev,
+                               "Failed to enable vref regulators: %d\n", ret);
+                       return ret;
+               }
+
+               ret = devm_add_action_or_reset(&spi->dev,
+                                              ad5770r_disable_regulator,
+                                              st);
+               if (ret < 0)
+                       return ret;
+
+               ret = regulator_get_voltage(st->vref_reg);
+               if (ret < 0)
+                       return ret;
+
+               st->vref = ret / 1000;
+       } else {
+               if (PTR_ERR(st->vref_reg) == -ENODEV) {
+                       st->vref = AD5770R_LOW_VREF_mV;
+                       st->internal_ref = true;
+               } else {
+                       return PTR_ERR(st->vref_reg);
+               }
+       }
+
+       indio_dev->dev.parent = &spi->dev;
+       indio_dev->name = spi_get_device_id(spi)->name;
+       indio_dev->info = &ad5770r_info;
+       indio_dev->modes = INDIO_DIRECT_MODE;
+       indio_dev->channels = ad5770r_channels;
+       indio_dev->num_channels = ARRAY_SIZE(ad5770r_channels);
+
+       ret = ad5770r_init(st);
+       if (ret < 0) {
+               dev_err(&spi->dev, "AD5770R init failed\n");
+               return ret;
+       }
+
+       return devm_iio_device_register(&st->spi->dev, indio_dev);
+}
+
+static const struct of_device_id ad5770r_of_id[] = {
+       { .compatible = "adi,ad5770r", },
+       {},
+};
+MODULE_DEVICE_TABLE(of, ad5770r_of_id);
+
+static const struct spi_device_id ad5770r_id[] = {
+       { "ad5770r", 0 },
+       {},
+};
+MODULE_DEVICE_TABLE(spi, ad5770r_id);
+
+static struct spi_driver ad5770r_driver = {
+       .driver = {
+               .name = KBUILD_MODNAME,
+               .of_match_table = ad5770r_of_id,
+       },
+       .probe = ad5770r_probe,
+       .id_table = ad5770r_id,
+};
+
+module_spi_driver(ad5770r_driver);
+
+MODULE_AUTHOR("Mircea Caprioru <mircea.caprioru@analog.com>");
+MODULE_DESCRIPTION("Analog Devices AD5770R IDAC");
+MODULE_LICENSE("GPL v2");