Re: [PATCH 1/2] iio: dac: ad5770r: Add AD5770R support

From: Ardelean, Alexandru
Date: Tue Feb 11 2020 - 08:52:08 EST

On Sat, 2020-02-08 at 14:33 +0000, Jonathan Cameron wrote:
> On Thu, 6 Feb 2020 11:23:12 +0200
> Alexandru Tachici <alexandru.tachici@xxxxxxxxxx> wrote:
>
> > 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.
>
> I'd like to see considerably more discussion of the common header.
> What devices do these shared registers apply to?
> Current header naming kind of implies all ADI devices with an
> spi interface which I find very unlikely.

Right.
My bad here, since I don't think I provided AlexandruT the full details on this.

We'll see about a V3 with some reference for these.

Thanks
Alex

>
> Otherwise one minor comment inline.
>
> Thanks,
>
> Jonathan
>
>
> > Signed-off-by: Mircea Caprioru <mircea.caprioru@xxxxxxxxxx>
> > Signed-off-by: Alexandru Tachici <alexandru.tachici@xxxxxxxxxx>
> > ---
> > drivers/iio/dac/Kconfig | 10 +
> > drivers/iio/dac/Makefile | 1 +
> > drivers/iio/dac/ad5770r.c | 662 ++++++++++++++++++++++++
> > include/linux/iio/common/adi_spi_regs.h | 44 ++
> > 4 files changed, 717 insertions(+)
> > create mode 100644 drivers/iio/dac/ad5770r.c
> > create mode 100644 include/linux/iio/common/adi_spi_regs.h
> >
> > diff --git a/drivers/iio/dac/Kconfig b/drivers/iio/dac/Kconfig
> > index 979070196da9..c74f2151ee42 100644
> > --- a/drivers/iio/dac/Kconfig
> > +++ b/drivers/iio/dac/Kconfig
> > @@ -208,6 +208,16 @@ 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
> > diff --git a/drivers/iio/dac/Makefile b/drivers/iio/dac/Makefile
> > index 1369fa1d2f0e..2fc481167724 100644
> > --- a/drivers/iio/dac/Makefile
> > +++ b/drivers/iio/dac/Makefile
> > @@ -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
> > index 000000000000..a8b2c1850ffd
> > --- /dev/null
> > +++ b/drivers/iio/dac/ad5770r.c
> > @@ -0,0 +1,662 @@
> > +// SPDX-License-Identifier: GPL-2.0+
> > +/*
> > + * AD5770R Digital to analog converters driver
> > + *
> > + * Copyright 2018 Analog Devices Inc.
> > + */
> > +
> > +#include <linux/delay.h>
> > +#include <linux/device.h>
> > +#include <linux/gpio/consumer.h>
> > +#include <linux/iio/common/adi_spi_regs.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>
> > +
> > +/* 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) & 0x3F) << 2)
> > +#define AD5770R_RANGE_MODE(x) ((x) & 0x03)
> > +
> > +/* AD5770R_REFERENCE */
> > +#define AD5770R_REF_RESISTOR_SEL(x) (((x) & 0x1) << 2)
> > +#define AD5770R_REF_SEL(x) (((x) & 0x3) << 0)
> > +
> > +/* AD5770R_CH_ENABLE */
> > +#define AD5770R_CH_SET(x, channel) (((x) & 0x1) << (channel))
> > +
> > +#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
> > + */
> > +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;
> > +};
> > +
> > +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 = 0;
>
> It's immediately set to something else, so don't initialize it here.
>
> > +
> > + 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;
> > + __le16 buf16;
> > +
> > + switch (info) {
> > + case IIO_CHAN_INFO_RAW:
> > + ret = regmap_bulk_read(st->regmap,
> > + chan->address,
> > + &buf16, 2);
> > + if (ret)
> > + return 0;
> > + *val = le16_to_cpu(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);
> > + u8 buf[2];
> > +
> > + switch (info) {
> > + case IIO_CHAN_INFO_RAW:
> > + buf[0] = ((u16)val >> 6);
> > + buf[1] = (val & 0x3F) << 2;
> > + return regmap_bulk_write(st->regmap, chan->address,
> > + buf, ARRAY_SIZE(buf));
> > + 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 spi_device *spi = (struct spi_device *)data;
> > + struct iio_dev *indio_dev = spi_get_drvdata(spi);
> > + struct ad5770r_state *st = iio_priv(indio_dev);
> > +
> > + if (st->vref_reg)
> > + 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;
> > +
> > + ret = devm_add_action_or_reset(&spi->dev, ad5770r_disable_regulator,
> > + st);
> > + if (ret < 0)
> > + return ret;
> > +
> > + 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 = 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 = of_match_ptr(ad5770r_of_id),
> > + },
> > + .probe = ad5770r_probe,
> > + .id_table = ad5770r_id,
> > +};
> > +
> > +module_spi_driver(ad5770r_driver);
> > +
> > +MODULE_AUTHOR("Mircea Caprioru <mircea.caprioru@xxxxxxxxxx>");
> > +MODULE_DESCRIPTION("Analog Devices AD5770R IDAC");
> > +MODULE_LICENSE("GPL v2");
> > diff --git a/include/linux/iio/common/adi_spi_regs.h
> > b/include/linux/iio/common/adi_spi_regs.h
> > new file mode 100644
> > index 000000000000..1fc3bfc7845d
> > --- /dev/null
> > +++ b/include/linux/iio/common/adi_spi_regs.h
> > @@ -0,0 +1,44 @@
> > +/* SPDX-License-Identifier: GPL-2.0 */
> > +/*
> > + * Common Analog Devices SPI configuration registers
> > + *
> > + * Copyright 2019 Analog Devices Inc.
> > + */
> > +
> > +#ifndef _ADI_SPI_REGS_H_
> > +#define _ADI_SPI_REGS_H_
> > +
> > +#include <linux/bits.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)
> > +
> > +#endif /* _ADI_SPI_REGS_H_ */