root/drivers/iio/dac/ad5686.c
// SPDX-License-Identifier: GPL-2.0
/*
 * AD5686R, AD5685R, AD5684R Digital to analog converters  driver
 *
 * Copyright 2011 Analog Devices Inc.
 */

#include <linux/interrupt.h>
#include <linux/fs.h>
#include <linux/device.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/sysfs.h>
#include <linux/regulator/consumer.h>

#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>

#include "ad5686.h"

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)
{
        struct ad5686_state *st = iio_priv(indio_dev);

        return ((st->pwr_down_mode >> (chan->channel * 2)) & 0x3) - 1;
}

static int ad5686_set_powerdown_mode(struct iio_dev *indio_dev,
                                     const struct iio_chan_spec *chan,
                                     unsigned int mode)
{
        struct ad5686_state *st = iio_priv(indio_dev);

        st->pwr_down_mode &= ~(0x3 << (chan->channel * 2));
        st->pwr_down_mode |= ((mode + 1) << (chan->channel * 2));

        return 0;
}

static const struct iio_enum ad5686_powerdown_mode_enum = {
        .items = ad5686_powerdown_modes,
        .num_items = ARRAY_SIZE(ad5686_powerdown_modes),
        .get = ad5686_get_powerdown_mode,
        .set = ad5686_set_powerdown_mode,
};

static ssize_t ad5686_read_dac_powerdown(struct iio_dev *indio_dev,
                uintptr_t private, const struct iio_chan_spec *chan, char *buf)
{
        struct ad5686_state *st = iio_priv(indio_dev);

        return sysfs_emit(buf, "%d\n", !!(st->pwr_down_mask &
                                       (0x3 << (chan->channel * 2))));
}

static ssize_t ad5686_write_dac_powerdown(struct iio_dev *indio_dev,
                                          uintptr_t private,
                                          const struct iio_chan_spec *chan,
                                          const char *buf,
                                          size_t len)
{
        bool readin;
        int ret;
        struct ad5686_state *st = iio_priv(indio_dev);
        unsigned int val, ref_bit_msk;
        u8 shift, address = 0;

        ret = kstrtobool(buf, &readin);
        if (ret)
                return ret;

        if (readin)
                st->pwr_down_mask |= (0x3 << (chan->channel * 2));
        else
                st->pwr_down_mask &= ~(0x3 << (chan->channel * 2));

        switch (st->chip_info->regmap_type) {
        case AD5310_REGMAP:
                shift = 9;
                ref_bit_msk = AD5310_REF_BIT_MSK;
                break;
        case AD5683_REGMAP:
                shift = 13;
                ref_bit_msk = AD5683_REF_BIT_MSK;
                break;
        case AD5686_REGMAP:
                shift = 0;
                ref_bit_msk = 0;
                /* AD5674R/AD5679R have 16 channels and 2 powerdown registers */
                if (chan->channel > 0x7)
                        address = 0x8;
                break;
        case AD5693_REGMAP:
                shift = 13;
                ref_bit_msk = AD5693_REF_BIT_MSK;
                break;
        default:
                return -EINVAL;
        }

        val = ((st->pwr_down_mask & st->pwr_down_mode) << shift);
        if (!st->use_internal_vref)
                val |= ref_bit_msk;

        ret = st->write(st, AD5686_CMD_POWERDOWN_DAC,
                        address, val >> (address * 2));

        return ret ? ret : len;
}

static int ad5686_read_raw(struct iio_dev *indio_dev,
                           struct iio_chan_spec const *chan,
                           int *val,
                           int *val2,
                           long m)
{
        struct ad5686_state *st = iio_priv(indio_dev);
        int ret;

        switch (m) {
        case IIO_CHAN_INFO_RAW:
                mutex_lock(&st->lock);
                ret = st->read(st, chan->address);
                mutex_unlock(&st->lock);
                if (ret < 0)
                        return ret;
                *val = (ret >> chan->scan_type.shift) &
                        GENMASK(chan->scan_type.realbits - 1, 0);
                return IIO_VAL_INT;
        case IIO_CHAN_INFO_SCALE:
                *val = st->vref_mv;
                *val2 = chan->scan_type.realbits;
                return IIO_VAL_FRACTIONAL_LOG2;
        }
        return -EINVAL;
}

static int ad5686_write_raw(struct iio_dev *indio_dev,
                            struct iio_chan_spec const *chan,
                            int val,
                            int val2,
                            long mask)
{
        struct ad5686_state *st = iio_priv(indio_dev);
        int ret;

        switch (mask) {
        case IIO_CHAN_INFO_RAW:
                if (val > (1 << chan->scan_type.realbits) || val < 0)
                        return -EINVAL;

                mutex_lock(&st->lock);
                ret = st->write(st,
                                AD5686_CMD_WRITE_INPUT_N_UPDATE_N,
                                chan->address,
                                val << chan->scan_type.shift);
                mutex_unlock(&st->lock);
                break;
        default:
                ret = -EINVAL;
        }

        return ret;
}

static const struct iio_info ad5686_info = {
        .read_raw = ad5686_read_raw,
        .write_raw = ad5686_write_raw,
};

static const struct iio_chan_spec_ext_info ad5686_ext_info[] = {
        {
                .name = "powerdown",
                .read = ad5686_read_dac_powerdown,
                .write = ad5686_write_dac_powerdown,
                .shared = IIO_SEPARATE,
        },
        IIO_ENUM("powerdown_mode", IIO_SEPARATE, &ad5686_powerdown_mode_enum),
        IIO_ENUM_AVAILABLE("powerdown_mode", IIO_SHARED_BY_TYPE, &ad5686_powerdown_mode_enum),
        { }
};

#define AD5868_CHANNEL(chan, addr, bits, _shift) {              \
                .type = IIO_VOLTAGE,                            \
                .indexed = 1,                                   \
                .output = 1,                                    \
                .channel = chan,                                \
                .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),   \
                .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),\
                .address = addr,                                \
                .scan_type = {                                  \
                        .sign = 'u',                            \
                        .realbits = (bits),                     \
                        .storagebits = 16,                      \
                        .shift = (_shift),                      \
                },                                              \
                .ext_info = ad5686_ext_info,                    \
}

#define DECLARE_AD5693_CHANNELS(name, bits, _shift)             \
static const struct iio_chan_spec name[] = {                    \
                AD5868_CHANNEL(0, 0, bits, _shift),             \
}

#define DECLARE_AD5338_CHANNELS(name, bits, _shift)             \
static const struct iio_chan_spec name[] = {                    \
                AD5868_CHANNEL(0, 1, bits, _shift),             \
                AD5868_CHANNEL(1, 8, bits, _shift),             \
}

#define DECLARE_AD5686_CHANNELS(name, bits, _shift)             \
static const struct iio_chan_spec name[] = {                    \
                AD5868_CHANNEL(0, 1, bits, _shift),             \
                AD5868_CHANNEL(1, 2, bits, _shift),             \
                AD5868_CHANNEL(2, 4, bits, _shift),             \
                AD5868_CHANNEL(3, 8, bits, _shift),             \
}

#define DECLARE_AD5676_CHANNELS(name, bits, _shift)             \
static const struct iio_chan_spec name[] = {                    \
                AD5868_CHANNEL(0, 0, bits, _shift),             \
                AD5868_CHANNEL(1, 1, bits, _shift),             \
                AD5868_CHANNEL(2, 2, bits, _shift),             \
                AD5868_CHANNEL(3, 3, bits, _shift),             \
                AD5868_CHANNEL(4, 4, bits, _shift),             \
                AD5868_CHANNEL(5, 5, bits, _shift),             \
                AD5868_CHANNEL(6, 6, bits, _shift),             \
                AD5868_CHANNEL(7, 7, bits, _shift),             \
}

#define DECLARE_AD5679_CHANNELS(name, bits, _shift)             \
static const struct iio_chan_spec name[] = {                    \
                AD5868_CHANNEL(0, 0, bits, _shift),             \
                AD5868_CHANNEL(1, 1, bits, _shift),             \
                AD5868_CHANNEL(2, 2, bits, _shift),             \
                AD5868_CHANNEL(3, 3, bits, _shift),             \
                AD5868_CHANNEL(4, 4, bits, _shift),             \
                AD5868_CHANNEL(5, 5, bits, _shift),             \
                AD5868_CHANNEL(6, 6, bits, _shift),             \
                AD5868_CHANNEL(7, 7, bits, _shift),             \
                AD5868_CHANNEL(8, 8, bits, _shift),             \
                AD5868_CHANNEL(9, 9, bits, _shift),             \
                AD5868_CHANNEL(10, 10, bits, _shift),           \
                AD5868_CHANNEL(11, 11, bits, _shift),           \
                AD5868_CHANNEL(12, 12, bits, _shift),           \
                AD5868_CHANNEL(13, 13, bits, _shift),           \
                AD5868_CHANNEL(14, 14, bits, _shift),           \
                AD5868_CHANNEL(15, 15, bits, _shift),           \
}

DECLARE_AD5693_CHANNELS(ad5310r_channels, 10, 2);
DECLARE_AD5693_CHANNELS(ad5311r_channels, 10, 6);
DECLARE_AD5338_CHANNELS(ad5337r_channels, 8, 8);
DECLARE_AD5338_CHANNELS(ad5338r_channels, 10, 6);
DECLARE_AD5676_CHANNELS(ad5672_channels, 12, 4);
DECLARE_AD5679_CHANNELS(ad5674r_channels, 12, 4);
DECLARE_AD5676_CHANNELS(ad5676_channels, 16, 0);
DECLARE_AD5679_CHANNELS(ad5679r_channels, 16, 0);
DECLARE_AD5686_CHANNELS(ad5684_channels, 12, 4);
DECLARE_AD5686_CHANNELS(ad5685r_channels, 14, 2);
DECLARE_AD5686_CHANNELS(ad5686_channels, 16, 0);
DECLARE_AD5693_CHANNELS(ad5693_channels, 16, 0);
DECLARE_AD5693_CHANNELS(ad5692r_channels, 14, 2);
DECLARE_AD5693_CHANNELS(ad5691r_channels, 12, 4);

static const struct ad5686_chip_info ad5686_chip_info_tbl[] = {
        [ID_AD5310R] = {
                .channels = ad5310r_channels,
                .int_vref_mv = 2500,
                .num_channels = 1,
                .regmap_type = AD5310_REGMAP,
        },
        [ID_AD5311R] = {
                .channels = ad5311r_channels,
                .int_vref_mv = 2500,
                .num_channels = 1,
                .regmap_type = AD5693_REGMAP,
        },
        [ID_AD5337R] = {
                .channels = ad5337r_channels,
                .int_vref_mv = 2500,
                .num_channels = 2,
                .regmap_type = AD5686_REGMAP,
        },
        [ID_AD5338R] = {
                .channels = ad5338r_channels,
                .int_vref_mv = 2500,
                .num_channels = 2,
                .regmap_type = AD5686_REGMAP,
        },
        [ID_AD5671R] = {
                .channels = ad5672_channels,
                .int_vref_mv = 2500,
                .num_channels = 8,
                .regmap_type = AD5686_REGMAP,
        },
        [ID_AD5672R] = {
                .channels = ad5672_channels,
                .int_vref_mv = 2500,
                .num_channels = 8,
                .regmap_type = AD5686_REGMAP,
        },
        [ID_AD5673R] = {
                .channels = ad5674r_channels,
                .int_vref_mv = 2500,
                .num_channels = 16,
                .regmap_type = AD5686_REGMAP,
        },
        [ID_AD5674R] = {
                .channels = ad5674r_channels,
                .int_vref_mv = 2500,
                .num_channels = 16,
                .regmap_type = AD5686_REGMAP,
        },
        [ID_AD5675R] = {
                .channels = ad5676_channels,
                .int_vref_mv = 2500,
                .num_channels = 8,
                .regmap_type = AD5686_REGMAP,
        },
        [ID_AD5676] = {
                .channels = ad5676_channels,
                .num_channels = 8,
                .regmap_type = AD5686_REGMAP,
        },
        [ID_AD5676R] = {
                .channels = ad5676_channels,
                .int_vref_mv = 2500,
                .num_channels = 8,
                .regmap_type = AD5686_REGMAP,
        },
        [ID_AD5677R] = {
                .channels = ad5679r_channels,
                .int_vref_mv = 2500,
                .num_channels = 16,
                .regmap_type = AD5686_REGMAP,
        },
        [ID_AD5679R] = {
                .channels = ad5679r_channels,
                .int_vref_mv = 2500,
                .num_channels = 16,
                .regmap_type = AD5686_REGMAP,
        },
        [ID_AD5681R] = {
                .channels = ad5691r_channels,
                .int_vref_mv = 2500,
                .num_channels = 1,
                .regmap_type = AD5683_REGMAP,
        },
        [ID_AD5682R] = {
                .channels = ad5692r_channels,
                .int_vref_mv = 2500,
                .num_channels = 1,
                .regmap_type = AD5683_REGMAP,
        },
        [ID_AD5683] = {
                .channels = ad5693_channels,
                .num_channels = 1,
                .regmap_type = AD5683_REGMAP,
        },
        [ID_AD5683R] = {
                .channels = ad5693_channels,
                .int_vref_mv = 2500,
                .num_channels = 1,
                .regmap_type = AD5683_REGMAP,
        },
        [ID_AD5684] = {
                .channels = ad5684_channels,
                .num_channels = 4,
                .regmap_type = AD5686_REGMAP,
        },
        [ID_AD5684R] = {
                .channels = ad5684_channels,
                .int_vref_mv = 2500,
                .num_channels = 4,
                .regmap_type = AD5686_REGMAP,
        },
        [ID_AD5685R] = {
                .channels = ad5685r_channels,
                .int_vref_mv = 2500,
                .num_channels = 4,
                .regmap_type = AD5686_REGMAP,
        },
        [ID_AD5686] = {
                .channels = ad5686_channels,
                .num_channels = 4,
                .regmap_type = AD5686_REGMAP,
        },
        [ID_AD5686R] = {
                .channels = ad5686_channels,
                .int_vref_mv = 2500,
                .num_channels = 4,
                .regmap_type = AD5686_REGMAP,
        },
        [ID_AD5691R] = {
                .channels = ad5691r_channels,
                .int_vref_mv = 2500,
                .num_channels = 1,
                .regmap_type = AD5693_REGMAP,
        },
        [ID_AD5692R] = {
                .channels = ad5692r_channels,
                .int_vref_mv = 2500,
                .num_channels = 1,
                .regmap_type = AD5693_REGMAP,
        },
        [ID_AD5693] = {
                .channels = ad5693_channels,
                .num_channels = 1,
                .regmap_type = AD5693_REGMAP,
        },
        [ID_AD5693R] = {
                .channels = ad5693_channels,
                .int_vref_mv = 2500,
                .num_channels = 1,
                .regmap_type = AD5693_REGMAP,
        },
        [ID_AD5694] = {
                .channels = ad5684_channels,
                .num_channels = 4,
                .regmap_type = AD5686_REGMAP,
        },
        [ID_AD5694R] = {
                .channels = ad5684_channels,
                .int_vref_mv = 2500,
                .num_channels = 4,
                .regmap_type = AD5686_REGMAP,
        },
        [ID_AD5695R] = {
                .channels = ad5685r_channels,
                .int_vref_mv = 2500,
                .num_channels = 4,
                .regmap_type = AD5686_REGMAP,
        },
        [ID_AD5696] = {
                .channels = ad5686_channels,
                .num_channels = 4,
                .regmap_type = AD5686_REGMAP,
        },
        [ID_AD5696R] = {
                .channels = ad5686_channels,
                .int_vref_mv = 2500,
                .num_channels = 4,
                .regmap_type = AD5686_REGMAP,
        },
};

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;
        unsigned int val, ref_bit_msk;
        bool has_external_vref;
        u8 cmd;
        int ret, i;

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

        st = iio_priv(indio_dev);

        st->dev = dev;
        st->write = write;
        st->read = read;

        st->chip_info = &ad5686_chip_info_tbl[chip_type];

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

        has_external_vref = ret != -ENODEV;
        st->vref_mv = has_external_vref ? ret / 1000 : st->chip_info->int_vref_mv;

        /* Set all the power down mode for all channels to 1K pulldown */
        for (i = 0; i < st->chip_info->num_channels; i++)
                st->pwr_down_mode |= (0x01 << (i * 2));

        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;

        mutex_init(&st->lock);

        switch (st->chip_info->regmap_type) {
        case AD5310_REGMAP:
                cmd = AD5686_CMD_CONTROL_REG;
                ref_bit_msk = AD5310_REF_BIT_MSK;
                st->use_internal_vref = !has_external_vref;
                break;
        case AD5683_REGMAP:
                cmd = AD5686_CMD_CONTROL_REG;
                ref_bit_msk = AD5683_REF_BIT_MSK;
                st->use_internal_vref = !has_external_vref;
                break;
        case AD5686_REGMAP:
                cmd = AD5686_CMD_INTERNAL_REFER_SETUP;
                ref_bit_msk = 0;
                break;
        case AD5693_REGMAP:
                cmd = AD5686_CMD_CONTROL_REG;
                ref_bit_msk = AD5693_REF_BIT_MSK;
                st->use_internal_vref = !has_external_vref;
                break;
        default:
                return -EINVAL;
        }

        val = (has_external_vref | ref_bit_msk);

        ret = st->write(st, cmd, 0, !!val);
        if (ret)
                return ret;

        return devm_iio_device_register(dev, indio_dev);
}
EXPORT_SYMBOL_NS_GPL(ad5686_probe, "IIO_AD5686");

MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
MODULE_DESCRIPTION("Analog Devices AD5686/85/84 DAC");
MODULE_LICENSE("GPL v2");