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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* AD5446 CORE DAC driver
*
* Copyright 2010 Analog Devices Inc.
*/
#include <linux/array_size.h>
#include <linux/cleanup.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/export.h>
#include <linux/iio/iio.h>
#include <linux/kstrtox.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/regulator/consumer.h>
#include <linux/sysfs.h>
#include "ad5446.h"
#define MODE_PWRDWN_1k 0x1
#define MODE_PWRDWN_100k 0x2
#define MODE_PWRDWN_TRISTATE 0x3
static const char * const ad5446_powerdown_modes[] = {
"1kohm_to_gnd", "100kohm_to_gnd", "three_state"
};
static int ad5446_set_powerdown_mode(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan,
unsigned int mode)
{
struct ad5446_state *st = iio_priv(indio_dev);
st->pwr_down_mode = mode + 1;
return 0;
}
static int ad5446_get_powerdown_mode(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan)
{
struct ad5446_state *st = iio_priv(indio_dev);
return st->pwr_down_mode - 1;
}
static const struct iio_enum ad5446_powerdown_mode_enum = {
.items = ad5446_powerdown_modes,
.num_items = ARRAY_SIZE(ad5446_powerdown_modes),
.get = ad5446_get_powerdown_mode,
.set = ad5446_set_powerdown_mode,
};
static ssize_t ad5446_read_dac_powerdown(struct iio_dev *indio_dev,
uintptr_t private,
const struct iio_chan_spec *chan,
char *buf)
{
struct ad5446_state *st = iio_priv(indio_dev);
return sysfs_emit(buf, "%d\n", st->pwr_down);
}
static ssize_t ad5446_write_dac_powerdown(struct iio_dev *indio_dev,
uintptr_t private,
const struct iio_chan_spec *chan,
const char *buf, size_t len)
{
struct ad5446_state *st = iio_priv(indio_dev);
unsigned int shift;
unsigned int val;
bool powerdown;
int ret;
ret = kstrtobool(buf, &powerdown);
if (ret)
return ret;
guard(mutex)(&st->lock);
st->pwr_down = powerdown;
if (st->pwr_down) {
shift = chan->scan_type.realbits + chan->scan_type.shift;
val = st->pwr_down_mode << shift;
} else {
val = st->cached_val;
}
ret = st->chip_info->write(st, val);
if (ret)
return ret;
return len;
}
const struct iio_chan_spec_ext_info ad5446_ext_info_powerdown[] = {
{
.name = "powerdown",
.read = ad5446_read_dac_powerdown,
.write = ad5446_write_dac_powerdown,
.shared = IIO_SEPARATE,
},
IIO_ENUM("powerdown_mode", IIO_SEPARATE, &ad5446_powerdown_mode_enum),
IIO_ENUM_AVAILABLE("powerdown_mode", IIO_SHARED_BY_TYPE, &ad5446_powerdown_mode_enum),
{ }
};
EXPORT_SYMBOL_NS_GPL(ad5446_ext_info_powerdown, "IIO_AD5446");
static int ad5446_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val,
int *val2,
long m)
{
struct ad5446_state *st = iio_priv(indio_dev);
switch (m) {
case IIO_CHAN_INFO_RAW:
*val = st->cached_val >> chan->scan_type.shift;
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 ad5446_write_dac_raw(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan,
int val)
{
struct ad5446_state *st = iio_priv(indio_dev);
if (val >= (1 << chan->scan_type.realbits) || val < 0)
return -EINVAL;
val <<= chan->scan_type.shift;
guard(mutex)(&st->lock);
st->cached_val = val;
if (st->pwr_down)
return 0;
return st->chip_info->write(st, val);
}
static int ad5446_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan, int val,
int val2, long mask)
{
switch (mask) {
case IIO_CHAN_INFO_RAW:
return ad5446_write_dac_raw(indio_dev, chan, val);
default:
return -EINVAL;
}
}
static const struct iio_info ad5446_info = {
.read_raw = ad5446_read_raw,
.write_raw = ad5446_write_raw,
};
int ad5446_probe(struct device *dev, const char *name,
const struct ad5446_chip_info *chip_info)
{
struct ad5446_state *st;
struct iio_dev *indio_dev;
int ret;
indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
if (!indio_dev)
return -ENOMEM;
st = iio_priv(indio_dev);
st->chip_info = chip_info;
st->dev = dev;
indio_dev->name = name;
indio_dev->info = &ad5446_info;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->channels = &st->chip_info->channel;
indio_dev->num_channels = 1;
ret = devm_mutex_init(dev, &st->lock);
if (ret)
return ret;
st->pwr_down_mode = MODE_PWRDWN_1k;
ret = devm_regulator_get_enable_read_voltage(dev, "vcc");
if (ret < 0 && ret != -ENODEV)
return ret;
if (ret == -ENODEV) {
if (!chip_info->int_vref_mv)
return dev_err_probe(dev, ret,
"reference voltage unspecified\n");
st->vref_mv = chip_info->int_vref_mv;
} else {
st->vref_mv = ret / 1000;
}
return devm_iio_device_register(dev, indio_dev);
}
EXPORT_SYMBOL_NS_GPL(ad5446_probe, "IIO_AD5446");
MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
MODULE_DESCRIPTION("Analog Devices CORE AD5446 DAC and similar devices");
MODULE_LICENSE("GPL v2");
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