#include <linux/interrupt.h>
#include <linux/fs.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/spi/spi.h>
#include <linux/slab.h>
#include <linux/sysfs.h>
#include <linux/regulator/consumer.h>
#include <linux/module.h>
#include <linux/bitops.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/events.h>
#include <linux/iio/dac/ad5504.h>
#define AD5504_RES_MASK GENMASK(11, 0)
#define AD5504_CMD_READ BIT(15)
#define AD5504_CMD_WRITE 0
#define AD5504_ADDR(addr) ((addr) << 12)
#define AD5504_ADDR_NOOP 0
#define AD5504_ADDR_DAC(x) ((x) + 1)
#define AD5504_ADDR_ALL_DAC 5
#define AD5504_ADDR_CTRL 7
#define AD5504_DAC_PWR(ch) ((ch) << 2)
#define AD5504_DAC_PWRDWN_MODE(mode) ((mode) << 6)
#define AD5504_DAC_PWRDN_20K 0
#define AD5504_DAC_PWRDN_3STATE 1
struct ad5504_state {
struct spi_device *spi;
struct regulator *reg;
unsigned short vref_mv;
unsigned pwr_down_mask;
unsigned pwr_down_mode;
__be16 data[2] __aligned(IIO_DMA_MINALIGN);
};
enum ad5504_supported_device_ids {
ID_AD5504,
ID_AD5501,
};
static int ad5504_spi_write(struct ad5504_state *st, u8 addr, u16 val)
{
st->data[0] = cpu_to_be16(AD5504_CMD_WRITE | AD5504_ADDR(addr) |
(val & AD5504_RES_MASK));
return spi_write(st->spi, &st->data[0], 2);
}
static int ad5504_spi_read(struct ad5504_state *st, u8 addr)
{
int ret;
struct spi_transfer t = {
.tx_buf = &st->data[0],
.rx_buf = &st->data[1],
.len = 2,
};
st->data[0] = cpu_to_be16(AD5504_CMD_READ | AD5504_ADDR(addr));
ret = spi_sync_transfer(st->spi, &t, 1);
if (ret < 0)
return ret;
return be16_to_cpu(st->data[1]) & AD5504_RES_MASK;
}
static int ad5504_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val,
int *val2,
long m)
{
struct ad5504_state *st = iio_priv(indio_dev);
int ret;
switch (m) {
case IIO_CHAN_INFO_RAW:
ret = ad5504_spi_read(st, chan->address);
if (ret < 0)
return ret;
*val = ret;
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 ad5504_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int val,
int val2,
long mask)
{
struct ad5504_state *st = iio_priv(indio_dev);
switch (mask) {
case IIO_CHAN_INFO_RAW:
if (val >= (1 << chan->scan_type.realbits) || val < 0)
return -EINVAL;
return ad5504_spi_write(st, chan->address, val);
default:
return -EINVAL;
}
}
static const char * const ad5504_powerdown_modes[] = {
"20kohm_to_gnd",
"three_state",
};
static int ad5504_get_powerdown_mode(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan)
{
struct ad5504_state *st = iio_priv(indio_dev);
return st->pwr_down_mode;
}
static int ad5504_set_powerdown_mode(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan, unsigned int mode)
{
struct ad5504_state *st = iio_priv(indio_dev);
st->pwr_down_mode = mode;
return 0;
}
static const struct iio_enum ad5504_powerdown_mode_enum = {
.items = ad5504_powerdown_modes,
.num_items = ARRAY_SIZE(ad5504_powerdown_modes),
.get = ad5504_get_powerdown_mode,
.set = ad5504_set_powerdown_mode,
};
static ssize_t ad5504_read_dac_powerdown(struct iio_dev *indio_dev,
uintptr_t private, const struct iio_chan_spec *chan, char *buf)
{
struct ad5504_state *st = iio_priv(indio_dev);
return sysfs_emit(buf, "%d\n",
!(st->pwr_down_mask & (1 << chan->channel)));
}
static ssize_t ad5504_write_dac_powerdown(struct iio_dev *indio_dev,
uintptr_t private, const struct iio_chan_spec *chan, const char *buf,
size_t len)
{
bool pwr_down;
int ret;
struct ad5504_state *st = iio_priv(indio_dev);
ret = kstrtobool(buf, &pwr_down);
if (ret)
return ret;
if (pwr_down)
st->pwr_down_mask &= ~(1 << chan->channel);
else
st->pwr_down_mask |= (1 << chan->channel);
ret = ad5504_spi_write(st, AD5504_ADDR_CTRL,
AD5504_DAC_PWRDWN_MODE(st->pwr_down_mode) |
AD5504_DAC_PWR(st->pwr_down_mask));
ad5504_spi_write(st, AD5504_ADDR_NOOP, 0);
return ret ? ret : len;
}
static IIO_CONST_ATTR(temp0_thresh_rising_value, "110000");
static IIO_CONST_ATTR(temp0_thresh_rising_en, "1");
static struct attribute *ad5504_ev_attributes[] = {
&iio_const_attr_temp0_thresh_rising_value.dev_attr.attr,
&iio_const_attr_temp0_thresh_rising_en.dev_attr.attr,
NULL,
};
static const struct attribute_group ad5504_ev_attribute_group = {
.attrs = ad5504_ev_attributes,
};
static irqreturn_t ad5504_event_handler(int irq, void *private)
{
iio_push_event(private,
IIO_UNMOD_EVENT_CODE(IIO_TEMP,
0,
IIO_EV_TYPE_THRESH,
IIO_EV_DIR_RISING),
iio_get_time_ns(private));
return IRQ_HANDLED;
}
static const struct iio_info ad5504_info = {
.write_raw = ad5504_write_raw,
.read_raw = ad5504_read_raw,
.event_attrs = &ad5504_ev_attribute_group,
};
static const struct iio_chan_spec_ext_info ad5504_ext_info[] = {
{
.name = "powerdown",
.read = ad5504_read_dac_powerdown,
.write = ad5504_write_dac_powerdown,
.shared = IIO_SEPARATE,
},
IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE,
&ad5504_powerdown_mode_enum),
IIO_ENUM_AVAILABLE("powerdown_mode", IIO_SHARED_BY_TYPE, &ad5504_powerdown_mode_enum),
{ }
};
#define AD5504_CHANNEL(_chan) { \
.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 = AD5504_ADDR_DAC(_chan), \
.scan_type = { \
.sign = 'u', \
.realbits = 12, \
.storagebits = 16, \
}, \
.ext_info = ad5504_ext_info, \
}
static const struct iio_chan_spec ad5504_channels[] = {
AD5504_CHANNEL(0),
AD5504_CHANNEL(1),
AD5504_CHANNEL(2),
AD5504_CHANNEL(3),
};
static int ad5504_probe(struct spi_device *spi)
{
const struct ad5504_platform_data *pdata = dev_get_platdata(&spi->dev);
struct iio_dev *indio_dev;
struct ad5504_state *st;
int ret;
indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
if (!indio_dev)
return -ENOMEM;
st = iio_priv(indio_dev);
ret = devm_regulator_get_enable_read_voltage(&spi->dev, "vcc");
if (ret < 0 && ret != -ENODEV)
return ret;
if (ret == -ENODEV) {
if (pdata->vref_mv)
st->vref_mv = pdata->vref_mv;
else
dev_warn(&spi->dev, "reference voltage unspecified\n");
} else {
st->vref_mv = ret / 1000;
}
st->spi = spi;
indio_dev->name = spi_get_device_id(st->spi)->name;
indio_dev->info = &ad5504_info;
if (spi_get_device_id(st->spi)->driver_data == ID_AD5501)
indio_dev->num_channels = 1;
else
indio_dev->num_channels = 4;
indio_dev->channels = ad5504_channels;
indio_dev->modes = INDIO_DIRECT_MODE;
if (spi->irq) {
ret = devm_request_threaded_irq(&spi->dev, spi->irq,
NULL,
&ad5504_event_handler,
IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
spi_get_device_id(st->spi)->name,
indio_dev);
if (ret)
return ret;
}
return devm_iio_device_register(&spi->dev, indio_dev);
}
static const struct spi_device_id ad5504_id[] = {
{"ad5504", ID_AD5504},
{"ad5501", ID_AD5501},
{ }
};
MODULE_DEVICE_TABLE(spi, ad5504_id);
static struct spi_driver ad5504_driver = {
.driver = {
.name = "ad5504",
},
.probe = ad5504_probe,
.id_table = ad5504_id,
};
module_spi_driver(ad5504_driver);
MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
MODULE_DESCRIPTION("Analog Devices AD5501/AD5501 DAC");
MODULE_LICENSE("GPL v2");
