linux/drivers/iio/dac/ad5758.c
Stefan Popa 28d1a7ac2a iio: dac: Add AD5758 support
The AD5758 is a single channel DAC with 16-bit precision which uses the
SPI interface that operates at clock rates up to 50MHz.

The output can be configured as voltage or current and is available on a
single terminal.

Datasheet:
http://www.analog.com/media/en/technical-documentation/data-sheets/ad5758.pdf

Signed-off-by: Stefan Popa <stefan.popa@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2018-07-07 18:16:32 +01:00

898 lines
22 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* AD5758 Digital to analog converters driver
*
* Copyright 2018 Analog Devices Inc.
*
* TODO: Currently CRC is not supported in this driver
*/
#include <linux/bsearch.h>
#include <linux/delay.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/property.h>
#include <linux/spi/spi.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
/* AD5758 registers definition */
#define AD5758_NOP 0x00
#define AD5758_DAC_INPUT 0x01
#define AD5758_DAC_OUTPUT 0x02
#define AD5758_CLEAR_CODE 0x03
#define AD5758_USER_GAIN 0x04
#define AD5758_USER_OFFSET 0x05
#define AD5758_DAC_CONFIG 0x06
#define AD5758_SW_LDAC 0x07
#define AD5758_KEY 0x08
#define AD5758_GP_CONFIG1 0x09
#define AD5758_GP_CONFIG2 0x0A
#define AD5758_DCDC_CONFIG1 0x0B
#define AD5758_DCDC_CONFIG2 0x0C
#define AD5758_WDT_CONFIG 0x0F
#define AD5758_DIGITAL_DIAG_CONFIG 0x10
#define AD5758_ADC_CONFIG 0x11
#define AD5758_FAULT_PIN_CONFIG 0x12
#define AD5758_TWO_STAGE_READBACK_SELECT 0x13
#define AD5758_DIGITAL_DIAG_RESULTS 0x14
#define AD5758_ANALOG_DIAG_RESULTS 0x15
#define AD5758_STATUS 0x16
#define AD5758_CHIP_ID 0x17
#define AD5758_FREQ_MONITOR 0x18
#define AD5758_DEVICE_ID_0 0x19
#define AD5758_DEVICE_ID_1 0x1A
#define AD5758_DEVICE_ID_2 0x1B
#define AD5758_DEVICE_ID_3 0x1C
/* AD5758_DAC_CONFIG */
#define AD5758_DAC_CONFIG_RANGE_MSK GENMASK(3, 0)
#define AD5758_DAC_CONFIG_RANGE_MODE(x) (((x) & 0xF) << 0)
#define AD5758_DAC_CONFIG_INT_EN_MSK BIT(5)
#define AD5758_DAC_CONFIG_INT_EN_MODE(x) (((x) & 0x1) << 5)
#define AD5758_DAC_CONFIG_OUT_EN_MSK BIT(6)
#define AD5758_DAC_CONFIG_OUT_EN_MODE(x) (((x) & 0x1) << 6)
#define AD5758_DAC_CONFIG_SR_EN_MSK BIT(8)
#define AD5758_DAC_CONFIG_SR_EN_MODE(x) (((x) & 0x1) << 8)
#define AD5758_DAC_CONFIG_SR_CLOCK_MSK GENMASK(12, 9)
#define AD5758_DAC_CONFIG_SR_CLOCK_MODE(x) (((x) & 0xF) << 9)
#define AD5758_DAC_CONFIG_SR_STEP_MSK GENMASK(15, 13)
#define AD5758_DAC_CONFIG_SR_STEP_MODE(x) (((x) & 0x7) << 13)
/* AD5758_KEY */
#define AD5758_KEY_CODE_RESET_1 0x15FA
#define AD5758_KEY_CODE_RESET_2 0xAF51
#define AD5758_KEY_CODE_SINGLE_ADC_CONV 0x1ADC
#define AD5758_KEY_CODE_RESET_WDT 0x0D06
#define AD5758_KEY_CODE_CALIB_MEM_REFRESH 0xFCBA
/* AD5758_DCDC_CONFIG1 */
#define AD5758_DCDC_CONFIG1_DCDC_VPROG_MSK GENMASK(4, 0)
#define AD5758_DCDC_CONFIG1_DCDC_VPROG_MODE(x) (((x) & 0x1F) << 0)
#define AD5758_DCDC_CONFIG1_DCDC_MODE_MSK GENMASK(6, 5)
#define AD5758_DCDC_CONFIG1_DCDC_MODE_MODE(x) (((x) & 0x3) << 5)
#define AD5758_DCDC_CONFIG1_PROT_SW_EN_MSK BIT(7)
#define AD5758_DCDC_CONFIG1_PROT_SW_EN_MODE(x) (((x) & 0x1) << 7)
/* AD5758_DCDC_CONFIG2 */
#define AD5758_DCDC_CONFIG2_ILIMIT_MSK GENMASK(3, 1)
#define AD5758_DCDC_CONFIG2_ILIMIT_MODE(x) (((x) & 0x7) << 1)
#define AD5758_DCDC_CONFIG2_INTR_SAT_3WI_MSK BIT(11)
#define AD5758_DCDC_CONFIG2_BUSY_3WI_MSK BIT(12)
/* AD5758_DIGITAL_DIAG_RESULTS */
#define AD5758_CAL_MEM_UNREFRESHED_MSK BIT(15)
#define AD5758_WR_FLAG_MSK(x) (0x80 | ((x) & 0x1F))
#define AD5758_FULL_SCALE_MICRO 65535000000ULL
/**
* struct ad5758_state - driver instance specific data
* @spi: spi_device
* @lock: mutex lock
* @out_range: struct which stores the output range
* @dc_dc_mode: variable which stores the mode of operation
* @dc_dc_ilim: variable which stores the dc-to-dc converter current limit
* @slew_time: variable which stores the target slew time
* @pwr_down: variable which contains whether a channel is powered down or not
* @data: spi transfer buffers
*/
struct ad5758_range {
int reg;
int min;
int max;
};
struct ad5758_state {
struct spi_device *spi;
struct mutex lock;
struct ad5758_range out_range;
unsigned int dc_dc_mode;
unsigned int dc_dc_ilim;
unsigned int slew_time;
bool pwr_down;
__be32 d32[3];
};
/**
* Output ranges corresponding to bits [3:0] from DAC_CONFIG register
* 0000: 0 V to 5 V voltage range
* 0001: 0 V to 10 V voltage range
* 0010: ±5 V voltage range
* 0011: ±10 V voltage range
* 1000: 0 mA to 20 mA current range
* 1001: 0 mA to 24 mA current range
* 1010: 4 mA to 20 mA current range
* 1011: ±20 mA current range
* 1100: ±24 mA current range
* 1101: -1 mA to +22 mA current range
*/
enum ad5758_output_range {
AD5758_RANGE_0V_5V,
AD5758_RANGE_0V_10V,
AD5758_RANGE_PLUSMINUS_5V,
AD5758_RANGE_PLUSMINUS_10V,
AD5758_RANGE_0mA_20mA = 8,
AD5758_RANGE_0mA_24mA,
AD5758_RANGE_4mA_24mA,
AD5758_RANGE_PLUSMINUS_20mA,
AD5758_RANGE_PLUSMINUS_24mA,
AD5758_RANGE_MINUS_1mA_PLUS_22mA,
};
enum ad5758_dc_dc_mode {
AD5758_DCDC_MODE_POWER_OFF,
AD5758_DCDC_MODE_DPC_CURRENT,
AD5758_DCDC_MODE_DPC_VOLTAGE,
AD5758_DCDC_MODE_PPC_CURRENT,
};
static const struct ad5758_range ad5758_voltage_range[] = {
{ AD5758_RANGE_0V_5V, 0, 5000000 },
{ AD5758_RANGE_0V_10V, 0, 10000000 },
{ AD5758_RANGE_PLUSMINUS_5V, -5000000, 5000000 },
{ AD5758_RANGE_PLUSMINUS_10V, -10000000, 10000000 }
};
static const struct ad5758_range ad5758_current_range[] = {
{ AD5758_RANGE_0mA_20mA, 0, 20000},
{ AD5758_RANGE_0mA_24mA, 0, 24000 },
{ AD5758_RANGE_4mA_24mA, 4, 24000 },
{ AD5758_RANGE_PLUSMINUS_20mA, -20000, 20000 },
{ AD5758_RANGE_PLUSMINUS_24mA, -24000, 24000 },
{ AD5758_RANGE_MINUS_1mA_PLUS_22mA, -1000, 22000 },
};
static const int ad5758_sr_clk[16] = {
240000, 200000, 150000, 128000, 64000, 32000, 16000, 8000, 4000, 2000,
1000, 512, 256, 128, 64, 16
};
static const int ad5758_sr_step[8] = {
4, 12, 64, 120, 256, 500, 1820, 2048
};
static const int ad5758_dc_dc_ilim[6] = {
150000, 200000, 250000, 300000, 350000, 400000
};
static int ad5758_spi_reg_read(struct ad5758_state *st, unsigned int addr)
{
struct spi_transfer t[] = {
{
.tx_buf = &st->d32[0],
.len = 4,
.cs_change = 1,
}, {
.tx_buf = &st->d32[1],
.rx_buf = &st->d32[2],
.len = 4,
},
};
int ret;
st->d32[0] = cpu_to_be32(
(AD5758_WR_FLAG_MSK(AD5758_TWO_STAGE_READBACK_SELECT) << 24) |
(addr << 8));
st->d32[1] = cpu_to_be32(AD5758_WR_FLAG_MSK(AD5758_NOP) << 24);
ret = spi_sync_transfer(st->spi, t, ARRAY_SIZE(t));
if (ret < 0)
return ret;
return (be32_to_cpu(st->d32[2]) >> 8) & 0xFFFF;
}
static int ad5758_spi_reg_write(struct ad5758_state *st,
unsigned int addr,
unsigned int val)
{
st->d32[0] = cpu_to_be32((AD5758_WR_FLAG_MSK(addr) << 24) |
((val & 0xFFFF) << 8));
return spi_write(st->spi, &st->d32[0], sizeof(st->d32[0]));
}
static int ad5758_spi_write_mask(struct ad5758_state *st,
unsigned int addr,
unsigned long int mask,
unsigned int val)
{
int regval;
regval = ad5758_spi_reg_read(st, addr);
if (regval < 0)
return regval;
regval &= ~mask;
regval |= val;
return ad5758_spi_reg_write(st, addr, regval);
}
static int cmpfunc(const void *a, const void *b)
{
return *(int *)a - *(int *)b;
}
static int ad5758_find_closest_match(const int *array,
unsigned int size, int val)
{
int i;
for (i = 0; i < size; i++) {
if (val <= array[i])
return i;
}
return size - 1;
}
static int ad5758_wait_for_task_complete(struct ad5758_state *st,
unsigned int reg,
unsigned int mask)
{
unsigned int timeout;
int ret;
timeout = 10;
do {
ret = ad5758_spi_reg_read(st, reg);
if (ret < 0)
return ret;
if (!(ret & mask))
return 0;
usleep_range(100, 1000);
} while (--timeout);
dev_err(&st->spi->dev,
"Error reading bit 0x%x in 0x%x register\n", mask, reg);
return -EIO;
}
static int ad5758_calib_mem_refresh(struct ad5758_state *st)
{
int ret;
ret = ad5758_spi_reg_write(st, AD5758_KEY,
AD5758_KEY_CODE_CALIB_MEM_REFRESH);
if (ret < 0) {
dev_err(&st->spi->dev,
"Failed to initiate a calibration memory refresh\n");
return ret;
}
/* Wait to allow time for the internal calibrations to complete */
return ad5758_wait_for_task_complete(st, AD5758_DIGITAL_DIAG_RESULTS,
AD5758_CAL_MEM_UNREFRESHED_MSK);
}
static int ad5758_soft_reset(struct ad5758_state *st)
{
int ret;
ret = ad5758_spi_reg_write(st, AD5758_KEY, AD5758_KEY_CODE_RESET_1);
if (ret < 0)
return ret;
ret = ad5758_spi_reg_write(st, AD5758_KEY, AD5758_KEY_CODE_RESET_2);
/* Perform a software reset and wait at least 100us */
usleep_range(100, 1000);
return ret;
}
static int ad5758_set_dc_dc_conv_mode(struct ad5758_state *st,
enum ad5758_dc_dc_mode mode)
{
int ret;
ret = ad5758_spi_write_mask(st, AD5758_DCDC_CONFIG1,
AD5758_DCDC_CONFIG1_DCDC_MODE_MSK,
AD5758_DCDC_CONFIG1_DCDC_MODE_MODE(mode));
if (ret < 0)
return ret;
/*
* Poll the BUSY_3WI bit in the DCDC_CONFIG2 register until it is 0.
* This allows the 3-wire interface communication to complete.
*/
ret = ad5758_wait_for_task_complete(st, AD5758_DCDC_CONFIG2,
AD5758_DCDC_CONFIG2_BUSY_3WI_MSK);
if (ret < 0)
return ret;
st->dc_dc_mode = mode;
return ret;
}
static int ad5758_set_dc_dc_ilim(struct ad5758_state *st, unsigned int ilim)
{
int ret;
ret = ad5758_spi_write_mask(st, AD5758_DCDC_CONFIG2,
AD5758_DCDC_CONFIG2_ILIMIT_MSK,
AD5758_DCDC_CONFIG2_ILIMIT_MODE(ilim));
if (ret < 0)
return ret;
/*
* Poll the BUSY_3WI bit in the DCDC_CONFIG2 register until it is 0.
* This allows the 3-wire interface communication to complete.
*/
return ad5758_wait_for_task_complete(st, AD5758_DCDC_CONFIG2,
AD5758_DCDC_CONFIG2_BUSY_3WI_MSK);
}
static int ad5758_slew_rate_set(struct ad5758_state *st,
unsigned int sr_clk_idx,
unsigned int sr_step_idx)
{
unsigned int mode;
unsigned long int mask;
int ret;
mask = AD5758_DAC_CONFIG_SR_EN_MSK |
AD5758_DAC_CONFIG_SR_CLOCK_MSK |
AD5758_DAC_CONFIG_SR_STEP_MSK;
mode = AD5758_DAC_CONFIG_SR_EN_MODE(1) |
AD5758_DAC_CONFIG_SR_STEP_MODE(sr_step_idx) |
AD5758_DAC_CONFIG_SR_CLOCK_MODE(sr_clk_idx);
ret = ad5758_spi_write_mask(st, AD5758_DAC_CONFIG, mask, mode);
if (ret < 0)
return ret;
/* Wait to allow time for the internal calibrations to complete */
return ad5758_wait_for_task_complete(st, AD5758_DIGITAL_DIAG_RESULTS,
AD5758_CAL_MEM_UNREFRESHED_MSK);
}
static int ad5758_slew_rate_config(struct ad5758_state *st)
{
unsigned int sr_clk_idx, sr_step_idx;
int i, res;
s64 diff_new, diff_old;
u64 sr_step, calc_slew_time;
sr_clk_idx = 0;
sr_step_idx = 0;
diff_old = S64_MAX;
/*
* The slew time can be determined by using the formula:
* Slew Time = (Full Scale Out / (Step Size x Update Clk Freq))
* where Slew time is expressed in microseconds
* Given the desired slew time, the following algorithm determines the
* best match for the step size and the update clock frequency.
*/
for (i = 0; i < ARRAY_SIZE(ad5758_sr_clk); i++) {
/*
* Go through each valid update clock freq and determine a raw
* value for the step size by using the formula:
* Step Size = Full Scale Out / (Update Clk Freq * Slew Time)
*/
sr_step = AD5758_FULL_SCALE_MICRO;
do_div(sr_step, ad5758_sr_clk[i]);
do_div(sr_step, st->slew_time);
/*
* After a raw value for step size was determined, find the
* closest valid match
*/
res = ad5758_find_closest_match(ad5758_sr_step,
ARRAY_SIZE(ad5758_sr_step),
sr_step);
/* Calculate the slew time */
calc_slew_time = AD5758_FULL_SCALE_MICRO;
do_div(calc_slew_time, ad5758_sr_step[res]);
do_div(calc_slew_time, ad5758_sr_clk[i]);
/*
* Determine with how many microseconds the calculated slew time
* is different from the desired slew time and store the diff
* for the next iteration
*/
diff_new = abs(st->slew_time - calc_slew_time);
if (diff_new < diff_old) {
diff_old = diff_new;
sr_clk_idx = i;
sr_step_idx = res;
}
}
return ad5758_slew_rate_set(st, sr_clk_idx, sr_step_idx);
}
static int ad5758_set_out_range(struct ad5758_state *st, int range)
{
int ret;
ret = ad5758_spi_write_mask(st, AD5758_DAC_CONFIG,
AD5758_DAC_CONFIG_RANGE_MSK,
AD5758_DAC_CONFIG_RANGE_MODE(range));
if (ret < 0)
return ret;
/* Wait to allow time for the internal calibrations to complete */
return ad5758_wait_for_task_complete(st, AD5758_DIGITAL_DIAG_RESULTS,
AD5758_CAL_MEM_UNREFRESHED_MSK);
}
static int ad5758_fault_prot_switch_en(struct ad5758_state *st, bool enable)
{
int ret;
ret = ad5758_spi_write_mask(st, AD5758_DCDC_CONFIG1,
AD5758_DCDC_CONFIG1_PROT_SW_EN_MSK,
AD5758_DCDC_CONFIG1_PROT_SW_EN_MODE(enable));
if (ret < 0)
return ret;
/*
* Poll the BUSY_3WI bit in the DCDC_CONFIG2 register until it is 0.
* This allows the 3-wire interface communication to complete.
*/
return ad5758_wait_for_task_complete(st, AD5758_DCDC_CONFIG2,
AD5758_DCDC_CONFIG2_BUSY_3WI_MSK);
}
static int ad5758_internal_buffers_en(struct ad5758_state *st, bool enable)
{
int ret;
ret = ad5758_spi_write_mask(st, AD5758_DAC_CONFIG,
AD5758_DAC_CONFIG_INT_EN_MSK,
AD5758_DAC_CONFIG_INT_EN_MODE(enable));
if (ret < 0)
return ret;
/* Wait to allow time for the internal calibrations to complete */
return ad5758_wait_for_task_complete(st, AD5758_DIGITAL_DIAG_RESULTS,
AD5758_CAL_MEM_UNREFRESHED_MSK);
}
static int ad5758_reg_access(struct iio_dev *indio_dev,
unsigned int reg,
unsigned int writeval,
unsigned int *readval)
{
struct ad5758_state *st = iio_priv(indio_dev);
int ret;
mutex_lock(&st->lock);
if (readval) {
ret = ad5758_spi_reg_read(st, reg);
if (ret < 0) {
mutex_unlock(&st->lock);
return ret;
}
*readval = ret;
ret = 0;
} else {
ret = ad5758_spi_reg_write(st, reg, writeval);
}
mutex_unlock(&st->lock);
return ret;
}
static int ad5758_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long info)
{
struct ad5758_state *st = iio_priv(indio_dev);
int max, min, ret;
switch (info) {
case IIO_CHAN_INFO_RAW:
mutex_lock(&st->lock);
ret = ad5758_spi_reg_read(st, AD5758_DAC_INPUT);
mutex_unlock(&st->lock);
if (ret < 0)
return ret;
*val = ret;
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
min = st->out_range.min;
max = st->out_range.max;
*val = (max - min) / 1000;
*val2 = 16;
return IIO_VAL_FRACTIONAL_LOG2;
case IIO_CHAN_INFO_OFFSET:
min = st->out_range.min;
max = st->out_range.max;
*val = ((min * (1 << 16)) / (max - min)) / 1000;
return IIO_VAL_INT;
default:
return -EINVAL;
}
}
static int ad5758_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int val, int val2, long info)
{
struct ad5758_state *st = iio_priv(indio_dev);
int ret;
switch (info) {
case IIO_CHAN_INFO_RAW:
mutex_lock(&st->lock);
ret = ad5758_spi_reg_write(st, AD5758_DAC_INPUT, val);
mutex_unlock(&st->lock);
return ret;
default:
return -EINVAL;
}
}
static ssize_t ad5758_read_powerdown(struct iio_dev *indio_dev,
uintptr_t priv,
const struct iio_chan_spec *chan,
char *buf)
{
struct ad5758_state *st = iio_priv(indio_dev);
return sprintf(buf, "%d\n", st->pwr_down);
}
static ssize_t ad5758_write_powerdown(struct iio_dev *indio_dev,
uintptr_t priv,
struct iio_chan_spec const *chan,
const char *buf, size_t len)
{
struct ad5758_state *st = iio_priv(indio_dev);
bool pwr_down;
unsigned int dcdc_config1_mode, dc_dc_mode, dac_config_mode, val;
unsigned long int dcdc_config1_msk, dac_config_msk;
int ret;
ret = kstrtobool(buf, &pwr_down);
if (ret)
return ret;
mutex_lock(&st->lock);
if (pwr_down) {
dc_dc_mode = AD5758_DCDC_MODE_POWER_OFF;
val = 0;
} else {
dc_dc_mode = st->dc_dc_mode;
val = 1;
}
dcdc_config1_mode = AD5758_DCDC_CONFIG1_DCDC_MODE_MODE(dc_dc_mode) |
AD5758_DCDC_CONFIG1_PROT_SW_EN_MODE(val);
dcdc_config1_msk = AD5758_DCDC_CONFIG1_DCDC_MODE_MSK |
AD5758_DCDC_CONFIG1_PROT_SW_EN_MSK;
ret = ad5758_spi_write_mask(st, AD5758_DCDC_CONFIG1,
dcdc_config1_msk,
dcdc_config1_mode);
if (ret < 0)
goto err_unlock;
dac_config_mode = AD5758_DAC_CONFIG_OUT_EN_MODE(val) |
AD5758_DAC_CONFIG_INT_EN_MODE(val);
dac_config_msk = AD5758_DAC_CONFIG_OUT_EN_MSK |
AD5758_DAC_CONFIG_INT_EN_MSK;
ret = ad5758_spi_write_mask(st, AD5758_DAC_CONFIG,
dac_config_msk,
dac_config_mode);
if (ret < 0)
goto err_unlock;
st->pwr_down = pwr_down;
err_unlock:
mutex_unlock(&st->lock);
return ret ? ret : len;
}
static const struct iio_info ad5758_info = {
.read_raw = ad5758_read_raw,
.write_raw = ad5758_write_raw,
.debugfs_reg_access = &ad5758_reg_access,
};
static const struct iio_chan_spec_ext_info ad5758_ext_info[] = {
{
.name = "powerdown",
.read = ad5758_read_powerdown,
.write = ad5758_write_powerdown,
.shared = IIO_SHARED_BY_TYPE,
},
{ }
};
#define AD5758_DAC_CHAN(_chan_type) { \
.type = (_chan_type), \
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_RAW) | \
BIT(IIO_CHAN_INFO_SCALE) | \
BIT(IIO_CHAN_INFO_OFFSET), \
.indexed = 1, \
.output = 1, \
.ext_info = ad5758_ext_info, \
}
static const struct iio_chan_spec ad5758_voltage_ch[] = {
AD5758_DAC_CHAN(IIO_VOLTAGE)
};
static const struct iio_chan_spec ad5758_current_ch[] = {
AD5758_DAC_CHAN(IIO_CURRENT)
};
static bool ad5758_is_valid_mode(enum ad5758_dc_dc_mode mode)
{
switch (mode) {
case AD5758_DCDC_MODE_DPC_CURRENT:
case AD5758_DCDC_MODE_DPC_VOLTAGE:
case AD5758_DCDC_MODE_PPC_CURRENT:
return true;
default:
return false;
}
}
static int ad5758_crc_disable(struct ad5758_state *st)
{
unsigned int mask;
mask = (AD5758_WR_FLAG_MSK(AD5758_DIGITAL_DIAG_CONFIG) << 24) | 0x5C3A;
st->d32[0] = cpu_to_be32(mask);
return spi_write(st->spi, &st->d32[0], 4);
}
static int ad5758_find_out_range(struct ad5758_state *st,
const struct ad5758_range *range,
unsigned int size,
int min, int max)
{
int i;
for (i = 0; i < size; i++) {
if ((min == range[i].min) && (max == range[i].max)) {
st->out_range.reg = range[i].reg;
st->out_range.min = range[i].min;
st->out_range.max = range[i].max;
return 0;
}
}
return -EINVAL;
}
static int ad5758_parse_dt(struct ad5758_state *st)
{
unsigned int tmp, tmparray[2], size;
const struct ad5758_range *range;
int *index, ret;
st->dc_dc_ilim = 0;
ret = device_property_read_u32(&st->spi->dev,
"adi,dc-dc-ilim-microamp", &tmp);
if (ret) {
dev_dbg(&st->spi->dev,
"Missing \"dc-dc-ilim-microamp\" property\n");
} else {
index = bsearch(&tmp, ad5758_dc_dc_ilim,
ARRAY_SIZE(ad5758_dc_dc_ilim),
sizeof(int), cmpfunc);
if (!index)
dev_dbg(&st->spi->dev, "dc-dc-ilim out of range\n");
else
st->dc_dc_ilim = index - ad5758_dc_dc_ilim;
}
ret = device_property_read_u32(&st->spi->dev, "adi,dc-dc-mode",
&st->dc_dc_mode);
if (ret) {
dev_err(&st->spi->dev, "Missing \"dc-dc-mode\" property\n");
return ret;
}
if (!ad5758_is_valid_mode(st->dc_dc_mode))
return -EINVAL;
if (st->dc_dc_mode == AD5758_DCDC_MODE_DPC_VOLTAGE) {
ret = device_property_read_u32_array(&st->spi->dev,
"adi,range-microvolt",
tmparray, 2);
if (ret) {
dev_err(&st->spi->dev,
"Missing \"range-microvolt\" property\n");
return ret;
}
range = ad5758_voltage_range;
size = ARRAY_SIZE(ad5758_voltage_range);
} else {
ret = device_property_read_u32_array(&st->spi->dev,
"adi,range-microamp",
tmparray, 2);
if (ret) {
dev_err(&st->spi->dev,
"Missing \"range-microamp\" property\n");
return ret;
}
range = ad5758_current_range;
size = ARRAY_SIZE(ad5758_current_range);
}
ret = ad5758_find_out_range(st, range, size, tmparray[0], tmparray[1]);
if (ret) {
dev_err(&st->spi->dev, "range invalid\n");
return ret;
}
ret = device_property_read_u32(&st->spi->dev, "adi,slew-time-us", &tmp);
if (ret) {
dev_dbg(&st->spi->dev, "Missing \"slew-time-us\" property\n");
st->slew_time = 0;
} else {
st->slew_time = tmp;
}
return 0;
}
static int ad5758_init(struct ad5758_state *st)
{
int regval, ret;
/* Disable CRC checks */
ret = ad5758_crc_disable(st);
if (ret < 0)
return ret;
/* Perform a software reset */
ret = ad5758_soft_reset(st);
if (ret < 0)
return ret;
/* Disable CRC checks */
ret = ad5758_crc_disable(st);
if (ret < 0)
return ret;
/* Perform a calibration memory refresh */
ret = ad5758_calib_mem_refresh(st);
if (ret < 0)
return ret;
regval = ad5758_spi_reg_read(st, AD5758_DIGITAL_DIAG_RESULTS);
if (regval < 0)
return regval;
/* Clear all the error flags */
ret = ad5758_spi_reg_write(st, AD5758_DIGITAL_DIAG_RESULTS, regval);
if (ret < 0)
return ret;
/* Set the dc-to-dc current limit */
ret = ad5758_set_dc_dc_ilim(st, st->dc_dc_ilim);
if (ret < 0)
return ret;
/* Configure the dc-to-dc controller mode */
ret = ad5758_set_dc_dc_conv_mode(st, st->dc_dc_mode);
if (ret < 0)
return ret;
/* Configure the output range */
ret = ad5758_set_out_range(st, st->out_range.reg);
if (ret < 0)
return ret;
/* Enable Slew Rate Control, set the slew rate clock and step */
if (st->slew_time) {
ret = ad5758_slew_rate_config(st);
if (ret < 0)
return ret;
}
/* Enable the VIOUT fault protection switch (FPS is closed) */
ret = ad5758_fault_prot_switch_en(st, 1);
if (ret < 0)
return ret;
/* Power up the DAC and internal (INT) amplifiers */
ret = ad5758_internal_buffers_en(st, 1);
if (ret < 0)
return ret;
/* Enable VIOUT */
return ad5758_spi_write_mask(st, AD5758_DAC_CONFIG,
AD5758_DAC_CONFIG_OUT_EN_MSK,
AD5758_DAC_CONFIG_OUT_EN_MODE(1));
}
static int ad5758_probe(struct spi_device *spi)
{
struct ad5758_state *st;
struct iio_dev *indio_dev;
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;
mutex_init(&st->lock);
indio_dev->dev.parent = &spi->dev;
indio_dev->name = spi_get_device_id(spi)->name;
indio_dev->info = &ad5758_info;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->num_channels = 1;
ret = ad5758_parse_dt(st);
if (ret < 0)
return ret;
if (st->dc_dc_mode == AD5758_DCDC_MODE_DPC_VOLTAGE)
indio_dev->channels = ad5758_voltage_ch;
else
indio_dev->channels = ad5758_current_ch;
ret = ad5758_init(st);
if (ret < 0) {
dev_err(&spi->dev, "AD5758 init failed\n");
return ret;
}
return devm_iio_device_register(&st->spi->dev, indio_dev);
}
static const struct spi_device_id ad5758_id[] = {
{ "ad5758", 0 },
{}
};
MODULE_DEVICE_TABLE(spi, ad5758_id);
static struct spi_driver ad5758_driver = {
.driver = {
.name = KBUILD_MODNAME,
},
.probe = ad5758_probe,
.id_table = ad5758_id,
};
module_spi_driver(ad5758_driver);
MODULE_AUTHOR("Stefan Popa <stefan.popa@analog.com>");
MODULE_DESCRIPTION("Analog Devices AD5758 DAC");
MODULE_LICENSE("GPL v2");