blob: 69c586525d2158e918d2feb6308eabd57c6bf689 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2021 Analog Devices, Inc.
* Author: Cosmin Tanislav <cosmin.tanislav@analog.com>
*/
#include <linux/unaligned.h>
#include <linux/bitfield.h>
#include <linux/crc8.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/gpio/driver.h>
#include <linux/iio/buffer.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/trigger.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/triggered_buffer.h>
#include <linux/interrupt.h>
#include <linux/mod_devicetable.h>
#include <linux/property.h>
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>
#include <linux/spi/spi.h>
#include <dt-bindings/iio/addac/adi,ad74413r.h>
#define AD74413R_CRC_POLYNOMIAL 0x7
DECLARE_CRC8_TABLE(ad74413r_crc8_table);
#define AD74413R_CHANNEL_MAX 4
#define AD74413R_FRAME_SIZE 4
struct ad74413r_chip_info {
const char *name;
bool hart_support;
};
struct ad74413r_channel_config {
u32 func;
u32 drive_strength;
bool gpo_comparator;
bool initialized;
};
struct ad74413r_channels {
struct iio_chan_spec *channels;
unsigned int num_channels;
};
struct ad74413r_state {
struct ad74413r_channel_config channel_configs[AD74413R_CHANNEL_MAX];
unsigned int gpo_gpio_offsets[AD74413R_CHANNEL_MAX];
unsigned int comp_gpio_offsets[AD74413R_CHANNEL_MAX];
struct gpio_chip gpo_gpiochip;
struct gpio_chip comp_gpiochip;
struct completion adc_data_completion;
unsigned int num_gpo_gpios;
unsigned int num_comparator_gpios;
u32 sense_resistor_ohms;
/*
* Synchronize consecutive operations when doing a one-shot
* conversion and when updating the ADC samples SPI message.
*/
struct mutex lock;
const struct ad74413r_chip_info *chip_info;
struct spi_device *spi;
struct regulator *refin_reg;
struct regmap *regmap;
struct device *dev;
struct iio_trigger *trig;
struct gpio_desc *reset_gpio;
size_t adc_active_channels;
struct spi_message adc_samples_msg;
struct spi_transfer adc_samples_xfer[AD74413R_CHANNEL_MAX + 1];
/*
* DMA (thus cache coherency maintenance) may require the
* transfer buffers to live in their own cache lines.
*/
struct {
u8 rx_buf[AD74413R_FRAME_SIZE * AD74413R_CHANNEL_MAX];
s64 timestamp;
} adc_samples_buf __aligned(IIO_DMA_MINALIGN);
u8 adc_samples_tx_buf[AD74413R_FRAME_SIZE * AD74413R_CHANNEL_MAX];
u8 reg_tx_buf[AD74413R_FRAME_SIZE];
u8 reg_rx_buf[AD74413R_FRAME_SIZE];
};
#define AD74413R_REG_NOP 0x00
#define AD74413R_REG_CH_FUNC_SETUP_X(x) (0x01 + (x))
#define AD74413R_CH_FUNC_SETUP_MASK GENMASK(3, 0)
#define AD74413R_REG_ADC_CONFIG_X(x) (0x05 + (x))
#define AD74413R_ADC_CONFIG_RANGE_MASK GENMASK(7, 5)
#define AD74413R_ADC_CONFIG_REJECTION_MASK GENMASK(4, 3)
#define AD74413R_ADC_CONFIG_CH_200K_TO_GND BIT(2)
#define AD74413R_ADC_RANGE_10V 0b000
#define AD74413R_ADC_RANGE_2P5V_EXT_POW 0b001
#define AD74413R_ADC_RANGE_2P5V_INT_POW 0b010
#define AD74413R_ADC_RANGE_5V_BI_DIR 0b011
#define AD74413R_ADC_REJECTION_50_60 0b00
#define AD74413R_ADC_REJECTION_NONE 0b01
#define AD74413R_ADC_REJECTION_50_60_HART 0b10
#define AD74413R_ADC_REJECTION_HART 0b11
#define AD74413R_REG_DIN_CONFIG_X(x) (0x09 + (x))
#define AD74413R_DIN_DEBOUNCE_MASK GENMASK(4, 0)
#define AD74413R_DIN_DEBOUNCE_LEN BIT(5)
#define AD74413R_DIN_SINK_MASK GENMASK(9, 6)
#define AD74413R_REG_DAC_CODE_X(x) (0x16 + (x))
#define AD74413R_DAC_CODE_MAX GENMASK(12, 0)
#define AD74413R_DAC_VOLTAGE_MAX 11000
#define AD74413R_REG_GPO_PAR_DATA 0x0d
#define AD74413R_REG_GPO_CONFIG_X(x) (0x0e + (x))
#define AD74413R_GPO_CONFIG_DATA_MASK BIT(3)
#define AD74413R_GPO_CONFIG_SELECT_MASK GENMASK(2, 0)
#define AD74413R_GPO_CONFIG_100K_PULL_DOWN 0b000
#define AD74413R_GPO_CONFIG_LOGIC 0b001
#define AD74413R_GPO_CONFIG_LOGIC_PARALLEL 0b010
#define AD74413R_GPO_CONFIG_COMPARATOR 0b011
#define AD74413R_GPO_CONFIG_HIGH_IMPEDANCE 0b100
#define AD74413R_REG_ADC_CONV_CTRL 0x23
#define AD74413R_CONV_SEQ_MASK GENMASK(9, 8)
#define AD74413R_CONV_SEQ_ON 0b00
#define AD74413R_CONV_SEQ_SINGLE 0b01
#define AD74413R_CONV_SEQ_CONTINUOUS 0b10
#define AD74413R_CONV_SEQ_OFF 0b11
#define AD74413R_CH_EN_MASK(x) BIT(x)
#define AD74413R_REG_DIN_COMP_OUT 0x25
#define AD74413R_REG_ADC_RESULT_X(x) (0x26 + (x))
#define AD74413R_ADC_RESULT_MAX GENMASK(15, 0)
#define AD74413R_REG_READ_SELECT 0x41
#define AD74413R_REG_CMD_KEY 0x44
#define AD74413R_CMD_KEY_LDAC 0x953a
#define AD74413R_CMD_KEY_RESET1 0x15fa
#define AD74413R_CMD_KEY_RESET2 0xaf51
static const int ad74413r_adc_sampling_rates[] = {
20, 4800,
};
static const int ad74413r_adc_sampling_rates_hart[] = {
10, 20, 1200, 4800,
};
static int ad74413r_crc(u8 *buf)
{
return crc8(ad74413r_crc8_table, buf, 3, 0);
}
static void ad74413r_format_reg_write(u8 reg, u16 val, u8 *buf)
{
buf[0] = reg;
put_unaligned_be16(val, &buf[1]);
buf[3] = ad74413r_crc(buf);
}
static int ad74413r_reg_write(void *context, unsigned int reg, unsigned int val)
{
struct ad74413r_state *st = context;
ad74413r_format_reg_write(reg, val, st->reg_tx_buf);
return spi_write(st->spi, st->reg_tx_buf, AD74413R_FRAME_SIZE);
}
static int ad74413r_crc_check(struct ad74413r_state *st, u8 *buf)
{
u8 expected_crc = ad74413r_crc(buf);
if (buf[3] != expected_crc) {
dev_err(st->dev, "Bad CRC %02x for %02x%02x%02x\n",
buf[3], buf[0], buf[1], buf[2]);
return -EINVAL;
}
return 0;
}
static int ad74413r_reg_read(void *context, unsigned int reg, unsigned int *val)
{
struct ad74413r_state *st = context;
struct spi_transfer reg_read_xfer[] = {
{
.tx_buf = st->reg_tx_buf,
.len = AD74413R_FRAME_SIZE,
.cs_change = 1,
},
{
.rx_buf = st->reg_rx_buf,
.len = AD74413R_FRAME_SIZE,
},
};
int ret;
ad74413r_format_reg_write(AD74413R_REG_READ_SELECT, reg,
st->reg_tx_buf);
ret = spi_sync_transfer(st->spi, reg_read_xfer,
ARRAY_SIZE(reg_read_xfer));
if (ret)
return ret;
ret = ad74413r_crc_check(st, st->reg_rx_buf);
if (ret)
return ret;
*val = get_unaligned_be16(&st->reg_rx_buf[1]);
return 0;
}
static const struct regmap_config ad74413r_regmap_config = {
.reg_bits = 8,
.val_bits = 16,
.reg_read = ad74413r_reg_read,
.reg_write = ad74413r_reg_write,
};
static int ad74413r_set_gpo_config(struct ad74413r_state *st,
unsigned int offset, u8 mode)
{
return regmap_update_bits(st->regmap, AD74413R_REG_GPO_CONFIG_X(offset),
AD74413R_GPO_CONFIG_SELECT_MASK, mode);
}
static const unsigned int ad74413r_debounce_map[AD74413R_DIN_DEBOUNCE_LEN] = {
0, 13, 18, 24, 32, 42, 56, 75,
100, 130, 180, 240, 320, 420, 560, 750,
1000, 1300, 1800, 2400, 3200, 4200, 5600, 7500,
10000, 13000, 18000, 24000, 32000, 42000, 56000, 75000,
};
static int ad74413r_set_comp_debounce(struct ad74413r_state *st,
unsigned int offset,
unsigned int debounce)
{
unsigned int val = AD74413R_DIN_DEBOUNCE_LEN - 1;
unsigned int i;
for (i = 0; i < AD74413R_DIN_DEBOUNCE_LEN; i++)
if (debounce <= ad74413r_debounce_map[i]) {
val = i;
break;
}
return regmap_update_bits(st->regmap,
AD74413R_REG_DIN_CONFIG_X(offset),
AD74413R_DIN_DEBOUNCE_MASK,
val);
}
static int ad74413r_set_comp_drive_strength(struct ad74413r_state *st,
unsigned int offset,
unsigned int strength)
{
strength = min(strength, 1800U);
return regmap_update_bits(st->regmap, AD74413R_REG_DIN_CONFIG_X(offset),
AD74413R_DIN_SINK_MASK,
FIELD_PREP(AD74413R_DIN_SINK_MASK, strength / 120));
}
static void ad74413r_gpio_set(struct gpio_chip *chip,
unsigned int offset, int val)
{
struct ad74413r_state *st = gpiochip_get_data(chip);
unsigned int real_offset = st->gpo_gpio_offsets[offset];
int ret;
ret = ad74413r_set_gpo_config(st, real_offset,
AD74413R_GPO_CONFIG_LOGIC);
if (ret)
return;
regmap_update_bits(st->regmap, AD74413R_REG_GPO_CONFIG_X(real_offset),
AD74413R_GPO_CONFIG_DATA_MASK,
val ? AD74413R_GPO_CONFIG_DATA_MASK : 0);
}
static void ad74413r_gpio_set_multiple(struct gpio_chip *chip,
unsigned long *mask,
unsigned long *bits)
{
struct ad74413r_state *st = gpiochip_get_data(chip);
unsigned long real_mask = 0;
unsigned long real_bits = 0;
unsigned int offset;
int ret;
for_each_set_bit(offset, mask, chip->ngpio) {
unsigned int real_offset = st->gpo_gpio_offsets[offset];
ret = ad74413r_set_gpo_config(st, real_offset,
AD74413R_GPO_CONFIG_LOGIC_PARALLEL);
if (ret)
return;
real_mask |= BIT(real_offset);
if (*bits & offset)
real_bits |= BIT(real_offset);
}
regmap_update_bits(st->regmap, AD74413R_REG_GPO_PAR_DATA,
real_mask, real_bits);
}
static int ad74413r_gpio_get(struct gpio_chip *chip, unsigned int offset)
{
struct ad74413r_state *st = gpiochip_get_data(chip);
unsigned int real_offset = st->comp_gpio_offsets[offset];
unsigned int status;
int ret;
ret = regmap_read(st->regmap, AD74413R_REG_DIN_COMP_OUT, &status);
if (ret)
return ret;
status &= BIT(real_offset);
return status ? 1 : 0;
}
static int ad74413r_gpio_get_multiple(struct gpio_chip *chip,
unsigned long *mask,
unsigned long *bits)
{
struct ad74413r_state *st = gpiochip_get_data(chip);
unsigned int offset;
unsigned int val;
int ret;
ret = regmap_read(st->regmap, AD74413R_REG_DIN_COMP_OUT, &val);
if (ret)
return ret;
for_each_set_bit(offset, mask, chip->ngpio) {
unsigned int real_offset = st->comp_gpio_offsets[offset];
__assign_bit(offset, bits, val & BIT(real_offset));
}
return ret;
}
static int ad74413r_gpio_get_gpo_direction(struct gpio_chip *chip,
unsigned int offset)
{
return GPIO_LINE_DIRECTION_OUT;
}
static int ad74413r_gpio_get_comp_direction(struct gpio_chip *chip,
unsigned int offset)
{
return GPIO_LINE_DIRECTION_IN;
}
static int ad74413r_gpio_set_gpo_config(struct gpio_chip *chip,
unsigned int offset,
unsigned long config)
{
struct ad74413r_state *st = gpiochip_get_data(chip);
unsigned int real_offset = st->gpo_gpio_offsets[offset];
switch (pinconf_to_config_param(config)) {
case PIN_CONFIG_BIAS_PULL_DOWN:
return ad74413r_set_gpo_config(st, real_offset,
AD74413R_GPO_CONFIG_100K_PULL_DOWN);
case PIN_CONFIG_BIAS_HIGH_IMPEDANCE:
return ad74413r_set_gpo_config(st, real_offset,
AD74413R_GPO_CONFIG_HIGH_IMPEDANCE);
default:
return -ENOTSUPP;
}
}
static int ad74413r_gpio_set_comp_config(struct gpio_chip *chip,
unsigned int offset,
unsigned long config)
{
struct ad74413r_state *st = gpiochip_get_data(chip);
unsigned int real_offset = st->comp_gpio_offsets[offset];
switch (pinconf_to_config_param(config)) {
case PIN_CONFIG_INPUT_DEBOUNCE:
return ad74413r_set_comp_debounce(st, real_offset,
pinconf_to_config_argument(config));
default:
return -ENOTSUPP;
}
}
static int ad74413r_reset(struct ad74413r_state *st)
{
int ret;
if (st->reset_gpio) {
gpiod_set_value_cansleep(st->reset_gpio, 1);
fsleep(50);
gpiod_set_value_cansleep(st->reset_gpio, 0);
return 0;
}
ret = regmap_write(st->regmap, AD74413R_REG_CMD_KEY,
AD74413R_CMD_KEY_RESET1);
if (ret)
return ret;
return regmap_write(st->regmap, AD74413R_REG_CMD_KEY,
AD74413R_CMD_KEY_RESET2);
}
static int ad74413r_set_channel_dac_code(struct ad74413r_state *st,
unsigned int channel, int dac_code)
{
struct reg_sequence reg_seq[2] = {
{ AD74413R_REG_DAC_CODE_X(channel), dac_code },
{ AD74413R_REG_CMD_KEY, AD74413R_CMD_KEY_LDAC },
};
return regmap_multi_reg_write(st->regmap, reg_seq, 2);
}
static int ad74413r_set_channel_function(struct ad74413r_state *st,
unsigned int channel, u8 func)
{
int ret;
ret = regmap_update_bits(st->regmap,
AD74413R_REG_CH_FUNC_SETUP_X(channel),
AD74413R_CH_FUNC_SETUP_MASK,
CH_FUNC_HIGH_IMPEDANCE);
if (ret)
return ret;
/* Set DAC code to 0 prior to changing channel function */
ret = ad74413r_set_channel_dac_code(st, channel, 0);
if (ret)
return ret;
/* Delay required before transition to new desired mode */
usleep_range(130, 150);
ret = regmap_update_bits(st->regmap,
AD74413R_REG_CH_FUNC_SETUP_X(channel),
AD74413R_CH_FUNC_SETUP_MASK, func);
if (ret)
return ret;
/* Delay required before updating the new DAC code */
usleep_range(150, 170);
if (func == CH_FUNC_CURRENT_INPUT_LOOP_POWER)
ret = regmap_set_bits(st->regmap,
AD74413R_REG_ADC_CONFIG_X(channel),
AD74413R_ADC_CONFIG_CH_200K_TO_GND);
return ret;
}
static int ad74413r_set_adc_conv_seq(struct ad74413r_state *st,
unsigned int status)
{
int ret;
/*
* These bits do not clear when a conversion completes.
* To enable a subsequent conversion, repeat the write.
*/
ret = regmap_write_bits(st->regmap, AD74413R_REG_ADC_CONV_CTRL,
AD74413R_CONV_SEQ_MASK,
FIELD_PREP(AD74413R_CONV_SEQ_MASK, status));
if (ret)
return ret;
/*
* Wait 100us before starting conversions.
*/
usleep_range(100, 120);
return 0;
}
static int ad74413r_set_adc_channel_enable(struct ad74413r_state *st,
unsigned int channel,
bool status)
{
return regmap_update_bits(st->regmap, AD74413R_REG_ADC_CONV_CTRL,
AD74413R_CH_EN_MASK(channel),
status ? AD74413R_CH_EN_MASK(channel) : 0);
}
static int ad74413r_get_adc_range(struct ad74413r_state *st,
unsigned int channel,
unsigned int *val)
{
int ret;
ret = regmap_read(st->regmap, AD74413R_REG_ADC_CONFIG_X(channel), val);
if (ret)
return ret;
*val = FIELD_GET(AD74413R_ADC_CONFIG_RANGE_MASK, *val);
return 0;
}
static int ad74413r_get_adc_rejection(struct ad74413r_state *st,
unsigned int channel,
unsigned int *val)
{
int ret;
ret = regmap_read(st->regmap, AD74413R_REG_ADC_CONFIG_X(channel), val);
if (ret)
return ret;
*val = FIELD_GET(AD74413R_ADC_CONFIG_REJECTION_MASK, *val);
return 0;
}
static int ad74413r_set_adc_rejection(struct ad74413r_state *st,
unsigned int channel,
unsigned int val)
{
return regmap_update_bits(st->regmap,
AD74413R_REG_ADC_CONFIG_X(channel),
AD74413R_ADC_CONFIG_REJECTION_MASK,
FIELD_PREP(AD74413R_ADC_CONFIG_REJECTION_MASK,
val));
}
static int ad74413r_rejection_to_rate(struct ad74413r_state *st,
unsigned int rej, int *val)
{
switch (rej) {
case AD74413R_ADC_REJECTION_50_60:
*val = 20;
return 0;
case AD74413R_ADC_REJECTION_NONE:
*val = 4800;
return 0;
case AD74413R_ADC_REJECTION_50_60_HART:
*val = 10;
return 0;
case AD74413R_ADC_REJECTION_HART:
*val = 1200;
return 0;
default:
dev_err(st->dev, "ADC rejection invalid\n");
return -EINVAL;
}
}
static int ad74413r_rate_to_rejection(struct ad74413r_state *st,
int rate, unsigned int *val)
{
switch (rate) {
case 20:
*val = AD74413R_ADC_REJECTION_50_60;
return 0;
case 4800:
*val = AD74413R_ADC_REJECTION_NONE;
return 0;
case 10:
*val = AD74413R_ADC_REJECTION_50_60_HART;
return 0;
case 1200:
*val = AD74413R_ADC_REJECTION_HART;
return 0;
default:
dev_err(st->dev, "ADC rate invalid\n");
return -EINVAL;
}
}
static int ad74413r_range_to_voltage_range(struct ad74413r_state *st,
unsigned int range, int *val)
{
switch (range) {
case AD74413R_ADC_RANGE_10V:
*val = 10000;
return 0;
case AD74413R_ADC_RANGE_2P5V_EXT_POW:
case AD74413R_ADC_RANGE_2P5V_INT_POW:
*val = 2500;
return 0;
case AD74413R_ADC_RANGE_5V_BI_DIR:
*val = 5000;
return 0;
default:
dev_err(st->dev, "ADC range invalid\n");
return -EINVAL;
}
}
static int ad74413r_range_to_voltage_offset(struct ad74413r_state *st,
unsigned int range, int *val)
{
switch (range) {
case AD74413R_ADC_RANGE_10V:
case AD74413R_ADC_RANGE_2P5V_EXT_POW:
*val = 0;
return 0;
case AD74413R_ADC_RANGE_2P5V_INT_POW:
case AD74413R_ADC_RANGE_5V_BI_DIR:
*val = -2500;
return 0;
default:
dev_err(st->dev, "ADC range invalid\n");
return -EINVAL;
}
}
static int ad74413r_range_to_voltage_offset_raw(struct ad74413r_state *st,
unsigned int range, int *val)
{
switch (range) {
case AD74413R_ADC_RANGE_10V:
case AD74413R_ADC_RANGE_2P5V_EXT_POW:
*val = 0;
return 0;
case AD74413R_ADC_RANGE_2P5V_INT_POW:
*val = -((int)AD74413R_ADC_RESULT_MAX);
return 0;
case AD74413R_ADC_RANGE_5V_BI_DIR:
*val = -((int)AD74413R_ADC_RESULT_MAX / 2);
return 0;
default:
dev_err(st->dev, "ADC range invalid\n");
return -EINVAL;
}
}
static int ad74413r_get_output_voltage_scale(struct ad74413r_state *st,
int *val, int *val2)
{
*val = AD74413R_DAC_VOLTAGE_MAX;
*val2 = AD74413R_DAC_CODE_MAX;
return IIO_VAL_FRACTIONAL;
}
static int ad74413r_get_output_current_scale(struct ad74413r_state *st,
int *val, int *val2)
{
*val = regulator_get_voltage(st->refin_reg);
*val2 = st->sense_resistor_ohms * AD74413R_DAC_CODE_MAX * 1000;
return IIO_VAL_FRACTIONAL;
}
static int ad74413r_get_input_voltage_scale(struct ad74413r_state *st,
unsigned int channel,
int *val, int *val2)
{
unsigned int range;
int ret;
ret = ad74413r_get_adc_range(st, channel, &range);
if (ret)
return ret;
ret = ad74413r_range_to_voltage_range(st, range, val);
if (ret)
return ret;
*val2 = AD74413R_ADC_RESULT_MAX;
return IIO_VAL_FRACTIONAL;
}
static int ad74413r_get_input_voltage_offset(struct ad74413r_state *st,
unsigned int channel, int *val)
{
unsigned int range;
int ret;
ret = ad74413r_get_adc_range(st, channel, &range);
if (ret)
return ret;
ret = ad74413r_range_to_voltage_offset_raw(st, range, val);
if (ret)
return ret;
return IIO_VAL_INT;
}
static int ad74413r_get_input_current_scale(struct ad74413r_state *st,
unsigned int channel, int *val,
int *val2)
{
unsigned int range;
int ret;
ret = ad74413r_get_adc_range(st, channel, &range);
if (ret)
return ret;
ret = ad74413r_range_to_voltage_range(st, range, val);
if (ret)
return ret;
*val2 = AD74413R_ADC_RESULT_MAX * st->sense_resistor_ohms;
return IIO_VAL_FRACTIONAL;
}
static int ad74413r_get_input_current_offset(struct ad74413r_state *st,
unsigned int channel, int *val)
{
unsigned int range;
int voltage_range;
int voltage_offset;
int ret;
ret = ad74413r_get_adc_range(st, channel, &range);
if (ret)
return ret;
ret = ad74413r_range_to_voltage_range(st, range, &voltage_range);
if (ret)
return ret;
ret = ad74413r_range_to_voltage_offset(st, range, &voltage_offset);
if (ret)
return ret;
*val = voltage_offset * (int)AD74413R_ADC_RESULT_MAX / voltage_range;
return IIO_VAL_INT;
}
static int ad74413r_get_adc_rate(struct ad74413r_state *st,
unsigned int channel, int *val)
{
unsigned int rejection;
int ret;
ret = ad74413r_get_adc_rejection(st, channel, &rejection);
if (ret)
return ret;
ret = ad74413r_rejection_to_rate(st, rejection, val);
if (ret)
return ret;
return IIO_VAL_INT;
}
static int ad74413r_set_adc_rate(struct ad74413r_state *st,
unsigned int channel, int val)
{
unsigned int rejection;
int ret;
ret = ad74413r_rate_to_rejection(st, val, &rejection);
if (ret)
return ret;
return ad74413r_set_adc_rejection(st, channel, rejection);
}
static irqreturn_t ad74413r_trigger_handler(int irq, void *p)
{
struct iio_poll_func *pf = p;
struct iio_dev *indio_dev = pf->indio_dev;
struct ad74413r_state *st = iio_priv(indio_dev);
u8 *rx_buf = st->adc_samples_buf.rx_buf;
unsigned int i;
int ret;
ret = spi_sync(st->spi, &st->adc_samples_msg);
if (ret)
goto out;
for (i = 0; i < st->adc_active_channels; i++)
ad74413r_crc_check(st, &rx_buf[i * AD74413R_FRAME_SIZE]);
iio_push_to_buffers_with_timestamp(indio_dev, &st->adc_samples_buf,
iio_get_time_ns(indio_dev));
out:
iio_trigger_notify_done(indio_dev->trig);
return IRQ_HANDLED;
}
static irqreturn_t ad74413r_adc_data_interrupt(int irq, void *data)
{
struct iio_dev *indio_dev = data;
struct ad74413r_state *st = iio_priv(indio_dev);
if (iio_buffer_enabled(indio_dev))
iio_trigger_poll(st->trig);
else
complete(&st->adc_data_completion);
return IRQ_HANDLED;
}
static int _ad74413r_get_single_adc_result(struct ad74413r_state *st,
unsigned int channel, int *val)
{
unsigned int uval;
int ret;
reinit_completion(&st->adc_data_completion);
ret = ad74413r_set_adc_channel_enable(st, channel, true);
if (ret)
return ret;
ret = ad74413r_set_adc_conv_seq(st, AD74413R_CONV_SEQ_SINGLE);
if (ret)
return ret;
ret = wait_for_completion_timeout(&st->adc_data_completion,
msecs_to_jiffies(1000));
if (!ret) {
ret = -ETIMEDOUT;
return ret;
}
ret = regmap_read(st->regmap, AD74413R_REG_ADC_RESULT_X(channel),
&uval);
if (ret)
return ret;
ret = ad74413r_set_adc_conv_seq(st, AD74413R_CONV_SEQ_OFF);
if (ret)
return ret;
ret = ad74413r_set_adc_channel_enable(st, channel, false);
if (ret)
return ret;
*val = uval;
return IIO_VAL_INT;
}
static int ad74413r_get_single_adc_result(struct iio_dev *indio_dev,
unsigned int channel, int *val)
{
struct ad74413r_state *st = iio_priv(indio_dev);
int ret;
ret = iio_device_claim_direct_mode(indio_dev);
if (ret)
return ret;
mutex_lock(&st->lock);
ret = _ad74413r_get_single_adc_result(st, channel, val);
mutex_unlock(&st->lock);
iio_device_release_direct_mode(indio_dev);
return ret;
}
static void ad74413r_adc_to_resistance_result(int adc_result, int *val)
{
if (adc_result == AD74413R_ADC_RESULT_MAX)
adc_result = AD74413R_ADC_RESULT_MAX - 1;
*val = DIV_ROUND_CLOSEST(adc_result * 2100,
AD74413R_ADC_RESULT_MAX - adc_result);
}
static int ad74413r_update_scan_mode(struct iio_dev *indio_dev,
const unsigned long *active_scan_mask)
{
struct ad74413r_state *st = iio_priv(indio_dev);
struct spi_transfer *xfer = st->adc_samples_xfer;
u8 *rx_buf = st->adc_samples_buf.rx_buf;
u8 *tx_buf = st->adc_samples_tx_buf;
unsigned int channel;
int ret = -EINVAL;
mutex_lock(&st->lock);
spi_message_init(&st->adc_samples_msg);
st->adc_active_channels = 0;
for_each_clear_bit(channel, active_scan_mask, AD74413R_CHANNEL_MAX) {
ret = ad74413r_set_adc_channel_enable(st, channel, false);
if (ret)
goto out;
}
if (*active_scan_mask == 0)
goto out;
/*
* The read select register is used to select which register's value
* will be sent by the slave on the next SPI frame.
*
* Create an SPI message that, on each step, writes to the read select
* register to select the ADC result of the next enabled channel, and
* reads the ADC result of the previous enabled channel.
*
* Example:
* W: [WCH1] [WCH2] [WCH2] [WCH3] [ ]
* R: [ ] [RCH1] [RCH2] [RCH3] [RCH4]
*/
for_each_set_bit(channel, active_scan_mask, AD74413R_CHANNEL_MAX) {
ret = ad74413r_set_adc_channel_enable(st, channel, true);
if (ret)
goto out;
st->adc_active_channels++;
if (xfer == st->adc_samples_xfer)
xfer->rx_buf = NULL;
else
xfer->rx_buf = rx_buf;
xfer->tx_buf = tx_buf;
xfer->len = AD74413R_FRAME_SIZE;
xfer->cs_change = 1;
ad74413r_format_reg_write(AD74413R_REG_READ_SELECT,
AD74413R_REG_ADC_RESULT_X(channel),
tx_buf);
spi_message_add_tail(xfer, &st->adc_samples_msg);
tx_buf += AD74413R_FRAME_SIZE;
if (xfer != st->adc_samples_xfer)
rx_buf += AD74413R_FRAME_SIZE;
xfer++;
}
xfer->rx_buf = rx_buf;
xfer->tx_buf = NULL;
xfer->len = AD74413R_FRAME_SIZE;
xfer->cs_change = 0;
spi_message_add_tail(xfer, &st->adc_samples_msg);
out:
mutex_unlock(&st->lock);
return ret;
}
static int ad74413r_buffer_postenable(struct iio_dev *indio_dev)
{
struct ad74413r_state *st = iio_priv(indio_dev);
return ad74413r_set_adc_conv_seq(st, AD74413R_CONV_SEQ_CONTINUOUS);
}
static int ad74413r_buffer_predisable(struct iio_dev *indio_dev)
{
struct ad74413r_state *st = iio_priv(indio_dev);
return ad74413r_set_adc_conv_seq(st, AD74413R_CONV_SEQ_OFF);
}
static int ad74413r_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long info)
{
struct ad74413r_state *st = iio_priv(indio_dev);
switch (info) {
case IIO_CHAN_INFO_SCALE:
switch (chan->type) {
case IIO_VOLTAGE:
if (chan->output)
return ad74413r_get_output_voltage_scale(st,
val, val2);
else
return ad74413r_get_input_voltage_scale(st,
chan->channel, val, val2);
case IIO_CURRENT:
if (chan->output)
return ad74413r_get_output_current_scale(st,
val, val2);
else
return ad74413r_get_input_current_scale(st,
chan->channel, val, val2);
default:
return -EINVAL;
}
case IIO_CHAN_INFO_OFFSET:
switch (chan->type) {
case IIO_VOLTAGE:
return ad74413r_get_input_voltage_offset(st,
chan->channel, val);
case IIO_CURRENT:
return ad74413r_get_input_current_offset(st,
chan->channel, val);
default:
return -EINVAL;
}
case IIO_CHAN_INFO_RAW:
if (chan->output)
return -EINVAL;
return ad74413r_get_single_adc_result(indio_dev, chan->channel,
val);
case IIO_CHAN_INFO_PROCESSED: {
int ret;
ret = ad74413r_get_single_adc_result(indio_dev, chan->channel,
val);
if (ret < 0)
return ret;
ad74413r_adc_to_resistance_result(*val, val);
return ret;
}
case IIO_CHAN_INFO_SAMP_FREQ:
return ad74413r_get_adc_rate(st, chan->channel, val);
default:
return -EINVAL;
}
}
static int ad74413r_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int val, int val2, long info)
{
struct ad74413r_state *st = iio_priv(indio_dev);
switch (info) {
case IIO_CHAN_INFO_RAW:
if (!chan->output)
return -EINVAL;
if (val < 0 || val > AD74413R_DAC_CODE_MAX) {
dev_err(st->dev, "Invalid DAC code\n");
return -EINVAL;
}
return ad74413r_set_channel_dac_code(st, chan->channel, val);
case IIO_CHAN_INFO_SAMP_FREQ:
return ad74413r_set_adc_rate(st, chan->channel, val);
default:
return -EINVAL;
}
}
static int ad74413r_read_avail(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
const int **vals, int *type, int *length,
long info)
{
struct ad74413r_state *st = iio_priv(indio_dev);
switch (info) {
case IIO_CHAN_INFO_SAMP_FREQ:
if (st->chip_info->hart_support) {
*vals = ad74413r_adc_sampling_rates_hart;
*length = ARRAY_SIZE(ad74413r_adc_sampling_rates_hart);
} else {
*vals = ad74413r_adc_sampling_rates;
*length = ARRAY_SIZE(ad74413r_adc_sampling_rates);
}
*type = IIO_VAL_INT;
return IIO_AVAIL_LIST;
default:
return -EINVAL;
}
}
static const struct iio_buffer_setup_ops ad74413r_buffer_ops = {
.postenable = &ad74413r_buffer_postenable,
.predisable = &ad74413r_buffer_predisable,
};
static const struct iio_trigger_ops ad74413r_trigger_ops = {
.validate_device = iio_trigger_validate_own_device,
};
static const struct iio_info ad74413r_info = {
.read_raw = &ad74413r_read_raw,
.write_raw = &ad74413r_write_raw,
.read_avail = &ad74413r_read_avail,
.update_scan_mode = &ad74413r_update_scan_mode,
};
#define AD74413R_DAC_CHANNEL(_type, extra_mask_separate) \
{ \
.type = (_type), \
.indexed = 1, \
.output = 1, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) \
| (extra_mask_separate), \
}
#define AD74413R_ADC_CHANNEL(_type, extra_mask_separate) \
{ \
.type = (_type), \
.indexed = 1, \
.output = 0, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) \
| BIT(IIO_CHAN_INFO_SAMP_FREQ) \
| (extra_mask_separate), \
.info_mask_separate_available = \
BIT(IIO_CHAN_INFO_SAMP_FREQ), \
.scan_type = { \
.sign = 'u', \
.realbits = 16, \
.storagebits = 32, \
.shift = 8, \
.endianness = IIO_BE, \
}, \
}
#define AD74413R_ADC_VOLTAGE_CHANNEL \
AD74413R_ADC_CHANNEL(IIO_VOLTAGE, BIT(IIO_CHAN_INFO_SCALE) \
| BIT(IIO_CHAN_INFO_OFFSET))
#define AD74413R_ADC_CURRENT_CHANNEL \
AD74413R_ADC_CHANNEL(IIO_CURRENT, BIT(IIO_CHAN_INFO_SCALE) \
| BIT(IIO_CHAN_INFO_OFFSET))
static struct iio_chan_spec ad74413r_voltage_output_channels[] = {
AD74413R_DAC_CHANNEL(IIO_VOLTAGE, BIT(IIO_CHAN_INFO_SCALE)),
AD74413R_ADC_CURRENT_CHANNEL,
};
static struct iio_chan_spec ad74413r_current_output_channels[] = {
AD74413R_DAC_CHANNEL(IIO_CURRENT, BIT(IIO_CHAN_INFO_SCALE)),
AD74413R_ADC_VOLTAGE_CHANNEL,
};
static struct iio_chan_spec ad74413r_voltage_input_channels[] = {
AD74413R_ADC_VOLTAGE_CHANNEL,
};
static struct iio_chan_spec ad74413r_current_input_channels[] = {
AD74413R_ADC_CURRENT_CHANNEL,
};
static struct iio_chan_spec ad74413r_current_input_loop_channels[] = {
AD74413R_DAC_CHANNEL(IIO_CURRENT, BIT(IIO_CHAN_INFO_SCALE)),
AD74413R_ADC_CURRENT_CHANNEL,
};
static struct iio_chan_spec ad74413r_resistance_input_channels[] = {
AD74413R_ADC_CHANNEL(IIO_RESISTANCE, BIT(IIO_CHAN_INFO_PROCESSED)),
};
static struct iio_chan_spec ad74413r_digital_input_channels[] = {
AD74413R_ADC_VOLTAGE_CHANNEL,
};
#define _AD74413R_CHANNELS(_channels) \
{ \
.channels = _channels, \
.num_channels = ARRAY_SIZE(_channels), \
}
#define AD74413R_CHANNELS(name) \
_AD74413R_CHANNELS(ad74413r_ ## name ## _channels)
static const struct ad74413r_channels ad74413r_channels_map[] = {
[CH_FUNC_HIGH_IMPEDANCE] = AD74413R_CHANNELS(voltage_input),
[CH_FUNC_VOLTAGE_OUTPUT] = AD74413R_CHANNELS(voltage_output),
[CH_FUNC_CURRENT_OUTPUT] = AD74413R_CHANNELS(current_output),
[CH_FUNC_VOLTAGE_INPUT] = AD74413R_CHANNELS(voltage_input),
[CH_FUNC_CURRENT_INPUT_EXT_POWER] = AD74413R_CHANNELS(current_input),
[CH_FUNC_CURRENT_INPUT_LOOP_POWER] = AD74413R_CHANNELS(current_input_loop),
[CH_FUNC_RESISTANCE_INPUT] = AD74413R_CHANNELS(resistance_input),
[CH_FUNC_DIGITAL_INPUT_LOGIC] = AD74413R_CHANNELS(digital_input),
[CH_FUNC_DIGITAL_INPUT_LOOP_POWER] = AD74413R_CHANNELS(digital_input),
[CH_FUNC_CURRENT_INPUT_EXT_POWER_HART] = AD74413R_CHANNELS(current_input),
[CH_FUNC_CURRENT_INPUT_LOOP_POWER_HART] = AD74413R_CHANNELS(current_input),
};
static int ad74413r_parse_channel_config(struct iio_dev *indio_dev,
struct fwnode_handle *channel_node)
{
struct ad74413r_state *st = iio_priv(indio_dev);
struct ad74413r_channel_config *config;
u32 index;
int ret;
ret = fwnode_property_read_u32(channel_node, "reg", &index);
if (ret) {
dev_err(st->dev, "Failed to read channel reg: %d\n", ret);
return ret;
}
if (index >= AD74413R_CHANNEL_MAX) {
dev_err(st->dev, "Channel index %u is too large\n", index);
return -EINVAL;
}
config = &st->channel_configs[index];
if (config->initialized) {
dev_err(st->dev, "Channel %u already initialized\n", index);
return -EINVAL;
}
config->func = CH_FUNC_HIGH_IMPEDANCE;
fwnode_property_read_u32(channel_node, "adi,ch-func", &config->func);
if (config->func < CH_FUNC_MIN || config->func > CH_FUNC_MAX) {
dev_err(st->dev, "Invalid channel function %u\n", config->func);
return -EINVAL;
}
if (!st->chip_info->hart_support &&
(config->func == CH_FUNC_CURRENT_INPUT_EXT_POWER_HART ||
config->func == CH_FUNC_CURRENT_INPUT_LOOP_POWER_HART)) {
dev_err(st->dev, "Unsupported HART function %u\n", config->func);
return -EINVAL;
}
if (config->func == CH_FUNC_DIGITAL_INPUT_LOGIC ||
config->func == CH_FUNC_DIGITAL_INPUT_LOOP_POWER)
st->num_comparator_gpios++;
config->gpo_comparator = fwnode_property_read_bool(channel_node,
"adi,gpo-comparator");
fwnode_property_read_u32(channel_node, "drive-strength-microamp",
&config->drive_strength);
if (!config->gpo_comparator)
st->num_gpo_gpios++;
indio_dev->num_channels += ad74413r_channels_map[config->func].num_channels;
config->initialized = true;
return 0;
}
static int ad74413r_parse_channel_configs(struct iio_dev *indio_dev)
{
struct ad74413r_state *st = iio_priv(indio_dev);
int ret;
device_for_each_child_node_scoped(st->dev, channel_node) {
ret = ad74413r_parse_channel_config(indio_dev, channel_node);
if (ret)
return ret;
}
return 0;
}
static int ad74413r_setup_channels(struct iio_dev *indio_dev)
{
struct ad74413r_state *st = iio_priv(indio_dev);
struct ad74413r_channel_config *config;
struct iio_chan_spec *channels, *chans;
unsigned int i, num_chans, chan_i;
int ret;
channels = devm_kcalloc(st->dev, sizeof(*channels),
indio_dev->num_channels, GFP_KERNEL);
if (!channels)
return -ENOMEM;
indio_dev->channels = channels;
for (i = 0; i < AD74413R_CHANNEL_MAX; i++) {
config = &st->channel_configs[i];
chans = ad74413r_channels_map[config->func].channels;
num_chans = ad74413r_channels_map[config->func].num_channels;
memcpy(channels, chans, num_chans * sizeof(*chans));
for (chan_i = 0; chan_i < num_chans; chan_i++) {
struct iio_chan_spec *chan = &channels[chan_i];
chan->channel = i;
if (chan->output)
chan->scan_index = -1;
else
chan->scan_index = i;
}
ret = ad74413r_set_channel_function(st, i, config->func);
if (ret)
return ret;
channels += num_chans;
}
return 0;
}
static int ad74413r_setup_gpios(struct ad74413r_state *st)
{
struct ad74413r_channel_config *config;
unsigned int comp_gpio_i = 0;
unsigned int gpo_gpio_i = 0;
unsigned int i;
u8 gpo_config;
u32 strength;
int ret;
for (i = 0; i < AD74413R_CHANNEL_MAX; i++) {
config = &st->channel_configs[i];
if (config->gpo_comparator) {
gpo_config = AD74413R_GPO_CONFIG_COMPARATOR;
} else {
gpo_config = AD74413R_GPO_CONFIG_LOGIC;
st->gpo_gpio_offsets[gpo_gpio_i++] = i;
}
if (config->func == CH_FUNC_DIGITAL_INPUT_LOGIC ||
config->func == CH_FUNC_DIGITAL_INPUT_LOOP_POWER) {
st->comp_gpio_offsets[comp_gpio_i++] = i;
strength = config->drive_strength;
ret = ad74413r_set_comp_drive_strength(st, i, strength);
if (ret)
return ret;
}
ret = ad74413r_set_gpo_config(st, i, gpo_config);
if (ret)
return ret;
}
return 0;
}
static void ad74413r_regulator_disable(void *regulator)
{
regulator_disable(regulator);
}
static int ad74413r_probe(struct spi_device *spi)
{
struct ad74413r_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);
st->spi = spi;
st->dev = &spi->dev;
st->chip_info = spi_get_device_match_data(spi);
if (!st->chip_info)
return -EINVAL;
mutex_init(&st->lock);
init_completion(&st->adc_data_completion);
st->regmap = devm_regmap_init(st->dev, NULL, st,
&ad74413r_regmap_config);
if (IS_ERR(st->regmap))
return PTR_ERR(st->regmap);
st->reset_gpio = devm_gpiod_get_optional(st->dev, "reset", GPIOD_OUT_LOW);
if (IS_ERR(st->reset_gpio))
return PTR_ERR(st->reset_gpio);
st->refin_reg = devm_regulator_get(st->dev, "refin");
if (IS_ERR(st->refin_reg))
return dev_err_probe(st->dev, PTR_ERR(st->refin_reg),
"Failed to get refin regulator\n");
ret = regulator_enable(st->refin_reg);
if (ret)
return ret;
ret = devm_add_action_or_reset(st->dev, ad74413r_regulator_disable,
st->refin_reg);
if (ret)
return ret;
st->sense_resistor_ohms = 100000000;
device_property_read_u32(st->dev, "shunt-resistor-micro-ohms",
&st->sense_resistor_ohms);
st->sense_resistor_ohms /= 1000000;
st->trig = devm_iio_trigger_alloc(st->dev, "%s-dev%d",
st->chip_info->name, iio_device_id(indio_dev));
if (!st->trig)
return -ENOMEM;
st->trig->ops = &ad74413r_trigger_ops;
iio_trigger_set_drvdata(st->trig, st);
ret = devm_iio_trigger_register(st->dev, st->trig);
if (ret)
return ret;
indio_dev->name = st->chip_info->name;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->info = &ad74413r_info;
indio_dev->trig = iio_trigger_get(st->trig);
ret = ad74413r_reset(st);
if (ret)
return ret;
ret = ad74413r_parse_channel_configs(indio_dev);
if (ret)
return ret;
ret = ad74413r_setup_channels(indio_dev);
if (ret)
return ret;
ret = ad74413r_setup_gpios(st);
if (ret)
return ret;
if (st->num_gpo_gpios) {
st->gpo_gpiochip.owner = THIS_MODULE;
st->gpo_gpiochip.label = st->chip_info->name;
st->gpo_gpiochip.base = -1;
st->gpo_gpiochip.ngpio = st->num_gpo_gpios;
st->gpo_gpiochip.parent = st->dev;
st->gpo_gpiochip.can_sleep = true;
st->gpo_gpiochip.set = ad74413r_gpio_set;
st->gpo_gpiochip.set_multiple = ad74413r_gpio_set_multiple;
st->gpo_gpiochip.set_config = ad74413r_gpio_set_gpo_config;
st->gpo_gpiochip.get_direction =
ad74413r_gpio_get_gpo_direction;
ret = devm_gpiochip_add_data(st->dev, &st->gpo_gpiochip, st);
if (ret)
return ret;
}
if (st->num_comparator_gpios) {
st->comp_gpiochip.owner = THIS_MODULE;
st->comp_gpiochip.label = st->chip_info->name;
st->comp_gpiochip.base = -1;
st->comp_gpiochip.ngpio = st->num_comparator_gpios;
st->comp_gpiochip.parent = st->dev;
st->comp_gpiochip.can_sleep = true;
st->comp_gpiochip.get = ad74413r_gpio_get;
st->comp_gpiochip.get_multiple = ad74413r_gpio_get_multiple;
st->comp_gpiochip.set_config = ad74413r_gpio_set_comp_config;
st->comp_gpiochip.get_direction =
ad74413r_gpio_get_comp_direction;
ret = devm_gpiochip_add_data(st->dev, &st->comp_gpiochip, st);
if (ret)
return ret;
}
ret = ad74413r_set_adc_conv_seq(st, AD74413R_CONV_SEQ_OFF);
if (ret)
return ret;
ret = devm_request_irq(st->dev, spi->irq, ad74413r_adc_data_interrupt,
0, st->chip_info->name, indio_dev);
if (ret)
return dev_err_probe(st->dev, ret, "Failed to request irq\n");
ret = devm_iio_triggered_buffer_setup(st->dev, indio_dev,
&iio_pollfunc_store_time,
&ad74413r_trigger_handler,
&ad74413r_buffer_ops);
if (ret)
return ret;
return devm_iio_device_register(st->dev, indio_dev);
}
static int ad74413r_unregister_driver(struct spi_driver *spi)
{
spi_unregister_driver(spi);
return 0;
}
static int __init ad74413r_register_driver(struct spi_driver *spi)
{
crc8_populate_msb(ad74413r_crc8_table, AD74413R_CRC_POLYNOMIAL);
return spi_register_driver(spi);
}
static const struct ad74413r_chip_info ad74412r_chip_info_data = {
.hart_support = false,
.name = "ad74412r",
};
static const struct ad74413r_chip_info ad74413r_chip_info_data = {
.hart_support = true,
.name = "ad74413r",
};
static const struct of_device_id ad74413r_dt_id[] = {
{
.compatible = "adi,ad74412r",
.data = &ad74412r_chip_info_data,
},
{
.compatible = "adi,ad74413r",
.data = &ad74413r_chip_info_data,
},
{},
};
MODULE_DEVICE_TABLE(of, ad74413r_dt_id);
static const struct spi_device_id ad74413r_spi_id[] = {
{ .name = "ad74412r", .driver_data = (kernel_ulong_t)&ad74412r_chip_info_data },
{ .name = "ad74413r", .driver_data = (kernel_ulong_t)&ad74413r_chip_info_data },
{}
};
MODULE_DEVICE_TABLE(spi, ad74413r_spi_id);
static struct spi_driver ad74413r_driver = {
.driver = {
.name = "ad74413r",
.of_match_table = ad74413r_dt_id,
},
.probe = ad74413r_probe,
.id_table = ad74413r_spi_id,
};
module_driver(ad74413r_driver,
ad74413r_register_driver,
ad74413r_unregister_driver);
MODULE_AUTHOR("Cosmin Tanislav <cosmin.tanislav@analog.com>");
MODULE_DESCRIPTION("Analog Devices AD74413R ADDAC");
MODULE_LICENSE("GPL v2");