diff options
Diffstat (limited to 'drivers/iio/addac/ad74413r.c')
| -rw-r--r-- | drivers/iio/addac/ad74413r.c | 1475 |
1 files changed, 1475 insertions, 0 deletions
diff --git a/drivers/iio/addac/ad74413r.c b/drivers/iio/addac/ad74413r.c new file mode 100644 index 000000000000..cbd9aa9b399a --- /dev/null +++ b/drivers/iio/addac/ad74413r.c @@ -0,0 +1,1475 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2021 Analog Devices, Inc. + * Author: Cosmin Tanislav <cosmin.tanislav@analog.com> + */ + +#include <asm/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; + 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; + + 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) requires 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 ____cacheline_aligned; + + 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_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_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_DIN_COMP_OUT_SHIFT_X(x) x + +#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 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 = 0; + int ret; + + for_each_set_bit_from(offset, mask, AD74413R_CHANNEL_MAX) { + 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 &= AD74413R_DIN_COMP_OUT_SHIFT_X(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 = 0; + unsigned int val; + int ret; + + ret = regmap_read(st->regmap, AD74413R_REG_DIN_COMP_OUT, &val); + if (ret) + return ret; + + for_each_set_bit_from(offset, mask, AD74413R_CHANNEL_MAX) { + unsigned int real_offset = st->comp_gpio_offsets[offset]; + + if (val & BIT(real_offset)) + *bits |= 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; + + 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) +{ + return regmap_update_bits(st->regmap, + AD74413R_REG_CH_FUNC_SETUP_X(channel), + AD74413R_CH_FUNC_SETUP_MASK, func); +} + +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 ad74413_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 * 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[-1 * AD74413R_FRAME_SIZE]; + u8 *tx_buf = st->adc_samples_tx_buf; + unsigned int channel; + int ret; + + 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); + + xfer++; + tx_buf += AD74413R_FRAME_SIZE; + rx_buf += AD74413R_FRAME_SIZE; + } + + 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 ad74413_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) + 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_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), + [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"); + + 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); + struct fwnode_handle *channel_node = NULL; + int ret; + + fwnode_for_each_available_child_node(dev_fwnode(st->dev), channel_node) { + ret = ad74413r_parse_channel_config(indio_dev, channel_node); + if (ret) + goto put_channel_node; + } + + return 0; + +put_channel_node: + fwnode_handle_put(channel_node); + + return ret; +} + +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; + 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; + + 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 = device_get_match_data(&spi->dev); + 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->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 struct spi_driver ad74413r_driver = { + .driver = { + .name = "ad74413r", + .of_match_table = ad74413r_dt_id, + }, + .probe = ad74413r_probe, +}; + +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"); |