@@ -48,6 +48,22 @@ config AD4130
To compile this driver as a module, choose M here: the module will be
called ad4130.
+
+config AD4170
+ tristate "Analog Device AD4170 ADC Driver"
+ depends on SPI
+ depends on GPIOLIB
+ select IIO_BUFFER
+ select IIO_TRIGGERED_BUFFER
+ select REGMAP_SPI
+ depends on COMMON_CLK
+ help
+ Say yes here to build support for Analog Devices AD4170 SPI analog
+ to digital converters (ADC).
+
+ To compile this driver as a module, choose M here: the module will be
+ called ad4170.
+
config AD4695
tristate "Analog Device AD4695 ADC Driver"
depends on SPI
@@ -8,6 +8,7 @@ obj-$(CONFIG_AB8500_GPADC) += ab8500-gpadc.o
obj-$(CONFIG_AD_SIGMA_DELTA) += ad_sigma_delta.o
obj-$(CONFIG_AD4000) += ad4000.o
obj-$(CONFIG_AD4130) += ad4130.o
+obj-$(CONFIG_AD4170) += ad4170.o
obj-$(CONFIG_AD4695) += ad4695.o
obj-$(CONFIG_AD7091R) += ad7091r-base.o
obj-$(CONFIG_AD7091R5) += ad7091r5.o
new file mode 100644
@@ -0,0 +1,2049 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2024 Analog Devices, Inc.
+ * Author: Ana-Maria Cusco <ana-maria.cusco@analog.com>
+ * Author: Marcelo Schmitt <marcelo.schmitt@analog.com>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/gpio/driver.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/math64.h>
+#include <linux/module.h>
+#include <linux/property.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+#include <linux/spi/spi.h>
+#include <linux/units.h>
+#include <linux/util_macros.h>
+
+#include <asm/div64.h>
+#include <linux/unaligned.h>
+
+#include <linux/iio/buffer.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/kfifo_buf.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/iio/trigger_consumer.h>
+#include "ad4170.h"
+
+#define AD4170_SINC5_AVG_CONF 0x0
+#define AD4170_SINC5_CONF 0x4
+#define AD4170_SINC3_CONF 0x6
+
+enum ad4170_regulator {
+ AD4170_AVDD_SUP,
+ AD4170_AVSS_SUP,
+ AD4170_IOVDD_SUP,
+ AD4170_REFIN1P_SUP,
+ AD4170_REFIN1N_SUP,
+ AD4170_REFIN2P_SUP,
+ AD4170_REFIN2N_SUP,
+};
+
+static const char *const ad4170_clk_sel[] = {
+ "ext-clk", "xtal"
+};
+
+static const char *const ad4170_i_out_pin_dt_props[] = {
+ "adi,excitation-pin-0",
+ "adi,excitation-pin-1",
+ "adi,excitation-pin-2",
+ "adi,excitation-pin-3",
+};
+
+static const char *const ad4170_i_out_val_dt_props[] = {
+ "adi,excitation-current-0-microamp",
+ "adi,excitation-current-1-microamp",
+ "adi,excitation-current-2-microamp",
+ "adi,excitation-current-3-microamp",
+};
+
+#define AD4170_SINC5_FS_PADDING 8
+#define AD4170_SINC3_FS_OFFSET 2
+
+#define AD4170_SINC3_MIN_FS 4
+#define AD4170_SINC3_MAX_FS 65532
+#define AD4170_SINC5_MIN_FS 1
+#define AD4170_SINC5_MAX_FS 256
+
+/* Make separate fs tables? One for SINC5 other for SINC5+AVG and SINC3? */
+static const unsigned int ad4170_filt_fs_tbl[] = {
+ 1, /* SINC5 minimum filter_fs */
+ 2,
+ 4, /* SINC5+AVG and SINC3 minimum filter_fs */
+ 8,
+ 12,
+ 16,
+ 20,
+ 40,
+ 48,
+ 80,
+ 100,
+ 256, /* SINC5 maximum filter_fs */
+ 500,
+ 1000,
+ 5000,
+ 8332,
+ 10000,
+ 25000,
+ 50000,
+ 65532 /* SINC5+AVG and SINC3 maximum filter_fs */
+};
+
+/*
+ * There are 8 of each MISC, AFE, FILTER, FILTER_FS, OFFSET, and GAIN
+ * configuration registers. That is, there are 8 miscellaneous registers, MISC0
+ * to MISC7. Each MISC register is associated with a setup; MISCN is associated
+ * with setup number N. The other 5 above mentioned types of registers have
+ * analogous structure. A setup is a set of those registers. For example,
+ * setup 1 comprises of MISC1, AFE1, FILTER1, FILTER_FS1, OFFSET1, and GAIN1
+ * registers. Also, there are 16 CHANNEL_SETUP registers (CHANNEL_SETUP0 to
+ * CHANNEL_SETUP15). Each channel setup is associated with one of the 8 possible
+ * setups. Thus, AD4170 can support up to 16 channels but, since there are only
+ * 8 available setups, channels must share settings if more than 8 channels are
+ * configured.
+ */
+struct ad4170_setup {
+ u16 misc;
+ u16 afe;
+ u16 filter;
+ u16 filter_fs;
+ u32 offset; /* For calibration purposes */
+ u32 gain; /* For calibration purposes */
+};
+
+struct ad4170_chan_info {
+ int setup_num;
+ int input_range_uv;
+ u32 scale_tbl[10][2];
+ int offset_tbl[10];
+ bool enabled;
+};
+
+static const char * const ad4170_filt_names[] = {
+ [AD4170_SINC5_AVG] = "sinc5+avg",
+ [AD4170_SINC5] = "sinc5",
+ [AD4170_SINC3] = "sinc3",
+};
+
+struct ad4170_state {
+ struct regmap *regmap;
+ struct spi_device *spi;
+ struct regulator_bulk_data supplies[7];
+ struct mutex lock; /* Protect filter, PGA, GPIO, chan read, chan config */
+ struct iio_chan_spec chans[AD4170_MAX_CHANNELS];
+ struct ad4170_chan_info chans_info[AD4170_MAX_CHANNELS];
+ struct ad4170_setup setups[AD4170_MAX_SETUPS];
+ u32 mclk_hz;
+ enum ad4170_pin_function pins_fn[AD4170_NUM_ANALOG_PINS];
+ enum ad4170_gpio_function gpio_fn[AD4170_NUM_GPIO_PINS];
+ unsigned int clock_ctrl;
+ struct clk *ext_clk;
+ struct clk_hw int_clk_hw;
+ int sps_tbl[ARRAY_SIZE(ad4170_filt_names)][ARRAY_SIZE(ad4170_filt_fs_tbl)][2];
+ struct completion completion;
+ struct iio_trigger *trig;
+ u32 data[AD4170_MAX_CHANNELS];
+
+ struct spi_transfer xfer;
+ struct spi_message msg;
+ /*
+ * DMA (thus cache coherency maintenance) requires the transfer buffers
+ * to live in their own cache lines.
+ */
+ u8 reg_write_tx_buf[6];
+ __be32 reg_read_rx_buf __aligned(IIO_DMA_MINALIGN);
+ __be16 reg_read_tx_buf;
+};
+
+static void ad4170_fill_sps_tbl(struct ad4170_state *st)
+{
+ unsigned int tmp0, tmp1, i;
+
+ /*
+ * The ODR can be calculated the same way for sinc5+avg, sinc5, and
+ * sinc3 filter types with the exception that sinc5 filter has a
+ * narrowed range of allowed FILTER_FS values.
+ */
+ for (i = AD4170_SINC3_FS_OFFSET; i < ARRAY_SIZE(ad4170_filt_fs_tbl); i++) {
+ tmp0 = div_u64_rem(st->mclk_hz, 32 * ad4170_filt_fs_tbl[i], &tmp1);
+ tmp1 = mult_frac(tmp1, MICRO, 32 * ad4170_filt_fs_tbl[i]);
+ // sinc5+avg and sinc3 havethe same SPS table. Drop one of them?
+ /* Fill sinc5+avg filter SPS table */
+ st->sps_tbl[AD4170_SINC5_AVG][i][0] = tmp0; /* Integer part */
+ st->sps_tbl[AD4170_SINC5_AVG][i][1] = tmp1; /* Fractional part */
+
+ /* Fill sinc3 filter SPS table */
+ st->sps_tbl[AD4170_SINC3][i][0] = tmp0; /* Integer part */
+ st->sps_tbl[AD4170_SINC3][i][1] = tmp1; /* Fractional part */
+ }
+ /* Sinc5 filter ODR doesn't use all FILTER_FS bits */
+ for (i = 0; i < ARRAY_SIZE(ad4170_filt_fs_tbl) - AD4170_SINC5_FS_PADDING; i++) {
+ tmp0 = div_u64_rem(st->mclk_hz, 32 * ad4170_filt_fs_tbl[i], &tmp1);
+ tmp1 = mult_frac(tmp1, MICRO, 32 * ad4170_filt_fs_tbl[i]);
+ /* Fill sinc5 filter SPS table */
+ st->sps_tbl[AD4170_SINC5][i][0] = tmp0; /* Integer part */
+ st->sps_tbl[AD4170_SINC5][i][1] = tmp1; /* Fractional part */
+ }
+}
+
+static int ad4170_get_reg_size(struct ad4170_state *st, unsigned int reg,
+ unsigned int *size)
+{
+ if (reg >= ARRAY_SIZE(ad4170_reg_size))
+ return -EINVAL;
+
+ if (!ad4170_reg_size[reg])
+ return -EINVAL;
+
+ *size = ad4170_reg_size[reg];
+
+ return 0;
+}
+
+static int ad4170_reg_access(struct iio_dev *indio_dev, unsigned int reg,
+ unsigned int writeval, unsigned int *readval)
+{
+ struct ad4170_state *st = iio_priv(indio_dev);
+
+ if (readval)
+ return regmap_read(st->regmap, reg, readval);
+
+ return regmap_write(st->regmap, reg, writeval);
+}
+
+static int ad4170_reg_write(void *context, unsigned int reg, unsigned int val)
+{
+ struct ad4170_state *st = context;
+ unsigned int size, addr;
+ int ret;
+
+ ret = ad4170_get_reg_size(st, reg, &size);
+ if (ret)
+ return ret;
+
+ addr = reg + size - 1;
+ put_unaligned_be16(addr, &st->reg_write_tx_buf[0]);
+
+ switch (size) {
+ case 4:
+ put_unaligned_be32(val, &st->reg_write_tx_buf[2]);
+ break;
+ case 3:
+ put_unaligned_be24(val, &st->reg_write_tx_buf[2]);
+ break;
+ case 2:
+ put_unaligned_be16(val, &st->reg_write_tx_buf[2]);
+ break;
+ case 1:
+ st->reg_write_tx_buf[2] = val;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return spi_write(st->spi, st->reg_write_tx_buf, size + 2);
+}
+
+static int ad4170_reg_read(void *context, unsigned int reg, unsigned int *val)
+{
+ struct ad4170_state *st = context;
+ struct spi_transfer t[] = {
+ {
+ .tx_buf = &st->reg_read_tx_buf,
+ .len = 2,
+ },
+ {
+ .rx_buf = &st->reg_read_rx_buf,
+ },
+ };
+ unsigned int size, addr;
+ int ret;
+
+ ret = ad4170_get_reg_size(st, reg, &size);
+ if (ret)
+ return ret;
+
+ addr = reg + size - 1;
+ put_unaligned_be16(AD4170_READ_MASK | addr, &st->reg_read_tx_buf);
+
+ t[1].len = size;
+
+ ret = spi_sync_transfer(st->spi, t, ARRAY_SIZE(t));
+ if (ret)
+ return ret;
+
+ switch (size) {
+ case 4:
+ *val = get_unaligned_be32(&st->reg_read_rx_buf);
+ break;
+ case 3:
+ *val = get_unaligned_be24(&st->reg_read_rx_buf);
+ break;
+ case 2:
+ *val = get_unaligned_be16(&st->reg_read_rx_buf);
+ break;
+ case 1:
+ *val = st->reg_read_rx_buf;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static const struct regmap_config ad4170_regmap_config = {
+ .reg_bits = 14,
+ .val_bits = 32,
+ .reg_format_endian = REGMAP_ENDIAN_BIG,
+ .val_format_endian = REGMAP_ENDIAN_BIG,
+ .reg_read = ad4170_reg_read,
+ .reg_write = ad4170_reg_write,
+};
+
+static int ad4170_set_mode(struct ad4170_state *st, unsigned int mode)
+{
+ return regmap_update_bits(st->regmap, AD4170_ADC_CTRL_REG,
+ AD4170_REG_CTRL_MODE_MSK,
+ FIELD_PREP(AD4170_REG_CTRL_MODE_MSK, mode));
+}
+
+/* 8 possible setups (0-7)*/
+static int ad4170_write_setup(struct ad4170_state *st, unsigned int setup_num,
+ struct ad4170_setup *setup)
+{
+ int ret;
+
+ /*
+ * It is recommended to place the ADC in standby mode or idle mode to
+ * write to OFFSET and GAIN registers.
+ */
+ ret = ad4170_set_mode(st, AD4170_ADC_CTRL_MODE_IDLE);
+ if (ret)
+ return ret;
+
+ ret = regmap_write(st->regmap, AD4170_MISC_REG(setup_num), setup->misc);
+ if (ret < 0)
+ return ret;
+
+ ret = regmap_write(st->regmap, AD4170_AFE_REG(setup_num), setup->afe);
+ if (ret < 0)
+ return ret;
+
+ ret = regmap_write(st->regmap, AD4170_FILTER_REG(setup_num),
+ setup->filter);
+ if (ret < 0)
+ return ret;
+
+ ret = regmap_write(st->regmap, AD4170_FILTER_FS_REG(setup_num),
+ setup->filter_fs);
+ if (ret < 0)
+ return ret;
+
+ ret = regmap_write(st->regmap, AD4170_OFFSET_REG(setup_num),
+ setup->offset);
+ if (ret < 0)
+ return ret;
+
+ ret = regmap_write(st->regmap, AD4170_GAIN_REG(setup_num), setup->gain);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static int ad4170_filter_to_filter_type(unsigned int filter)
+{
+ u16 f_conf = FIELD_GET(AD4170_SETUPS_FILTER_TYPE_MSK, filter);
+
+ switch (f_conf) {
+ case AD4170_SINC5_AVG_CONF:
+ return AD4170_SINC5_AVG;
+ case AD4170_SINC5_CONF:
+ return AD4170_SINC5;
+ case AD4170_SINC3_CONF:
+ return AD4170_SINC3;
+ default:
+ return -EINVAL;
+ }
+}
+
+static int ad4170_set_filter_type(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan,
+ unsigned int val)
+{
+ struct ad4170_state *st = iio_priv(indio_dev);
+ struct ad4170_chan_info *chan_info = &st->chans_info[chan->address];
+ struct ad4170_setup *setup = &st->setups[chan_info->setup_num];
+ unsigned int old_filter_fs, old_filter, filter_type_conf;
+ int ret = 0;
+
+ switch (val) {
+ case AD4170_SINC5_AVG:
+ filter_type_conf = AD4170_SINC5_AVG_CONF;
+ break;
+ case AD4170_SINC5:
+ filter_type_conf = AD4170_SINC5_CONF;
+ break;
+ case AD4170_SINC3:
+ filter_type_conf = AD4170_SINC3_CONF;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ /*
+ * The filters provide the same ODR for a given filter_fs value but
+ * there are different minimum and maximum filter_fs limits for each
+ * filter. The filter_fs value will be adjusted if the current filter_fs
+ * is out of the limits of the just requested filter. Since the
+ * filter_fs value affects the ODR (sampling_frequency), changing the
+ * filter may lead to a change in the sampling frequency.
+ */
+ iio_device_claim_direct_scoped(return -EBUSY, indio_dev) {
+ old_filter = setup->filter;
+ old_filter_fs = setup->filter_fs;
+ if (val == AD4170_SINC5_AVG || val == AD4170_SINC3) {
+ if (setup->filter_fs < AD4170_SINC3_MIN_FS)
+ setup->filter_fs = AD4170_SINC3_MIN_FS;
+ if (setup->filter_fs > AD4170_SINC3_MAX_FS)
+ setup->filter_fs = AD4170_SINC3_MAX_FS;
+
+ } else if (val == AD4170_SINC5) {
+ if (setup->filter_fs < AD4170_SINC5_MIN_FS)
+ setup->filter_fs = AD4170_SINC5_MIN_FS;
+ if (setup->filter_fs > AD4170_SINC5_MAX_FS)
+ setup->filter_fs = AD4170_SINC5_MAX_FS;
+ }
+
+ setup->filter &= ~AD4170_SETUPS_FILTER_TYPE_MSK;
+ setup->filter |= FIELD_PREP(AD4170_SETUPS_FILTER_TYPE_MSK,
+ filter_type_conf);
+
+ guard(mutex)(&st->lock);
+ ret = ad4170_write_setup(st, chan_info->setup_num, setup);
+ if (ret) {
+ setup->filter = old_filter;
+ setup->filter_fs = old_filter_fs;
+ }
+ return ret;
+ }
+ unreachable();
+}
+
+static int ad4170_get_filter_type(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan)
+{
+ struct ad4170_state *st = iio_priv(indio_dev);
+ struct ad4170_chan_info *chan_info = &st->chans_info[chan->address];
+ struct ad4170_setup *setup = &st->setups[chan_info->setup_num];
+
+ return ad4170_filter_to_filter_type(setup->filter);
+}
+
+static const struct iio_enum ad4170_filter_type_enum = {
+ .items = ad4170_filt_names,
+ .num_items = ARRAY_SIZE(ad4170_filt_names),
+ .get = ad4170_get_filter_type,
+ .set = ad4170_set_filter_type,
+};
+
+static const struct iio_chan_spec_ext_info ad4170_filter_type_ext_info[] = {
+ IIO_ENUM("filter_type", IIO_SEPARATE, &ad4170_filter_type_enum),
+ IIO_ENUM_AVAILABLE("filter_type", IIO_SHARED_BY_TYPE,
+ &ad4170_filter_type_enum),
+ { }
+};
+
+static const struct iio_chan_spec ad4170_channel_template = {
+ .type = IIO_VOLTAGE,
+ .indexed = 1,
+ .differential = 1,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_SCALE) |
+ BIT(IIO_CHAN_INFO_OFFSET) |
+ BIT(IIO_CHAN_INFO_CALIBSCALE) |
+ BIT(IIO_CHAN_INFO_CALIBBIAS) |
+ BIT(IIO_CHAN_INFO_SAMP_FREQ),
+ .info_mask_separate_available = BIT(IIO_CHAN_INFO_SCALE) |
+ BIT(IIO_CHAN_INFO_SAMP_FREQ),
+ .ext_info = ad4170_filter_type_ext_info,
+ .scan_type = {
+ .realbits = 24,
+ .storagebits = 32,
+ .endianness = IIO_BE,
+ },
+};
+
+static int _ad4170_find_table_index(const unsigned int *tbl, size_t len,
+ unsigned int val)
+{
+ unsigned int i;
+
+ for (i = 0; i < len; i++)
+ if (tbl[i] == val)
+ return i;
+
+ return -EINVAL;
+}
+
+#define ad4170_find_table_index(table, val) \
+ _ad4170_find_table_index(table, ARRAY_SIZE(table), val)
+
+static int ad4170_set_channel_enable(struct ad4170_state *st,
+ unsigned int channel, bool status)
+{
+ struct ad4170_chan_info *chan_info = &st->chans_info[channel];
+ int ret;
+
+ if (chan_info->enabled == status)
+ return 0;
+
+ ret = regmap_update_bits(st->regmap, AD4170_CHANNEL_EN_REG,
+ AD4170_CHANNEL_EN(channel),
+ status ? AD4170_CHANNEL_EN(channel) : 0);
+ if (ret)
+ return ret;
+
+ chan_info->enabled = status;
+ return 0;
+}
+
+static int ad4170_read_sample(struct iio_dev *indio_dev, unsigned int channel,
+ int *val)
+{
+ struct ad4170_state *st = iio_priv(indio_dev);
+ struct ad4170_chan_info *chan_info = &st->chans_info[channel];
+ struct ad4170_setup *setup = &st->setups[chan_info->setup_num];
+ int precision_bits = ad4170_channel_template.scan_type.realbits;
+ int ret;
+
+ guard(mutex)(&st->lock);
+ ret = ad4170_set_channel_enable(st, channel, true);
+ if (ret)
+ return ret;
+
+ reinit_completion(&st->completion);
+
+ ret = ad4170_set_mode(st, AD4170_ADC_CTRL_MODE_SINGLE);
+ if (ret)
+ return ret;
+
+ ret = wait_for_completion_timeout(&st->completion, HZ);
+ if (!ret)
+ goto out;
+
+ ret = regmap_read(st->regmap, AD4170_DATA_24b_REG, val);
+ if (ret)
+ return ret;
+
+ if (FIELD_GET(AD4170_AFE_BIPOLAR_MSK, setup->afe))
+ *val = sign_extend32(*val, precision_bits - 1);
+out:
+ ret = ad4170_set_channel_enable(st, channel, false);
+ if (ret)
+ return ret;
+
+ return IIO_VAL_INT;
+}
+
+/*
+ * Receives the device state, the number of a multiplexed input (AINP_N
+ * or AIM_N), and stores the voltage (in µV) of the specified input into the
+ * third argument. If the input number is not one of the special multiplexed
+ * inputs ((AVDD-AVSS)/5, ..., REFOUT), stores zero to the voltage argument.
+ * If a voltage regulator required by the special input is unavailable, return
+ * error code. Return 0 on success.
+ *
+ * @st: pointer to device state struct
+ * @ain_n: number of a multiplexed AD4170 input
+ * @ain_voltage: pointer to a variable where to store ain_n voltage
+ */
+static int ad4170_get_AINM_voltage(struct ad4170_state *st, int ain_n,
+ int *ain_voltage)
+{
+ int ret;
+
+ *ain_voltage = 0;
+ switch (ain_n) {
+ case AD4170_MAP_AVDD_AVSS_N:
+ ret = regulator_get_voltage(st->supplies[AD4170_AVDD_SUP].consumer);
+ if (ret < 0)
+ return ret;
+
+ *ain_voltage = ret ? ret / 5 : 0;
+ return 0;
+ case AD4170_MAP_IOVDD_DGND_N:
+ ret = regulator_get_voltage(st->supplies[AD4170_IOVDD_SUP].consumer);
+ if (ret < 0)
+ return ret;
+
+ *ain_voltage = ret ? ret / 5 : 0;
+ return 0;
+ case AD4170_MAP_AVSS:
+ ret = regulator_get_voltage(st->supplies[AD4170_AVSS_SUP].consumer);
+ if (ret < 0)
+ ret = 0; /* Assume AVSS at 0V if not provided */
+
+ /* AVSS is never above 0V, i.e., it can only be negative. */
+ *ain_voltage = -ret; /* AVSS is a negative voltage */
+ return 0;
+ case AD4170_MAP_DGND:
+ *ain_voltage = 0;
+ return 0;
+ case AD4170_MAP_REFIN1_P:
+ ret = regulator_get_voltage(st->supplies[AD4170_REFIN1P_SUP].consumer);
+ if (ret < 0)
+ return ret;
+
+ *ain_voltage = ret;
+ return 0;
+ case AD4170_MAP_REFIN1_N:
+ ret = regulator_get_voltage(st->supplies[AD4170_REFIN1N_SUP].consumer);
+ if (ret < 0)
+ return ret;
+
+ /*
+ * Making the assumption negative inputs of voltage references
+ * are either at GND level or negative with respect to GND.
+ */
+ *ain_voltage = -ret;
+ return 0;
+ case AD4170_MAP_REFIN2_P:
+ ret = regulator_get_voltage(st->supplies[AD4170_REFIN2P_SUP].consumer);
+ if (ret < 0)
+ return ret;
+
+ *ain_voltage = ret;
+ return 0;
+ case AD4170_MAP_REFIN2_N:
+ ret = regulator_get_voltage(st->supplies[AD4170_REFIN2N_SUP].consumer);
+ if (ret < 0)
+ return ret;
+
+ /*
+ * Making the assumption negative inputs of voltage references
+ * are either at GND level or negative with respect to GND.
+ */
+ *ain_voltage = -ret;
+ return 0;
+ case AD4170_MAP_REFOUT:
+ /* REFOUT is 2.5V relative to AVSS so take that into account */
+ ret = regulator_get_voltage(st->supplies[AD4170_AVSS_SUP].consumer);
+ if (ret < 0)
+ ret = 0; /* Assume AVSS at GND (0V) if not provided */
+
+ *ain_voltage = AD4170_INT_REF_2_5V - ret;
+ return 0;
+ }
+ return -EINVAL;
+}
+
+static int ad4170_validate_analog_input(struct ad4170_state *st, int pin)
+{
+ if (pin <= AD4170_MAX_ANALOG_PINS) {
+ if (st->pins_fn[pin] != AD4170_PIN_UNASIGNED)
+ return dev_err_probe(&st->spi->dev, -EINVAL,
+ "Pin %d already used with fn %u.\n",
+ pin, st->pins_fn[pin]);
+
+ st->pins_fn[pin] = AD4170_PIN_ANALOG_IN;
+ }
+ return 0;
+}
+
+static int ad4170_validate_channel_input(struct ad4170_state *st, int pin, bool com)
+{
+ /* Check common-mode input pin is mapped to a special input. */
+ if (com && (pin < AD4170_MAP_AVDD_AVSS_P || pin > AD4170_MAP_REFOUT))
+ return dev_err_probe(&st->spi->dev, -EINVAL,
+ "Invalid common-mode input pin number. %d\n",
+ pin);
+
+ /* Check differential input pin is mapped to a analog input pin. */
+ if (!com && pin > AD4170_MAX_ANALOG_PINS)
+ return dev_err_probe(&st->spi->dev, -EINVAL,
+ "Invalid analog input pin number. %d\n",
+ pin);
+
+ return ad4170_validate_analog_input(st, pin);
+}
+
+/*
+ * Verifies whether the channel input configuration is valid by checking the
+ * provided input type and input numbers.
+ * Returns 0 on valid channel input configuration. -EINVAl otherwise.
+ */
+static int ad4170_validate_channel(struct ad4170_state *st,
+ struct iio_chan_spec const *chan)
+{
+ int ret;
+
+ /* Check temperature channel mapping. */
+ if (chan->channel == AD4170_MAP_TEMP_SENSOR_P) {
+ if (chan->channel2 != AD4170_MAP_TEMP_SENSOR_N)
+ return dev_err_probe(&st->spi->dev, -EINVAL,
+ "Invalid temperature channel pin. %d\n",
+ chan->channel2);
+
+ return 0;
+ }
+
+ ret = ad4170_validate_channel_input(st, chan->channel, false);
+ if (ret < 0)
+ return ret;
+
+ ret = ad4170_validate_channel_input(st, chan->channel2, !chan->differential);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+/*
+ * Receives the device state, the channel spec, a reference selection, and
+ * returns the magnitude of the allowed input range in µV.
+ * Verifies whether the channel configuration is valid by checking the provided
+ * input type, polarity, and voltage references result in a sane input range.
+ * Returns negative error code on failure.
+ */
+static int ad4170_get_input_range(struct ad4170_state *st,
+ struct iio_chan_spec const *chan,
+ unsigned int ref_sel)
+{
+ struct ad4170_chan_info *chan_info = &st->chans_info[chan->address];
+ struct ad4170_setup *setup = &st->setups[chan_info->setup_num];
+ bool bipolar = FIELD_GET(AD4170_AFE_BIPOLAR_MSK, setup->afe);
+ int refp, refn, ain_voltage, ret;
+
+ switch (ref_sel) {
+ case AD4170_AFE_REFIN_REFIN1:
+ refp = regulator_get_voltage(st->supplies[AD4170_REFIN1P_SUP].consumer);
+ refn = regulator_get_voltage(st->supplies[AD4170_REFIN1N_SUP].consumer);
+ break;
+ case AD4170_AFE_REFIN_REFIN2:
+ refp = regulator_get_voltage(st->supplies[AD4170_REFIN2P_SUP].consumer);
+ refn = regulator_get_voltage(st->supplies[AD4170_REFIN2N_SUP].consumer);
+ break;
+ case AD4170_AFE_REFIN_AVDD:
+ refp = regulator_get_voltage(st->supplies[AD4170_AVDD_SUP].consumer);
+ ret = regulator_get_voltage(st->supplies[AD4170_AVSS_SUP].consumer);
+ /*
+ * TODO AVSS is actually optional.
+ * Should we handle -EPROBE_DEFER here?
+ */
+ if (ret < 0)
+ ret = 0; /* Assume AVSS at GND if not provided */
+
+ refn = ret;
+ break;
+ case AD4170_AFE_REFIN_REFOUT:
+ refn = regulator_get_voltage(st->supplies[AD4170_AVSS_SUP].consumer);
+ if (refn < 0)
+ refn = 0;
+
+ /* REFOUT is 2.5 V relative to AVSS */
+ /* avss-supply is never above 0V. */
+ refp = AD4170_INT_REF_2_5V - refn;
+ break;
+ default:
+ return -EINVAL;
+ }
+ if (refp < 0)
+ return refp;
+
+ if (refn < 0)
+ return refn;
+
+ /*
+ * Find out the analog input range from the channel type, polarity, and
+ * voltage reference selection.
+ * AD4170 channels are either differential or pseudo-differential.
+ */
+ /* Differential Input Voltage Range: −VREF/gain to +VREF/gain (datasheet page 6) */
+ /* Single-Ended Input Voltage Range: 0 to VREF/gain (datasheet page 6) */
+ if (chan->differential) {
+ if (!bipolar)
+ return dev_err_probe(&st->spi->dev, -EINVAL,
+ "Invalid channel %lu setup.\n",
+ chan->address);
+
+ /* Differential bipolar channel */
+ /* avss-supply is never above 0V. */
+ /* Assuming refin1n-supply not above 0V. */
+ /* Assuming refin2n-supply not above 0V. */
+ return refp + refn;
+ }
+ /*
+ * Some configurations can lead to invalid setups.
+ * For example, if AVSS = -2.5V, REF_SELECT set to REFOUT (REFOUT/AVSS),
+ * and single-ended channel configuration set, then the input range
+ * should go from 0V to +VREF (single-ended - datasheet pg 10), but
+ * REFOUT/AVSS range would be -2.5V to 0V.
+ * Check the positive reference is higher than 0V for pseudo-diff
+ * channels.
+ */
+ if (bipolar) {
+ /* Pseudo-differential bipolar channel */
+ /* Input allowed to swing from GND to +VREF */
+ if (refp <= 0)
+ return dev_err_probe(&st->spi->dev, -EINVAL,
+ "Invalid setup for channel %lu.\n",
+ chan->address);
+
+ return refp;
+ }
+
+ /* Pseudo-differential unipolar channel */
+ /* Input allowed to swing from IN- to +VREF */
+ if (refp <= 0)
+ return dev_err_probe(&st->spi->dev, -EINVAL,
+ "Invalid setup for channel %lu.\n",
+ chan->address);
+
+ ret = ad4170_get_AINM_voltage(st, chan->channel2, &ain_voltage);
+ if (ret < 0)
+ return ret;
+
+ if (refp - ain_voltage <= 0)
+ return dev_err_probe(&st->spi->dev, -EINVAL,
+ "Invalid setup for channel %lu.\n",
+ chan->address);
+
+ return refp - ain_voltage;
+}
+
+static int ad4170_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long info)
+{
+ struct ad4170_state *st = iio_priv(indio_dev);
+ struct ad4170_chan_info *chan_info = &st->chans_info[chan->address];
+ struct ad4170_setup *setup = &st->setups[chan_info->setup_num];
+ enum ad4170_filter_type f_type;
+ unsigned int pga, fs_idx;
+
+ switch (info) {
+ case IIO_CHAN_INFO_RAW:
+ iio_device_claim_direct_scoped(return -EBUSY, indio_dev)
+ return ad4170_read_sample(indio_dev, chan->address, val);
+ unreachable();
+ case IIO_CHAN_INFO_SCALE:
+ pga = FIELD_GET(AD4170_AFE_PGA_GAIN_MSK, setup->afe);
+ *val = chan_info->scale_tbl[pga][0];
+ *val2 = chan_info->scale_tbl[pga][1];
+ return IIO_VAL_INT_PLUS_NANO;
+ case IIO_CHAN_INFO_OFFSET:
+ pga = FIELD_GET(AD4170_AFE_PGA_GAIN_MSK, setup->afe);
+ *val = chan_info->offset_tbl[pga];
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ f_type = ad4170_filter_to_filter_type(setup->filter);
+ fs_idx = find_closest(setup->filter_fs, ad4170_filt_fs_tbl,
+ ARRAY_SIZE(ad4170_filt_fs_tbl));
+ *val = st->sps_tbl[f_type][fs_idx][0];
+ *val2 = st->sps_tbl[f_type][fs_idx][1];
+ return IIO_VAL_INT_PLUS_MICRO;
+ case IIO_CHAN_INFO_CALIBBIAS:
+ *val = setup->offset;
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_CALIBSCALE:
+ *val = setup->gain;
+ return IIO_VAL_INT;
+ default:
+ return -EINVAL;
+ }
+}
+
+static int ad4170_fill_scale_tbl(struct iio_dev *indio_dev, int channel)
+{
+ struct ad4170_state *st = iio_priv(indio_dev);
+ struct ad4170_chan_info *chan_info = &st->chans_info[channel];
+ struct ad4170_setup *setup = &st->setups[chan_info->setup_num];
+ const struct iio_chan_spec *chan = &indio_dev->channels[channel];
+ bool bipolar = FIELD_GET(AD4170_AFE_BIPOLAR_MSK, setup->afe);
+ int ch_resolution = chan->scan_type.realbits - bipolar;
+ int pga, ainm_voltage, ret;
+ unsigned long long offset;
+
+ ainm_voltage = 0;
+ if (chan->channel2 > AD4170_MAP_TEMP_SENSOR_N) {
+ ret = ad4170_get_AINM_voltage(st, chan->channel2, &ainm_voltage);
+ if (ret < 0)
+ return dev_err_probe(&st->spi->dev, ret,
+ "Failed to fill scale table\n");
+ }
+
+ for (pga = 0; pga < AD4170_PGA_OPTIONS; pga++) {
+ u64 nv;
+ unsigned int lshift, rshift;
+
+ /*
+ * The scale factor to get ADC output codes to values in mV
+ * units is given by:
+ * _scale = (input_range / gain) / 2^precision
+ * AD4170 gain is a power of 2 so the above can be written as
+ * _scale = input_range / 2^(precision + gain)
+ * Keep the input range in µV before right shift to preserve
+ * scale precision.
+ */
+ nv = (u64)chan_info->input_range_uv * NANO;
+ lshift = (pga >> 3 & 1); /* handle cases 8 and 9 */
+ rshift = ch_resolution + (pga & 0x7) - lshift;
+ chan_info->scale_tbl[pga][0] = 0;
+ chan_info->scale_tbl[pga][1] = div_u64(nv >> rshift, MILLI);
+
+ /*
+ * If the negative input is not at GND, the conversion result
+ * (which is relative to IN-) will be offset by the level at IN-.
+ * Use the scale factor the other way around to go from a known
+ * voltage to the corresponding ADC output code.
+ * With that, we are able to get to what would be the output
+ * code for the voltage at the negative input.
+ * If the negative input is not fixed, there is no offset.
+ */
+ offset = ((unsigned long long)ainm_voltage) * MICRO;
+ offset = DIV_ROUND_CLOSEST_ULL(offset, chan_info->scale_tbl[pga][1]);
+
+ /*
+ * After divided by the scale, offset will always fit into 31
+ * bits. For _raw + _offset to be relative to GND, the value
+ * provided as _offset is of opposite sign than the real offset.
+ */
+ chan_info->offset_tbl[pga] = -(int)(offset);
+ }
+ return 0;
+}
+
+static int ad4170_read_avail(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ const int **vals, int *type, int *length,
+ long info)
+{
+ struct ad4170_state *st = iio_priv(indio_dev);
+ struct ad4170_chan_info *chan_info = &st->chans_info[chan->address];
+ struct ad4170_setup *setup = &st->setups[chan_info->setup_num];
+ enum ad4170_filter_type f_type = ad4170_filter_to_filter_type(setup->filter);
+
+ switch (info) {
+ case IIO_CHAN_INFO_SCALE:
+ *vals = (int *)chan_info->scale_tbl;
+ *length = ARRAY_SIZE(chan_info->scale_tbl) * 2;
+ *type = IIO_VAL_INT_PLUS_NANO;
+ return IIO_AVAIL_LIST;
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ switch (f_type) {
+ case AD4170_SINC5_AVG:
+ fallthrough;
+ case AD4170_SINC3:
+ *vals = (int *)&st->sps_tbl[f_type][AD4170_SINC3_FS_OFFSET];
+ *length = (ARRAY_SIZE(ad4170_filt_fs_tbl)
+ - AD4170_SINC3_FS_OFFSET) * 2;
+ break;
+ case AD4170_SINC5:
+ *vals = (int *)st->sps_tbl[f_type];
+ *length = (ARRAY_SIZE(ad4170_filt_fs_tbl)
+ - AD4170_SINC5_FS_PADDING) * 2;
+ break;
+ default:
+ return -EINVAL;
+ }
+ *type = IIO_VAL_INT_PLUS_MICRO;
+
+ return IIO_AVAIL_LIST;
+ default:
+ return -EINVAL;
+ }
+}
+
+static int ad4170_write_raw_get_fmt(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ long info)
+{
+ switch (info) {
+ case IIO_CHAN_INFO_SCALE:
+ return IIO_VAL_INT_PLUS_NANO;
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ return IIO_VAL_INT_PLUS_MICRO;
+ case IIO_CHAN_INFO_CALIBBIAS:
+ case IIO_CHAN_INFO_CALIBSCALE:
+ return IIO_VAL_INT;
+ default:
+ return -EINVAL;
+ }
+}
+
+static int ad4170_set_pga(struct iio_dev *indio_dev, struct ad4170_state *st,
+ unsigned int channel_addr, int val, int val2)
+{
+ struct ad4170_chan_info *chan_info = &st->chans_info[channel_addr];
+ struct ad4170_setup *setup = &st->setups[chan_info->setup_num];
+ unsigned int old_pga = FIELD_GET(AD4170_AFE_PGA_GAIN_MSK, setup->afe);
+ unsigned int pga;
+ int ret = 0;
+
+ for (pga = 0; pga < AD4170_PGA_OPTIONS; pga++) {
+ if (val == chan_info->scale_tbl[pga][0] &&
+ val2 == chan_info->scale_tbl[pga][1])
+ break;
+ }
+
+ if (pga == AD4170_PGA_OPTIONS)
+ return -EINVAL;
+
+ if (pga == old_pga)
+ return 0;
+
+ setup->afe &= ~AD4170_AFE_PGA_GAIN_MSK;
+ setup->afe |= FIELD_PREP(AD4170_AFE_PGA_GAIN_MSK, pga);
+
+ guard(mutex)(&st->lock);
+ ret = ad4170_write_setup(st, chan_info->setup_num, setup);
+ if (ret) {
+ setup->afe &= ~AD4170_AFE_PGA_GAIN_MSK;
+ setup->afe |= FIELD_PREP(AD4170_AFE_PGA_GAIN_MSK, old_pga);
+ }
+
+ return ret;
+}
+
+static int ad4170_set_channel_freq(struct ad4170_state *st,
+ unsigned int channel_addr, int val, int val2)
+{
+ struct ad4170_chan_info *chan_info = &st->chans_info[channel_addr];
+ struct ad4170_setup *setup = &st->setups[chan_info->setup_num];
+ enum ad4170_filter_type f_type = ad4170_filter_to_filter_type(setup->filter);
+ int offset, padding, i, ret = 0;
+ unsigned int old_filter_fs;
+
+ switch (f_type) {
+ case AD4170_SINC5_AVG:
+ fallthrough;
+ case AD4170_SINC3:
+ offset = AD4170_SINC3_FS_OFFSET;
+ padding = 0;
+ break;
+ case AD4170_SINC5:
+ offset = 0;
+ padding = AD4170_SINC5_FS_PADDING;
+ break;
+ }
+
+ for (i = offset; i < ARRAY_SIZE(ad4170_filt_fs_tbl) - padding; i++) {
+ if (st->sps_tbl[f_type][i][0] == val &&
+ st->sps_tbl[f_type][i][1] == val2)
+ break;
+ }
+ if (i >= ARRAY_SIZE(ad4170_filt_fs_tbl) - padding)
+ return -EINVAL;
+
+ old_filter_fs = setup->filter_fs;
+ setup->filter_fs = ad4170_filt_fs_tbl[i];
+
+ guard(mutex)(&st->lock);
+ ret = ad4170_write_setup(st, chan_info->setup_num, setup);
+ if (ret)
+ setup->filter_fs = old_filter_fs;
+
+ return ret;
+}
+
+static int ad4170_set_calib_gain(struct iio_dev *indio_dev, int addr, int val)
+{
+ struct ad4170_state *st = iio_priv(indio_dev);
+ struct ad4170_chan_info *chan_info = &st->chans_info[addr];
+ struct ad4170_setup *setup = &st->setups[chan_info->setup_num];
+ u32 old_gain;
+ int ret;
+
+ old_gain = setup->gain;
+ setup->gain = val;
+
+ guard(mutex)(&st->lock);
+ ret = ad4170_write_setup(st, chan_info->setup_num, setup);
+ if (ret)
+ setup->gain = old_gain;
+
+ return ret;
+}
+
+static int ad4170_set_calib_offset(struct iio_dev *indio_dev, int addr, int val)
+{
+ struct ad4170_state *st = iio_priv(indio_dev);
+ struct ad4170_chan_info *chan_info = &st->chans_info[addr];
+ struct ad4170_setup *setup = &st->setups[chan_info->setup_num];
+ u32 old_offset;
+ int ret;
+
+ old_offset = setup->offset;
+ setup->offset = val;
+
+ guard(mutex)(&st->lock);
+ ret = ad4170_write_setup(st, chan_info->setup_num, setup);
+ if (ret)
+ setup->offset = old_offset;
+
+ return ret;
+}
+
+static int ad4170_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val, int val2, long info)
+{
+ struct ad4170_state *st = iio_priv(indio_dev);
+
+ iio_device_claim_direct_scoped(return -EBUSY, indio_dev) {
+ switch (info) {
+ case IIO_CHAN_INFO_SCALE:
+ return ad4170_set_pga(indio_dev, st, chan->address, val,
+ val2);
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ return ad4170_set_channel_freq(st, chan->address, val,
+ val2);
+ case IIO_CHAN_INFO_CALIBBIAS:
+ return ad4170_set_calib_offset(indio_dev, chan->address,
+ val);
+ case IIO_CHAN_INFO_CALIBSCALE:
+ return ad4170_set_calib_gain(indio_dev, chan->address,
+ val);
+ default:
+ return -EINVAL;
+ }
+ }
+ unreachable();
+}
+
+static int ad4170_update_scan_mode(struct iio_dev *indio_dev,
+ const unsigned long *active_scan_mask)
+{
+ struct ad4170_state *st = iio_priv(indio_dev);
+ unsigned int channel;
+ int ret;
+
+ guard(mutex)(&st->lock);
+
+ for_each_set_bit(channel, active_scan_mask, indio_dev->num_channels) {
+ ret = ad4170_set_channel_enable(st, channel, true);
+ if (ret)
+ return ret;
+ }
+ return 0;
+}
+
+static const struct iio_info ad4170_info = {
+ .read_raw = ad4170_read_raw,
+ .read_avail = ad4170_read_avail,
+ .write_raw = ad4170_write_raw,
+ .write_raw_get_fmt = ad4170_write_raw_get_fmt,
+ .update_scan_mode = ad4170_update_scan_mode,
+ .debugfs_reg_access = ad4170_reg_access,
+};
+
+static int ad4170_soft_reset(struct ad4170_state *st)
+{
+ int ret;
+
+ ret = regmap_write(st->regmap, AD4170_INTERFACE_CONFIG_A_REG,
+ AD4170_SW_RESET_MSK);
+ if (ret < 0)
+ return ret;
+
+ /*
+ * AD4170-4 requires a minimum of 1 ms between any reset event and a
+ * register read/write transaction.
+ */
+ fsleep(AD4170_RESET_SLEEP_US);
+
+ return 0;
+}
+
+static void ad4170_clk_disable_unprepare(void *clk)
+{
+ clk_disable_unprepare(clk);
+}
+
+static int ad4170_parse_pin_muxing(struct iio_dev *indio_dev)
+{
+ struct ad4170_state *st = iio_priv(indio_dev);
+ struct device *dev = &st->spi->dev;
+ u32 pin_muxing;
+ u8 aux;
+ int ret;
+
+ /*
+ * Optional adi,dig-aux1 defaults to 0, DIG_AUX1 pin disabled.
+ */
+ aux = AD4170_DIG_AUX1_DISABLED;
+ ret = device_property_read_u8(dev, "adi,dig-aux1", &aux);
+ if (ret) {
+ if (aux < AD4170_DIG_AUX1_DISABLED || aux > AD4170_DIG_AUX1_SYNC)
+ return dev_err_probe(dev, -EINVAL,
+ "Invalid adi,dig-aux1: %u\n", aux);
+ }
+ pin_muxing |= FIELD_PREP(AD4170_PIN_MUXING_DIG_AUX1_CTRL_MSK, aux);
+
+ /*
+ * Optional adi,dig-aux2 defaults to 0, DIG_AUX2 pin disabled.
+ */
+ aux = AD4170_DIG_AUX2_DISABLED;
+ ret = device_property_read_u8(dev, "adi,dig-aux2", &aux);
+ if (ret) {
+ if (aux < AD4170_DIG_AUX2_DISABLED || aux > AD4170_DIG_AUX2_SYNC)
+ return dev_err_probe(dev, -EINVAL,
+ "Invalid adi,dig-aux2: %u\n", aux);
+ }
+ pin_muxing |= FIELD_PREP(AD4170_PIN_MUXING_DIG_AUX2_CTRL_MSK, aux);
+
+ /*
+ * Optional adi,sync-option defaults to 1, standard sync functionality.
+ */
+ aux = AD4170_SYNC_STANDARD;
+ ret = device_property_read_u8(dev, "adi,sync-option", &aux);
+ if (ret) {
+ if (aux < AD4170_SYNC_DISABLED || aux > AD4170_SYNC_ALTERNATE)
+ return dev_err_probe(dev, -EINVAL,
+ "Invalid adi,sync-option: %u\n", aux);
+ }
+ pin_muxing |= FIELD_PREP(AD4170_PIN_MUXING_SYNC_CTRL_MSK, aux);
+
+ return regmap_write(st->regmap, AD4170_PIN_MUXING_REG, pin_muxing);
+}
+
+static int ad4170_parse_setup(struct ad4170_state *st,
+ struct fwnode_handle *child,
+ struct ad4170_setup *setup)
+{
+ struct device *dev = &st->spi->dev;
+ u32 tmp;
+ u16 aux16;
+ u8 aux;
+ int ret;
+
+ /* ADC input chopping setup */
+ aux16 = AD4170_MISC_CHOP_ADC_OFF;
+ ret = fwnode_property_read_u16(child, "adi,chop-adc", &aux16);
+ if (!ret) {
+ ret = ad4170_find_table_index(ad4170_chop_adc_tbl, aux16);
+ if (ret < 0)
+ return dev_err_probe(dev, ret,
+ "Invalid ADC chop config: %u\n",
+ aux16);
+ }
+ setup->misc |= FIELD_PREP(AD4170_MISC_CHOP_ADC_MSK, aux16);
+
+ /* Burnout current setup */
+ tmp = AD4170_BURNOUT_OFF;
+ fwnode_property_read_u32(child, "adi,burnout-current-nanoamp", &tmp);
+ if (!ret) {
+ ret = ad4170_find_table_index(ad4170_burnout_current_na_tbl, tmp);
+ return dev_err_probe(dev, ret,
+ "Invalid burnout current %unA\n", tmp);
+ }
+ setup->misc |= FIELD_PREP(AD4170_MISC_BURNOUT_MSK, tmp);
+
+ /* Positive reference buffer setup */
+ tmp = AD4170_REF_BUF_PRE; /* Default to have precharge buffer enabled. */
+ ret = fwnode_property_read_u32(child, "adi,buffered-positive", &tmp);
+ if (ret) {
+ if (tmp < AD4170_REF_BUF_PRE || tmp > AD4170_REF_BUF_BYPASS)
+ return dev_err_probe(dev, -EINVAL,
+ "Invalid adi,buffered-positive: %u\n",
+ tmp);
+ }
+ setup->afe |= FIELD_PREP(AD4170_AFE_REF_BUF_P_MSK, tmp);
+
+ /* Negative reference buffer setup */
+ tmp = AD4170_REF_BUF_PRE; /* Default to have precharge buffer enabled. */
+ ret = fwnode_property_read_u32(child, "adi,buffered-negative", &tmp);
+ if (ret) {
+ if (tmp < AD4170_REF_BUF_PRE || tmp > AD4170_REF_BUF_BYPASS)
+ return dev_err_probe(dev, -EINVAL,
+ "Invalid adi,buffered-negative: %u\n",
+ tmp);
+ }
+ setup->afe |= FIELD_PREP(AD4170_AFE_REF_BUF_M_MSK, tmp);
+
+ /* Voltage reference selection */
+ aux = AD4170_AFE_REFIN_REFOUT; /* Default reference selection. */
+ fwnode_property_read_u8(child, "adi,reference-select", &aux);
+ if (aux >= AD4170_AFE_REFIN_AVDD)
+ return dev_err_probe(dev, -EINVAL,
+ "Invalid reference selected %u\n", aux);
+ setup->afe |= FIELD_PREP(AD4170_AFE_REF_SELECT_MSK, aux);
+
+ return 0;
+}
+
+static int ad4170_parse_channel_type(struct device *dev,
+ struct fwnode_handle *child,
+ struct iio_chan_spec *chan)
+{
+ u32 pins[2];
+ int ret;
+
+ ret = fwnode_property_read_u32_array(child, "diff-channels", pins,
+ ARRAY_SIZE(pins));
+ if (!ret) {
+ chan->differential = true;
+ chan->channel = pins[0];
+ chan->channel2 = pins[1];
+ return 0;
+ }
+ ret = fwnode_property_read_u32(child, "single-channel", &pins[0]);
+ if (!ret) {
+ chan->differential = false;
+ chan->channel = pins[0];
+
+ ret = fwnode_property_read_u32(child, "common-mode-channel",
+ &pins[1]);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "single-ended channels must define common-mode-channel\n");
+
+ chan->channel2 = pins[1];
+ return 0;
+ }
+ return dev_err_probe(dev, ret,
+ "Channel must define one of diff-channels or single-channel.\n");
+}
+
+static int ad4170_parse_channel_node(struct iio_dev *indio_dev,
+ struct fwnode_handle *child, int chan_num)
+{
+ struct ad4170_state *st = iio_priv(indio_dev);
+ unsigned int index;
+ struct device *dev = &st->spi->dev;
+ struct ad4170_chan_info *chan_info;
+ struct ad4170_setup *setup;
+ struct iio_chan_spec *chan;
+ u8 ref_select;
+ bool bipolar;
+ int ret;
+
+ ret = fwnode_property_read_u32(child, "reg", &index);
+ if (ret)
+ return ret;
+
+ if (index >= AD4170_MAX_CHANNELS)
+ return dev_err_probe(dev, -EINVAL,
+ "Channel idx greater than no of channels\n");
+
+ chan = &st->chans[chan_num];
+ chan_info = &st->chans_info[chan_num];
+
+ *chan = ad4170_channel_template;
+ chan->address = chan_num; /* Channel index in ad4170_state chans array */
+ chan->scan_index = index; /* Index to use with the sequencer */
+
+ chan_info->setup_num = AD4170_INVALID_SETUP_SLOT;
+ ret = fwnode_property_read_u32(child, "adi,config-setup-number",
+ &chan_info->setup_num);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "Failed to read adi,config-setup-number\n");
+
+ if (chan_info->setup_num >= AD4170_MAX_SETUPS)
+ return dev_err_probe(dev, -EINVAL,
+ "Invalid adi,config-setup-number: %d\n",
+ chan_info->setup_num);
+
+ setup = &st->setups[chan_info->setup_num];
+ ret = ad4170_parse_setup(st, child, setup);
+ if (ret)
+ return ret;
+
+ ret = ad4170_parse_channel_type(dev, child, chan);
+ if (ret < 0)
+ return ret;
+
+ bipolar = fwnode_property_read_bool(child, "bipolar");
+ setup->afe |= FIELD_PREP(AD4170_AFE_BIPOLAR_MSK, bipolar);
+ if (bipolar)
+ chan->scan_type.sign = 's';
+ else
+ chan->scan_type.sign = 'u';
+
+ ref_select = FIELD_GET(AD4170_AFE_REF_SELECT_MSK, setup->afe);
+ ret = ad4170_validate_channel(st, chan);
+ if (ret < 0)
+ return ret;
+
+ ret = ad4170_get_input_range(st, chan, ref_select);
+ if (ret < 0)
+ return dev_err_probe(dev, ret, "Cannot use reference %u\n",
+ ref_select);
+
+ chan_info->input_range_uv = ret;
+ return 0;
+}
+
+static int ad4170_parse_channels(struct iio_dev *indio_dev)
+{
+ struct ad4170_state *st = iio_priv(indio_dev);
+ struct device *dev = &st->spi->dev;
+ int chan_num, i, ret;
+
+ chan_num = 0;
+ device_for_each_child_node_scoped(dev, child) {
+ ret = ad4170_parse_channel_node(indio_dev, child, chan_num);
+ if (ret)
+ return ret;
+
+ chan_num++;
+ }
+ for (i = 0; i < AD4170_MAX_CHANNELS; i++)
+ if (st->chans[i].scan_index == 0)
+ break;
+
+ /*
+ * When more than one channel is enabled, channel 0 must always be used.
+ */
+ if (chan_num > 1 && i == AD4170_MAX_CHANNELS)
+ return dev_err_probe(dev, -EINVAL,
+ "Channel 0 must be configured\n");
+
+ indio_dev->channels = st->chans;
+ indio_dev->num_channels = chan_num;
+ return 0;
+}
+
+/*
+ * Parses firmware data describing output current source setup. There are 4
+ * excitation currents (IOUT0 to IOUT3) that can be configured independently.
+ * Excitation currents are added if they are output on the same pin.
+ */
+static int ad4170_parse_exc_current(struct iio_dev *indio_dev)
+{
+ struct ad4170_state *st = iio_priv(indio_dev);
+ struct device *dev = &st->spi->dev;
+ int gpio_number;
+ u16 current_src;
+ u32 pin, val;
+ int i, ret;
+
+ for (i = 0; i < AD4170_NUM_CURRENT_SRC; i++) {
+ /* Parse excitation current output pin properties. */
+ pin = AD4170_CURRENT_IOUT_AIN0;
+ ret = fwnode_property_read_u32(dev->fwnode,
+ ad4170_i_out_pin_dt_props[i],
+ &pin);
+ if (!ret) {
+ ret = ad4170_find_table_index(ad4170_iout_pin_tbl, pin);
+ if (ret < 0)
+ return dev_err_probe(dev, ret,
+ "Invalid %s: %u\n",
+ ad4170_i_out_pin_dt_props[i],
+ pin);
+ }
+ current_src |= FIELD_PREP(AD4170_CURRENT_SRC_I_OUT_PIN_MSK, pin);
+
+ /* Parse excitation current value properties. */
+ val = AD4170_I_OUT_0UA;
+ ret = fwnode_property_read_u32(dev->fwnode,
+ ad4170_i_out_val_dt_props[i],
+ &val);
+ if (!ret) {
+ ret = ad4170_find_table_index(ad4170_iout_current_ua_tbl,
+ val);
+ if (ret < 0)
+ return dev_err_probe(dev, ret,
+ "Invalid %s: %uuA\n",
+ ad4170_i_out_val_dt_props[i],
+ val);
+ }
+ current_src |= FIELD_PREP(AD4170_CURRENT_SRC_I_OUT_VAL_MSK, val);
+
+ /*
+ * The excitation currents can be added by outputting them on
+ * the same pin so don't prevent a pin from being assigned for
+ * current output multiple times.
+ */
+ if (pin >= AD4170_CURRENT_IOUT_GPIO0) {
+ gpio_number = pin - AD4170_CURRENT_IOUT_GPIO0;
+ st->gpio_fn[gpio_number] = AD4170_GPIO_AC_EXCITATION;
+ } else if (val > AD4170_I_OUT_0UA) {
+ st->pins_fn[pin] = AD4170_PIN_CURRENT_OUT;
+ }
+
+ ret = regmap_write(st->regmap, AD4170_CURRENT_SRC_REG(i),
+ current_src);
+ if (ret < 0)
+ return ret;
+
+ current_src = 0; /* Clear temporary variable. */
+ }
+ return 0;
+}
+
+static void ad4170_disable_supplies(void *data)
+{
+ struct ad4170_state *st = data;
+
+ regulator_bulk_disable(ARRAY_SIZE(st->supplies), st->supplies);
+}
+
+static struct ad4170_state *clk_hw_to_ad4170(struct clk_hw *hw)
+{
+ return container_of(hw, struct ad4170_state, int_clk_hw);
+}
+
+static unsigned long ad4170_sel_clk(struct ad4170_state *st,
+ unsigned int clk_sel)
+{
+ st->clock_ctrl &= ~AD4170_CLOCK_CTRL_CLOCKSEL_MSK;
+ st->clock_ctrl |= FIELD_PREP(AD4170_CLOCK_CTRL_CLOCKSEL_MSK, clk_sel);
+ return regmap_write(st->regmap, AD4170_CLOCK_CTRL_REG, st->clock_ctrl);
+}
+
+static unsigned long ad4170_clk_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ return AD4170_INT_FREQ_16MHZ;
+}
+
+static int ad4170_clk_output_is_enabled(struct clk_hw *hw)
+{
+ struct ad4170_state *st = clk_hw_to_ad4170(hw);
+ u32 clk_sel;
+
+ clk_sel = FIELD_GET(AD4170_CLOCK_CTRL_CLOCKSEL_MSK, st->clock_ctrl);
+ return clk_sel == AD4170_INTERNAL_OSC_OUTPUT;
+}
+
+static int ad4170_clk_output_prepare(struct clk_hw *hw)
+{
+ struct ad4170_state *st = clk_hw_to_ad4170(hw);
+
+ return ad4170_sel_clk(st, AD4170_INTERNAL_OSC_OUTPUT);
+}
+
+static void ad4170_clk_output_unprepare(struct clk_hw *hw)
+{
+ struct ad4170_state *st = clk_hw_to_ad4170(hw);
+
+ ad4170_sel_clk(st, AD4170_INTERNAL_OSC);
+}
+
+static const struct clk_ops ad4170_int_clk_ops = {
+ .recalc_rate = ad4170_clk_recalc_rate,
+ .is_enabled = ad4170_clk_output_is_enabled,
+ .prepare = ad4170_clk_output_prepare,
+ .unprepare = ad4170_clk_output_unprepare,
+};
+
+static int ad4170_register_clk_provider(struct iio_dev *indio_dev)
+{
+ struct ad4170_state *st = iio_priv(indio_dev);
+ struct device *dev = indio_dev->dev.parent;
+ struct fwnode_handle *fwnode = dev_fwnode(dev);
+ struct clk_init_data init = {};
+ int ret;
+
+ if (!IS_ENABLED(CONFIG_COMMON_CLK))
+ return 0;
+
+ init.name = fwnode_get_name(fwnode);
+ init.ops = &ad4170_int_clk_ops;
+
+ st->int_clk_hw.init = &init;
+ ret = devm_clk_hw_register(dev, &st->int_clk_hw);
+ if (ret)
+ return ret;
+
+ return devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get,
+ &st->int_clk_hw);
+}
+
+static int ad4170_clock_select(struct iio_dev *indio_dev)
+{
+ struct ad4170_state *st = iio_priv(indio_dev);
+ struct device *dev = &st->spi->dev;
+ int ret;
+
+ st->mclk_hz = AD4170_INT_FREQ_16MHZ;
+ ret = device_property_match_property_string(dev, "clock-names",
+ ad4170_clk_sel,
+ ARRAY_SIZE(ad4170_clk_sel));
+ if (ret < 0) {
+ /* Use internal clock reference */
+ st->clock_ctrl |= FIELD_PREP(AD4170_CLOCK_CTRL_CLOCKSEL_MSK,
+ AD4170_INTERNAL_OSC_OUTPUT);
+ return ad4170_register_clk_provider(indio_dev);
+ }
+
+ /* Use external clock reference */
+ st->ext_clk = devm_clk_get(dev, ad4170_clk_sel[ret]);
+ if (IS_ERR(st->ext_clk)) {
+ if (PTR_ERR(st->ext_clk) == -EPROBE_DEFER)
+ return -EPROBE_DEFER;
+
+ return dev_err_probe(dev, PTR_ERR(st->ext_clk),
+ "Failed to get external clock\n");
+ }
+ st->clock_ctrl |= FIELD_PREP(AD4170_CLOCK_CTRL_CLOCKSEL_MSK,
+ AD4170_EXTERNAL_OSC + ret);
+
+ ret = clk_prepare_enable(st->ext_clk);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "Failed to enable external clock\n");
+
+ ret = devm_add_action_or_reset(dev, ad4170_clk_disable_unprepare,
+ st->ext_clk);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "Failed to add clock unwind action\n");
+
+ st->mclk_hz = clk_get_rate(st->ext_clk);
+ if (st->mclk_hz < AD4170_EXT_FREQ_MHZ_MIN ||
+ st->mclk_hz > AD4170_EXT_FREQ_MHZ_MAX) {
+ return dev_err_probe(dev, -EINVAL,
+ "Invalid external clock frequency %u\n",
+ st->mclk_hz);
+ }
+ return 0;
+}
+
+static int ad4170_parse_pw_switch(struct ad4170_state *st, struct device *dev)
+{
+ bool pdsw0, pdsw1;
+
+ pdsw0 = device_property_read_bool(dev, "adi,gpio0-power-down-switch");
+ pdsw1 = device_property_read_bool(dev, "adi,gpio1-power-down-switch");
+
+ /*
+ * Error if a GPIO is assigned to be both excitation current output and
+ * power switch.
+ */
+ if (pdsw0) {
+ if (st->gpio_fn[0] != AD4170_GPIO_UNASIGNED)
+ return dev_err_probe(&st->spi->dev, -EINVAL,
+ "GPIO 0 already used with fn %u\n",
+ st->gpio_fn[0]);
+
+ st->gpio_fn[0] = AD4170_GPIO_PW_DOW_SWITCH;
+ }
+ if (pdsw1) {
+ if (st->gpio_fn[1] != AD4170_GPIO_UNASIGNED)
+ return dev_err_probe(&st->spi->dev, -EINVAL,
+ "GPIO 1 already used with fn %u\n",
+ st->gpio_fn[1]);
+
+ st->gpio_fn[1] = AD4170_GPIO_PW_DOW_SWITCH;
+ }
+ return regmap_update_bits(st->regmap, AD4170_POWER_DOWN_SW_REG,
+ AD4170_POWER_DOWN_SW_PDSW0_MSK |
+ AD4170_POWER_DOWN_SW_PDSW1_MSK,
+ pdsw0 | pdsw1);
+}
+
+static int ad4170_parse_vbias(struct ad4170_state *st, struct device *dev)
+{
+ u32 vbias_pins[AD4170_MAX_ANALOG_PINS];
+ unsigned int i, val;
+ u32 num_vbias_pins;
+ int ret;
+
+ ret = device_property_count_u32(dev, "adi,vbias-pins");
+ if (ret > 0) {
+ if (ret > AD4170_MAX_ANALOG_PINS)
+ return dev_err_probe(dev, -EINVAL,
+ "Too many vbias pins %u\n", ret);
+
+ num_vbias_pins = ret;
+ ret = device_property_read_u32_array(dev, "adi,vbias-pins",
+ vbias_pins,
+ num_vbias_pins);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "Failed to read vbias pins\n");
+ }
+ for (i = 0; i < num_vbias_pins; i++) {
+ if (st->pins_fn[vbias_pins[i]] != AD4170_PIN_UNASIGNED)
+ return dev_err_probe(&st->spi->dev, -EINVAL,
+ "AIN%d already used with fn %u\n",
+ vbias_pins[i], st->pins_fn[i]);
+
+ val |= BIT(vbias_pins[i]);
+ st->pins_fn[vbias_pins[i]] = AD4170_PIN_VBIAS;
+ }
+ return regmap_write(st->regmap, AD4170_V_BIAS_REG, val);
+}
+
+static int ad4170_parse_firmware(struct iio_dev *indio_dev)
+{
+ struct ad4170_state *st = iio_priv(indio_dev);
+ struct device *dev = &st->spi->dev;
+ int ret, i;
+ u8 aux;
+
+ ret = ad4170_clock_select(indio_dev);
+ if (ret < 0)
+ return dev_err_probe(dev, ret, "Failed to setup device clock\n");
+
+ ret = regmap_write(st->regmap, AD4170_CLOCK_CTRL_REG, st->clock_ctrl);
+ if (ret < 0)
+ return ret;
+
+ ret = ad4170_parse_pin_muxing(indio_dev);
+ if (ret < 0)
+ return ret;
+
+ for (i = 0; i < AD4170_NUM_ANALOG_PINS; i++)
+ st->pins_fn[i] = AD4170_PIN_UNASIGNED;
+
+ for (i = 0; i < AD4170_NUM_GPIO_PINS; i++)
+ st->gpio_fn[i] = AD4170_GPIO_UNASIGNED;
+
+ ret = ad4170_parse_exc_current(indio_dev);
+ if (ret)
+ return ret;
+// write to misc reg must be delaied because misc register contains settings
+// that are channel specific.
+
+ ret = ad4170_parse_pw_switch(st, dev);
+ if (ret < 0)
+ return dev_err_probe(dev, ret,
+ "Failed to config power down switches\n");
+
+ ret = ad4170_parse_vbias(st, dev);
+ if (ret < 0)
+ return ret;
+
+ ret = ad4170_parse_channels(indio_dev);
+ if (ret)
+ return ret;
+
+ aux = AD4170_MISC_CHOP_IEXC_OFF;
+ ret = device_property_read_u8(dev, "adi,chop-iexc", &aux);
+ if (!ret) {
+ ret = ad4170_find_table_index(ad4170_iexc_chop_tbl, aux);
+ if (ret < 0)
+ return dev_err_probe(dev, ret,
+ "Invalid adi,chop-iexc config: %u\n",
+ aux);
+ }
+
+ /* Set excitation current chop config to first channel setup config */
+ st->setups[indio_dev->channels[0].address].misc |=
+ FIELD_PREP(AD4170_MISC_CHOP_IEXC_MSK, aux);
+ return 0;
+}
+
+static int ad4170_initial_config(struct iio_dev *indio_dev)
+{
+ struct ad4170_state *st = iio_priv(indio_dev);
+ struct ad4170_chan_info *chan_info;
+ struct iio_chan_spec const *chan;
+ struct ad4170_setup *setup;
+ unsigned int val;
+ unsigned int i;
+ int ret;
+
+ ad4170_fill_sps_tbl(st);
+
+ /* Put ADC in IDLE mode */
+ ret = ad4170_set_mode(st, AD4170_ADC_CTRL_MODE_IDLE);
+ if (ret)
+ return ret;
+
+ /* Setup channels. */
+ for (i = 0; i < indio_dev->num_channels; i++) {
+ chan = &indio_dev->channels[i];
+ chan_info = &st->chans_info[chan->address];
+ setup = &st->setups[chan_info->setup_num];
+
+ ret = regmap_update_bits(st->regmap,
+ AD4170_CHAN_SETUP_REG(chan->address),
+ AD4170_CHANNEL_SETUP_SETUP_MSK,
+ FIELD_PREP(AD4170_CHANNEL_SETUP_SETUP_MSK,
+ chan_info->setup_num));
+ if (ret)
+ return ret;
+
+ setup->gain = AD4170_GAIN_REG_DEFAULT;
+ ret = ad4170_write_setup(st, chan_info->setup_num, setup);
+ if (ret)
+ return ret;
+
+ val = FIELD_PREP(AD4170_CHANNEL_MAPN_AINP_MSK, chan->channel) |
+ FIELD_PREP(AD4170_CHANNEL_MAPN_AINM_MSK, chan->channel2);
+
+ ret = regmap_write(st->regmap, AD4170_CHAN_MAP_REG(i), val);
+ if (ret < 0)
+ return ret;
+
+ ret = ad4170_set_channel_freq(st, chan->address,
+ AD4170_MAX_SAMP_RATE, 0);
+ if (ret)
+ return ret;
+
+ ret = ad4170_fill_scale_tbl(indio_dev, i);
+ if (ret)
+ return ret;
+ }
+
+ ret = regmap_write(st->regmap, AD4170_CHANNEL_EN_REG, 0);
+ if (ret < 0)
+ return ret;
+
+ /*
+ * Configure channels to share the same data output register, i.e. data
+ * can be read from the same register address regardless of channel
+ * number.
+ */
+ ret = regmap_update_bits(st->regmap, AD4170_ADC_CTRL_REG,
+ AD4170_ADC_CTRL_MULTI_DATA_REG_SEL_MSK,
+ AD4170_ADC_CTRL_MULTI_DATA_REG_SEL_MSK);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static const struct iio_trigger_ops ad4170_trigger_ops = {
+ .validate_device = iio_trigger_validate_own_device,
+};
+
+static irqreturn_t ad4170_interrupt(int irq, void *dev_id)
+{
+ struct iio_dev *indio_dev = dev_id;
+ struct ad4170_state *st = iio_priv(indio_dev);
+
+ if (iio_buffer_enabled(indio_dev))
+ iio_trigger_poll(st->trig);
+ else
+ complete(&st->completion);
+
+ return IRQ_HANDLED;
+};
+
+static void ad4170_prepare_message(struct ad4170_state *st)
+{
+ /*
+ * Continuous data register read is enabled on buffer postenable so
+ * no instruction phase is needed meaning we don't need to send the
+ * register address to read data. Transfer only needs the read buffer.
+ */
+ st->xfer.rx_buf = &st->reg_read_rx_buf;
+ st->xfer.bits_per_word = ad4170_channel_template.scan_type.storagebits;
+ st->xfer.len = BITS_TO_BYTES(ad4170_channel_template.scan_type.storagebits);
+
+ spi_message_init_with_transfers(&st->msg, &st->xfer, 1);
+}
+
+static int ad4170_buffer_postenable(struct iio_dev *indio_dev)
+{
+ struct ad4170_state *st = iio_priv(indio_dev);
+ int ret;
+
+ ret = ad4170_set_mode(st, AD4170_ADC_CTRL_MODE_CONT);
+ if (ret < 0)
+ return ret;
+
+ ret = regmap_update_bits(st->regmap, AD4170_ADC_CTRL_REG,
+ AD4170_REG_CTRL_CONT_READ_MSK,
+ FIELD_PREP(AD4170_REG_CTRL_CONT_READ_MSK,
+ AD4170_ADC_CTRL_CONT_READ_ENABLE));
+
+ if (ret < 0)
+ return ret;
+
+ return spi_optimize_message(st->spi, &st->msg);
+}
+
+static int ad4170_buffer_predisable(struct iio_dev *indio_dev)
+{
+ struct ad4170_state *st = iio_priv(indio_dev);
+ int ret, i;
+
+ spi_unoptimize_message(&st->msg);
+
+ for (i = 0; i < indio_dev->num_channels; i++) {
+ ret = ad4170_set_channel_enable(st, i, false);
+ if (ret)
+ return ret;
+ }
+
+ ret = regmap_update_bits(st->regmap, AD4170_ADC_CTRL_REG,
+ AD4170_REG_CTRL_CONT_READ_MSK,
+ FIELD_PREP(AD4170_REG_CTRL_CONT_READ_MSK,
+ AD4170_ADC_CTRL_CONT_READ_DISABLE));
+ if (ret < 0)
+ return ret;
+
+ return ad4170_set_mode(st, AD4170_ADC_CTRL_MODE_IDLE);
+}
+
+static const struct iio_buffer_setup_ops ad4170_buffer_ops = {
+ .postenable = ad4170_buffer_postenable,
+ .predisable = ad4170_buffer_predisable,
+};
+
+static irqreturn_t ad4170_trigger_handler(int irq, void *p)
+{
+ struct iio_poll_func *pf = p;
+ struct iio_dev *indio_dev = pf->indio_dev;
+ struct ad4170_state *st = iio_priv(indio_dev);
+ int ret, i = 0;
+ int scan_index;
+
+ for_each_set_bit(scan_index, indio_dev->active_scan_mask,
+ indio_dev->masklength) {
+ /* Read register data */
+ ret = regmap_read(st->regmap, AD4170_DATA_24b_REG, &st->data[i]);
+ if (ret)
+ goto out;
+ i++;
+ }
+
+ iio_push_to_buffers_with_timestamp(indio_dev, &st->data,
+ iio_get_time_ns(indio_dev));
+out:
+ iio_trigger_notify_done(indio_dev->trig);
+ return IRQ_HANDLED;
+}
+
+static int ad4170_triggered_buffer_setup(struct iio_dev *indio_dev)
+{
+ struct ad4170_state *st = iio_priv(indio_dev);
+ int ret;
+
+ indio_dev->modes |= INDIO_BUFFER_TRIGGERED;
+
+ st->trig = devm_iio_trigger_alloc(indio_dev->dev.parent, "%s-trig%d",
+ indio_dev->name,
+ iio_device_id(indio_dev));
+ if (!st->trig)
+ return -ENOMEM;
+
+ st->trig->ops = &ad4170_trigger_ops;
+ st->trig->dev.parent = indio_dev->dev.parent;
+
+ iio_trigger_set_drvdata(st->trig, indio_dev);
+ ret = devm_iio_trigger_register(indio_dev->dev.parent, st->trig);
+ if (ret)
+ return ret;
+
+ indio_dev->trig = iio_trigger_get(st->trig);
+
+ ret = request_irq(st->spi->irq,
+ &ad4170_interrupt,
+ IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+ indio_dev->name, indio_dev);
+ if (ret)
+ return ret;
+
+ return devm_iio_triggered_buffer_setup(indio_dev->dev.parent, indio_dev,
+ &iio_pollfunc_store_time,
+ &ad4170_trigger_handler,
+ &ad4170_buffer_ops);
+}
+
+static int ad4170_probe(struct spi_device *spi)
+{
+ struct device *dev = &spi->dev;
+ struct iio_dev *indio_dev;
+ struct ad4170_state *st;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ st = iio_priv(indio_dev);
+ devm_mutex_init(dev, &st->lock);
+
+ indio_dev->name = AD4170_NAME;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->info = &ad4170_info;
+
+ st->spi = spi;
+ st->regmap = devm_regmap_init(dev, NULL, st, &ad4170_regmap_config);
+
+ st->supplies[AD4170_AVDD_SUP].supply = "avdd";
+ st->supplies[AD4170_AVSS_SUP].supply = "avss";
+ st->supplies[AD4170_IOVDD_SUP].supply = "iovdd";
+ st->supplies[AD4170_REFIN1P_SUP].supply = "refin1p";
+ st->supplies[AD4170_REFIN1N_SUP].supply = "refin1n";
+ st->supplies[AD4170_REFIN2P_SUP].supply = "refin2p";
+ st->supplies[AD4170_REFIN2N_SUP].supply = "refin2n";
+
+ /*
+ * If a regulator is not available, it will be set to a dummy regulator.
+ * Each channel reference is checked with regulator_get_voltage() before
+ * setting attributes so if any channel uses a dummy supply the driver
+ * probe will fail.
+ */
+ ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(st->supplies),
+ st->supplies);
+ if (ret)
+ return dev_err_probe(dev, ret, "Failed to get supplies\n");
+
+ ret = regulator_bulk_enable(ARRAY_SIZE(st->supplies), st->supplies);
+ if (ret)
+ return dev_err_probe(dev, ret, "Failed to enable supplies\n");
+
+ ret = devm_add_action_or_reset(dev, ad4170_disable_supplies, st);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "Failed to add supplies disable action\n");
+
+ ret = ad4170_soft_reset(st);
+ if (ret)
+ return ret;
+
+ ret = ad4170_parse_firmware(indio_dev);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "Failed to parse firmware\n");
+
+ ret = ad4170_initial_config(indio_dev);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "Failed to setup device\n");
+
+ init_completion(&st->completion);
+
+ ret = ad4170_triggered_buffer_setup(indio_dev);
+ if (ret)
+ return dev_err_probe(dev, ret, "Failed to setup read buffer\n");
+
+ ad4170_prepare_message(st);
+
+ return devm_iio_device_register(dev, indio_dev);
+}
+
+static const struct of_device_id ad4170_of_match[] = {
+ {
+ .compatible = "adi,ad4170",
+ },
+ { }
+};
+MODULE_DEVICE_TABLE(of, ad4170_of_match);
+
+static struct spi_driver ad4170_driver = {
+ .driver = {
+ .name = AD4170_NAME,
+ .of_match_table = ad4170_of_match,
+ },
+ .probe = ad4170_probe,
+};
+module_spi_driver(ad4170_driver);
+
+MODULE_AUTHOR("Ana-Maria Cusco <ana-maria.cusco@analog.com>");
+MODULE_AUTHOR("Marcelo Schmitt <marcelo.schmitt@analog.com>");
+MODULE_DESCRIPTION("Analog Devices AD4170 SPI driver");
+MODULE_LICENSE("GPL");
new file mode 100644
@@ -0,0 +1,316 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * AD4170 ADC driver
+ *
+ * Copyright 2024 Analog Devices Inc.
+ */
+
+#include <dt-bindings/iio/adc/adi,ad4170.h>
+
+#define AD4170_NAME "ad4170"
+
+#define AD4170_READ_MASK BIT(14)
+/* AD4170 registers */
+#define AD4170_INTERFACE_CONFIG_A_REG 0x00
+#define AD4170_STATUS_REG 0x14
+#define AD4170_DATA_24b_REG 0x1c
+#define AD4170_PIN_MUXING_REG 0x68
+#define AD4170_CLOCK_CTRL_REG 0x6A
+#define AD4170_POWER_DOWN_SW_REG 0x6e
+#define AD4170_ADC_CTRL_REG 0x70
+#define AD4170_CHANNEL_EN_REG 0x78
+#define AD4170_CHAN_SETUP_REG(x) (0x80 + 4 * (x))
+#define AD4170_CHAN_MAP_REG(x) (0x82 + 4 * (x))
+#define AD4170_MISC_REG(x) (0xc0 + 14 * (x))
+#define AD4170_AFE_REG(x) (0xc2 + 14 * (x))
+#define AD4170_FILTER_REG(x) (0xc4 + 14 * (x))
+#define AD4170_FILTER_FS_REG(x) (0xc6 + 14 * (x))
+#define AD4170_OFFSET_REG(x) (0xc8 + 14 * (x))
+#define AD4170_GAIN_REG(x) (0xcb + 14 * (x))
+#define AD4170_V_BIAS_REG 0x134
+#define AD4170_CURRENT_SRC_REG(x) (0x138 + 2 * (x))
+
+/* AD4170_REG_INTERFACE_CONFIG_A */
+#define AD4170_SW_RESET_MSK (BIT(7) | BIT(0))
+#define AD4170_IFACE_CONFIG_ADDR_ASCENSION_MSK BIT(5)
+#define AD4170_RESET_SLEEP_US 1000
+#define AD4170_INT_REF_2_5V 2500000
+
+/* AD4170_REG_PIN_MUXING */
+#define AD4170_PIN_MUXING_DIG_AUX2_CTRL_MSK GENMASK(7, 6)
+#define AD4170_PIN_MUXING_DIG_AUX1_CTRL_MSK GENMASK(5, 4)
+#define AD4170_PIN_MUXING_SYNC_CTRL_MSK GENMASK(3, 2)
+
+/* AD4170_REG_CLOCK_CTRL */
+#define AD4170_INT_FREQ_16MHZ 16000000
+#define AD4170_EXT_FREQ_MHZ_MIN 1000000
+#define AD4170_EXT_FREQ_MHZ_MAX 17000000
+#define AD4170_CLOCK_CTRL_CLOCKSEL_MSK GENMASK(1, 0)
+
+#define AD4170_INTERNAL_OSC 0x0
+#define AD4170_INTERNAL_OSC_OUTPUT 0x1
+#define AD4170_EXTERNAL_OSC 0x2
+#define AD4170_EXTERNAL_XTAL 0x3
+
+/* AD4170_REG_POWER_DOWN_SW */
+#define AD4170_POWER_DOWN_SW_PDSW1_MSK BIT(1)
+#define AD4170_POWER_DOWN_SW_PDSW0_MSK BIT(0)
+
+/* AD4170_REG_ADC_CTRL */
+#define AD4170_ADC_CTRL_MULTI_DATA_REG_SEL_MSK BIT(7)
+#define AD4170_REG_CTRL_CONT_READ_MSK GENMASK(5, 4)
+#define AD4170_REG_CTRL_MODE_MSK GENMASK(3, 0)
+
+/* AD4170_REG_CHANNEL_EN */
+#define AD4170_CHANNEL_EN(ch) BIT(ch)
+
+/* AD4170_REG_ADC_CHANNEL_SETUP */
+#define AD4170_CHANNEL_SETUP_SETUP_MSK GENMASK(2, 0)
+
+/* AD4170_REG_ADC_CHANNEL_MAP */
+#define AD4170_CHANNEL_MAPN_AINP_MSK GENMASK(12, 8)
+#define AD4170_CHANNEL_MAPN_AINM_MSK GENMASK(4, 0)
+
+/* AD4170_REG_ADC_SETUPS_MISC */
+#define AD4170_MISC_CHOP_IEXC_MSK GENMASK(15, 14)
+#define AD4170_MISC_CHOP_ADC_MSK GENMASK(9, 8)
+#define AD4170_MISC_BURNOUT_MSK GENMASK(1, 0)
+
+/* AD4170_REG_ADC_SETUPS_AFE */
+#define AD4170_AFE_REF_BUF_M_MSK GENMASK(11, 10)
+#define AD4170_AFE_REF_BUF_P_MSK GENMASK(9, 8)
+#define AD4170_AFE_REF_SELECT_MSK GENMASK(6, 5)
+#define AD4170_AFE_BIPOLAR_MSK BIT(4)
+#define AD4170_AFE_PGA_GAIN_MSK GENMASK(3, 0)
+
+/* AD4170_REG_ADC_SETUPS_FILTER */
+#define AD4170_SETUPS_POST_FILTER_SEL_MSK GENMASK(7, 4)
+#define AD4170_SETUPS_FILTER_TYPE_MSK GENMASK(3, 0)
+
+/* AD4170 REG_OFFSET*/
+#define AD4170_OFFSET_MSK GENMASK(23, 0)
+
+/* AD4170 REG_GAIN*/
+#define AD4170_GAIN_MSK GENMASK(23, 0)
+#define AD4170_GAIN_REG_DEFAULT 0x555555
+
+/* AD4170_REG_CURRENT_SOURCE */
+#define AD4170_CURRENT_SRC_I_OUT_PIN_MSK GENMASK(12, 8)
+#define AD4170_CURRENT_SRC_I_OUT_VAL_MSK GENMASK(2, 0)
+
+/* AD4170_REG_FIR_CONTROL */
+#define AD4170_FIR_CONTROL_IIR_MODE_MSK BIT(15)
+
+#define AD4170_MAX_CHANNELS 16
+#define AD4170_MAX_ANALOG_PINS 8
+#define AD4170_MAX_SETUPS 8
+#define AD4170_INVALID_SETUP_SLOT 9
+#define AD4170_NUM_CURRENT_SRC 4
+#define AD4170_MAX_SAMP_RATE 125000
+
+#define AD4170_NUM_ANALOG_PINS 9
+#define AD4170_NUM_GPIO_PINS 4
+
+#define AD4170_DIG_AUX1_DISABLED 0
+#define AD4170_DIG_AUX1_RDY 1
+#define AD4170_DIG_AUX1_SYNC 2
+
+#define AD4170_DIG_AUX2_DISABLED 0
+#define AD4170_DIG_AUX2_LDAC 1
+#define AD4170_DIG_AUX2_SYNC 2
+
+#define AD4170_SYNC_DISABLED 0
+#define AD4170_SYNC_STANDARD 1
+#define AD4170_SYNC_ALTERNATE 2
+
+#define AD4170_I_OUT_0UA 0
+#define AD4170_I_OUT_10UA 10
+#define AD4170_I_OUT_50UA 50
+#define AD4170_I_OUT_100UA 100
+#define AD4170_I_OUT_250UA 250
+#define AD4170_I_OUT_500UA 500
+#define AD4170_I_OUT_1000UA 1000
+#define AD4170_I_OUT_1500UA 1500
+
+#define AD4170_BURNOUT_OFF 0
+#define AD4170_BURNOUT_100NA 100
+#define AD4170_BURNOUT_2000NA 2000
+#define AD4170_BURNOUT_10000NA 10000
+
+#define AD4170_PGA_OPTIONS 10
+
+enum ad4170_pin_function {
+ AD4170_PIN_UNASIGNED,
+ AD4170_PIN_ANALOG_IN,
+ AD4170_PIN_CURRENT_OUT,
+ AD4170_PIN_VBIAS
+};
+
+enum ad4170_gpio_function {
+ AD4170_GPIO_UNASIGNED,
+ AD4170_GPIO_PW_DOW_SWITCH,
+ AD4170_GPIO_AC_EXCITATION,
+ AD4170_GPIO_OUTPUT,
+ AD4170_GPIO_CHANNEL,
+};
+
+#define AD4170_ADC_CTRL_CONT_READ_DISABLE 0
+#define AD4170_ADC_CTRL_CONT_READ_ENABLE 1
+//#define AD4170_ADC_CTRL_CONT_READ_TRANSMIT 2
+
+#define AD4170_ADC_CTRL_MODE_CONT 0
+#define AD4170_ADC_CTRL_MODE_SINGLE 4
+#define AD4170_ADC_CTRL_MODE_IDLE 7
+
+/**
+ * @enum ad4170_ref_buf
+ * @brief REFIN Buffer Enable.
+ */
+enum ad4170_ref_buf {
+ /** Pre-charge Buffer. */
+ AD4170_REF_BUF_PRE,
+ /** Full Buffer.*/
+ AD4170_REF_BUF_FULL,
+ /** Bypass */
+ AD4170_REF_BUF_BYPASS
+};
+
+/**
+ * @enum ad4170_filter_type
+ * @brief Filter Mode for Sinc-Based Filters.
+ */
+enum ad4170_filter_type {
+ AD4170_SINC5_AVG,
+ AD4170_SINC5,
+ AD4170_SINC3,
+};
+
+/* ADC Register Lengths */
+static const unsigned int ad4170_reg_size[] = {
+ [AD4170_INTERFACE_CONFIG_A_REG] = 1,
+ [AD4170_STATUS_REG] = 2,
+ [AD4170_DATA_24b_REG] = 3,
+ [AD4170_PIN_MUXING_REG] = 2,
+ [AD4170_CLOCK_CTRL_REG] = 2,
+ [AD4170_POWER_DOWN_SW_REG] = 2,
+ [AD4170_ADC_CTRL_REG] = 2,
+ [AD4170_CHANNEL_EN_REG] = 2,
+ /*
+ * CHANNEL_SETUP and CHANNEL_MAP register are all 2 byte size each and
+ * their addresses are interleaved such that we have CHANNEL_SETUP0
+ * address followed by CHANNEL_MAP0 address, followed by CHANNEL_SETUP1,
+ * and so on until CHANNEL_MAP15.
+ * Thus, initialize the register size for them only once.
+ */
+ [AD4170_CHAN_SETUP_REG(0) ... AD4170_CHAN_MAP_REG(AD4170_MAX_CHANNELS - 1)] = 2,
+ /*
+ * MISC, AFE, FILTER, FILTER_FS, OFFSET, and GAIN register addresses are
+ * also interleaved but MISC, AFE, FILTER, FILTER_FS, OFFSET are 16-bit
+ * while OFFSET, GAIN are 24-bit registers so we can't init them all to
+ * the same size.
+ */
+ /* Init MISC register size */
+ [AD4170_MISC_REG(0)] = 2,
+ [AD4170_MISC_REG(1)] = 2,
+ [AD4170_MISC_REG(2)] = 2,
+ [AD4170_MISC_REG(3)] = 2,
+ [AD4170_MISC_REG(4)] = 2,
+ [AD4170_MISC_REG(5)] = 2,
+ [AD4170_MISC_REG(6)] = 2,
+ [AD4170_MISC_REG(7)] = 2,
+ /* Init AFE register size */
+ [AD4170_AFE_REG(0)] = 2,
+ [AD4170_AFE_REG(1)] = 2,
+ [AD4170_AFE_REG(2)] = 2,
+ [AD4170_AFE_REG(3)] = 2,
+ [AD4170_AFE_REG(4)] = 2,
+ [AD4170_AFE_REG(5)] = 2,
+ [AD4170_AFE_REG(6)] = 2,
+ [AD4170_AFE_REG(7)] = 2,
+ /* Init FILTER register size */
+ [AD4170_FILTER_REG(0)] = 2,
+ [AD4170_FILTER_REG(1)] = 2,
+ [AD4170_FILTER_REG(2)] = 2,
+ [AD4170_FILTER_REG(3)] = 2,
+ [AD4170_FILTER_REG(4)] = 2,
+ [AD4170_FILTER_REG(5)] = 2,
+ [AD4170_FILTER_REG(6)] = 2,
+ [AD4170_FILTER_REG(7)] = 2,
+ /* Init FILTER_FS register size */
+ [AD4170_FILTER_FS_REG(0)] = 2,
+ [AD4170_FILTER_FS_REG(1)] = 2,
+ [AD4170_FILTER_FS_REG(2)] = 2,
+ [AD4170_FILTER_FS_REG(3)] = 2,
+ [AD4170_FILTER_FS_REG(4)] = 2,
+ [AD4170_FILTER_FS_REG(5)] = 2,
+ [AD4170_FILTER_FS_REG(6)] = 2,
+ [AD4170_FILTER_FS_REG(7)] = 2,
+ /* Init OFFSET register size */
+ [AD4170_OFFSET_REG(0)] = 3,
+ [AD4170_OFFSET_REG(1)] = 3,
+ [AD4170_OFFSET_REG(2)] = 3,
+ [AD4170_OFFSET_REG(3)] = 3,
+ [AD4170_OFFSET_REG(4)] = 3,
+ [AD4170_OFFSET_REG(5)] = 3,
+ [AD4170_OFFSET_REG(6)] = 3,
+ [AD4170_OFFSET_REG(7)] = 3,
+ /* Init GAIN register size */
+ [AD4170_GAIN_REG(0)] = 3,
+ [AD4170_GAIN_REG(1)] = 3,
+ [AD4170_GAIN_REG(2)] = 3,
+ [AD4170_GAIN_REG(3)] = 3,
+ [AD4170_GAIN_REG(4)] = 3,
+ [AD4170_GAIN_REG(5)] = 3,
+ [AD4170_GAIN_REG(6)] = 3,
+ [AD4170_GAIN_REG(7)] = 3,
+ [AD4170_V_BIAS_REG] = 2,
+ [AD4170_CURRENT_SRC_REG(0) ... AD4170_CURRENT_SRC_REG(AD4170_NUM_CURRENT_SRC - 1)] = 2,
+};
+
+static const unsigned int ad4170_chop_adc_tbl[] = {
+ AD4170_MISC_CHOP_ADC_OFF,
+ AD4170_MISC_CHOP_ADC_MUX,
+ AD4170_MISC_CHOP_ADC_ACX_4PIN,
+ AD4170_MISC_CHOP_ADC_ACX_2PIN
+};
+
+static const unsigned int ad4170_iexc_chop_tbl[] = {
+ AD4170_MISC_CHOP_IEXC_OFF,
+ AD4170_MISC_CHOP_IEXC_AB,
+ AD4170_MISC_CHOP_IEXC_CD,
+ AD4170_MISC_CHOP_IEXC_ABCD,
+};
+
+static const unsigned int ad4170_iout_pin_tbl[] = {
+ AD4170_CURRENT_IOUT_AIN0,
+ AD4170_CURRENT_IOUT_AIN1,
+ AD4170_CURRENT_IOUT_AIN2,
+ AD4170_CURRENT_IOUT_AIN3,
+ AD4170_CURRENT_IOUT_AIN4,
+ AD4170_CURRENT_IOUT_AIN5,
+ AD4170_CURRENT_IOUT_AIN6,
+ AD4170_CURRENT_IOUT_AIN7,
+ AD4170_CURRENT_IOUT_AIN8,
+ AD4170_CURRENT_IOUT_GPIO0,
+ AD4170_CURRENT_IOUT_GPIO1,
+ AD4170_CURRENT_IOUT_GPIO2,
+ AD4170_CURRENT_IOUT_GPIO3,
+};
+
+static const unsigned int ad4170_iout_current_ua_tbl[] = {
+ AD4170_I_OUT_0UA,
+ AD4170_I_OUT_10UA,
+ AD4170_I_OUT_50UA,
+ AD4170_I_OUT_100UA,
+ AD4170_I_OUT_250UA,
+ AD4170_I_OUT_500UA,
+ AD4170_I_OUT_1000UA,
+ AD4170_I_OUT_1500UA,
+};
+
+static const unsigned int ad4170_burnout_current_na_tbl[] = {
+ AD4170_BURNOUT_OFF,
+ AD4170_BURNOUT_100NA,
+ AD4170_BURNOUT_2000NA,
+ AD4170_BURNOUT_10000NA,
+};