iio: adc: ad7173: add AD7173 driver
authorDumitru Ceclan <mitrutzceclan@gmail.com>
Wed, 28 Feb 2024 11:06:20 +0000 (13:06 +0200)
committerJonathan Cameron <Jonathan.Cameron@huawei.com>
Mon, 25 Mar 2024 20:10:11 +0000 (20:10 +0000)
The AD7173 family offer a complete integrated Sigma-Delta ADC solution
which can be used in high precision, low noise single channel
applications or higher speed multiplexed applications. The Sigma-Delta
ADC is intended primarily for measurement of signals close to DC but also
delivers outstanding performance with input bandwidths out to ~10kHz.

Reviewed-by: Andy Shevchenko <andy@kernel.org>
Reviewed-by: Michael Walle <michael@walle.cc> # for gpio-regmap
Signed-off-by: Dumitru Ceclan <mitrutzceclan@gmail.com>
Reviewed-by: Nuno Sa <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20240228110622.25114-3-mitrutzceclan@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
drivers/iio/adc/Kconfig
drivers/iio/adc/Makefile
drivers/iio/adc/ad7173.c [new file with mode: 0644]

index 0d9282fa67f59ca403c89f601233cc7bb30d6568..91286ab83bd0954655991686c9d44fe88da48442 100644 (file)
@@ -70,6 +70,23 @@ config AD7124
          To compile this driver as a module, choose M here: the module will be
          called ad7124.
 
+config AD7173
+       tristate "Analog Devices AD7173 driver"
+       depends on SPI_MASTER
+       select AD_SIGMA_DELTA
+       select GPIO_REGMAP if GPIOLIB
+       select REGMAP_SPI if GPIOLIB
+       help
+         Say yes here to build support for Analog Devices AD7173 and similar ADC
+         Currently supported models:
+          - AD7172-2
+          - AD7173-8
+          - AD7175-2
+          - AD7176-2
+
+         To compile this driver as a module, choose M here: the module will be
+         called ad7173.
+
 config AD7192
        tristate "Analog Devices AD7190 AD7192 AD7193 AD7195 ADC driver"
        depends on SPI
index b3c434722364a2b735025e914eed1b59b5d70125..717e964afed97119fbd7a68aba6d457b865bfb95 100644 (file)
@@ -11,6 +11,7 @@ obj-$(CONFIG_AD7091R) += ad7091r-base.o
 obj-$(CONFIG_AD7091R5) += ad7091r5.o
 obj-$(CONFIG_AD7091R8) += ad7091r8.o
 obj-$(CONFIG_AD7124) += ad7124.o
+obj-$(CONFIG_AD7173) += ad7173.o
 obj-$(CONFIG_AD7192) += ad7192.o
 obj-$(CONFIG_AD7266) += ad7266.o
 obj-$(CONFIG_AD7280) += ad7280a.o
diff --git a/drivers/iio/adc/ad7173.c b/drivers/iio/adc/ad7173.c
new file mode 100644 (file)
index 0000000..b42fbe2
--- /dev/null
@@ -0,0 +1,1116 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * AD7172-2/AD7173-8/AD7175-2/AD7176-2 SPI ADC driver
+ * Copyright (C) 2015, 2024 Analog Devices, Inc.
+ */
+
+#include <linux/array_size.h>
+#include <linux/bitfield.h>
+#include <linux/bitmap.h>
+#include <linux/container_of.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/gpio/regmap.h>
+#include <linux/idr.h>
+#include <linux/interrupt.h>
+#include <linux/math64.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/property.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+#include <linux/slab.h>
+#include <linux/spi/spi.h>
+#include <linux/types.h>
+#include <linux/units.h>
+
+#include <linux/iio/buffer.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+
+#include <linux/iio/adc/ad_sigma_delta.h>
+
+#define AD7173_REG_COMMS               0x00
+#define AD7173_REG_ADC_MODE            0x01
+#define AD7173_REG_INTERFACE_MODE      0x02
+#define AD7173_REG_CRC                 0x03
+#define AD7173_REG_DATA                        0x04
+#define AD7173_REG_GPIO                        0x06
+#define AD7173_REG_ID                  0x07
+#define AD7173_REG_CH(x)               (0x10 + (x))
+#define AD7173_REG_SETUP(x)            (0x20 + (x))
+#define AD7173_REG_FILTER(x)           (0x28 + (x))
+#define AD7173_REG_OFFSET(x)           (0x30 + (x))
+#define AD7173_REG_GAIN(x)             (0x38 + (x))
+
+#define AD7173_RESET_LENGTH            BITS_TO_BYTES(64)
+
+#define AD7173_CH_ENABLE               BIT(15)
+#define AD7173_CH_SETUP_SEL_MASK       GENMASK(14, 12)
+#define AD7173_CH_SETUP_AINPOS_MASK    GENMASK(9, 5)
+#define AD7173_CH_SETUP_AINNEG_MASK    GENMASK(4, 0)
+
+#define AD7173_CH_ADDRESS(pos, neg) \
+       (FIELD_PREP(AD7173_CH_SETUP_AINPOS_MASK, pos) | \
+        FIELD_PREP(AD7173_CH_SETUP_AINNEG_MASK, neg))
+#define AD7173_AIN_TEMP_POS    17
+#define AD7173_AIN_TEMP_NEG    18
+
+#define AD7172_ID                      0x00d0
+#define AD7173_ID                      0x30d0
+#define AD7175_ID                      0x0cd0
+#define AD7176_ID                      0x0c90
+#define AD7173_ID_MASK                 GENMASK(15, 4)
+
+#define AD7173_ADC_MODE_REF_EN         BIT(15)
+#define AD7173_ADC_MODE_SING_CYC       BIT(13)
+#define AD7173_ADC_MODE_MODE_MASK      GENMASK(6, 4)
+#define AD7173_ADC_MODE_CLOCKSEL_MASK  GENMASK(3, 2)
+#define AD7173_ADC_MODE_CLOCKSEL_INT           0x0
+#define AD7173_ADC_MODE_CLOCKSEL_INT_OUTPUT    0x1
+#define AD7173_ADC_MODE_CLOCKSEL_EXT           0x2
+#define AD7173_ADC_MODE_CLOCKSEL_XTAL          0x3
+
+#define AD7173_GPIO_PDSW       BIT(14)
+#define AD7173_GPIO_OP_EN2_3   BIT(13)
+#define AD7173_GPIO_MUX_IO     BIT(12)
+#define AD7173_GPIO_SYNC_EN    BIT(11)
+#define AD7173_GPIO_ERR_EN     BIT(10)
+#define AD7173_GPIO_ERR_DAT    BIT(9)
+#define AD7173_GPIO_GP_DATA3   BIT(7)
+#define AD7173_GPIO_GP_DATA2   BIT(6)
+#define AD7173_GPIO_IP_EN1     BIT(5)
+#define AD7173_GPIO_IP_EN0     BIT(4)
+#define AD7173_GPIO_OP_EN1     BIT(3)
+#define AD7173_GPIO_OP_EN0     BIT(2)
+#define AD7173_GPIO_GP_DATA1   BIT(1)
+#define AD7173_GPIO_GP_DATA0   BIT(0)
+
+#define AD7173_GPO12_DATA(x)   BIT((x) + 0)
+#define AD7173_GPO23_DATA(x)   BIT((x) + 4)
+#define AD7173_GPO_DATA(x)     ((x) < 2 ? AD7173_GPO12_DATA(x) : AD7173_GPO23_DATA(x))
+
+#define AD7173_INTERFACE_DATA_STAT     BIT(6)
+#define AD7173_INTERFACE_DATA_STAT_EN(x) \
+       FIELD_PREP(AD7173_INTERFACE_DATA_STAT, x)
+
+#define AD7173_SETUP_BIPOLAR           BIT(12)
+#define AD7173_SETUP_AREF_BUF_MASK     GENMASK(11, 10)
+#define AD7173_SETUP_AIN_BUF_MASK      GENMASK(9, 8)
+
+#define AD7173_SETUP_REF_SEL_MASK      GENMASK(5, 4)
+#define AD7173_SETUP_REF_SEL_AVDD1_AVSS        0x3
+#define AD7173_SETUP_REF_SEL_INT_REF   0x2
+#define AD7173_SETUP_REF_SEL_EXT_REF2  0x1
+#define AD7173_SETUP_REF_SEL_EXT_REF   0x0
+#define AD7173_VOLTAGE_INT_REF_uV      2500000
+#define AD7173_TEMP_SENSIIVITY_uV_per_C        477
+
+#define AD7173_FILTER_ODR0_MASK                GENMASK(5, 0)
+#define AD7173_MAX_CONFIGS             8
+
+enum ad7173_ids {
+       ID_AD7172_2,
+       ID_AD7173_8,
+       ID_AD7175_2,
+       ID_AD7176_2,
+};
+
+struct ad7173_device_info {
+       const unsigned int *sinc5_data_rates;
+       unsigned int num_sinc5_data_rates;
+       unsigned int num_channels;
+       unsigned int num_configs;
+       unsigned int num_inputs;
+       unsigned int clock;
+       unsigned int id;
+       char *name;
+       bool has_temp;
+       u8 num_gpios;
+};
+
+struct ad7173_channel_config {
+       u8 cfg_slot;
+       bool live;
+
+       /* Following fields are used to compare equality. */
+       struct_group(config_props,
+               bool bipolar;
+               bool input_buf;
+               u8 odr;
+               u8 ref_sel;
+       );
+};
+
+struct ad7173_channel {
+       unsigned int chan_reg;
+       unsigned int ain;
+       struct ad7173_channel_config cfg;
+};
+
+struct ad7173_state {
+       struct ad_sigma_delta sd;
+       const struct ad7173_device_info *info;
+       struct ad7173_channel *channels;
+       struct regulator_bulk_data regulators[3];
+       unsigned int adc_mode;
+       unsigned int interface_mode;
+       unsigned int num_channels;
+       struct ida cfg_slots_status;
+       unsigned long long config_usage_counter;
+       unsigned long long *config_cnts;
+       struct clk *ext_clk;
+       struct clk_hw int_clk_hw;
+#if IS_ENABLED(CONFIG_GPIOLIB)
+       struct regmap *reg_gpiocon_regmap;
+       struct gpio_regmap *gpio_regmap;
+#endif
+};
+
+static const unsigned int ad7173_sinc5_data_rates[] = {
+       6211000, 6211000, 6211000, 6211000, 6211000, 6211000, 5181000, 4444000, /*  0-7  */
+       3115000, 2597000, 1007000, 503800,  381000,  200300,  100500,  59520,   /*  8-15 */
+       49680,   20010,   16333,   10000,   5000,    2500,    1250,             /* 16-22 */
+};
+
+static const unsigned int ad7175_sinc5_data_rates[] = {
+       50000000, 41667000, 31250000, 27778000, /*  0-3  */
+       20833000, 17857000, 12500000, 10000000, /*  4-7  */
+       5000000,  2500000,  1000000,  500000,   /*  8-11 */
+       397500,   200000,   100000,   59920,    /* 12-15 */
+       49960,    20000,    16666,    10000,    /* 16-19 */
+       5000,                                   /* 20    */
+};
+
+static const struct ad7173_device_info ad7173_device_info[] = {
+       [ID_AD7172_2] = {
+               .name = "ad7172-2",
+               .id = AD7172_ID,
+               .num_inputs = 5,
+               .num_channels = 4,
+               .num_configs = 4,
+               .num_gpios = 2,
+               .has_temp = true,
+               .clock = 2 * HZ_PER_MHZ,
+               .sinc5_data_rates = ad7173_sinc5_data_rates,
+               .num_sinc5_data_rates = ARRAY_SIZE(ad7173_sinc5_data_rates),
+       },
+       [ID_AD7173_8] = {
+               .name = "ad7173-8",
+               .id = AD7173_ID,
+               .num_inputs = 17,
+               .num_channels = 16,
+               .num_configs = 8,
+               .num_gpios = 4,
+               .has_temp = true,
+               .clock = 2 * HZ_PER_MHZ,
+               .sinc5_data_rates = ad7173_sinc5_data_rates,
+               .num_sinc5_data_rates = ARRAY_SIZE(ad7173_sinc5_data_rates),
+       },
+       [ID_AD7175_2] = {
+               .name = "ad7175-2",
+               .id = AD7175_ID,
+               .num_inputs = 5,
+               .num_channels = 4,
+               .num_configs = 4,
+               .num_gpios = 2,
+               .has_temp = true,
+               .clock = 16 * HZ_PER_MHZ,
+               .sinc5_data_rates = ad7175_sinc5_data_rates,
+               .num_sinc5_data_rates = ARRAY_SIZE(ad7175_sinc5_data_rates),
+       },
+       [ID_AD7176_2] = {
+               .name = "ad7176-2",
+               .id = AD7176_ID,
+               .num_inputs = 5,
+               .num_channels = 4,
+               .num_configs = 4,
+               .num_gpios = 2,
+               .has_temp = false,
+               .clock = 16 * HZ_PER_MHZ,
+               .sinc5_data_rates = ad7175_sinc5_data_rates,
+               .num_sinc5_data_rates = ARRAY_SIZE(ad7175_sinc5_data_rates),
+       },
+};
+
+static const char *const ad7173_ref_sel_str[] = {
+       [AD7173_SETUP_REF_SEL_EXT_REF]    = "vref",
+       [AD7173_SETUP_REF_SEL_EXT_REF2]   = "vref2",
+       [AD7173_SETUP_REF_SEL_INT_REF]    = "refout-avss",
+       [AD7173_SETUP_REF_SEL_AVDD1_AVSS] = "avdd",
+};
+
+static const char *const ad7173_clk_sel[] = {
+       "ext-clk", "xtal"
+};
+
+#if IS_ENABLED(CONFIG_GPIOLIB)
+
+static const struct regmap_range ad7173_range_gpio[] = {
+       regmap_reg_range(AD7173_REG_GPIO, AD7173_REG_GPIO),
+};
+
+static const struct regmap_access_table ad7173_access_table = {
+       .yes_ranges = ad7173_range_gpio,
+       .n_yes_ranges = ARRAY_SIZE(ad7173_range_gpio),
+};
+
+static const struct regmap_config ad7173_regmap_config = {
+       .reg_bits = 8,
+       .val_bits = 16,
+       .rd_table = &ad7173_access_table,
+       .wr_table = &ad7173_access_table,
+       .read_flag_mask = BIT(6),
+};
+
+static int ad7173_mask_xlate(struct gpio_regmap *gpio, unsigned int base,
+                            unsigned int offset, unsigned int *reg,
+                            unsigned int *mask)
+{
+       *mask = AD7173_GPO_DATA(offset);
+       *reg = base;
+       return 0;
+}
+
+static void ad7173_gpio_disable(void *data)
+{
+       struct ad7173_state *st = data;
+       unsigned int mask;
+
+       mask = AD7173_GPIO_OP_EN0 | AD7173_GPIO_OP_EN1 | AD7173_GPIO_OP_EN2_3;
+       regmap_update_bits(st->reg_gpiocon_regmap, AD7173_REG_GPIO, mask, ~mask);
+}
+
+static int ad7173_gpio_init(struct ad7173_state *st)
+{
+       struct gpio_regmap_config gpio_regmap = {};
+       struct device *dev = &st->sd.spi->dev;
+       unsigned int mask;
+       int ret;
+
+       st->reg_gpiocon_regmap = devm_regmap_init_spi(st->sd.spi, &ad7173_regmap_config);
+       ret = PTR_ERR_OR_ZERO(st->reg_gpiocon_regmap);
+       if (ret)
+               return dev_err_probe(dev, ret, "Unable to init regmap\n");
+
+       mask = AD7173_GPIO_OP_EN0 | AD7173_GPIO_OP_EN1 | AD7173_GPIO_OP_EN2_3;
+       regmap_update_bits(st->reg_gpiocon_regmap, AD7173_REG_GPIO, mask, mask);
+
+       ret = devm_add_action_or_reset(dev, ad7173_gpio_disable, st);
+       if (ret)
+               return ret;
+
+       gpio_regmap.parent = dev;
+       gpio_regmap.regmap = st->reg_gpiocon_regmap;
+       gpio_regmap.ngpio = st->info->num_gpios;
+       gpio_regmap.reg_set_base = AD7173_REG_GPIO;
+       gpio_regmap.reg_mask_xlate = ad7173_mask_xlate;
+
+       st->gpio_regmap = devm_gpio_regmap_register(dev, &gpio_regmap);
+       ret = PTR_ERR_OR_ZERO(st->gpio_regmap);
+       if (ret)
+               return dev_err_probe(dev, ret, "Unable to init gpio-regmap\n");
+
+       return 0;
+}
+#else
+static int ad7173_gpio_init(struct ad7173_state *st)
+{
+       return 0;
+}
+#endif /* CONFIG_GPIOLIB */
+
+static struct ad7173_state *ad_sigma_delta_to_ad7173(struct ad_sigma_delta *sd)
+{
+       return container_of(sd, struct ad7173_state, sd);
+}
+
+static struct ad7173_state *clk_hw_to_ad7173(struct clk_hw *hw)
+{
+       return container_of(hw, struct ad7173_state, int_clk_hw);
+}
+
+static void ad7173_ida_destroy(void *data)
+{
+       struct ad7173_state *st = data;
+
+       ida_destroy(&st->cfg_slots_status);
+}
+
+static void ad7173_reset_usage_cnts(struct ad7173_state *st)
+{
+       memset64(st->config_cnts, 0, st->info->num_configs);
+       st->config_usage_counter = 0;
+}
+
+static struct ad7173_channel_config *
+ad7173_find_live_config(struct ad7173_state *st, struct ad7173_channel_config *cfg)
+{
+       struct ad7173_channel_config *cfg_aux;
+       ptrdiff_t cmp_size;
+       int i;
+
+       cmp_size = sizeof_field(struct ad7173_channel_config, config_props);
+       for (i = 0; i < st->num_channels; i++) {
+               cfg_aux = &st->channels[i].cfg;
+
+               if (cfg_aux->live &&
+                   !memcmp(&cfg->config_props, &cfg_aux->config_props, cmp_size))
+                       return cfg_aux;
+       }
+       return NULL;
+}
+
+/* Could be replaced with a generic LRU implementation */
+static int ad7173_free_config_slot_lru(struct ad7173_state *st)
+{
+       int i, lru_position = 0;
+
+       for (i = 1; i < st->info->num_configs; i++)
+               if (st->config_cnts[i] < st->config_cnts[lru_position])
+                       lru_position = i;
+
+       for (i = 0; i < st->num_channels; i++)
+               if (st->channels[i].cfg.cfg_slot == lru_position)
+                       st->channels[i].cfg.live = false;
+
+       ida_free(&st->cfg_slots_status, lru_position);
+       return ida_alloc(&st->cfg_slots_status, GFP_KERNEL);
+}
+
+/* Could be replaced with a generic LRU implementation */
+static int ad7173_load_config(struct ad7173_state *st,
+                             struct ad7173_channel_config *cfg)
+{
+       unsigned int config;
+       int free_cfg_slot, ret;
+
+       free_cfg_slot = ida_alloc_range(&st->cfg_slots_status, 0,
+                                       st->info->num_configs - 1, GFP_KERNEL);
+       if (free_cfg_slot < 0)
+               free_cfg_slot = ad7173_free_config_slot_lru(st);
+
+       cfg->cfg_slot = free_cfg_slot;
+       config = FIELD_PREP(AD7173_SETUP_REF_SEL_MASK, cfg->ref_sel);
+
+       if (cfg->bipolar)
+               config |= AD7173_SETUP_BIPOLAR;
+
+       if (cfg->input_buf)
+               config |= AD7173_SETUP_AIN_BUF_MASK;
+
+       ret = ad_sd_write_reg(&st->sd, AD7173_REG_SETUP(free_cfg_slot), 2, config);
+       if (ret)
+               return ret;
+
+       return ad_sd_write_reg(&st->sd, AD7173_REG_FILTER(free_cfg_slot), 2,
+                              AD7173_FILTER_ODR0_MASK & cfg->odr);
+}
+
+static int ad7173_config_channel(struct ad7173_state *st, int addr)
+{
+       struct ad7173_channel_config *cfg = &st->channels[addr].cfg;
+       struct ad7173_channel_config *live_cfg;
+       int ret;
+
+       if (!cfg->live) {
+               live_cfg = ad7173_find_live_config(st, cfg);
+               if (live_cfg) {
+                       cfg->cfg_slot = live_cfg->cfg_slot;
+               } else {
+                       ret = ad7173_load_config(st, cfg);
+                       if (ret)
+                               return ret;
+                       cfg->live = true;
+               }
+       }
+
+       if (st->config_usage_counter == U64_MAX)
+               ad7173_reset_usage_cnts(st);
+
+       st->config_usage_counter++;
+       st->config_cnts[cfg->cfg_slot] = st->config_usage_counter;
+
+       return 0;
+}
+
+static int ad7173_set_channel(struct ad_sigma_delta *sd, unsigned int channel)
+{
+       struct ad7173_state *st = ad_sigma_delta_to_ad7173(sd);
+       unsigned int val;
+       int ret;
+
+       ret = ad7173_config_channel(st, channel);
+       if (ret)
+               return ret;
+
+       val = AD7173_CH_ENABLE |
+             FIELD_PREP(AD7173_CH_SETUP_SEL_MASK, st->channels[channel].cfg.cfg_slot) |
+             st->channels[channel].ain;
+
+       return ad_sd_write_reg(&st->sd, AD7173_REG_CH(channel), 2, val);
+}
+
+static int ad7173_set_mode(struct ad_sigma_delta *sd,
+                          enum ad_sigma_delta_mode mode)
+{
+       struct ad7173_state *st = ad_sigma_delta_to_ad7173(sd);
+
+       st->adc_mode &= ~AD7173_ADC_MODE_MODE_MASK;
+       st->adc_mode |= FIELD_PREP(AD7173_ADC_MODE_MODE_MASK, mode);
+
+       return ad_sd_write_reg(&st->sd, AD7173_REG_ADC_MODE, 2, st->adc_mode);
+}
+
+static int ad7173_append_status(struct ad_sigma_delta *sd, bool append)
+{
+       struct ad7173_state *st = ad_sigma_delta_to_ad7173(sd);
+       unsigned int interface_mode = st->interface_mode;
+       int ret;
+
+       interface_mode |= AD7173_INTERFACE_DATA_STAT_EN(append);
+       ret = ad_sd_write_reg(&st->sd, AD7173_REG_INTERFACE_MODE, 2, interface_mode);
+       if (ret)
+               return ret;
+
+       st->interface_mode = interface_mode;
+
+       return 0;
+}
+
+static int ad7173_disable_all(struct ad_sigma_delta *sd)
+{
+       struct ad7173_state *st = ad_sigma_delta_to_ad7173(sd);
+       int ret;
+       int i;
+
+       for (i = 0; i < st->num_channels; i++) {
+               ret = ad_sd_write_reg(sd, AD7173_REG_CH(i), 2, 0);
+               if (ret < 0)
+                       return ret;
+       }
+
+       return 0;
+}
+
+static struct ad_sigma_delta_info ad7173_sigma_delta_info = {
+       .set_channel = ad7173_set_channel,
+       .append_status = ad7173_append_status,
+       .disable_all = ad7173_disable_all,
+       .set_mode = ad7173_set_mode,
+       .has_registers = true,
+       .addr_shift = 0,
+       .read_mask = BIT(6),
+       .status_ch_mask = GENMASK(3, 0),
+       .data_reg = AD7173_REG_DATA,
+};
+
+static int ad7173_setup(struct iio_dev *indio_dev)
+{
+       struct ad7173_state *st = iio_priv(indio_dev);
+       struct device *dev = &st->sd.spi->dev;
+       u8 buf[AD7173_RESET_LENGTH];
+       unsigned int id;
+       int ret;
+
+       /* reset the serial interface */
+       memset(buf, 0xff, AD7173_RESET_LENGTH);
+       ret = spi_write_then_read(st->sd.spi, buf, sizeof(buf), NULL, 0);
+       if (ret < 0)
+               return ret;
+
+       /* datasheet recommends a delay of at least 500us after reset */
+       fsleep(500);
+
+       ret = ad_sd_read_reg(&st->sd, AD7173_REG_ID, 2, &id);
+       if (ret)
+               return ret;
+
+       id &= AD7173_ID_MASK;
+       if (id != st->info->id)
+               dev_warn(dev, "Unexpected device id: 0x%04X, expected: 0x%04X\n",
+                        id, st->info->id);
+
+       st->adc_mode |= AD7173_ADC_MODE_SING_CYC;
+       st->interface_mode = 0x0;
+
+       st->config_usage_counter = 0;
+       st->config_cnts = devm_kcalloc(dev, st->info->num_configs,
+                                      sizeof(*st->config_cnts), GFP_KERNEL);
+       if (!st->config_cnts)
+               return -ENOMEM;
+
+       /* All channels are enabled by default after a reset */
+       return ad7173_disable_all(&st->sd);
+}
+
+static unsigned int ad7173_get_ref_voltage_milli(struct ad7173_state *st,
+                                                u8 reference_select)
+{
+       int vref;
+
+       switch (reference_select) {
+       case AD7173_SETUP_REF_SEL_EXT_REF:
+               vref = regulator_get_voltage(st->regulators[0].consumer);
+               break;
+
+       case AD7173_SETUP_REF_SEL_EXT_REF2:
+               vref = regulator_get_voltage(st->regulators[1].consumer);
+               break;
+
+       case AD7173_SETUP_REF_SEL_INT_REF:
+               vref = AD7173_VOLTAGE_INT_REF_uV;
+               break;
+
+       case AD7173_SETUP_REF_SEL_AVDD1_AVSS:
+               vref = regulator_get_voltage(st->regulators[2].consumer);
+               break;
+
+       default:
+               return -EINVAL;
+       }
+
+       if (vref < 0)
+               return vref;
+
+       return vref / (MICRO / MILLI);
+}
+
+static int ad7173_read_raw(struct iio_dev *indio_dev,
+                          struct iio_chan_spec const *chan,
+                          int *val, int *val2, long info)
+{
+       struct ad7173_state *st = iio_priv(indio_dev);
+       struct ad7173_channel *ch = &st->channels[chan->address];
+       unsigned int reg;
+       u64 temp;
+       int ret;
+
+       switch (info) {
+       case IIO_CHAN_INFO_RAW:
+               ret = ad_sigma_delta_single_conversion(indio_dev, chan, val);
+               if (ret < 0)
+                       return ret;
+
+               /* disable channel after single conversion */
+               ret = ad_sd_write_reg(&st->sd, AD7173_REG_CH(chan->address), 2, 0);
+               if (ret < 0)
+                       return ret;
+
+               return IIO_VAL_INT;
+       case IIO_CHAN_INFO_SCALE:
+               if (chan->type == IIO_TEMP) {
+                       temp = AD7173_VOLTAGE_INT_REF_uV * MILLI;
+                       temp /= AD7173_TEMP_SENSIIVITY_uV_per_C;
+                       *val = temp;
+                       *val2 = chan->scan_type.realbits;
+               } else {
+                       *val = ad7173_get_ref_voltage_milli(st, ch->cfg.ref_sel);
+                       *val2 = chan->scan_type.realbits - !!(ch->cfg.bipolar);
+               }
+               return IIO_VAL_FRACTIONAL_LOG2;
+       case IIO_CHAN_INFO_OFFSET:
+               if (chan->type == IIO_TEMP) {
+                       /* 0 Kelvin -> raw sample */
+                       temp   = -ABSOLUTE_ZERO_MILLICELSIUS;
+                       temp  *= AD7173_TEMP_SENSIIVITY_uV_per_C;
+                       temp <<= chan->scan_type.realbits;
+                       temp   = DIV_U64_ROUND_CLOSEST(temp,
+                                                      AD7173_VOLTAGE_INT_REF_uV *
+                                                      MILLI);
+                       *val   = -temp;
+               } else {
+                       *val = -BIT(chan->scan_type.realbits - 1);
+               }
+               return IIO_VAL_INT;
+       case IIO_CHAN_INFO_SAMP_FREQ:
+               reg = st->channels[chan->address].cfg.odr;
+
+               *val = st->info->sinc5_data_rates[reg] / MILLI;
+               *val2 = (st->info->sinc5_data_rates[reg] % MILLI) * (MICRO / MILLI);
+
+               return IIO_VAL_INT_PLUS_MICRO;
+       default:
+               return -EINVAL;
+       }
+}
+
+static int ad7173_write_raw(struct iio_dev *indio_dev,
+                           struct iio_chan_spec const *chan,
+                           int val, int val2, long info)
+{
+       struct ad7173_state *st = iio_priv(indio_dev);
+       struct ad7173_channel_config *cfg;
+       unsigned int freq, i, reg;
+       int ret;
+
+       ret = iio_device_claim_direct_mode(indio_dev);
+       if (ret)
+               return ret;
+
+       switch (info) {
+       case IIO_CHAN_INFO_SAMP_FREQ:
+               freq = val * MILLI + val2 / MILLI;
+               for (i = 0; i < st->info->num_sinc5_data_rates - 1; i++)
+                       if (freq >= st->info->sinc5_data_rates[i])
+                               break;
+
+               cfg = &st->channels[chan->address].cfg;
+               cfg->odr = i;
+
+               if (!cfg->live)
+                       break;
+
+               ret = ad_sd_read_reg(&st->sd, AD7173_REG_FILTER(cfg->cfg_slot), 2, &reg);
+               if (ret)
+                       break;
+               reg &= ~AD7173_FILTER_ODR0_MASK;
+               reg |= FIELD_PREP(AD7173_FILTER_ODR0_MASK, i);
+               ret = ad_sd_write_reg(&st->sd, AD7173_REG_FILTER(cfg->cfg_slot), 2, reg);
+               break;
+
+       default:
+               ret = -EINVAL;
+               break;
+       }
+
+       iio_device_release_direct_mode(indio_dev);
+       return ret;
+}
+
+static int ad7173_update_scan_mode(struct iio_dev *indio_dev,
+                                  const unsigned long *scan_mask)
+{
+       struct ad7173_state *st = iio_priv(indio_dev);
+       int i, ret;
+
+       for (i = 0; i < indio_dev->num_channels; i++) {
+               if (test_bit(i, scan_mask))
+                       ret = ad7173_set_channel(&st->sd, i);
+               else
+                       ret = ad_sd_write_reg(&st->sd, AD7173_REG_CH(i), 2, 0);
+               if (ret < 0)
+                       return ret;
+       }
+
+       return 0;
+}
+
+static int ad7173_debug_reg_access(struct iio_dev *indio_dev, unsigned int reg,
+                                  unsigned int writeval, unsigned int *readval)
+{
+       struct ad7173_state *st = iio_priv(indio_dev);
+       u8 reg_size;
+
+       if (reg == AD7173_REG_COMMS)
+               reg_size = 1;
+       else if (reg == AD7173_REG_CRC || reg == AD7173_REG_DATA ||
+                reg >= AD7173_REG_OFFSET(0))
+               reg_size = 3;
+       else
+               reg_size = 2;
+
+       if (readval)
+               return ad_sd_read_reg(&st->sd, reg, reg_size, readval);
+
+       return ad_sd_write_reg(&st->sd, reg, reg_size, writeval);
+}
+
+static const struct iio_info ad7173_info = {
+       .read_raw = &ad7173_read_raw,
+       .write_raw = &ad7173_write_raw,
+       .debugfs_reg_access = &ad7173_debug_reg_access,
+       .validate_trigger = ad_sd_validate_trigger,
+       .update_scan_mode = ad7173_update_scan_mode,
+};
+
+static const struct iio_chan_spec ad7173_channel_template = {
+       .type = IIO_VOLTAGE,
+       .indexed = 1,
+       .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+               BIT(IIO_CHAN_INFO_SCALE),
+       .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
+       .scan_type = {
+               .sign = 'u',
+               .realbits = 24,
+               .storagebits = 32,
+               .endianness = IIO_BE,
+       },
+};
+
+static const struct iio_chan_spec ad7173_temp_iio_channel_template = {
+       .type = IIO_TEMP,
+       .indexed = 1,
+       .channel = AD7173_AIN_TEMP_POS,
+       .channel2 = AD7173_AIN_TEMP_NEG,
+       .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+               BIT(IIO_CHAN_INFO_SCALE) | BIT(IIO_CHAN_INFO_OFFSET),
+       .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
+       .scan_type = {
+               .sign = 'u',
+               .realbits = 24,
+               .storagebits = 32,
+               .endianness = IIO_BE,
+       },
+};
+
+static void ad7173_disable_regulators(void *data)
+{
+       struct ad7173_state *st = data;
+
+       regulator_bulk_disable(ARRAY_SIZE(st->regulators), st->regulators);
+}
+
+static void ad7173_clk_disable_unprepare(void *clk)
+{
+       clk_disable_unprepare(clk);
+}
+
+static unsigned long ad7173_sel_clk(struct ad7173_state *st,
+                                   unsigned int clk_sel)
+{
+       int ret;
+
+       st->adc_mode &= !AD7173_ADC_MODE_CLOCKSEL_MASK;
+       st->adc_mode |= FIELD_PREP(AD7173_ADC_MODE_CLOCKSEL_MASK, clk_sel);
+       ret = ad_sd_write_reg(&st->sd, AD7173_REG_ADC_MODE, 0x2, st->adc_mode);
+
+       return ret;
+}
+
+static unsigned long ad7173_clk_recalc_rate(struct clk_hw *hw,
+                                           unsigned long parent_rate)
+{
+       struct ad7173_state *st = clk_hw_to_ad7173(hw);
+
+       return st->info->clock / HZ_PER_KHZ;
+}
+
+static int ad7173_clk_output_is_enabled(struct clk_hw *hw)
+{
+       struct ad7173_state *st = clk_hw_to_ad7173(hw);
+       u32 clk_sel;
+
+       clk_sel = FIELD_GET(AD7173_ADC_MODE_CLOCKSEL_MASK, st->adc_mode);
+       return clk_sel == AD7173_ADC_MODE_CLOCKSEL_INT_OUTPUT;
+}
+
+static int ad7173_clk_output_prepare(struct clk_hw *hw)
+{
+       struct ad7173_state *st = clk_hw_to_ad7173(hw);
+
+       return ad7173_sel_clk(st, AD7173_ADC_MODE_CLOCKSEL_INT_OUTPUT);
+}
+
+static void ad7173_clk_output_unprepare(struct clk_hw *hw)
+{
+       struct ad7173_state *st = clk_hw_to_ad7173(hw);
+
+       ad7173_sel_clk(st, AD7173_ADC_MODE_CLOCKSEL_INT);
+}
+
+static const struct clk_ops ad7173_int_clk_ops = {
+       .recalc_rate = ad7173_clk_recalc_rate,
+       .is_enabled = ad7173_clk_output_is_enabled,
+       .prepare = ad7173_clk_output_prepare,
+       .unprepare = ad7173_clk_output_unprepare,
+};
+
+static int ad7173_register_clk_provider(struct iio_dev *indio_dev)
+{
+       struct ad7173_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 = &ad7173_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 ad7173_fw_parse_channel_config(struct iio_dev *indio_dev)
+{
+       struct ad7173_channel *chans_st_arr, *chan_st_priv;
+       struct ad7173_state *st = iio_priv(indio_dev);
+       struct device *dev = indio_dev->dev.parent;
+       struct iio_chan_spec *chan_arr, *chan;
+       unsigned int ain[2], chan_index = 0;
+       struct fwnode_handle *child;
+       int ref_sel, ret;
+
+       chan_arr = devm_kcalloc(dev, sizeof(*indio_dev->channels),
+                               st->num_channels, GFP_KERNEL);
+       if (!chan_arr)
+               return -ENOMEM;
+
+       chans_st_arr = devm_kcalloc(dev, st->num_channels, sizeof(*st->channels),
+                                   GFP_KERNEL);
+       if (!chans_st_arr)
+               return -ENOMEM;
+
+       indio_dev->channels = chan_arr;
+       st->channels = chans_st_arr;
+
+       if (st->info->has_temp) {
+               chan_arr[chan_index] = ad7173_temp_iio_channel_template;
+               chan_st_priv = &chans_st_arr[chan_index];
+               chan_st_priv->ain =
+                       AD7173_CH_ADDRESS(chan_arr[chan_index].channel,
+                                         chan_arr[chan_index].channel2);
+               chan_st_priv->cfg.bipolar = false;
+               chan_st_priv->cfg.input_buf = true;
+               chan_st_priv->cfg.ref_sel = AD7173_SETUP_REF_SEL_INT_REF;
+               st->adc_mode |= AD7173_ADC_MODE_REF_EN;
+
+               chan_index++;
+       }
+
+       device_for_each_child_node(dev, child) {
+               chan = &chan_arr[chan_index];
+               chan_st_priv = &chans_st_arr[chan_index];
+               ret = fwnode_property_read_u32_array(child, "diff-channels",
+                                                    ain, ARRAY_SIZE(ain));
+               if (ret) {
+                       fwnode_handle_put(child);
+                       return ret;
+               }
+
+               if (ain[0] >= st->info->num_inputs ||
+                   ain[1] >= st->info->num_inputs) {
+                       fwnode_handle_put(child);
+                       return dev_err_probe(dev, -EINVAL,
+                               "Input pin number out of range for pair (%d %d).\n",
+                               ain[0], ain[1]);
+               }
+
+               ret = fwnode_property_match_property_string(child,
+                                                           "adi,reference-select",
+                                                           ad7173_ref_sel_str,
+                                                           ARRAY_SIZE(ad7173_ref_sel_str));
+               if (ret < 0)
+                       ref_sel = AD7173_SETUP_REF_SEL_INT_REF;
+               else
+                       ref_sel = ret;
+
+               if (ref_sel == AD7173_SETUP_REF_SEL_EXT_REF2 &&
+                   st->info->id != AD7173_ID) {
+                       fwnode_handle_put(child);
+                       return dev_err_probe(dev, -EINVAL,
+                               "External reference 2 is only available on ad7173-8\n");
+               }
+
+               ret = ad7173_get_ref_voltage_milli(st, ref_sel);
+               if (ret < 0) {
+                       fwnode_handle_put(child);
+                       return dev_err_probe(dev, ret,
+                                            "Cannot use reference %u\n", ref_sel);
+               }
+               if (ref_sel == AD7173_SETUP_REF_SEL_INT_REF)
+                       st->adc_mode |= AD7173_ADC_MODE_REF_EN;
+               chan_st_priv->cfg.ref_sel = ref_sel;
+
+               *chan = ad7173_channel_template;
+               chan->address = chan_index;
+               chan->scan_index = chan_index;
+               chan->channel = ain[0];
+               chan->channel2 = ain[1];
+               chan->differential = true;
+
+               chan_st_priv->ain = AD7173_CH_ADDRESS(ain[0], ain[1]);
+               chan_st_priv->chan_reg = chan_index;
+               chan_st_priv->cfg.input_buf = true;
+               chan_st_priv->cfg.odr = 0;
+
+               chan_st_priv->cfg.bipolar = fwnode_property_read_bool(child, "bipolar");
+               if (chan_st_priv->cfg.bipolar)
+                       chan->info_mask_separate |= BIT(IIO_CHAN_INFO_OFFSET);
+
+               chan_index++;
+       }
+       return 0;
+}
+
+static int ad7173_fw_parse_device_config(struct iio_dev *indio_dev)
+{
+       struct ad7173_state *st = iio_priv(indio_dev);
+       struct device *dev = indio_dev->dev.parent;
+       unsigned int num_channels;
+       int ret;
+
+       st->regulators[0].supply = ad7173_ref_sel_str[AD7173_SETUP_REF_SEL_EXT_REF];
+       st->regulators[1].supply = ad7173_ref_sel_str[AD7173_SETUP_REF_SEL_EXT_REF2];
+       st->regulators[2].supply = ad7173_ref_sel_str[AD7173_SETUP_REF_SEL_AVDD1_AVSS];
+
+       /*
+        * 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->regulators),
+                                     st->regulators);
+       if (ret)
+               return dev_err_probe(dev, ret, "Failed to get regulators\n");
+
+       ret = regulator_bulk_enable(ARRAY_SIZE(st->regulators), st->regulators);
+       if (ret)
+               return dev_err_probe(dev, ret, "Failed to enable regulators\n");
+
+       ret = devm_add_action_or_reset(dev, ad7173_disable_regulators, st);
+       if (ret)
+               return dev_err_probe(dev, ret,
+                                    "Failed to add regulators disable action\n");
+
+       ret = device_property_match_property_string(dev, "clock-names",
+                                                   ad7173_clk_sel,
+                                                   ARRAY_SIZE(ad7173_clk_sel));
+       if (ret < 0) {
+               st->adc_mode |= FIELD_PREP(AD7173_ADC_MODE_CLOCKSEL_MASK,
+                                          AD7173_ADC_MODE_CLOCKSEL_INT);
+               ad7173_register_clk_provider(indio_dev);
+       } else {
+               st->adc_mode |= FIELD_PREP(AD7173_ADC_MODE_CLOCKSEL_MASK,
+                                          AD7173_ADC_MODE_CLOCKSEL_EXT + ret);
+               st->ext_clk = devm_clk_get(dev, ad7173_clk_sel[ret]);
+               if (IS_ERR(st->ext_clk))
+                       return dev_err_probe(dev, PTR_ERR(st->ext_clk),
+                                            "Failed to get external clock\n");
+
+               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, ad7173_clk_disable_unprepare,
+                                              st->ext_clk);
+               if (ret)
+                       return ret;
+       }
+
+       ret = fwnode_irq_get_byname(dev_fwnode(dev), "rdy");
+       if (ret < 0)
+               return dev_err_probe(dev, ret, "Interrupt 'rdy' is required\n");
+
+       ad7173_sigma_delta_info.irq_line = ret;
+
+       num_channels = device_get_child_node_count(dev);
+
+       if (st->info->has_temp)
+               num_channels++;
+
+       if (num_channels == 0)
+               return dev_err_probe(dev, -ENODATA, "No channels specified\n");
+       indio_dev->num_channels = num_channels;
+       st->num_channels = num_channels;
+
+       return ad7173_fw_parse_channel_config(indio_dev);
+}
+
+static int ad7173_probe(struct spi_device *spi)
+{
+       struct device *dev = &spi->dev;
+       struct ad7173_state *st;
+       struct iio_dev *indio_dev;
+       int ret;
+
+       indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
+       if (!indio_dev)
+               return -ENOMEM;
+
+       st = iio_priv(indio_dev);
+       st->info = spi_get_device_match_data(spi);
+       if (!st->info)
+               return -ENODEV;
+
+       ida_init(&st->cfg_slots_status);
+       ret = devm_add_action_or_reset(dev, ad7173_ida_destroy, st);
+       if (ret)
+               return ret;
+
+       indio_dev->name = st->info->name;
+       indio_dev->modes = INDIO_DIRECT_MODE;
+       indio_dev->info = &ad7173_info;
+
+       spi->mode = SPI_MODE_3;
+       spi_setup(spi);
+
+       ad7173_sigma_delta_info.num_slots = st->info->num_configs;
+       ret = ad_sd_init(&st->sd, indio_dev, spi, &ad7173_sigma_delta_info);
+       if (ret)
+               return ret;
+
+       ret = ad7173_fw_parse_device_config(indio_dev);
+       if (ret)
+               return ret;
+
+       ret = devm_ad_sd_setup_buffer_and_trigger(dev, indio_dev);
+       if (ret)
+               return ret;
+
+       ret = ad7173_setup(indio_dev);
+       if (ret)
+               return ret;
+
+       ret = devm_iio_device_register(dev, indio_dev);
+       if (ret)
+               return ret;
+
+       if (IS_ENABLED(CONFIG_GPIOLIB))
+               return ad7173_gpio_init(st);
+
+       return 0;
+}
+
+static const struct of_device_id ad7173_of_match[] = {
+       { .compatible = "adi,ad7172-2",
+         .data = &ad7173_device_info[ID_AD7172_2]},
+       { .compatible = "adi,ad7173-8",
+         .data = &ad7173_device_info[ID_AD7173_8]},
+       { .compatible = "adi,ad7175-2",
+         .data = &ad7173_device_info[ID_AD7175_2]},
+       { .compatible = "adi,ad7176-2",
+         .data = &ad7173_device_info[ID_AD7176_2]},
+       { }
+};
+MODULE_DEVICE_TABLE(of, ad7173_of_match);
+
+static const struct spi_device_id ad7173_id_table[] = {
+       { "ad7172-2", (kernel_ulong_t)&ad7173_device_info[ID_AD7172_2]},
+       { "ad7173-8", (kernel_ulong_t)&ad7173_device_info[ID_AD7173_8]},
+       { "ad7175-2", (kernel_ulong_t)&ad7173_device_info[ID_AD7175_2]},
+       { "ad7176-2", (kernel_ulong_t)&ad7173_device_info[ID_AD7176_2]},
+       { }
+};
+MODULE_DEVICE_TABLE(spi, ad7173_id_table);
+
+static struct spi_driver ad7173_driver = {
+       .driver = {
+               .name   = "ad7173",
+               .of_match_table = ad7173_of_match,
+       },
+       .probe          = ad7173_probe,
+       .id_table       = ad7173_id_table,
+};
+module_spi_driver(ad7173_driver);
+
+MODULE_IMPORT_NS(IIO_AD_SIGMA_DELTA);
+MODULE_AUTHOR("Lars-Peter Clausen <lars@metafo.de>");
+MODULE_AUTHOR("Dumitru Ceclan <dumitru.ceclan@analog.com>");
+MODULE_DESCRIPTION("Analog Devices AD7172/AD7173/AD7175/AD7176 ADC driver");
+MODULE_LICENSE("GPL");