From: Dumitru Ceclan <dumitru.ceclan@analog.com>

Add support for AD4111/AD4112/AD4114/AD4115/AD4116.

The AD411X family encompasses a series of low power, low noise, 24-bit,
sigma-delta analog-to-digital converters that offer a versatile range of
specifications.

This family of ADCs integrates an analog front end suitable for processing
both fully differential and single-ended, bipolar voltage inputs
addressing a wide array of industrial and instrumentation requirements.

- All ADCs have inputs with a precision voltage divider with a division
  ratio of 10.
- AD4116 has 5 low level inputs without a voltage divider.
- AD4111 and AD4112 support current inputs (0 mA to 20 mA) using a 50ohm
  shunt resistor.

Signed-off-by: Dumitru Ceclan <dumitru.ceclan@analog.com>
---
 drivers/iio/adc/ad7173.c | 327 ++++++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 297 insertions(+), 30 deletions(-)

diff --git a/drivers/iio/adc/ad7173.c b/drivers/iio/adc/ad7173.c
index 106a50dbabd4..328685ce25e0 100644
--- a/drivers/iio/adc/ad7173.c
+++ b/drivers/iio/adc/ad7173.c
@@ -1,8 +1,9 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * AD717x family SPI ADC driver
+ * AD717x and AD411x family SPI ADC driver
  *
  * Supported devices:
+ *  AD4111/AD4112/AD4114/AD4115/AD4116
  *  AD7172-2/AD7172-4/AD7173-8/AD7175-2
  *  AD7175-8/AD7176-2/AD7177-2
  *
@@ -75,7 +76,9 @@
 #define AD7176_ID			0x0c90
 #define AD7175_2_ID			0x0cd0
 #define AD7172_4_ID			0x2050
-#define AD7173_ID			0x30d0
+#define AD7173_AD4111_AD4112_AD4114_ID	0x30d0
+#define AD4116_ID			0x34d0
+#define AD4115_ID			0x38d0
 #define AD7175_8_ID			0x3cd0
 #define AD7177_ID			0x4fd0
 #define AD7173_ID_MASK			GENMASK(15, 4)
@@ -106,6 +109,7 @@
 
 #define AD7173_GPO12_DATA(x)	BIT((x) + 0)
 #define AD7173_GPO23_DATA(x)	BIT((x) + 4)
+#define AD4111_GPO01_DATA(x)	BIT((x) + 6)
 #define AD7173_GPO_DATA(x)	((x) < 2 ? AD7173_GPO12_DATA(x) : AD7173_GPO23_DATA(x))
 
 #define AD7173_INTERFACE_DATA_STAT	BIT(6)
@@ -124,11 +128,20 @@
 #define AD7173_VOLTAGE_INT_REF_uV	2500000
 #define AD7173_TEMP_SENSIIVITY_uV_per_C	477
 #define AD7177_ODR_START_VALUE		0x07
+#define AD4111_SHUNT_RESISTOR_OHM	50
+#define AD4111_DIVIDER_RATIO		10
+#define AD411X_VCOM_INPUT		0X10
+#define AD4111_CURRENT_CHAN_CUTOFF	16
 
 #define AD7173_FILTER_ODR0_MASK		GENMASK(5, 0)
 #define AD7173_MAX_CONFIGS		8
 
 enum ad7173_ids {
+	ID_AD4111,
+	ID_AD4112,
+	ID_AD4114,
+	ID_AD4115,
+	ID_AD4116,
 	ID_AD7172_2,
 	ID_AD7172_4,
 	ID_AD7173_8,
@@ -138,22 +151,43 @@ enum ad7173_ids {
 	ID_AD7177_2,
 };
 
+enum ad4111_current_channels {
+	AD4111_CURRENT_IN0P_IN0N,
+	AD4111_CURRENT_IN1P_IN1N,
+	AD4111_CURRENT_IN2P_IN2N,
+	AD4111_CURRENT_IN3P_IN3N,
+};
+
+enum ad7173_channel_types {
+	AD7173_CHAN_SINGLE_ENDED,
+	AD7173_CHAN_DIFFERENTIAL,
+};
+
 struct ad7173_device_info {
 	const unsigned int *sinc5_data_rates;
 	unsigned int num_sinc5_data_rates;
 	unsigned int odr_start_value;
+	/*
+	 * AD4116 has both inputs with a volage divider and without.
+	 * These inputs cannot be mixed in the channel configuration.
+	 * Does not include the VCOM input.
+	 */
+	unsigned int num_voltage_inputs_with_divider;
 	unsigned int num_channels;
 	unsigned int num_configs;
-	unsigned int num_inputs;
+	unsigned int num_voltage_inputs;
 	unsigned int clock;
 	unsigned int id;
 	char *name;
+	bool has_current_inputs;
+	bool has_vcom_input;
 	bool has_temp;
 	/* ((AVDD1 − AVSS)/5) */
 	bool has_common_input;
 	bool has_input_buf;
 	bool has_int_ref;
 	bool has_ref2;
+	bool higher_gpio_bits;
 	u8 num_gpios;
 };
 
@@ -195,6 +229,24 @@ struct ad7173_state {
 #endif
 };
 
+static unsigned int ad4115_sinc5_data_rates[] = {
+	24845000, 24845000, 20725000, 20725000,	/*  0-3  */
+	15564000, 13841000, 10390000, 10390000,	/*  4-7  */
+	4994000,  2499000,  1000000,  500000,	/*  8-11 */
+	395500,   200000,   100000,   59890,	/* 12-15 */
+	49920,    20000,    16660,    10000,	/* 16-19 */
+	5000,	  2500,     2500,		/* 20-22 */
+};
+
+static unsigned int ad4116_sinc5_data_rates[] = {
+	12422360, 12422360, 12422360, 12422360,	/*  0-3  */
+	10362690, 10362690, 7782100,  6290530,	/*  4-7  */
+	5194800,  2496900,  1007600,  499900,	/*  8-11 */
+	390600,	  200300,   100000,   59750,	/* 12-15 */
+	49840,	  20000,    16650,    10000,	/* 16-19 */
+	5000,	  2500,	    1250,		/* 20-22 */
+};
+
 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 */
@@ -210,14 +262,109 @@ static const unsigned int ad7175_sinc5_data_rates[] = {
 	5000,					/* 20    */
 };
 
+static unsigned int ad4111_current_channel_config[] = {
+	[AD4111_CURRENT_IN0P_IN0N] = 0x1E8,
+	[AD4111_CURRENT_IN1P_IN1N] = 0x1C9,
+	[AD4111_CURRENT_IN2P_IN2N] = 0x1AA,
+	[AD4111_CURRENT_IN3P_IN3N] = 0x18B,
+};
+
 static const struct ad7173_device_info ad7173_device_info[] = {
+	[ID_AD4111] = {
+		.name = "ad4111",
+		.id = AD7173_AD4111_AD4112_AD4114_ID,
+		.num_voltage_inputs_with_divider = 8,
+		.num_channels = 16,
+		.num_configs = 8,
+		.num_voltage_inputs = 8,
+		.num_gpios = 2,
+		.higher_gpio_bits = true,
+		.has_temp = true,
+		.has_vcom_input = true,
+		.has_input_buf = true,
+		.has_current_inputs = true,
+		.has_int_ref = true,
+		.clock = 2 * HZ_PER_MHZ,
+		.sinc5_data_rates = ad7173_sinc5_data_rates,
+		.num_sinc5_data_rates = ARRAY_SIZE(ad7173_sinc5_data_rates),
+	},
+	[ID_AD4112] = {
+		.name = "ad4112",
+		.id = AD7173_AD4111_AD4112_AD4114_ID,
+		.num_voltage_inputs_with_divider = 8,
+		.num_channels = 16,
+		.num_configs = 8,
+		.num_voltage_inputs = 8,
+		.num_gpios = 2,
+		.higher_gpio_bits = true,
+		.has_vcom_input = true,
+		.has_temp = true,
+		.has_input_buf = true,
+		.has_current_inputs = true,
+		.has_int_ref = true,
+		.clock = 2 * HZ_PER_MHZ,
+		.sinc5_data_rates = ad7173_sinc5_data_rates,
+		.num_sinc5_data_rates = ARRAY_SIZE(ad7173_sinc5_data_rates),
+	},
+	[ID_AD4114] = {
+		.name = "ad4114",
+		.id = AD7173_AD4111_AD4112_AD4114_ID,
+		.num_voltage_inputs_with_divider = 16,
+		.num_channels = 16,
+		.num_configs = 8,
+		.num_voltage_inputs = 16,
+		.num_gpios = 4,
+		.higher_gpio_bits = true,
+		.has_vcom_input = true,
+		.has_temp = true,
+		.has_input_buf = true,
+		.has_int_ref = true,
+		.clock = 2 * HZ_PER_MHZ,
+		.sinc5_data_rates = ad7173_sinc5_data_rates,
+		.num_sinc5_data_rates = ARRAY_SIZE(ad7173_sinc5_data_rates),
+	},
+	[ID_AD4115] = {
+		.name = "ad4115",
+		.id = AD4115_ID,
+		.num_voltage_inputs_with_divider = 16,
+		.num_channels = 16,
+		.num_configs = 8,
+		.num_voltage_inputs = 16,
+		.num_gpios = 4,
+		.higher_gpio_bits = true,
+		.has_vcom_input = true,
+		.has_temp = true,
+		.has_input_buf = true,
+		.has_int_ref = true,
+		.clock = 8 * HZ_PER_MHZ,
+		.sinc5_data_rates = ad4115_sinc5_data_rates,
+		.num_sinc5_data_rates = ARRAY_SIZE(ad4115_sinc5_data_rates),
+	},
+	[ID_AD4116] = {
+		.name = "ad4116",
+		.id = AD4116_ID,
+		.num_voltage_inputs_with_divider = 11,
+		.num_channels = 16,
+		.num_configs = 8,
+		.num_voltage_inputs = 16,
+		.num_gpios = 4,
+		.higher_gpio_bits = true,
+		.has_vcom_input = true,
+		.has_temp = true,
+		.has_input_buf = true,
+		.has_int_ref = true,
+		.clock = 4 * HZ_PER_MHZ,
+		.sinc5_data_rates = ad4116_sinc5_data_rates,
+		.num_sinc5_data_rates = ARRAY_SIZE(ad4116_sinc5_data_rates),
+	},
 	[ID_AD7172_2] = {
 		.name = "ad7172-2",
 		.id = AD7172_2_ID,
-		.num_inputs = 5,
+		.num_voltage_inputs = 5,
 		.num_channels = 4,
 		.num_configs = 4,
 		.num_gpios = 2,
+		.higher_gpio_bits = false,
 		.has_temp = true,
 		.has_input_buf = true,
 		.has_int_ref = true,
@@ -229,10 +376,11 @@ static const struct ad7173_device_info ad7173_device_info[] = {
 	[ID_AD7172_4] = {
 		.name = "ad7172-4",
 		.id = AD7172_4_ID,
-		.num_inputs = 9,
+		.num_voltage_inputs = 9,
 		.num_channels = 8,
 		.num_configs = 8,
 		.num_gpios = 4,
+		.higher_gpio_bits = false,
 		.has_temp = false,
 		.has_input_buf = true,
 		.has_ref2 = true,
@@ -243,11 +391,12 @@ static const struct ad7173_device_info ad7173_device_info[] = {
 	},
 	[ID_AD7173_8] = {
 		.name = "ad7173-8",
-		.id = AD7173_ID,
-		.num_inputs = 17,
+		.id = AD7173_AD4111_AD4112_AD4114_ID,
+		.num_voltage_inputs = 17,
 		.num_channels = 16,
 		.num_configs = 8,
 		.num_gpios = 4,
+		.higher_gpio_bits = false,
 		.has_temp = true,
 		.has_input_buf = true,
 		.has_int_ref = true,
@@ -260,10 +409,11 @@ static const struct ad7173_device_info ad7173_device_info[] = {
 	[ID_AD7175_2] = {
 		.name = "ad7175-2",
 		.id = AD7175_2_ID,
-		.num_inputs = 5,
+		.num_voltage_inputs = 5,
 		.num_channels = 4,
 		.num_configs = 4,
 		.num_gpios = 2,
+		.higher_gpio_bits = false,
 		.has_temp = true,
 		.has_input_buf = true,
 		.has_int_ref = true,
@@ -275,10 +425,11 @@ static const struct ad7173_device_info ad7173_device_info[] = {
 	[ID_AD7175_8] = {
 		.name = "ad7175-8",
 		.id = AD7175_8_ID,
-		.num_inputs = 17,
+		.num_voltage_inputs = 17,
 		.num_channels = 16,
 		.num_configs = 8,
 		.num_gpios = 4,
+		.higher_gpio_bits = false,
 		.has_temp = true,
 		.has_input_buf = true,
 		.has_int_ref = true,
@@ -291,10 +442,11 @@ static const struct ad7173_device_info ad7173_device_info[] = {
 	[ID_AD7176_2] = {
 		.name = "ad7176-2",
 		.id = AD7176_ID,
-		.num_inputs = 5,
+		.num_voltage_inputs = 5,
 		.num_channels = 4,
 		.num_configs = 4,
 		.num_gpios = 2,
+		.higher_gpio_bits = false,
 		.has_temp = false,
 		.has_input_buf = false,
 		.has_int_ref = true,
@@ -306,10 +458,11 @@ static const struct ad7173_device_info ad7173_device_info[] = {
 	[ID_AD7177_2] = {
 		.name = "ad7177-2",
 		.id = AD7177_ID,
-		.num_inputs = 5,
+		.num_voltage_inputs = 5,
 		.num_channels = 4,
 		.num_configs = 4,
 		.num_gpios = 2,
+		.higher_gpio_bits = false,
 		.has_temp = true,
 		.has_input_buf = true,
 		.has_int_ref = true,
@@ -328,6 +481,11 @@ static const char *const ad7173_ref_sel_str[] = {
 	[AD7173_SETUP_REF_SEL_AVDD1_AVSS] = "avdd",
 };
 
+static const char *const ad7173_channel_types[] = {
+	[AD7173_CHAN_SINGLE_ENDED] = "single-ended",
+	[AD7173_CHAN_DIFFERENTIAL] = "differential",
+};
+
 static const char *const ad7173_clk_sel[] = {
 	"ext-clk", "xtal"
 };
@@ -360,6 +518,15 @@ static int ad7173_mask_xlate(struct gpio_regmap *gpio, unsigned int base,
 	return 0;
 }
 
+static int ad4111_mask_xlate(struct gpio_regmap *gpio, unsigned int base,
+			     unsigned int offset, unsigned int *reg,
+			     unsigned int *mask)
+{
+	*mask = AD4111_GPO01_DATA(offset);
+	*reg = base;
+	return 0;
+}
+
 static void ad7173_gpio_disable(void *data)
 {
 	struct ad7173_state *st = data;
@@ -392,7 +559,10 @@ static int ad7173_gpio_init(struct ad7173_state *st)
 	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;
+	if (st->info->higher_gpio_bits)
+		gpio_regmap.reg_mask_xlate = ad4111_mask_xlate;
+	else
+		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);
@@ -688,18 +858,33 @@ static int ad7173_read_raw(struct iio_dev *indio_dev,
 
 		return IIO_VAL_INT;
 	case IIO_CHAN_INFO_SCALE:
-		if (chan->type == IIO_TEMP) {
+
+		switch (chan->type) {
+		case IIO_TEMP:
 			temp = AD7173_VOLTAGE_INT_REF_uV * MILLI;
 			temp /= AD7173_TEMP_SENSIIVITY_uV_per_C;
 			*val = temp;
 			*val2 = chan->scan_type.realbits;
-		} else {
+			return IIO_VAL_FRACTIONAL_LOG2;
+		case IIO_VOLTAGE:
 			*val = ad7173_get_ref_voltage_milli(st, ch->cfg.ref_sel);
 			*val2 = chan->scan_type.realbits - !!(ch->cfg.bipolar);
+
+			if (chan->channel < st->info->num_voltage_inputs_with_divider)
+				*val *= AD4111_DIVIDER_RATIO;
+			return IIO_VAL_FRACTIONAL_LOG2;
+		case IIO_CURRENT:
+			*val = ad7173_get_ref_voltage_milli(st, ch->cfg.ref_sel);
+			*val /= AD4111_SHUNT_RESISTOR_OHM;
+			*val2 = chan->scan_type.realbits - (ch->cfg.bipolar ? 1 : 0);
+			return IIO_VAL_FRACTIONAL_LOG2;
+		default:
+			return -EINVAL;
 		}
-		return IIO_VAL_FRACTIONAL_LOG2;
 	case IIO_CHAN_INFO_OFFSET:
-		if (chan->type == IIO_TEMP) {
+
+		switch (chan->type) {
+		case IIO_TEMP:
 			/* 0 Kelvin -> raw sample */
 			temp   = -ABSOLUTE_ZERO_MILLICELSIUS;
 			temp  *= AD7173_TEMP_SENSIIVITY_uV_per_C;
@@ -708,10 +893,14 @@ static int ad7173_read_raw(struct iio_dev *indio_dev,
 						       AD7173_VOLTAGE_INT_REF_uV *
 						       MILLI);
 			*val   = -temp;
-		} else {
+			return IIO_VAL_INT;
+		case IIO_VOLTAGE:
+		case IIO_CURRENT:
 			*val = -BIT(chan->scan_type.realbits - 1);
+			return IIO_VAL_INT;
+		default:
+			return -EINVAL;
 		}
-		return IIO_VAL_INT;
 	case IIO_CHAN_INFO_SAMP_FREQ:
 		reg = st->channels[chan->address].cfg.odr;
 
@@ -919,13 +1108,34 @@ static int ad7173_register_clk_provider(struct iio_dev *indio_dev)
 					   &st->int_clk_hw);
 }
 
+static int ad4111_validate_current_ain(struct ad7173_state *st,
+				       unsigned int ain[2])
+{
+	struct device *dev = &st->sd.spi->dev;
+
+	if (!st->info->has_current_inputs)
+		return dev_err_probe(dev, -EINVAL,
+			"Model %s does not support current channels\n",
+			st->info->name);
+
+	if (ain[0] >= ARRAY_SIZE(ad4111_current_channel_config))
+		return dev_err_probe(dev, -EINVAL,
+			"For current channels single-channel must be <[0-3]>\n");
+
+	return 0;
+}
+
 static int ad7173_validate_voltage_ain_inputs(struct ad7173_state *st,
 					      unsigned int ain[2])
 {
 	struct device *dev = &st->sd.spi->dev;
+	bool ain_selects_normal_input[] = {
+		ain[0] < st->info->num_voltage_inputs,
+		ain[1] < st->info->num_voltage_inputs
+	};
 
 	for (int i = 0; i < 2; i++) {
-		if (ain[i] < st->info->num_inputs)
+		if (ain_selects_normal_input[i])
 			continue;
 
 		if (ain[i] == AD7173_AIN_REF_POS || ain[i] == AD7173_AIN_REF_NEG)
@@ -936,11 +1146,27 @@ static int ad7173_validate_voltage_ain_inputs(struct ad7173_state *st,
 		    st->info->has_common_input)
 			continue;
 
+		if (st->info->has_vcom_input && ain[i] == AD411X_VCOM_INPUT) {
+			if (ain_selects_normal_input[(i + 1) % 2] &&
+			    ain[(i + 1) % 2] >= st->info->num_voltage_inputs_with_divider)
+				return dev_err_probe(dev, -EINVAL,
+					"VCOM must be paired with inputs having divider.\n");
+
+			continue;
+		}
+
 		return dev_err_probe(dev, -EINVAL,
 			"Input pin number out of range for pair (%d %d).\n",
 			ain[0], ain[1]);
 	}
 
+	if ((ain_selects_normal_input[0] && ain_selects_normal_input[1]) &&
+	    ((ain[0] >= st->info->num_voltage_inputs_with_divider) !=
+	     (ain[1] >= st->info->num_voltage_inputs_with_divider)))
+		return dev_err_probe(dev, -EINVAL,
+			"Both inputs must either have a voltage divider or not have: (%d %d).\n",
+			ain[0], ain[1]);
+
 	return 0;
 }
 
@@ -972,7 +1198,7 @@ static int ad7173_fw_parse_channel_config(struct iio_dev *indio_dev)
 	struct device *dev = indio_dev->dev.parent;
 	struct iio_chan_spec *chan_arr, *chan;
 	unsigned int ain[2], chan_index = 0;
-	int ref_sel, ret, num_channels;
+	int ref_sel, ret, is_current_chan, num_channels;
 
 	num_channels = device_get_child_node_count(dev);
 
@@ -1022,12 +1248,23 @@ static int ad7173_fw_parse_channel_config(struct iio_dev *indio_dev)
 		chan_st_priv = &chans_st_arr[chan_index];
 		ret = fwnode_property_read_u32_array(child, "diff-channels",
 						     ain, ARRAY_SIZE(ain));
-		if (ret)
-			return ret;
+		if (ret) {
+			ret = fwnode_property_read_u32_array(child, "single-channel",
+							     ain, 1);
+			if (ret)
+				return ret;
 
-		ret = ad7173_validate_voltage_ain_inputs(st, ain);
-		if (ret)
-			return ret;
+			ret = ad4111_validate_current_ain(st, ain);
+			if (ret)
+				return ret;
+			is_current_chan = true;
+			ain[1] = 0;
+		} else {
+			ret = ad7173_validate_voltage_ain_inputs(st, ain);
+			if (ret)
+				return ret;
+			is_current_chan = false;
+		}
 
 		ret = fwnode_property_match_property_string(child,
 							    "adi,reference-select",
@@ -1051,17 +1288,34 @@ static int ad7173_fw_parse_channel_config(struct iio_dev *indio_dev)
 		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 = st->info->has_input_buf;
 		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);
 
+		ret = fwnode_property_match_property_string(child,
+							    "adi,channel-type",
+							    ad7173_channel_types,
+							    ARRAY_SIZE(ad7173_channel_types));
+		chan->differential = (ret < 0 || ret == AD7173_CHAN_DIFFERENTIAL)
+					? 1 : 0;
+
+
+		if (is_current_chan) {
+			chan->type = IIO_CURRENT;
+			chan->differential = false;
+			ain[1] = FIELD_GET(AD7173_CH_SETUP_AINNEG_MASK,
+					   ad4111_current_channel_config[ain[0]]);
+			ain[0] = FIELD_GET(AD7173_CH_SETUP_AINPOS_MASK,
+					   ad4111_current_channel_config[ain[0]]);
+		} else {
+			chan_st_priv->cfg.input_buf = st->info->has_input_buf;
+		}
+		chan_st_priv->ain = AD7173_CH_ADDRESS(ain[0], ain[1]);
+
 		chan_index++;
 	}
 	return 0;
@@ -1188,6 +1442,14 @@ static int ad7173_probe(struct spi_device *spi)
 }
 
 static const struct of_device_id ad7173_of_match[] = {
+	{ .compatible = "ad4111",
+	  .data = &ad7173_device_info[ID_AD4111]},
+	{ .compatible = "ad4112",
+	  .data = &ad7173_device_info[ID_AD4112]},
+	{ .compatible = "ad4114",
+	  .data = &ad7173_device_info[ID_AD4114]},
+	{ .compatible = "ad4115",
+	  .data = &ad7173_device_info[ID_AD4115]},
 	{ .compatible = "adi,ad7172-2",
 	  .data = &ad7173_device_info[ID_AD7172_2]},
 	{ .compatible = "adi,ad7172-4",
@@ -1207,6 +1469,11 @@ static const struct of_device_id ad7173_of_match[] = {
 MODULE_DEVICE_TABLE(of, ad7173_of_match);
 
 static const struct spi_device_id ad7173_id_table[] = {
+	{ "ad4111", (kernel_ulong_t)&ad7173_device_info[ID_AD4111]},
+	{ "ad4112", (kernel_ulong_t)&ad7173_device_info[ID_AD4112]},
+	{ "ad4114", (kernel_ulong_t)&ad7173_device_info[ID_AD4114]},
+	{ "ad4115", (kernel_ulong_t)&ad7173_device_info[ID_AD4115]},
+	{ "ad4116", (kernel_ulong_t)&ad7173_device_info[ID_AD4116]},
 	{ "ad7172-2", (kernel_ulong_t)&ad7173_device_info[ID_AD7172_2]},
 	{ "ad7172-4", (kernel_ulong_t)&ad7173_device_info[ID_AD7172_4]},
 	{ "ad7173-8", (kernel_ulong_t)&ad7173_device_info[ID_AD7173_8]},
@@ -1231,5 +1498,5 @@ 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_DESCRIPTION("Analog Devices AD7173 and similar ADC driver");
 MODULE_LICENSE("GPL");

-- 
2.43.0

On Mon, 2024-05-27 at 20:02 +0300, Dumitru Ceclan via B4 Relay wrote:
> From: Dumitru Ceclan <dumitru.ceclan@analog.com>
> 
> Add support for AD4111/AD4112/AD4114/AD4115/AD4116.
> 
> The AD411X family encompasses a series of low power, low noise, 24-bit,
> sigma-delta analog-to-digital converters that offer a versatile range of
> specifications.
> 
> This family of ADCs integrates an analog front end suitable for processing
> both fully differential and single-ended, bipolar voltage inputs
> addressing a wide array of industrial and instrumentation requirements.
> 
> - All ADCs have inputs with a precision voltage divider with a division
>   ratio of 10.
> - AD4116 has 5 low level inputs without a voltage divider.
> - AD4111 and AD4112 support current inputs (0 mA to 20 mA) using a 50ohm
>   shunt resistor.
> 
> Signed-off-by: Dumitru Ceclan <dumitru.ceclan@analog.com>
> ---
>  drivers/iio/adc/ad7173.c | 327 ++++++++++++++++++++++++++++++++++++++++++-----
>  1 file changed, 297 insertions(+), 30 deletions(-)
> 
> diff --git a/drivers/iio/adc/ad7173.c b/drivers/iio/adc/ad7173.c
> index 106a50dbabd4..328685ce25e0 100644
> --- a/drivers/iio/adc/ad7173.c
> +++ b/drivers/iio/adc/ad7173.c
> @@ -1,8 +1,9 @@
>  // SPDX-License-Identifier: GPL-2.0+
>  /*
> - * AD717x family SPI ADC driver
> + * AD717x and AD411x family SPI ADC driver
>   *
>   * Supported devices:
> + *  AD4111/AD4112/AD4114/AD4115/AD4116
>   *  AD7172-2/AD7172-4/AD7173-8/AD7175-2
>   *  AD7175-8/AD7176-2/AD7177-2
>   *
> @@ -75,7 +76,9 @@
>  #define AD7176_ID			0x0c90
>  #define AD7175_2_ID			0x0cd0
>  #define AD7172_4_ID			0x2050
> -#define AD7173_ID			0x30d0
> +#define AD7173_AD4111_AD4112_AD4114_ID	0x30d0

I would definitely rename this :). Would even prefer to have separate defines all
defined by AD7173_ID.

> +#define AD4116_ID			0x34d0
> +#define AD4115_ID			0x38d0
>  #define AD7175_8_ID			0x3cd0
>  #define AD7177_ID			0x4fd0
>  #define AD7173_ID_MASK			GENMASK(15, 4)
> @@ -106,6 +109,7 @@
>  
>  #define AD7173_GPO12_DATA(x)	BIT((x) + 0)
>  #define AD7173_GPO23_DATA(x)	BIT((x) + 4)
> +#define AD4111_GPO01_DATA(x)	BIT((x) + 6)
>  #define AD7173_GPO_DATA(x)	((x) < 2 ? AD7173_GPO12_DATA(x) :
> AD7173_GPO23_DATA(x))
>  
>  #define AD7173_INTERFACE_DATA_STAT	BIT(6)
> @@ -124,11 +128,20 @@
>  #define AD7173_VOLTAGE_INT_REF_uV	2500000
>  #define AD7173_TEMP_SENSIIVITY_uV_per_C	477
>  #define AD7177_ODR_START_VALUE		0x07
> +#define AD4111_SHUNT_RESISTOR_OHM	50
> +#define AD4111_DIVIDER_RATIO		10
> +#define AD411X_VCOM_INPUT		0X10
> +#define AD4111_CURRENT_CHAN_CUTOFF	16
>  
>  #define AD7173_FILTER_ODR0_MASK		GENMASK(5, 0)
>  #define AD7173_MAX_CONFIGS		8
>  
>  enum ad7173_ids {
> +	ID_AD4111,
> +	ID_AD4112,
> +	ID_AD4114,
> +	ID_AD4115,
> +	ID_AD4116,
>  	ID_AD7172_2,
>  	ID_AD7172_4,
>  	ID_AD7173_8,
> @@ -138,22 +151,43 @@ enum ad7173_ids {
>  	ID_AD7177_2,
>  };
>  
> +enum ad4111_current_channels {
> +	AD4111_CURRENT_IN0P_IN0N,
> +	AD4111_CURRENT_IN1P_IN1N,
> +	AD4111_CURRENT_IN2P_IN2N,
> +	AD4111_CURRENT_IN3P_IN3N,
> +};
> +
> +enum ad7173_channel_types {
> +	AD7173_CHAN_SINGLE_ENDED,
> +	AD7173_CHAN_DIFFERENTIAL,
> +};
> +
>  struct ad7173_device_info {
>  	const unsigned int *sinc5_data_rates;
>  	unsigned int num_sinc5_data_rates;
>  	unsigned int odr_start_value;
> +	/*
> +	 * AD4116 has both inputs with a volage divider and without.

s/volage/voltage

> +	 * These inputs cannot be mixed in the channel configuration.
> +	 * Does not include the VCOM input.
> +	 */
> +	unsigned int num_voltage_inputs_with_divider;

nit: maybe num_voltage_in_div?

>  	unsigned int num_channels;
>  	unsigned int num_configs;
> -	unsigned int num_inputs;
> +	unsigned int num_voltage_inputs;

nit: maybe num_voltage_in?

>  	unsigned int clock;
>  	unsigned int id;
>  	char *name;
> +	bool has_current_inputs;
> +	bool has_vcom_input;
>  	bool has_temp;
>  	/* ((AVDD1 − AVSS)/5) */
>  	bool has_common_input;
>  	bool has_input_buf;
>  	bool has_int_ref;
>  	bool has_ref2;
> +	bool higher_gpio_bits;
>  	u8 num_gpios;
>  };
>  
> @@ -195,6 +229,24 @@ struct ad7173_state {
>  #endif
>  };
>  
> +static unsigned int ad4115_sinc5_data_rates[] = {
> +	24845000, 24845000, 20725000, 20725000,	/*  0-3  */
> +	15564000, 13841000, 10390000, 10390000,	/*  4-7  */
> +	4994000,  2499000,  1000000,  500000,	/*  8-11 */
> +	395500,   200000,   100000,   59890,	/* 12-15 */
> +	49920,    20000,    16660,    10000,	/* 16-19 */
> +	5000,	  2500,     2500,		/* 20-22 */
> +};
> +
> +static unsigned int ad4116_sinc5_data_rates[] = {
> +	12422360, 12422360, 12422360, 12422360,	/*  0-3  */
> +	10362690, 10362690, 7782100,  6290530,	/*  4-7  */
> +	5194800,  2496900,  1007600,  499900,	/*  8-11 */
> +	390600,	  200300,   100000,   59750,	/* 12-15 */
> +	49840,	  20000,    16650,    10000,	/* 16-19 */
> +	5000,	  2500,	    1250,		/* 20-22 */
> +};
> +
>  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 */
> @@ -210,14 +262,109 @@ static const unsigned int ad7175_sinc5_data_rates[] = {
>  	5000,					/* 20    */
>  };
>  
> +static unsigned int ad4111_current_channel_config[] = {
> +	[AD4111_CURRENT_IN0P_IN0N] = 0x1E8,
> +	[AD4111_CURRENT_IN1P_IN1N] = 0x1C9,
> +	[AD4111_CURRENT_IN2P_IN2N] = 0x1AA,
> +	[AD4111_CURRENT_IN3P_IN3N] = 0x18B,
> +};
> +
>  static const struct ad7173_device_info ad7173_device_info[] = {
> +	[ID_AD4111] = {
> +		.name = "ad4111",
> +		.id = AD7173_AD4111_AD4112_AD4114_ID,
> +		.num_voltage_inputs_with_divider = 8,
> +		.num_channels = 16,
> +		.num_configs = 8,
> +		.num_voltage_inputs = 8,
> +		.num_gpios = 2,
> +		.higher_gpio_bits = true,
> +		.has_temp = true,
> +		.has_vcom_input = true,
> +		.has_input_buf = true,
> +		.has_current_inputs = true,
> +		.has_int_ref = true,
> +		.clock = 2 * HZ_PER_MHZ,
> +		.sinc5_data_rates = ad7173_sinc5_data_rates,
> +		.num_sinc5_data_rates = ARRAY_SIZE(ad7173_sinc5_data_rates),
> +	},

At some point it would be nice to drop the ad7173_device_info array...

...

> 
> @@ -688,18 +858,33 @@ static int ad7173_read_raw(struct iio_dev *indio_dev,
>  
>  		return IIO_VAL_INT;
>  	case IIO_CHAN_INFO_SCALE:
> -		if (chan->type == IIO_TEMP) {
> +
> +		switch (chan->type) {
> +		case IIO_TEMP:
>  			temp = AD7173_VOLTAGE_INT_REF_uV * MILLI;
>  			temp /= AD7173_TEMP_SENSIIVITY_uV_per_C;
>  			*val = temp;
>  			*val2 = chan->scan_type.realbits;
> -		} else {
> +			return IIO_VAL_FRACTIONAL_LOG2;
> +		case IIO_VOLTAGE:
>  			*val = ad7173_get_ref_voltage_milli(st, ch->cfg.ref_sel);
>  			*val2 = chan->scan_type.realbits - !!(ch->cfg.bipolar);
> +
> +			if (chan->channel < st->info-
> >num_voltage_inputs_with_divider)
> +				*val *= AD4111_DIVIDER_RATIO;
> +			return IIO_VAL_FRACTIONAL_LOG2;
> +		case IIO_CURRENT:
> +			*val = ad7173_get_ref_voltage_milli(st, ch->cfg.ref_sel);
> +			*val /= AD4111_SHUNT_RESISTOR_OHM;
> +			*val2 = chan->scan_type.realbits - (ch->cfg.bipolar ? 1 :
> 0);

Can bipolar have any other value than 0 or 1? Just subtract it directly...

> +			return IIO_VAL_FRACTIONAL_LOG2;
> +		default:
> +			return -EINVAL;
>  		}
> -		return IIO_VAL_FRACTIONAL_LOG2;
>  	case IIO_CHAN_INFO_OFFSET:
> -		if (chan->type == IIO_TEMP) {
> +
> +		switch (chan->type) {
> +		case IIO_TEMP:
>  			/* 0 Kelvin -> raw sample */
>  			temp   = -ABSOLUTE_ZERO_MILLICELSIUS;
>  			temp  *= AD7173_TEMP_SENSIIVITY_uV_per_C;
> @@ -708,10 +893,14 @@ static int ad7173_read_raw(struct iio_dev *indio_dev,
>  						       AD7173_VOLTAGE_INT_REF_uV *
>  						       MILLI);
>  			*val   = -temp;
> -		} else {
> +			return IIO_VAL_INT;
> +		case IIO_VOLTAGE:
> +		case IIO_CURRENT:
>  			*val = -BIT(chan->scan_type.realbits - 1);
> +			return IIO_VAL_INT;
> +		default:
> +			return -EINVAL;
>  		}
> -		return IIO_VAL_INT;
>  	case IIO_CHAN_INFO_SAMP_FREQ:
>  		reg = st->channels[chan->address].cfg.odr;
>  
> @@ -919,13 +1108,34 @@ static int ad7173_register_clk_provider(struct iio_dev
> *indio_dev)
>  					   &st->int_clk_hw);
>  }
>  
> +static int ad4111_validate_current_ain(struct ad7173_state *st,
> +				       unsigned int ain[2])

Hmm, pass by reference... Should also be const AFAICT.

...

>  
> @@ -1022,12 +1248,23 @@ static int ad7173_fw_parse_channel_config(struct iio_dev
> *indio_dev)
>  		chan_st_priv = &chans_st_arr[chan_index];
>  		ret = fwnode_property_read_u32_array(child, "diff-channels",
>  						     ain, ARRAY_SIZE(ain));
> -		if (ret)
> -			return ret;
> +		if (ret) {
> +			ret = fwnode_property_read_u32_array(child, "single-
> channel",
> +							     ain, 1);
> +			if (ret)
> +				return ret;
>  
> -		ret = ad7173_validate_voltage_ain_inputs(st, ain);
> -		if (ret)
> -			return ret;
> +			ret = ad4111_validate_current_ain(st, ain);
> +			if (ret)
> +				return ret;
> +			is_current_chan = true;
> +			ain[1] = 0;
> +		} else {
> +			ret = ad7173_validate_voltage_ain_inputs(st, ain);
> +			if (ret)
> +				return ret;
> +			is_current_chan = false;
> +		}
>  
>  		ret = fwnode_property_match_property_string(child,
>  							    "adi,reference-
> select",
> @@ -1051,17 +1288,34 @@ static int ad7173_fw_parse_channel_config(struct iio_dev
> *indio_dev)
>  		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 = st->info->has_input_buf;
>  		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);
>  
> +		ret = fwnode_property_match_property_string(child,
> +							    "adi,channel-type",
> +							    ad7173_channel_types,
> +							   
> ARRAY_SIZE(ad7173_channel_types));
> +		chan->differential = (ret < 0 || ret == AD7173_CHAN_DIFFERENTIAL)
> +					? 1 : 0;

I don't think we should treat 'ret < 0' has a differential channel. Any reason for
it? For me, it's just an invalid property value given by the user...

- Nuno Sá

On 29/05/2024 15:46, Nuno Sá wrote:
> On Mon, 2024-05-27 at 20:02 +0300, Dumitru Ceclan via B4 Relay wrote:
>> From: Dumitru Ceclan <dumitru.ceclan@analog.com>

...

>>  static const struct ad7173_device_info ad7173_device_info[] = {
>> +	[ID_AD4111] = {
>> +		.name = "ad4111",
>> +		.id = AD7173_AD4111_AD4112_AD4114_ID,
>> +		.num_voltage_inputs_with_divider = 8,
>> +		.num_channels = 16,
>> +		.num_configs = 8,
>> +		.num_voltage_inputs = 8,
>> +		.num_gpios = 2,
>> +		.higher_gpio_bits = true,
>> +		.has_temp = true,
>> +		.has_vcom_input = true,
>> +		.has_input_buf = true,
>> +		.has_current_inputs = true,
>> +		.has_int_ref = true,
>> +		.clock = 2 * HZ_PER_MHZ,
>> +		.sinc5_data_rates = ad7173_sinc5_data_rates,
>> +		.num_sinc5_data_rates = ARRAY_SIZE(ad7173_sinc5_data_rates),
>> +	},
> 
> At some point it would be nice to drop the ad7173_device_info array...
> 
What are good alternatives to this?
...

>> +		ret = fwnode_property_match_property_string(child,
>> +							    "adi,channel-type",
>> +							    ad7173_channel_types,
>> +							   
>> ARRAY_SIZE(ad7173_channel_types));
>> +		chan->differential = (ret < 0 || ret == AD7173_CHAN_DIFFERENTIAL)
>> +					? 1 : 0;
> 
> I don't think we should treat 'ret < 0' has a differential channel. Any reason for
> it? For me, it's just an invalid property value given by the user...
> 
Yes, as that would be the default value if it's missing or invalid

> - Nuno Sá
> 

On 5/29/24 9:03 AM, Ceclan, Dumitru wrote:
> On 29/05/2024 15:46, Nuno Sá wrote:
>> On Mon, 2024-05-27 at 20:02 +0300, Dumitru Ceclan via B4 Relay wrote:
>>> From: Dumitru Ceclan <dumitru.ceclan@analog.com>
> 
> ...
> 
>>>  static const struct ad7173_device_info ad7173_device_info[] = {
>>> +	[ID_AD4111] = {
>>> +		.name = "ad4111",
>>> +		.id = AD7173_AD4111_AD4112_AD4114_ID,
>>> +		.num_voltage_inputs_with_divider = 8,
>>> +		.num_channels = 16,
>>> +		.num_configs = 8,
>>> +		.num_voltage_inputs = 8,
>>> +		.num_gpios = 2,
>>> +		.higher_gpio_bits = true,
>>> +		.has_temp = true,
>>> +		.has_vcom_input = true,
>>> +		.has_input_buf = true,
>>> +		.has_current_inputs = true,
>>> +		.has_int_ref = true,
>>> +		.clock = 2 * HZ_PER_MHZ,
>>> +		.sinc5_data_rates = ad7173_sinc5_data_rates,
>>> +		.num_sinc5_data_rates = ARRAY_SIZE(ad7173_sinc5_data_rates),
>>> +	},
>>
>> At some point it would be nice to drop the ad7173_device_info array...
>>
> What are good alternatives to this?

Drivers like ad7091r8 have individual static struct ad7091r_init_info
instead of putting them all in an array. I like doing it that
way because it makes less code to read compared to having the
array.

It would let us get rid of enum ad7173_ids, have one level less
indent on each static const struct ad7173_device_info and 

{ .compatible = "adi,ad7172-2", .data = &ad7173_device_info },

would now fit on one line since we no longer need the array
index.

On Wed, 2024-05-29 at 15:59 -0500, David Lechner wrote:
> On 5/29/24 9:03 AM, Ceclan, Dumitru wrote:
> > On 29/05/2024 15:46, Nuno Sá wrote:
> > > On Mon, 2024-05-27 at 20:02 +0300, Dumitru Ceclan via B4 Relay wrote:
> > > > From: Dumitru Ceclan <dumitru.ceclan@analog.com>
> > 
> > ...
> > 
> > > >  static const struct ad7173_device_info ad7173_device_info[] = {
> > > > +	[ID_AD4111] = {
> > > > +		.name = "ad4111",
> > > > +		.id = AD7173_AD4111_AD4112_AD4114_ID,
> > > > +		.num_voltage_inputs_with_divider = 8,
> > > > +		.num_channels = 16,
> > > > +		.num_configs = 8,
> > > > +		.num_voltage_inputs = 8,
> > > > +		.num_gpios = 2,
> > > > +		.higher_gpio_bits = true,
> > > > +		.has_temp = true,
> > > > +		.has_vcom_input = true,
> > > > +		.has_input_buf = true,
> > > > +		.has_current_inputs = true,
> > > > +		.has_int_ref = true,
> > > > +		.clock = 2 * HZ_PER_MHZ,
> > > > +		.sinc5_data_rates = ad7173_sinc5_data_rates,
> > > > +		.num_sinc5_data_rates = ARRAY_SIZE(ad7173_sinc5_data_rates),
> > > > +	},
> > > 
> > > At some point it would be nice to drop the ad7173_device_info array...
> > > 
> > What are good alternatives to this?
> 
> Drivers like ad7091r8 have individual static struct ad7091r_init_info
> instead of putting them all in an array. I like doing it that
> way because it makes less code to read compared to having the
> array.
> 
> It would let us get rid of enum ad7173_ids, have one level less
> indent on each static const struct ad7173_device_info and 
> 
> { .compatible = "adi,ad7172-2", .data = &ad7173_device_info },
> 
> would now fit on one line since we no longer need the array
> index.
> 

Exactly... But up to you to do it now or defer it to a later patch.

- Nuno Sá

On Thu, 30 May 2024 08:19:57 +0200
Nuno Sá <noname.nuno@gmail.com> wrote:

> On Wed, 2024-05-29 at 15:59 -0500, David Lechner wrote:
> > On 5/29/24 9:03 AM, Ceclan, Dumitru wrote:  
> > > On 29/05/2024 15:46, Nuno Sá wrote:  
> > > > On Mon, 2024-05-27 at 20:02 +0300, Dumitru Ceclan via B4 Relay wrote:  
> > > > > From: Dumitru Ceclan <dumitru.ceclan@analog.com>  
> > > 
> > > ...
> > >   
> > > > >  static const struct ad7173_device_info ad7173_device_info[] = {
> > > > > +	[ID_AD4111] = {
> > > > > +		.name = "ad4111",
> > > > > +		.id = AD7173_AD4111_AD4112_AD4114_ID,
> > > > > +		.num_voltage_inputs_with_divider = 8,
> > > > > +		.num_channels = 16,
> > > > > +		.num_configs = 8,
> > > > > +		.num_voltage_inputs = 8,
> > > > > +		.num_gpios = 2,
> > > > > +		.higher_gpio_bits = true,
> > > > > +		.has_temp = true,
> > > > > +		.has_vcom_input = true,
> > > > > +		.has_input_buf = true,
> > > > > +		.has_current_inputs = true,
> > > > > +		.has_int_ref = true,
> > > > > +		.clock = 2 * HZ_PER_MHZ,
> > > > > +		.sinc5_data_rates = ad7173_sinc5_data_rates,
> > > > > +		.num_sinc5_data_rates = ARRAY_SIZE(ad7173_sinc5_data_rates),
> > > > > +	},  
> > > > 
> > > > At some point it would be nice to drop the ad7173_device_info array...
> > > >   
> > > What are good alternatives to this?  
> > 
> > Drivers like ad7091r8 have individual static struct ad7091r_init_info
> > instead of putting them all in an array. I like doing it that
> > way because it makes less code to read compared to having the
> > array.
> > 
> > It would let us get rid of enum ad7173_ids, have one level less
> > indent on each static const struct ad7173_device_info and 
> > 
> > { .compatible = "adi,ad7172-2", .data = &ad7173_device_info },
> > 
> > would now fit on one line since we no longer need the array
> > index.
> >   
> 
> Exactly... But up to you to do it now or defer it to a later patch.
> 
Agreed - the array pattern for this is not a good idea as it
also encourages people to assign meaning to the enum values leaving
stuff expressed as code that should be a flag or value inside these
device_info structures.

Some of those where mistakes of a younger me ;(

Jonathan

> - Nuno Sá