Message-ID: <20250829030512.1179998-5-chris.packham@alliedtelesis.co.nz>
Date: Fri, 29 Aug 2025 15:05:12 +1200
From: Chris Packham <chris.packham@...iedtelesis.co.nz>
To: jdelvare@...e.com,
	linux@...ck-us.net,
	robh@...nel.org,
	krzk+dt@...nel.org,
	conor+dt@...nel.org,
	corbet@....net,
	wenliang202407@....com,
	jre@...gutronix.de
Cc: linux-hwmon@...r.kernel.org,
	devicetree@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	linux-doc@...r.kernel.org,
	Chris Packham <chris.packham@...iedtelesis.co.nz>
Subject: [PATCH v3 4/4] hwmon: (ina238) Add support for INA780

Add support for the TI INA780 Digital Power Monitor. The INA780 uses
EZShunt(tm) technology, which means there are fixed LSB conversions for
a number of fields rather than needing to be calibrated.

Signed-off-by: Chris Packham <chris.packham@...iedtelesis.co.nz>
---

Notes:
    Changes in v3:
    - Rebase on top of master and resolve conflicts with commit fd470f4ed80c
      ("hwmon: (ina238) Add support for INA228")
    - Use INA238_SHUNT_OVER/UNDER_VOLTAGE register definitions with comment
      about COL/CUL.
    - Move some code to prepartory patches

 Documentation/hwmon/ina238.rst |  20 +++
 drivers/hwmon/ina238.c         | 251 +++++++++++++++++++++++++--------
 2 files changed, 216 insertions(+), 55 deletions(-)

diff --git a/Documentation/hwmon/ina238.rst b/Documentation/hwmon/ina238.rst
index 9a24da4786a4..220d36d5c947 100644
--- a/Documentation/hwmon/ina238.rst
+++ b/Documentation/hwmon/ina238.rst
@@ -14,6 +14,11 @@ Supported chips:
     Datasheet:
 	https://www.ti.com/lit/gpn/ina238
 
+  * Texas Instruments INA780
+
+    Datasheet:
+	https://www.ti.com/product/ina780a
+
   * Silergy SQ52206
 
     Prefix: 'SQ52206'
@@ -69,3 +74,18 @@ energy1_input		Energy measurement (uJ)
 
 power1_input_highest	Peak Power (uW)
 ======================= =======================================================
+
+Sysfs differences for ina780
+----------------------------
+
+======================= =======================================================
+in0_input		Bus voltage (mV)
+in0_min			Minimum bus voltage threshold (mV)
+in0_min_alarm		Minimum shunt voltage alarm
+in0_max			Maximum bus voltage threshold (mV)
+in0_max_alarm		Maximum shunt voltage alarm
+curr1_max		Maximum current threshold
+curr1_max_alarm		Maximum current alarm
+curr1_min		Minimum current threshold
+curr1_min_alarm		Minimum current alarm
+======================= =======================================================
diff --git a/drivers/hwmon/ina238.c b/drivers/hwmon/ina238.c
index 930e12e64079..ad1b36762ca3 100644
--- a/drivers/hwmon/ina238.c
+++ b/drivers/hwmon/ina238.c
@@ -2,6 +2,7 @@
 /*
  * Driver for Texas Instruments INA238 power monitor chip
  * Datasheet: https://www.ti.com/product/ina238
+ *            https://www.ti.com/product/ina780a
  *
  * Copyright (C) 2021 Nathan Rossi <nathan.rossi@...i.com>
  */
@@ -31,8 +32,8 @@
 #define SQ52206_ENERGY			0x9
 #define SQ52206_CHARGE			0xa
 #define INA238_DIAG_ALERT		0xb
-#define INA238_SHUNT_OVER_VOLTAGE	0xc
-#define INA238_SHUNT_UNDER_VOLTAGE	0xd
+#define INA238_SHUNT_OVER_VOLTAGE	0xc /* COL on INA780 */
+#define INA238_SHUNT_UNDER_VOLTAGE	0xd /* CUL on INA780 */
 #define INA238_BUS_OVER_VOLTAGE		0xe
 #define INA238_BUS_UNDER_VOLTAGE	0xf
 #define INA238_TEMP_LIMIT		0x10
@@ -45,8 +46,8 @@
 #define SQ52206_CONFIG_ADCRANGE_LOW	BIT(3)
 
 #define INA238_DIAG_ALERT_TMPOL		BIT(7)
-#define INA238_DIAG_ALERT_SHNTOL	BIT(6)
-#define INA238_DIAG_ALERT_SHNTUL	BIT(5)
+#define INA238_DIAG_ALERT_SHNTOL	BIT(6) /* CURRENTOL on INA780 */
+#define INA238_DIAG_ALERT_SHNTUL	BIT(5) /* CURRENTUL on INA780 */
 #define INA238_DIAG_ALERT_BUSOL		BIT(4)
 #define INA238_DIAG_ALERT_BUSUL		BIT(3)
 #define INA238_DIAG_ALERT_POL		BIT(2)
@@ -110,13 +111,16 @@
 #define SQ52206_DIE_TEMP_LSB		78125 /* 7.8125 mC/lsb */
 #define INA228_DIE_TEMP_LSB		78125 /* 7.8125 mC/lsb */
 
+#define INA780_CURRENT_LSB		2400	/* 2.4 mA/lsb  */
+#define INA780_ENERGY_LSB		7680	/* 7.68 mJ/lsb */
+
 static const struct regmap_config ina238_regmap_config = {
 	.max_register = INA238_REGISTERS,
 	.reg_bits = 8,
 	.val_bits = 16,
 };
 
-enum ina238_ids { ina238, ina237, sq52206, ina228 };
+enum ina238_ids { ina238, ina237, sq52206, ina228, ina780 };
 
 struct ina238_config {
 	bool has_20bit_voltage_current; /* vshunt, vbus and current are 20-bit fields */
@@ -199,6 +203,19 @@ static const struct ina238_config ina238_config[] = {
 		.temp_max = 125000,
 		.fixed_power_lsb = 0,
 	},
+	[ina780] = {
+		.has_20bit_voltage_current = false,
+		.has_shunt = false,
+		.has_energy = true,
+		.has_power_highest = false,
+		.temp_shift = 4,
+		.config_default = INA238_CONFIG_DEFAULT,
+		.bus_voltage_lsb = INA238_BUS_VOLTAGE_LSB,
+		.temp_lsb = INA238_DIE_TEMP_LSB,
+		.temp_max = 150000,
+		.fixed_power_lsb = 480,
+		.has_curr_min_max = true,
+	}
 };
 
 static int ina238_read_reg24(const struct i2c_client *client, u8 reg, u32 *val)
@@ -298,12 +315,12 @@ static int ina238_read_in(struct device *dev, u32 attr, int channel,
 			  long *val)
 {
 	struct ina238_data *data = dev_get_drvdata(dev);
+	bool has_shunt = data->config->has_shunt;
 	int reg, mask;
 	int regval;
 	int err;
 
-	switch (channel) {
-	case 0:
+	if (has_shunt && channel == 0) {
 		switch (attr) {
 		case hwmon_in_input:
 			if (data->config->has_20bit_voltage_current)
@@ -327,8 +344,7 @@ static int ina238_read_in(struct device *dev, u32 attr, int channel,
 		default:
 			return -EOPNOTSUPP;
 		}
-		break;
-	case 1:
+	} else {
 		switch (attr) {
 		case hwmon_in_input:
 			if (data->config->has_20bit_voltage_current)
@@ -352,9 +368,6 @@ static int ina238_read_in(struct device *dev, u32 attr, int channel,
 		default:
 			return -EOPNOTSUPP;
 		}
-		break;
-	default:
-		return -EOPNOTSUPP;
 	}
 
 	err = regmap_read(data->regmap, reg, &regval);
@@ -367,7 +380,7 @@ static int ina238_read_in(struct device *dev, u32 attr, int channel,
 	case hwmon_in_min:
 		/* signed register, value in mV */
 		regval = (s16)regval;
-		if (channel == 0)
+		if (has_shunt && channel == 0)
 			/* gain of 1 -> LSB / 4 */
 			*val = (regval * INA238_SHUNT_VOLTAGE_LSB) *
 				data->gain / (1000 * 4);
@@ -387,14 +400,14 @@ static int ina238_write_in(struct device *dev, u32 attr, int channel,
 			   long val)
 {
 	struct ina238_data *data = dev_get_drvdata(dev);
+	bool has_shunt = data->config->has_shunt;
 	int regval;
 
 	if (attr != hwmon_in_max && attr != hwmon_in_min)
 		return -EOPNOTSUPP;
 
 	/* convert decimal to register value */
-	switch (channel) {
-	case 0:
+	if (has_shunt && channel == 0) {
 		/* signed value, clamp to max range +/-163 mV */
 		regval = clamp_val(val, -163, 163);
 		regval = (regval * 1000 * 4) /
@@ -411,7 +424,7 @@ static int ina238_write_in(struct device *dev, u32 attr, int channel,
 		default:
 			return -EOPNOTSUPP;
 		}
-	case 1:
+	} else {
 		/* signed value, positive values only. Clamp to max 102.396 V */
 		regval = clamp_val(val, 0, 102396);
 		regval = (regval * 1000) / data->config->bus_voltage_lsb;
@@ -427,8 +440,6 @@ static int ina238_write_in(struct device *dev, u32 attr, int channel,
 		default:
 			return -EOPNOTSUPP;
 		}
-	default:
-		return -EOPNOTSUPP;
 	}
 }
 
@@ -467,9 +478,86 @@ static int ina238_read_current(struct device *dev, u32 attr, long *val)
 	return 0;
 }
 
+static int ina780_read_current(struct device *dev, u32 attr, long *val)
+{
+	struct ina238_data *data = dev_get_drvdata(dev);
+	unsigned int regval;
+	int reg, mask;
+	int err;
+
+	switch (attr) {
+	case hwmon_curr_input:
+		reg = INA238_CURRENT;
+		break;
+	case hwmon_curr_max:
+		reg = INA238_SHUNT_OVER_VOLTAGE;
+		break;
+	case hwmon_curr_min:
+		reg = INA238_SHUNT_UNDER_VOLTAGE;
+		break;
+	case hwmon_curr_max_alarm:
+		reg = INA238_DIAG_ALERT;
+		mask = INA238_DIAG_ALERT_SHNTOL;
+		break;
+	case hwmon_curr_min_alarm:
+		reg = INA238_DIAG_ALERT;
+		mask = INA238_DIAG_ALERT_SHNTUL;
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	switch (attr) {
+	case hwmon_curr_input:
+	case hwmon_curr_max:
+	case hwmon_curr_min:
+		err = regmap_read(data->regmap, reg, &regval);
+		if (err)
+			return err;
+		*val = div_s64((s16)regval * INA780_CURRENT_LSB, 1000);
+		break;
+	case hwmon_curr_max_alarm:
+	case hwmon_curr_min_alarm:
+		err = regmap_read(data->regmap, reg, &regval);
+		if (err)
+			return err;
+		*val = !!(regval & mask);
+		break;
+	}
+
+	return 0;
+}
+
+static int ina780_write_current(struct device *dev, u32 attr, long val)
+{
+	struct ina238_data *data = dev_get_drvdata(dev);
+	bool has_curr_min_max = data->config->has_curr_min_max;
+	unsigned int regval;
+	int reg;
+
+	if (!has_curr_min_max)
+		return -EOPNOTSUPP;
+
+	switch (attr) {
+	case hwmon_curr_max:
+		reg = INA238_SHUNT_OVER_VOLTAGE;
+		break;
+	case hwmon_curr_min:
+		reg = INA238_SHUNT_UNDER_VOLTAGE;
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+	clamp_val(val, -78643, 78640);
+	regval = div_s64(val * 1000ULL, INA780_CURRENT_LSB);
+
+	return regmap_write(data->regmap, reg, regval);
+}
+
 static int ina238_read_power(struct device *dev, u32 attr, long *val)
 {
 	struct ina238_data *data = dev_get_drvdata(dev);
+	long long fixed_power_lsb = data->config->fixed_power_lsb;
 	long long power;
 	int regval;
 	int err;
@@ -480,9 +568,14 @@ static int ina238_read_power(struct device *dev, u32 attr, long *val)
 		if (err)
 			return err;
 
-		/* Fixed 1mA lsb, scaled by 1000000 to have result in uW */
-		power = div_u64(regval * 1000ULL * INA238_FIXED_SHUNT * data->gain *
-				data->config->power_calculate_factor, 4 * 100 * data->rshunt);
+		if (fixed_power_lsb)
+			power = div_u64(regval * fixed_power_lsb, 1000);
+		else
+			/* Fixed 1mA lsb, scaled by 1000000 to have result in uW */
+			power = div_u64(regval * 1000ULL * INA238_FIXED_SHUNT * data->gain *
+					data->config->power_calculate_factor,
+					4 * 100 * data->rshunt);
+
 		/* Clamp value to maximum value of long */
 		*val = clamp_val(power, 0, LONG_MAX);
 		break;
@@ -506,8 +599,12 @@ static int ina238_read_power(struct device *dev, u32 attr, long *val)
 		 * Truncated 24-bit compare register, lower 8-bits are
 		 * truncated. Same conversion to/from uW as POWER register.
 		 */
-		power = div_u64((regval << 8) * 1000ULL * INA238_FIXED_SHUNT * data->gain *
-				data->config->power_calculate_factor, 4 * 100 * data->rshunt);
+		if (fixed_power_lsb)
+			power = div_u64((regval << 8) * fixed_power_lsb * 256, 1000);
+		else
+			power = div_u64((regval << 8) * 1000ULL * INA238_FIXED_SHUNT * data->gain *
+					data->config->power_calculate_factor,
+					4 * 100 * data->rshunt);
 		/* Clamp value to maximum value of long */
 		*val = clamp_val(power, 0, LONG_MAX);
 		break;
@@ -528,6 +625,7 @@ static int ina238_read_power(struct device *dev, u32 attr, long *val)
 static int ina238_write_power(struct device *dev, u32 attr, long val)
 {
 	struct ina238_data *data = dev_get_drvdata(dev);
+	int fixed_power_lsb = data->config->fixed_power_lsb;
 	long regval;
 
 	if (attr != hwmon_power_max)
@@ -539,8 +637,12 @@ static int ina238_write_power(struct device *dev, u32 attr, long val)
 	 * register.
 	 */
 	regval = clamp_val(val, 0, LONG_MAX);
-	regval = div_u64(val * 4 * 100 * data->rshunt, data->config->power_calculate_factor *
-			1000ULL * INA238_FIXED_SHUNT * data->gain);
+	if (fixed_power_lsb)
+		regval = div_u64(val * 1000ULL, fixed_power_lsb);
+	else
+		regval = div_u64(val * 4 * 100 * data->rshunt,
+				 data->config->power_calculate_factor *
+				 1000ULL * INA238_FIXED_SHUNT * data->gain);
 	regval = clamp_val(regval >> 8, 0, U16_MAX);
 
 	return regmap_write(data->regmap, INA238_POWER_LIMIT, regval);
@@ -603,6 +705,7 @@ static ssize_t energy1_input_show(struct device *dev,
 				  struct device_attribute *da, char *buf)
 {
 	struct ina238_data *data = dev_get_drvdata(dev);
+	bool has_shunt = data->config->has_shunt;
 	int ret;
 	u64 regval;
 	u64 energy;
@@ -612,8 +715,11 @@ static ssize_t energy1_input_show(struct device *dev,
 		return ret;
 
 	/* result in uJ */
-	energy = div_u64(regval * INA238_FIXED_SHUNT * data->gain * 16 * 10 *
-			 data->config->power_calculate_factor, 4 * data->rshunt);
+	if (has_shunt)
+		energy = div_u64(regval * INA238_FIXED_SHUNT *	data->gain * 16 * 10 *
+					data->config->power_calculate_factor, 4 * data->rshunt);
+	else
+		energy = div_u64(regval * INA780_ENERGY_LSB, 1000);
 
 	return sysfs_emit(buf, "%llu\n", energy);
 }
@@ -621,11 +727,17 @@ static ssize_t energy1_input_show(struct device *dev,
 static int ina238_read(struct device *dev, enum hwmon_sensor_types type,
 		       u32 attr, int channel, long *val)
 {
+	struct ina238_data *data = dev_get_drvdata(dev);
+	bool has_curr_min_max = data->config->has_curr_min_max;
+
 	switch (type) {
 	case hwmon_in:
 		return ina238_read_in(dev, attr, channel, val);
 	case hwmon_curr:
-		return ina238_read_current(dev, attr, val);
+		if (has_curr_min_max)
+			return ina780_read_current(dev, attr, val);
+		else
+			return ina238_read_current(dev, attr, val);
 	case hwmon_power:
 		return ina238_read_power(dev, attr, val);
 	case hwmon_temp:
@@ -648,6 +760,9 @@ static int ina238_write(struct device *dev, enum hwmon_sensor_types type,
 	case hwmon_in:
 		err = ina238_write_in(dev, attr, channel, val);
 		break;
+	case hwmon_curr:
+		err = ina780_write_current(dev, attr, val);
+		break;
 	case hwmon_power:
 		err = ina238_write_power(dev, attr, val);
 		break;
@@ -669,6 +784,8 @@ static umode_t ina238_is_visible(const void *drvdata,
 {
 	const struct ina238_data *data = drvdata;
 	bool has_power_highest = data->config->has_power_highest;
+	bool has_curr_min_max = data->config->has_curr_min_max;
+	bool has_shunt = data->config->has_shunt;
 
 	switch (type) {
 	case hwmon_in:
@@ -676,10 +793,14 @@ static umode_t ina238_is_visible(const void *drvdata,
 		case hwmon_in_input:
 		case hwmon_in_max_alarm:
 		case hwmon_in_min_alarm:
-			return 0444;
+			if (channel == 0 || has_shunt)
+				return 0444;
+			return 0;
 		case hwmon_in_max:
 		case hwmon_in_min:
-			return 0644;
+			if (channel == 0 || has_shunt)
+				return 0644;
+			return 0;
 		default:
 			return 0;
 		}
@@ -687,6 +808,13 @@ static umode_t ina238_is_visible(const void *drvdata,
 		switch (attr) {
 		case hwmon_curr_input:
 			return 0444;
+		case hwmon_curr_max:
+		case hwmon_curr_min:
+		case hwmon_curr_max_alarm:
+		case hwmon_curr_min_alarm:
+			if (has_curr_min_max)
+				return 0644;
+			return 0;
 		default:
 			return 0;
 		}
@@ -725,13 +853,16 @@ static umode_t ina238_is_visible(const void *drvdata,
 
 static const struct hwmon_channel_info * const ina238_info[] = {
 	HWMON_CHANNEL_INFO(in,
-			   /* 0: shunt voltage */
+			   /* 0: shunt voltage (bus voltage for ina780)*/
 			   INA238_HWMON_IN_CONFIG,
-			   /* 1: bus voltage */
+			   /* 1: bus voltage (not present on ina780) */
 			   INA238_HWMON_IN_CONFIG),
 	HWMON_CHANNEL_INFO(curr,
 			   /* 0: current through shunt */
-			   HWMON_C_INPUT),
+			   HWMON_C_INPUT |
+			   /* current limits avialble on ina780*/
+			   HWMON_C_MAX | HWMON_C_MAX_ALARM |
+			   HWMON_C_MIN | HWMON_C_MIN_ALARM),
 	HWMON_CHANNEL_INFO(power,
 			   /* 0: power */
 			   HWMON_P_INPUT | HWMON_P_MAX |
@@ -790,21 +921,23 @@ static int ina238_probe(struct i2c_client *client)
 		return PTR_ERR(data->regmap);
 	}
 
-	/* load shunt value */
-	data->rshunt = INA238_RSHUNT_DEFAULT;
-	if (device_property_read_u32(dev, "shunt-resistor", &data->rshunt) < 0 && pdata)
-		data->rshunt = pdata->shunt_uohms;
-	if (data->rshunt == 0) {
-		dev_err(dev, "invalid shunt resister value %u\n", data->rshunt);
-		return -EINVAL;
-	}
+	if (data->config->has_shunt) {
+		/* load shunt value */
+		data->rshunt = INA238_RSHUNT_DEFAULT;
+		if (device_property_read_u32(dev, "shunt-resistor", &data->rshunt) < 0 && pdata)
+			data->rshunt = pdata->shunt_uohms;
+		if (data->rshunt == 0) {
+			dev_err(dev, "invalid shunt resister value %u\n", data->rshunt);
+			return -EINVAL;
+		}
 
-	/* load shunt gain value */
-	if (device_property_read_u32(dev, "ti,shunt-gain", &data->gain) < 0)
-		data->gain = 4; /* Default of ADCRANGE = 0 */
-	if (data->gain != 1 && data->gain != 2 && data->gain != 4) {
-		dev_err(dev, "invalid shunt gain value %u\n", data->gain);
-		return -EINVAL;
+		/* load shunt gain value */
+		if (device_property_read_u32(dev, "ti,shunt-gain", &data->gain) < 0)
+			data->gain = 4; /* Default of ADCRANGE = 0 */
+		if (data->gain != 1 && data->gain != 2 && data->gain != 4) {
+			dev_err(dev, "invalid shunt gain value %u\n", data->gain);
+			return -EINVAL;
+		}
 	}
 
 	/* Setup CONFIG register */
@@ -831,12 +964,14 @@ static int ina238_probe(struct i2c_client *client)
 		return -ENODEV;
 	}
 
-	/* Setup SHUNT_CALIBRATION register with fixed value */
-	ret = regmap_write(data->regmap, INA238_SHUNT_CALIBRATION,
-			   INA238_CALIBRATION_VALUE);
-	if (ret < 0) {
-		dev_err(dev, "error configuring the device: %d\n", ret);
-		return -ENODEV;
+	if (data->config->has_shunt) {
+		/* Setup SHUNT_CALIBRATION register with fixed value */
+		ret = regmap_write(data->regmap, INA238_SHUNT_CALIBRATION,
+				   INA238_CALIBRATION_VALUE);
+		if (ret < 0) {
+			dev_err(dev, "error configuring the device: %d\n", ret);
+			return -ENODEV;
+		}
 	}
 
 	/* Setup alert/alarm configuration */
@@ -854,8 +989,9 @@ static int ina238_probe(struct i2c_client *client)
 	if (IS_ERR(hwmon_dev))
 		return PTR_ERR(hwmon_dev);
 
-	dev_info(dev, "power monitor %s (Rshunt = %u uOhm, gain = %u)\n",
-		 client->name, data->rshunt, data->gain);
+	if (data->config->has_shunt)
+		dev_info(dev, "power monitor %s (Rshunt = %u uOhm, gain = %u)\n",
+			 client->name, data->rshunt, data->gain);
 
 	return 0;
 }
@@ -865,6 +1001,7 @@ static const struct i2c_device_id ina238_id[] = {
 	{ "ina237", ina237 },
 	{ "ina238", ina238 },
 	{ "sq52206", sq52206 },
+	{ "ina780", ina780 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, ina238_id);
@@ -886,6 +1023,10 @@ static const struct of_device_id __maybe_unused ina238_of_match[] = {
 		.compatible = "silergy,sq52206",
 		.data = (void *)sq52206
 	},
+	{
+		.compatible = "ti,ina780",
+		.data = (void *)ina780
+	},
 	{ }
 };
 MODULE_DEVICE_TABLE(of, ina238_of_match);
-- 
2.51.0

Powered by blists - more mailing lists