kernel: add upstream patches for tps23861 PoE controller

These patches support the tps23861 PoE controller found on a number of
managed switches. The TPS23861 is an I2C-based quad IEEE 802.3at (PoE+)
Power-over-Ethernet PSE controller. It's also found on some Realtek
based switches, where we expect the bulk of the users to reside.

Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
[Disable driver in generic/config-5.10]
Signed-off-by: Sander Vanheule <sander@svanheule.net>

6 files changed, 898 insertions, 0 deletions

diff --git a/target/linux/generic/backport-5.10/871-v5.12-hwmon-add-Texas-Instruments-TPS23861-driver.patch b/target/linux/generic/backport-5.10/871-v5.12-hwmon-add-Texas-Instruments-TPS23861-driver.patch
new file mode 100644
index 0000000000..3c3430a2f7
--- /dev/null
+++ b/target/linux/generic/backport-5.10/871-v5.12-hwmon-add-Texas-Instruments-TPS23861-driver.patch
@@ -0,0 +1,711 @@
+From 97c95dbbba64dbd6e98e033e396695f328033966 Mon Sep 17 00:00:00 2001
+From: Robert Marko <robert.marko@sartura.hr>
+Date: Thu, 21 Jan 2021 14:44:33 +0100
+Subject: [PATCH 1/4] hwmon: add Texas Instruments TPS23861 driver
+
+Add basic monitoring support as well as port on/off control for Texas
+Instruments TPS23861 PoE PSE IC.
+
+Signed-off-by: Robert Marko <robert.marko@sartura.hr>
+Cc: Luka Perkov <luka.perkov@sartura.hr>
+Reviewed-by: Guenter Roeck <linux@roeck-us.net>
+Link: https://lore.kernel.org/r/20210121134434.2782405-2-robert.marko@sartura.hr
+Signed-off-by: Guenter Roeck <linux@roeck-us.net>
+---
+ Documentation/hwmon/index.rst    |   1 +
+ Documentation/hwmon/tps23861.rst |  41 +++
+ drivers/hwmon/Kconfig            |  11 +
+ drivers/hwmon/Makefile           |   1 +
+ drivers/hwmon/tps23861.c         | 601 +++++++++++++++++++++++++++++++
+ 5 files changed, 655 insertions(+)
+ create mode 100644 Documentation/hwmon/tps23861.rst
+ create mode 100644 drivers/hwmon/tps23861.c
+
+--- a/Documentation/hwmon/index.rst
++++ b/Documentation/hwmon/index.rst
+@@ -172,6 +172,7 @@ Hardware Monitoring Kernel Drivers
+    tmp401
+    tmp421
+    tmp513
++   tps23861
+    tps40422
+    tps53679
+    twl4030-madc-hwmon
+--- /dev/null
++++ b/Documentation/hwmon/tps23861.rst
+@@ -0,0 +1,41 @@
++.. SPDX-License-Identifier: GPL-2.0-only
++
++Kernel driver tps23861
++======================
++
++Supported chips:
++  * Texas Instruments TPS23861
++
++    Prefix: 'tps23861'
++
++    Datasheet: https://www.ti.com/lit/gpn/tps23861
++
++Author: Robert Marko <robert.marko@sartura.hr>
++
++Description
++-----------
++
++This driver supports hardware monitoring for Texas Instruments TPS23861 PoE PSE.
++
++TPS23861 is a quad port IEEE802.3at PSE controller with optional I2C control
++and monitoring capabilities.
++
++TPS23861 offers three modes of operation: Auto, Semi-Auto and Manual.
++
++This driver only supports the Auto mode of operation providing monitoring
++as well as enabling/disabling the four ports.
++
++Sysfs entries
++-------------
++
++======================= =====================================================================
++in[0-3]_input		Voltage on ports [1-4]
++in[0-3]_label		"Port[1-4]"
++in4_input		IC input voltage
++in4_label		"Input"
++temp1_input		IC die temperature
++temp1_label		"Die"
++curr[1-4]_input		Current on ports [1-4]
++in[1-4]_label		"Port[1-4]"
++in[0-3]_enable		Enable/disable ports [1-4]
++======================= =====================================================================
+--- a/drivers/hwmon/Kconfig
++++ b/drivers/hwmon/Kconfig
+@@ -1102,6 +1102,17 @@ config SENSORS_TC654
+ 	  This driver can also be built as a module. If so, the module
+ 	  will be called tc654.
+ 
++config SENSORS_TPS23861
++	tristate "Texas Instruments TPS23861 PoE PSE"
++	depends on I2C
++	select REGMAP_I2C
++	help
++	  If you say yes here you get support for Texas Instruments
++	  TPS23861 802.3at PoE PSE chips.
++
++	  This driver can also be built as a module. If so, the module
++	  will be called tps23861.
++
+ config SENSORS_MENF21BMC_HWMON
+ 	tristate "MEN 14F021P00 BMC Hardware Monitoring"
+ 	depends on MFD_MENF21BMC
+--- a/drivers/hwmon/Makefile
++++ b/drivers/hwmon/Makefile
+@@ -141,6 +141,7 @@ obj-$(CONFIG_SENSORS_MAX31790)	+= max317
+ obj-$(CONFIG_SENSORS_MC13783_ADC)+= mc13783-adc.o
+ obj-$(CONFIG_SENSORS_MCP3021)	+= mcp3021.o
+ obj-$(CONFIG_SENSORS_TC654)	+= tc654.o
++obj-$(CONFIG_SENSORS_TPS23861)	+= tps23861.o
+ obj-$(CONFIG_SENSORS_MLXREG_FAN) += mlxreg-fan.o
+ obj-$(CONFIG_SENSORS_MENF21BMC_HWMON) += menf21bmc_hwmon.o
+ obj-$(CONFIG_SENSORS_MR75203)	+= mr75203.o
+--- /dev/null
++++ b/drivers/hwmon/tps23861.c
+@@ -0,0 +1,601 @@
++// SPDX-License-Identifier: GPL-2.0-only
++/*
++ * Copyright (c) 2020 Sartura Ltd.
++ *
++ * Driver for the TI TPS23861 PoE PSE.
++ *
++ * Author: Robert Marko <robert.marko@sartura.hr>
++ */
++
++#include <linux/bitfield.h>
++#include <linux/debugfs.h>
++#include <linux/delay.h>
++#include <linux/hwmon-sysfs.h>
++#include <linux/hwmon.h>
++#include <linux/i2c.h>
++#include <linux/module.h>
++#include <linux/of_device.h>
++#include <linux/regmap.h>
++
++#define TEMPERATURE			0x2c
++#define INPUT_VOLTAGE_LSB		0x2e
++#define INPUT_VOLTAGE_MSB		0x2f
++#define PORT_1_CURRENT_LSB		0x30
++#define PORT_1_CURRENT_MSB		0x31
++#define PORT_1_VOLTAGE_LSB		0x32
++#define PORT_1_VOLTAGE_MSB		0x33
++#define PORT_2_CURRENT_LSB		0x34
++#define PORT_2_CURRENT_MSB		0x35
++#define PORT_2_VOLTAGE_LSB		0x36
++#define PORT_2_VOLTAGE_MSB		0x37
++#define PORT_3_CURRENT_LSB		0x38
++#define PORT_3_CURRENT_MSB		0x39
++#define PORT_3_VOLTAGE_LSB		0x3a
++#define PORT_3_VOLTAGE_MSB		0x3b
++#define PORT_4_CURRENT_LSB		0x3c
++#define PORT_4_CURRENT_MSB		0x3d
++#define PORT_4_VOLTAGE_LSB		0x3e
++#define PORT_4_VOLTAGE_MSB		0x3f
++#define PORT_N_CURRENT_LSB_OFFSET	0x04
++#define PORT_N_VOLTAGE_LSB_OFFSET	0x04
++#define VOLTAGE_CURRENT_MASK		GENMASK(13, 0)
++#define PORT_1_RESISTANCE_LSB		0x60
++#define PORT_1_RESISTANCE_MSB		0x61
++#define PORT_2_RESISTANCE_LSB		0x62
++#define PORT_2_RESISTANCE_MSB		0x63
++#define PORT_3_RESISTANCE_LSB		0x64
++#define PORT_3_RESISTANCE_MSB		0x65
++#define PORT_4_RESISTANCE_LSB		0x66
++#define PORT_4_RESISTANCE_MSB		0x67
++#define PORT_N_RESISTANCE_LSB_OFFSET	0x02
++#define PORT_RESISTANCE_MASK		GENMASK(13, 0)
++#define PORT_RESISTANCE_RSN_MASK	GENMASK(15, 14)
++#define PORT_RESISTANCE_RSN_OTHER	0
++#define PORT_RESISTANCE_RSN_LOW		1
++#define PORT_RESISTANCE_RSN_OPEN	2
++#define PORT_RESISTANCE_RSN_SHORT	3
++#define PORT_1_STATUS			0x0c
++#define PORT_2_STATUS			0x0d
++#define PORT_3_STATUS			0x0e
++#define PORT_4_STATUS			0x0f
++#define PORT_STATUS_CLASS_MASK		GENMASK(7, 4)
++#define PORT_STATUS_DETECT_MASK		GENMASK(3, 0)
++#define PORT_CLASS_UNKNOWN		0
++#define PORT_CLASS_1			1
++#define PORT_CLASS_2			2
++#define PORT_CLASS_3			3
++#define PORT_CLASS_4			4
++#define PORT_CLASS_RESERVED		5
++#define PORT_CLASS_0			6
++#define PORT_CLASS_OVERCURRENT		7
++#define PORT_CLASS_MISMATCH		8
++#define PORT_DETECT_UNKNOWN		0
++#define PORT_DETECT_SHORT		1
++#define PORT_DETECT_RESERVED		2
++#define PORT_DETECT_RESISTANCE_LOW	3
++#define PORT_DETECT_RESISTANCE_OK	4
++#define PORT_DETECT_RESISTANCE_HIGH	5
++#define PORT_DETECT_OPEN_CIRCUIT	6
++#define PORT_DETECT_RESERVED_2		7
++#define PORT_DETECT_MOSFET_FAULT	8
++#define PORT_DETECT_LEGACY		9
++/* Measurment beyond clamp voltage */
++#define PORT_DETECT_CAPACITANCE_INVALID_BEYOND	10
++/* Insufficient voltage delta */
++#define PORT_DETECT_CAPACITANCE_INVALID_DELTA	11
++#define PORT_DETECT_CAPACITANCE_OUT_OF_RANGE	12
++#define POE_PLUS			0x40
++#define OPERATING_MODE			0x12
++#define OPERATING_MODE_OFF		0
++#define OPERATING_MODE_MANUAL		1
++#define OPERATING_MODE_SEMI		2
++#define OPERATING_MODE_AUTO		3
++#define OPERATING_MODE_PORT_1_MASK	GENMASK(1, 0)
++#define OPERATING_MODE_PORT_2_MASK	GENMASK(3, 2)
++#define OPERATING_MODE_PORT_3_MASK	GENMASK(5, 4)
++#define OPERATING_MODE_PORT_4_MASK	GENMASK(7, 6)
++
++#define DETECT_CLASS_RESTART		0x18
++#define POWER_ENABLE			0x19
++#define TPS23861_NUM_PORTS		4
++
++#define TEMPERATURE_LSB			652 /* 0.652 degrees Celsius */
++#define VOLTAGE_LSB			3662 /* 3.662 mV */
++#define SHUNT_RESISTOR_DEFAULT		255000 /* 255 mOhm */
++#define CURRENT_LSB_255			62260 /* 62.260 uA */
++#define CURRENT_LSB_250			61039 /* 61.039 uA */
++#define RESISTANCE_LSB			110966 /* 11.0966 Ohm*/
++#define RESISTANCE_LSB_LOW		157216 /* 15.7216 Ohm*/
++
++struct tps23861_data {
++	struct regmap *regmap;
++	u32 shunt_resistor;
++	struct i2c_client *client;
++	struct dentry *debugfs_dir;
++};
++
++static struct regmap_config tps23861_regmap_config = {
++	.reg_bits = 8,
++	.val_bits = 8,
++};
++
++static int tps23861_read_temp(struct tps23861_data *data, long *val)
++{
++	unsigned int regval;
++	int err;
++
++	err = regmap_read(data->regmap, TEMPERATURE, &regval);
++	if (err < 0)
++		return err;
++
++	*val = (regval * TEMPERATURE_LSB) - 20000;
++
++	return 0;
++}
++
++static int tps23861_read_voltage(struct tps23861_data *data, int channel,
++				 long *val)
++{
++	unsigned int regval;
++	int err;
++
++	if (channel < TPS23861_NUM_PORTS) {
++		err = regmap_bulk_read(data->regmap,
++				       PORT_1_VOLTAGE_LSB + channel * PORT_N_VOLTAGE_LSB_OFFSET,
++				       &regval, 2);
++	} else {
++		err = regmap_bulk_read(data->regmap,
++				       INPUT_VOLTAGE_LSB,
++				       &regval, 2);
++	}
++	if (err < 0)
++		return err;
++
++	*val = (FIELD_GET(VOLTAGE_CURRENT_MASK, regval) * VOLTAGE_LSB) / 1000;
++
++	return 0;
++}
++
++static int tps23861_read_current(struct tps23861_data *data, int channel,
++				 long *val)
++{
++	unsigned int current_lsb;
++	unsigned int regval;
++	int err;
++
++	if (data->shunt_resistor == SHUNT_RESISTOR_DEFAULT)
++		current_lsb = CURRENT_LSB_255;
++	else
++		current_lsb = CURRENT_LSB_250;
++
++	err = regmap_bulk_read(data->regmap,
++			       PORT_1_CURRENT_LSB + channel * PORT_N_CURRENT_LSB_OFFSET,
++			       &regval, 2);
++	if (err < 0)
++		return err;
++
++	*val = (FIELD_GET(VOLTAGE_CURRENT_MASK, regval) * current_lsb) / 1000000;
++
++	return 0;
++}
++
++static int tps23861_port_disable(struct tps23861_data *data, int channel)
++{
++	unsigned int regval = 0;
++	int err;
++
++	regval |= BIT(channel + 4);
++	err = regmap_write(data->regmap, POWER_ENABLE, regval);
++
++	return err;
++}
++
++static int tps23861_port_enable(struct tps23861_data *data, int channel)
++{
++	unsigned int regval = 0;
++	int err;
++
++	regval |= BIT(channel);
++	regval |= BIT(channel + 4);
++	err = regmap_write(data->regmap, DETECT_CLASS_RESTART, regval);
++
++	return err;
++}
++
++static umode_t tps23861_is_visible(const void *data, enum hwmon_sensor_types type,
++				   u32 attr, int channel)
++{
++	switch (type) {
++	case hwmon_temp:
++		switch (attr) {
++		case hwmon_temp_input:
++		case hwmon_temp_label:
++			return 0444;
++		default:
++			return 0;
++		}
++	case hwmon_in:
++		switch (attr) {
++		case hwmon_in_input:
++		case hwmon_in_label:
++			return 0444;
++		case hwmon_in_enable:
++			return 0200;
++		default:
++			return 0;
++		}
++	case hwmon_curr:
++		switch (attr) {
++		case hwmon_curr_input:
++		case hwmon_curr_label:
++			return 0444;
++		default:
++			return 0;
++		}
++	default:
++		return 0;
++	}
++}
++
++static int tps23861_write(struct device *dev, enum hwmon_sensor_types type,
++			  u32 attr, int channel, long val)
++{
++	struct tps23861_data *data = dev_get_drvdata(dev);
++	int err;
++
++	switch (type) {
++	case hwmon_in:
++		switch (attr) {
++		case hwmon_in_enable:
++			if (val == 0)
++				err = tps23861_port_disable(data, channel);
++			else if (val == 1)
++				err = tps23861_port_enable(data, channel);
++			else
++				err = -EINVAL;
++			break;
++		default:
++			return -EOPNOTSUPP;
++		}
++		break;
++	default:
++		return -EOPNOTSUPP;
++	}
++
++	return err;
++}
++
++static int tps23861_read(struct device *dev, enum hwmon_sensor_types type,
++			 u32 attr, int channel, long *val)
++{
++	struct tps23861_data *data = dev_get_drvdata(dev);
++	int err;
++
++	switch (type) {
++	case hwmon_temp:
++		switch (attr) {
++		case hwmon_temp_input:
++			err = tps23861_read_temp(data, val);
++			break;
++		default:
++			return -EOPNOTSUPP;
++		}
++		break;
++	case hwmon_in:
++		switch (attr) {
++		case hwmon_in_input:
++			err = tps23861_read_voltage(data, channel, val);
++			break;
++		default:
++			return -EOPNOTSUPP;
++		}
++		break;
++	case hwmon_curr:
++		switch (attr) {
++		case hwmon_curr_input:
++			err = tps23861_read_current(data, channel, val);
++			break;
++		default:
++			return -EOPNOTSUPP;
++		}
++		break;
++	default:
++		return -EOPNOTSUPP;
++	}
++
++	return err;
++}
++
++static const char * const tps23861_port_label[] = {
++	"Port1",
++	"Port2",
++	"Port3",
++	"Port4",
++	"Input",
++};
++
++static int tps23861_read_string(struct device *dev,
++				enum hwmon_sensor_types type,
++				u32 attr, int channel, const char **str)
++{
++	switch (type) {
++	case hwmon_in:
++	case hwmon_curr:
++		*str = tps23861_port_label[channel];
++		break;
++	case hwmon_temp:
++		*str = "Die";
++		break;
++	default:
++		return -EOPNOTSUPP;
++	}
++
++	return 0;
++}
++
++static const struct hwmon_channel_info *tps23861_info[] = {
++	HWMON_CHANNEL_INFO(chip,
++			   HWMON_C_REGISTER_TZ),
++	HWMON_CHANNEL_INFO(temp,
++			   HWMON_T_INPUT | HWMON_T_LABEL),
++	HWMON_CHANNEL_INFO(in,
++			   HWMON_I_INPUT | HWMON_I_ENABLE | HWMON_I_LABEL,
++			   HWMON_I_INPUT | HWMON_I_ENABLE | HWMON_I_LABEL,
++			   HWMON_I_INPUT | HWMON_I_ENABLE | HWMON_I_LABEL,
++			   HWMON_I_INPUT | HWMON_I_ENABLE | HWMON_I_LABEL,
++			   HWMON_I_INPUT | HWMON_I_LABEL),
++	HWMON_CHANNEL_INFO(curr,
++			   HWMON_C_INPUT | HWMON_C_LABEL,
++			   HWMON_C_INPUT | HWMON_C_LABEL,
++			   HWMON_C_INPUT | HWMON_C_LABEL,
++			   HWMON_C_INPUT | HWMON_C_LABEL),
++	NULL
++};
++
++static const struct hwmon_ops tps23861_hwmon_ops = {
++	.is_visible = tps23861_is_visible,
++	.write = tps23861_write,
++	.read = tps23861_read,
++	.read_string = tps23861_read_string,
++};
++
++static const struct hwmon_chip_info tps23861_chip_info = {
++	.ops = &tps23861_hwmon_ops,
++	.info = tps23861_info,
++};
++
++static char *tps23861_port_operating_mode(struct tps23861_data *data, int port)
++{
++	unsigned int regval;
++	int mode;
++
++	regmap_read(data->regmap, OPERATING_MODE, &regval);
++
++	switch (port) {
++	case 1:
++		mode = FIELD_GET(OPERATING_MODE_PORT_1_MASK, regval);
++		break;
++	case 2:
++		mode = FIELD_GET(OPERATING_MODE_PORT_2_MASK, regval);
++		break;
++	case 3:
++		mode = FIELD_GET(OPERATING_MODE_PORT_3_MASK, regval);
++		break;
++	case 4:
++		mode = FIELD_GET(OPERATING_MODE_PORT_4_MASK, regval);
++		break;
++	default:
++		mode = -EINVAL;
++	}
++
++	switch (mode) {
++	case OPERATING_MODE_OFF:
++		return "Off";
++	case OPERATING_MODE_MANUAL:
++		return "Manual";
++	case OPERATING_MODE_SEMI:
++		return "Semi-Auto";
++	case OPERATING_MODE_AUTO:
++		return "Auto";
++	default:
++		return "Invalid";
++	}
++}
++
++static char *tps23861_port_detect_status(struct tps23861_data *data, int port)
++{
++	unsigned int regval;
++
++	regmap_read(data->regmap,
++		    PORT_1_STATUS + (port - 1),
++		    &regval);
++
++	switch (FIELD_GET(PORT_STATUS_DETECT_MASK, regval)) {
++	case PORT_DETECT_UNKNOWN:
++		return "Unknown device";
++	case PORT_DETECT_SHORT:
++		return "Short circuit";
++	case PORT_DETECT_RESISTANCE_LOW:
++		return "Too low resistance";
++	case PORT_DETECT_RESISTANCE_OK:
++		return "Valid resistance";
++	case PORT_DETECT_RESISTANCE_HIGH:
++		return "Too high resistance";
++	case PORT_DETECT_OPEN_CIRCUIT:
++		return "Open circuit";
++	case PORT_DETECT_MOSFET_FAULT:
++		return "MOSFET fault";
++	case PORT_DETECT_LEGACY:
++		return "Legacy device";
++	case PORT_DETECT_CAPACITANCE_INVALID_BEYOND:
++		return "Invalid capacitance, beyond clamp voltage";
++	case PORT_DETECT_CAPACITANCE_INVALID_DELTA:
++		return "Invalid capacitance, insufficient voltage delta";
++	case PORT_DETECT_CAPACITANCE_OUT_OF_RANGE:
++		return "Valid capacitance, outside of legacy range";
++	case PORT_DETECT_RESERVED:
++	case PORT_DETECT_RESERVED_2:
++	default:
++		return "Invalid";
++	}
++}
++
++static char *tps23861_port_class_status(struct tps23861_data *data, int port)
++{
++	unsigned int regval;
++
++	regmap_read(data->regmap,
++		    PORT_1_STATUS + (port - 1),
++		    &regval);
++
++	switch (FIELD_GET(PORT_STATUS_CLASS_MASK, regval)) {
++	case PORT_CLASS_UNKNOWN:
++		return "Unknown";
++	case PORT_CLASS_RESERVED:
++	case PORT_CLASS_0:
++		return "0";
++	case PORT_CLASS_1:
++		return "1";
++	case PORT_CLASS_2:
++		return "2";
++	case PORT_CLASS_3:
++		return "3";
++	case PORT_CLASS_4:
++		return "4";
++	case PORT_CLASS_OVERCURRENT:
++		return "Overcurrent";
++	case PORT_CLASS_MISMATCH:
++		return "Mismatch";
++	default:
++		return "Invalid";
++	}
++}
++
++static char *tps23861_port_poe_plus_status(struct tps23861_data *data, int port)
++{
++	unsigned int regval;
++
++	regmap_read(data->regmap, POE_PLUS, &regval);
++
++	if (BIT(port + 3) & regval)
++		return "Yes";
++	else
++		return "No";
++}
++
++static int tps23861_port_resistance(struct tps23861_data *data, int port)
++{
++	u16 regval;
++
++	regmap_bulk_read(data->regmap,
++			 PORT_1_RESISTANCE_LSB + PORT_N_RESISTANCE_LSB_OFFSET * (port - 1),
++			 &regval,
++			 2);
++
++	switch (FIELD_GET(PORT_RESISTANCE_RSN_MASK, regval)) {
++	case PORT_RESISTANCE_RSN_OTHER:
++		return (FIELD_GET(PORT_RESISTANCE_MASK, regval) * RESISTANCE_LSB) / 10000;
++	case PORT_RESISTANCE_RSN_LOW:
++		return (FIELD_GET(PORT_RESISTANCE_MASK, regval) * RESISTANCE_LSB_LOW) / 10000;
++	case PORT_RESISTANCE_RSN_SHORT:
++	case PORT_RESISTANCE_RSN_OPEN:
++	default:
++		return 0;
++	}
++}
++
++static int tps23861_port_status_show(struct seq_file *s, void *data)
++{
++	struct tps23861_data *priv = s->private;
++	int i;
++
++	for (i = 1; i < TPS23861_NUM_PORTS + 1; i++) {
++		seq_printf(s, "Port: \t\t%d\n", i);
++		seq_printf(s, "Operating mode: %s\n", tps23861_port_operating_mode(priv, i));
++		seq_printf(s, "Detected: \t%s\n", tps23861_port_detect_status(priv, i));
++		seq_printf(s, "Class: \t\t%s\n", tps23861_port_class_status(priv, i));
++		seq_printf(s, "PoE Plus: \t%s\n", tps23861_port_poe_plus_status(priv, i));
++		seq_printf(s, "Resistance: \t%d\n", tps23861_port_resistance(priv, i));
++		seq_putc(s, '\n');
++	}
++
++	return 0;
++}
++
++DEFINE_SHOW_ATTRIBUTE(tps23861_port_status);
++
++static void tps23861_init_debugfs(struct tps23861_data *data)
++{
++	data->debugfs_dir = debugfs_create_dir(data->client->name, NULL);
++
++	debugfs_create_file("port_status",
++			    0400,
++			    data->debugfs_dir,
++			    data,
++			    &tps23861_port_status_fops);
++}
++
++static int tps23861_probe(struct i2c_client *client)
++{
++	struct device *dev = &client->dev;
++	struct tps23861_data *data;
++	struct device *hwmon_dev;
++	u32 shunt_resistor;
++
++	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
++	if (!data)
++		return -ENOMEM;
++
++	data->client = client;
++	i2c_set_clientdata(client, data);
++
++	data->regmap = devm_regmap_init_i2c(client, &tps23861_regmap_config);
++	if (IS_ERR(data->regmap)) {
++		dev_err(dev, "failed to allocate register map\n");
++		return PTR_ERR(data->regmap);
++	}
++
++	if (!of_property_read_u32(dev->of_node, "shunt-resistor-micro-ohms", &shunt_resistor))
++		data->shunt_resistor = shunt_resistor;
++	else
++		data->shunt_resistor = SHUNT_RESISTOR_DEFAULT;
++
++	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
++							 data, &tps23861_chip_info,
++							 NULL);
++	if (IS_ERR(hwmon_dev))
++		return PTR_ERR(hwmon_dev);
++
++	tps23861_init_debugfs(data);
++
++	return 0;
++}
++
++static int tps23861_remove(struct i2c_client *client)
++{
++	struct tps23861_data *data = i2c_get_clientdata(client);
++
++	debugfs_remove_recursive(data->debugfs_dir);
++
++	return 0;
++}
++
++static const struct of_device_id __maybe_unused tps23861_of_match[] = {
++	{ .compatible = "ti,tps23861", },
++	{ },
++};
++MODULE_DEVICE_TABLE(of, tps23861_of_match);
++
++static struct i2c_driver tps23861_driver = {
++	.probe_new		= tps23861_probe,
++	.remove			= tps23861_remove,
++	.driver = {
++		.name		= "tps23861",
++		.of_match_table	= of_match_ptr(tps23861_of_match),
++	},
++};
++module_i2c_driver(tps23861_driver);
++
++MODULE_LICENSE("GPL");
++MODULE_AUTHOR("Robert Marko <robert.marko@sartura.hr>");
++MODULE_DESCRIPTION("TI TPS23861 PoE PSE");
diff --git a/target/linux/generic/backport-5.10/872-v5.13-01-hwmon-tps23861-define-regmap-max-register.patch b/target/linux/generic/backport-5.10/872-v5.13-01-hwmon-tps23861-define-regmap-max-register.patch
new file mode 100644
index 0000000000..f7ed386944
--- /dev/null
+++ b/target/linux/generic/backport-5.10/872-v5.13-01-hwmon-tps23861-define-regmap-max-register.patch
@@ -0,0 +1,29 @@
+From 3d61a7b3a714eb3ef1777e3c576576aca2b85365 Mon Sep 17 00:00:00 2001
+From: Robert Marko <robert.marko@sartura.hr>
+Date: Thu, 10 Jun 2021 00:07:26 +0200
+Subject: [PATCH 2/4] hwmon: (tps23861) define regmap max register
+
+Define the max register address the device supports.
+This allows reading the whole register space via
+regmap debugfs, without it only register 0x0 is visible.
+
+This was forgotten in the original driver commit.
+
+Fixes: fff7b8ab2255 ("hwmon: add Texas Instruments TPS23861 driver")
+Signed-off-by: Robert Marko <robert.marko@sartura.hr>
+Link: https://lore.kernel.org/r/20210609220728.499879-1-robert.marko@sartura.hr
+Signed-off-by: Guenter Roeck <linux@roeck-us.net>
+---
+ drivers/hwmon/tps23861.c | 1 +
+ 1 file changed, 1 insertion(+)
+
+--- a/drivers/hwmon/tps23861.c
++++ b/drivers/hwmon/tps23861.c
+@@ -117,6 +117,7 @@ struct tps23861_data {
+ static struct regmap_config tps23861_regmap_config = {
+ 	.reg_bits = 8,
+ 	.val_bits = 8,
++	.max_register = 0x6f,
+ };
+ 
+ static int tps23861_read_temp(struct tps23861_data *data, long *val)
diff --git a/target/linux/generic/backport-5.10/872-v5.13-02-hwmon-tps23861-set-current-shunt-value.patch b/target/linux/generic/backport-5.10/872-v5.13-02-hwmon-tps23861-set-current-shunt-value.patch
new file mode 100644
index 0000000000..f1051f77d5
--- /dev/null
+++ b/target/linux/generic/backport-5.10/872-v5.13-02-hwmon-tps23861-set-current-shunt-value.patch
@@ -0,0 +1,57 @@
+From 9bca598d4a86e88afb29fdb516c68b2519bd0fb9 Mon Sep 17 00:00:00 2001
+From: Robert Marko <robert.marko@sartura.hr>
+Date: Thu, 10 Jun 2021 00:07:27 +0200
+Subject: [PATCH 3/4] hwmon: (tps23861) set current shunt value
+
+TPS23861 has a configuration bit for setting of the
+current shunt value used on the board.
+Its bit 0 of the General Mask 1 register.
+
+According to the datasheet bit values are:
+0 for 255 mOhm (Default)
+1 for 250 mOhm
+
+So, configure the bit before registering the hwmon
+device according to the value passed in the DTS or
+default one if none is passed.
+
+This caused potentially reading slightly skewed values
+due to max current value being 1.02A when 250mOhm shunt
+is used instead of 1.0A when 255mOhm is used.
+
+Fixes: fff7b8ab2255 ("hwmon: add Texas Instruments TPS23861 driver")
+Signed-off-by: Robert Marko <robert.marko@sartura.hr>
+Link: https://lore.kernel.org/r/20210609220728.499879-2-robert.marko@sartura.hr
+Signed-off-by: Guenter Roeck <linux@roeck-us.net>
+---
+ drivers/hwmon/tps23861.c | 12 ++++++++++++
+ 1 file changed, 12 insertions(+)
+
+--- a/drivers/hwmon/tps23861.c
++++ b/drivers/hwmon/tps23861.c
+@@ -99,6 +99,9 @@
+ #define POWER_ENABLE			0x19
+ #define TPS23861_NUM_PORTS		4
+ 
++#define TPS23861_GENERAL_MASK_1		0x17
++#define TPS23861_CURRENT_SHUNT_MASK	BIT(0)
++
+ #define TEMPERATURE_LSB			652 /* 0.652 degrees Celsius */
+ #define VOLTAGE_LSB			3662 /* 3.662 mV */
+ #define SHUNT_RESISTOR_DEFAULT		255000 /* 255 mOhm */
+@@ -561,6 +564,15 @@ static int tps23861_probe(struct i2c_cli
+ 	else
+ 		data->shunt_resistor = SHUNT_RESISTOR_DEFAULT;
+ 
++	if (data->shunt_resistor == SHUNT_RESISTOR_DEFAULT)
++		regmap_clear_bits(data->regmap,
++				  TPS23861_GENERAL_MASK_1,
++				  TPS23861_CURRENT_SHUNT_MASK);
++	else
++		regmap_set_bits(data->regmap,
++				TPS23861_GENERAL_MASK_1,
++				TPS23861_CURRENT_SHUNT_MASK);
++
+ 	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
+ 							 data, &tps23861_chip_info,
+ 							 NULL);
diff --git a/target/linux/generic/backport-5.10/872-v5.13-03-hwmon-tps23861-correct-shunt-LSB-values.patch b/target/linux/generic/backport-5.10/872-v5.13-03-hwmon-tps23861-correct-shunt-LSB-values.patch
new file mode 100644
index 0000000000..2485d7a0ee
--- /dev/null
+++ b/target/linux/generic/backport-5.10/872-v5.13-03-hwmon-tps23861-correct-shunt-LSB-values.patch
@@ -0,0 +1,34 @@
+From b447e689a26614ce08a431e8000e8a650a63dcb3 Mon Sep 17 00:00:00 2001
+From: Robert Marko <robert.marko@sartura.hr>
+Date: Thu, 10 Jun 2021 00:07:28 +0200
+Subject: [PATCH 4/4] hwmon: (tps23861) correct shunt LSB values
+
+Current shunt LSB values got reversed during in the
+original driver commit.
+
+So, correct the current shunt LSB values according to
+the datasheet.
+
+This caused reading slightly skewed current values.
+
+Fixes: fff7b8ab2255 ("hwmon: add Texas Instruments TPS23861 driver")
+Signed-off-by: Robert Marko <robert.marko@sartura.hr>
+Link: https://lore.kernel.org/r/20210609220728.499879-3-robert.marko@sartura.hr
+Signed-off-by: Guenter Roeck <linux@roeck-us.net>
+---
+ drivers/hwmon/tps23861.c | 4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+--- a/drivers/hwmon/tps23861.c
++++ b/drivers/hwmon/tps23861.c
+@@ -105,8 +105,8 @@
+ #define TEMPERATURE_LSB			652 /* 0.652 degrees Celsius */
+ #define VOLTAGE_LSB			3662 /* 3.662 mV */
+ #define SHUNT_RESISTOR_DEFAULT		255000 /* 255 mOhm */
+-#define CURRENT_LSB_255			62260 /* 62.260 uA */
+-#define CURRENT_LSB_250			61039 /* 61.039 uA */
++#define CURRENT_LSB_250			62260 /* 62.260 uA */
++#define CURRENT_LSB_255			61039 /* 61.039 uA */
+ #define RESISTANCE_LSB			110966 /* 11.0966 Ohm*/
+ #define RESISTANCE_LSB_LOW		157216 /* 15.7216 Ohm*/
+ 
diff --git a/target/linux/generic/backport-5.10/873-v6.0-hwmon-tps23861-fix-byte-order-in-current-and-voltage.patch b/target/linux/generic/backport-5.10/873-v6.0-hwmon-tps23861-fix-byte-order-in-current-and-voltage.patch
new file mode 100644
index 0000000000..45c2d0b4a4
--- /dev/null
+++ b/target/linux/generic/backport-5.10/873-v6.0-hwmon-tps23861-fix-byte-order-in-current-and-voltage.patch
@@ -0,0 +1,66 @@
+From 0eabb1396656f215a5333a9444158b17b0fd3247 Mon Sep 17 00:00:00 2001
+From: Alexandru Gagniuc <mr.nuke.me@gmail.com>
+Date: Wed, 20 Jul 2022 22:22:55 -0500
+Subject: hwmon: (tps23861) fix byte order in current and voltage registers
+
+Trying to use this driver on a big-endian machine results in garbage
+values for voltage and current. The tps23861 registers are little-
+endian, and regmap_read_bulk() does not do byte order conversion. Thus
+on BE machines, the most significant bytes got modified, and were
+trimmed by the VOLTAGE_CURRENT_MASK.
+
+To resolve this use uint16_t values, and convert them to host byte
+order using le16_to_cpu(). This results in correct readings on MIPS.
+
+Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
+Link: https://lore.kernel.org/r/20220721032255.2850647-1-mr.nuke.me@gmail.com
+[groeck: Use __le16 instead of uint16_t]
+Signed-off-by: Guenter Roeck <linux@roeck-us.net>
+---
+ drivers/hwmon/tps23861.c | 14 +++++++++-----
+ 1 file changed, 9 insertions(+), 5 deletions(-)
+
+--- a/drivers/hwmon/tps23861.c
++++ b/drivers/hwmon/tps23861.c
+@@ -140,7 +140,8 @@ static int tps23861_read_temp(struct tps
+ static int tps23861_read_voltage(struct tps23861_data *data, int channel,
+ 				 long *val)
+ {
+-	unsigned int regval;
++	__le16 regval;
++	long raw_val;
+ 	int err;
+ 
+ 	if (channel < TPS23861_NUM_PORTS) {
+@@ -155,7 +156,8 @@ static int tps23861_read_voltage(struct
+ 	if (err < 0)
+ 		return err;
+ 
+-	*val = (FIELD_GET(VOLTAGE_CURRENT_MASK, regval) * VOLTAGE_LSB) / 1000;
++	raw_val = le16_to_cpu(regval);
++	*val = (FIELD_GET(VOLTAGE_CURRENT_MASK, raw_val) * VOLTAGE_LSB) / 1000;
+ 
+ 	return 0;
+ }
+@@ -163,8 +165,9 @@ static int tps23861_read_voltage(struct
+ static int tps23861_read_current(struct tps23861_data *data, int channel,
+ 				 long *val)
+ {
+-	unsigned int current_lsb;
+-	unsigned int regval;
++	long raw_val, current_lsb;
++	__le16 regval;
++
+ 	int err;
+ 
+ 	if (data->shunt_resistor == SHUNT_RESISTOR_DEFAULT)
+@@ -178,7 +181,8 @@ static int tps23861_read_current(struct
+ 	if (err < 0)
+ 		return err;
+ 
+-	*val = (FIELD_GET(VOLTAGE_CURRENT_MASK, regval) * current_lsb) / 1000000;
++	raw_val = le16_to_cpu(regval);
++	*val = (FIELD_GET(VOLTAGE_CURRENT_MASK, raw_val) * current_lsb) / 1000000;
+ 
+ 	return 0;
+ }
diff --git a/target/linux/generic/config-5.10 b/target/linux/generic/config-5.10
index 3d04a17243..b5f29cf547 100644
--- a/target/linux/generic/config-5.10
+++ b/target/linux/generic/config-5.10
@@ -5304,6 +5304,7 @@ CONFIG_SELECT_MEMORY_MODEL=y
 # CONFIG_SENSORS_TMP401 is not set
 # CONFIG_SENSORS_TMP421 is not set
 # CONFIG_SENSORS_TMP513 is not set
+# CONFIG_SENSORS_TPS23861 is not set
 # CONFIG_SENSORS_TPS40422 is not set
 # CONFIG_SENSORS_TPS53679 is not set
 # CONFIG_SENSORS_TSL2550 is not set