// 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 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 */
#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*/
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,
.max_register = 0x6f,
};
static int tps23861_read_temp(struct tps23861_data *data, long *val)
{
unsigned int regval;
int err;
err = regmap_read(data->regmap, TEMPERATURE, ®val);
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)
{
__le16 regval;
long raw_val;
int err;
if (channel < TPS23861_NUM_PORTS) {
err = regmap_bulk_read(data->regmap,
PORT_1_VOLTAGE_LSB + channel * PORT_N_VOLTAGE_LSB_OFFSET,
®val, 2);
} else {
err = regmap_bulk_read(data->regmap,
INPUT_VOLTAGE_LSB,
®val, 2);
}
if (err < 0)
return err;
raw_val = le16_to_cpu(regval);
*val = (FIELD_GET(VOLTAGE_CURRENT_MASK, raw_val) * VOLTAGE_LSB) / 1000;
return 0;
}
static int tps23861_read_current(struct tps23861_data *data, int channel,
long *val)
{
long raw_val, current_lsb;
__le16 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,
®val, 2);
if (err < 0)
return err;
raw_val = le16_to_cpu(regval);
*val = (FIELD_GET(VOLTAGE_CURRENT_MASK, raw_val) * 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 *port_operating_mode_string(uint8_t mode_reg, unsigned int port)
{
unsigned int mode = ~0;
if (port < TPS23861_NUM_PORTS)
mode = (mode_reg >> (2 * port)) & OPERATING_MODE_PORT_1_MASK;
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 *port_detect_status_string(uint8_t status_reg)
{
switch (FIELD_GET(PORT_STATUS_DETECT_MASK, status_reg)) {
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 *port_class_status_string(uint8_t status_reg)
{
switch (FIELD_GET(PORT_STATUS_CLASS_MASK, status_reg)) {
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 *port_poe_plus_status_string(uint8_t poe_plus, unsigned int port)
{
return (BIT(port + 4) & poe_plus) ? "Yes" : "No";
}
static int tps23861_port_resistance(struct tps23861_data *data, int port)
{
unsigned int raw_val;
__le16 regval;
regmap_bulk_read(data->regmap,
PORT_1_RESISTANCE_LSB + PORT_N_RESISTANCE_LSB_OFFSET * port,
®val,
2);
raw_val = le16_to_cpu(regval);
switch (FIELD_GET(PORT_RESISTANCE_RSN_MASK, raw_val)) {
case PORT_RESISTANCE_RSN_OTHER:
return (FIELD_GET(PORT_RESISTANCE_MASK, raw_val) * RESISTANCE_LSB) / 10000;
case PORT_RESISTANCE_RSN_LOW:
return (FIELD_GET(PORT_RESISTANCE_MASK, raw_val) * 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;
unsigned int i, mode, poe_plus, status;
regmap_read(priv->regmap, OPERATING_MODE, &mode);
regmap_read(priv->regmap, POE_PLUS, &poe_plus);
for (i = 0; i < TPS23861_NUM_PORTS; i++) {
regmap_read(priv->regmap, PORT_1_STATUS + i, &status);
seq_printf(s, "Port: \t\t%d\n", i + 1);
seq_printf(s, "Operating mode: %s\n", port_operating_mode_string(mode, i));
seq_printf(s, "Detected: \t%s\n", port_detect_status_string(status));
seq_printf(s, "Class: \t\t%s\n", port_class_status_string(status));
seq_printf(s, "PoE Plus: \t%s\n", port_poe_plus_status_string(poe_plus, 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,
struct device *hwmon_dev)
{
const char *debugfs_name;
debugfs_name = devm_kasprintf(&data->client->dev, GFP_KERNEL, "%s-%s",
data->client->name, dev_name(hwmon_dev));
if (!debugfs_name)
return;
data->debugfs_dir = debugfs_create_dir(debugfs_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;
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);
if (IS_ERR(hwmon_dev))
return PTR_ERR(hwmon_dev);
tps23861_init_debugfs(data, hwmon_dev);
return 0;
}
static void tps23861_remove(struct i2c_client *client)
{
struct tps23861_data *data = i2c_get_clientdata(client);
debugfs_remove_recursive(data->debugfs_dir);
}
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");
