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Wed, 30 Dec 2020 08:44:53 -0800 (PST) Sender: Guenter Roeck Date: Wed, 30 Dec 2020 08:44:52 -0800 From: Guenter Roeck To: Robert Marko Cc: jdelvare@suse.com, robh+dt@kernel.org, linux-hwmon@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Luka Perkov Subject: Re: [PATCH v3 2/3] hwmon: add Texas Instruments TPS23861 driver Message-ID: <20201230164452.GA103852@roeck-us.net> References: <20201222143012.1618807-1-robert.marko@sartura.hr> <20201222143012.1618807-2-robert.marko@sartura.hr> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201222143012.1618807-2-robert.marko@sartura.hr> User-Agent: Mutt/1.9.4 (2018-02-28) Precedence: bulk List-ID: X-Mailing-List: linux-hwmon@vger.kernel.org On Tue, Dec 22, 2020 at 03:30:11PM +0100, Robert Marko wrote: > Add basic monitoring support as well as port on/off control for Texas > Instruments TPS23861 PoE PSE IC. > > Signed-off-by: Robert Marko > Cc: Luka Perkov > --- > Changes in v3: > * Leave only standard values in hwmon hwmon > * Drop custom sysfs entries > * Use debugfs to provide non standard debug information > * Add temperature label > * Use hwmon_in_enable to enable/disable ports > > Changes in v2: > * Convert to devm_hwmon_device_register_with_info() > * Change license > > drivers/hwmon/Kconfig | 11 + > drivers/hwmon/Makefile | 1 + > drivers/hwmon/tps23861.c | 603 +++++++++++++++++++++++++++++++++++++++ Driver documentation (Documentation/hwmon/tps23861) is missing. > 3 files changed, 615 insertions(+) > create mode 100644 drivers/hwmon/tps23861.c > > diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig > index a850e4f0e0bd..3368ecfa7a9c 100644 > --- 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 > diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile > index 9db2903b61e5..7493e9d5dc43 100644 > --- a/drivers/hwmon/Makefile > +++ b/drivers/hwmon/Makefile > @@ -141,6 +141,7 @@ obj-$(CONFIG_SENSORS_MAX31790) += max31790.o > obj-$(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 > diff --git a/drivers/hwmon/tps23861.c b/drivers/hwmon/tps23861.c > new file mode 100644 > index 000000000000..a321e4700f48 > --- /dev/null > +++ b/drivers/hwmon/tps23861.c > @@ -0,0 +1,603 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Copyright (c) 2020 Sartura Ltd. > + * > + * Driver for the TI TPS23861 PoE PSE. > + * > + * Author: Robert Marko > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#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, ®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) > +{ > + 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, > + ®val, 2); > + } else { > + err = regmap_bulk_read(data->regmap, > + INPUT_VOLTAGE_LSB, > + ®val, 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, > + ®val, 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, ®val); > + > + 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), > + ®val); > + > + 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), > + ®val); > + > + 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, ®val); > + > + 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), > + ®val, > + 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); > + if (!data->debugfs_dir) > + return; Unecessary (and wrongh) error check. debugfs_create_dir() returns an ERR_PTR() on error, not NULL. debugfs_create_file() checks for that error condition, so the check here is unencessary. > + > + 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) < 0) > + data->shunt_resistor = shunt_resistor; > + else > + data->shunt_resistor = SHUNT_RESISTOR_DEFAULT; > + The error condition is wrong; of_property_read_u32() never returns a negative value. Per documentation: "Returns true if the property exists false otherwise" > + 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 "); > +MODULE_DESCRIPTION("TI TPS23861 PoE PSE");