Re: [PATCH v5 2/2] hwmon: Add driver for Texas Instruments TMP512/513 sensor chips

[Guenter Roeck <linux@roeck-us.net>]

On Tue, Oct 22, 2019 at 01:33:23PM +0000, Tremblay, Eric wrote:
> hwmon: Add driver for Texas Instruments TMP512/513 sensor chips.
> 
> TI's TMP512/513 are I2C/SMBus system monitor chips. These chips
> monitor the supply voltage, supply current, power consumption
> and provide one local and up to three (TMP513) remote temperature sensors.
> 
> It has been tested using a TI TMP513 development kit (TMP513EVM)
> 
> Signed-off-by: Eric Tremblay <etremblay@distech-controls.com>

I don't have any code comments. Please address Rob's feedback for the bindings.

Thanks,
Guenter

> ---
>  Documentation/hwmon/tmp513.rst | 102 +++++
>  MAINTAINERS                    |   7 +
>  drivers/hwmon/Kconfig          |  10 +
>  drivers/hwmon/Makefile         |   1 +
>  drivers/hwmon/tmp513.c         | 786 +++++++++++++++++++++++++++++++++
>  5 files changed, 906 insertions(+)
>  create mode 100644 Documentation/hwmon/tmp513.rst
>  create mode 100644 drivers/hwmon/tmp513.c
> 
> diff --git a/Documentation/hwmon/tmp513.rst b/Documentation/hwmon/tmp513.rst
> new file mode 100644
> index 000000000000..24ef5f6081e0
> --- /dev/null
> +++ b/Documentation/hwmon/tmp513.rst
> @@ -0,0 +1,102 @@
> +.. SPDX-License-Identifier: GPL-2.0
> +Kernel driver tmp513
> +====================
> +
> +Supported chips:
> +
> +  * Texas Instruments TMP512
> +
> +    Prefix: 'tmp512'
> +
> +    Datasheet: http://www.ti.com/lit/ds/symlink/tmp512.pdf
> +
> +  * Texas Instruments TMP513
> +
> +    Prefix: 'tmp513'
> +
> +    Datasheet: http://www.ti.com/lit/ds/symlink/tmp513.pdf
> +
> +Authors:
> +
> +	Eric Tremblay <etremblay@distech-controls.com>
> +
> +Description
> +-----------
> +
> +This driver implements support for Texas Instruments TMP512, and TMP513.
> +The TMP512 (dual-channel) and TMP513 (triple-channel) are system monitors that include
> +remote sensors, a local temperature sensor, and a high-side current shunt monitor.
> +These system monitors have the capability of measuring remote temperatures,
> +on-chip temperatures, and system voltage/power/current consumption.
> +
> +The temperatures are measured in degrees Celsius with a range of
> +-40 to + 125 degrees with a resolution of 0.0625 degree C.
> +
> +For hysteresis value, only the first channel is writable. Writing to it
> +will affect all other values since each channels are sharing the same
> +hysteresis value. The hysteresis is in degrees Celsius with a range of
> +0 to 127.5 degrees with a resolution of 0.5 degree.
> +
> +The driver exports the temperature values via the following sysfs files:
> +
> +**temp[1-4]_input**
> +
> +**temp[1-4]_crit**
> +
> +**temp[1-4]_crit_alarm**
> +
> +**temp[1-4]_crit_hyst**
> +
> +The shunt voltage is measured in micro volts. There are four configurable
> +range: 320mV, 160mV, 80mV and 40mV all of them with a resolution of 10 uV.
> +The range depends on the pga gain specified in the device tree
> +with "pga-gain" (default to 8). The range will be equal to pga gain
> +multiply by 40mV.
> +
> +The driver exports the shunt voltage values via the following sysFs files:
> +
> +**in0_input**
> +
> +**in0_lcrit**
> +
> +**in0_lcrit_alarm**
> +
> +**in0_crit**
> +
> +**in0_crit_alarm**
> +
> +The bus voltage is measured in milli volts. There are two configuable
> +range: 32V and 16V both with a resolution of 4mV. It can be configured in the
> +device tree with "bus-voltage-range" (default to 32V);
> +
> +The driver exports the bus voltage values via the following sysFs files:
> +
> +**in0_input**
> +
> +**in0_lcrit**
> +
> +**in0_lcrit_alarm**
> +
> +**in0_crit**
> +
> +**in0_crit_alarm**
> +
> +The power and the currents range and resolution depends on the calibration
> +register value. Those values are calculate by the hardware using those
> +formula:
> +
> +Current = (ShuntVoltage * CalibrationRegister) / 4096
> +Power   = (Current * BusVoltage) / 5000
> +
> +The driver exports the current and power values via the following sysFs files:
> +
> +**curr0_input**
> +
> +**power1_input**
> +
> +**power1_crit**
> +
> +**power1_crit_alarm**
> +
> +The calibration process follow the procedure of the datasheet (without overflow)
> +and depend on the shunt resistor value and the pga_gain value.
> diff --git a/MAINTAINERS b/MAINTAINERS
> index e51a68bf8ca8..daab325b2fe9 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -16374,6 +16374,13 @@ S:	Maintained
>  F:	Documentation/hwmon/tmp401.rst
>  F:	drivers/hwmon/tmp401.c
>  
> +TMP513 HARDWARE MONITOR DRIVER
> +M:	Eric Tremblay <etremblay@distech-controls.com>
> +L:	linux-hwmon@vger.kernel.org
> +S:	Maintained
> +F:	Documentation/hwmon/tmp513.rst
> +F:	drivers/hwmon/tmp513.c
> +
>  TMPFS (SHMEM FILESYSTEM)
>  M:	Hugh Dickins <hughd@google.com>
>  L:	linux-mm@kvack.org
> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
> index 13a6b4afb4b3..926e3c98dbdf 100644
> --- a/drivers/hwmon/Kconfig
> +++ b/drivers/hwmon/Kconfig
> @@ -1709,6 +1709,16 @@ config SENSORS_TMP421
>  	  This driver can also be built as a module. If so, the module
>  	  will be called tmp421.
>  
> +config SENSORS_TMP513
> +	tristate "Texas Instruments TMP513 and compatibles"
> +	depends on I2C
> +	help
> +	  If you say yes here you get support for Texas Instruments TMP512,
> +	  and TMP513 temperature and power supply sensor chips.
> +
> +	  This driver can also be built as a module. If so, the module
> +	  will be called tmp513.
> +
>  config SENSORS_VEXPRESS
>  	tristate "Versatile Express"
>  	depends on VEXPRESS_CONFIG
> diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
> index 40c036ea45e6..762642291914 100644
> --- a/drivers/hwmon/Makefile
> +++ b/drivers/hwmon/Makefile
> @@ -166,6 +166,7 @@ obj-$(CONFIG_SENSORS_TMP103)	+= tmp103.o
>  obj-$(CONFIG_SENSORS_TMP108)	+= tmp108.o
>  obj-$(CONFIG_SENSORS_TMP401)	+= tmp401.o
>  obj-$(CONFIG_SENSORS_TMP421)	+= tmp421.o
> +obj-$(CONFIG_SENSORS_TMP513)	+= tmp513.o
>  obj-$(CONFIG_SENSORS_VEXPRESS)	+= vexpress-hwmon.o
>  obj-$(CONFIG_SENSORS_VIA_CPUTEMP)+= via-cputemp.o
>  obj-$(CONFIG_SENSORS_VIA686A)	+= via686a.o
> diff --git a/drivers/hwmon/tmp513.c b/drivers/hwmon/tmp513.c
> new file mode 100644
> index 000000000000..8829f01822d8
> --- /dev/null
> +++ b/drivers/hwmon/tmp513.c
> @@ -0,0 +1,786 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Driver for Texas Instruments TMP512, TMP513 power monitor chips
> + *
> + * TMP513:
> + * Thermal/Power Management with Triple Remote and
> + * Local Temperature Sensor and Current Shunt Monitor
> + * Datasheet: http://www.ti.com/lit/gpn/tmp513
> + *
> + * TMP512:
> + * Thermal/Power Management with Dual Remote
> + *	and Local Temperature Sensor and Current Shunt Monitor
> + * Datasheet: http://www.ti.com/lit/gpn/tmp512
> + *
> + * Copyright (C) 2019 Eric Tremblay <etremblay@distech-controls.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; version 2 of the License.
> + */
> +
> +#include <linux/err.h>
> +#include <linux/hwmon.h>
> +#include <linux/i2c.h>
> +#include <linux/init.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/regmap.h>
> +#include <linux/slab.h>
> +#include <linux/util_macros.h>
> +
> +// Common register definition
> +#define TMP51X_SHUNT_CONFIG		0x00
> +#define TMP51X_TEMP_CONFIG		0x01
> +#define TMP51X_STATUS			0x02
> +#define TMP51X_SMBUS_ALERT		0x03
> +#define TMP51X_SHUNT_VOLTAGE_RESULT	0x04
> +#define TMP51X_BUS_VOLTAGE_RESULT	0x05
> +#define TMP51X_POWER_RESULT		0x06
> +#define TMP51X_SHUNT_CURRENT_RESULT	0x07
> +#define TMP51X_LOCAL_TEMP_RESULT	0x08
> +#define TMP51X_REMOTE_TEMP_RESULT_1	0x09
> +#define TMP51X_REMOTE_TEMP_RESULT_2	0x0A
> +#define TMP51X_SHUNT_VOLTAGE_H_LIMIT	0x0C
> +#define TMP51X_SHUNT_VOLTAGE_L_LIMIT	0x0D
> +#define TMP51X_BUS_VOLTAGE_H_LIMIT	0x0E
> +#define TMP51X_BUS_VOLTAGE_L_LIMIT	0x0F
> +#define TMP51X_POWER_LIMIT		0x10
> +#define TMP51X_LOCAL_TEMP_LIMIT	0x11
> +#define TMP51X_REMOTE_TEMP_LIMIT_1	0x12
> +#define TMP51X_REMOTE_TEMP_LIMIT_2	0x13
> +#define TMP51X_SHUNT_CALIBRATION	0x15
> +#define TMP51X_N_FACTOR_AND_HYST_1	0x16
> +#define TMP51X_N_FACTOR_2		0x17
> +#define TMP51X_MAN_ID_REG		0xFE
> +#define TMP51X_DEVICE_ID_REG		0xFF
> +
> +// TMP513 specific register definition
> +#define TMP513_REMOTE_TEMP_RESULT_3	0x0B
> +#define TMP513_REMOTE_TEMP_LIMIT_3	0x14
> +#define TMP513_N_FACTOR_3		0x18
> +
> +// Common attrs, and NULL
> +#define TMP51X_MANUFACTURER_ID		0x55FF
> +
> +#define TMP512_DEVICE_ID		0x22FF
> +#define TMP513_DEVICE_ID		0x23FF
> +
> +// Default config
> +#define TMP51X_SHUNT_CONFIG_DEFAULT	0x399F
> +#define TMP51X_SHUNT_VALUE_DEFAULT	1000
> +#define TMP51X_VBUS_MAX_DEFAULT		32
> +#define TMP51X_PGA_DEFAULT		8
> +#define TMP51X_MAX_REGISTER_ADDR	0xFF
> +
> +#define TMP512_TEMP_CONFIG_DEFAULT	0xBF80
> +#define TMP513_TEMP_CONFIG_DEFAULT	0xFF80
> +
> +// Mask and shift
> +#define CURRENT_SENSE_VOLTAGE_320_MASK	0x1800
> +#define CURRENT_SENSE_VOLTAGE_160_MASK	0x1000
> +#define CURRENT_SENSE_VOLTAGE_80_MASK	0x0800
> +#define CURRENT_SENSE_VOLTAGE_40_MASK	0
> +
> +#define TMP51X_BUS_VOLTAGE_MASK		0x2000
> +#define TMP51X_PGA_MASK			0x1800
> +#define TMP51X_NFACTOR_MASK		0xFF00
> +#define TMP51X_HYST_MASK		0x00FF
> +
> +#define TMP51X_BUS_VOLTAGE_SHIFT	3
> +#define TMP51X_TEMP_SHIFT		3
> +
> +// Alarms
> +#define TMP51X_SHUNT_VOLTAGE_H_LIMIT_POS	15
> +#define TMP51X_SHUNT_VOLTAGE_L_LIMIT_POS	14
> +#define TMP51X_BUS_VOLTAGE_H_LIMIT_POS		13
> +#define TMP51X_BUS_VOLTAGE_L_LIMIT_POS		12
> +#define TMP51X_POWER_LIMIT_POS			11
> +#define TMP51X_LOCAL_TEMP_LIMIT_POS		10
> +#define TMP51X_REMOTE_TEMP_LIMIT_1_POS		9
> +#define TMP51X_REMOTE_TEMP_LIMIT_2_POS		8
> +#define TMP513_REMOTE_TEMP_LIMIT_3_POS		7
> +
> +// Max and Min value
> +#define MAX_BUS_VOLTAGE_32_LIMIT	32764
> +#define MAX_BUS_VOLTAGE_16_LIMIT	16382
> +
> +// Max possible value is -256 to +256 but datasheet indicated -40 to 125.
> +#define MAX_TEMP_LIMIT			125000
> +#define MIN_TEMP_LIMIT			-40000
> +
> +#define MAX_NFACTOR			127
> +#define MIN_NFACTOR			-128
> +#define MAX_TEMP_HYST			127500
> +
> +static const u8 TMP51X_TEMP_INPUT[4] = {
> +	TMP51X_LOCAL_TEMP_RESULT,
> +	TMP51X_REMOTE_TEMP_RESULT_1,
> +	TMP51X_REMOTE_TEMP_RESULT_2,
> +	TMP513_REMOTE_TEMP_RESULT_3
> +};
> +
> +static const u8 TMP51X_TEMP_CRIT[4] = {
> +	TMP51X_LOCAL_TEMP_LIMIT,
> +	TMP51X_REMOTE_TEMP_LIMIT_1,
> +	TMP51X_REMOTE_TEMP_LIMIT_2,
> +	TMP513_REMOTE_TEMP_LIMIT_3
> +};
> +
> +static const u8 TMP51X_TEMP_CRIT_ALARM[4] = {
> +	TMP51X_LOCAL_TEMP_LIMIT_POS,
> +	TMP51X_REMOTE_TEMP_LIMIT_1_POS,
> +	TMP51X_REMOTE_TEMP_LIMIT_2_POS,
> +	TMP513_REMOTE_TEMP_LIMIT_3_POS
> +};
> +
> +static const u8 TMP51X_TEMP_CRIT_HYST[4] = {
> +	TMP51X_N_FACTOR_AND_HYST_1,
> +	TMP51X_N_FACTOR_AND_HYST_1,
> +	TMP51X_N_FACTOR_AND_HYST_1,
> +	TMP51X_N_FACTOR_AND_HYST_1
> +};
> +
> +static const u8 TMP51X_IN_INPUT[2] = {
> +	TMP51X_SHUNT_VOLTAGE_RESULT,
> +	TMP51X_BUS_VOLTAGE_RESULT
> +};
> +
> +static const u8 TMP51X_IN_CRIT[2] = {
> +	TMP51X_SHUNT_VOLTAGE_H_LIMIT,
> +	TMP51X_BUS_VOLTAGE_H_LIMIT
> +};
> +
> +static const u8 TMP51X_IN_LCRIT[2] = {
> +	TMP51X_SHUNT_VOLTAGE_L_LIMIT,
> +	TMP51X_BUS_VOLTAGE_L_LIMIT
> +};
> +
> +static const u8 TMP51X_IN_CRIT_ALARM[2] = {
> +	TMP51X_SHUNT_VOLTAGE_H_LIMIT_POS,
> +	TMP51X_BUS_VOLTAGE_H_LIMIT_POS
> +};
> +
> +static const u8 TMP51X_IN_LCRIT_ALARM[2] = {
> +	TMP51X_SHUNT_VOLTAGE_L_LIMIT_POS,
> +	TMP51X_BUS_VOLTAGE_L_LIMIT_POS
> +};
> +
> +static const u8 TMP51X_CURR_INPUT[1] = {
> +	TMP51X_SHUNT_CURRENT_RESULT
> +};
> +
> +static const u8 TMP51X_POWER_INPUT[1] = {
> +	TMP51X_POWER_RESULT
> +};
> +
> +static const u8 TMP51X_POWER_CRIT[1] = {
> +	TMP51X_POWER_LIMIT
> +};
> +
> +static const u8 TMP51X_POWER_CRIT_ALARM[1] = {
> +	TMP51X_POWER_LIMIT_POS
> +};
> +
> +static struct regmap_config tmp51x_regmap_config = {
> +	.reg_bits = 8,
> +	.val_bits = 16,
> +	.max_register = TMP51X_MAX_REGISTER_ADDR,
> +};
> +
> +enum tmp51x_ids {
> +	tmp512, tmp513
> +};
> +
> +struct tmp51x_data {
> +	u16 shunt_config;
> +	u16 pga_gain;
> +	u16 vbus_max;
> +
> +	u16 temp_config;
> +	u8 nfactor[3];
> +
> +	u32 shunt_uohms;
> +
> +	u32 curr_lsb;
> +	u32 pwr_lsb;
> +
> +	enum tmp51x_ids id;
> +	struct regmap *regmap;
> +};
> +
> +// Set the shift based on the gain 8=4, 4=3, 2=2, 1=1
> +static inline u8 tmp51x_get_pga_shift(struct tmp51x_data *data)
> +{
> +	return 5 - ffs(data->pga_gain);
> +}
> +
> +static int tmp51x_get_value(struct tmp51x_data *data, u8 reg, u8 pos,
> +			    unsigned int regval, long *val)
> +{
> +	switch (reg) {
> +	case TMP51X_STATUS:
> +		*val = (regval >> pos) & 1;
> +		break;
> +	case TMP51X_SHUNT_VOLTAGE_RESULT:
> +	case TMP51X_SHUNT_VOLTAGE_H_LIMIT:
> +	case TMP51X_SHUNT_VOLTAGE_L_LIMIT:
> +		/*
> +		 * 2's compliment number shifted by one to four depending
> +		 * on the pga gain setting.
> +		 * 1lsb = 10uV
> +		 */
> +		*val = sign_extend32(regval, 17 - tmp51x_get_pga_shift(data));
> +		*val = DIV_ROUND_CLOSEST(*val, 100);
> +		break;
> +	case TMP51X_BUS_VOLTAGE_RESULT:
> +	case TMP51X_BUS_VOLTAGE_H_LIMIT:
> +	case TMP51X_BUS_VOLTAGE_L_LIMIT:
> +		// 1lsb = 4mV
> +		*val = (regval >> TMP51X_BUS_VOLTAGE_SHIFT) * 4;
> +		break;
> +	case TMP51X_POWER_RESULT:
> +	case TMP51X_POWER_LIMIT:
> +		// Power = (current * BusVoltage) / 5000
> +		*val = regval * data->pwr_lsb;
> +		break;
> +	case TMP51X_SHUNT_CURRENT_RESULT:
> +		// Current = (ShuntVoltage * CalibrationRegister) / 4096
> +		*val = sign_extend32(regval, 16) * data->curr_lsb;
> +		break;
> +	case TMP51X_LOCAL_TEMP_RESULT:
> +	case TMP51X_REMOTE_TEMP_RESULT_1:
> +	case TMP51X_REMOTE_TEMP_RESULT_2:
> +	case TMP513_REMOTE_TEMP_RESULT_3:
> +	case TMP51X_LOCAL_TEMP_LIMIT:
> +	case TMP51X_REMOTE_TEMP_LIMIT_1:
> +	case TMP51X_REMOTE_TEMP_LIMIT_2:
> +	case TMP513_REMOTE_TEMP_LIMIT_3:
> +		// 1lsb = 0.0625 degrees centigrade
> +		*val = sign_extend32(regval, 16) >> TMP51X_TEMP_SHIFT;
> +		*val = DIV_ROUND_CLOSEST(*val * 625, 10);
> +		break;
> +	case TMP51X_N_FACTOR_AND_HYST_1:
> +		// 1lsb = 0.5 degrees centigrade
> +		*val = (regval & TMP51X_HYST_MASK) * 500;
> +		break;
> +	default:
> +		// Programmer goofed
> +		WARN_ON_ONCE(1);
> +		*val = 0;
> +		return -EOPNOTSUPP;
> +	}
> +
> +	return 0;
> +}
> +
> +static int tmp51x_set_value(struct tmp51x_data *data, u8 reg, long val)
> +{
> +	int regval, max_val;
> +	u32 mask = 0;
> +
> +	switch (reg) {
> +	case TMP51X_SHUNT_VOLTAGE_H_LIMIT:
> +	case TMP51X_SHUNT_VOLTAGE_L_LIMIT:
> +		// 1lsb = 10uV
> +		val *= 100;
> +		max_val = U16_MAX >> tmp51x_get_pga_shift(data);
> +		regval = clamp_val(val, -max_val, max_val);
> +		break;
> +	case TMP51X_BUS_VOLTAGE_H_LIMIT:
> +	case TMP51X_BUS_VOLTAGE_L_LIMIT:
> +		// 1lsb = 4mV
> +		max_val = (data->vbus_max == 32) ?
> +			MAX_BUS_VOLTAGE_32_LIMIT : MAX_BUS_VOLTAGE_16_LIMIT;
> +
> +		val = clamp_val(DIV_ROUND_CLOSEST(val, 4), 0, max_val);
> +		regval = val << TMP51X_BUS_VOLTAGE_SHIFT;
> +		break;
> +	case TMP51X_POWER_LIMIT:
> +		regval = clamp_val(DIV_ROUND_CLOSEST(val, data->pwr_lsb), 0,
> +				   U16_MAX);
> +		break;
> +	case TMP51X_LOCAL_TEMP_LIMIT:
> +	case TMP51X_REMOTE_TEMP_LIMIT_1:
> +	case TMP51X_REMOTE_TEMP_LIMIT_2:
> +	case TMP513_REMOTE_TEMP_LIMIT_3:
> +		// 1lsb = 0.0625 degrees centigrade
> +		val = clamp_val(val, MIN_TEMP_LIMIT, MAX_TEMP_LIMIT);
> +		regval = DIV_ROUND_CLOSEST(val * 10, 625) << TMP51X_TEMP_SHIFT;
> +		break;
> +	case TMP51X_N_FACTOR_AND_HYST_1:
> +		// 1lsb = 0.5 degrees centigrade
> +		val = clamp_val(val, 0, MAX_TEMP_HYST);
> +		regval = DIV_ROUND_CLOSEST(val, 500);
> +		mask = TMP51X_HYST_MASK;
> +		break;
> +	default:
> +		// Programmer goofed
> +		WARN_ON_ONCE(1);
> +		return -EOPNOTSUPP;
> +	}
> +
> +	if (mask == 0)
> +		return regmap_write(data->regmap, reg, regval);
> +	else
> +		return regmap_update_bits(data->regmap, reg, mask, regval);
> +}
> +
> +static int tmp51x_read(struct device *dev, enum hwmon_sensor_types type,
> +		       u32 attr, int channel, long *val)
> +{
> +	struct tmp51x_data *data = dev_get_drvdata(dev);
> +	int ret;
> +	u32 regval;
> +	u8 pos = 0, reg = 0;
> +
> +	switch (type) {
> +	case hwmon_temp:
> +		switch (attr) {
> +		case hwmon_temp_input:
> +			reg = TMP51X_TEMP_INPUT[channel];
> +			break;
> +		case hwmon_temp_crit_alarm:
> +			reg = TMP51X_STATUS;
> +			pos = TMP51X_TEMP_CRIT_ALARM[channel];
> +			break;
> +		case hwmon_temp_crit:
> +			reg = TMP51X_TEMP_CRIT[channel];
> +			break;
> +		case hwmon_temp_crit_hyst:
> +			reg = TMP51X_TEMP_CRIT_HYST[channel];
> +			break;
> +		}
> +		break;
> +	case hwmon_in:
> +		switch (attr) {
> +		case hwmon_in_input:
> +			reg = TMP51X_IN_INPUT[channel];
> +			break;
> +		case hwmon_in_lcrit_alarm:
> +			reg = TMP51X_STATUS;
> +			pos = TMP51X_IN_LCRIT_ALARM[channel];
> +			break;
> +		case hwmon_in_crit_alarm:
> +			reg = TMP51X_STATUS;
> +			pos = TMP51X_IN_CRIT_ALARM[channel];
> +			break;
> +		case hwmon_in_lcrit:
> +			reg = TMP51X_IN_LCRIT[channel];
> +			break;
> +		case hwmon_in_crit:
> +			reg = TMP51X_IN_CRIT[channel];
> +			break;
> +		}
> +		break;
> +	case hwmon_curr:
> +		switch (attr) {
> +		case hwmon_curr_input:
> +			reg = TMP51X_CURR_INPUT[channel];
> +			break;
> +		}
> +		break;
> +	case hwmon_power:
> +		switch (attr) {
> +		case hwmon_power_input:
> +			reg = TMP51X_POWER_INPUT[channel];
> +			break;
> +		case hwmon_power_crit_alarm:
> +			reg = TMP51X_STATUS;
> +			pos = TMP51X_POWER_CRIT_ALARM[channel];
> +			break;
> +		case hwmon_power_crit:
> +			reg = TMP51X_POWER_CRIT[channel];
> +			break;
> +		}
> +		break;
> +	default:
> +		break;
> +	}
> +
> +	if (reg == 0)
> +		return -EOPNOTSUPP;
> +
> +	ret = regmap_read(data->regmap, reg, &regval);
> +	if (ret < 0)
> +		return ret;
> +
> +	return tmp51x_get_value(data, reg, pos, regval, val);
> +}
> +
> +static int tmp51x_write(struct device *dev, enum hwmon_sensor_types type,
> +			u32 attr, int channel, long val)
> +{
> +	u8 reg = 0;
> +
> +	switch (type) {
> +	case hwmon_temp:
> +		switch (attr) {
> +		case hwmon_temp_crit:
> +			reg = TMP51X_TEMP_CRIT[channel];
> +			break;
> +		case hwmon_temp_crit_hyst:
> +			reg = TMP51X_TEMP_CRIT_HYST[channel];
> +			break;
> +		}
> +		break;
> +	case hwmon_in:
> +		switch (attr) {
> +		case hwmon_in_lcrit:
> +			reg = TMP51X_IN_LCRIT[channel];
> +			break;
> +		case hwmon_in_crit:
> +			reg = TMP51X_IN_CRIT[channel];
> +			break;
> +		}
> +		break;
> +	case hwmon_power:
> +		switch (attr) {
> +		case hwmon_power_crit:
> +			reg = TMP51X_POWER_CRIT[channel];
> +			break;
> +		}
> +		break;
> +	default:
> +		break;
> +	}
> +
> +	if (reg == 0)
> +		return -EOPNOTSUPP;
> +
> +	return tmp51x_set_value(dev_get_drvdata(dev), reg, val);
> +}
> +
> +static umode_t tmp51x_is_visible(const void *_data,
> +				 enum hwmon_sensor_types type, u32 attr,
> +				 int channel)
> +{
> +	const struct tmp51x_data *data = _data;
> +
> +	switch (type) {
> +	case hwmon_temp:
> +		if (data->id == tmp512 && channel == 4)
> +			return 0;
> +		switch (attr) {
> +		case hwmon_temp_input:
> +		case hwmon_temp_crit_alarm:
> +			return 0444;
> +		case hwmon_temp_crit:
> +			return 0644;
> +		case hwmon_temp_crit_hyst:
> +			if (channel == 0)
> +				return 0644;
> +			return 0444;
> +		}
> +		break;
> +	case hwmon_in:
> +		switch (attr) {
> +		case hwmon_in_input:
> +		case hwmon_in_lcrit_alarm:
> +		case hwmon_in_crit_alarm:
> +			return 0444;
> +		case hwmon_in_lcrit:
> +		case hwmon_in_crit:
> +			return 0644;
> +		}
> +		break;
> +	case hwmon_curr:
> +		switch (attr) {
> +		case hwmon_curr_input:
> +			return 0444;
> +		}
> +		break;
> +	case hwmon_power:
> +		switch (attr) {
> +		case hwmon_power_input:
> +		case hwmon_power_crit_alarm:
> +			return 0444;
> +		case hwmon_power_crit:
> +			return 0644;
> +		}
> +		break;
> +	default:
> +		break;
> +	}
> +	return 0;
> +}
> +
> +static const struct hwmon_channel_info *tmp51x_info[] = {
> +	HWMON_CHANNEL_INFO(temp,
> +			   HWMON_T_INPUT | HWMON_T_CRIT | HWMON_T_CRIT_ALARM |
> +			   HWMON_T_CRIT_HYST,
> +			   HWMON_T_INPUT | HWMON_T_CRIT | HWMON_T_CRIT_ALARM |
> +			   HWMON_T_CRIT_HYST,
> +			   HWMON_T_INPUT | HWMON_T_CRIT | HWMON_T_CRIT_ALARM |
> +			   HWMON_T_CRIT_HYST,
> +			   HWMON_T_INPUT | HWMON_T_CRIT | HWMON_T_CRIT_ALARM |
> +			   HWMON_T_CRIT_HYST),
> +	HWMON_CHANNEL_INFO(in,
> +			   HWMON_I_INPUT | HWMON_I_LCRIT | HWMON_I_LCRIT_ALARM |
> +			   HWMON_I_CRIT | HWMON_I_CRIT_ALARM,
> +			   HWMON_I_INPUT | HWMON_I_LCRIT | HWMON_I_LCRIT_ALARM |
> +			   HWMON_I_CRIT | HWMON_I_CRIT_ALARM),
> +	HWMON_CHANNEL_INFO(curr,
> +			   HWMON_C_INPUT),
> +	HWMON_CHANNEL_INFO(power,
> +			   HWMON_P_INPUT | HWMON_P_CRIT | HWMON_P_CRIT_ALARM),
> +	NULL
> +};
> +
> +static const struct hwmon_ops tmp51x_hwmon_ops = {
> +	.is_visible = tmp51x_is_visible,
> +	.read = tmp51x_read,
> +	.write = tmp51x_write,
> +};
> +
> +static const struct hwmon_chip_info tmp51x_chip_info = {
> +	.ops = &tmp51x_hwmon_ops,
> +	.info = tmp51x_info,
> +};
> +
> +/*
> + * Calibrate the tmp51x following the datasheet method
> + */
> +static int tmp51x_calibrate(struct tmp51x_data *data)
> +{
> +	int vshunt_max = data->pga_gain * 40;
> +	u64 max_curr_ma;
> +	u32 div;
> +
> +	/*
> +	 * If shunt_uohms is equal to 0, the calibration should be set to 0.
> +	 * The consequence will be that the current and power measurement engine
> +	 * of the sensor will not work. Temperature and voltage sensing will
> +	 * continue to work.
> +	 */
> +	if (data->shunt_uohms == 0)
> +		return regmap_write(data->regmap, TMP51X_SHUNT_CALIBRATION, 0);
> +
> +	max_curr_ma = DIV_ROUND_CLOSEST_ULL(vshunt_max * 1000 * 1000,
> +					    data->shunt_uohms);
> +
> +	/*
> +	 * Calculate the minimal bit resolution for the current and the power.
> +	 * Those values will be used during register interpretation.
> +	 */
> +	data->curr_lsb = DIV_ROUND_CLOSEST_ULL(max_curr_ma * 1000, 32767);
> +	data->pwr_lsb = 20 * data->curr_lsb;
> +
> +	div = DIV_ROUND_CLOSEST_ULL(data->curr_lsb * data->shunt_uohms,
> +				    1000 * 1000);
> +
> +	return regmap_write(data->regmap, TMP51X_SHUNT_CALIBRATION,
> +			    DIV_ROUND_CLOSEST(40960, div));
> +}
> +
> +/*
> + * Initialize the configuration and calibration registers.
> + */
> +static int tmp51x_init(struct tmp51x_data *data)
> +{
> +	unsigned int regval;
> +	int ret = regmap_write(data->regmap, TMP51X_SHUNT_CONFIG,
> +			       data->shunt_config);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = regmap_write(data->regmap, TMP51X_TEMP_CONFIG, data->temp_config);
> +	if (ret < 0)
> +		return ret;
> +
> +	// nFactor configuration
> +	ret = regmap_update_bits(data->regmap, TMP51X_N_FACTOR_AND_HYST_1,
> +				 TMP51X_NFACTOR_MASK, data->nfactor[0] << 8);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = regmap_write(data->regmap, TMP51X_N_FACTOR_2,
> +			   data->nfactor[1] << 8);
> +	if (ret < 0)
> +		return ret;
> +
> +	if (data->id == tmp513) {
> +		ret = regmap_write(data->regmap, TMP513_N_FACTOR_3,
> +				   data->nfactor[2] << 8);
> +		if (ret < 0)
> +			return ret;
> +	}
> +
> +	ret = tmp51x_calibrate(data);
> +	if (ret < 0)
> +		return ret;
> +
> +	// Read the status register before using as the datasheet propose
> +	return regmap_read(data->regmap, TMP51X_STATUS, &regval);
> +}
> +
> +static const struct i2c_device_id tmp51x_id[] = {
> +	{ "tmp512", tmp512 },
> +	{ "tmp513", tmp513 },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(i2c, tmp51x_id);
> +
> +static const struct of_device_id tmp51x_of_match[] = {
> +	{
> +		.compatible = "ti,tmp512",
> +		.data = (void *)tmp512
> +	},
> +	{
> +		.compatible = "ti,tmp513",
> +		.data = (void *)tmp513
> +	},
> +	{ },
> +};
> +MODULE_DEVICE_TABLE(of, tmp51x_of_match);
> +
> +static int tmp51x_vbus_max_to_reg(struct device *dev, struct tmp51x_data *data)
> +{
> +	if (data->vbus_max == 32) {
> +		data->shunt_config |= TMP51X_BUS_VOLTAGE_MASK;
> +	} else if (data->vbus_max == 16) {
> +		data->shunt_config &= ~TMP51X_BUS_VOLTAGE_MASK;
> +	} else {
> +		dev_err(dev, "ti,bus-voltage-range-volts is invalid: %u\n",
> +			data->vbus_max);
> +		return -EINVAL;
> +	}
> +	return 0;
> +}
> +
> +static int tmp51x_pga_gain_to_reg(struct device *dev, struct tmp51x_data *data)
> +{
> +	if (data->pga_gain == 8) {
> +		data->shunt_config |= CURRENT_SENSE_VOLTAGE_320_MASK;
> +	} else if (data->pga_gain == 4) {
> +		data->shunt_config |= CURRENT_SENSE_VOLTAGE_160_MASK;
> +	} else if (data->pga_gain == 2) {
> +		data->shunt_config |= CURRENT_SENSE_VOLTAGE_80_MASK;
> +	} else if (data->pga_gain == 1) {
> +		data->shunt_config |= CURRENT_SENSE_VOLTAGE_40_MASK;
> +	} else {
> +		dev_err(dev, "ti,pga-gain is invalid: %u\n", data->pga_gain);
> +		return -EINVAL;
> +	}
> +	return 0;
> +}
> +
> +static int tmp51x_read_properties(struct device *dev, struct tmp51x_data *data)
> +{
> +	int ret;
> +	u8 nfactor[3];
> +	u32 val;
> +
> +	ret = device_property_read_u32(dev, "ti,shunt-resistor-micro-ohms",
> +				       &val);
> +	data->shunt_uohms = (ret >= 0) ? val : TMP51X_SHUNT_VALUE_DEFAULT;
> +
> +	ret = device_property_read_u32(dev, "ti,bus-voltage-range-volts", &val);
> +	data->vbus_max = (ret >= 0) ? val : TMP51X_VBUS_MAX_DEFAULT;
> +	ret = tmp51x_vbus_max_to_reg(dev, data);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = device_property_read_u32(dev, "ti,pga-gain", &val);
> +	data->pga_gain = (ret >= 0) ? val : TMP51X_PGA_DEFAULT;
> +	ret = tmp51x_pga_gain_to_reg(dev, data);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = device_property_read_u8_array(dev, "ti,nfactor", nfactor,
> +					    (data->id == tmp513) ? 3 : 2);
> +	if (ret >= 0)
> +		memcpy(data->nfactor, nfactor, (data->id == tmp513) ? 3 : 2);
> +
> +	// Check if shunt value is compatible with pga-gain
> +	if (data->shunt_uohms > data->pga_gain * 40 * 1000 * 1000) {
> +		dev_err(dev, "shunt-resistor: %u too big for pga_gain: %u\n",
> +			data->shunt_uohms, data->pga_gain);
> +		return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +
> +static void tmp51x_use_default(struct tmp51x_data *data)
> +{
> +	data->vbus_max = TMP51X_VBUS_MAX_DEFAULT;
> +	data->pga_gain = TMP51X_PGA_DEFAULT;
> +	data->shunt_uohms = TMP51X_SHUNT_VALUE_DEFAULT;
> +}
> +
> +static int tmp51x_configure(struct device *dev, struct tmp51x_data *data)
> +{
> +	data->shunt_config = TMP51X_SHUNT_CONFIG_DEFAULT;
> +	data->temp_config = (data->id == tmp513) ?
> +			TMP513_TEMP_CONFIG_DEFAULT : TMP512_TEMP_CONFIG_DEFAULT;
> +
> +	if (dev->of_node)
> +		return tmp51x_read_properties(dev, data);
> +
> +	tmp51x_use_default(data);
> +
> +	return 0;
> +}
> +
> +static int tmp51x_probe(struct i2c_client *client,
> +			const struct i2c_device_id *id)
> +{
> +	struct device *dev = &client->dev;
> +	struct tmp51x_data *data;
> +	struct device *hwmon_dev;
> +	int ret;
> +
> +	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
> +	if (!data)
> +		return -ENOMEM;
> +
> +	if (client->dev.of_node)
> +		data->id = (enum tmp51x_ids)device_get_match_data(&client->dev);
> +	else
> +		data->id = id->driver_data;
> +
> +	ret = tmp51x_configure(dev, data);
> +	if (ret < 0) {
> +		dev_err(dev, "error configuring the device: %d\n", ret);
> +		return ret;
> +	}
> +
> +	data->regmap = devm_regmap_init_i2c(client, &tmp51x_regmap_config);
> +	if (IS_ERR(data->regmap)) {
> +		dev_err(dev, "failed to allocate register map\n");
> +		return PTR_ERR(data->regmap);
> +	}
> +
> +	ret = tmp51x_init(data);
> +	if (ret < 0) {
> +		dev_err(dev, "error configuring the device: %d\n", ret);
> +		return -ENODEV;
> +	}
> +
> +	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
> +							 data,
> +							 &tmp51x_chip_info,
> +							 NULL);
> +	if (IS_ERR(hwmon_dev))
> +		return PTR_ERR(hwmon_dev);
> +
> +	dev_dbg(dev, "power monitor %s\n", id->name);
> +
> +	return 0;
> +}
> +
> +static struct i2c_driver tmp51x_driver = {
> +	.driver = {
> +		.name	= "tmp51x",
> +		.of_match_table = of_match_ptr(tmp51x_of_match),
> +	},
> +	.probe		= tmp51x_probe,
> +	.id_table	= tmp51x_id,
> +};
> +
> +module_i2c_driver(tmp51x_driver);
> +
> +MODULE_AUTHOR("Eric Tremblay <etremblay@distechcontrols.com>");
> +MODULE_DESCRIPTION("tmp51x driver");
> +MODULE_LICENSE("GPL");