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[v3,3/4] hwmon: smpro: Add Ampere's Altra smpro-hwmon driver

Message ID 20210409031332.21919-4-quan@os.amperecomputing.com (mailing list archive)
State Changes Requested
Headers show
Series Add Ampere's Altra SMPro hwmon driver | expand

Commit Message

Quan Nguyen April 9, 2021, 3:13 a.m. UTC
This commit adds support for Ampere SMpro hwmon driver. This driver
supports accessing various CPU sensors provided by the SMpro co-processor
including temperature, power, voltages, and current.

Signed-off-by: Quan Nguyen <quan@os.amperecomputing.com>
---
 drivers/hwmon/Kconfig       |   8 +
 drivers/hwmon/Makefile      |   1 +
 drivers/hwmon/smpro-hwmon.c | 491 ++++++++++++++++++++++++++++++++++++
 3 files changed, 500 insertions(+)
 create mode 100644 drivers/hwmon/smpro-hwmon.c

Comments

Guenter Roeck April 14, 2021, 12:33 p.m. UTC | #1
On Fri, Apr 09, 2021 at 10:13:31AM +0700, Quan Nguyen wrote:
> This commit adds support for Ampere SMpro hwmon driver. This driver
> supports accessing various CPU sensors provided by the SMpro co-processor
> including temperature, power, voltages, and current.
> 
> Signed-off-by: Quan Nguyen <quan@os.amperecomputing.com>
> ---

Change log goes here. You are making it difficult to review your patches.

>  drivers/hwmon/Kconfig       |   8 +
>  drivers/hwmon/Makefile      |   1 +
>  drivers/hwmon/smpro-hwmon.c | 491 ++++++++++++++++++++++++++++++++++++
>  3 files changed, 500 insertions(+)
>  create mode 100644 drivers/hwmon/smpro-hwmon.c
> 
> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
> index 0ddc974b102e..ba4b5a911baf 100644
> --- a/drivers/hwmon/Kconfig
> +++ b/drivers/hwmon/Kconfig
> @@ -67,6 +67,14 @@ config SENSORS_ABITUGURU3
>  	  This driver can also be built as a module. If so, the module
>  	  will be called abituguru3.
>  
> +config SENSORS_SMPRO
> +	tristate "Ampere's Altra SMpro hardware monitoring driver"
> +	depends on MFD_SMPRO
> +	help
> +	  If you say yes here you get support for the thermal, voltage,
> +	  current and power sensors of Ampere's Altra processor family SoC
> +	  with SMpro co-processor.
> +
>  config SENSORS_AD7314
>  	tristate "Analog Devices AD7314 and compatibles"
>  	depends on SPI
> diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
> index 59e78bc212cf..b25391f9c651 100644
> --- a/drivers/hwmon/Makefile
> +++ b/drivers/hwmon/Makefile
> @@ -174,6 +174,7 @@ obj-$(CONFIG_SENSORS_SHT3x)	+= sht3x.o
>  obj-$(CONFIG_SENSORS_SHTC1)	+= shtc1.o
>  obj-$(CONFIG_SENSORS_SIS5595)	+= sis5595.o
>  obj-$(CONFIG_SENSORS_SMM665)	+= smm665.o
> +obj-$(CONFIG_SENSORS_SMPRO)	+= smpro-hwmon.o
>  obj-$(CONFIG_SENSORS_SMSC47B397)+= smsc47b397.o
>  obj-$(CONFIG_SENSORS_SMSC47M1)	+= smsc47m1.o
>  obj-$(CONFIG_SENSORS_SMSC47M192)+= smsc47m192.o
> diff --git a/drivers/hwmon/smpro-hwmon.c b/drivers/hwmon/smpro-hwmon.c
> new file mode 100644
> index 000000000000..a3389fcbad82
> --- /dev/null
> +++ b/drivers/hwmon/smpro-hwmon.c
> @@ -0,0 +1,491 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Ampere Computing SoC's SMPro Hardware Monitoring Driver
> + *
> + * Copyright (c) 2021, Ampere Computing LLC
> + */
> +#include <linux/bitfield.h>
> +#include <linux/bitops.h>
> +#include <linux/hwmon.h>
> +#include <linux/hwmon-sysfs.h>
> +#include <linux/kernel.h>
> +#include <linux/mod_devicetable.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/property.h>
> +#include <linux/regmap.h>
> +
> +/* Identification Registers */
> +#define MANUFACTURER_ID_REG	0x02
> +#define AMPERE_MANUFACTURER_ID	0xCD3A
> +
> +/* Logical Power Sensor Registers */
> +#define SOC_TEMP		0x00
> +#define SOC_VRD_TEMP		0x01
> +#define DIMM_VRD_TEMP		0x02
> +#define CORE_VRD_TEMP		0x03
> +#define CH0_DIMM_TEMP		0x04
> +#define CH1_DIMM_TEMP		0x05
> +#define CH2_DIMM_TEMP		0x06
> +#define CH3_DIMM_TEMP		0x07
> +#define CH4_DIMM_TEMP		0x08
> +#define CH5_DIMM_TEMP		0x09
> +#define CH6_DIMM_TEMP		0x0A
> +#define CH7_DIMM_TEMP		0x0B
> +#define RCA_VRD_TEMP		0x0C
> +
> +#define CORE_VRD_PWR		0x10
> +#define SOC_PWR			0x11
> +#define DIMM_VRD1_PWR		0x12
> +#define DIMM_VRD2_PWR		0x13
> +#define CORE_VRD_PWR_MW		0x16
> +#define SOC_PWR_MW		0x17
> +#define DIMM_VRD1_PWR_MW	0x18
> +#define DIMM_VRD2_PWR_MW	0x19
> +#define RCA_VRD_PWR		0x1A
> +#define RCA_VRD_PWR_MW		0x1B
> +
> +#define MEM_HOT_THRESHOLD	0x22
> +#define SOC_VR_HOT_THRESHOLD	0x23
> +#define CORE_VRD_VOLT		0x24
> +#define SOC_VRD_VOLT		0x25
> +#define DIMM_VRD1_VOLT		0x26
> +#define DIMM_VRD2_VOLT		0x27
> +#define RCA_VRD_VOLT		0x28
> +
> +#define CORE_VRD_CURR		0x29
> +#define SOC_VRD_CURR		0x2A
> +#define DIMM_VRD1_CURR		0x2B
> +#define DIMM_VRD2_CURR		0x2C
> +#define RCA_VRD_CURR		0x2D
> +
> +struct smpro_hwmon {
> +	struct regmap *regmap;
> +	u32 offset;
> +};
> +
> +struct smpro_sensor {
> +	const u8 reg;
> +	const u8 reg_ext;
> +	const char *label;
> +};
> +
> +static const struct smpro_sensor temperature[] = {
> +	{
> +		.reg = SOC_TEMP,
> +		.label = "temp1 SoC"
> +	},
> +	{
> +		.reg = SOC_VRD_TEMP,
> +		.reg_ext = SOC_VR_HOT_THRESHOLD,
> +		.label = "temp2 SoC VRD"
> +	},
> +	{
> +		.reg = DIMM_VRD_TEMP,
> +		.label = "temp3 DIMM VRD"
> +	},
> +	{
> +		.reg = CORE_VRD_TEMP,
> +		.label = "temp4 CORE VRD"
> +	},
> +	{
> +		.reg = CH0_DIMM_TEMP,
> +		.reg_ext = MEM_HOT_THRESHOLD,
> +		.label = "temp5 CH0 DIMM"
> +	},
> +	{
> +		.reg = CH1_DIMM_TEMP,
> +		.reg_ext = MEM_HOT_THRESHOLD,
> +		.label = "temp6 CH1 DIMM"
> +	},
> +	{
> +		.reg = CH2_DIMM_TEMP,
> +		.reg_ext = MEM_HOT_THRESHOLD,
> +		.label = "temp7 CH2 DIMM"
> +	},
> +	{
> +		.reg = CH3_DIMM_TEMP,
> +		.reg_ext = MEM_HOT_THRESHOLD,
> +		.label = "temp8 CH3 DIMM"
> +	},
> +	{
> +		.reg = CH4_DIMM_TEMP,
> +		.reg_ext = MEM_HOT_THRESHOLD,
> +		.label = "temp9 CH4 DIMM"
> +	},
> +	{
> +		.reg = CH5_DIMM_TEMP,
> +		.reg_ext = MEM_HOT_THRESHOLD,
> +		.label = "temp10 CH5 DIMM"
> +	},
> +	{
> +		.reg = CH6_DIMM_TEMP,
> +		.reg_ext = MEM_HOT_THRESHOLD,
> +		.label = "temp11 CH6 DIMM"
> +	},
> +	{
> +		.reg = CH7_DIMM_TEMP,
> +		.reg_ext = MEM_HOT_THRESHOLD,
> +		.label = "temp12 CH7 DIMM"
> +	},
> +	{
> +		.reg = RCA_VRD_TEMP,
> +		.label = "temp13 RCA VRD"
> +	},
> +};
> +
> +static const struct smpro_sensor voltage[] = {
> +	{
> +		.reg = CORE_VRD_VOLT,
> +		.label = "vout0 CORE VRD"
> +	},
> +	{
> +		.reg = SOC_VRD_VOLT,
> +		.label = "vout1 SoC VRD"
> +	},
> +	{
> +		.reg = DIMM_VRD1_VOLT,
> +		.label = "vout2 DIMM VRD1"
> +	},
> +	{
> +		.reg = DIMM_VRD2_VOLT,
> +		.label = "vout3 DIMM VRD2"
> +	},
> +	{
> +		.reg = RCA_VRD_VOLT,
> +		.label = "vout4 RCA VRD"
> +	},
> +};
> +
> +static const struct smpro_sensor curr_sensor[] = {
> +	{
> +		.reg = CORE_VRD_CURR,
> +		.label = "iout1 CORE VRD"
> +	},
> +	{
> +		.reg = SOC_VRD_CURR,
> +		.label = "iout2 SoC VRD"
> +	},
> +	{
> +		.reg = DIMM_VRD1_CURR,
> +		.label = "iout3 DIMM VRD1"
> +	},
> +	{
> +		.reg = DIMM_VRD2_CURR,
> +		.label = "iout4 DIMM VRD2"
> +	},
> +	{
> +		.reg = RCA_VRD_CURR,
> +		.label = "iout5 RCA VRD"
> +	},
> +};
> +
> +static const struct smpro_sensor power[] = {
> +	{
> +		.reg = CORE_VRD_PWR,
> +		.reg_ext = CORE_VRD_PWR_MW,
> +		.label = "power1 CORE VRD"
> +	},
> +	{
> +		.reg = SOC_PWR,
> +		.reg_ext = SOC_PWR_MW,
> +		.label = "power2 SoC"
> +	},
> +	{
> +		.reg = DIMM_VRD1_PWR,
> +		.reg_ext = DIMM_VRD1_PWR_MW,
> +		.label = "power3 DIMM VRD1"
> +	},
> +	{
> +		.reg = DIMM_VRD2_PWR,
> +		.reg_ext = DIMM_VRD2_PWR_MW,
> +		.label = "power4 DIMM VRD2"
> +	},
> +	{
> +		.reg = RCA_VRD_PWR,
> +		.reg_ext = RCA_VRD_PWR_MW,
> +		.label = "power5 RCA VRD"
> +	},
> +};
> +
> +static int smpro_read_temp(struct device *dev, u32 attr, int channel, long *val)
> +{
> +	struct smpro_hwmon *hwmon = dev_get_drvdata(dev);
> +	unsigned int value;
> +	int ret;
> +
> +	switch (attr) {
> +	case hwmon_temp_input:
> +		ret = regmap_read(hwmon->regmap, hwmon->offset + temperature[channel].reg, &value);
> +		if (ret)
> +			return ret;
> +		break;
> +	case hwmon_temp_crit:
> +		ret = regmap_read(hwmon->regmap,
> +				  hwmon->offset + temperature[channel].reg_ext, &value);
> +		if (ret)
> +			return ret;
> +		break;
> +	default:
> +		return -EOPNOTSUPP;
> +	}
> +
> +	*val = sign_extend32(value, 8) * 1000;
> +	return 0;
> +}
> +
> +static int smpro_read_in(struct device *dev, u32 attr, int channel, long *val)
> +{
> +	struct smpro_hwmon *hwmon = dev_get_drvdata(dev);
> +	unsigned int value;
> +	int ret;
> +
> +	switch (attr) {
> +	case hwmon_in_input:
> +		ret = regmap_read(hwmon->regmap, hwmon->offset + voltage[channel].reg, &value);
> +		if (ret < 0)
> +			return ret;
> +		/* 15-bit value in 1mV */
> +		*val = value & 0x7fff;
> +		return 0;
> +	default:
> +		return -EOPNOTSUPP;
> +	}
> +}
> +
> +static int smpro_read_curr(struct device *dev, u32 attr, int channel, long *val)
> +{
> +	struct smpro_hwmon *hwmon = dev_get_drvdata(dev);
> +	unsigned int value;
> +	int ret;
> +
> +	switch (attr) {
> +	case hwmon_curr_input:
> +		ret = regmap_read(hwmon->regmap, hwmon->offset + curr_sensor[channel].reg, &value);
> +		if (ret < 0)
> +			return ret;
> +		/* Scale reported by the hardware is 1mA */
> +		*val = value & 0x7fff;
> +		return 0;
> +	default:
> +		return -EOPNOTSUPP;
> +	}
> +}
> +
> +static int smpro_read_power(struct device *dev, u32 attr, int channel, long *val_pwr)
> +{
> +	struct smpro_hwmon *hwmon = dev_get_drvdata(dev);
> +	unsigned int val = 0, val_mw = 0;
> +	int ret;
> +
> +	switch (attr) {
> +	case hwmon_power_input:
> +		ret = regmap_read(hwmon->regmap, hwmon->offset + power[channel].reg, &val);
> +		if (ret)
> +			return ret;
> +
> +		ret = regmap_read(hwmon->regmap, hwmon->offset + power[channel].reg_ext, &val_mw);
> +		if (ret)
> +			return ret;
> +
> +		*val_pwr = val * 1000000 + val_mw * 1000;
> +		return 0;
> +
> +	default:
> +		return -EOPNOTSUPP;
> +	}
> +}
> +
> +static int smpro_read(struct device *dev, enum hwmon_sensor_types type,
> +		      u32 attr, int channel, long *val)
> +{
> +	switch (type) {
> +	case hwmon_temp:
> +		return smpro_read_temp(dev, attr, channel, val);
> +	case hwmon_in:
> +		return smpro_read_in(dev, attr, channel, val);
> +	case hwmon_power:
> +		return smpro_read_power(dev, attr, channel, val);
> +	case hwmon_curr:
> +		return smpro_read_curr(dev, attr, channel, val);
> +	default:
> +		return -EOPNOTSUPP;
> +	}
> +}
> +
> +static int smpro_read_string(struct device *dev, enum hwmon_sensor_types type,
> +			     u32 attr, int channel, const char **str)
> +{
> +	switch (type) {
> +	case hwmon_temp:
> +		switch (attr) {
> +		case hwmon_temp_label:
> +			*str = temperature[channel].label;
> +			return 0;
> +		default:
> +			break;
> +		}
> +		break;
> +
> +	case hwmon_in:
> +		switch (attr) {
> +		case hwmon_in_label:
> +			*str = voltage[channel].label;
> +			return 0;
> +		default:
> +			break;
> +		}
> +		break;
> +
> +	case hwmon_curr:
> +		switch (attr) {
> +		case hwmon_curr_label:
> +			*str = curr_sensor[channel].label;
> +			return 0;
> +		default:
> +			break;
> +		}
> +		break;
> +
> +	case hwmon_power:
> +		switch (attr) {
> +		case hwmon_power_label:
> +			*str = power[channel].label;
> +			return 0;
> +		default:
> +			break;
> +		}
> +		break;
> +	default:
> +		break;
> +	}
> +
> +	return -EOPNOTSUPP;
> +}
> +
> +static umode_t smpro_is_visible(const void *data, enum hwmon_sensor_types type,
> +				u32 attr, int channel)
> +{
> +	const struct smpro_hwmon *hwmon = data;
> +	unsigned int value;
> +	int ret;
> +
> +	switch (type) {
> +	case hwmon_temp:
> +		switch (attr) {
> +		case hwmon_temp_input:
> +		case hwmon_temp_label:
> +		case hwmon_temp_crit:
> +			ret = regmap_read(hwmon->regmap,
> +					  hwmon->offset + temperature[channel].reg, &value);
> +			if (ret || value == 0xFFFF)
> +				return 0;
> +		break;
> +		}
> +	default:
> +		break;
> +	}
> +
> +	return 0444;
> +}
> +
> +static const struct hwmon_channel_info *smpro_info[] = {
> +	HWMON_CHANNEL_INFO(temp,
> +			   HWMON_T_INPUT | HWMON_T_LABEL,
> +			   HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
> +			   HWMON_T_INPUT | HWMON_T_LABEL,
> +			   HWMON_T_INPUT | HWMON_T_LABEL,
> +			   HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
> +			   HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
> +			   HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
> +			   HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
> +			   HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
> +			   HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
> +			   HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
> +			   HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
> +			   HWMON_T_INPUT | HWMON_T_LABEL),
> +	HWMON_CHANNEL_INFO(in,
> +			   HWMON_I_INPUT | HWMON_I_LABEL,
> +			   HWMON_I_INPUT | HWMON_I_LABEL,
> +			   HWMON_I_INPUT | HWMON_I_LABEL,
> +			   HWMON_I_INPUT | HWMON_I_LABEL,
> +			   HWMON_I_INPUT | HWMON_I_LABEL),
> +	HWMON_CHANNEL_INFO(power,
> +			   HWMON_P_INPUT | HWMON_P_LABEL,
> +			   HWMON_P_INPUT | HWMON_P_LABEL,
> +			   HWMON_P_INPUT | HWMON_P_LABEL,
> +			   HWMON_P_INPUT | HWMON_P_LABEL,
> +			   HWMON_P_INPUT | HWMON_P_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,
> +			   HWMON_C_INPUT | HWMON_C_LABEL),
> +	NULL
> +};
> +
> +static const struct hwmon_ops smpro_hwmon_ops = {
> +	.is_visible = smpro_is_visible,
> +	.read = smpro_read,
> +	.read_string = smpro_read_string,
> +};
> +
> +static const struct hwmon_chip_info smpro_chip_info = {
> +	.ops = &smpro_hwmon_ops,
> +	.info = smpro_info,
> +};
> +
> +static int smpro_hwmon_probe(struct platform_device *pdev)
> +{
> +	struct smpro_hwmon *hwmon;
> +	struct device *hwmon_dev;
> +	unsigned int val;
> +	int ret;
> +
> +	hwmon = devm_kzalloc(&pdev->dev, sizeof(struct smpro_hwmon), GFP_KERNEL);
> +	if (!hwmon)
> +		return -ENOMEM;
> +
> +	hwmon->regmap = dev_get_regmap(pdev->dev.parent, NULL);
> +	if (!hwmon->regmap)
> +		return -ENODEV;
> +
> +	ret = device_property_read_u32(&pdev->dev, "reg", &hwmon->offset);
> +	if (ret)
> +		return -EINVAL;
> +
> +	/* Check for valid ID */
> +	ret = regmap_read(hwmon->regmap, MANUFACTURER_ID_REG, &val);
> +	if (ret)
> +		return -EPROBE_DEFER;

This is unacceptable. regmap_read() could return various errors.
An error here might mean that the chip is simply not there, or that
there is some other problem with, say, the i2c controller driver.
The function might, for all we know, even return -ENOMEM.

If this is supposed to mean that the chip is not yet ready, some other
and more specific solution will be needed. -EPROBE_DEFER means that
some other driver needs to be loaded first, not "chip is not ready,
try again later".

Thanks,
Guenter

> +
> +	if (val != AMPERE_MANUFACTURER_ID)
> +		return -ENODEV;
> +
> +	hwmon_dev = devm_hwmon_device_register_with_info(&pdev->dev, "smpro_hwmon",
> +							 hwmon, &smpro_chip_info, NULL);
> +
> +	return PTR_ERR_OR_ZERO(hwmon_dev);
> +}
> +
> +static const struct of_device_id smpro_hwmon_of_match[] = {
> +	{ .compatible = "ampere,ac01-hwmon" },
> +	{}
> +};
> +MODULE_DEVICE_TABLE(of, smpro_hwmon_of_match);
> +
> +static struct platform_driver smpro_hwmon_driver = {
> +	.probe		= smpro_hwmon_probe,
> +	.driver = {
> +		.name	= "smpro-hwmon",
> +		.of_match_table = smpro_hwmon_of_match,
> +	},
> +};
> +
> +module_platform_driver(smpro_hwmon_driver);
> +
> +MODULE_AUTHOR("Thu Nguyen <thu@os.amperecomputing.com>");
> +MODULE_AUTHOR("Quan Nguyen <quan@os.amperecomputing.com>");
> +MODULE_DESCRIPTION("Ampere Altra SMPro hwmon driver");
> +MODULE_LICENSE("GPL v2");
Quan Nguyen April 15, 2021, 4:13 a.m. UTC | #2
On 14/04/2021 19:33, Guenter Roeck wrote:
> On Fri, Apr 09, 2021 at 10:13:31AM +0700, Quan Nguyen wrote:
>> This commit adds support for Ampere SMpro hwmon driver. This driver
>> supports accessing various CPU sensors provided by the SMpro co-processor
>> including temperature, power, voltages, and current.
>>
>> Signed-off-by: Quan Nguyen <quan@os.amperecomputing.com>
>> ---
> 
> Change log goes here. You are making it difficult to review your patches.
> 
Will add changelog here in next version.

>>   drivers/hwmon/Kconfig       |   8 +
>>   drivers/hwmon/Makefile      |   1 +
>>   drivers/hwmon/smpro-hwmon.c | 491 ++++++++++++++++++++++++++++++++++++
>>   3 files changed, 500 insertions(+)
>>   create mode 100644 drivers/hwmon/smpro-hwmon.c
>>
>> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
>> index 0ddc974b102e..ba4b5a911baf 100644
>> --- a/drivers/hwmon/Kconfig
>> +++ b/drivers/hwmon/Kconfig
>> @@ -67,6 +67,14 @@ config SENSORS_ABITUGURU3
>>   	  This driver can also be built as a module. If so, the module
>>   	  will be called abituguru3.
>>   
>> +config SENSORS_SMPRO
>> +	tristate "Ampere's Altra SMpro hardware monitoring driver"
>> +	depends on MFD_SMPRO
>> +	help
>> +	  If you say yes here you get support for the thermal, voltage,
>> +	  current and power sensors of Ampere's Altra processor family SoC
>> +	  with SMpro co-processor.
>> +
>>   config SENSORS_AD7314
>>   	tristate "Analog Devices AD7314 and compatibles"
>>   	depends on SPI
>> diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
>> index 59e78bc212cf..b25391f9c651 100644
>> --- a/drivers/hwmon/Makefile
>> +++ b/drivers/hwmon/Makefile
>> @@ -174,6 +174,7 @@ obj-$(CONFIG_SENSORS_SHT3x)	+= sht3x.o
>>   obj-$(CONFIG_SENSORS_SHTC1)	+= shtc1.o
>>   obj-$(CONFIG_SENSORS_SIS5595)	+= sis5595.o
>>   obj-$(CONFIG_SENSORS_SMM665)	+= smm665.o
>> +obj-$(CONFIG_SENSORS_SMPRO)	+= smpro-hwmon.o
>>   obj-$(CONFIG_SENSORS_SMSC47B397)+= smsc47b397.o
>>   obj-$(CONFIG_SENSORS_SMSC47M1)	+= smsc47m1.o
>>   obj-$(CONFIG_SENSORS_SMSC47M192)+= smsc47m192.o
>> diff --git a/drivers/hwmon/smpro-hwmon.c b/drivers/hwmon/smpro-hwmon.c
>> new file mode 100644
>> index 000000000000..a3389fcbad82
>> --- /dev/null
>> +++ b/drivers/hwmon/smpro-hwmon.c
>> @@ -0,0 +1,491 @@
>> +// SPDX-License-Identifier: GPL-2.0+
>> +/*
>> + * Ampere Computing SoC's SMPro Hardware Monitoring Driver
>> + *
>> + * Copyright (c) 2021, Ampere Computing LLC
>> + */
>> +#include <linux/bitfield.h>
>> +#include <linux/bitops.h>
>> +#include <linux/hwmon.h>
>> +#include <linux/hwmon-sysfs.h>
>> +#include <linux/kernel.h>
>> +#include <linux/mod_devicetable.h>
>> +#include <linux/module.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/property.h>
>> +#include <linux/regmap.h>
>> +
>> +/* Identification Registers */
>> +#define MANUFACTURER_ID_REG	0x02
>> +#define AMPERE_MANUFACTURER_ID	0xCD3A
>> +
>> +/* Logical Power Sensor Registers */
>> +#define SOC_TEMP		0x00
>> +#define SOC_VRD_TEMP		0x01
>> +#define DIMM_VRD_TEMP		0x02
>> +#define CORE_VRD_TEMP		0x03
>> +#define CH0_DIMM_TEMP		0x04
>> +#define CH1_DIMM_TEMP		0x05
>> +#define CH2_DIMM_TEMP		0x06
>> +#define CH3_DIMM_TEMP		0x07
>> +#define CH4_DIMM_TEMP		0x08
>> +#define CH5_DIMM_TEMP		0x09
>> +#define CH6_DIMM_TEMP		0x0A
>> +#define CH7_DIMM_TEMP		0x0B
>> +#define RCA_VRD_TEMP		0x0C
>> +
>> +#define CORE_VRD_PWR		0x10
>> +#define SOC_PWR			0x11
>> +#define DIMM_VRD1_PWR		0x12
>> +#define DIMM_VRD2_PWR		0x13
>> +#define CORE_VRD_PWR_MW		0x16
>> +#define SOC_PWR_MW		0x17
>> +#define DIMM_VRD1_PWR_MW	0x18
>> +#define DIMM_VRD2_PWR_MW	0x19
>> +#define RCA_VRD_PWR		0x1A
>> +#define RCA_VRD_PWR_MW		0x1B
>> +
>> +#define MEM_HOT_THRESHOLD	0x22
>> +#define SOC_VR_HOT_THRESHOLD	0x23
>> +#define CORE_VRD_VOLT		0x24
>> +#define SOC_VRD_VOLT		0x25
>> +#define DIMM_VRD1_VOLT		0x26
>> +#define DIMM_VRD2_VOLT		0x27
>> +#define RCA_VRD_VOLT		0x28
>> +
>> +#define CORE_VRD_CURR		0x29
>> +#define SOC_VRD_CURR		0x2A
>> +#define DIMM_VRD1_CURR		0x2B
>> +#define DIMM_VRD2_CURR		0x2C
>> +#define RCA_VRD_CURR		0x2D
>> +
>> +struct smpro_hwmon {
>> +	struct regmap *regmap;
>> +	u32 offset;
>> +};
>> +
>> +struct smpro_sensor {
>> +	const u8 reg;
>> +	const u8 reg_ext;
>> +	const char *label;
>> +};
>> +
>> +static const struct smpro_sensor temperature[] = {
>> +	{
>> +		.reg = SOC_TEMP,
>> +		.label = "temp1 SoC"
>> +	},
>> +	{
>> +		.reg = SOC_VRD_TEMP,
>> +		.reg_ext = SOC_VR_HOT_THRESHOLD,
>> +		.label = "temp2 SoC VRD"
>> +	},
>> +	{
>> +		.reg = DIMM_VRD_TEMP,
>> +		.label = "temp3 DIMM VRD"
>> +	},
>> +	{
>> +		.reg = CORE_VRD_TEMP,
>> +		.label = "temp4 CORE VRD"
>> +	},
>> +	{
>> +		.reg = CH0_DIMM_TEMP,
>> +		.reg_ext = MEM_HOT_THRESHOLD,
>> +		.label = "temp5 CH0 DIMM"
>> +	},
>> +	{
>> +		.reg = CH1_DIMM_TEMP,
>> +		.reg_ext = MEM_HOT_THRESHOLD,
>> +		.label = "temp6 CH1 DIMM"
>> +	},
>> +	{
>> +		.reg = CH2_DIMM_TEMP,
>> +		.reg_ext = MEM_HOT_THRESHOLD,
>> +		.label = "temp7 CH2 DIMM"
>> +	},
>> +	{
>> +		.reg = CH3_DIMM_TEMP,
>> +		.reg_ext = MEM_HOT_THRESHOLD,
>> +		.label = "temp8 CH3 DIMM"
>> +	},
>> +	{
>> +		.reg = CH4_DIMM_TEMP,
>> +		.reg_ext = MEM_HOT_THRESHOLD,
>> +		.label = "temp9 CH4 DIMM"
>> +	},
>> +	{
>> +		.reg = CH5_DIMM_TEMP,
>> +		.reg_ext = MEM_HOT_THRESHOLD,
>> +		.label = "temp10 CH5 DIMM"
>> +	},
>> +	{
>> +		.reg = CH6_DIMM_TEMP,
>> +		.reg_ext = MEM_HOT_THRESHOLD,
>> +		.label = "temp11 CH6 DIMM"
>> +	},
>> +	{
>> +		.reg = CH7_DIMM_TEMP,
>> +		.reg_ext = MEM_HOT_THRESHOLD,
>> +		.label = "temp12 CH7 DIMM"
>> +	},
>> +	{
>> +		.reg = RCA_VRD_TEMP,
>> +		.label = "temp13 RCA VRD"
>> +	},
>> +};
>> +
>> +static const struct smpro_sensor voltage[] = {
>> +	{
>> +		.reg = CORE_VRD_VOLT,
>> +		.label = "vout0 CORE VRD"
>> +	},
>> +	{
>> +		.reg = SOC_VRD_VOLT,
>> +		.label = "vout1 SoC VRD"
>> +	},
>> +	{
>> +		.reg = DIMM_VRD1_VOLT,
>> +		.label = "vout2 DIMM VRD1"
>> +	},
>> +	{
>> +		.reg = DIMM_VRD2_VOLT,
>> +		.label = "vout3 DIMM VRD2"
>> +	},
>> +	{
>> +		.reg = RCA_VRD_VOLT,
>> +		.label = "vout4 RCA VRD"
>> +	},
>> +};
>> +
>> +static const struct smpro_sensor curr_sensor[] = {
>> +	{
>> +		.reg = CORE_VRD_CURR,
>> +		.label = "iout1 CORE VRD"
>> +	},
>> +	{
>> +		.reg = SOC_VRD_CURR,
>> +		.label = "iout2 SoC VRD"
>> +	},
>> +	{
>> +		.reg = DIMM_VRD1_CURR,
>> +		.label = "iout3 DIMM VRD1"
>> +	},
>> +	{
>> +		.reg = DIMM_VRD2_CURR,
>> +		.label = "iout4 DIMM VRD2"
>> +	},
>> +	{
>> +		.reg = RCA_VRD_CURR,
>> +		.label = "iout5 RCA VRD"
>> +	},
>> +};
>> +
>> +static const struct smpro_sensor power[] = {
>> +	{
>> +		.reg = CORE_VRD_PWR,
>> +		.reg_ext = CORE_VRD_PWR_MW,
>> +		.label = "power1 CORE VRD"
>> +	},
>> +	{
>> +		.reg = SOC_PWR,
>> +		.reg_ext = SOC_PWR_MW,
>> +		.label = "power2 SoC"
>> +	},
>> +	{
>> +		.reg = DIMM_VRD1_PWR,
>> +		.reg_ext = DIMM_VRD1_PWR_MW,
>> +		.label = "power3 DIMM VRD1"
>> +	},
>> +	{
>> +		.reg = DIMM_VRD2_PWR,
>> +		.reg_ext = DIMM_VRD2_PWR_MW,
>> +		.label = "power4 DIMM VRD2"
>> +	},
>> +	{
>> +		.reg = RCA_VRD_PWR,
>> +		.reg_ext = RCA_VRD_PWR_MW,
>> +		.label = "power5 RCA VRD"
>> +	},
>> +};
>> +
>> +static int smpro_read_temp(struct device *dev, u32 attr, int channel, long *val)
>> +{
>> +	struct smpro_hwmon *hwmon = dev_get_drvdata(dev);
>> +	unsigned int value;
>> +	int ret;
>> +
>> +	switch (attr) {
>> +	case hwmon_temp_input:
>> +		ret = regmap_read(hwmon->regmap, hwmon->offset + temperature[channel].reg, &value);
>> +		if (ret)
>> +			return ret;
>> +		break;
>> +	case hwmon_temp_crit:
>> +		ret = regmap_read(hwmon->regmap,
>> +				  hwmon->offset + temperature[channel].reg_ext, &value);
>> +		if (ret)
>> +			return ret;
>> +		break;
>> +	default:
>> +		return -EOPNOTSUPP;
>> +	}
>> +
>> +	*val = sign_extend32(value, 8) * 1000;
>> +	return 0;
>> +}
>> +
>> +static int smpro_read_in(struct device *dev, u32 attr, int channel, long *val)
>> +{
>> +	struct smpro_hwmon *hwmon = dev_get_drvdata(dev);
>> +	unsigned int value;
>> +	int ret;
>> +
>> +	switch (attr) {
>> +	case hwmon_in_input:
>> +		ret = regmap_read(hwmon->regmap, hwmon->offset + voltage[channel].reg, &value);
>> +		if (ret < 0)
>> +			return ret;
>> +		/* 15-bit value in 1mV */
>> +		*val = value & 0x7fff;
>> +		return 0;
>> +	default:
>> +		return -EOPNOTSUPP;
>> +	}
>> +}
>> +
>> +static int smpro_read_curr(struct device *dev, u32 attr, int channel, long *val)
>> +{
>> +	struct smpro_hwmon *hwmon = dev_get_drvdata(dev);
>> +	unsigned int value;
>> +	int ret;
>> +
>> +	switch (attr) {
>> +	case hwmon_curr_input:
>> +		ret = regmap_read(hwmon->regmap, hwmon->offset + curr_sensor[channel].reg, &value);
>> +		if (ret < 0)
>> +			return ret;
>> +		/* Scale reported by the hardware is 1mA */
>> +		*val = value & 0x7fff;
>> +		return 0;
>> +	default:
>> +		return -EOPNOTSUPP;
>> +	}
>> +}
>> +
>> +static int smpro_read_power(struct device *dev, u32 attr, int channel, long *val_pwr)
>> +{
>> +	struct smpro_hwmon *hwmon = dev_get_drvdata(dev);
>> +	unsigned int val = 0, val_mw = 0;
>> +	int ret;
>> +
>> +	switch (attr) {
>> +	case hwmon_power_input:
>> +		ret = regmap_read(hwmon->regmap, hwmon->offset + power[channel].reg, &val);
>> +		if (ret)
>> +			return ret;
>> +
>> +		ret = regmap_read(hwmon->regmap, hwmon->offset + power[channel].reg_ext, &val_mw);
>> +		if (ret)
>> +			return ret;
>> +
>> +		*val_pwr = val * 1000000 + val_mw * 1000;
>> +		return 0;
>> +
>> +	default:
>> +		return -EOPNOTSUPP;
>> +	}
>> +}
>> +
>> +static int smpro_read(struct device *dev, enum hwmon_sensor_types type,
>> +		      u32 attr, int channel, long *val)
>> +{
>> +	switch (type) {
>> +	case hwmon_temp:
>> +		return smpro_read_temp(dev, attr, channel, val);
>> +	case hwmon_in:
>> +		return smpro_read_in(dev, attr, channel, val);
>> +	case hwmon_power:
>> +		return smpro_read_power(dev, attr, channel, val);
>> +	case hwmon_curr:
>> +		return smpro_read_curr(dev, attr, channel, val);
>> +	default:
>> +		return -EOPNOTSUPP;
>> +	}
>> +}
>> +
>> +static int smpro_read_string(struct device *dev, enum hwmon_sensor_types type,
>> +			     u32 attr, int channel, const char **str)
>> +{
>> +	switch (type) {
>> +	case hwmon_temp:
>> +		switch (attr) {
>> +		case hwmon_temp_label:
>> +			*str = temperature[channel].label;
>> +			return 0;
>> +		default:
>> +			break;
>> +		}
>> +		break;
>> +
>> +	case hwmon_in:
>> +		switch (attr) {
>> +		case hwmon_in_label:
>> +			*str = voltage[channel].label;
>> +			return 0;
>> +		default:
>> +			break;
>> +		}
>> +		break;
>> +
>> +	case hwmon_curr:
>> +		switch (attr) {
>> +		case hwmon_curr_label:
>> +			*str = curr_sensor[channel].label;
>> +			return 0;
>> +		default:
>> +			break;
>> +		}
>> +		break;
>> +
>> +	case hwmon_power:
>> +		switch (attr) {
>> +		case hwmon_power_label:
>> +			*str = power[channel].label;
>> +			return 0;
>> +		default:
>> +			break;
>> +		}
>> +		break;
>> +	default:
>> +		break;
>> +	}
>> +
>> +	return -EOPNOTSUPP;
>> +}
>> +
>> +static umode_t smpro_is_visible(const void *data, enum hwmon_sensor_types type,
>> +				u32 attr, int channel)
>> +{
>> +	const struct smpro_hwmon *hwmon = data;
>> +	unsigned int value;
>> +	int ret;
>> +
>> +	switch (type) {
>> +	case hwmon_temp:
>> +		switch (attr) {
>> +		case hwmon_temp_input:
>> +		case hwmon_temp_label:
>> +		case hwmon_temp_crit:
>> +			ret = regmap_read(hwmon->regmap,
>> +					  hwmon->offset + temperature[channel].reg, &value);
>> +			if (ret || value == 0xFFFF)
>> +				return 0;
>> +		break;
>> +		}
>> +	default:
>> +		break;
>> +	}
>> +
>> +	return 0444;
>> +}
>> +
>> +static const struct hwmon_channel_info *smpro_info[] = {
>> +	HWMON_CHANNEL_INFO(temp,
>> +			   HWMON_T_INPUT | HWMON_T_LABEL,
>> +			   HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
>> +			   HWMON_T_INPUT | HWMON_T_LABEL,
>> +			   HWMON_T_INPUT | HWMON_T_LABEL,
>> +			   HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
>> +			   HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
>> +			   HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
>> +			   HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
>> +			   HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
>> +			   HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
>> +			   HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
>> +			   HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
>> +			   HWMON_T_INPUT | HWMON_T_LABEL),
>> +	HWMON_CHANNEL_INFO(in,
>> +			   HWMON_I_INPUT | HWMON_I_LABEL,
>> +			   HWMON_I_INPUT | HWMON_I_LABEL,
>> +			   HWMON_I_INPUT | HWMON_I_LABEL,
>> +			   HWMON_I_INPUT | HWMON_I_LABEL,
>> +			   HWMON_I_INPUT | HWMON_I_LABEL),
>> +	HWMON_CHANNEL_INFO(power,
>> +			   HWMON_P_INPUT | HWMON_P_LABEL,
>> +			   HWMON_P_INPUT | HWMON_P_LABEL,
>> +			   HWMON_P_INPUT | HWMON_P_LABEL,
>> +			   HWMON_P_INPUT | HWMON_P_LABEL,
>> +			   HWMON_P_INPUT | HWMON_P_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,
>> +			   HWMON_C_INPUT | HWMON_C_LABEL),
>> +	NULL
>> +};
>> +
>> +static const struct hwmon_ops smpro_hwmon_ops = {
>> +	.is_visible = smpro_is_visible,
>> +	.read = smpro_read,
>> +	.read_string = smpro_read_string,
>> +};
>> +
>> +static const struct hwmon_chip_info smpro_chip_info = {
>> +	.ops = &smpro_hwmon_ops,
>> +	.info = smpro_info,
>> +};
>> +
>> +static int smpro_hwmon_probe(struct platform_device *pdev)
>> +{
>> +	struct smpro_hwmon *hwmon;
>> +	struct device *hwmon_dev;
>> +	unsigned int val;
>> +	int ret;
>> +
>> +	hwmon = devm_kzalloc(&pdev->dev, sizeof(struct smpro_hwmon), GFP_KERNEL);
>> +	if (!hwmon)
>> +		return -ENOMEM;
>> +
>> +	hwmon->regmap = dev_get_regmap(pdev->dev.parent, NULL);
>> +	if (!hwmon->regmap)
>> +		return -ENODEV;
>> +
>> +	ret = device_property_read_u32(&pdev->dev, "reg", &hwmon->offset);
>> +	if (ret)
>> +		return -EINVAL;
>> +
>> +	/* Check for valid ID */
>> +	ret = regmap_read(hwmon->regmap, MANUFACTURER_ID_REG, &val);
>> +	if (ret)
>> +		return -EPROBE_DEFER;
> 
> This is unacceptable. regmap_read() could return various errors.
> An error here might mean that the chip is simply not there, or that
> there is some other problem with, say, the i2c controller driver.
> The function might, for all we know, even return -ENOMEM.
> 
> If this is supposed to mean that the chip is not yet ready, some other
> and more specific solution will be needed. -EPROBE_DEFER means that
> some other driver needs to be loaded first, not "chip is not ready,
> try again later".
> 
> Thanks,
> Guenter
> 

Thanks to this clarification and will return regmap_read() return value, 
ie: "return ret" in next version.

>> +
>> +	if (val != AMPERE_MANUFACTURER_ID)
>> +		return -ENODEV;
>> +
>> +	hwmon_dev = devm_hwmon_device_register_with_info(&pdev->dev, "smpro_hwmon",
>> +							 hwmon, &smpro_chip_info, NULL);
>> +
>> +	return PTR_ERR_OR_ZERO(hwmon_dev);
>> +}
>> +
>> +static const struct of_device_id smpro_hwmon_of_match[] = {
>> +	{ .compatible = "ampere,ac01-hwmon" },
>> +	{}
>> +};
>> +MODULE_DEVICE_TABLE(of, smpro_hwmon_of_match);
>> +
>> +static struct platform_driver smpro_hwmon_driver = {
>> +	.probe		= smpro_hwmon_probe,
>> +	.driver = {
>> +		.name	= "smpro-hwmon",
>> +		.of_match_table = smpro_hwmon_of_match,
>> +	},
>> +};
>> +
>> +module_platform_driver(smpro_hwmon_driver);
>> +
>> +MODULE_AUTHOR("Thu Nguyen <thu@os.amperecomputing.com>");
>> +MODULE_AUTHOR("Quan Nguyen <quan@os.amperecomputing.com>");
>> +MODULE_DESCRIPTION("Ampere Altra SMPro hwmon driver");
>> +MODULE_LICENSE("GPL v2");
diff mbox series

Patch

diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 0ddc974b102e..ba4b5a911baf 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -67,6 +67,14 @@  config SENSORS_ABITUGURU3
 	  This driver can also be built as a module. If so, the module
 	  will be called abituguru3.
 
+config SENSORS_SMPRO
+	tristate "Ampere's Altra SMpro hardware monitoring driver"
+	depends on MFD_SMPRO
+	help
+	  If you say yes here you get support for the thermal, voltage,
+	  current and power sensors of Ampere's Altra processor family SoC
+	  with SMpro co-processor.
+
 config SENSORS_AD7314
 	tristate "Analog Devices AD7314 and compatibles"
 	depends on SPI
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index 59e78bc212cf..b25391f9c651 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -174,6 +174,7 @@  obj-$(CONFIG_SENSORS_SHT3x)	+= sht3x.o
 obj-$(CONFIG_SENSORS_SHTC1)	+= shtc1.o
 obj-$(CONFIG_SENSORS_SIS5595)	+= sis5595.o
 obj-$(CONFIG_SENSORS_SMM665)	+= smm665.o
+obj-$(CONFIG_SENSORS_SMPRO)	+= smpro-hwmon.o
 obj-$(CONFIG_SENSORS_SMSC47B397)+= smsc47b397.o
 obj-$(CONFIG_SENSORS_SMSC47M1)	+= smsc47m1.o
 obj-$(CONFIG_SENSORS_SMSC47M192)+= smsc47m192.o
diff --git a/drivers/hwmon/smpro-hwmon.c b/drivers/hwmon/smpro-hwmon.c
new file mode 100644
index 000000000000..a3389fcbad82
--- /dev/null
+++ b/drivers/hwmon/smpro-hwmon.c
@@ -0,0 +1,491 @@ 
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Ampere Computing SoC's SMPro Hardware Monitoring Driver
+ *
+ * Copyright (c) 2021, Ampere Computing LLC
+ */
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/kernel.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+#include <linux/regmap.h>
+
+/* Identification Registers */
+#define MANUFACTURER_ID_REG	0x02
+#define AMPERE_MANUFACTURER_ID	0xCD3A
+
+/* Logical Power Sensor Registers */
+#define SOC_TEMP		0x00
+#define SOC_VRD_TEMP		0x01
+#define DIMM_VRD_TEMP		0x02
+#define CORE_VRD_TEMP		0x03
+#define CH0_DIMM_TEMP		0x04
+#define CH1_DIMM_TEMP		0x05
+#define CH2_DIMM_TEMP		0x06
+#define CH3_DIMM_TEMP		0x07
+#define CH4_DIMM_TEMP		0x08
+#define CH5_DIMM_TEMP		0x09
+#define CH6_DIMM_TEMP		0x0A
+#define CH7_DIMM_TEMP		0x0B
+#define RCA_VRD_TEMP		0x0C
+
+#define CORE_VRD_PWR		0x10
+#define SOC_PWR			0x11
+#define DIMM_VRD1_PWR		0x12
+#define DIMM_VRD2_PWR		0x13
+#define CORE_VRD_PWR_MW		0x16
+#define SOC_PWR_MW		0x17
+#define DIMM_VRD1_PWR_MW	0x18
+#define DIMM_VRD2_PWR_MW	0x19
+#define RCA_VRD_PWR		0x1A
+#define RCA_VRD_PWR_MW		0x1B
+
+#define MEM_HOT_THRESHOLD	0x22
+#define SOC_VR_HOT_THRESHOLD	0x23
+#define CORE_VRD_VOLT		0x24
+#define SOC_VRD_VOLT		0x25
+#define DIMM_VRD1_VOLT		0x26
+#define DIMM_VRD2_VOLT		0x27
+#define RCA_VRD_VOLT		0x28
+
+#define CORE_VRD_CURR		0x29
+#define SOC_VRD_CURR		0x2A
+#define DIMM_VRD1_CURR		0x2B
+#define DIMM_VRD2_CURR		0x2C
+#define RCA_VRD_CURR		0x2D
+
+struct smpro_hwmon {
+	struct regmap *regmap;
+	u32 offset;
+};
+
+struct smpro_sensor {
+	const u8 reg;
+	const u8 reg_ext;
+	const char *label;
+};
+
+static const struct smpro_sensor temperature[] = {
+	{
+		.reg = SOC_TEMP,
+		.label = "temp1 SoC"
+	},
+	{
+		.reg = SOC_VRD_TEMP,
+		.reg_ext = SOC_VR_HOT_THRESHOLD,
+		.label = "temp2 SoC VRD"
+	},
+	{
+		.reg = DIMM_VRD_TEMP,
+		.label = "temp3 DIMM VRD"
+	},
+	{
+		.reg = CORE_VRD_TEMP,
+		.label = "temp4 CORE VRD"
+	},
+	{
+		.reg = CH0_DIMM_TEMP,
+		.reg_ext = MEM_HOT_THRESHOLD,
+		.label = "temp5 CH0 DIMM"
+	},
+	{
+		.reg = CH1_DIMM_TEMP,
+		.reg_ext = MEM_HOT_THRESHOLD,
+		.label = "temp6 CH1 DIMM"
+	},
+	{
+		.reg = CH2_DIMM_TEMP,
+		.reg_ext = MEM_HOT_THRESHOLD,
+		.label = "temp7 CH2 DIMM"
+	},
+	{
+		.reg = CH3_DIMM_TEMP,
+		.reg_ext = MEM_HOT_THRESHOLD,
+		.label = "temp8 CH3 DIMM"
+	},
+	{
+		.reg = CH4_DIMM_TEMP,
+		.reg_ext = MEM_HOT_THRESHOLD,
+		.label = "temp9 CH4 DIMM"
+	},
+	{
+		.reg = CH5_DIMM_TEMP,
+		.reg_ext = MEM_HOT_THRESHOLD,
+		.label = "temp10 CH5 DIMM"
+	},
+	{
+		.reg = CH6_DIMM_TEMP,
+		.reg_ext = MEM_HOT_THRESHOLD,
+		.label = "temp11 CH6 DIMM"
+	},
+	{
+		.reg = CH7_DIMM_TEMP,
+		.reg_ext = MEM_HOT_THRESHOLD,
+		.label = "temp12 CH7 DIMM"
+	},
+	{
+		.reg = RCA_VRD_TEMP,
+		.label = "temp13 RCA VRD"
+	},
+};
+
+static const struct smpro_sensor voltage[] = {
+	{
+		.reg = CORE_VRD_VOLT,
+		.label = "vout0 CORE VRD"
+	},
+	{
+		.reg = SOC_VRD_VOLT,
+		.label = "vout1 SoC VRD"
+	},
+	{
+		.reg = DIMM_VRD1_VOLT,
+		.label = "vout2 DIMM VRD1"
+	},
+	{
+		.reg = DIMM_VRD2_VOLT,
+		.label = "vout3 DIMM VRD2"
+	},
+	{
+		.reg = RCA_VRD_VOLT,
+		.label = "vout4 RCA VRD"
+	},
+};
+
+static const struct smpro_sensor curr_sensor[] = {
+	{
+		.reg = CORE_VRD_CURR,
+		.label = "iout1 CORE VRD"
+	},
+	{
+		.reg = SOC_VRD_CURR,
+		.label = "iout2 SoC VRD"
+	},
+	{
+		.reg = DIMM_VRD1_CURR,
+		.label = "iout3 DIMM VRD1"
+	},
+	{
+		.reg = DIMM_VRD2_CURR,
+		.label = "iout4 DIMM VRD2"
+	},
+	{
+		.reg = RCA_VRD_CURR,
+		.label = "iout5 RCA VRD"
+	},
+};
+
+static const struct smpro_sensor power[] = {
+	{
+		.reg = CORE_VRD_PWR,
+		.reg_ext = CORE_VRD_PWR_MW,
+		.label = "power1 CORE VRD"
+	},
+	{
+		.reg = SOC_PWR,
+		.reg_ext = SOC_PWR_MW,
+		.label = "power2 SoC"
+	},
+	{
+		.reg = DIMM_VRD1_PWR,
+		.reg_ext = DIMM_VRD1_PWR_MW,
+		.label = "power3 DIMM VRD1"
+	},
+	{
+		.reg = DIMM_VRD2_PWR,
+		.reg_ext = DIMM_VRD2_PWR_MW,
+		.label = "power4 DIMM VRD2"
+	},
+	{
+		.reg = RCA_VRD_PWR,
+		.reg_ext = RCA_VRD_PWR_MW,
+		.label = "power5 RCA VRD"
+	},
+};
+
+static int smpro_read_temp(struct device *dev, u32 attr, int channel, long *val)
+{
+	struct smpro_hwmon *hwmon = dev_get_drvdata(dev);
+	unsigned int value;
+	int ret;
+
+	switch (attr) {
+	case hwmon_temp_input:
+		ret = regmap_read(hwmon->regmap, hwmon->offset + temperature[channel].reg, &value);
+		if (ret)
+			return ret;
+		break;
+	case hwmon_temp_crit:
+		ret = regmap_read(hwmon->regmap,
+				  hwmon->offset + temperature[channel].reg_ext, &value);
+		if (ret)
+			return ret;
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	*val = sign_extend32(value, 8) * 1000;
+	return 0;
+}
+
+static int smpro_read_in(struct device *dev, u32 attr, int channel, long *val)
+{
+	struct smpro_hwmon *hwmon = dev_get_drvdata(dev);
+	unsigned int value;
+	int ret;
+
+	switch (attr) {
+	case hwmon_in_input:
+		ret = regmap_read(hwmon->regmap, hwmon->offset + voltage[channel].reg, &value);
+		if (ret < 0)
+			return ret;
+		/* 15-bit value in 1mV */
+		*val = value & 0x7fff;
+		return 0;
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int smpro_read_curr(struct device *dev, u32 attr, int channel, long *val)
+{
+	struct smpro_hwmon *hwmon = dev_get_drvdata(dev);
+	unsigned int value;
+	int ret;
+
+	switch (attr) {
+	case hwmon_curr_input:
+		ret = regmap_read(hwmon->regmap, hwmon->offset + curr_sensor[channel].reg, &value);
+		if (ret < 0)
+			return ret;
+		/* Scale reported by the hardware is 1mA */
+		*val = value & 0x7fff;
+		return 0;
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int smpro_read_power(struct device *dev, u32 attr, int channel, long *val_pwr)
+{
+	struct smpro_hwmon *hwmon = dev_get_drvdata(dev);
+	unsigned int val = 0, val_mw = 0;
+	int ret;
+
+	switch (attr) {
+	case hwmon_power_input:
+		ret = regmap_read(hwmon->regmap, hwmon->offset + power[channel].reg, &val);
+		if (ret)
+			return ret;
+
+		ret = regmap_read(hwmon->regmap, hwmon->offset + power[channel].reg_ext, &val_mw);
+		if (ret)
+			return ret;
+
+		*val_pwr = val * 1000000 + val_mw * 1000;
+		return 0;
+
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int smpro_read(struct device *dev, enum hwmon_sensor_types type,
+		      u32 attr, int channel, long *val)
+{
+	switch (type) {
+	case hwmon_temp:
+		return smpro_read_temp(dev, attr, channel, val);
+	case hwmon_in:
+		return smpro_read_in(dev, attr, channel, val);
+	case hwmon_power:
+		return smpro_read_power(dev, attr, channel, val);
+	case hwmon_curr:
+		return smpro_read_curr(dev, attr, channel, val);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int smpro_read_string(struct device *dev, enum hwmon_sensor_types type,
+			     u32 attr, int channel, const char **str)
+{
+	switch (type) {
+	case hwmon_temp:
+		switch (attr) {
+		case hwmon_temp_label:
+			*str = temperature[channel].label;
+			return 0;
+		default:
+			break;
+		}
+		break;
+
+	case hwmon_in:
+		switch (attr) {
+		case hwmon_in_label:
+			*str = voltage[channel].label;
+			return 0;
+		default:
+			break;
+		}
+		break;
+
+	case hwmon_curr:
+		switch (attr) {
+		case hwmon_curr_label:
+			*str = curr_sensor[channel].label;
+			return 0;
+		default:
+			break;
+		}
+		break;
+
+	case hwmon_power:
+		switch (attr) {
+		case hwmon_power_label:
+			*str = power[channel].label;
+			return 0;
+		default:
+			break;
+		}
+		break;
+	default:
+		break;
+	}
+
+	return -EOPNOTSUPP;
+}
+
+static umode_t smpro_is_visible(const void *data, enum hwmon_sensor_types type,
+				u32 attr, int channel)
+{
+	const struct smpro_hwmon *hwmon = data;
+	unsigned int value;
+	int ret;
+
+	switch (type) {
+	case hwmon_temp:
+		switch (attr) {
+		case hwmon_temp_input:
+		case hwmon_temp_label:
+		case hwmon_temp_crit:
+			ret = regmap_read(hwmon->regmap,
+					  hwmon->offset + temperature[channel].reg, &value);
+			if (ret || value == 0xFFFF)
+				return 0;
+		break;
+		}
+	default:
+		break;
+	}
+
+	return 0444;
+}
+
+static const struct hwmon_channel_info *smpro_info[] = {
+	HWMON_CHANNEL_INFO(temp,
+			   HWMON_T_INPUT | HWMON_T_LABEL,
+			   HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
+			   HWMON_T_INPUT | HWMON_T_LABEL,
+			   HWMON_T_INPUT | HWMON_T_LABEL,
+			   HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
+			   HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
+			   HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
+			   HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
+			   HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
+			   HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
+			   HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
+			   HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_CRIT,
+			   HWMON_T_INPUT | HWMON_T_LABEL),
+	HWMON_CHANNEL_INFO(in,
+			   HWMON_I_INPUT | HWMON_I_LABEL,
+			   HWMON_I_INPUT | HWMON_I_LABEL,
+			   HWMON_I_INPUT | HWMON_I_LABEL,
+			   HWMON_I_INPUT | HWMON_I_LABEL,
+			   HWMON_I_INPUT | HWMON_I_LABEL),
+	HWMON_CHANNEL_INFO(power,
+			   HWMON_P_INPUT | HWMON_P_LABEL,
+			   HWMON_P_INPUT | HWMON_P_LABEL,
+			   HWMON_P_INPUT | HWMON_P_LABEL,
+			   HWMON_P_INPUT | HWMON_P_LABEL,
+			   HWMON_P_INPUT | HWMON_P_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,
+			   HWMON_C_INPUT | HWMON_C_LABEL),
+	NULL
+};
+
+static const struct hwmon_ops smpro_hwmon_ops = {
+	.is_visible = smpro_is_visible,
+	.read = smpro_read,
+	.read_string = smpro_read_string,
+};
+
+static const struct hwmon_chip_info smpro_chip_info = {
+	.ops = &smpro_hwmon_ops,
+	.info = smpro_info,
+};
+
+static int smpro_hwmon_probe(struct platform_device *pdev)
+{
+	struct smpro_hwmon *hwmon;
+	struct device *hwmon_dev;
+	unsigned int val;
+	int ret;
+
+	hwmon = devm_kzalloc(&pdev->dev, sizeof(struct smpro_hwmon), GFP_KERNEL);
+	if (!hwmon)
+		return -ENOMEM;
+
+	hwmon->regmap = dev_get_regmap(pdev->dev.parent, NULL);
+	if (!hwmon->regmap)
+		return -ENODEV;
+
+	ret = device_property_read_u32(&pdev->dev, "reg", &hwmon->offset);
+	if (ret)
+		return -EINVAL;
+
+	/* Check for valid ID */
+	ret = regmap_read(hwmon->regmap, MANUFACTURER_ID_REG, &val);
+	if (ret)
+		return -EPROBE_DEFER;
+
+	if (val != AMPERE_MANUFACTURER_ID)
+		return -ENODEV;
+
+	hwmon_dev = devm_hwmon_device_register_with_info(&pdev->dev, "smpro_hwmon",
+							 hwmon, &smpro_chip_info, NULL);
+
+	return PTR_ERR_OR_ZERO(hwmon_dev);
+}
+
+static const struct of_device_id smpro_hwmon_of_match[] = {
+	{ .compatible = "ampere,ac01-hwmon" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, smpro_hwmon_of_match);
+
+static struct platform_driver smpro_hwmon_driver = {
+	.probe		= smpro_hwmon_probe,
+	.driver = {
+		.name	= "smpro-hwmon",
+		.of_match_table = smpro_hwmon_of_match,
+	},
+};
+
+module_platform_driver(smpro_hwmon_driver);
+
+MODULE_AUTHOR("Thu Nguyen <thu@os.amperecomputing.com>");
+MODULE_AUTHOR("Quan Nguyen <quan@os.amperecomputing.com>");
+MODULE_DESCRIPTION("Ampere Altra SMPro hwmon driver");
+MODULE_LICENSE("GPL v2");