Re: [PATCH 3/4] hwmon: smpro: Add Ampere's Altra smpro-hwmon driver

Quan Nguyen
2021-03-01T12:29:29Z

On 25/02/2021 23:08, Guenter Roeck wrote:
> On 2/25/21 2:18 AM, 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>
>> ---
>> drivers/hwmon/Kconfig | 8 +
>> drivers/hwmon/Makefile | 1 +
>> drivers/hwmon/smpro-hwmon.c | 620 ++++++++++++++++++++++++++++++++++++
>> 3 files changed, 629 insertions(+)
>> create mode 100644 drivers/hwmon/smpro-hwmon.c
>>
>> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
>> index 54f04e61fb83..7b0458bf903c 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 fe38e8a5c979..ac0892540abb 100644
>> --- a/drivers/hwmon/Makefile
>> +++ b/drivers/hwmon/Makefile
>> @@ -173,6 +173,7 @@ 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..d70764ffc78f
>> --- /dev/null
>> +++ b/drivers/hwmon/smpro-hwmon.c
>> @@ -0,0 +1,620 @@
>> +// SPDX-License-Identifier: GPL-2.0+
>> +/*
>> + * Ampere Computing SoC's SMPro Hardware Monitoring Driver
>> + *
>> + * Copyright (c) 2021, Ampere Computing LLC
>> + *
>> + * 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; either version 2 of
>> + * the License, or (at your option) any later version.
>> + *
>> + * This program is distributed in the hope that it will be useful,
>> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
>> + * GNU General Public License for more details.
>> + *
>> + * You should have received a copy of the GNU General Public License
>> + * along with this program; if not, see <http://www.gnu.org/licenses/>.
>
> Repeating the text of GPL is not necessary. This is what
> SPDX-License-Identifier is for.
>
Thanks Guenter,
Wil fix this in next version.

>> + */
>> +#include <linux/bitfield.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
>> +
>> +/* Capability Registers */
>> +#define SOC_TDP_REG 0x0E
>
> This is used to report power. What does it actually report ?
> If it is the design power, it should not be reported as power,
> but possibly as maximum SOC power.
>
> If so, and if other limit registers are reported as actual values,
> please change to report as limits.
>
>> +
>> +/* Logical Power Sensor Registers */
>> +#define SOC_TEMP_REG 0x10
>> +#define SOC_VRD_TEMP_REG 0x11
>> +#define DIMM_VRD_TEMP_REG 0x12
>> +#define CORE_VRD_TEMP_REG 0x13
>> +#define CH0_DIMM_TEMP_REG 0x14
>> +#define CH1_DIMM_TEMP_REG 0x15
>> +#define CH2_DIMM_TEMP_REG 0x16
>> +#define CH3_DIMM_TEMP_REG 0x17
>> +#define CH4_DIMM_TEMP_REG 0x18
>> +#define CH5_DIMM_TEMP_REG 0x19
>> +#define CH6_DIMM_TEMP_REG 0x1A
>> +#define CH7_DIMM_TEMP_REG 0x1B
>> +#define RCA_VRD_TEMP_REG 0x1C
>> +
>> +#define CORE_VRD_PWR_REG 0x20
>> +#define SOC_PWR_REG 0x21
>> +#define DIMM_VRD1_PWR_REG 0x22
>> +#define DIMM_VRD2_PWR_REG 0x23
>> +#define CORE_VRD_PWR_MW_REG 0x26
>> +#define SOC_PWR_MW_REG 0x27
>> +#define DIMM_VRD1_PWR_MW_REG 0x28
>> +#define DIMM_VRD2_PWR_MW_REG 0x29
>> +#define RCA_VRD_PWR_REG 0x2A
>> +#define RCA_VRD_PWR_MW_REG 0x2B
>> +
>> +#define MEM_HOT_THRESHOLD_REG 0x32
>> +#define SOC_VR_HOT_THRESHOLD_REG 0x33
>
> Apparently there _are_ more limit registers.
> Please implement those as limit attributes.
>
Will change in next version

>> +#define CORE_VRD_VOLT_REG 0x34
>> +#define SOC_VRD_VOLT_REG 0x35
>> +#define DIMM_VRD1_VOLT_REG 0x36
>> +#define DIMM_VRD2_VOLT_REG 0x37
>> +#define RCA_VRD_VOLT_REG 0x38
>> +
>> +#define CORE_VRD_CURR_REG 0x39
>> +#define SOC_VRD_CURR_REG 0x3A
>> +#define DIMM_VRD1_CURR_REG 0x3B
>> +#define DIMM_VRD2_CURR_REG 0x3C
>> +#define RCA_VRD_CURR_REG 0x3D
>> +
>> +/* Add for DIMM group */
>> +#define DIMM_GROUP_DUMMY_REG 0xFF
>> +
>> +struct smpro_hwmon {
>> + struct regmap *regmap;
>> +};
>> +
>> +static const u8 temp_regs[] = {
>> + SOC_TEMP_REG,
>> + SOC_VRD_TEMP_REG,
>> + DIMM_VRD_TEMP_REG,
>> + CORE_VRD_TEMP_REG,
>> + /* reserved for DIMM G0 */
>> + DIMM_GROUP_DUMMY_REG,
>> + CH0_DIMM_TEMP_REG,
>> + CH1_DIMM_TEMP_REG,
>> + CH2_DIMM_TEMP_REG,
>> + CH3_DIMM_TEMP_REG,
>> + /* reserved for DIMM G1 */
>> + DIMM_GROUP_DUMMY_REG,
>> + CH4_DIMM_TEMP_REG,
>> + CH5_DIMM_TEMP_REG,
>> + CH6_DIMM_TEMP_REG,
>> + CH7_DIMM_TEMP_REG,
>> + MEM_HOT_THRESHOLD_REG,
>> + SOC_VR_HOT_THRESHOLD_REG,
>> + RCA_VRD_TEMP_REG,
>> +};
>> +
>> +static const u8 volt_regs[] = {
>> + CORE_VRD_VOLT_REG,
>> + SOC_VRD_VOLT_REG,
>> + DIMM_VRD1_VOLT_REG,
>> + DIMM_VRD2_VOLT_REG,
>> + /* vrd1 has higher priority than vrd2 using vrd1 as output for ddr */
>
> What is the point of this comment ?
>
>> + DIMM_VRD1_VOLT_REG,
>
> That doesn't make sense. It appears that DIMM VRD1
> is reported as DIMM VRD1 _and_ as DIMM VRD. I don't know
> what this is supposed to accomplish, but no. Please remove
> all instances of "virtual" attributes.
>
Yes, will try to remove "virtual" attr in next version.

>> + RCA_VRD_VOLT_REG,
>> +};
>> +
>> +static const u8 curr_regs[] = {
>> + CORE_VRD_CURR_REG,
>> + SOC_VRD_CURR_REG,
>> + DIMM_VRD1_CURR_REG,
>> + DIMM_VRD2_CURR_REG,
>> + RCA_VRD_CURR_REG,
>> +};
>> +
>> +enum pwr_regs {
>> + CORE_VRD_PWR,
>> + SOC_PWR,
>> + DIMM_VRD1_PWR,
>> + DIMM_VRD2_PWR,
>> + CPU_VRD_PWR,
>> + DIMM_VRD_PWR,
>> + RCA_VRD_PWR,
>> + SOC_TDP_PWR,
>> +};
>
> Add empty line. And run checkpatch - it would have told you.
>
Thanks, will fix this.

>> +static const char * const label[] = {
>> + "SoC",
>> + "SoC VRD",
>> + "DIMM VRD",
>> + "DIMM VRD1",
>> + "DIMM VRD2",
>> + "CORE VRD",
>> + "CH0 DIMM",
>> + "CH1 DIMM",
>> + "CH2 DIMM",
>> + "CH3 DIMM",
>> + "CH4 DIMM",
>> + "CH5 DIMM",
>> + "CH6 DIMM",
>> + "CH7 DIMM",
>> + "MEM HOT",
>> + "SoC VR HOT",
>> + "CPU VRD",
>> + "RCA VRD",
>> + "SOC TDP",
>> + "DIMM G0",
>> + "DIMM G1",
>> +};
>> +
>> +static int smpro_read_temp(struct device *dev, u32 attr, int channel,
>> + long *val)
>
> This looks suspicious, and indeed, checkpatch states:
>
> total: 0 errors, 2 warnings, 31 checks, 641 lines checked
>
> Besides, the line length limit is now 100 columns.
>
Thanks, let me check this.
>> +{
>> + struct smpro_hwmon *hwmon = dev_get_drvdata(dev);
>> + unsigned int t_max = 0xffffffff;
>> + unsigned int value;
>> + s32 i;
>> + int ret;
>> +
>> + switch (attr) {
>> + case hwmon_temp_input:
>> + if (temp_regs[channel] == DIMM_GROUP_DUMMY_REG) {
>> + for (i = 1; i <= 4; i++) {
>> + ret = regmap_read(hwmon->regmap,
>> + temp_regs[channel + i], &value);
>> + if (ret)
>> + return ret;
>> + /* continue if invalid */
>> + if (value == 0xffff)
>> + continue;
>> +
>> + value &= 0x1ff; /* 9-bit value */
>> + if (t_max != 0xffffffff)
>> + t_max = (value > t_max) ? value : t_max;
>> + else
>> + t_max = value;
>> + }
>
> This needs explanation. Why not return four different sensor values ?
> Otherwise, why four different registers to read data for a single sensor ?
>
> But ... no, wait, it looks like this is used to report the maximum
> of the subsequent four DIMMs. No, this is unacceptable. If this
> "channel" does not exist, but the index/channel is for some reason
> needed, report it as not visible using the is_visible callback.
>
>> +
>> + if (t_max == 0xffffffff)
>> + return -1;
>
> Valid error codes, please. -1 translates to -EPERM. However,
> it looks like this may suggest that the DIMMs are not populated.
> If so, mask affected channels using the is_visible callback.
>
Yes, you are right, this is to report the max temp among DIMMs.
We will drop it as it is "virtual" attr.
>> +
>> + *val = t_max * 1000;
>> + } else {
>> + ret = regmap_read(hwmon->regmap,
>> + temp_regs[channel], &value);
>> + if (ret)
>> + return ret;
>> + *val = (value & 0x1ff) * 1000;
>
> Above code suggests that a value of 0xffff might be reported,
> which micht suggest an unpopulated sensor (eg an unpouplated DIMM).
> The driver should not blindly report 255 Dgrees C in that situation,
> but instead mark the sensor as invisible.
>
> The same applies to all other sensors.
>
Thanks,
The value of 0xffff indeed indicate that the sensor is not available and
should be marked as invisible attr.

>> + }
>> + break;
>> + default:
>> + return -EOPNOTSUPP;
>> + }
>> + 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, volt_regs[channel], &value);
>> + if (ret < 0)
>> + return ret;
>> + *val = value & 0x7fff; /* 15-bit value */
>
> Scale reported by the hardware is 1mV ? Justw wondering;
> a brief comment might make sense.
>
Will add comment to clarify this.

>> + 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, curr_regs[channel], &value);
>> + if (ret < 0)
>> + return ret;
>> + *val = value & 0x7fff; /* 15-bit value */
>> + 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 val2, val2_mw;
>> + unsigned int val, val_mw;
>> + int ret;
>> +
>> + switch (attr) {
>> + case hwmon_power_input:
>> + switch (channel) {
>> + case CORE_VRD_PWR:
>> + ret = regmap_read(hwmon->regmap,
>> + CORE_VRD_PWR_REG, &val);
>> + if (!ret)
>> + ret = regmap_read(hwmon->regmap,
>> + CORE_VRD_PWR_MW_REG, &val_mw);
>> + if (ret)
>> + return ret;
>
> Please handle errors directly.
>
> ret = regmap_read();
> if (ret)
> return ret;
> ret = regmap_read()
> if (ret)
> return ret;
>
> Same everywhere below.
>
Will change them

>> + break;
>> + case SOC_PWR:
>> + ret = regmap_read(hwmon->regmap,
>> + SOC_PWR_REG, &val);
>> + if (!ret)
>> + ret = regmap_read(hwmon->regmap,
>> + SOC_PWR_MW_REG, &val_mw);
>> + if (ret)
>> + return ret;
>> + break;
>> + case DIMM_VRD1_PWR:
>> + ret = regmap_read(hwmon->regmap,
>> + DIMM_VRD1_PWR_REG, &val);
>> + if (!ret)
>> + ret = regmap_read(hwmon->regmap,
>> + DIMM_VRD1_PWR_MW_REG, &val_mw);
>> + if (ret)
>> + return ret;
>> + break;
>> + case DIMM_VRD2_PWR:
>> + ret = regmap_read(hwmon->regmap,
>> + DIMM_VRD2_PWR_REG, &val);
>> + if (!ret)
>> + ret = regmap_read(hwmon->regmap,
>> + DIMM_VRD2_PWR_MW_REG, &val_mw);
>> + if (ret)
>> + return ret;
>> + break;
>> + case RCA_VRD_PWR:
>> + ret = regmap_read(hwmon->regmap,
>> + RCA_VRD_PWR_REG, &val);
>> + if (!ret)
>> + ret = regmap_read(hwmon->regmap,
>> + RCA_VRD_PWR_MW_REG, &val_mw);
>> + if (ret)
>> + return ret;
>> + break;
>> + case SOC_TDP_PWR:
>> + ret = regmap_read(hwmon->regmap,
>> + SOC_TDP_REG, &val);
>> + if (ret)
>> + return ret;
>> + break;
>> + case CPU_VRD_PWR:
>> + ret = regmap_read(hwmon->regmap,
>> + CORE_VRD_PWR_REG, &val);
>> + if (!ret)
>> + ret = regmap_read(hwmon->regmap,
>> + CORE_VRD_PWR_MW_REG, &val_mw);
>> + if (!ret)
>> + ret = regmap_read(hwmon->regmap,
>> + SOC_PWR_REG, &val2);
>> + if (!ret)
>> + ret = regmap_read(hwmon->regmap,
>> + SOC_PWR_MW_REG, &val2_mw);
>> + if (ret)
>> + return ret;
>> + break;
>> + case DIMM_VRD_PWR:
>> + ret = regmap_read(hwmon->regmap,
>> + DIMM_VRD1_PWR_REG, &val);
>> + if (!ret)
>> + ret = regmap_read(hwmon->regmap,
>> + DIMM_VRD1_PWR_MW_REG, &val_mw);
>> + if (!ret)
>> + ret = regmap_read(hwmon->regmap,
>> + DIMM_VRD2_PWR_REG, &val2);
>> + if (!ret)
>> + ret = regmap_read(hwmon->regmap,
>> + DIMM_VRD2_PWR_MW_REG, &val2_mw);
>> + if (ret)
>> + return ret;
>> + break;
>
> Ah, there are more "virtual" atributes. Again, please remove all those.
> If userspace w ants to group attributes in whatever way it wants to, fine,
> but that is not a kernel concern.
>
> Besides, what if a DIMM is unpopulated ?
>
>> + default:
>> + return -EOPNOTSUPP;
>> + }
>> + /* Set to 0 if invalid */
>> + if (val_mw == 0xffff)
>> + val_mw = 0;
>> + if (val2_mw == 0xffff)
>> + val2_mw = 0;
>> +
>
> Does this indicate a temporary or a permanent problem ?
> If it means that the sensor is not populated, it should be
> handled in is_visible. Also, what about val / val2 ?
>
This means that the sensor is not populated and will be handled in
is_visible() in next version.

>> + *val_pwr = (val + val2) * 1000000 + (val_mw + val2_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_write(struct device *dev, enum hwmon_sensor_types type,
>> + u32 attr, int channel, long val)
>> +{
>> + return -EOPNOTSUPP;
>> +}
>> +
>> +static umode_t smpro_is_visible(const void *data,
>> + enum hwmon_sensor_types type,
>> + u32 attr, int channel)
>> +{
>> + return 0444;
>> +}
>> +
>> +static ssize_t show_label(struct device *dev, struct device_attribute *devattr,
>> + char *buf)
>> +{
>> + int index = to_sensor_dev_attr(devattr)->index;
>> +
>> + return sprintf(buf, "%s\n", label[index]);
>> +}
>> +
>> +static const u32 smpro_temp_config[] = {
>> + HWMON_T_INPUT,
>> + HWMON_T_INPUT,
>> + HWMON_T_INPUT,
>> + HWMON_T_INPUT,
>> + HWMON_T_INPUT,
>> + HWMON_T_INPUT,
>> + HWMON_T_INPUT,
>> + HWMON_T_INPUT,
>> + HWMON_T_INPUT,
>> + HWMON_T_INPUT,
>> + HWMON_T_INPUT,
>> + HWMON_T_INPUT,
>> + HWMON_T_INPUT,
>> + HWMON_T_INPUT,
>> + HWMON_T_INPUT,
>> + HWMON_T_INPUT,
>> + HWMON_T_INPUT,
>> + 0
>> +};
>> +
>> +static const struct hwmon_channel_info smpro_temp = {
>> + .type = hwmon_temp,
>> + .config = smpro_temp_config,
>> +};
>> +
>> +static const u32 smpro_in_config[] = {
>> + HWMON_I_INPUT,
>> + HWMON_I_INPUT,
>> + HWMON_I_INPUT,
>> + HWMON_I_INPUT,
>> + HWMON_I_INPUT,
>> + HWMON_I_INPUT,
>> + 0
>> +};
>> +
>> +static const struct hwmon_channel_info smpro_in = {
>> + .type = hwmon_in,
>> + .config = smpro_in_config,
>> +};
>> +
>> +static const u32 smpro_curr_config[] = {
>> + HWMON_C_INPUT,
>> + HWMON_C_INPUT,
>> + HWMON_C_INPUT,
>> + HWMON_C_INPUT,
>> + HWMON_C_INPUT,
>> + 0
>> +};
>> +
>> +static const struct hwmon_channel_info smpro_curr = {
>> + .type = hwmon_curr,
>> + .config = smpro_curr_config,
>> +};
>> +
>> +static const u32 smpro_power_config[] = {
>> + HWMON_P_INPUT,
>> + HWMON_P_INPUT,
>> + HWMON_P_INPUT,
>> + HWMON_P_INPUT,
>> + HWMON_P_INPUT,
>> + HWMON_P_INPUT,
>> + HWMON_P_INPUT,
>> + HWMON_P_INPUT,
>> + 0
>> +};
>> +
>> +static const struct hwmon_channel_info smpro_power = {
>> + .type = hwmon_power,
>> + .config = smpro_power_config,
>> +};
>> +
>> +static const struct hwmon_channel_info *smpro_info[] = {
>> + &smpro_temp,
>> + &smpro_in,
>> + &smpro_power,
>> + &smpro_curr,
>> + NULL
>> +};
>> +
>
> The above can all be polulated with HWMON_CHANNEL_INFO().
>
Will try this in next version.

>> +static const struct hwmon_ops smpro_hwmon_ops = {
>> + .is_visible = smpro_is_visible,
>> + .read = smpro_read,
>> + .write = smpro_write,
>> +};
>> +
>> +static const struct hwmon_chip_info smpro_chip_info = {
>> + .ops = &smpro_hwmon_ops,
>> + .info = smpro_info,
>> +};
>> +
>> +static SENSOR_DEVICE_ATTR(temp1_label, 0444, show_label, NULL, 0);
>> +static SENSOR_DEVICE_ATTR(temp2_label, 0444, show_label, NULL, 1);
>> +static SENSOR_DEVICE_ATTR(temp3_label, 0444, show_label, NULL, 2);
>> +static SENSOR_DEVICE_ATTR(temp4_label, 0444, show_label, NULL, 5);
>> +static SENSOR_DEVICE_ATTR(temp5_label, 0444, show_label, NULL, 19);
>> +static SENSOR_DEVICE_ATTR(temp6_label, 0444, show_label, NULL, 6);
>> +static SENSOR_DEVICE_ATTR(temp7_label, 0444, show_label, NULL, 7);
>> +static SENSOR_DEVICE_ATTR(temp8_label, 0444, show_label, NULL, 8);
>> +static SENSOR_DEVICE_ATTR(temp9_label, 0444, show_label, NULL, 9);
>> +static SENSOR_DEVICE_ATTR(temp10_label, 0444, show_label, NULL, 20);
>> +static SENSOR_DEVICE_ATTR(temp11_label, 0444, show_label, NULL, 10);
>> +static SENSOR_DEVICE_ATTR(temp12_label, 0444, show_label, NULL, 11);
>> +static SENSOR_DEVICE_ATTR(temp13_label, 0444, show_label, NULL, 12);
>> +static SENSOR_DEVICE_ATTR(temp14_label, 0444, show_label, NULL, 13);
>> +static SENSOR_DEVICE_ATTR(temp15_label, 0444, show_label, NULL, 14);
>> +static SENSOR_DEVICE_ATTR(temp16_label, 0444, show_label, NULL, 15);
>> +static SENSOR_DEVICE_ATTR(temp17_label, 0444, show_label, NULL, 17);
>> +
>> +static SENSOR_DEVICE_ATTR(in0_label, 0444, show_label, NULL, 5);
>> +static SENSOR_DEVICE_ATTR(in1_label, 0444, show_label, NULL, 1);
>> +static SENSOR_DEVICE_ATTR(in2_label, 0444, show_label, NULL, 3);
>> +static SENSOR_DEVICE_ATTR(in3_label, 0444, show_label, NULL, 4);
>> +static SENSOR_DEVICE_ATTR(in4_label, 0444, show_label, NULL, 2);
>> +static SENSOR_DEVICE_ATTR(in5_label, 0444, show_label, NULL, 17);
>> +
>> +static SENSOR_DEVICE_ATTR(power1_label, 0444, show_label, NULL, 5);
>> +static SENSOR_DEVICE_ATTR(power2_label, 0444, show_label, NULL, 0);
>> +static SENSOR_DEVICE_ATTR(power3_label, 0444, show_label, NULL, 3);
>> +static SENSOR_DEVICE_ATTR(power4_label, 0444, show_label, NULL, 4);
>> +static SENSOR_DEVICE_ATTR(power5_label, 0444, show_label, NULL, 16);
>> +static SENSOR_DEVICE_ATTR(power6_label, 0444, show_label, NULL, 2);
>> +static SENSOR_DEVICE_ATTR(power7_label, 0444, show_label, NULL, 17);
>> +static SENSOR_DEVICE_ATTR(power8_label, 0444, show_label, NULL, 18);
>> +
>> +static SENSOR_DEVICE_ATTR(curr1_label, 0444, show_label, NULL, 5);
>> +static SENSOR_DEVICE_ATTR(curr2_label, 0444, show_label, NULL, 1);
>> +static SENSOR_DEVICE_ATTR(curr3_label, 0444, show_label, NULL, 3);
>> +static SENSOR_DEVICE_ATTR(curr4_label, 0444, show_label, NULL, 4);
>> +static SENSOR_DEVICE_ATTR(curr5_label, 0444, show_label, NULL, 17);
>> +
>> +static struct attribute *smpro_attrs[] = {
>> + &sensor_dev_attr_temp1_label.dev_attr.attr,
>> + &sensor_dev_attr_temp2_label.dev_attr.attr,
>> + &sensor_dev_attr_temp3_label.dev_attr.attr,
>> + &sensor_dev_attr_temp4_label.dev_attr.attr,
>> + &sensor_dev_attr_temp5_label.dev_attr.attr,
>> + &sensor_dev_attr_temp6_label.dev_attr.attr,
>> + &sensor_dev_attr_temp7_label.dev_attr.attr,
>> + &sensor_dev_attr_temp8_label.dev_attr.attr,
>> + &sensor_dev_attr_temp9_label.dev_attr.attr,
>> + &sensor_dev_attr_temp10_label.dev_attr.attr,
>> + &sensor_dev_attr_temp11_label.dev_attr.attr,
>> + &sensor_dev_attr_temp12_label.dev_attr.attr,
>> + &sensor_dev_attr_temp13_label.dev_attr.attr,
>> + &sensor_dev_attr_temp14_label.dev_attr.attr,
>> + &sensor_dev_attr_temp15_label.dev_attr.attr,
>> + &sensor_dev_attr_temp16_label.dev_attr.attr,
>> + &sensor_dev_attr_temp17_label.dev_attr.attr,
>> +
>> + &sensor_dev_attr_in0_label.dev_attr.attr,
>> + &sensor_dev_attr_in1_label.dev_attr.attr,
>> + &sensor_dev_attr_in2_label.dev_attr.attr,
>> + &sensor_dev_attr_in3_label.dev_attr.attr,
>> + &sensor_dev_attr_in4_label.dev_attr.attr,
>> + &sensor_dev_attr_in5_label.dev_attr.attr,
>> +
>> + &sensor_dev_attr_curr1_label.dev_attr.attr,
>> + &sensor_dev_attr_curr2_label.dev_attr.attr,
>> + &sensor_dev_attr_curr3_label.dev_attr.attr,
>> + &sensor_dev_attr_curr4_label.dev_attr.attr,
>> + &sensor_dev_attr_curr5_label.dev_attr.attr,
>> +
>> + &sensor_dev_attr_power1_label.dev_attr.attr,
>> + &sensor_dev_attr_power2_label.dev_attr.attr,
>> + &sensor_dev_attr_power3_label.dev_attr.attr,
>> + &sensor_dev_attr_power4_label.dev_attr.attr,
>> + &sensor_dev_attr_power5_label.dev_attr.attr,
>> + &sensor_dev_attr_power6_label.dev_attr.attr,
>> + &sensor_dev_attr_power7_label.dev_attr.attr,
>> + &sensor_dev_attr_power8_label.dev_attr.attr,
>> +
>> + NULL
>> +};
>> +ATTRIBUTE_GROUPS(smpro);
>> +
>
> This can be done with LABEL attributes (HWMON_T_LABEL etc).
>
Thanks, will try this next time.

>> +static int is_valid_id(struct regmap *regmap)
>
> bool
>
>> +{
>> + unsigned int val;
>> + int ret;
>> +
>> + ret = regmap_read(regmap, MANUFACTURER_ID_REG, &val);
>> +
>> + return (ret || (val != AMPERE_MANUFACTURER_ID)) ? 0 : 1;
>> +}
>> +
>> +static int smpro_hwmon_probe(struct platform_device *pdev)
>> +{
>> + struct smpro_hwmon *hwmon;
>> + struct device *hwmon_dev;
>> +
>> + 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;
>> +
>> + /* Check for valid ID */
>> + if (!is_valid_id(hwmon->regmap))
>> + dev_warn(&pdev->dev, "Hmmh, SMPro not ready yet\n");
>
> This does not appear appropriate. It should be either -EPROBE_DEFER
> or -ENODEV.
>

Will re-check

>> +
>> + hwmon_dev = devm_hwmon_device_register_with_info(&pdev->dev,
>> + "smpro_hwmon", hwmon,
>> + &smpro_chip_info, smpro_groups);
>> + if (IS_ERR(hwmon_dev))
>> + dev_err(&pdev->dev, "failed to register as hwmon device");
>
> Unnecessary error message. It is either -EINVAL, which would
> always be the case, or -ENOMEM, which is already reported.
>
Will drop this message in next version.

>> +
>> + 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");
>>
>