Re: [PATCH v1 6/9] hwmon: Add Nuvoton NCT6694 HWMON support
From: Ming Yu <hidden>
Date: 2024-10-25 15:10:51
Also in:
linux-can, linux-gpio, linux-hwmon, linux-i2c, linux-iio, linux-pwm, linux-rtc, linux-watchdog, lkml
Dear Kalesh, Thank you for your comments. Ming Kalesh Anakkur Purayil [off-list ref] 於 2024年10月24日 週四 下午5:20寫道：
On Thu, Oct 24, 2024 at 2:33 PM Ming Yu [off-list ref] wrote:quoted
This driver supports Hardware monitor functionality for NCT6694 MFD device based on USB interface. Signed-off-by: Ming Yu <tmyu0@nuvoton.com> --- MAINTAINERS | 1 + drivers/hwmon/Kconfig | 10 + drivers/hwmon/Makefile | 1 + drivers/hwmon/nct6694-hwmon.c | 407 ++++++++++++++++++++++++++++++++++ 4 files changed, 419 insertions(+) create mode 100644 drivers/hwmon/nct6694-hwmon.cdiff --git a/MAINTAINERS b/MAINTAINERS index 63387c0d4ab6..2aa87ad84156 100644 --- a/MAINTAINERS +++ b/MAINTAINERS@@ -16439,6 +16439,7 @@ M: Ming Yu <tmyu0@nuvoton.com> L: linux-kernel@vger.kernel.org S: Supported F: drivers/gpio/gpio-nct6694.c +F: drivers/hwmon/nct6694-hwmon.c F: drivers/i2c/busses/i2c-nct6694.c F: drivers/mfd/nct6694.c F: drivers/net/can/nct6694_canfd.cdiff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig index 08a3c863f80a..740e4afe6582 100644 --- a/drivers/hwmon/Kconfig +++ b/drivers/hwmon/Kconfig@@ -1625,6 +1625,16 @@ config SENSORS_NCT6683 This driver can also be built as a module. If so, the module will be called nct6683. +config SENSORS_NCT6694 + tristate "Nuvoton NCT6694 Hardware Monitor support" + depends on MFD_NCT6694 + help + Say Y here to support Nuvoton NCT6694 hardware monitoring + functionality. + + This driver can also be built as a module. If so, the module + will be called nct6694-hwmon. + config SENSORS_NCT6775_CORE tristate select REGMAPdiff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile index 9554d2fdcf7b..729961176d00 100644 --- a/drivers/hwmon/Makefile +++ b/drivers/hwmon/Makefile@@ -167,6 +167,7 @@ obj-$(CONFIG_SENSORS_MLXREG_FAN) += mlxreg-fan.o obj-$(CONFIG_SENSORS_MENF21BMC_HWMON) += menf21bmc_hwmon.o obj-$(CONFIG_SENSORS_MR75203) += mr75203.o obj-$(CONFIG_SENSORS_NCT6683) += nct6683.o +obj-$(CONFIG_SENSORS_NCT6694) += nct6694-hwmon.o obj-$(CONFIG_SENSORS_NCT6775_CORE) += nct6775-core.o nct6775-objs := nct6775-platform.o obj-$(CONFIG_SENSORS_NCT6775) += nct6775.odiff --git a/drivers/hwmon/nct6694-hwmon.c b/drivers/hwmon/nct6694-hwmon.c new file mode 100644 index 000000000000..7d7d22a650b0 --- /dev/null +++ b/drivers/hwmon/nct6694-hwmon.c@@ -0,0 +1,407 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Nuvoton NCT6694 HWMON driver based on USB interface. + * + * Copyright (C) 2024 Nuvoton Technology Corp. + */ + +#include <linux/slab.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/hwmon.h> +#include <linux/platform_device.h> +#include <linux/mfd/nct6694.h> + +#define DRVNAME "nct6694-hwmon" + +/* Host interface */ +#define REQUEST_RPT_MOD 0xFF +#define REQUEST_HWMON_MOD 0x00 + +/* Report Channel */ +#define HWMON_FIN_IDX(x) (0x50 + ((x) * 2)) +#define HWMON_FIN_STS(x) (0x6E + (x)) +#define HWMON_PWM_IDX(x) (0x70 + (x)) + +/* Message Channel*/ +/* Command 00h */ +#define REQUEST_HWMON_CMD0_LEN 0x40 +#define REQUEST_HWMON_CMD0_OFFSET 0x0000 /* OFFSET = SEL|CMD */ +#define HWMON_FIN_EN(x) (0x04 + (x)) +#define HWMON_PWM_FREQ_IDX(x) (0x30 + (x)) +/* Command 02h */ +#define REQUEST_HWMON_CMD2_LEN 0x90 +#define REQUEST_HWMON_CMD2_OFFSET 0x0002 /* OFFSET = SEL|CMD */ +#define HWMON_SMI_CTRL_IDX 0x00 +#define HWMON_FIN_LIMIT_IDX(x) (0x70 + ((x) * 2)) +#define HWMON_CMD2_HYST_MASK 0x1F +/* Command 03h */ +#define REQUEST_HWMON_CMD3_LEN 0x08 +#define REQUEST_HWMON_CMD3_OFFSET 0x0003 /* OFFSET = SEL|CMD */ + +struct nct6694_hwmon_data { + struct nct6694 *nct6694; + + /* Make sure read & write commands are consecutive */ + struct mutex hwmon_lock; +}; + +#define NCT6694_HWMON_FAN_CONFIG (HWMON_F_ENABLE | HWMON_F_INPUT | \ + HWMON_F_MIN | HWMON_F_MIN_ALARM) +#define NCT6694_HWMON_PWM_CONFIG (HWMON_PWM_INPUT | HWMON_PWM_FREQ) + +static const struct hwmon_channel_info *nct6694_info[] = { + HWMON_CHANNEL_INFO(fan, + NCT6694_HWMON_FAN_CONFIG, /* FIN0 */ + NCT6694_HWMON_FAN_CONFIG, /* FIN1 */ + NCT6694_HWMON_FAN_CONFIG, /* FIN2 */ + NCT6694_HWMON_FAN_CONFIG, /* FIN3 */ + NCT6694_HWMON_FAN_CONFIG, /* FIN4 */ + NCT6694_HWMON_FAN_CONFIG, /* FIN5 */ + NCT6694_HWMON_FAN_CONFIG, /* FIN6 */ + NCT6694_HWMON_FAN_CONFIG, /* FIN7 */ + NCT6694_HWMON_FAN_CONFIG, /* FIN8 */ + NCT6694_HWMON_FAN_CONFIG), /* FIN9 */ + + HWMON_CHANNEL_INFO(pwm, + NCT6694_HWMON_PWM_CONFIG, /* PWM0 */ + NCT6694_HWMON_PWM_CONFIG, /* PWM1 */ + NCT6694_HWMON_PWM_CONFIG, /* PWM2 */ + NCT6694_HWMON_PWM_CONFIG, /* PWM3 */ + NCT6694_HWMON_PWM_CONFIG, /* PWM4 */ + NCT6694_HWMON_PWM_CONFIG, /* PWM5 */ + NCT6694_HWMON_PWM_CONFIG, /* PWM6 */ + NCT6694_HWMON_PWM_CONFIG, /* PWM7 */ + NCT6694_HWMON_PWM_CONFIG, /* PWM8 */ + NCT6694_HWMON_PWM_CONFIG), /* PWM9 */ + NULL +}; + +static int nct6694_fan_read(struct device *dev, u32 attr, int channel, + long *val) +{ + struct nct6694_hwmon_data *data = dev_get_drvdata(dev); + unsigned char buf[2]; + int ret; + + switch (attr) { + case hwmon_fan_enable: + ret = nct6694_read_msg(data->nct6694, REQUEST_HWMON_MOD, + REQUEST_HWMON_CMD0_OFFSET, + REQUEST_HWMON_CMD0_LEN, + HWMON_FIN_EN(channel / 8), + 1, buf); + if (ret) + return -EINVAL; + + *val = buf[0] & BIT(channel % 8) ? 1 : 0; + + break; + + case hwmon_fan_input: + ret = nct6694_read_msg(data->nct6694, REQUEST_RPT_MOD, + HWMON_FIN_IDX(channel), 2, 0, + 2, buf); + if (ret) + return -EINVAL; + + *val = (buf[1] | (buf[0] << 8)) & 0xFFFF; + + break; + + case hwmon_fan_min: + ret = nct6694_read_msg(data->nct6694, REQUEST_HWMON_MOD, + REQUEST_HWMON_CMD2_OFFSET, + REQUEST_HWMON_CMD2_LEN, + HWMON_FIN_LIMIT_IDX(channel), + 2, buf); + if (ret) + return -EINVAL; + + *val = (buf[1] | (buf[0] << 8)) & 0xFFFF; + + break; + + case hwmon_fan_min_alarm: + ret = nct6694_read_msg(data->nct6694, REQUEST_RPT_MOD, + HWMON_FIN_STS(channel / 8), + 1, 0, 1, buf); + if (ret) + return -EINVAL; + + *val = buf[0] & BIT(channel % 8); + + break; + + default: + return -EOPNOTSUPP; + } + + return 0; +} + +static int nct6694_pwm_read(struct device *dev, u32 attr, int channel, + long *val) +{ + struct nct6694_hwmon_data *data = dev_get_drvdata(dev); + unsigned char buf; + int ret; + + switch (attr) { + case hwmon_pwm_input: + ret = nct6694_read_msg(data->nct6694, REQUEST_RPT_MOD, + HWMON_PWM_IDX(channel), + 1, 0, 1, &buf); + if (ret) + return -EINVAL; + + *val = buf; + + break; + case hwmon_pwm_freq: + ret = nct6694_read_msg(data->nct6694, REQUEST_HWMON_MOD, + REQUEST_HWMON_CMD0_OFFSET, + REQUEST_HWMON_CMD0_LEN, + HWMON_PWM_FREQ_IDX(channel), + 1, &buf); + if (ret) + return -EINVAL; + + *val = buf * 25000 / 255; + + break; + + default: + return -EOPNOTSUPP; + } + + return 0; +} + +static int nct6694_fan_write(struct device *dev, u32 attr, int channel, + long val) +{ + struct nct6694_hwmon_data *data = dev_get_drvdata(dev); + unsigned char enable_buf[REQUEST_HWMON_CMD0_LEN] = {0};[Kalesh] Please try to maintain RCT order for variable declarationquoted
+ unsigned char buf[REQUEST_HWMON_CMD2_LEN] = {0}; + u16 fan_val = (u16)val; + int ret; + + switch (attr) { + case hwmon_fan_enable: + mutex_lock(&data->hwmon_lock); + ret = nct6694_read_msg(data->nct6694, REQUEST_HWMON_MOD, + REQUEST_HWMON_CMD0_OFFSET, + REQUEST_HWMON_CMD0_LEN, 0, + REQUEST_HWMON_CMD0_LEN, + enable_buf); + if (ret) + goto err; + + if (val) + enable_buf[HWMON_FIN_EN(channel / 8)] |= BIT(channel % 8); + else + enable_buf[HWMON_FIN_EN(channel / 8)] &= ~BIT(channel % 8); + + ret = nct6694_write_msg(data->nct6694, REQUEST_HWMON_MOD, + REQUEST_HWMON_CMD0_OFFSET, + REQUEST_HWMON_CMD0_LEN, enable_buf); + if (ret) + goto err; + + break; + + case hwmon_fan_min: + mutex_lock(&data->hwmon_lock); + ret = nct6694_read_msg(data->nct6694, REQUEST_HWMON_MOD, + REQUEST_HWMON_CMD2_OFFSET, + REQUEST_HWMON_CMD2_LEN, 0, + REQUEST_HWMON_CMD2_LEN, buf); + if (ret) + goto err; + + buf[HWMON_FIN_LIMIT_IDX(channel)] = (u8)((fan_val >> 8) & 0xFF); + buf[HWMON_FIN_LIMIT_IDX(channel) + 1] = (u8)(fan_val & 0xFF); + ret = nct6694_write_msg(data->nct6694, REQUEST_HWMON_MOD, + REQUEST_HWMON_CMD2_OFFSET, + REQUEST_HWMON_CMD2_LEN, buf); + if (ret) + goto err; + + break; + + default: + ret = -EOPNOTSUPP;[Kalesh] If you initialize "ret = -EOPNOTSUPP;" during declararion, you can just break from here.quoted
+ goto err; + } + +err: + mutex_unlock(&data->hwmon_lock); + return ret; +} + +static int nct6694_read(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int channel, long *val) +{ + switch (type) { + case hwmon_fan: /* in RPM */ + return nct6694_fan_read(dev, attr, channel, val); + + case hwmon_pwm: /* in value 0~255 */ + return nct6694_pwm_read(dev, attr, channel, val); + + default: + return -EOPNOTSUPP; + } + + return 0; +} + +static int nct6694_write(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int channel, long val) +{ + switch (type) { + case hwmon_fan: + return nct6694_fan_write(dev, attr, channel, val); + default: + return -EOPNOTSUPP; + }[Kalesh] You can use simple if condition here than a switch like: if (type != hwmon_fan) return -EOPNOTSUPP; return nct6694_fan_write(dev, attr, channel, val);quoted
+ + return 0; +} + +static umode_t nct6694_is_visible(const void *data, enum hwmon_sensor_types type, + u32 attr, int channel) +{ + switch (type) { + case hwmon_fan: + switch (attr) { + case hwmon_fan_enable: + case hwmon_fan_min: + return 0644;[Kalesh] I think there is no need to leave a new line in between casesquoted
+ + case hwmon_fan_input: + case hwmon_fan_min_alarm: + return 0444; + + default: + return 0; + } + + case hwmon_pwm: + switch (attr) { + case hwmon_pwm_input: + case hwmon_pwm_freq: + return 0444; + default: + return 0; + } + + default: + return 0; + } + + return 0;[Kalesh] This return statement looks redundant as the execution never reaches here. Same comment applies to other functions above as well.quoted
+} + +static const struct hwmon_ops nct6694_hwmon_ops = { + .is_visible = nct6694_is_visible, + .read = nct6694_read, + .write = nct6694_write, +}; + +static const struct hwmon_chip_info nct6694_chip_info = { + .ops = &nct6694_hwmon_ops, + .info = nct6694_info, +}; + +static int nct6694_hwmon_init(struct nct6694_hwmon_data *data) +{ + unsigned char buf[REQUEST_HWMON_CMD2_LEN] = {0}; + int ret; + + /* Set Fan input Real Time alarm mode */ + mutex_lock(&data->hwmon_lock); + ret = nct6694_read_msg(data->nct6694, REQUEST_HWMON_MOD, + REQUEST_HWMON_CMD2_OFFSET, + REQUEST_HWMON_CMD2_LEN, 0, + REQUEST_HWMON_CMD2_LEN, buf); + if (ret) + goto err;[Kalesh] It would be better to rename the label as "unlock". Same comment on other functions as well.quoted
+ + buf[HWMON_SMI_CTRL_IDX] = 0x02; + + ret = nct6694_write_msg(data->nct6694, REQUEST_HWMON_MOD, + REQUEST_HWMON_CMD2_OFFSET, + REQUEST_HWMON_CMD2_LEN, buf); + if (ret) + goto err; + +err: + mutex_unlock(&data->hwmon_lock); + return ret; +} + +static int nct6694_hwmon_probe(struct platform_device *pdev) +{ + struct nct6694_hwmon_data *data; + struct nct6694 *nct6694 = dev_get_drvdata(pdev->dev.parent); + struct device *hwmon_dev; + int ret; + + data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->nct6694 = nct6694; + mutex_init(&data->hwmon_lock); + platform_set_drvdata(pdev, data); + + ret = nct6694_hwmon_init(data); + if (ret) + return -EIO; + + /* Register hwmon device to HWMON framework */ + hwmon_dev = devm_hwmon_device_register_with_info(&pdev->dev, + "nct6694", data, + &nct6694_chip_info, + NULL); + if (IS_ERR(hwmon_dev)) { + dev_err(&pdev->dev, "%s: Failed to register hwmon device!\n", + __func__); + return PTR_ERR(hwmon_dev); + } + + return 0; +} + +static struct platform_driver nct6694_hwmon_driver = { + .driver = { + .name = DRVNAME, + }, + .probe = nct6694_hwmon_probe, +}; + +static int __init nct6694_init(void) +{ + int err; + + err = platform_driver_register(&nct6694_hwmon_driver); + if (!err) { + if (err)[Kalesh] This whole check looks strange. You can simplify this function as: return platform_driver_register(&nct6694_hwmon_driver);quoted
+ platform_driver_unregister(&nct6694_hwmon_driver); + } + + return err; +} +subsys_initcall(nct6694_init); + +static void __exit nct6694_exit(void) +{ + platform_driver_unregister(&nct6694_hwmon_driver); +} +module_exit(nct6694_exit); + +MODULE_DESCRIPTION("USB-HWMON driver for NCT6694"); +MODULE_AUTHOR("Ming Yu [off-list ref]"); +MODULE_LICENSE("GPL"); -- 2.34.1-- Regards, Kalesh A P