]> git.ipfire.org Git - thirdparty/kernel/stable.git/commitdiff
hwmon: Add Nuvoton NCT6694 HWMON support
authorMing Yu <a0282524688@gmail.com>
Fri, 12 Sep 2025 09:19:51 +0000 (17:19 +0800)
committerLee Jones <lee@kernel.org>
Tue, 16 Sep 2025 13:41:57 +0000 (14:41 +0100)
This driver supports Hardware monitor functionality for NCT6694 MFD
device based on USB interface.

Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Ming Yu <a0282524688@gmail.com>
Link: https://lore.kernel.org/r/20250912091952.1169369-7-a0282524688@gmail.com
Signed-off-by: Lee Jones <lee@kernel.org>
MAINTAINERS
drivers/hwmon/Kconfig
drivers/hwmon/Makefile
drivers/hwmon/nct6694-hwmon.c [new file with mode: 0644]

index 4639d5933c5ec73581bba7fbc04a91f582a7f120..bbacc9d48a8331bfa80b6384f48cb2eae04d69cd 100644 (file)
@@ -18086,6 +18086,7 @@ NUVOTON NCT6694 MFD DRIVER
 M:     Ming Yu <tmyu0@nuvoton.com>
 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/usb/nct6694_canfd.c
index 9d28fcf7cd2a6f9e2f54694a717bd85ff4047b46..19f660d9a0c54018b0a5340af8382ce9cc6a2319 100644 (file)
@@ -1698,6 +1698,16 @@ 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 REGMAP
index cd8bc4752b4dbf015c6eb46157626f4e8f87dfae..9bce91611dc379fc110361734481693b9d3d5860 100644 (file)
@@ -174,6 +174,7 @@ 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.o
diff --git a/drivers/hwmon/nct6694-hwmon.c b/drivers/hwmon/nct6694-hwmon.c
new file mode 100644 (file)
index 0000000..6dcf22c
--- /dev/null
@@ -0,0 +1,949 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Nuvoton NCT6694 HWMON driver based on USB interface.
+ *
+ * Copyright (C) 2025 Nuvoton Technology Corp.
+ */
+
+#include <linux/bits.h>
+#include <linux/bitfield.h>
+#include <linux/hwmon.h>
+#include <linux/kernel.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/nct6694.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+/*
+ * USB command module type for NCT6694 report channel
+ * This defines the module type used for communication with the NCT6694
+ * report channel over the USB interface.
+ */
+#define NCT6694_RPT_MOD                        0xFF
+
+/* Report channel */
+/*
+ * The report channel is used to report the status of the hardware monitor
+ * devices, such as voltage, temperature, fan speed, and PWM.
+ */
+#define NCT6694_VIN_IDX(x)             (0x00 + (x))
+#define NCT6694_TIN_IDX(x)                     \
+       ({ typeof(x) (_x) = (x);                \
+        ((_x) < 10) ? (0x10 + ((_x) * 2)) :    \
+        (0x30 + (((_x) - 10) * 2)); })
+#define NCT6694_FIN_IDX(x)             (0x50 + ((x) * 2))
+#define NCT6694_PWM_IDX(x)             (0x70 + (x))
+#define NCT6694_VIN_STS(x)             (0x68 + (x))
+#define NCT6694_TIN_STS(x)             (0x6A + (x))
+#define NCT6694_FIN_STS(x)             (0x6E + (x))
+
+/*
+ * USB command module type for NCT6694 HWMON controller.
+ * This defines the module type used for communication with the NCT6694
+ * HWMON controller over the USB interface.
+ */
+#define NCT6694_HWMON_MOD              0x00
+
+/* Command 00h - Hardware Monitor Control */
+#define NCT6694_HWMON_CONTROL          0x00
+#define NCT6694_HWMON_CONTROL_SEL      0x00
+
+/* Command 02h - Alarm Control */
+#define NCT6694_HWMON_ALARM            0x02
+#define NCT6694_HWMON_ALARM_SEL                0x00
+
+/*
+ * USB command module type for NCT6694 PWM controller.
+ * This defines the module type used for communication with the NCT6694
+ * PWM controller over the USB interface.
+ */
+#define NCT6694_PWM_MOD                        0x01
+
+/* PWM Command - Manual Control */
+#define NCT6694_PWM_CONTROL            0x01
+#define NCT6694_PWM_CONTROL_SEL                0x00
+
+#define NCT6694_FREQ_FROM_REG(reg)     ((reg) * 25000 / 255)
+#define NCT6694_FREQ_TO_REG(val)       \
+       (DIV_ROUND_CLOSEST(clamp_val((val), 100, 25000) * 255, 25000))
+
+#define NCT6694_LSB_REG_MASK           GENMASK(7, 5)
+#define NCT6694_TIN_HYST_MASK          GENMASK(7, 5)
+
+enum nct6694_hwmon_temp_mode {
+       NCT6694_HWMON_TWOTIME_IRQ = 0,
+       NCT6694_HWMON_ONETIME_IRQ,
+       NCT6694_HWMON_REALTIME_IRQ,
+       NCT6694_HWMON_COMPARE_IRQ,
+};
+
+struct __packed nct6694_hwmon_control {
+       u8 vin_en[2];
+       u8 tin_en[2];
+       u8 fin_en[2];
+       u8 pwm_en[2];
+       u8 reserved1[40];
+       u8 pwm_freq[10];
+       u8 reserved2[6];
+};
+
+struct __packed nct6694_hwmon_alarm {
+       u8 smi_ctrl;
+       u8 reserved1[15];
+       struct {
+               u8 hl;
+               u8 ll;
+       } vin_limit[16];
+       struct {
+               u8 hyst;
+               s8 hl;
+       } tin_cfg[32];
+       __be16 fin_ll[10];
+       u8 reserved2[4];
+};
+
+struct __packed nct6694_pwm_control {
+       u8 mal_en[2];
+       u8 mal_val[10];
+       u8 reserved[12];
+};
+
+union __packed nct6694_hwmon_rpt {
+       u8 vin;
+       struct {
+               u8 msb;
+               u8 lsb;
+       } tin;
+       __be16 fin;
+       u8 pwm;
+       u8 status;
+};
+
+union __packed nct6694_hwmon_msg {
+       struct nct6694_hwmon_alarm hwmon_alarm;
+       struct nct6694_pwm_control pwm_ctrl;
+};
+
+struct nct6694_hwmon_data {
+       struct nct6694 *nct6694;
+       struct mutex lock;
+       struct nct6694_hwmon_control hwmon_en;
+       union nct6694_hwmon_rpt *rpt;
+       union nct6694_hwmon_msg *msg;
+};
+
+static inline long in_from_reg(u8 reg)
+{
+       return reg * 16;
+}
+
+static inline u8 in_to_reg(long val)
+{
+       return DIV_ROUND_CLOSEST(val, 16);
+}
+
+static inline long temp_from_reg(s8 reg)
+{
+       return reg * 1000;
+}
+
+static inline s8 temp_to_reg(long val)
+{
+       return DIV_ROUND_CLOSEST(val, 1000);
+}
+
+#define NCT6694_HWMON_IN_CONFIG (HWMON_I_INPUT | HWMON_I_ENABLE |      \
+                                HWMON_I_MAX | HWMON_I_MIN |            \
+                                HWMON_I_ALARM)
+#define NCT6694_HWMON_TEMP_CONFIG (HWMON_T_INPUT | HWMON_T_ENABLE |    \
+                                  HWMON_T_MAX | HWMON_T_MAX_HYST |     \
+                                  HWMON_T_MAX_ALARM)
+#define NCT6694_HWMON_FAN_CONFIG (HWMON_F_INPUT | HWMON_F_ENABLE |     \
+                                 HWMON_F_MIN | HWMON_F_MIN_ALARM)
+#define NCT6694_HWMON_PWM_CONFIG (HWMON_PWM_INPUT | HWMON_PWM_ENABLE | \
+                                 HWMON_PWM_FREQ)
+static const struct hwmon_channel_info *nct6694_info[] = {
+       HWMON_CHANNEL_INFO(in,
+                          NCT6694_HWMON_IN_CONFIG,     /* VIN0 */
+                          NCT6694_HWMON_IN_CONFIG,     /* VIN1 */
+                          NCT6694_HWMON_IN_CONFIG,     /* VIN2 */
+                          NCT6694_HWMON_IN_CONFIG,     /* VIN3 */
+                          NCT6694_HWMON_IN_CONFIG,     /* VIN5 */
+                          NCT6694_HWMON_IN_CONFIG,     /* VIN6 */
+                          NCT6694_HWMON_IN_CONFIG,     /* VIN7 */
+                          NCT6694_HWMON_IN_CONFIG,     /* VIN14 */
+                          NCT6694_HWMON_IN_CONFIG,     /* VIN15 */
+                          NCT6694_HWMON_IN_CONFIG,     /* VIN16 */
+                          NCT6694_HWMON_IN_CONFIG,     /* VBAT */
+                          NCT6694_HWMON_IN_CONFIG,     /* VSB */
+                          NCT6694_HWMON_IN_CONFIG,     /* AVSB */
+                          NCT6694_HWMON_IN_CONFIG,     /* VCC */
+                          NCT6694_HWMON_IN_CONFIG,     /* VHIF */
+                          NCT6694_HWMON_IN_CONFIG),    /* VTT */
+
+       HWMON_CHANNEL_INFO(temp,
+                          NCT6694_HWMON_TEMP_CONFIG,   /* THR1 */
+                          NCT6694_HWMON_TEMP_CONFIG,   /* THR2 */
+                          NCT6694_HWMON_TEMP_CONFIG,   /* THR14 */
+                          NCT6694_HWMON_TEMP_CONFIG,   /* THR15 */
+                          NCT6694_HWMON_TEMP_CONFIG,   /* THR16 */
+                          NCT6694_HWMON_TEMP_CONFIG,   /* TDP0 */
+                          NCT6694_HWMON_TEMP_CONFIG,   /* TDP1 */
+                          NCT6694_HWMON_TEMP_CONFIG,   /* TDP2 */
+                          NCT6694_HWMON_TEMP_CONFIG,   /* TDP3 */
+                          NCT6694_HWMON_TEMP_CONFIG,   /* TDP4 */
+                          NCT6694_HWMON_TEMP_CONFIG,   /* DTIN0 */
+                          NCT6694_HWMON_TEMP_CONFIG,   /* DTIN1 */
+                          NCT6694_HWMON_TEMP_CONFIG,   /* DTIN2 */
+                          NCT6694_HWMON_TEMP_CONFIG,   /* DTIN3 */
+                          NCT6694_HWMON_TEMP_CONFIG,   /* DTIN4 */
+                          NCT6694_HWMON_TEMP_CONFIG,   /* DTIN5 */
+                          NCT6694_HWMON_TEMP_CONFIG,   /* DTIN6 */
+                          NCT6694_HWMON_TEMP_CONFIG,   /* DTIN7 */
+                          NCT6694_HWMON_TEMP_CONFIG,   /* DTIN8 */
+                          NCT6694_HWMON_TEMP_CONFIG,   /* DTIN9 */
+                          NCT6694_HWMON_TEMP_CONFIG,   /* DTIN10 */
+                          NCT6694_HWMON_TEMP_CONFIG,   /* DTIN11 */
+                          NCT6694_HWMON_TEMP_CONFIG,   /* DTIN12 */
+                          NCT6694_HWMON_TEMP_CONFIG,   /* DTIN13 */
+                          NCT6694_HWMON_TEMP_CONFIG,   /* DTIN14 */
+                          NCT6694_HWMON_TEMP_CONFIG),  /* DTIN15 */
+
+       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_in_read(struct device *dev, u32 attr, int channel,
+                          long *val)
+{
+       struct nct6694_hwmon_data *data = dev_get_drvdata(dev);
+       struct nct6694_cmd_header cmd_hd;
+       unsigned char vin_en;
+       int ret;
+
+       guard(mutex)(&data->lock);
+
+       switch (attr) {
+       case hwmon_in_enable:
+               vin_en = data->hwmon_en.vin_en[(channel / 8)];
+               *val = !!(vin_en & BIT(channel % 8));
+
+               return 0;
+       case hwmon_in_input:
+               cmd_hd = (struct nct6694_cmd_header) {
+                       .mod = NCT6694_RPT_MOD,
+                       .offset = cpu_to_le16(NCT6694_VIN_IDX(channel)),
+                       .len = cpu_to_le16(sizeof(data->rpt->vin))
+               };
+               ret = nct6694_read_msg(data->nct6694, &cmd_hd,
+                                      &data->rpt->vin);
+               if (ret)
+                       return ret;
+
+               *val = in_from_reg(data->rpt->vin);
+
+               return 0;
+       case hwmon_in_max:
+               cmd_hd = (struct nct6694_cmd_header) {
+                       .mod = NCT6694_HWMON_MOD,
+                       .cmd = NCT6694_HWMON_ALARM,
+                       .sel = NCT6694_HWMON_ALARM_SEL,
+                       .len = cpu_to_le16(sizeof(data->msg->hwmon_alarm))
+               };
+               ret = nct6694_read_msg(data->nct6694, &cmd_hd,
+                                      &data->msg->hwmon_alarm);
+               if (ret)
+                       return ret;
+
+               *val = in_from_reg(data->msg->hwmon_alarm.vin_limit[channel].hl);
+
+               return 0;
+       case hwmon_in_min:
+               cmd_hd = (struct nct6694_cmd_header) {
+                       .mod = NCT6694_HWMON_MOD,
+                       .cmd = NCT6694_HWMON_ALARM,
+                       .sel = NCT6694_HWMON_ALARM_SEL,
+                       .len = cpu_to_le16(sizeof(data->msg->hwmon_alarm))
+               };
+               ret = nct6694_read_msg(data->nct6694, &cmd_hd,
+                                      &data->msg->hwmon_alarm);
+               if (ret)
+                       return ret;
+
+               *val = in_from_reg(data->msg->hwmon_alarm.vin_limit[channel].ll);
+
+               return 0;
+       case hwmon_in_alarm:
+               cmd_hd = (struct nct6694_cmd_header) {
+                       .mod = NCT6694_RPT_MOD,
+                       .offset = cpu_to_le16(NCT6694_VIN_STS(channel / 8)),
+                       .len = cpu_to_le16(sizeof(data->rpt->status))
+               };
+               ret = nct6694_read_msg(data->nct6694, &cmd_hd,
+                                      &data->rpt->status);
+               if (ret)
+                       return ret;
+
+               *val = !!(data->rpt->status & BIT(channel % 8));
+
+               return 0;
+       default:
+               return -EOPNOTSUPP;
+       }
+}
+
+static int nct6694_temp_read(struct device *dev, u32 attr, int channel,
+                            long *val)
+{
+       struct nct6694_hwmon_data *data = dev_get_drvdata(dev);
+       struct nct6694_cmd_header cmd_hd;
+       unsigned char temp_en, temp_hyst;
+       signed char temp_max;
+       int ret, temp_raw;
+
+       guard(mutex)(&data->lock);
+
+       switch (attr) {
+       case hwmon_temp_enable:
+               temp_en = data->hwmon_en.tin_en[channel / 8];
+               *val = !!(temp_en & BIT(channel % 8));
+
+               return 0;
+       case hwmon_temp_input:
+               cmd_hd = (struct nct6694_cmd_header) {
+                       .mod = NCT6694_RPT_MOD,
+                       .offset = cpu_to_le16(NCT6694_TIN_IDX(channel)),
+                       .len = cpu_to_le16(sizeof(data->rpt->tin))
+               };
+               ret = nct6694_read_msg(data->nct6694, &cmd_hd,
+                                      &data->rpt->tin);
+               if (ret)
+                       return ret;
+
+               temp_raw = data->rpt->tin.msb << 3;
+               temp_raw |= FIELD_GET(NCT6694_LSB_REG_MASK, data->rpt->tin.lsb);
+
+               /* Real temperature(milli degrees Celsius) = temp_raw * 1000 * 0.125 */
+               *val = sign_extend32(temp_raw, 10) * 125;
+
+               return 0;
+       case hwmon_temp_max:
+               cmd_hd = (struct nct6694_cmd_header) {
+                       .mod = NCT6694_HWMON_MOD,
+                       .cmd = NCT6694_HWMON_ALARM,
+                       .sel = NCT6694_HWMON_ALARM_SEL,
+                       .len = cpu_to_le16(sizeof(data->msg->hwmon_alarm))
+               };
+               ret = nct6694_read_msg(data->nct6694, &cmd_hd,
+                                      &data->msg->hwmon_alarm);
+               if (ret)
+                       return ret;
+
+               *val = temp_from_reg(data->msg->hwmon_alarm.tin_cfg[channel].hl);
+
+               return 0;
+       case hwmon_temp_max_hyst:
+               cmd_hd = (struct nct6694_cmd_header) {
+                       .mod = NCT6694_HWMON_MOD,
+                       .cmd = NCT6694_HWMON_ALARM,
+                       .sel = NCT6694_HWMON_ALARM_SEL,
+                       .len = cpu_to_le16(sizeof(data->msg->hwmon_alarm))
+               };
+               ret = nct6694_read_msg(data->nct6694, &cmd_hd,
+                                      &data->msg->hwmon_alarm);
+               if (ret)
+                       return ret;
+
+               temp_max = data->msg->hwmon_alarm.tin_cfg[channel].hl;
+               temp_hyst = FIELD_GET(NCT6694_TIN_HYST_MASK,
+                                     data->msg->hwmon_alarm.tin_cfg[channel].hyst);
+               *val = temp_from_reg(temp_max - temp_hyst);
+
+               return 0;
+       case hwmon_temp_max_alarm:
+               cmd_hd = (struct nct6694_cmd_header) {
+                       .mod = NCT6694_RPT_MOD,
+                       .offset = cpu_to_le16(NCT6694_TIN_STS(channel / 8)),
+                       .len = cpu_to_le16(sizeof(data->rpt->status))
+               };
+               ret = nct6694_read_msg(data->nct6694, &cmd_hd,
+                                      &data->rpt->status);
+               if (ret)
+                       return ret;
+
+               *val = !!(data->rpt->status & BIT(channel % 8));
+
+               return 0;
+       default:
+               return -EOPNOTSUPP;
+       }
+}
+
+static int nct6694_fan_read(struct device *dev, u32 attr, int channel,
+                           long *val)
+{
+       struct nct6694_hwmon_data *data = dev_get_drvdata(dev);
+       struct nct6694_cmd_header cmd_hd;
+       unsigned char fanin_en;
+       int ret;
+
+       guard(mutex)(&data->lock);
+
+       switch (attr) {
+       case hwmon_fan_enable:
+               fanin_en = data->hwmon_en.fin_en[channel / 8];
+               *val = !!(fanin_en & BIT(channel % 8));
+
+               return 0;
+       case hwmon_fan_input:
+               cmd_hd = (struct nct6694_cmd_header) {
+                       .mod = NCT6694_RPT_MOD,
+                       .offset = cpu_to_le16(NCT6694_FIN_IDX(channel)),
+                       .len = cpu_to_le16(sizeof(data->rpt->fin))
+               };
+               ret = nct6694_read_msg(data->nct6694, &cmd_hd,
+                                      &data->rpt->fin);
+               if (ret)
+                       return ret;
+
+               *val = be16_to_cpu(data->rpt->fin);
+
+               return 0;
+       case hwmon_fan_min:
+               cmd_hd = (struct nct6694_cmd_header) {
+                       .mod = NCT6694_HWMON_MOD,
+                       .cmd = NCT6694_HWMON_ALARM,
+                       .sel = NCT6694_HWMON_ALARM_SEL,
+                       .len = cpu_to_le16(sizeof(data->msg->hwmon_alarm))
+               };
+               ret = nct6694_read_msg(data->nct6694, &cmd_hd,
+                                      &data->msg->hwmon_alarm);
+               if (ret)
+                       return ret;
+
+               *val = be16_to_cpu(data->msg->hwmon_alarm.fin_ll[channel]);
+
+               return 0;
+       case hwmon_fan_min_alarm:
+               cmd_hd = (struct nct6694_cmd_header) {
+                       .mod = NCT6694_RPT_MOD,
+                       .offset = cpu_to_le16(NCT6694_FIN_STS(channel / 8)),
+                       .len = cpu_to_le16(sizeof(data->rpt->status))
+               };
+               ret = nct6694_read_msg(data->nct6694, &cmd_hd,
+                                      &data->rpt->status);
+               if (ret)
+                       return ret;
+
+               *val = !!(data->rpt->status & BIT(channel % 8));
+
+               return 0;
+       default:
+               return -EOPNOTSUPP;
+       }
+}
+
+static int nct6694_pwm_read(struct device *dev, u32 attr, int channel,
+                           long *val)
+{
+       struct nct6694_hwmon_data *data = dev_get_drvdata(dev);
+       struct nct6694_cmd_header cmd_hd;
+       unsigned char pwm_en;
+       int ret;
+
+       guard(mutex)(&data->lock);
+
+       switch (attr) {
+       case hwmon_pwm_enable:
+               pwm_en = data->hwmon_en.pwm_en[channel / 8];
+               *val = !!(pwm_en & BIT(channel % 8));
+
+               return 0;
+       case hwmon_pwm_input:
+               cmd_hd = (struct nct6694_cmd_header) {
+                       .mod = NCT6694_RPT_MOD,
+                       .offset = cpu_to_le16(NCT6694_PWM_IDX(channel)),
+                       .len = cpu_to_le16(sizeof(data->rpt->pwm))
+               };
+               ret = nct6694_read_msg(data->nct6694, &cmd_hd,
+                                      &data->rpt->pwm);
+               if (ret)
+                       return ret;
+
+               *val = data->rpt->pwm;
+
+               return 0;
+       case hwmon_pwm_freq:
+               *val = NCT6694_FREQ_FROM_REG(data->hwmon_en.pwm_freq[channel]);
+
+               return 0;
+       default:
+               return -EOPNOTSUPP;
+       }
+}
+
+static int nct6694_in_write(struct device *dev, u32 attr, int channel,
+                           long val)
+{
+       struct nct6694_hwmon_data *data = dev_get_drvdata(dev);
+       struct nct6694_cmd_header cmd_hd;
+       int ret;
+
+       guard(mutex)(&data->lock);
+
+       switch (attr) {
+       case hwmon_in_enable:
+               if (val == 0)
+                       data->hwmon_en.vin_en[channel / 8] &= ~BIT(channel % 8);
+               else if (val == 1)
+                       data->hwmon_en.vin_en[channel / 8] |= BIT(channel % 8);
+               else
+                       return -EINVAL;
+
+               cmd_hd = (struct nct6694_cmd_header) {
+                       .mod = NCT6694_HWMON_MOD,
+                       .cmd = NCT6694_HWMON_CONTROL,
+                       .sel = NCT6694_HWMON_CONTROL_SEL,
+                       .len = cpu_to_le16(sizeof(data->hwmon_en))
+               };
+
+               return nct6694_write_msg(data->nct6694, &cmd_hd,
+                                        &data->hwmon_en);
+       case hwmon_in_max:
+               cmd_hd = (struct nct6694_cmd_header) {
+                       .mod = NCT6694_HWMON_MOD,
+                       .cmd = NCT6694_HWMON_ALARM,
+                       .sel = NCT6694_HWMON_ALARM_SEL,
+                       .len = cpu_to_le16(sizeof(data->msg->hwmon_alarm))
+               };
+               ret = nct6694_read_msg(data->nct6694, &cmd_hd,
+                                      &data->msg->hwmon_alarm);
+               if (ret)
+                       return ret;
+
+               val = clamp_val(val, 0, 2032);
+               data->msg->hwmon_alarm.vin_limit[channel].hl = in_to_reg(val);
+
+               return nct6694_write_msg(data->nct6694, &cmd_hd,
+                                        &data->msg->hwmon_alarm);
+       case hwmon_in_min:
+               cmd_hd = (struct nct6694_cmd_header) {
+                       .mod = NCT6694_HWMON_MOD,
+                       .cmd = NCT6694_HWMON_ALARM,
+                       .sel = NCT6694_HWMON_ALARM_SEL,
+                       .len = cpu_to_le16(sizeof(data->msg->hwmon_alarm))
+               };
+               ret = nct6694_read_msg(data->nct6694, &cmd_hd,
+                                      &data->msg->hwmon_alarm);
+               if (ret)
+                       return ret;
+
+               val = clamp_val(val, 0, 2032);
+               data->msg->hwmon_alarm.vin_limit[channel].ll = in_to_reg(val);
+
+               return nct6694_write_msg(data->nct6694, &cmd_hd,
+                                        &data->msg->hwmon_alarm);
+       default:
+               return -EOPNOTSUPP;
+       }
+}
+
+static int nct6694_temp_write(struct device *dev, u32 attr, int channel,
+                             long val)
+{
+       struct nct6694_hwmon_data *data = dev_get_drvdata(dev);
+       struct nct6694_cmd_header cmd_hd;
+       unsigned char temp_hyst;
+       signed char temp_max;
+       int ret;
+
+       guard(mutex)(&data->lock);
+
+       switch (attr) {
+       case hwmon_temp_enable:
+               if (val == 0)
+                       data->hwmon_en.tin_en[channel / 8] &= ~BIT(channel % 8);
+               else if (val == 1)
+                       data->hwmon_en.tin_en[channel / 8] |= BIT(channel % 8);
+               else
+                       return -EINVAL;
+
+               cmd_hd = (struct nct6694_cmd_header) {
+                       .mod = NCT6694_HWMON_MOD,
+                       .cmd = NCT6694_HWMON_CONTROL,
+                       .sel = NCT6694_HWMON_CONTROL_SEL,
+                       .len = cpu_to_le16(sizeof(data->hwmon_en))
+               };
+
+               return nct6694_write_msg(data->nct6694, &cmd_hd,
+                                        &data->hwmon_en);
+       case hwmon_temp_max:
+               cmd_hd = (struct nct6694_cmd_header) {
+                       .mod = NCT6694_HWMON_MOD,
+                       .cmd = NCT6694_HWMON_ALARM,
+                       .sel = NCT6694_HWMON_ALARM_SEL,
+                       .len = cpu_to_le16(sizeof(data->msg->hwmon_alarm))
+               };
+               ret = nct6694_read_msg(data->nct6694, &cmd_hd,
+                                      &data->msg->hwmon_alarm);
+               if (ret)
+                       return ret;
+
+               val = clamp_val(val, -127000, 127000);
+               data->msg->hwmon_alarm.tin_cfg[channel].hl = temp_to_reg(val);
+
+               return nct6694_write_msg(data->nct6694, &cmd_hd,
+                                        &data->msg->hwmon_alarm);
+       case hwmon_temp_max_hyst:
+               cmd_hd = (struct nct6694_cmd_header) {
+                       .mod = NCT6694_HWMON_MOD,
+                       .cmd = NCT6694_HWMON_ALARM,
+                       .sel = NCT6694_HWMON_ALARM_SEL,
+                       .len = cpu_to_le16(sizeof(data->msg->hwmon_alarm))
+               };
+               ret = nct6694_read_msg(data->nct6694, &cmd_hd,
+                                      &data->msg->hwmon_alarm);
+
+               val = clamp_val(val, -127000, 127000);
+               temp_max = data->msg->hwmon_alarm.tin_cfg[channel].hl;
+               temp_hyst = temp_max - temp_to_reg(val);
+               temp_hyst = clamp_val(temp_hyst, 0, 7);
+               data->msg->hwmon_alarm.tin_cfg[channel].hyst =
+                       (data->msg->hwmon_alarm.tin_cfg[channel].hyst & ~NCT6694_TIN_HYST_MASK) |
+                       FIELD_PREP(NCT6694_TIN_HYST_MASK, temp_hyst);
+
+               return nct6694_write_msg(data->nct6694, &cmd_hd,
+                                        &data->msg->hwmon_alarm);
+       default:
+               return -EOPNOTSUPP;
+       }
+}
+
+static int nct6694_fan_write(struct device *dev, u32 attr, int channel,
+                            long val)
+{
+       struct nct6694_hwmon_data *data = dev_get_drvdata(dev);
+       struct nct6694_cmd_header cmd_hd;
+       int ret;
+
+       guard(mutex)(&data->lock);
+
+       switch (attr) {
+       case hwmon_fan_enable:
+               if (val == 0)
+                       data->hwmon_en.fin_en[channel / 8] &= ~BIT(channel % 8);
+               else if (val == 1)
+                       data->hwmon_en.fin_en[channel / 8] |= BIT(channel % 8);
+               else
+                       return -EINVAL;
+
+               cmd_hd = (struct nct6694_cmd_header) {
+                       .mod = NCT6694_HWMON_MOD,
+                       .cmd = NCT6694_HWMON_CONTROL,
+                       .sel = NCT6694_HWMON_CONTROL_SEL,
+                       .len = cpu_to_le16(sizeof(data->hwmon_en))
+               };
+
+               return nct6694_write_msg(data->nct6694, &cmd_hd,
+                                        &data->hwmon_en);
+       case hwmon_fan_min:
+               cmd_hd = (struct nct6694_cmd_header) {
+                       .mod = NCT6694_HWMON_MOD,
+                       .cmd = NCT6694_HWMON_ALARM,
+                       .sel = NCT6694_HWMON_ALARM_SEL,
+                       .len = cpu_to_le16(sizeof(data->msg->hwmon_alarm))
+               };
+               ret = nct6694_read_msg(data->nct6694, &cmd_hd,
+                                      &data->msg->hwmon_alarm);
+               if (ret)
+                       return ret;
+
+               val = clamp_val(val, 1, 65535);
+               data->msg->hwmon_alarm.fin_ll[channel] = cpu_to_be16(val);
+
+               return nct6694_write_msg(data->nct6694, &cmd_hd,
+                                        &data->msg->hwmon_alarm);
+       default:
+               return -EOPNOTSUPP;
+       }
+}
+
+static int nct6694_pwm_write(struct device *dev, u32 attr, int channel,
+                            long val)
+{
+       struct nct6694_hwmon_data *data = dev_get_drvdata(dev);
+       struct nct6694_cmd_header cmd_hd;
+       int ret;
+
+       guard(mutex)(&data->lock);
+
+       switch (attr) {
+       case hwmon_pwm_enable:
+               if (val == 0)
+                       data->hwmon_en.pwm_en[channel / 8] &= ~BIT(channel % 8);
+               else if (val == 1)
+                       data->hwmon_en.pwm_en[channel / 8] |= BIT(channel % 8);
+               else
+                       return -EINVAL;
+
+               cmd_hd = (struct nct6694_cmd_header) {
+                       .mod = NCT6694_HWMON_MOD,
+                       .cmd = NCT6694_HWMON_CONTROL,
+                       .sel = NCT6694_HWMON_CONTROL_SEL,
+                       .len = cpu_to_le16(sizeof(data->hwmon_en))
+               };
+
+               return nct6694_write_msg(data->nct6694, &cmd_hd,
+                                        &data->hwmon_en);
+       case hwmon_pwm_input:
+               if (val < 0 || val > 255)
+                       return -EINVAL;
+
+               cmd_hd = (struct nct6694_cmd_header) {
+                       .mod = NCT6694_PWM_MOD,
+                       .cmd = NCT6694_PWM_CONTROL,
+                       .sel = NCT6694_PWM_CONTROL_SEL,
+                       .len = cpu_to_le16(sizeof(data->msg->pwm_ctrl))
+               };
+
+               ret = nct6694_read_msg(data->nct6694, &cmd_hd,
+                                      &data->msg->pwm_ctrl);
+               if (ret)
+                       return ret;
+
+               data->msg->pwm_ctrl.mal_val[channel] = val;
+
+               return nct6694_write_msg(data->nct6694, &cmd_hd,
+                                        &data->msg->pwm_ctrl);
+       case hwmon_pwm_freq:
+               cmd_hd = (struct nct6694_cmd_header) {
+                       .mod = NCT6694_HWMON_MOD,
+                       .cmd = NCT6694_HWMON_CONTROL,
+                       .sel = NCT6694_HWMON_CONTROL_SEL,
+                       .len = cpu_to_le16(sizeof(data->hwmon_en))
+               };
+
+               data->hwmon_en.pwm_freq[channel] = NCT6694_FREQ_TO_REG(val);
+
+               return nct6694_write_msg(data->nct6694, &cmd_hd,
+                                        &data->hwmon_en);
+       default:
+               return -EOPNOTSUPP;
+       }
+}
+
+static int nct6694_read(struct device *dev, enum hwmon_sensor_types type,
+                       u32 attr, int channel, long *val)
+{
+       switch (type) {
+       case hwmon_in:
+               /* in mV */
+               return nct6694_in_read(dev, attr, channel, val);
+       case hwmon_temp:
+               /* in mC */
+               return nct6694_temp_read(dev, attr, channel, val);
+       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;
+       }
+}
+
+static int nct6694_write(struct device *dev, enum hwmon_sensor_types type,
+                        u32 attr, int channel, long val)
+{
+       switch (type) {
+       case hwmon_in:
+               return nct6694_in_write(dev, attr, channel, val);
+       case hwmon_temp:
+               return nct6694_temp_write(dev, attr, channel, val);
+       case hwmon_fan:
+               return nct6694_fan_write(dev, attr, channel, val);
+       case hwmon_pwm:
+               return nct6694_pwm_write(dev, attr, channel, val);
+       default:
+               return -EOPNOTSUPP;
+       }
+}
+
+static umode_t nct6694_is_visible(const void *data,
+                                 enum hwmon_sensor_types type,
+                                 u32 attr, int channel)
+{
+       switch (type) {
+       case hwmon_in:
+               switch (attr) {
+               case hwmon_in_enable:
+               case hwmon_in_max:
+               case hwmon_in_min:
+                       return 0644;
+               case hwmon_in_alarm:
+               case hwmon_in_input:
+                       return 0444;
+               default:
+                       return 0;
+               }
+       case hwmon_temp:
+               switch (attr) {
+               case hwmon_temp_enable:
+               case hwmon_temp_max:
+               case hwmon_temp_max_hyst:
+                       return 0644;
+               case hwmon_temp_input:
+               case hwmon_temp_max_alarm:
+                       return 0444;
+               default:
+                       return 0;
+               }
+       case hwmon_fan:
+               switch (attr) {
+               case hwmon_fan_enable:
+               case hwmon_fan_min:
+                       return 0644;
+               case hwmon_fan_input:
+               case hwmon_fan_min_alarm:
+                       return 0444;
+               default:
+                       return 0;
+               }
+       case hwmon_pwm:
+               switch (attr) {
+               case hwmon_pwm_enable:
+               case hwmon_pwm_freq:
+               case hwmon_pwm_input:
+                       return 0644;
+               default:
+                       return 0;
+               }
+       default:
+               return 0;
+       }
+}
+
+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)
+{
+       struct nct6694_cmd_header cmd_hd = {
+               .mod = NCT6694_HWMON_MOD,
+               .cmd = NCT6694_HWMON_CONTROL,
+               .sel = NCT6694_HWMON_CONTROL_SEL,
+               .len = cpu_to_le16(sizeof(data->hwmon_en))
+       };
+       int ret;
+
+       /*
+        * Record each Hardware Monitor Channel enable status
+        * and PWM frequency register
+        */
+       ret = nct6694_read_msg(data->nct6694, &cmd_hd,
+                              &data->hwmon_en);
+       if (ret)
+               return ret;
+
+       cmd_hd = (struct nct6694_cmd_header) {
+               .mod = NCT6694_HWMON_MOD,
+               .cmd = NCT6694_HWMON_ALARM,
+               .sel = NCT6694_HWMON_ALARM_SEL,
+               .len = cpu_to_le16(sizeof(data->msg->hwmon_alarm))
+       };
+
+       /* Select hwmon device alarm mode */
+       ret = nct6694_read_msg(data->nct6694, &cmd_hd,
+                              &data->msg->hwmon_alarm);
+       if (ret)
+               return ret;
+
+       data->msg->hwmon_alarm.smi_ctrl = NCT6694_HWMON_REALTIME_IRQ;
+
+       return nct6694_write_msg(data->nct6694, &cmd_hd,
+                                &data->msg->hwmon_alarm);
+}
+
+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->rpt = devm_kzalloc(&pdev->dev, sizeof(union nct6694_hwmon_rpt),
+                                GFP_KERNEL);
+       if (!data->rpt)
+               return -ENOMEM;
+
+       data->msg = devm_kzalloc(&pdev->dev, sizeof(union nct6694_hwmon_msg),
+                                GFP_KERNEL);
+       if (!data->msg)
+               return -ENOMEM;
+
+       data->nct6694 = nct6694;
+       ret = devm_mutex_init(&pdev->dev, &data->lock);
+       if (ret)
+               return ret;
+
+       ret = nct6694_hwmon_init(data);
+       if (ret)
+               return ret;
+
+       /* Register hwmon device to HWMON framework */
+       hwmon_dev = devm_hwmon_device_register_with_info(&pdev->dev,
+                                                        "nct6694", data,
+                                                        &nct6694_chip_info,
+                                                        NULL);
+       return PTR_ERR_OR_ZERO(hwmon_dev);
+}
+
+static struct platform_driver nct6694_hwmon_driver = {
+       .driver = {
+               .name   = "nct6694-hwmon",
+       },
+       .probe          = nct6694_hwmon_probe,
+};
+
+module_platform_driver(nct6694_hwmon_driver);
+
+MODULE_DESCRIPTION("USB-HWMON driver for NCT6694");
+MODULE_AUTHOR("Ming Yu <tmyu0@nuvoton.com>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:nct6694-hwmon");