Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1184 insertions, 0 deletions

diff --git a/drivers/hwmon/nct7904.c b/drivers/hwmon/nct7904.c
new file mode 100644
index 000000000..b1c837fc4
--- /dev/null
+++ b/drivers/hwmon/nct7904.c
@@ -0,0 +1,1184 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * nct7904.c - driver for Nuvoton NCT7904D.
+ *
+ * Copyright (c) 2015 Kontron
+ * Author: Vadim V. Vlasov <vvlasov@dev.rtsoft.ru>
+ *
+ * Copyright (c) 2019 Advantech
+ * Author: Amy.Shih <amy.shih@advantech.com.tw>
+ *
+ * Copyright (c) 2020 Advantech
+ * Author: Yuechao Zhao <yuechao.zhao@advantech.com.cn>
+ *
+ * Supports the following chips:
+ *
+ * Chip        #vin  #fan  #pwm  #temp  #dts  chip ID
+ * nct7904d     20    12    4     5      8    0xc5
+ */
+
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/i2c.h>
+#include <linux/mutex.h>
+#include <linux/hwmon.h>
+#include <linux/watchdog.h>
+
+#define VENDOR_ID_REG		0x7A	/* Any bank */
+#define NUVOTON_ID		0x50
+#define CHIP_ID_REG		0x7B	/* Any bank */
+#define NCT7904_ID		0xC5
+#define DEVICE_ID_REG		0x7C	/* Any bank */
+
+#define BANK_SEL_REG		0xFF
+#define BANK_0			0x00
+#define BANK_1			0x01
+#define BANK_2			0x02
+#define BANK_3			0x03
+#define BANK_4			0x04
+#define BANK_MAX		0x04
+
+#define FANIN_MAX		12	/* Counted from 1 */
+#define VSEN_MAX		21	/* VSEN1..14, 3VDD, VBAT, V3VSB,
+					   LTD (not a voltage), VSEN17..19 */
+#define FANCTL_MAX		4	/* Counted from 1 */
+#define TCPU_MAX		8	/* Counted from 1 */
+#define TEMP_MAX		4	/* Counted from 1 */
+#define SMI_STS_MAX		10	/* Counted from 1 */
+
+#define VT_ADC_CTRL0_REG	0x20	/* Bank 0 */
+#define VT_ADC_CTRL1_REG	0x21	/* Bank 0 */
+#define VT_ADC_CTRL2_REG	0x22	/* Bank 0 */
+#define FANIN_CTRL0_REG		0x24
+#define FANIN_CTRL1_REG		0x25
+#define DTS_T_CTRL0_REG		0x26
+#define DTS_T_CTRL1_REG		0x27
+#define VT_ADC_MD_REG		0x2E
+
+#define VSEN1_HV_LL_REG		0x02	/* Bank 1; 2 regs (HV/LV) per sensor */
+#define VSEN1_LV_LL_REG		0x03	/* Bank 1; 2 regs (HV/LV) per sensor */
+#define VSEN1_HV_HL_REG		0x00	/* Bank 1; 2 regs (HV/LV) per sensor */
+#define VSEN1_LV_HL_REG		0x01	/* Bank 1; 2 regs (HV/LV) per sensor */
+#define SMI_STS1_REG		0xC1	/* Bank 0; SMI Status Register */
+#define SMI_STS3_REG		0xC3	/* Bank 0; SMI Status Register */
+#define SMI_STS5_REG		0xC5	/* Bank 0; SMI Status Register */
+#define SMI_STS7_REG		0xC7	/* Bank 0; SMI Status Register */
+#define SMI_STS8_REG		0xC8	/* Bank 0; SMI Status Register */
+
+#define VSEN1_HV_REG		0x40	/* Bank 0; 2 regs (HV/LV) per sensor */
+#define TEMP_CH1_HV_REG		0x42	/* Bank 0; same as VSEN2_HV */
+#define LTD_HV_REG		0x62	/* Bank 0; 2 regs in VSEN range */
+#define LTD_HV_HL_REG		0x44	/* Bank 1; 1 reg for LTD */
+#define LTD_LV_HL_REG		0x45	/* Bank 1; 1 reg for LTD */
+#define LTD_HV_LL_REG		0x46	/* Bank 1; 1 reg for LTD */
+#define LTD_LV_LL_REG		0x47	/* Bank 1; 1 reg for LTD */
+#define TEMP_CH1_CH_REG		0x05	/* Bank 1; 1 reg for LTD */
+#define TEMP_CH1_W_REG		0x06	/* Bank 1; 1 reg for LTD */
+#define TEMP_CH1_WH_REG		0x07	/* Bank 1; 1 reg for LTD */
+#define TEMP_CH1_C_REG		0x04	/* Bank 1; 1 reg per sensor */
+#define DTS_T_CPU1_C_REG	0x90	/* Bank 1; 1 reg per sensor */
+#define DTS_T_CPU1_CH_REG	0x91	/* Bank 1; 1 reg per sensor */
+#define DTS_T_CPU1_W_REG	0x92	/* Bank 1; 1 reg per sensor */
+#define DTS_T_CPU1_WH_REG	0x93	/* Bank 1; 1 reg per sensor */
+#define FANIN1_HV_REG		0x80	/* Bank 0; 2 regs (HV/LV) per sensor */
+#define FANIN1_HV_HL_REG	0x60	/* Bank 1; 2 regs (HV/LV) per sensor */
+#define FANIN1_LV_HL_REG	0x61	/* Bank 1; 2 regs (HV/LV) per sensor */
+#define T_CPU1_HV_REG		0xA0	/* Bank 0; 2 regs (HV/LV) per sensor */
+
+#define PRTS_REG		0x03	/* Bank 2 */
+#define PFE_REG			0x00	/* Bank 2; PECI Function Enable */
+#define TSI_CTRL_REG		0x50	/* Bank 2; TSI Control Register */
+#define FANCTL1_FMR_REG		0x00	/* Bank 3; 1 reg per channel */
+#define FANCTL1_OUT_REG		0x10	/* Bank 3; 1 reg per channel */
+
+#define WDT_LOCK_REG		0xE0	/* W/O Lock Watchdog Register */
+#define WDT_EN_REG		0xE1	/* R/O Watchdog Enable Register */
+#define WDT_STS_REG		0xE2	/* R/O Watchdog Status Register */
+#define WDT_TIMER_REG		0xE3	/* R/W Watchdog Timer Register */
+#define WDT_SOFT_EN		0x55	/* Enable soft watchdog timer */
+#define WDT_SOFT_DIS		0xAA	/* Disable soft watchdog timer */
+
+#define VOLT_MONITOR_MODE	0x0
+#define THERMAL_DIODE_MODE	0x1
+#define THERMISTOR_MODE		0x3
+
+#define ENABLE_TSI	BIT(1)
+
+#define WATCHDOG_TIMEOUT	1	/* 1 minute default timeout */
+
+/*The timeout range is 1-255 minutes*/
+#define MIN_TIMEOUT		(1 * 60)
+#define MAX_TIMEOUT		(255 * 60)
+
+static int timeout;
+module_param(timeout, int, 0);
+MODULE_PARM_DESC(timeout, "Watchdog timeout in minutes. 1 <= timeout <= 255, default="
+			__MODULE_STRING(WATCHDOG_TIMEOUT) ".");
+
+static bool nowayout = WATCHDOG_NOWAYOUT;
+module_param(nowayout, bool, 0);
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
+			__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
+
+static const unsigned short normal_i2c[] = {
+	0x2d, 0x2e, I2C_CLIENT_END
+};
+
+struct nct7904_data {
+	struct i2c_client *client;
+	struct watchdog_device wdt;
+	struct mutex bank_lock;
+	int bank_sel;
+	u32 fanin_mask;
+	u32 vsen_mask;
+	u32 tcpu_mask;
+	u8 fan_mode[FANCTL_MAX];
+	u8 enable_dts;
+	u8 has_dts;
+	u8 temp_mode; /* 0: TR mode, 1: TD mode */
+	u8 fan_alarm[2];
+	u8 vsen_alarm[3];
+};
+
+/* Access functions */
+static int nct7904_bank_lock(struct nct7904_data *data, unsigned int bank)
+{
+	int ret;
+
+	mutex_lock(&data->bank_lock);
+	if (data->bank_sel == bank)
+		return 0;
+	ret = i2c_smbus_write_byte_data(data->client, BANK_SEL_REG, bank);
+	if (ret == 0)
+		data->bank_sel = bank;
+	else
+		data->bank_sel = -1;
+	return ret;
+}
+
+static inline void nct7904_bank_release(struct nct7904_data *data)
+{
+	mutex_unlock(&data->bank_lock);
+}
+
+/* Read 1-byte register. Returns unsigned reg or -ERRNO on error. */
+static int nct7904_read_reg(struct nct7904_data *data,
+			    unsigned int bank, unsigned int reg)
+{
+	struct i2c_client *client = data->client;
+	int ret;
+
+	ret = nct7904_bank_lock(data, bank);
+	if (ret == 0)
+		ret = i2c_smbus_read_byte_data(client, reg);
+
+	nct7904_bank_release(data);
+	return ret;
+}
+
+/*
+ * Read 2-byte register. Returns register in big-endian format or
+ * -ERRNO on error.
+ */
+static int nct7904_read_reg16(struct nct7904_data *data,
+			      unsigned int bank, unsigned int reg)
+{
+	struct i2c_client *client = data->client;
+	int ret, hi;
+
+	ret = nct7904_bank_lock(data, bank);
+	if (ret == 0) {
+		ret = i2c_smbus_read_byte_data(client, reg);
+		if (ret >= 0) {
+			hi = ret;
+			ret = i2c_smbus_read_byte_data(client, reg + 1);
+			if (ret >= 0)
+				ret |= hi << 8;
+		}
+	}
+
+	nct7904_bank_release(data);
+	return ret;
+}
+
+/* Write 1-byte register. Returns 0 or -ERRNO on error. */
+static int nct7904_write_reg(struct nct7904_data *data,
+			     unsigned int bank, unsigned int reg, u8 val)
+{
+	struct i2c_client *client = data->client;
+	int ret;
+
+	ret = nct7904_bank_lock(data, bank);
+	if (ret == 0)
+		ret = i2c_smbus_write_byte_data(client, reg, val);
+
+	nct7904_bank_release(data);
+	return ret;
+}
+
+static int nct7904_read_fan(struct device *dev, u32 attr, int channel,
+			    long *val)
+{
+	struct nct7904_data *data = dev_get_drvdata(dev);
+	unsigned int cnt, rpm;
+	int ret;
+
+	switch (attr) {
+	case hwmon_fan_input:
+		ret = nct7904_read_reg16(data, BANK_0,
+					 FANIN1_HV_REG + channel * 2);
+		if (ret < 0)
+			return ret;
+		cnt = ((ret & 0xff00) >> 3) | (ret & 0x1f);
+		if (cnt == 0 || cnt == 0x1fff)
+			rpm = 0;
+		else
+			rpm = 1350000 / cnt;
+		*val = rpm;
+		return 0;
+	case hwmon_fan_min:
+		ret = nct7904_read_reg16(data, BANK_1,
+					 FANIN1_HV_HL_REG + channel * 2);
+		if (ret < 0)
+			return ret;
+		cnt = ((ret & 0xff00) >> 3) | (ret & 0x1f);
+		if (cnt == 0 || cnt == 0x1fff)
+			rpm = 0;
+		else
+			rpm = 1350000 / cnt;
+		*val = rpm;
+		return 0;
+	case hwmon_fan_alarm:
+		ret = nct7904_read_reg(data, BANK_0,
+				       SMI_STS5_REG + (channel >> 3));
+		if (ret < 0)
+			return ret;
+		if (!data->fan_alarm[channel >> 3])
+			data->fan_alarm[channel >> 3] = ret & 0xff;
+		else
+			/* If there is new alarm showing up */
+			data->fan_alarm[channel >> 3] |= (ret & 0xff);
+		*val = (data->fan_alarm[channel >> 3] >> (channel & 0x07)) & 1;
+		/* Needs to clean the alarm if alarm existing */
+		if (*val)
+			data->fan_alarm[channel >> 3] ^= 1 << (channel & 0x07);
+		return 0;
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static umode_t nct7904_fan_is_visible(const void *_data, u32 attr, int channel)
+{
+	const struct nct7904_data *data = _data;
+
+	switch (attr) {
+	case hwmon_fan_input:
+	case hwmon_fan_alarm:
+		if (data->fanin_mask & (1 << channel))
+			return 0444;
+		break;
+	case hwmon_fan_min:
+		if (data->fanin_mask & (1 << channel))
+			return 0644;
+		break;
+	default:
+		break;
+	}
+
+	return 0;
+}
+
+static u8 nct7904_chan_to_index[] = {
+	0,	/* Not used */
+	0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
+	18, 19, 20, 16
+};
+
+static int nct7904_read_in(struct device *dev, u32 attr, int channel,
+			   long *val)
+{
+	struct nct7904_data *data = dev_get_drvdata(dev);
+	int ret, volt, index;
+
+	index = nct7904_chan_to_index[channel];
+
+	switch (attr) {
+	case hwmon_in_input:
+		ret = nct7904_read_reg16(data, BANK_0,
+					 VSEN1_HV_REG + index * 2);
+		if (ret < 0)
+			return ret;
+		volt = ((ret & 0xff00) >> 5) | (ret & 0x7);
+		if (index < 14)
+			volt *= 2; /* 0.002V scale */
+		else
+			volt *= 6; /* 0.006V scale */
+		*val = volt;
+		return 0;
+	case hwmon_in_min:
+		ret = nct7904_read_reg16(data, BANK_1,
+					 VSEN1_HV_LL_REG + index * 4);
+		if (ret < 0)
+			return ret;
+		volt = ((ret & 0xff00) >> 5) | (ret & 0x7);
+		if (index < 14)
+			volt *= 2; /* 0.002V scale */
+		else
+			volt *= 6; /* 0.006V scale */
+		*val = volt;
+		return 0;
+	case hwmon_in_max:
+		ret = nct7904_read_reg16(data, BANK_1,
+					 VSEN1_HV_HL_REG + index * 4);
+		if (ret < 0)
+			return ret;
+		volt = ((ret & 0xff00) >> 5) | (ret & 0x7);
+		if (index < 14)
+			volt *= 2; /* 0.002V scale */
+		else
+			volt *= 6; /* 0.006V scale */
+		*val = volt;
+		return 0;
+	case hwmon_in_alarm:
+		ret = nct7904_read_reg(data, BANK_0,
+				       SMI_STS1_REG + (index >> 3));
+		if (ret < 0)
+			return ret;
+		if (!data->vsen_alarm[index >> 3])
+			data->vsen_alarm[index >> 3] = ret & 0xff;
+		else
+			/* If there is new alarm showing up */
+			data->vsen_alarm[index >> 3] |= (ret & 0xff);
+		*val = (data->vsen_alarm[index >> 3] >> (index & 0x07)) & 1;
+		/* Needs to clean the alarm if alarm existing */
+		if (*val)
+			data->vsen_alarm[index >> 3] ^= 1 << (index & 0x07);
+		return 0;
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static umode_t nct7904_in_is_visible(const void *_data, u32 attr, int channel)
+{
+	const struct nct7904_data *data = _data;
+	int index = nct7904_chan_to_index[channel];
+
+	switch (attr) {
+	case hwmon_in_input:
+	case hwmon_in_alarm:
+		if (channel > 0 && (data->vsen_mask & BIT(index)))
+			return 0444;
+		break;
+	case hwmon_in_min:
+	case hwmon_in_max:
+		if (channel > 0 && (data->vsen_mask & BIT(index)))
+			return 0644;
+		break;
+	default:
+		break;
+	}
+
+	return 0;
+}
+
+static int nct7904_read_temp(struct device *dev, u32 attr, int channel,
+			     long *val)
+{
+	struct nct7904_data *data = dev_get_drvdata(dev);
+	int ret, temp;
+	unsigned int reg1, reg2, reg3;
+	s8 temps;
+
+	switch (attr) {
+	case hwmon_temp_input:
+		if (channel == 4)
+			ret = nct7904_read_reg16(data, BANK_0, LTD_HV_REG);
+		else if (channel < 5)
+			ret = nct7904_read_reg16(data, BANK_0,
+						 TEMP_CH1_HV_REG + channel * 4);
+		else
+			ret = nct7904_read_reg16(data, BANK_0,
+						 T_CPU1_HV_REG + (channel - 5)
+						 * 2);
+		if (ret < 0)
+			return ret;
+		temp = ((ret & 0xff00) >> 5) | (ret & 0x7);
+		*val = sign_extend32(temp, 10) * 125;
+		return 0;
+	case hwmon_temp_alarm:
+		if (channel == 4) {
+			ret = nct7904_read_reg(data, BANK_0,
+					       SMI_STS3_REG);
+			if (ret < 0)
+				return ret;
+			*val = (ret >> 1) & 1;
+		} else if (channel < 4) {
+			ret = nct7904_read_reg(data, BANK_0,
+					       SMI_STS1_REG);
+			if (ret < 0)
+				return ret;
+			*val = (ret >> (((channel * 2) + 1) & 0x07)) & 1;
+		} else {
+			if ((channel - 5) < 4) {
+				ret = nct7904_read_reg(data, BANK_0,
+						       SMI_STS7_REG +
+						       ((channel - 5) >> 3));
+				if (ret < 0)
+					return ret;
+				*val = (ret >> ((channel - 5) & 0x07)) & 1;
+			} else {
+				ret = nct7904_read_reg(data, BANK_0,
+						       SMI_STS8_REG +
+						       ((channel - 5) >> 3));
+				if (ret < 0)
+					return ret;
+				*val = (ret >> (((channel - 5) & 0x07) - 4))
+							& 1;
+			}
+		}
+		return 0;
+	case hwmon_temp_type:
+		if (channel < 5) {
+			if ((data->tcpu_mask >> channel) & 0x01) {
+				if ((data->temp_mode >> channel) & 0x01)
+					*val = 3; /* TD */
+				else
+					*val = 4; /* TR */
+			} else {
+				*val = 0;
+			}
+		} else {
+			if ((data->has_dts >> (channel - 5)) & 0x01) {
+				if (data->enable_dts & ENABLE_TSI)
+					*val = 5; /* TSI */
+				else
+					*val = 6; /* PECI */
+			} else {
+				*val = 0;
+			}
+		}
+		return 0;
+	case hwmon_temp_max:
+		reg1 = LTD_HV_LL_REG;
+		reg2 = TEMP_CH1_W_REG;
+		reg3 = DTS_T_CPU1_W_REG;
+		break;
+	case hwmon_temp_max_hyst:
+		reg1 = LTD_LV_LL_REG;
+		reg2 = TEMP_CH1_WH_REG;
+		reg3 = DTS_T_CPU1_WH_REG;
+		break;
+	case hwmon_temp_crit:
+		reg1 = LTD_HV_HL_REG;
+		reg2 = TEMP_CH1_C_REG;
+		reg3 = DTS_T_CPU1_C_REG;
+		break;
+	case hwmon_temp_crit_hyst:
+		reg1 = LTD_LV_HL_REG;
+		reg2 = TEMP_CH1_CH_REG;
+		reg3 = DTS_T_CPU1_CH_REG;
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	if (channel == 4)
+		ret = nct7904_read_reg(data, BANK_1, reg1);
+	else if (channel < 5)
+		ret = nct7904_read_reg(data, BANK_1,
+				       reg2 + channel * 8);
+	else
+		ret = nct7904_read_reg(data, BANK_1,
+				       reg3 + (channel - 5) * 4);
+
+	if (ret < 0)
+		return ret;
+	temps = ret;
+	*val = temps * 1000;
+	return 0;
+}
+
+static umode_t nct7904_temp_is_visible(const void *_data, u32 attr, int channel)
+{
+	const struct nct7904_data *data = _data;
+
+	switch (attr) {
+	case hwmon_temp_input:
+	case hwmon_temp_alarm:
+	case hwmon_temp_type:
+		if (channel < 5) {
+			if (data->tcpu_mask & BIT(channel))
+				return 0444;
+		} else {
+			if (data->has_dts & BIT(channel - 5))
+				return 0444;
+		}
+		break;
+	case hwmon_temp_max:
+	case hwmon_temp_max_hyst:
+	case hwmon_temp_crit:
+	case hwmon_temp_crit_hyst:
+		if (channel < 5) {
+			if (data->tcpu_mask & BIT(channel))
+				return 0644;
+		} else {
+			if (data->has_dts & BIT(channel - 5))
+				return 0644;
+		}
+		break;
+	default:
+		break;
+	}
+
+	return 0;
+}
+
+static int nct7904_read_pwm(struct device *dev, u32 attr, int channel,
+			    long *val)
+{
+	struct nct7904_data *data = dev_get_drvdata(dev);
+	int ret;
+
+	switch (attr) {
+	case hwmon_pwm_input:
+		ret = nct7904_read_reg(data, BANK_3, FANCTL1_OUT_REG + channel);
+		if (ret < 0)
+			return ret;
+		*val = ret;
+		return 0;
+	case hwmon_pwm_enable:
+		ret = nct7904_read_reg(data, BANK_3, FANCTL1_FMR_REG + channel);
+		if (ret < 0)
+			return ret;
+
+		*val = ret ? 2 : 1;
+		return 0;
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int nct7904_write_temp(struct device *dev, u32 attr, int channel,
+			      long val)
+{
+	struct nct7904_data *data = dev_get_drvdata(dev);
+	int ret;
+	unsigned int reg1, reg2, reg3;
+
+	val = clamp_val(val / 1000, -128, 127);
+
+	switch (attr) {
+	case hwmon_temp_max:
+		reg1 = LTD_HV_LL_REG;
+		reg2 = TEMP_CH1_W_REG;
+		reg3 = DTS_T_CPU1_W_REG;
+		break;
+	case hwmon_temp_max_hyst:
+		reg1 = LTD_LV_LL_REG;
+		reg2 = TEMP_CH1_WH_REG;
+		reg3 = DTS_T_CPU1_WH_REG;
+		break;
+	case hwmon_temp_crit:
+		reg1 = LTD_HV_HL_REG;
+		reg2 = TEMP_CH1_C_REG;
+		reg3 = DTS_T_CPU1_C_REG;
+		break;
+	case hwmon_temp_crit_hyst:
+		reg1 = LTD_LV_HL_REG;
+		reg2 = TEMP_CH1_CH_REG;
+		reg3 = DTS_T_CPU1_CH_REG;
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+	if (channel == 4)
+		ret = nct7904_write_reg(data, BANK_1, reg1, val);
+	else if (channel < 5)
+		ret = nct7904_write_reg(data, BANK_1,
+					reg2 + channel * 8, val);
+	else
+		ret = nct7904_write_reg(data, BANK_1,
+					reg3 + (channel - 5) * 4, val);
+
+	return ret;
+}
+
+static int nct7904_write_fan(struct device *dev, u32 attr, int channel,
+			     long val)
+{
+	struct nct7904_data *data = dev_get_drvdata(dev);
+	int ret;
+	u8 tmp;
+
+	switch (attr) {
+	case hwmon_fan_min:
+		if (val <= 0)
+			return -EINVAL;
+
+		val = clamp_val(DIV_ROUND_CLOSEST(1350000, val), 1, 0x1fff);
+		tmp = (val >> 5) & 0xff;
+		ret = nct7904_write_reg(data, BANK_1,
+					FANIN1_HV_HL_REG + channel * 2, tmp);
+		if (ret < 0)
+			return ret;
+		tmp = val & 0x1f;
+		ret = nct7904_write_reg(data, BANK_1,
+					FANIN1_LV_HL_REG + channel * 2, tmp);
+		return ret;
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int nct7904_write_in(struct device *dev, u32 attr, int channel,
+			    long val)
+{
+	struct nct7904_data *data = dev_get_drvdata(dev);
+	int ret, index, tmp;
+
+	index = nct7904_chan_to_index[channel];
+
+	if (index < 14)
+		val = val / 2; /* 0.002V scale */
+	else
+		val = val / 6; /* 0.006V scale */
+
+	val = clamp_val(val, 0, 0x7ff);
+
+	switch (attr) {
+	case hwmon_in_min:
+		tmp = nct7904_read_reg(data, BANK_1,
+				       VSEN1_LV_LL_REG + index * 4);
+		if (tmp < 0)
+			return tmp;
+		tmp &= ~0x7;
+		tmp |= val & 0x7;
+		ret = nct7904_write_reg(data, BANK_1,
+					VSEN1_LV_LL_REG + index * 4, tmp);
+		if (ret < 0)
+			return ret;
+		tmp = nct7904_read_reg(data, BANK_1,
+				       VSEN1_HV_LL_REG + index * 4);
+		if (tmp < 0)
+			return tmp;
+		tmp = (val >> 3) & 0xff;
+		ret = nct7904_write_reg(data, BANK_1,
+					VSEN1_HV_LL_REG + index * 4, tmp);
+		return ret;
+	case hwmon_in_max:
+		tmp = nct7904_read_reg(data, BANK_1,
+				       VSEN1_LV_HL_REG + index * 4);
+		if (tmp < 0)
+			return tmp;
+		tmp &= ~0x7;
+		tmp |= val & 0x7;
+		ret = nct7904_write_reg(data, BANK_1,
+					VSEN1_LV_HL_REG + index * 4, tmp);
+		if (ret < 0)
+			return ret;
+		tmp = nct7904_read_reg(data, BANK_1,
+				       VSEN1_HV_HL_REG + index * 4);
+		if (tmp < 0)
+			return tmp;
+		tmp = (val >> 3) & 0xff;
+		ret = nct7904_write_reg(data, BANK_1,
+					VSEN1_HV_HL_REG + index * 4, tmp);
+		return ret;
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int nct7904_write_pwm(struct device *dev, u32 attr, int channel,
+			     long val)
+{
+	struct nct7904_data *data = dev_get_drvdata(dev);
+	int ret;
+
+	switch (attr) {
+	case hwmon_pwm_input:
+		if (val < 0 || val > 255)
+			return -EINVAL;
+		ret = nct7904_write_reg(data, BANK_3, FANCTL1_OUT_REG + channel,
+					val);
+		return ret;
+	case hwmon_pwm_enable:
+		if (val < 1 || val > 2 ||
+		    (val == 2 && !data->fan_mode[channel]))
+			return -EINVAL;
+		ret = nct7904_write_reg(data, BANK_3, FANCTL1_FMR_REG + channel,
+					val == 2 ? data->fan_mode[channel] : 0);
+		return ret;
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static umode_t nct7904_pwm_is_visible(const void *_data, u32 attr, int channel)
+{
+	switch (attr) {
+	case hwmon_pwm_input:
+	case hwmon_pwm_enable:
+		return 0644;
+	default:
+		return 0;
+	}
+}
+
+static int nct7904_read(struct device *dev, enum hwmon_sensor_types type,
+			u32 attr, int channel, long *val)
+{
+	switch (type) {
+	case hwmon_in:
+		return nct7904_read_in(dev, attr, channel, val);
+	case hwmon_fan:
+		return nct7904_read_fan(dev, attr, channel, val);
+	case hwmon_pwm:
+		return nct7904_read_pwm(dev, attr, channel, val);
+	case hwmon_temp:
+		return nct7904_read_temp(dev, attr, channel, val);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int nct7904_write(struct device *dev, enum hwmon_sensor_types type,
+			 u32 attr, int channel, long val)
+{
+	switch (type) {
+	case hwmon_in:
+		return nct7904_write_in(dev, attr, channel, val);
+	case hwmon_fan:
+		return nct7904_write_fan(dev, attr, channel, val);
+	case hwmon_pwm:
+		return nct7904_write_pwm(dev, attr, channel, val);
+	case hwmon_temp:
+		return nct7904_write_temp(dev, attr, channel, val);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static umode_t nct7904_is_visible(const void *data,
+				  enum hwmon_sensor_types type,
+				  u32 attr, int channel)
+{
+	switch (type) {
+	case hwmon_in:
+		return nct7904_in_is_visible(data, attr, channel);
+	case hwmon_fan:
+		return nct7904_fan_is_visible(data, attr, channel);
+	case hwmon_pwm:
+		return nct7904_pwm_is_visible(data, attr, channel);
+	case hwmon_temp:
+		return nct7904_temp_is_visible(data, attr, channel);
+	default:
+		return 0;
+	}
+}
+
+/* Return 0 if detection is successful, -ENODEV otherwise */
+static int nct7904_detect(struct i2c_client *client,
+			  struct i2c_board_info *info)
+{
+	struct i2c_adapter *adapter = client->adapter;
+
+	if (!i2c_check_functionality(adapter,
+				     I2C_FUNC_SMBUS_READ_BYTE |
+				     I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
+		return -ENODEV;
+
+	/* Determine the chip type. */
+	if (i2c_smbus_read_byte_data(client, VENDOR_ID_REG) != NUVOTON_ID ||
+	    i2c_smbus_read_byte_data(client, CHIP_ID_REG) != NCT7904_ID ||
+	    (i2c_smbus_read_byte_data(client, DEVICE_ID_REG) & 0xf0) != 0x50 ||
+	    (i2c_smbus_read_byte_data(client, BANK_SEL_REG) & 0xf8) != 0x00)
+		return -ENODEV;
+
+	strlcpy(info->type, "nct7904", I2C_NAME_SIZE);
+
+	return 0;
+}
+
+static const struct hwmon_channel_info *nct7904_info[] = {
+	HWMON_CHANNEL_INFO(in,
+			   /* dummy, skipped in is_visible */
+			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
+			   HWMON_I_ALARM,
+			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
+			   HWMON_I_ALARM,
+			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
+			   HWMON_I_ALARM,
+			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
+			   HWMON_I_ALARM,
+			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
+			   HWMON_I_ALARM,
+			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
+			   HWMON_I_ALARM,
+			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
+			   HWMON_I_ALARM,
+			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
+			   HWMON_I_ALARM,
+			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
+			   HWMON_I_ALARM,
+			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
+			   HWMON_I_ALARM,
+			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
+			   HWMON_I_ALARM,
+			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
+			   HWMON_I_ALARM,
+			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
+			   HWMON_I_ALARM,
+			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
+			   HWMON_I_ALARM,
+			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
+			   HWMON_I_ALARM,
+			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
+			   HWMON_I_ALARM,
+			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
+			   HWMON_I_ALARM,
+			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
+			   HWMON_I_ALARM,
+			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
+			   HWMON_I_ALARM,
+			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
+			   HWMON_I_ALARM,
+			   HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX |
+			   HWMON_I_ALARM),
+	HWMON_CHANNEL_INFO(fan,
+			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
+			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
+			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
+			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
+			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
+			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
+			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
+			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
+			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
+			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
+			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM,
+			   HWMON_F_INPUT | HWMON_F_MIN | HWMON_F_ALARM),
+	HWMON_CHANNEL_INFO(pwm,
+			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
+			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
+			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
+			   HWMON_PWM_INPUT | HWMON_PWM_ENABLE),
+	HWMON_CHANNEL_INFO(temp,
+			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
+			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
+			   HWMON_T_CRIT_HYST,
+			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
+			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
+			   HWMON_T_CRIT_HYST,
+			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
+			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
+			   HWMON_T_CRIT_HYST,
+			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
+			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
+			   HWMON_T_CRIT_HYST,
+			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
+			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
+			   HWMON_T_CRIT_HYST,
+			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
+			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
+			   HWMON_T_CRIT_HYST,
+			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
+			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
+			   HWMON_T_CRIT_HYST,
+			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
+			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
+			   HWMON_T_CRIT_HYST,
+			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
+			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
+			   HWMON_T_CRIT_HYST,
+			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
+			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
+			   HWMON_T_CRIT_HYST,
+			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
+			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
+			   HWMON_T_CRIT_HYST,
+			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
+			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
+			   HWMON_T_CRIT_HYST,
+			   HWMON_T_INPUT | HWMON_T_ALARM | HWMON_T_MAX |
+			   HWMON_T_MAX_HYST | HWMON_T_TYPE | HWMON_T_CRIT |
+			   HWMON_T_CRIT_HYST),
+	NULL
+};
+
+static const struct hwmon_ops nct7904_hwmon_ops = {
+	.is_visible = nct7904_is_visible,
+	.read = nct7904_read,
+	.write = nct7904_write,
+};
+
+static const struct hwmon_chip_info nct7904_chip_info = {
+	.ops = &nct7904_hwmon_ops,
+	.info = nct7904_info,
+};
+
+/*
+ * Watchdog Function
+ */
+static int nct7904_wdt_start(struct watchdog_device *wdt)
+{
+	struct nct7904_data *data = watchdog_get_drvdata(wdt);
+
+	/* Enable soft watchdog timer */
+	return nct7904_write_reg(data, BANK_0, WDT_LOCK_REG, WDT_SOFT_EN);
+}
+
+static int nct7904_wdt_stop(struct watchdog_device *wdt)
+{
+	struct nct7904_data *data = watchdog_get_drvdata(wdt);
+
+	return nct7904_write_reg(data, BANK_0, WDT_LOCK_REG, WDT_SOFT_DIS);
+}
+
+static int nct7904_wdt_set_timeout(struct watchdog_device *wdt,
+				   unsigned int timeout)
+{
+	struct nct7904_data *data = watchdog_get_drvdata(wdt);
+	/*
+	 * The NCT7904 is very special in watchdog function.
+	 * Its minimum unit is minutes. And wdt->timeout needs
+	 * to match the actual timeout selected. So, this needs
+	 * to be: wdt->timeout = timeout / 60 * 60.
+	 * For example, if the user configures a timeout of
+	 * 119 seconds, the actual timeout will be 60 seconds.
+	 * So, wdt->timeout must then be set to 60 seconds.
+	 */
+	wdt->timeout = timeout / 60 * 60;
+
+	return nct7904_write_reg(data, BANK_0, WDT_TIMER_REG,
+				 wdt->timeout / 60);
+}
+
+static int nct7904_wdt_ping(struct watchdog_device *wdt)
+{
+	/*
+	 * Note:
+	 * NCT7904 does not support refreshing WDT_TIMER_REG register when
+	 * the watchdog is active. Please disable watchdog before feeding
+	 * the watchdog and enable it again.
+	 */
+	struct nct7904_data *data = watchdog_get_drvdata(wdt);
+	int ret;
+
+	/* Disable soft watchdog timer */
+	ret = nct7904_write_reg(data, BANK_0, WDT_LOCK_REG, WDT_SOFT_DIS);
+	if (ret < 0)
+		return ret;
+
+	/* feed watchdog */
+	ret = nct7904_write_reg(data, BANK_0, WDT_TIMER_REG, wdt->timeout / 60);
+	if (ret < 0)
+		return ret;
+
+	/* Enable soft watchdog timer */
+	return nct7904_write_reg(data, BANK_0, WDT_LOCK_REG, WDT_SOFT_EN);
+}
+
+static unsigned int nct7904_wdt_get_timeleft(struct watchdog_device *wdt)
+{
+	struct nct7904_data *data = watchdog_get_drvdata(wdt);
+	int ret;
+
+	ret = nct7904_read_reg(data, BANK_0, WDT_TIMER_REG);
+	if (ret < 0)
+		return 0;
+
+	return ret * 60;
+}
+
+static const struct watchdog_info nct7904_wdt_info = {
+	.options	= WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING |
+				WDIOF_MAGICCLOSE,
+	.identity	= "nct7904 watchdog",
+};
+
+static const struct watchdog_ops nct7904_wdt_ops = {
+	.owner		= THIS_MODULE,
+	.start		= nct7904_wdt_start,
+	.stop		= nct7904_wdt_stop,
+	.ping		= nct7904_wdt_ping,
+	.set_timeout	= nct7904_wdt_set_timeout,
+	.get_timeleft	= nct7904_wdt_get_timeleft,
+};
+
+static int nct7904_probe(struct i2c_client *client)
+{
+	struct nct7904_data *data;
+	struct device *hwmon_dev;
+	struct device *dev = &client->dev;
+	int ret, i;
+	u32 mask;
+	u8 val, bit;
+
+	data = devm_kzalloc(dev, sizeof(struct nct7904_data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->client = client;
+	mutex_init(&data->bank_lock);
+	data->bank_sel = -1;
+
+	/* Setup sensor groups. */
+	/* FANIN attributes */
+	ret = nct7904_read_reg16(data, BANK_0, FANIN_CTRL0_REG);
+	if (ret < 0)
+		return ret;
+	data->fanin_mask = (ret >> 8) | ((ret & 0xff) << 8);
+
+	/*
+	 * VSEN attributes
+	 *
+	 * Note: voltage sensors overlap with external temperature
+	 * sensors. So, if we ever decide to support the latter
+	 * we will have to adjust 'vsen_mask' accordingly.
+	 */
+	mask = 0;
+	ret = nct7904_read_reg16(data, BANK_0, VT_ADC_CTRL0_REG);
+	if (ret >= 0)
+		mask = (ret >> 8) | ((ret & 0xff) << 8);
+	ret = nct7904_read_reg(data, BANK_0, VT_ADC_CTRL2_REG);
+	if (ret >= 0)
+		mask |= (ret << 16);
+	data->vsen_mask = mask;
+
+	/* CPU_TEMP attributes */
+	ret = nct7904_read_reg(data, BANK_0, VT_ADC_CTRL0_REG);
+	if (ret < 0)
+		return ret;
+
+	if ((ret & 0x6) == 0x6)
+		data->tcpu_mask |= 1; /* TR1 */
+	if ((ret & 0x18) == 0x18)
+		data->tcpu_mask |= 2; /* TR2 */
+	if ((ret & 0x20) == 0x20)
+		data->tcpu_mask |= 4; /* TR3 */
+	if ((ret & 0x80) == 0x80)
+		data->tcpu_mask |= 8; /* TR4 */
+
+	/* LTD */
+	ret = nct7904_read_reg(data, BANK_0, VT_ADC_CTRL2_REG);
+	if (ret < 0)
+		return ret;
+	if ((ret & 0x02) == 0x02)
+		data->tcpu_mask |= 0x10;
+
+	/* Multi-Function detecting for Volt and TR/TD */
+	ret = nct7904_read_reg(data, BANK_0, VT_ADC_MD_REG);
+	if (ret < 0)
+		return ret;
+
+	data->temp_mode = 0;
+	for (i = 0; i < 4; i++) {
+		val = (ret >> (i * 2)) & 0x03;
+		bit = (1 << i);
+		if (val == VOLT_MONITOR_MODE) {
+			data->tcpu_mask &= ~bit;
+		} else if (val == THERMAL_DIODE_MODE && i < 2) {
+			data->temp_mode |= bit;
+			data->vsen_mask &= ~(0x06 << (i * 2));
+		} else if (val == THERMISTOR_MODE) {
+			data->vsen_mask &= ~(0x02 << (i * 2));
+		} else {
+			/* Reserved */
+			data->tcpu_mask &= ~bit;
+			data->vsen_mask &= ~(0x06 << (i * 2));
+		}
+	}
+
+	/* PECI */
+	ret = nct7904_read_reg(data, BANK_2, PFE_REG);
+	if (ret < 0)
+		return ret;
+	if (ret & 0x80) {
+		data->enable_dts = 1; /* Enable DTS & PECI */
+	} else {
+		ret = nct7904_read_reg(data, BANK_2, TSI_CTRL_REG);
+		if (ret < 0)
+			return ret;
+		if (ret & 0x80)
+			data->enable_dts = 0x3; /* Enable DTS & TSI */
+	}
+
+	/* Check DTS enable status */
+	if (data->enable_dts) {
+		ret = nct7904_read_reg(data, BANK_0, DTS_T_CTRL0_REG);
+		if (ret < 0)
+			return ret;
+		data->has_dts = ret & 0xF;
+		if (data->enable_dts & ENABLE_TSI) {
+			ret = nct7904_read_reg(data, BANK_0, DTS_T_CTRL1_REG);
+			if (ret < 0)
+				return ret;
+			data->has_dts |= (ret & 0xF) << 4;
+		}
+	}
+
+	for (i = 0; i < FANCTL_MAX; i++) {
+		ret = nct7904_read_reg(data, BANK_3, FANCTL1_FMR_REG + i);
+		if (ret < 0)
+			return ret;
+		data->fan_mode[i] = ret;
+	}
+
+	/* Read all of SMI status register to clear alarms */
+	for (i = 0; i < SMI_STS_MAX; i++) {
+		ret = nct7904_read_reg(data, BANK_0, SMI_STS1_REG + i);
+		if (ret < 0)
+			return ret;
+	}
+
+	hwmon_dev =
+		devm_hwmon_device_register_with_info(dev, client->name, data,
+						     &nct7904_chip_info, NULL);
+	ret = PTR_ERR_OR_ZERO(hwmon_dev);
+	if (ret)
+		return ret;
+
+	/* Watchdog initialization */
+	data->wdt.ops = &nct7904_wdt_ops;
+	data->wdt.info = &nct7904_wdt_info;
+
+	data->wdt.timeout = WATCHDOG_TIMEOUT * 60; /* Set default timeout */
+	data->wdt.min_timeout = MIN_TIMEOUT;
+	data->wdt.max_timeout = MAX_TIMEOUT;
+	data->wdt.parent = &client->dev;
+
+	watchdog_init_timeout(&data->wdt, timeout * 60, &client->dev);
+	watchdog_set_nowayout(&data->wdt, nowayout);
+	watchdog_set_drvdata(&data->wdt, data);
+
+	watchdog_stop_on_unregister(&data->wdt);
+
+	return devm_watchdog_register_device(dev, &data->wdt);
+}
+
+static const struct i2c_device_id nct7904_id[] = {
+	{"nct7904", 0},
+	{}
+};
+MODULE_DEVICE_TABLE(i2c, nct7904_id);
+
+static struct i2c_driver nct7904_driver = {
+	.class = I2C_CLASS_HWMON,
+	.driver = {
+		.name = "nct7904",
+	},
+	.probe_new = nct7904_probe,
+	.id_table = nct7904_id,
+	.detect = nct7904_detect,
+	.address_list = normal_i2c,
+};
+
+module_i2c_driver(nct7904_driver);
+
+MODULE_AUTHOR("Vadim V. Vlasov <vvlasov@dev.rtsoft.ru>");
+MODULE_DESCRIPTION("Hwmon driver for NUVOTON NCT7904");
+MODULE_LICENSE("GPL");