* [PATCH 2/3] hwmon: (nct6775) Add support for NCT6126D
2026-09-09 18:25 [PATCH 0/3] hwmon: (nct6775) Add support for NCT6122D and NCT6126D Paul Louvel
2026-09-09 18:25 ` [PATCH 1/3] Documentation: hwmon: (nct6775) Document NCT6116D/NCT6122D/NCT6126D support Paul Louvel
@ 2026-09-09 18:25 ` Paul Louvel
2026-09-09 20:28 ` Guenter Roeck
2026-09-09 18:25 ` [PATCH 3/3] hwmon: (nct6775) Add support for NCT6122D Paul Louvel
2 siblings, 1 reply; 7+ messages in thread
From: Paul Louvel @ 2026-09-09 18:25 UTC (permalink / raw)
To: Guenter Roeck, Jonathan Corbet, Shuah Khan, Randy Dunlap
Cc: Thomas Petazzoni, linux-hwmon, linux-doc, linux-kernel,
Paul Louvel
Add support for the hardware monitoring functionality of the NCT6126D
Super-I/O chip.
The NCT6126D hardware monitor is nearly identical to the NCT6116D: the
fan, PWM, temperature, TSI, alarm.
The differences are:
- Device IDs 0xd283 (A version) and 0xd284 (B version), which both fall
into the NCT6116D ID range (0xd280) when masked with SIO_ID_MASK.
Instead, compare the full value to distinguish from NCT6116D.
- One additional VIN: VHIF scaled at 16 mV/LSB.
- The fan count limit registers are documented for all five fans.
Also expose fan4_min.
Assisted-by: opencode:z-ai/glm-5.3-flash
Signed-Off: Paul Louvel <paul.louvel@bootlin.com>
---
drivers/hwmon/nct6775-core.c | 116 +++++++++++++++++++++++++++++++++++++++
drivers/hwmon/nct6775-platform.c | 29 +++++++++-
drivers/hwmon/nct6775.h | 4 +-
3 files changed, 146 insertions(+), 3 deletions(-)
diff --git a/drivers/hwmon/nct6775-core.c b/drivers/hwmon/nct6775-core.c
index 759ea3d1286e..cf27b9c7a89e 100644
--- a/drivers/hwmon/nct6775-core.c
+++ b/drivers/hwmon/nct6775-core.c
@@ -21,6 +21,8 @@
* Chip #vin #fan #pwm #temp chip IDs man ID
* nct6106d 9 3 3 6+3 0xc450 0xc1 0x5ca3
* nct6116d 9 5 5 3+3 0xd280 0xc1 0x5ca3
+ * nct6126d 10 5 5 3+3 0xd283 0xc1 0x5ca3
+ * (0xd284)
* nct6775f 9 4 3 6+3 0xb470 0xc1 0x5ca3
* nct6776f 9 5 3 6+3 0xc330 0xc1 0x5ca3
* nct6779d 15 5 5 2+6 0xc560 0xc1 0x5ca3
@@ -66,6 +68,7 @@
static const char * const nct6775_device_names[] = {
[nct6106] = "nct6106",
[nct6116] = "nct6116",
+ [nct6126] = "nct6126",
[nct6775] = "nct6775",
[nct6776] = "nct6776",
[nct6779] = "nct6779",
@@ -897,6 +900,31 @@ static const s8 NCT6116_BEEP_BITS[NUM_BEEP_BITS] = {
static const u16 NCT6116_REG_TSI_TEMP[] = { 0x59, 0x5b };
+/* NCT6122D/NCT6126D specific data */
+
+static const u16 NCT6126_REG_IN[] = {
+ 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09 };
+static const u16 NCT6126_REG_IN_MAX[] = {
+ 0x90, 0x92, 0x94, 0x96, 0x98, 0x9a, 0x9c, 0x9e, 0xa0, 0xa2 };
+static const u16 NCT6126_REG_IN_MIN[] = {
+ 0x91, 0x93, 0x95, 0x97, 0x99, 0x9b, 0x9d, 0x9f, 0xa1, 0xa3 };
+
+static const s8 NCT6126_ALARM_BITS[NUM_ALARM_BITS] = {
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, -1, -1, /* in0-in11 */
+ -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* in12-in23 */
+ 32, 33, 34, 35, 36, -1, -1, -1, -1, -1, -1, -1, /* fan1-fan12 */
+ 16, 17, 18, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* temp1-temp12 */
+ 48, -1, /* intr0-intr1 */
+};
+
+static const s8 NCT6126_BEEP_BITS[NUM_BEEP_BITS] = {
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, /* in0-in11 */
+ -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* in12-in23 */
+ 24, 25, 26, 27, 28, -1, -1, -1, -1, -1, -1, -1, /* fan1-fan12 */
+ 16, 17, 18, -1, -1, -1, -1, -1, -1, -1, -1, -1, /* temp1-temp12 */
+ 34, -1, 32 /* intr0-intr1, beep_en */
+};
+
static enum pwm_enable reg_to_pwm_enable(int pwm, int mode)
{
if (mode == 0 && pwm == 255)
@@ -998,6 +1026,14 @@ static const u16 scale_in_6798[NUM_IN] = {
800, 800, 800, 1600, 800
};
+/*
+ * NCT6126 scaling:
+ * CPUVCORE, VIN0, AVSB, 3VCC, VIN1, VIN2, VHIF, 3VSB, VBAT, VTT
+ */
+static const u16 scale_in_6126[10] = {
+ 800, 800, 1600, 1600, 800, 800, 1600, 1600, 1600, 800
+};
+
static inline long in_from_reg(u8 reg, u8 nr, const u16 *scales)
{
return DIV_ROUND_CLOSEST(reg * scales[nr], 100);
@@ -1156,6 +1192,7 @@ bool nct6775_reg_is_word_sized(struct nct6775_data *data, u16 reg)
reg == 0xe0 || reg == 0xe2 || reg == 0xe4 ||
reg == 0x111 || reg == 0x121 || reg == 0x131;
case nct6116:
+ case nct6126:
return reg == 0x20 || reg == 0x22 || reg == 0x24 ||
reg == 0x26 || reg == 0x28 || reg == 0x59 || reg == 0x5b ||
reg == 0xe0 || reg == 0xe2 || reg == 0xe4 || reg == 0xe6 ||
@@ -1538,6 +1575,7 @@ static int nct6775_update_pwm_limits(struct device *dev)
break;
case nct6106:
case nct6116:
+ case nct6126:
case nct6779:
case nct6791:
case nct6792:
@@ -3203,6 +3241,7 @@ store_auto_pwm(struct device *dev, struct device_attribute *attr,
break; /* always enabled, nothing to do */
case nct6106:
case nct6116:
+ case nct6126:
case nct6779:
case nct6791:
case nct6792:
@@ -3677,6 +3716,83 @@ int nct6775_probe(struct device *dev, struct nct6775_data *data,
reg_temp_crit_l = NCT6106_REG_TEMP_CRIT_L;
reg_temp_crit_h = NCT6106_REG_TEMP_CRIT_H;
+ break;
+ case nct6126:
+ data->in_num = 10;
+ data->scale_in = scale_in_6126;
+ data->pwm_num = 5;
+ data->auto_pwm_num = 4;
+ data->temp_fixed_num = 3;
+ data->num_temp_alarms = 3;
+ data->num_temp_beeps = 3;
+
+ data->fan_from_reg = fan_from_reg13;
+ data->fan_from_reg_min = fan_from_reg13;
+
+ data->temp_label = nct6776_temp_label;
+ data->temp_mask = NCT6776_TEMP_MASK;
+ data->virt_temp_mask = NCT6776_VIRT_TEMP_MASK;
+
+ data->REG_VBAT = NCT6106_REG_VBAT;
+ data->REG_DIODE = NCT6106_REG_DIODE;
+ data->DIODE_MASK = NCT6106_DIODE_MASK;
+ data->REG_VIN = NCT6126_REG_IN;
+ data->REG_IN_MINMAX[0] = NCT6126_REG_IN_MIN;
+ data->REG_IN_MINMAX[1] = NCT6126_REG_IN_MAX;
+ data->REG_TARGET = NCT6116_REG_TARGET;
+ data->REG_FAN = NCT6116_REG_FAN;
+ data->REG_FAN_MODE = NCT6116_REG_FAN_MODE;
+ data->REG_FAN_MIN = NCT6116_REG_FAN_MIN;
+ data->REG_FAN_PULSES = NCT6116_REG_FAN_PULSES;
+ data->FAN_PULSE_SHIFT = NCT6116_FAN_PULSE_SHIFT;
+ data->REG_FAN_TIME[0] = NCT6116_REG_FAN_STOP_TIME;
+ data->REG_FAN_TIME[1] = NCT6116_REG_FAN_STEP_UP_TIME;
+ data->REG_FAN_TIME[2] = NCT6116_REG_FAN_STEP_DOWN_TIME;
+ data->REG_TOLERANCE_H = NCT6116_REG_TOLERANCE_H;
+ data->REG_PWM[0] = NCT6116_REG_PWM;
+ data->REG_PWM[1] = NCT6116_REG_FAN_START_OUTPUT;
+ data->REG_PWM[2] = NCT6116_REG_FAN_STOP_OUTPUT;
+ data->REG_PWM[5] = NCT6106_REG_WEIGHT_DUTY_STEP;
+ data->REG_PWM[6] = NCT6106_REG_WEIGHT_DUTY_BASE;
+ data->REG_PWM_READ = NCT6106_REG_PWM_READ;
+ data->REG_PWM_MODE = NCT6106_REG_PWM_MODE;
+ data->PWM_MODE_MASK = NCT6106_PWM_MODE_MASK;
+ data->REG_AUTO_TEMP = NCT6116_REG_AUTO_TEMP;
+ data->REG_AUTO_PWM = NCT6116_REG_AUTO_PWM;
+ data->REG_CRITICAL_TEMP = NCT6116_REG_CRITICAL_TEMP;
+ data->REG_CRITICAL_TEMP_TOLERANCE =
+ NCT6116_REG_CRITICAL_TEMP_TOLERANCE;
+ data->REG_CRITICAL_PWM_ENABLE = NCT6116_REG_CRITICAL_PWM_ENABLE;
+ data->CRITICAL_PWM_ENABLE_MASK =
+ NCT6106_CRITICAL_PWM_ENABLE_MASK;
+ data->REG_CRITICAL_PWM = NCT6116_REG_CRITICAL_PWM;
+ data->REG_TEMP_OFFSET = NCT6106_REG_TEMP_OFFSET;
+ data->REG_TEMP_SOURCE = NCT6106_REG_TEMP_SOURCE;
+ data->REG_TEMP_SEL = NCT6116_REG_TEMP_SEL;
+ data->REG_WEIGHT_TEMP_SEL = NCT6106_REG_WEIGHT_TEMP_SEL;
+ data->REG_WEIGHT_TEMP[0] = NCT6106_REG_WEIGHT_TEMP_STEP;
+ data->REG_WEIGHT_TEMP[1] = NCT6106_REG_WEIGHT_TEMP_STEP_TOL;
+ data->REG_WEIGHT_TEMP[2] = NCT6106_REG_WEIGHT_TEMP_BASE;
+ data->REG_ALARM = NCT6106_REG_ALARM;
+ data->ALARM_BITS = NCT6126_ALARM_BITS;
+ data->REG_BEEP = NCT6106_REG_BEEP;
+ data->BEEP_BITS = NCT6126_BEEP_BITS;
+ data->REG_TSI_TEMP = NCT6116_REG_TSI_TEMP;
+
+ reg_temp = NCT6106_REG_TEMP;
+ reg_temp_mon = NCT6106_REG_TEMP_MON;
+ num_reg_temp = 3;
+ num_reg_temp_mon = ARRAY_SIZE(NCT6106_REG_TEMP_MON);
+ num_reg_tsi_temp = ARRAY_SIZE(NCT6116_REG_TSI_TEMP);
+ reg_temp_over = NCT6106_REG_TEMP_OVER;
+ reg_temp_hyst = NCT6106_REG_TEMP_HYST;
+ reg_temp_config = NCT6106_REG_TEMP_CONFIG;
+ num_reg_temp_config = 3;
+ reg_temp_alternate = NCT6106_REG_TEMP_ALTERNATE;
+ reg_temp_crit = NCT6106_REG_TEMP_CRIT;
+ reg_temp_crit_l = NCT6106_REG_TEMP_CRIT_L;
+ reg_temp_crit_h = NCT6106_REG_TEMP_CRIT_H;
+
break;
case nct6775:
data->in_num = 9;
diff --git a/drivers/hwmon/nct6775-platform.c b/drivers/hwmon/nct6775-platform.c
index d394376e4306..a8ef58d3a883 100644
--- a/drivers/hwmon/nct6775-platform.c
+++ b/drivers/hwmon/nct6775-platform.c
@@ -25,6 +25,7 @@ enum sensor_access { access_direct, access_asuswmi };
static const char * const nct6775_sio_names[] __initconst = {
[nct6106] = "NCT6106D",
[nct6116] = "NCT6116D",
+ [nct6126] = "NCT6126D",
[nct6775] = "NCT6775F",
[nct6776] = "NCT6776D/F",
[nct6779] = "NCT6779D",
@@ -76,6 +77,8 @@ MODULE_PARM_DESC(fan_debounce, "Enable debouncing for fan RPM signal");
#define SIO_NCT6106_ID 0xc450
#define SIO_NCT6116_ID 0xd280
+#define SIO_NCT6126_A_ID 0xd283
+#define SIO_NCT6126_B_ID 0xd284
#define SIO_NCT6775_ID 0xb470
#define SIO_NCT6776_ID 0xc330
#define SIO_NCT6779_ID 0xc560
@@ -565,6 +568,25 @@ nct6775_check_fan_inputs(struct nct6775_data *data, struct nct6775_sio_data *sio
pwm3pin = fan3pin && (cr24 & 0x08);
pwm4pin = fan4pin;
pwm5pin = fan5pin;
+ } else if (data->kind == nct6126) {
+ int cr1a = sio_data->sio_inb(sio_data, 0x1a);
+ int cr1b = sio_data->sio_inb(sio_data, 0x1b);
+ int cr24 = sio_data->sio_inb(sio_data, 0x24);
+ int cr2a = sio_data->sio_inb(sio_data, 0x2a);
+ int cr2b = sio_data->sio_inb(sio_data, 0x2b);
+ int cr2f = sio_data->sio_inb(sio_data, 0x2f);
+
+ fan3pin = !(cr2b & 0x10);
+ fan4pin = (cr2b & 0x80) || /* pin 1(2) */
+ (!(cr2f & 0x10) && (cr1a & 0x04)); /* pin 65(66) */
+ fan5pin = (cr2b & 0x80) || /* pin 126(127) */
+ (!(cr1b & 0x03) && (cr2a & 0x02)); /* pin 94(96) */
+
+ pwm3pin = fan3pin && (cr24 & 0x08);
+ pwm4pin = fan4pin;
+ pwm5pin = fan5pin;
+
+ fan4min = fan4pin;
} else {
/*
* NCT6779D, NCT6791D, NCT6792D, NCT6793D, NCT6795D, NCT6796D,
@@ -861,6 +883,7 @@ static int nct6775_platform_probe_init(struct nct6775_data *data)
break;
case nct6106:
case nct6116:
+ case nct6126:
case nct6779:
case nct6791:
case nct6792:
@@ -892,6 +915,7 @@ static int nct6775_platform_probe_init(struct nct6775_data *data)
switch (data->kind) {
case nct6106:
case nct6116:
+ case nct6126:
tmp |= 0xe0;
break;
case nct6775:
@@ -1006,7 +1030,10 @@ static int __init nct6775_find(int sioaddr, struct nct6775_sio_data *sio_data)
sio_data->kind = nct6106;
break;
case SIO_NCT6116_ID:
- sio_data->kind = nct6116;
+ if (val == SIO_NCT6126_A_ID || val == SIO_NCT6126_B_ID)
+ sio_data->kind = nct6126;
+ else
+ sio_data->kind = nct6116;
break;
case SIO_NCT6775_ID:
sio_data->kind = nct6775;
diff --git a/drivers/hwmon/nct6775.h b/drivers/hwmon/nct6775.h
index 296eff99d003..d18ac91be497 100644
--- a/drivers/hwmon/nct6775.h
+++ b/drivers/hwmon/nct6775.h
@@ -4,8 +4,8 @@
#include <linux/types.h>
-enum kinds { nct6106, nct6116, nct6775, nct6776, nct6779, nct6791, nct6792,
- nct6793, nct6795, nct6796, nct6797, nct6798, nct6799 };
+enum kinds { nct6106, nct6116, nct6126, nct6775, nct6776, nct6779, nct6791,
+ nct6792, nct6793, nct6795, nct6796, nct6797, nct6798, nct6799 };
enum pwm_enable { off, manual, thermal_cruise, speed_cruise, sf3, sf4 };
#define NUM_TEMP 12 /* Max number of temp attribute sets w/ limits*/
--
2.55.0
^ permalink raw reply related [flat|nested] 7+ messages in thread