hwmon: add MP2869,MP29608,MP29612 and MP29816 series driver
authorWensheng Wang <wenswang@yeah.net>
Tue, 5 Aug 2025 10:20:19 +0000 (18:20 +0800)
committerGuenter Roeck <linux@roeck-us.net>
Sun, 7 Sep 2025 23:35:18 +0000 (16:35 -0700)
Add support for MPS VR mp2869/mp2869a,mp29608/mp29608a,mp29612/mp29612a
and mp29816/mp29816a/mp29816b/mp29816c controller. This driver exposes
telemetry and limit value readings and writtings.

Signed-off-by: Wensheng Wang <wenswang@yeah.net>
Link: https://lore.kernel.org/r/20250805102020.749850-2-wenswang@yeah.net
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Documentation/hwmon/index.rst
Documentation/hwmon/mp2869.rst [new file with mode: 0644]
MAINTAINERS
drivers/hwmon/pmbus/Kconfig
drivers/hwmon/pmbus/Makefile
drivers/hwmon/pmbus/mp2869.c [new file with mode: 0644]

index d292a86..3630314 100644 (file)
@@ -173,6 +173,7 @@ Hardware Monitoring Kernel Drivers
    menf21bmc
    mlxreg-fan
    mp2856
+   mp2869
    mp2888
    mp2891
    mp2975
diff --git a/Documentation/hwmon/mp2869.rst b/Documentation/hwmon/mp2869.rst
new file mode 100644 (file)
index 0000000..2d9d65f
--- /dev/null
@@ -0,0 +1,175 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+Kernel driver mp2869
+====================
+
+Supported chips:
+
+  * MPS mp2869
+
+    Prefix: 'mp2869'
+
+  * MPS mp29608
+
+    Prefix: 'mp29608'
+
+  * MPS mp29612
+
+    Prefix: 'mp29612'
+
+  * MPS mp29816
+
+    Prefix: 'mp29816'
+
+Author:
+
+       Wensheng Wang <wenswang@yeah.net>
+
+Description
+-----------
+
+This driver implements support for Monolithic Power Systems, Inc. (MPS)
+MP2869 Dual Loop Digital Multi-phase Controller.
+
+Device compliant with:
+
+- PMBus rev 1.3 interface.
+
+The driver exports the following attributes via the 'sysfs' files
+for input voltage:
+
+**in1_input**
+
+**in1_label**
+
+**in1_crit**
+
+**in1_crit_alarm**
+
+**in1_lcrit**
+
+**in1_lcrit_alarm**
+
+**in1_min**
+
+**in1_min_alarm**
+
+The driver provides the following attributes for output voltage:
+
+**in2_input**
+
+**in2_label**
+
+**in2_crit**
+
+**in2_crit_alarm**
+
+**in2_lcrit**
+
+**in2_lcrit_alarm**
+
+**in3_input**
+
+**in3_label**
+
+**in3_crit**
+
+**in3_crit_alarm**
+
+**in3_lcrit**
+
+**in3_lcrit_alarm**
+
+The driver provides the following attributes for input current:
+
+**curr1_input**
+
+**curr1_label**
+
+**curr2_input**
+
+**curr2_label**
+
+The driver provides the following attributes for output current:
+
+**curr3_input**
+
+**curr3_label**
+
+**curr3_crit**
+
+**curr3_crit_alarm**
+
+**curr3_max**
+
+**curr3_max_alarm**
+
+**curr4_input**
+
+**curr4_label**
+
+**curr4_crit**
+
+**curr4_crit_alarm**
+
+**curr4_max**
+
+**curr4_max_alarm**
+
+The driver provides the following attributes for input power:
+
+**power1_input**
+
+**power1_label**
+
+**power2_input**
+
+**power2_label**
+
+The driver provides the following attributes for output power:
+
+**power3_input**
+
+**power3_label**
+
+**power3_input**
+
+**power3_label**
+
+**power3_max**
+
+**power3_max_alarm**
+
+**power4_input**
+
+**power4_label**
+
+**power4_input**
+
+**power4_label**
+
+**power4_max**
+
+**power4_max_alarm**
+
+The driver provides the following attributes for temperature:
+
+**temp1_input**
+
+**temp1_crit**
+
+**temp1_crit_alarm**
+
+**temp1_max**
+
+**temp1_max_alarm**
+
+**temp2_input**
+
+**temp2_crit**
+
+**temp2_crit_alarm**
+
+**temp2_max**
+
+**temp2_max_alarm**
index b392d34..2f99cd9 100644 (file)
@@ -17175,6 +17175,13 @@ S:     Maintained
 F:     Documentation/devicetree/bindings/leds/backlight/mps,mp3309c.yaml
 F:     drivers/video/backlight/mp3309c.c
 
+MPS MP2869 DRIVER
+M:     Wensheng Wang <wenswang@yeah.net>
+L:     linux-hwmon@vger.kernel.org
+S:     Maintained
+F:     Documentation/hwmon/mp2869.rst
+F:     drivers/hwmon/pmbus/mp2869.c
+
 MPS MP2891 DRIVER
 M:     Noah Wang <noahwang.wang@outlook.com>
 L:     linux-hwmon@vger.kernel.org
index 77add0c..c5b2c5e 100644 (file)
@@ -374,6 +374,15 @@ config SENSORS_MP2856
          This driver can also be built as a module. If so, the module will
          be called mp2856.
 
+config SENSORS_MP2869
+       tristate "MPS MP2869"
+       help
+         If you say yes here you get hardware monitoring support for MPS
+         MP2869 Dual Loop Digital Multi-Phase Controller.
+
+         This driver can also be built as a module. If so, the module will
+         be called mp2869.
+
 config SENSORS_MP2888
        tristate "MPS MP2888"
        help
index 29cd8a3..6177047 100644 (file)
@@ -37,6 +37,7 @@ obj-$(CONFIG_SENSORS_MAX31785)        += max31785.o
 obj-$(CONFIG_SENSORS_MAX34440) += max34440.o
 obj-$(CONFIG_SENSORS_MAX8688)  += max8688.o
 obj-$(CONFIG_SENSORS_MP2856)   += mp2856.o
+obj-$(CONFIG_SENSORS_MP2869)   += mp2869.o
 obj-$(CONFIG_SENSORS_MP2888)   += mp2888.o
 obj-$(CONFIG_SENSORS_MP2891)   += mp2891.o
 obj-$(CONFIG_SENSORS_MP2975)   += mp2975.o
diff --git a/drivers/hwmon/pmbus/mp2869.c b/drivers/hwmon/pmbus/mp2869.c
new file mode 100644 (file)
index 0000000..cc69a1e
--- /dev/null
@@ -0,0 +1,659 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Hardware monitoring driver for MPS Multi-phase Digital VR Controllers(MP2869)
+ */
+
+#include <linux/bitfield.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include "pmbus.h"
+
+/*
+ * Vender specific registers, the register MFR_SVI3_IOUT_PRT(0x67),
+ * READ_PIN_EST(0x94)and READ_IIN_EST(0x95) redefine the standard
+ * PMBUS register. The MFR_VOUT_LOOP_CTRL(0x29) is used to identify
+ * the vout scale and the MFR_SVI3_IOUT_PRT(0x67) is used to identify
+ * the iout scale. The READ_PIN_EST(0x94) is used to read input power
+ * per rail. The MP2891 does not have standard READ_IIN register(0x89),
+ * the iin telemetry can be obtained through the vendor redefined
+ * register READ_IIN_EST(0x95).
+ */
+#define MFR_SVI3_IOUT_PRT      0x67
+#define MFR_READ_PIN_EST       0x94
+#define MFR_READ_IIN_EST       0x95
+#define MFR_TSNS_FLT_SET       0xBB
+
+#define MP2869_VIN_OV_FAULT_GAIN       4
+#define MP2869_READ_VOUT_DIV   1024
+#define MP2869_READ_IOUT_DIV   32
+#define MP2869_OVUV_LIMIT_SCALE        10
+#define MP2869_OVUV_DELTA_SCALE        50
+#define MP2869_TEMP_LIMIT_OFFSET       40
+#define MP2869_IOUT_LIMIT_UINT 8
+#define MP2869_POUT_OP_GAIN    2
+
+#define MP2869_PAGE_NUM        2
+
+#define MP2869_RAIL1_FUNC      (PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | \
+                                                       PMBUS_HAVE_IOUT | PMBUS_HAVE_POUT | \
+                                                       PMBUS_HAVE_TEMP | PMBUS_HAVE_PIN | \
+                                                       PMBUS_HAVE_IIN | \
+                                                       PMBUS_HAVE_STATUS_VOUT | \
+                                                       PMBUS_HAVE_STATUS_IOUT | \
+                                                       PMBUS_HAVE_STATUS_TEMP | \
+                                                       PMBUS_HAVE_STATUS_INPUT)
+
+#define MP2869_RAIL2_FUNC      (PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT | \
+                                                        PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP | \
+                                                        PMBUS_HAVE_PIN | PMBUS_HAVE_IIN | \
+                                                        PMBUS_HAVE_STATUS_VOUT | \
+                                                        PMBUS_HAVE_STATUS_IOUT | \
+                                                        PMBUS_HAVE_STATUS_TEMP | \
+                                                        PMBUS_HAVE_STATUS_INPUT)
+
+struct mp2869_data {
+       struct pmbus_driver_info info;
+       bool mfr_thwn_flt_en;
+       int vout_scale[MP2869_PAGE_NUM];
+       int iout_scale[MP2869_PAGE_NUM];
+};
+
+static const int mp2869_vout_sacle[8] = {6400, 5120, 2560, 2048, 1024,
+                                                                                4, 2, 1};
+static const int mp2869_iout_sacle[8] = {32, 1, 2, 4, 8, 16, 32, 64};
+
+#define to_mp2869_data(x)      container_of(x, struct mp2869_data, info)
+
+static u16 mp2869_reg2data_linear11(u16 word)
+{
+       s16 exponent;
+       s32 mantissa;
+       s64 val;
+
+       exponent = ((s16)word) >> 11;
+       mantissa = ((s16)((word & 0x7ff) << 5)) >> 5;
+       val = mantissa;
+
+       if (exponent >= 0)
+               val <<= exponent;
+       else
+               val >>= -exponent;
+
+       return val;
+}
+
+static int
+mp2869_identify_thwn_flt(struct i2c_client *client, struct pmbus_driver_info *info,
+                        int page)
+{
+       struct mp2869_data *data = to_mp2869_data(info);
+       int ret;
+
+       ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, page);
+       if (ret < 0)
+               return ret;
+
+       ret = i2c_smbus_read_word_data(client, MFR_TSNS_FLT_SET);
+       if (ret < 0)
+               return ret;
+
+       data->mfr_thwn_flt_en = FIELD_GET(GENMASK(13, 13), ret);
+
+       return 0;
+}
+
+static int
+mp2869_identify_vout_scale(struct i2c_client *client, struct pmbus_driver_info *info,
+                          int page)
+{
+       struct mp2869_data *data = to_mp2869_data(info);
+       int ret;
+
+       ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, page);
+       if (ret < 0)
+               return ret;
+
+       ret = i2c_smbus_read_word_data(client, PMBUS_VOUT_SCALE_LOOP);
+       if (ret < 0)
+               return ret;
+
+       /*
+        * The output voltage is equal to the READ_VOUT(0x8B) register value multiply
+        * by vout_scale.
+        * Obtain vout scale from the register PMBUS_VOUT_SCALE_LOOP, bits 12-10
+        * PMBUS_VOUT_SCALE_LOOP[12:10]:
+        * 000b - 6.25mV/LSB, 001b - 5mV/LSB, 010b - 2.5mV/LSB, 011b - 2mV/LSB
+        * 100b - 1mV/Lsb, 101b - (1/256)mV/LSB, 110b - (1/512)mV/LSB,
+        * 111b - (1/1024)mV/LSB
+        */
+       data->vout_scale[page] = mp2869_vout_sacle[FIELD_GET(GENMASK(12, 10), ret)];
+
+       return 0;
+}
+
+static int
+mp2869_identify_iout_scale(struct i2c_client *client, struct pmbus_driver_info *info,
+                          int page)
+{
+       struct mp2869_data *data = to_mp2869_data(info);
+       int ret;
+
+       ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, page);
+       if (ret < 0)
+               return ret;
+
+       ret = i2c_smbus_read_word_data(client, MFR_SVI3_IOUT_PRT);
+       if (ret < 0)
+               return ret;
+
+       /*
+        * The output current is equal to the READ_IOUT(0x8C) register value
+        * multiply by iout_scale.
+        * Obtain iout_scale from the register MFR_SVI3_IOUT_PRT[2:0].
+        * The value is selected as below:
+        * 000b - 1A/LSB, 001b - (1/32)A/LSB, 010b - (1/16)A/LSB,
+        * 011b - (1/8)A/LSB, 100b - (1/4)A/LSB, 101b - (1/2)A/LSB
+        * 110b - 1A/LSB, 111b - 2A/LSB
+        */
+       data->iout_scale[page] = mp2869_iout_sacle[FIELD_GET(GENMASK(2, 0), ret)];
+
+       return 0;
+}
+
+static int mp2869_read_byte_data(struct i2c_client *client, int page, int reg)
+{
+       const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
+       struct mp2869_data *data = to_mp2869_data(info);
+       int ret;
+
+       switch (reg) {
+       case PMBUS_VOUT_MODE:
+               /*
+                * The calculation of vout in this driver is based on direct format.
+                * As a result, the format of vout is enforced to direct.
+                */
+               ret = PB_VOUT_MODE_DIRECT;
+               break;
+       case PMBUS_STATUS_BYTE:
+               /*
+                * If the tsns digital fault is enabled, the TEMPERATURE flag
+                * of PMBUS_STATUS_BYTE should come from STATUS_MFR_SPECIFIC
+                * register bit1.
+                */
+               if (!data->mfr_thwn_flt_en)
+                       return -ENODATA;
+
+               ret = pmbus_read_byte_data(client, page, reg);
+               if (ret < 0)
+                       return ret;
+
+               ret = (ret & ~GENMASK(2, 2)) |
+                       FIELD_PREP(GENMASK(2, 2),
+                                  FIELD_GET(GENMASK(1, 1),
+                                            pmbus_read_byte_data(client, page,
+                                                                 PMBUS_STATUS_MFR_SPECIFIC)));
+               break;
+       case PMBUS_STATUS_TEMPERATURE:
+               /*
+                * If the tsns digital fault is enabled, the OT Fault and OT Warning
+                * flag of PMBUS_STATUS_TEMPERATURE should come from STATUS_MFR_SPECIFIC
+                * register bit1.
+                */
+               if (!data->mfr_thwn_flt_en)
+                       return -ENODATA;
+
+               ret = pmbus_read_byte_data(client, page, reg);
+               if (ret < 0)
+                       return ret;
+
+               ret = (ret & ~GENMASK(7, 6)) |
+                       FIELD_PREP(GENMASK(6, 6),
+                                  FIELD_GET(GENMASK(1, 1),
+                                            pmbus_read_byte_data(client, page,
+                                                                 PMBUS_STATUS_MFR_SPECIFIC))) |
+                        FIELD_PREP(GENMASK(7, 7),
+                                   FIELD_GET(GENMASK(1, 1),
+                                             pmbus_read_byte_data(client, page,
+                                                                  PMBUS_STATUS_MFR_SPECIFIC)));
+               break;
+       default:
+               ret = -ENODATA;
+               break;
+       }
+
+       return ret;
+}
+
+static int mp2869_read_word_data(struct i2c_client *client, int page, int phase,
+                                int reg)
+{
+       const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
+       struct mp2869_data *data = to_mp2869_data(info);
+       int ret;
+
+       switch (reg) {
+       case PMBUS_STATUS_WORD:
+               /*
+                * If the tsns digital fault is enabled, the OT Fault flag
+                * of PMBUS_STATUS_WORD should come from STATUS_MFR_SPECIFIC
+                * register bit1.
+                */
+               if (!data->mfr_thwn_flt_en)
+                       return -ENODATA;
+
+               ret = pmbus_read_word_data(client, page, phase, reg);
+               if (ret < 0)
+                       return ret;
+
+               ret = (ret & ~GENMASK(2, 2)) |
+                        FIELD_PREP(GENMASK(2, 2),
+                                   FIELD_GET(GENMASK(1, 1),
+                                             pmbus_read_byte_data(client, page,
+                                                                  PMBUS_STATUS_MFR_SPECIFIC)));
+               break;
+       case PMBUS_READ_VIN:
+               /*
+                * The MP2869 PMBUS_READ_VIN[10:0] is the vin value, the vin scale is
+                * 31.25mV/LSB. And the vin scale is set to 31.25mV/Lsb(using r/m/b scale)
+                * in MP2869 pmbus_driver_info struct, so the word data bit0-bit10 can be
+                * returned to pmbus core directly.
+                */
+               ret = pmbus_read_word_data(client, page, phase, reg);
+               if (ret < 0)
+                       return ret;
+
+               ret = FIELD_GET(GENMASK(10, 0), ret);
+               break;
+       case PMBUS_READ_IIN:
+               /*
+                * The MP2869 redefine the standard 0x95 register as iin telemetry
+                * per rail.
+                */
+               ret = pmbus_read_word_data(client, page, phase, MFR_READ_IIN_EST);
+               if (ret < 0)
+                       return ret;
+
+               break;
+       case PMBUS_READ_PIN:
+               /*
+                * The MP2869 redefine the standard 0x94 register as pin telemetry
+                * per rail. The MP2869 MFR_READ_PIN_EST register is linear11 format,
+                * but the pin scale is set to 1W/Lsb(using r/m/b scale). As a result,
+                * the pin read from MP2869 should be converted to W, then return
+                * the result to pmbus core.
+                */
+               ret = pmbus_read_word_data(client, page, phase, MFR_READ_PIN_EST);
+               if (ret < 0)
+                       return ret;
+
+               ret = mp2869_reg2data_linear11(ret);
+               break;
+       case PMBUS_READ_VOUT:
+               ret = pmbus_read_word_data(client, page, phase, reg);
+               if (ret < 0)
+                       return ret;
+
+               ret = DIV_ROUND_CLOSEST((ret &  GENMASK(11, 0)) * data->vout_scale[page],
+                                       MP2869_READ_VOUT_DIV);
+               break;
+       case PMBUS_READ_IOUT:
+               ret = pmbus_read_word_data(client, page, phase, reg);
+               if (ret < 0)
+                       return ret;
+
+               ret = DIV_ROUND_CLOSEST((ret & GENMASK(10, 0)) * data->iout_scale[page],
+                                       MP2869_READ_IOUT_DIV);
+               break;
+       case PMBUS_READ_POUT:
+               /*
+                * The MP2869 PMBUS_READ_POUT register is linear11 format, but the pout
+                * scale is set to 1W/Lsb(using r/m/b scale). As a result, the pout read
+                * from MP2869 should be converted to W, then return the result to pmbus
+                * core.
+                */
+               ret = pmbus_read_word_data(client, page, phase, reg);
+               if (ret < 0)
+                       return ret;
+
+               ret = mp2869_reg2data_linear11(ret);
+               break;
+       case PMBUS_READ_TEMPERATURE_1:
+               ret = pmbus_read_word_data(client, page, phase, reg);
+               if (ret < 0)
+                       return ret;
+
+               ret = FIELD_GET(GENMASK(10, 0), ret);
+               break;
+       case PMBUS_VOUT_OV_FAULT_LIMIT:
+               ret = pmbus_read_word_data(client, page, phase, reg);
+               if (ret < 0)
+                       return ret;
+
+               if (FIELD_GET(GENMASK(12, 9), ret))
+                       ret = FIELD_GET(GENMASK(8, 0), ret) * MP2869_OVUV_LIMIT_SCALE +
+                               (FIELD_GET(GENMASK(12, 9), ret) + 1) * MP2869_OVUV_DELTA_SCALE;
+               else
+                       ret = FIELD_GET(GENMASK(8, 0), ret) * MP2869_OVUV_LIMIT_SCALE;
+               break;
+       case PMBUS_VOUT_UV_FAULT_LIMIT:
+               ret = pmbus_read_word_data(client, page, phase, reg);
+               if (ret < 0)
+                       return ret;
+
+               if (FIELD_GET(GENMASK(12, 9), ret))
+                       ret = FIELD_GET(GENMASK(8, 0), ret) * MP2869_OVUV_LIMIT_SCALE -
+                               (FIELD_GET(GENMASK(12, 9), ret) + 1) * MP2869_OVUV_DELTA_SCALE;
+               else
+                       ret = FIELD_GET(GENMASK(8, 0), ret) * MP2869_OVUV_LIMIT_SCALE;
+               break;
+       case PMBUS_OT_FAULT_LIMIT:
+       case PMBUS_OT_WARN_LIMIT:
+               /*
+                * The scale of MP2869 PMBUS_OT_FAULT_LIMIT and PMBUS_OT_WARN_LIMIT
+                * is 1°C/LSB and they have 40°C offset.
+                */
+               ret = pmbus_read_word_data(client, page, phase, reg);
+               if (ret < 0)
+                       return ret;
+
+               ret = (ret & GENMASK(7, 0)) - MP2869_TEMP_LIMIT_OFFSET;
+               break;
+       case PMBUS_VIN_OV_FAULT_LIMIT:
+               ret = pmbus_read_word_data(client, page, phase, reg);
+               if (ret < 0)
+                       return ret;
+
+               ret = (ret & GENMASK(7, 0)) * MP2869_VIN_OV_FAULT_GAIN;
+               break;
+       case PMBUS_VIN_UV_WARN_LIMIT:
+       case PMBUS_VIN_UV_FAULT_LIMIT:
+               ret = pmbus_read_word_data(client, page, phase, reg);
+               if (ret < 0)
+                       return ret;
+
+               ret = FIELD_GET(GENMASK(9, 0), ret);
+               break;
+       case PMBUS_IOUT_OC_FAULT_LIMIT:
+       case PMBUS_IOUT_OC_WARN_LIMIT:
+               ret = pmbus_read_word_data(client, page, phase, reg);
+               if (ret < 0)
+                       return ret;
+
+               ret = DIV_ROUND_CLOSEST((ret & GENMASK(7, 0)) * data->iout_scale[page] *
+                                               MP2869_IOUT_LIMIT_UINT, MP2869_READ_IOUT_DIV);
+               break;
+       case PMBUS_POUT_OP_WARN_LIMIT:
+               ret = pmbus_read_word_data(client, page, phase, reg);
+               if (ret < 0)
+                       return ret;
+
+               ret = (ret & GENMASK(7, 0)) * MP2869_POUT_OP_GAIN;
+               break;
+       default:
+               ret = -EINVAL;
+               break;
+       }
+
+       return ret;
+}
+
+static int mp2869_write_word_data(struct i2c_client *client, int page, int reg,
+                                 u16 word)
+{
+       const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
+       struct mp2869_data *data = to_mp2869_data(info);
+       int ret;
+
+       switch (reg) {
+       case PMBUS_VOUT_UV_FAULT_LIMIT:
+               /*
+                * The MP2869 PMBUS_VOUT_UV_FAULT_LIMIT[8:0] is the limit value,
+                * and bit9-bit15 should not be changed.
+                */
+               ret = pmbus_read_word_data(client, page, 0xff, reg);
+               if (ret < 0)
+                       return ret;
+
+               if (FIELD_GET(GENMASK(12, 9), ret))
+                       ret = pmbus_write_word_data(client, page, reg,
+                                                   (ret & ~GENMASK(8, 0)) |
+                               FIELD_PREP(GENMASK(8, 0),
+                                          DIV_ROUND_CLOSEST(word +
+                                               (FIELD_GET(GENMASK(12, 9),
+                                               ret) + 1) *
+                                       MP2869_OVUV_DELTA_SCALE,
+                                       MP2869_OVUV_LIMIT_SCALE)));
+               else
+                       ret = pmbus_write_word_data(client, page, reg,
+                                                   (ret & ~GENMASK(8, 0)) |
+                                       FIELD_PREP(GENMASK(8, 0),
+                                                  DIV_ROUND_CLOSEST(word,
+                                                                    MP2869_OVUV_LIMIT_SCALE)));
+               break;
+       case PMBUS_VOUT_OV_FAULT_LIMIT:
+               /*
+                * The MP2869 PMBUS_VOUT_OV_FAULT_LIMIT[8:0] is the limit value,
+                * and bit9-bit15 should not be changed.
+                */
+               ret = pmbus_read_word_data(client, page, 0xff, reg);
+               if (ret < 0)
+                       return ret;
+
+               if (FIELD_GET(GENMASK(12, 9), ret))
+                       ret = pmbus_write_word_data(client, page, reg,
+                                                   (ret & ~GENMASK(8, 0)) |
+                               FIELD_PREP(GENMASK(8, 0),
+                                          DIV_ROUND_CLOSEST(word -
+                                                       (FIELD_GET(GENMASK(12, 9),
+                                                       ret) + 1) *
+                                               MP2869_OVUV_DELTA_SCALE,
+                                               MP2869_OVUV_LIMIT_SCALE)));
+               else
+                       ret = pmbus_write_word_data(client, page, reg,
+                                                   (ret & ~GENMASK(8, 0)) |
+                               FIELD_PREP(GENMASK(8, 0),
+                                          DIV_ROUND_CLOSEST(word,
+                                                            MP2869_OVUV_LIMIT_SCALE)));
+               break;
+       case PMBUS_OT_FAULT_LIMIT:
+       case PMBUS_OT_WARN_LIMIT:
+               /*
+                * If the tsns digital fault is enabled, the PMBUS_OT_FAULT_LIMIT and
+                * PMBUS_OT_WARN_LIMIT can not be written.
+                */
+               if (data->mfr_thwn_flt_en)
+                       return -EINVAL;
+
+               /*
+                * The MP2869 scale of MP2869 PMBUS_OT_FAULT_LIMIT and PMBUS_OT_WARN_LIMIT
+                * have 40°C offset. The bit0-bit7 is the limit value, and bit8-bit15
+                * should not be changed.
+                */
+               ret = pmbus_read_word_data(client, page, 0xff, reg);
+               if (ret < 0)
+                       return ret;
+
+               ret = pmbus_write_word_data(client, page, reg,
+                                           (ret & ~GENMASK(7, 0)) |
+                                        FIELD_PREP(GENMASK(7, 0),
+                                                   word + MP2869_TEMP_LIMIT_OFFSET));
+               break;
+       case PMBUS_VIN_OV_FAULT_LIMIT:
+               /*
+                * The MP2869 PMBUS_VIN_OV_FAULT_LIMIT[7:0] is the limit value, and bit8-bit15
+                * should not be changed. The scale of PMBUS_VIN_OV_FAULT_LIMIT is 125mV/Lsb,
+                * but the vin scale is set to 31.25mV/Lsb(using r/m/b scale), so the word data
+                * should divide by MP2869_VIN_OV_FAULT_GAIN(4)
+                */
+               ret = pmbus_read_word_data(client, page, 0xff, reg);
+               if (ret < 0)
+                       return ret;
+
+               ret = pmbus_write_word_data(client, page, reg,
+                                           (ret & ~GENMASK(7, 0)) |
+                                       FIELD_PREP(GENMASK(7, 0),
+                                                  DIV_ROUND_CLOSEST(word,
+                                                                    MP2869_VIN_OV_FAULT_GAIN)));
+               break;
+       case PMBUS_VIN_UV_WARN_LIMIT:
+       case PMBUS_VIN_UV_FAULT_LIMIT:
+               /*
+                * The PMBUS_VIN_UV_LIMIT[9:0] is the limit value, and bit10-bit15 should
+                * not be changed. The scale of PMBUS_VIN_UV_LIMIT is 31.25mV/Lsb, and the
+                * vin scale is set to 31.25mV/Lsb(using r/m/b scale), so the word data can
+                * be written directly.
+                */
+               ret = pmbus_read_word_data(client, page, 0xff, reg);
+               if (ret < 0)
+                       return ret;
+
+               ret = pmbus_write_word_data(client, page, reg,
+                                           (ret & ~GENMASK(9, 0)) |
+                                               FIELD_PREP(GENMASK(9, 0),
+                                                          word));
+               break;
+       case PMBUS_IOUT_OC_FAULT_LIMIT:
+       case PMBUS_IOUT_OC_WARN_LIMIT:
+               ret = pmbus_write_word_data(client, page, reg,
+                                           DIV_ROUND_CLOSEST(word * MP2869_READ_IOUT_DIV,
+                                                             MP2869_IOUT_LIMIT_UINT *
+                                                                 data->iout_scale[page]));
+               break;
+       case PMBUS_POUT_OP_WARN_LIMIT:
+               /*
+                * The POUT_OP_WARN_LIMIT[11:0] is the limit value, and bit12-bit15 should
+                * not be changed. The scale of POUT_OP_WARN_LIMIT is 2W/Lsb.
+                */
+               ret = pmbus_read_word_data(client, page, 0xff, reg);
+               if (ret < 0)
+                       return ret;
+
+               ret = pmbus_write_word_data(client, page, reg,
+                                           (ret & ~GENMASK(11, 0)) |
+                                       FIELD_PREP(GENMASK(11, 0),
+                                                  DIV_ROUND_CLOSEST(word,
+                                                                    MP2869_POUT_OP_GAIN)));
+               break;
+       default:
+               ret = -EINVAL;
+               break;
+       }
+
+       return ret;
+}
+
+static int mp2869_identify(struct i2c_client *client, struct pmbus_driver_info *info)
+{
+       int ret;
+
+       /* Identify whether tsns digital fault is enable */
+       ret = mp2869_identify_thwn_flt(client, info, 1);
+       if (ret < 0)
+               return 0;
+
+       /* Identify vout scale for rail1. */
+       ret = mp2869_identify_vout_scale(client, info, 0);
+       if (ret < 0)
+               return ret;
+
+       /* Identify vout scale for rail2. */
+       ret = mp2869_identify_vout_scale(client, info, 1);
+       if (ret < 0)
+               return ret;
+
+       /* Identify iout scale for rail 1. */
+       ret = mp2869_identify_iout_scale(client, info, 0);
+       if (ret < 0)
+               return ret;
+
+       /* Identify iout scale for rail 2. */
+       return mp2869_identify_iout_scale(client, info, 1);
+}
+
+static const struct pmbus_driver_info mp2869_info = {
+       .pages = MP2869_PAGE_NUM,
+       .format[PSC_VOLTAGE_IN] = direct,
+       .format[PSC_CURRENT_IN] = linear,
+       .format[PSC_CURRENT_OUT] = direct,
+       .format[PSC_TEMPERATURE] = direct,
+       .format[PSC_POWER] = direct,
+       .format[PSC_VOLTAGE_OUT] = direct,
+
+       .m[PSC_VOLTAGE_IN] = 32,
+       .R[PSC_VOLTAGE_IN] = 0,
+       .b[PSC_VOLTAGE_IN] = 0,
+
+       .m[PSC_VOLTAGE_OUT] = 1,
+       .R[PSC_VOLTAGE_OUT] = 3,
+       .b[PSC_VOLTAGE_OUT] = 0,
+
+       .m[PSC_CURRENT_OUT] = 1,
+       .R[PSC_CURRENT_OUT] = 0,
+       .b[PSC_CURRENT_OUT] = 0,
+
+       .m[PSC_TEMPERATURE] = 1,
+       .R[PSC_TEMPERATURE] = 0,
+       .b[PSC_TEMPERATURE] = 0,
+
+       .m[PSC_POWER] = 1,
+       .R[PSC_POWER] = 0,
+       .b[PSC_POWER] = 0,
+
+       .func[0] = MP2869_RAIL1_FUNC,
+       .func[1] = MP2869_RAIL2_FUNC,
+       .read_word_data = mp2869_read_word_data,
+       .write_word_data = mp2869_write_word_data,
+       .read_byte_data = mp2869_read_byte_data,
+       .identify = mp2869_identify,
+};
+
+static int mp2869_probe(struct i2c_client *client)
+{
+       struct pmbus_driver_info *info;
+       struct mp2869_data *data;
+
+       data = devm_kzalloc(&client->dev, sizeof(struct mp2869_data),
+                           GFP_KERNEL);
+       if (!data)
+               return -ENOMEM;
+
+       memcpy(&data->info, &mp2869_info, sizeof(*info));
+       info = &data->info;
+
+       return pmbus_do_probe(client, info);
+}
+
+static const struct i2c_device_id mp2869_id[] = {
+       {"mp2869", 0},
+       {"mp29608", 1},
+       {"mp29612", 2},
+       {"mp29816", 3},
+       {}
+};
+MODULE_DEVICE_TABLE(i2c, mp2869_id);
+
+static const struct of_device_id __maybe_unused mp2869_of_match[] = {
+       {.compatible = "mps,mp2869", .data = (void *)0},
+       {.compatible = "mps,mp29608", .data = (void *)1},
+       {.compatible = "mps,mp29612", .data = (void *)2},
+       {.compatible = "mps,mp29816", .data = (void *)3},
+       {}
+};
+MODULE_DEVICE_TABLE(of, mp2869_of_match);
+
+static struct i2c_driver mp2869_driver = {
+       .driver = {
+               .name = "mp2869",
+               .of_match_table = mp2869_of_match,
+       },
+       .probe = mp2869_probe,
+       .id_table = mp2869_id,
+};
+
+module_i2c_driver(mp2869_driver);
+
+MODULE_AUTHOR("Wensheng Wang <wenswang@yeah.net>");
+MODULE_DESCRIPTION("PMBus driver for MPS MP2869");
+MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS("PMBUS");