Adding upstream version 6.8.9.upstream/6.8.9

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

7 files changed, 870 insertions, 11 deletions

diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig
index b4e93bd583..294808f524 100644
--- a/drivers/hwmon/pmbus/Kconfig
+++ b/drivers/hwmon/pmbus/Kconfig
@@ -227,6 +227,16 @@ config SENSORS_LTC3815
 	  This driver can also be built as a module. If so, the module will
 	  be called ltc3815.
 
+config SENSORS_LTC4286
+	bool "Analog Devices LTC4286"
+	help
+	  LTC4286 is an integrated solution for hot swap applications that
+	  allows a board to be safely inserted and removed from a live
+	  backplane.
+	  This chip could be used to monitor voltage, current, ...etc.
+	  If you say yes here you get hardware monitoring support for Analog
+	  Devices LTC4286.
+
 config SENSORS_MAX15301
 	tristate "Maxim MAX15301"
 	help
@@ -299,6 +309,15 @@ config SENSORS_MAX8688
 	  This driver can also be built as a module. If so, the module will
 	  be called max8688.
 
+config SENSORS_MP2856
+	tristate "MPS MP2856"
+	help
+	  If you say yes here you get hardware monitoring support for MPS
+	  MP2856 MP2857 Dual Loop Digital Multi-Phase Controller.
+
+	  This driver can also be built as a module. If so, the module will
+	  be called mp2856.
+
 config SENSORS_MP2888
 	tristate "MPS MP2888"
 	help
@@ -333,6 +352,15 @@ config SENSORS_MP5023
 	  This driver can also be built as a module. If so, the module will
 	  be called mp5023.
 
+config SENSORS_MP5990
+	tristate "MPS MP5990"
+	help
+	  If you say yes here you get hardware monitoring support for MPS
+	  MP5990.
+
+	  This driver can also be built as a module. If so, the module will
+	  be called mp5990.
+
 config SENSORS_MPQ7932_REGULATOR
 	bool "Regulator support for MPQ7932"
 	depends on SENSORS_MPQ7932 && REGULATOR
diff --git a/drivers/hwmon/pmbus/Makefile b/drivers/hwmon/pmbus/Makefile
index 84ee960a6c..cf8a767445 100644
--- a/drivers/hwmon/pmbus/Makefile
+++ b/drivers/hwmon/pmbus/Makefile
@@ -24,6 +24,7 @@ obj-$(CONFIG_SENSORS_LM25066)	+= lm25066.o
 obj-$(CONFIG_SENSORS_LT7182S)	+= lt7182s.o
 obj-$(CONFIG_SENSORS_LTC2978)	+= ltc2978.o
 obj-$(CONFIG_SENSORS_LTC3815)	+= ltc3815.o
+obj-$(CONFIG_SENSORS_LTC4286)	+= ltc4286.o
 obj-$(CONFIG_SENSORS_MAX15301)	+= max15301.o
 obj-$(CONFIG_SENSORS_MAX16064)	+= max16064.o
 obj-$(CONFIG_SENSORS_MAX16601)	+= max16601.o
@@ -32,9 +33,11 @@ obj-$(CONFIG_SENSORS_MAX20751)	+= max20751.o
 obj-$(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_MP2888)	+= mp2888.o
 obj-$(CONFIG_SENSORS_MP2975)	+= mp2975.o
 obj-$(CONFIG_SENSORS_MP5023)	+= mp5023.o
+obj-$(CONFIG_SENSORS_MP5990)	+= mp5990.o
 obj-$(CONFIG_SENSORS_MPQ7932)	+= mpq7932.o
 obj-$(CONFIG_SENSORS_PLI1209BC)	+= pli1209bc.o
 obj-$(CONFIG_SENSORS_PM6764TR)	+= pm6764tr.o
diff --git a/drivers/hwmon/pmbus/lm25066.c b/drivers/hwmon/pmbus/lm25066.c
index 929fa6d34e..3a20df5a43 100644
--- a/drivers/hwmon/pmbus/lm25066.c
+++ b/drivers/hwmon/pmbus/lm25066.c
@@ -14,10 +14,10 @@
 #include <linux/slab.h>
 #include <linux/i2c.h>
 #include <linux/log2.h>
-#include <linux/of_device.h>
+#include <linux/of.h>
 #include "pmbus.h"
 
-enum chips { lm25056, lm25066, lm5064, lm5066, lm5066i };
+enum chips { lm25056 = 1, lm25066, lm5064, lm5066, lm5066i };
 
 #define LM25066_READ_VAUX		0xd0
 #define LM25066_MFR_READ_IIN		0xd1
@@ -468,8 +468,6 @@ static int lm25066_probe(struct i2c_client *client)
 	struct lm25066_data *data;
 	struct pmbus_driver_info *info;
 	const struct __coeff *coeff;
-	const struct of_device_id *of_id;
-	const struct i2c_device_id *i2c_id;
 
 	if (!i2c_check_functionality(client->adapter,
 				     I2C_FUNC_SMBUS_READ_BYTE_DATA))
@@ -484,14 +482,8 @@ static int lm25066_probe(struct i2c_client *client)
 	if (config < 0)
 		return config;
 
-	i2c_id = i2c_match_id(lm25066_id, client);
+	data->id = (enum chips)(unsigned long)i2c_get_match_data(client);
 
-	of_id = of_match_device(lm25066_of_match, &client->dev);
-	if (of_id && (unsigned long)of_id->data != i2c_id->driver_data)
-		dev_notice(&client->dev, "Device mismatch: %s in device tree, %s detected\n",
-			   of_id->name, i2c_id->name);
-
-	data->id = i2c_id->driver_data;
 	info = &data->info;
 
 	info->pages = 1;
diff --git a/drivers/hwmon/pmbus/ltc4286.c b/drivers/hwmon/pmbus/ltc4286.c
new file mode 100644
index 0000000000..9e7ceeb7e7
--- /dev/null
+++ b/drivers/hwmon/pmbus/ltc4286.c
@@ -0,0 +1,175 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pmbus.h>
+#include "pmbus.h"
+
+/* LTC4286 register */
+#define LTC4286_MFR_CONFIG1	0xF2
+
+/* LTC4286 configuration */
+#define VRANGE_SELECT_BIT	BIT(1)
+
+#define LTC4286_MFR_ID_SIZE	3
+
+/*
+ * Initialize the MBR as default settings which is referred to LTC4286 datasheet
+ * (March 22, 2022 version) table 3 page 16
+ */
+static struct pmbus_driver_info ltc4286_info = {
+	.pages = 1,
+	.format[PSC_VOLTAGE_IN] = direct,
+	.format[PSC_VOLTAGE_OUT] = direct,
+	.format[PSC_CURRENT_OUT] = direct,
+	.format[PSC_POWER] = direct,
+	.format[PSC_TEMPERATURE] = direct,
+	.m[PSC_VOLTAGE_IN] = 32,
+	.b[PSC_VOLTAGE_IN] = 0,
+	.R[PSC_VOLTAGE_IN] = 1,
+	.m[PSC_VOLTAGE_OUT] = 32,
+	.b[PSC_VOLTAGE_OUT] = 0,
+	.R[PSC_VOLTAGE_OUT] = 1,
+	.m[PSC_CURRENT_OUT] = 1024,
+	.b[PSC_CURRENT_OUT] = 0,
+	/*
+	 * The rsense value used in MBR formula in LTC4286 datasheet should be ohm unit.
+	 * However, the rsense value that user input is micro ohm.
+	 * Thus, the MBR setting which involves rsense should be shifted by 6 digits.
+	 */
+	.R[PSC_CURRENT_OUT] = 3 - 6,
+	.m[PSC_POWER] = 1,
+	.b[PSC_POWER] = 0,
+	/*
+	 * The rsense value used in MBR formula in LTC4286 datasheet should be ohm unit.
+	 * However, the rsense value that user input is micro ohm.
+	 * Thus, the MBR setting which involves rsense should be shifted by 6 digits.
+	 */
+	.R[PSC_POWER] = 4 - 6,
+	.m[PSC_TEMPERATURE] = 1,
+	.b[PSC_TEMPERATURE] = 273,
+	.R[PSC_TEMPERATURE] = 0,
+	.func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT |
+		   PMBUS_HAVE_PIN | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_VOUT |
+		   PMBUS_HAVE_STATUS_IOUT | PMBUS_HAVE_STATUS_TEMP,
+};
+
+static const struct i2c_device_id ltc4286_id[] = {
+	{ "ltc4286", 0 },
+	{ "ltc4287", 1 },
+	{}
+};
+MODULE_DEVICE_TABLE(i2c, ltc4286_id);
+
+static int ltc4286_probe(struct i2c_client *client)
+{
+	int ret;
+	const struct i2c_device_id *mid;
+	u8 block_buffer[I2C_SMBUS_BLOCK_MAX + 1];
+	struct pmbus_driver_info *info;
+	u32 rsense;
+	int vrange_nval, vrange_oval;
+
+	ret = i2c_smbus_read_block_data(client, PMBUS_MFR_ID, block_buffer);
+	if (ret < 0) {
+		return dev_err_probe(&client->dev, ret,
+				     "Failed to read manufacturer id\n");
+	}
+
+	/*
+	 * Refer to ltc4286 datasheet page 20
+	 * the manufacturer id is LTC
+	 */
+	if (ret != LTC4286_MFR_ID_SIZE ||
+	    strncmp(block_buffer, "LTC", LTC4286_MFR_ID_SIZE)) {
+		return dev_err_probe(&client->dev, -ENODEV,
+				     "Manufacturer id mismatch\n");
+	}
+
+	ret = i2c_smbus_read_block_data(client, PMBUS_MFR_MODEL, block_buffer);
+	if (ret < 0) {
+		return dev_err_probe(&client->dev, ret,
+				     "Failed to read manufacturer model\n");
+	}
+
+	for (mid = ltc4286_id; mid->name[0]; mid++) {
+		if (!strncasecmp(mid->name, block_buffer, strlen(mid->name)))
+			break;
+	}
+	if (!mid->name[0])
+		return dev_err_probe(&client->dev, -ENODEV,
+				     "Unsupported device\n");
+
+	if (of_property_read_u32(client->dev.of_node,
+				 "shunt-resistor-micro-ohms", &rsense))
+		rsense = 300; /* 0.3 mOhm if not set via DT */
+
+	if (rsense == 0)
+		return -EINVAL;
+
+	/* Check for the latter MBR value won't overflow */
+	if (rsense > (INT_MAX / 1024))
+		return -EINVAL;
+
+	info = devm_kmemdup(&client->dev, &ltc4286_info, sizeof(*info),
+			    GFP_KERNEL);
+	if (!info)
+		return -ENOMEM;
+
+	/* Check MFR1 CONFIG register bit 1 VRANGE_SELECT before driver loading */
+	vrange_oval = i2c_smbus_read_word_data(client, LTC4286_MFR_CONFIG1);
+	if (vrange_oval < 0)
+		return dev_err_probe(&client->dev, vrange_oval,
+				     "Failed to read manufacturer configuration one\n");
+	vrange_nval = vrange_oval;
+
+	if (device_property_read_bool(&client->dev, "adi,vrange-low-enable")) {
+		vrange_nval &=
+			~VRANGE_SELECT_BIT; /* VRANGE_SELECT = 0, 25.6 volts */
+
+		info->m[PSC_VOLTAGE_IN] = 128;
+		info->m[PSC_VOLTAGE_OUT] = 128;
+		info->m[PSC_POWER] = 4 * rsense;
+	} else {
+		vrange_nval |=
+			VRANGE_SELECT_BIT; /* VRANGE_SELECT = 1, 102.4 volts */
+
+		info->m[PSC_POWER] = rsense;
+	}
+	if (vrange_nval != vrange_oval) {
+		/* Set MFR1 CONFIG register bit 1 VRANGE_SELECT */
+		ret = i2c_smbus_write_word_data(client, LTC4286_MFR_CONFIG1,
+						vrange_nval);
+		if (ret < 0)
+			return dev_err_probe(&client->dev, ret,
+					     "Failed to set vrange\n");
+	}
+
+	info->m[PSC_CURRENT_OUT] = 1024 * rsense;
+
+	return pmbus_do_probe(client, info);
+}
+
+static const struct of_device_id ltc4286_of_match[] = {
+	{ .compatible = "lltc,ltc4286" },
+	{ .compatible = "lltc,ltc4287" },
+	{}
+};
+
+static struct i2c_driver ltc4286_driver = {
+	.driver = {
+		.name = "ltc4286",
+		.of_match_table = ltc4286_of_match,
+	},
+	.probe = ltc4286_probe,
+	.id_table = ltc4286_id,
+};
+
+module_i2c_driver(ltc4286_driver);
+
+MODULE_AUTHOR("Delphine CC Chiu <Delphine_CC_Chiu@wiwynn.com>");
+MODULE_DESCRIPTION("PMBUS driver for LTC4286 and compatibles");
+MODULE_LICENSE("GPL");
diff --git a/drivers/hwmon/pmbus/mp2856.c b/drivers/hwmon/pmbus/mp2856.c
new file mode 100644
index 0000000000..6969350f5d
--- /dev/null
+++ b/drivers/hwmon/pmbus/mp2856.c
@@ -0,0 +1,466 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Hardware monitoring driver for MPS2856/2857
+ * Monolithic Power Systems VR Controllers
+ *
+ * Copyright (C) 2023 Quanta Computer lnc.
+ */
+
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pmbus.h>
+#include "pmbus.h"
+
+/* Vendor specific registers. */
+#define MP2856_MFR_VR_MULTI_CONFIG_R1	0x0d
+#define MP2856_MFR_VR_MULTI_CONFIG_R2	0x1d
+
+#define MP2856_MUL1_BOOT_SR_R2		0x10
+#define MP2856_VR_ACTIVE		BIT(15)
+
+#define MP2856_MFR_VR_CONFIG2		0x5e
+#define MP2856_VOUT_MODE		BIT(11)
+
+#define MP2856_MFR_VR_CONFIG1		0x68
+#define MP2856_DRMOS_KCS		GENMASK(13, 12)
+
+#define MP2856_MFR_READ_CS1_2_R1	0x82
+#define MP2856_MFR_READ_CS3_4_R1	0x83
+#define MP2856_MFR_READ_CS5_6_R1	0x84
+#define MP2856_MFR_READ_CS7_8_R1	0x85
+#define MP2856_MFR_READ_CS9_10_R1	0x86
+#define MP2856_MFR_READ_CS11_12_R1	0x87
+
+#define MP2856_MFR_READ_CS1_2_R2	0x85
+#define MP2856_MFR_READ_CS3_4_R2	0x86
+#define MP2856_MFR_READ_CS5_6_R2	0x87
+
+#define MP2856_MAX_PHASE_RAIL1		8
+#define MP2856_MAX_PHASE_RAIL2		4
+
+#define MP2857_MAX_PHASE_RAIL1		12
+#define MP2857_MAX_PHASE_RAIL2		4
+
+#define MP2856_PAGE_NUM			2
+
+enum chips { mp2856 = 1, mp2857 };
+
+static const int mp2856_max_phases[][MP2856_PAGE_NUM] = {
+	[mp2856] = { MP2856_MAX_PHASE_RAIL1, MP2856_MAX_PHASE_RAIL2 },
+	[mp2857] = { MP2857_MAX_PHASE_RAIL1, MP2857_MAX_PHASE_RAIL2 },
+};
+
+static const struct i2c_device_id mp2856_id[] = {
+	{"mp2856", mp2856},
+	{"mp2857", mp2857},
+	{}
+};
+
+MODULE_DEVICE_TABLE(i2c, mp2856_id);
+
+struct mp2856_data {
+	struct pmbus_driver_info info;
+	int vout_format[MP2856_PAGE_NUM];
+	int curr_sense_gain[MP2856_PAGE_NUM];
+	int max_phases[MP2856_PAGE_NUM];
+	enum chips chip_id;
+};
+
+#define to_mp2856_data(x)	container_of(x, struct mp2856_data, info)
+
+#define MAX_LIN_MANTISSA	(1023 * 1000)
+#define MIN_LIN_MANTISSA	(511 * 1000)
+
+static u16 val2linear11(s64 val)
+{
+	s16 exponent = 0, mantissa;
+	bool negative = false;
+
+	if (val == 0)
+		return 0;
+
+	if (val < 0) {
+		negative = true;
+		val = -val;
+	}
+
+	/* Reduce large mantissa until it fits into 10 bit */
+	while (val >= MAX_LIN_MANTISSA && exponent < 15) {
+		exponent++;
+		val >>= 1;
+	}
+	/* Increase small mantissa to improve precision */
+	while (val < MIN_LIN_MANTISSA && exponent > -15) {
+		exponent--;
+		val <<= 1;
+	}
+
+	/* Convert mantissa from milli-units to units */
+	mantissa = clamp_val(DIV_ROUND_CLOSEST_ULL(val, 1000), 0, 0x3ff);
+
+	/* restore sign */
+	if (negative)
+		mantissa = -mantissa;
+
+	/* Convert to 5 bit exponent, 11 bit mantissa */
+	return (mantissa & 0x7ff) | ((exponent << 11) & 0xf800);
+}
+
+static int
+mp2856_read_word_helper(struct i2c_client *client, int page, int phase, u8 reg,
+			u16 mask)
+{
+	int ret = pmbus_read_word_data(client, page, phase, reg);
+
+	return (ret > 0) ? ret & mask : ret;
+}
+
+static int
+mp2856_read_vout(struct i2c_client *client, struct mp2856_data *data, int page,
+		 int phase, u8 reg)
+{
+	int ret;
+
+	ret = mp2856_read_word_helper(client, page, phase, reg,
+				      GENMASK(9, 0));
+	if (ret < 0)
+		return ret;
+
+	/* convert vout result to direct format */
+	ret = (data->vout_format[page] == vid) ?
+		((ret + 49) * 5) : ((ret * 1000) >> 8);
+
+	return ret;
+}
+
+static int
+mp2856_read_phase(struct i2c_client *client, struct mp2856_data *data,
+		  int page, int phase, u8 reg)
+{
+	int ret;
+	int val;
+
+	ret = pmbus_read_word_data(client, page, phase, reg);
+	if (ret < 0)
+		return ret;
+
+	if (!((phase + 1) % MP2856_PAGE_NUM))
+		ret >>= 8;
+	ret &= 0xff;
+
+	/*
+	 * Output value is calculated as: (READ_CSx * 12.5mV - 1.23V) / (Kcs * Rcs)
+	 */
+	val = (ret * 125) - 12300;
+
+	return val2linear11(val);
+}
+
+static int
+mp2856_read_phases(struct i2c_client *client, struct mp2856_data *data,
+		   int page, int phase)
+{
+	int ret;
+
+	if (page == 0) {
+		switch (phase) {
+		case 0 ... 1:
+			ret = mp2856_read_phase(client, data, page, phase,
+						MP2856_MFR_READ_CS1_2_R1);
+			break;
+		case 2 ... 3:
+			ret = mp2856_read_phase(client, data, page, phase,
+						MP2856_MFR_READ_CS3_4_R1);
+			break;
+		case 4 ... 5:
+			ret = mp2856_read_phase(client, data, page, phase,
+						MP2856_MFR_READ_CS5_6_R1);
+			break;
+		case 6 ... 7:
+			ret = mp2856_read_phase(client, data, page, phase,
+						MP2856_MFR_READ_CS7_8_R1);
+			break;
+		default:
+			return -ENODATA;
+		}
+	} else {
+		switch (phase) {
+		case 0 ... 1:
+			ret = mp2856_read_phase(client, data, page, phase,
+						MP2856_MFR_READ_CS1_2_R2);
+			break;
+		case 2 ... 3:
+			ret = mp2856_read_phase(client, data, page, phase,
+						MP2856_MFR_READ_CS1_2_R2);
+			break;
+		default:
+			return -ENODATA;
+		}
+	}
+	return ret;
+}
+
+static int
+mp2856_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 mp2856_data *data = to_mp2856_data(info);
+	int ret;
+
+	switch (reg) {
+	case PMBUS_READ_VOUT:
+		ret = mp2856_read_vout(client, data, page, phase, reg);
+		break;
+	case PMBUS_READ_IOUT:
+		if (phase != 0xff)
+			ret = mp2856_read_phases(client, data, page, phase);
+		else
+			ret = pmbus_read_word_data(client, page, phase, reg);
+		break;
+	default:
+		return -ENODATA;
+	}
+
+	return ret;
+}
+
+static int
+mp2856_read_byte_data(struct i2c_client *client, int page, int reg)
+{
+	switch (reg) {
+	case PMBUS_VOUT_MODE:
+		/* Enforce VOUT direct format. */
+		return PB_VOUT_MODE_DIRECT;
+	default:
+		return -ENODATA;
+	}
+}
+
+static int
+mp2856_identify_multiphase(struct i2c_client *client, u8 reg, u8 max_phase,
+			   u16 mask)
+{
+	int ret;
+
+	ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, 2);
+	if (ret < 0)
+		return ret;
+
+	ret = i2c_smbus_read_word_data(client, reg);
+	if (ret < 0)
+		return ret;
+
+	ret &= mask;
+	return (ret >= max_phase) ? max_phase : ret;
+}
+
+static int
+mp2856_identify_multiphase_rail1(struct i2c_client *client,
+				 struct mp2856_data *data)
+{
+	int ret, i;
+
+	ret = mp2856_identify_multiphase(client, MP2856_MFR_VR_MULTI_CONFIG_R1,
+					 MP2856_MAX_PHASE_RAIL1, GENMASK(3, 0));
+	if (ret < 0)
+		return ret;
+
+	data->info.phases[0] = (ret > data->max_phases[0]) ?
+				data->max_phases[0] : ret;
+
+	for (i = 0 ; i < data->info.phases[0]; i++)
+		data->info.pfunc[i] |= PMBUS_HAVE_IOUT;
+
+	return 0;
+}
+
+static int
+mp2856_identify_multiphase_rail2(struct i2c_client *client,
+				 struct mp2856_data *data)
+{
+	int ret, i;
+
+	ret = mp2856_identify_multiphase(client, MP2856_MFR_VR_MULTI_CONFIG_R2,
+					 MP2856_MAX_PHASE_RAIL2, GENMASK(2, 0));
+	if (ret < 0)
+		return ret;
+
+	data->info.phases[1] = (ret > data->max_phases[1]) ?
+				data->max_phases[1] : ret;
+
+	for (i = 0 ; i < data->info.phases[0]; i++)
+		data->info.pfunc[i] |= PMBUS_HAVE_IOUT;
+
+	return 0;
+}
+
+static int
+mp2856_current_sense_gain_get(struct i2c_client *client,
+			      struct mp2856_data *data)
+{
+	int i, ret;
+
+	/*
+	 * Obtain DrMOS current sense gain of power stage from the register
+	 * MP2856_MFR_VR_CONFIG1, bits 13-12. The value is selected as below:
+	 * 00b - 5µA/A, 01b - 8.5µA/A, 10b - 9.7µA/A, 11b - 10µA/A. Other
+	 * values are invalid.
+	 */
+	for (i = 0 ; i < data->info.pages; i++) {
+		ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, i);
+		if (ret < 0)
+			return ret;
+		ret = i2c_smbus_read_word_data(client,
+					       MP2856_MFR_VR_CONFIG1);
+		if (ret < 0)
+			return ret;
+
+		switch ((ret & MP2856_DRMOS_KCS) >> 12) {
+		case 0:
+			data->curr_sense_gain[i] = 50;
+			break;
+		case 1:
+			data->curr_sense_gain[i] = 85;
+			break;
+		case 2:
+			data->curr_sense_gain[i] = 97;
+			break;
+		default:
+			data->curr_sense_gain[i] = 100;
+			break;
+		}
+	}
+	return 0;
+}
+
+static int
+mp2856_identify_vout_format(struct i2c_client *client,
+			    struct mp2856_data *data)
+{
+	int i, ret;
+
+	for (i = 0; i < data->info.pages; i++) {
+		ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, i);
+		if (ret < 0)
+			return ret;
+
+		ret = i2c_smbus_read_word_data(client, MP2856_MFR_VR_CONFIG2);
+		if (ret < 0)
+			return ret;
+
+		data->vout_format[i] = (ret & MP2856_VOUT_MODE) ? linear : vid;
+	}
+	return 0;
+}
+
+static bool
+mp2856_is_rail2_active(struct i2c_client *client)
+{
+	int ret;
+
+	ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, 2);
+	if (ret < 0)
+		return true;
+
+	ret = i2c_smbus_read_word_data(client, MP2856_MUL1_BOOT_SR_R2);
+	if (ret < 0)
+		return true;
+
+	return (ret & MP2856_VR_ACTIVE) ? true : false;
+}
+
+static struct pmbus_driver_info mp2856_info = {
+	.pages = MP2856_PAGE_NUM,
+	.format[PSC_VOLTAGE_IN] = linear,
+	.format[PSC_VOLTAGE_OUT] = direct,
+	.format[PSC_TEMPERATURE] = linear,
+	.format[PSC_CURRENT_IN] = linear,
+	.format[PSC_CURRENT_OUT] = linear,
+	.format[PSC_POWER] = linear,
+	.m[PSC_VOLTAGE_OUT] = 1,
+	.R[PSC_VOLTAGE_OUT] = 3,
+	.func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT |
+		PMBUS_HAVE_IIN | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT |
+		PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP | PMBUS_HAVE_POUT |
+		PMBUS_HAVE_PIN | PMBUS_HAVE_STATUS_INPUT,
+	.func[1] = PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_IOUT |
+		PMBUS_HAVE_STATUS_IOUT | PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP,
+	.read_byte_data = mp2856_read_byte_data,
+	.read_word_data = mp2856_read_word_data,
+};
+
+static int mp2856_probe(struct i2c_client *client)
+{
+	struct pmbus_driver_info *info;
+	struct mp2856_data *data;
+	int ret;
+
+	data = devm_kzalloc(&client->dev, sizeof(struct mp2856_data),
+			    GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->chip_id = (enum chips)(uintptr_t)i2c_get_match_data(client);
+
+	memcpy(data->max_phases, mp2856_max_phases[data->chip_id],
+	       sizeof(data->max_phases));
+
+	memcpy(&data->info, &mp2856_info, sizeof(*info));
+	info = &data->info;
+
+	/* Identify multiphase configuration. */
+	ret = mp2856_identify_multiphase_rail1(client, data);
+	if (ret < 0)
+		return ret;
+
+	if (mp2856_is_rail2_active(client)) {
+		ret = mp2856_identify_multiphase_rail2(client, data);
+		if (ret < 0)
+			return ret;
+	} else {
+		/* rail2 is not active */
+		info->pages = 1;
+	}
+
+	/* Obtain current sense gain of power stage. */
+	ret = mp2856_current_sense_gain_get(client, data);
+	if (ret)
+		return ret;
+
+	/* Identify vout format. */
+	ret = mp2856_identify_vout_format(client, data);
+	if (ret)
+		return ret;
+
+	/* set the device to page 0 */
+	i2c_smbus_write_byte_data(client, PMBUS_PAGE, 0);
+
+	return pmbus_do_probe(client, info);
+}
+
+static const struct of_device_id __maybe_unused mp2856_of_match[] = {
+	{.compatible = "mps,mp2856", .data = (void *)mp2856},
+	{.compatible = "mps,mp2857", .data = (void *)mp2857},
+	{}
+};
+MODULE_DEVICE_TABLE(of, mp2856_of_match);
+
+static struct i2c_driver mp2856_driver = {
+	.driver = {
+		.name = "mp2856",
+		.of_match_table = mp2856_of_match,
+	},
+	.probe = mp2856_probe,
+	.id_table = mp2856_id,
+};
+
+module_i2c_driver(mp2856_driver);
+
+MODULE_AUTHOR("Peter Yin <peter.yin@quantatw.com>");
+MODULE_DESCRIPTION("PMBus driver for MPS MP2856/MP2857 device");
+MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(PMBUS);
diff --git a/drivers/hwmon/pmbus/mp2975.c b/drivers/hwmon/pmbus/mp2975.c
index b9bb469e2d..e5fa10b3b8 100644
--- a/drivers/hwmon/pmbus/mp2975.c
+++ b/drivers/hwmon/pmbus/mp2975.c
@@ -126,6 +126,21 @@ static const struct regulator_desc __maybe_unused mp2975_reg_desc[] = {
 
 #define to_mp2975_data(x)  container_of(x, struct mp2975_data, info)
 
+static int mp2975_read_byte_data(struct i2c_client *client, int page, int reg)
+{
+	switch (reg) {
+	case PMBUS_VOUT_MODE:
+		/*
+		 * Report direct format as configured by MFR_DC_LOOP_CTRL.
+		 * Unlike on MP2971/MP2973 the reported VOUT_MODE isn't automatically
+		 * internally updated, but always reads as PB_VOUT_MODE_VID.
+		 */
+		return PB_VOUT_MODE_DIRECT;
+	default:
+		return -ENODATA;
+	}
+}
+
 static int
 mp2975_read_word_helper(struct i2c_client *client, int page, int phase, u8 reg,
 			u16 mask)
@@ -869,6 +884,7 @@ static struct pmbus_driver_info mp2975_info = {
 		PMBUS_HAVE_IIN | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT |
 		PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP | PMBUS_HAVE_POUT |
 		PMBUS_HAVE_PIN | PMBUS_HAVE_STATUS_INPUT | PMBUS_PHASE_VIRTUAL,
+	.read_byte_data = mp2975_read_byte_data,
 	.read_word_data = mp2975_read_word_data,
 #if IS_ENABLED(CONFIG_SENSORS_MP2975_REGULATOR)
 	.num_regulators = 1,
diff --git a/drivers/hwmon/pmbus/mp5990.c b/drivers/hwmon/pmbus/mp5990.c
new file mode 100644
index 0000000000..1dfbab25a0
--- /dev/null
+++ b/drivers/hwmon/pmbus/mp5990.c
@@ -0,0 +1,179 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Driver for MPS MP5990 Hot-Swap Controller
+ */
+
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include "pmbus.h"
+
+#define MP5990_EFUSE_CFG	(0xC4)
+#define MP5990_VOUT_FORMAT	BIT(9)
+
+struct mp5990_data {
+	struct pmbus_driver_info info;
+	u8 vout_mode;
+	u8 vout_linear_exponent;
+};
+
+#define to_mp5990_data(x)  container_of(x, struct mp5990_data, info)
+
+static int mp5990_read_byte_data(struct i2c_client *client, int page, int reg)
+{
+	const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
+	struct mp5990_data *data = to_mp5990_data(info);
+
+	switch (reg) {
+	case PMBUS_VOUT_MODE:
+		if (data->vout_mode == linear) {
+			/*
+			 * The VOUT format used by the chip is linear11,
+			 * not linear16. Report that VOUT is in linear mode
+			 * and return exponent value extracted while probing
+			 * the chip.
+			 */
+			return data->vout_linear_exponent;
+		}
+
+		/*
+		 * The datasheet does not support the VOUT command,
+		 * but the device responds with a default value of 0x17.
+		 * In the standard, 0x17 represents linear mode.
+		 * Therefore, we should report that VOUT is in direct
+		 * format when the chip is configured for it.
+		 */
+		return PB_VOUT_MODE_DIRECT;
+
+	default:
+		return -ENODATA;
+	}
+}
+
+static int mp5990_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 mp5990_data *data = to_mp5990_data(info);
+	int ret;
+	s32 mantissa;
+
+	switch (reg) {
+	case PMBUS_READ_VOUT:
+		ret = pmbus_read_word_data(client, page, phase, reg);
+		if (ret < 0)
+			return ret;
+		/*
+		 * Because the VOUT format used by the chip is linear11 and not
+		 * linear16, we disregard bits[15:11]. The exponent is reported
+		 * as part of the VOUT_MODE command.
+		 */
+		if (data->vout_mode == linear) {
+			mantissa = ((s16)((ret & 0x7ff) << 5)) >> 5;
+			ret = mantissa;
+		}
+		break;
+	default:
+		return -ENODATA;
+	}
+
+	return ret;
+}
+
+static struct pmbus_driver_info mp5990_info = {
+	.pages = 1,
+	.format[PSC_VOLTAGE_IN] = direct,
+	.format[PSC_VOLTAGE_OUT] = direct,
+	.format[PSC_CURRENT_OUT] = direct,
+	.format[PSC_POWER] = direct,
+	.format[PSC_TEMPERATURE] = direct,
+	.m[PSC_VOLTAGE_IN] = 32,
+	.b[PSC_VOLTAGE_IN] = 0,
+	.R[PSC_VOLTAGE_IN] = 0,
+	.m[PSC_VOLTAGE_OUT] = 32,
+	.b[PSC_VOLTAGE_OUT] = 0,
+	.R[PSC_VOLTAGE_OUT] = 0,
+	.m[PSC_CURRENT_OUT] = 16,
+	.b[PSC_CURRENT_OUT] = 0,
+	.R[PSC_CURRENT_OUT] = 0,
+	.m[PSC_POWER] = 1,
+	.b[PSC_POWER] = 0,
+	.R[PSC_POWER] = 0,
+	.m[PSC_TEMPERATURE] = 1,
+	.b[PSC_TEMPERATURE] = 0,
+	.R[PSC_TEMPERATURE] = 0,
+	.func[0] =
+		PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_PIN |
+		PMBUS_HAVE_TEMP | PMBUS_HAVE_IOUT |
+		PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP,
+	.read_byte_data = mp5990_read_byte_data,
+	.read_word_data = mp5990_read_word_data,
+};
+
+static int mp5990_probe(struct i2c_client *client)
+{
+	struct pmbus_driver_info *info;
+	struct mp5990_data *data;
+	int ret;
+
+	data = devm_kzalloc(&client->dev, sizeof(struct mp5990_data),
+			    GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	memcpy(&data->info, &mp5990_info, sizeof(*info));
+	info = &data->info;
+
+	/* Read Vout Config */
+	ret = i2c_smbus_read_word_data(client, MP5990_EFUSE_CFG);
+	if (ret < 0) {
+		dev_err(&client->dev, "Can't get vout mode.");
+		return ret;
+	}
+
+	/*
+	 * EFUSE_CFG (0xC4) bit9=1 is linear mode, bit=0 is direct mode.
+	 */
+	if (ret & MP5990_VOUT_FORMAT) {
+		data->vout_mode = linear;
+		data->info.format[PSC_VOLTAGE_IN] = linear;
+		data->info.format[PSC_VOLTAGE_OUT] = linear;
+		data->info.format[PSC_CURRENT_OUT] = linear;
+		data->info.format[PSC_POWER] = linear;
+		ret = i2c_smbus_read_word_data(client, PMBUS_READ_VOUT);
+		if (ret < 0) {
+			dev_err(&client->dev, "Can't get vout exponent.");
+			return ret;
+		}
+		data->vout_linear_exponent = (u8)((ret >> 11) & 0x1f);
+	} else {
+		data->vout_mode = direct;
+	}
+	return pmbus_do_probe(client, info);
+}
+
+static const struct of_device_id mp5990_of_match[] = {
+	{ .compatible = "mps,mp5990" },
+	{}
+};
+
+static const struct i2c_device_id mp5990_id[] = {
+	{"mp5990", 0},
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, mp5990_id);
+
+static struct i2c_driver mp5990_driver = {
+	.driver = {
+		   .name = "mp5990",
+		   .of_match_table = mp5990_of_match,
+	},
+	.probe = mp5990_probe,
+	.id_table = mp5990_id,
+};
+module_i2c_driver(mp5990_driver);
+
+MODULE_AUTHOR("Peter Yin <peter.yin@quantatw.com>");
+MODULE_DESCRIPTION("PMBus driver for MP5990 HSC");
+MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(PMBUS);