perf/x86/intel: Rename DMR offcore_rsp attribute to offmodule_rspgrafted

DMR introduces Offmodule Response events in place of the legacy
Offcore Response events, but it still exposes the inherited
offcore_rsp PMU attribute for programming the corresponding MSR data.

Rename the DMR PMU attribute to offmodule_rsp so the sysfs interface
matches the underlying event name and avoids user & tooling confusion.

Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://patch.msgid.link/20260917015234.981153-12-dapeng1.mi@linux.intel.com

1 files changed, 1795 insertions, 0 deletions

diff --git a/drivers/hwmon/ltc4283.c b/drivers/hwmon/ltc4283.c
new file mode 100644
index 000000000..9ec409bc2
--- /dev/null
+++ b/drivers/hwmon/ltc4283.c
@@ -0,0 +1,1795 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Analog Devices LTC4283 I2C Negative Voltage Hot Swap Controller (HWMON)
+ *
+ * Copyright 2025 Analog Devices Inc.
+ */
+#include <linux/auxiliary_bus.h>
+#include <linux/bitfield.h>
+#include <linux/bitmap.h>
+#include <linux/bitops.h>
+#include <linux/bits.h>
+
+#include <linux/debugfs.h>
+#include <linux/device.h>
+#include <linux/device/devres.h>
+#include <linux/hwmon.h>
+#include <linux/i2c.h>
+#include <linux/math.h>
+#include <linux/math64.h>
+#include <linux/minmax.h>
+#include <linux/module.h>
+
+#include <linux/property.h>
+#include <linux/regmap.h>
+#include <linux/unaligned.h>
+#include <linux/units.h>
+
+#define LTC4283_SYSTEM_STATUS		0x00
+#define LTC4283_FAULT_STATUS		0x03
+#define   LTC4283_OV_MASK		BIT(0)
+#define   LTC4283_UV_MASK		BIT(1)
+#define   LTC4283_OC_MASK		BIT(2)
+#define   LTC4283_FET_BAD_MASK		BIT(3)
+#define   LTC4283_FET_SHORT_MASK	BIT(6)
+#define LTC4283_FAULT_LOG		0x04
+#define   LTC4283_OV_FAULT_MASK		BIT(0)
+#define   LTC4283_UV_FAULT_MASK		BIT(1)
+#define   LTC4283_OC_FAULT_MASK		BIT(2)
+#define   LTC4283_FET_BAD_FAULT_MASK	BIT(3)
+#define   LTC4283_PGI_FAULT_MASK	BIT(4)
+#define   LTC4283_PWR_FAIL_FAULT_MASK	BIT(5)
+#define   LTC4283_FET_SHORT_FAULT_MASK	BIT(6)
+#define LTC4283_ADC_ALM_LOG_1		0x05
+#define   LTC4283_POWER_LOW_ALM		BIT(0)
+#define   LTC4283_POWER_HIGH_ALM	BIT(1)
+#define   LTC4283_SENSE_LOW_ALM		BIT(4)
+#define   LTC4283_SENSE_HIGH_ALM	BIT(5)
+#define LTC4283_ADC_ALM_LOG_2		0x06
+#define LTC4283_ADC_ALM_LOG_3		0x07
+#define LTC4283_ADC_ALM_LOG_4		0x08
+#define LTC4283_ADC_ALM_LOG_5		0x09
+#define LTC4283_CONTROL_1		0x0a
+#define   LTC4283_RW_PAGE_MASK		BIT(0)
+#define   LTC4283_PIGIO2_ACLB_MASK	BIT(2)
+#define   LTC4283_PWRGD_RST_CTRL_MASK	BIT(3)
+#define   LTC4283_FET_BAD_OFF_MASK	BIT(4)
+#define   LTC4283_THERM_TMR_MASK	BIT(5)
+#define   LTC4283_DVDT_MASK		BIT(6)
+#define LTC4283_CONTROL_2		0x0b
+#define   LTC4283_OV_RETRY_MASK		BIT(0)
+#define   LTC4283_UV_RETRY_MASK		BIT(1)
+#define   LTC4283_OC_RETRY_MASK		GENMASK(3, 2)
+#define   LTC4283_FET_BAD_RETRY_MASK	GENMASK(5, 4)
+#define   LTC4283_EXT_FAULT_RETRY_MASK	BIT(7)
+#define LTC4283_RESERVED_OC		0x0c
+#define LTC4283_CONFIG_1		0x0d
+#define   LTC4283_FB_MASK		GENMASK(3, 2)
+#define   LTC4283_ILIM_MASK		GENMASK(7, 4)
+#define LTC4283_CONFIG_2		0x0e
+#define   LTC4283_COOLING_DL_MASK	GENMASK(3, 1)
+#define   LTC4283_FTBD_DL_MASK		GENMASK(5, 4)
+#define LTC4283_CONFIG_3		0x0f
+#define   LTC4283_VPWR_DRNS_MASK	BIT(6)
+#define   LTC4283_EXTFLT_TURN_OFF_MASK	BIT(7)
+#define LTC4283_PGIO_CONFIG		0x10
+#define   LTC4283_PGIO1_CFG_MASK	GENMASK(1, 0)
+#define   LTC4283_PGIO2_CFG_MASK	GENMASK(3, 2)
+#define   LTC4283_PGIO3_CFG_MASK	GENMASK(5, 4)
+#define   LTC4283_PGIO4_CFG_MASK	GENMASK(7, 6)
+#define LTC4283_PGIO_CONFIG_2		0x11
+#define   LTC4283_ADC_MASK		GENMASK(2, 0)
+#define LTC4283_ADC_SELECT(c)		(0x13 + (c) / 8)
+#define   LTC4283_ADC_SELECT_MASK(c)	BIT((c) % 8)
+#define LTC4283_SENSE_MIN_TH		0x1b
+#define LTC4283_SENSE_MAX_TH		0x1c
+#define LTC4283_VPWR_MIN_TH		0x1d
+#define LTC4283_VPWR_MAX_TH		0x1e
+#define LTC4283_POWER_MIN_TH		0x1f
+#define LTC4283_POWER_MAX_TH		0x20
+#define LTC4283_ADC_2_MIN_TH(c)		(0x21 + (c) * 2)
+#define LTC4283_ADC_2_MAX_TH(c)		(0x22 + (c) * 2)
+#define LTC4283_ADC_2_MIN_TH_DIFF(c)	(0x39 + (c) * 2)
+#define LTC4283_ADC_2_MAX_TH_DIFF(c)	(0x3a + (c) * 2)
+#define LTC4283_SENSE			0x41
+#define LTC4283_SENSE_MIN		0x42
+#define LTC4283_SENSE_MAX		0x43
+#define LTC4283_VPWR			0x44
+#define LTC4283_VPWR_MIN		0x45
+#define LTC4283_VPWR_MAX		0x46
+#define LTC4283_POWER			0x47
+#define LTC4283_POWER_MIN		0x48
+#define LTC4283_POWER_MAX		0x49
+#define LTC4283_RESERVED_68		0x68
+#define LTC4283_RESERVED_6D		0x6D
+/* get channels from ADC 2 */
+#define LTC4283_ADC_2(c)		(0x4a + (c) * 3)
+#define LTC4283_ADC_2_MIN(c)		(0x4b + (c) * 3)
+#define LTC4283_ADC_2_MAX(c)		(0x4c + (c) * 3)
+#define LTC4283_ADC_2_DIFF(c)		(0x6e + (c) * 3)
+#define LTC4283_ADC_2_MIN_DIFF(c)	(0x6f + (c) * 3)
+#define LTC4283_ADC_2_MAX_DIFF(c)	(0x70 + (c) * 3)
+#define LTC4283_ENERGY			0x7a
+#define LTC4283_METER_CONTROL		0x84
+#define   LTC4283_INTEGRATE_I_MASK	BIT(0)
+#define   LTC4283_METER_HALT_MASK	BIT(6)
+#define LTC4283_RESERVED_86		0x86
+#define LTC4283_RESERVED_8F		0x8F
+#define LTC4283_FAULT_LOG_CTRL		0x90
+#define   LTC4283_FAULT_LOG_EN_MASK	BIT(7)
+#define LTC4283_RESERVED_91		0x91
+#define LTC4283_RESERVED_A1		0xA1
+#define LTC4283_RESERVED_A3		0xA3
+#define LTC4283_RESERVED_AC		0xAC
+#define LTC4283_POWER_PLAY_MSB		0xE7
+#define LTC4283_POWER_PLAY_LSB		0xE8
+#define LTC4283_RESERVED_F1		0xF1
+#define LTC4283_RESERVED_FF		0xFF
+
+/* also applies for differential channels */
+#define LTC4283_ADC1_FS_uV		32768
+#define LTC4283_ADC2_FS_mV		2048
+#define LTC4283_TCONV_uS		64103
+#define LTC4283_VILIM_MIN_uV		15000
+#define LTC4283_VILIM_MAX_uV		30000
+#define LTC4283_VILIM_RANGE	\
+	(LTC4283_VILIM_MAX_uV - LTC4283_VILIM_MIN_uV + 1)
+
+#define LTC4283_PGIO_FUNC_GPIO		2
+#define LTC4283_PGIO2_FUNC_ACLB		3
+
+/*
+ * Maximum value for rsense in nano ohms. The reasoning for this value is that
+ * it's the max value for which multiplying by 256 does not overflow long on
+ * 32bits. For the minimum value, is a sane minimum rsense for which power_max
+ * does not overflow 32bits.
+ */
+#define LTC4283_MAX_RSENSE	1677721599
+#define LTC4283_MIN_RSENSE	50000
+
+/* voltage channels */
+enum {
+	LTC4283_CHAN_VIN,
+	LTC4283_CHAN_VPWR,
+	LTC4283_CHAN_ADI_1,
+	LTC4283_CHAN_ADI_2,
+	LTC4283_CHAN_ADI_3,
+	LTC4283_CHAN_ADI_4,
+	LTC4283_CHAN_ADIO_1,
+	LTC4283_CHAN_ADIO_2,
+	LTC4283_CHAN_ADIO_3,
+	LTC4283_CHAN_ADIO_4,
+	LTC4283_CHAN_DRNS,
+	LTC4283_CHAN_DRAIN,
+	/* differential channels */
+	LTC4283_CHAN_ADIN12,
+	LTC4283_CHAN_ADIN34,
+	LTC4283_CHAN_ADIO12,
+	LTC4283_CHAN_ADIO34,
+	LTC4283_CHAN_MAX
+};
+
+/* Just for ease of use on the regmap  */
+#define LTC4283_ADIO34_MAX \
+	LTC4283_ADC_2_MAX_DIFF(LTC4283_CHAN_ADIO34 - LTC4283_CHAN_ADIN12)
+
+struct ltc4283_hwmon {
+	struct regmap *map;
+	struct i2c_client *client;
+	unsigned long gpio_mask;
+	unsigned long ch_enable_mask;
+	/* in microwatt */
+	unsigned long power_max;
+	/* in millivolt */
+	u32 vsense_max;
+	/* in tenths of microohm*/
+	u32 rsense;
+	bool energy_en;
+	bool ext_fault;
+};
+
+static int ltc4283_read_voltage_word(const struct ltc4283_hwmon *st,
+				     u32 reg, u32 fs, long *val)
+{
+	unsigned int __raw;
+	int ret;
+
+	ret = regmap_read(st->map, reg, &__raw);
+	if (ret)
+		return ret;
+
+	*val = DIV_ROUND_CLOSEST(__raw * fs, BIT(16));
+	return 0;
+}
+
+static int ltc4283_read_voltage_byte(const struct ltc4283_hwmon *st,
+				     u32 reg, u32 fs, long *val)
+{
+	int ret;
+	u32 in;
+
+	ret = regmap_read(st->map, reg, &in);
+	if (ret)
+		return ret;
+
+	*val = DIV_ROUND_CLOSEST(in * fs, BIT(8));
+	return 0;
+}
+
+static u32 ltc4283_in_reg(u32 attr, u32 channel)
+{
+	switch (attr) {
+	case hwmon_in_input:
+		if (channel == LTC4283_CHAN_VPWR)
+			return LTC4283_VPWR;
+		if (channel >= LTC4283_CHAN_ADI_1 && channel <= LTC4283_CHAN_DRAIN)
+			return LTC4283_ADC_2(channel - LTC4283_CHAN_ADI_1);
+		return LTC4283_ADC_2_DIFF(channel - LTC4283_CHAN_ADIN12);
+	case hwmon_in_highest:
+		if (channel == LTC4283_CHAN_VPWR)
+			return LTC4283_VPWR_MAX;
+		if (channel >= LTC4283_CHAN_ADI_1 && channel <= LTC4283_CHAN_DRAIN)
+			return LTC4283_ADC_2_MAX(channel - LTC4283_CHAN_ADI_1);
+		return LTC4283_ADC_2_MAX_DIFF(channel - LTC4283_CHAN_ADIN12);
+	case hwmon_in_lowest:
+		if (channel == LTC4283_CHAN_VPWR)
+			return LTC4283_VPWR_MIN;
+		if (channel >= LTC4283_CHAN_ADI_1 && channel <= LTC4283_CHAN_DRAIN)
+			return LTC4283_ADC_2_MIN(channel - LTC4283_CHAN_ADI_1);
+		return LTC4283_ADC_2_MIN_DIFF(channel - LTC4283_CHAN_ADIN12);
+	case hwmon_in_max:
+		if (channel == LTC4283_CHAN_VPWR)
+			return LTC4283_VPWR_MAX_TH;
+		if (channel >= LTC4283_CHAN_ADI_1 && channel <= LTC4283_CHAN_DRAIN)
+			return LTC4283_ADC_2_MAX_TH(channel - LTC4283_CHAN_ADI_1);
+		return LTC4283_ADC_2_MAX_TH_DIFF(channel - LTC4283_CHAN_ADIN12);
+	default:
+		if (channel == LTC4283_CHAN_VPWR)
+			return LTC4283_VPWR_MIN_TH;
+		if (channel >= LTC4283_CHAN_ADI_1 && channel <= LTC4283_CHAN_DRAIN)
+			return LTC4283_ADC_2_MIN_TH(channel - LTC4283_CHAN_ADI_1);
+		return LTC4283_ADC_2_MIN_TH_DIFF(channel - LTC4283_CHAN_ADIN12);
+	}
+}
+
+static int ltc4283_read_in_vals(const struct ltc4283_hwmon *st,
+				u32 attr, u32 channel, long *val)
+{
+	u32 reg = ltc4283_in_reg(attr, channel);
+	int ret;
+
+	if (channel < LTC4283_CHAN_ADIN12) {
+		if (attr != hwmon_in_max && attr != hwmon_in_min)
+			return ltc4283_read_voltage_word(st, reg,
+							 LTC4283_ADC2_FS_mV,
+							 val);
+
+		return ltc4283_read_voltage_byte(st, reg,
+						 LTC4283_ADC2_FS_mV, val);
+	}
+
+	if (attr != hwmon_in_max && attr != hwmon_in_min)
+		ret = ltc4283_read_voltage_word(st, reg,
+						LTC4283_ADC1_FS_uV, val);
+	else
+		ret = ltc4283_read_voltage_byte(st, reg,
+						LTC4283_ADC1_FS_uV, val);
+	if (ret)
+		return ret;
+
+	*val = DIV_ROUND_CLOSEST(*val, MILLI);
+	return 0;
+}
+
+static int ltc4283_read_alarm(struct ltc4283_hwmon *st, u32 reg,
+			      u32 mask, long *val)
+{
+	u32 alarm;
+	int ret;
+
+	ret = regmap_read(st->map, reg, &alarm);
+	if (ret)
+		return ret;
+
+	*val = !!(alarm & mask);
+
+	/* If not status/fault logs, clear the alarm after reading it. */
+	if (reg != LTC4283_FAULT_STATUS && reg != LTC4283_FAULT_LOG)
+		return regmap_write(st->map, reg, alarm & ~mask);
+
+	return 0;
+}
+
+static int ltc4283_read_in_alarm(struct ltc4283_hwmon *st, u32 channel,
+				 bool max_alm, long *val)
+{
+	if (channel == LTC4283_CHAN_VPWR)
+		return ltc4283_read_alarm(st, LTC4283_ADC_ALM_LOG_1,
+					  BIT(2 + max_alm), val);
+
+	if (channel >= LTC4283_CHAN_ADI_1 && channel <= LTC4283_CHAN_ADI_4) {
+		u32 bit = (channel - LTC4283_CHAN_ADI_1) * 2;
+		/*
+		 * Lower channels go to higher bits. We also want to go +1 down
+		 * in the min_alarm case.
+		 */
+		return ltc4283_read_alarm(st, LTC4283_ADC_ALM_LOG_2,
+					  BIT(7 - bit - !max_alm), val);
+	}
+
+	if (channel >= LTC4283_CHAN_ADIO_1 && channel <= LTC4283_CHAN_ADIO_4) {
+		u32 bit = (channel - LTC4283_CHAN_ADIO_1) * 2;
+
+		return ltc4283_read_alarm(st, LTC4283_ADC_ALM_LOG_3,
+					  BIT(7 - bit - !max_alm), val);
+	}
+
+	if (channel >= LTC4283_CHAN_ADIN12 && channel <= LTC4283_CHAN_ADIO34) {
+		u32 bit = (channel - LTC4283_CHAN_ADIN12) * 2;
+
+		return ltc4283_read_alarm(st, LTC4283_ADC_ALM_LOG_5,
+					  BIT(7 - bit - !max_alm), val);
+	}
+
+	if (channel == LTC4283_CHAN_DRNS)
+		return ltc4283_read_alarm(st, LTC4283_ADC_ALM_LOG_4,
+					  BIT(6 + max_alm), val);
+
+	return ltc4283_read_alarm(st, LTC4283_ADC_ALM_LOG_4, BIT(4 + max_alm),
+				  val);
+}
+
+static int ltc4283_read_in(struct ltc4283_hwmon *st, u32 attr, u32 channel,
+			   long *val)
+{
+	switch (attr) {
+	case hwmon_in_input:
+		if (!test_bit(channel, &st->ch_enable_mask))
+			return -ENODATA;
+
+		return ltc4283_read_in_vals(st, attr, channel, val);
+	case hwmon_in_highest:
+	case hwmon_in_lowest:
+	case hwmon_in_max:
+	case hwmon_in_min:
+		return ltc4283_read_in_vals(st, attr, channel, val);
+	case hwmon_in_max_alarm:
+		return ltc4283_read_in_alarm(st, channel, true, val);
+	case hwmon_in_min_alarm:
+		return ltc4283_read_in_alarm(st, channel, false, val);
+	case hwmon_in_crit_alarm:
+		return ltc4283_read_alarm(st, LTC4283_FAULT_STATUS,
+					  LTC4283_OV_MASK, val);
+	case hwmon_in_lcrit_alarm:
+		return ltc4283_read_alarm(st, LTC4283_FAULT_STATUS,
+					  LTC4283_UV_MASK, val);
+	case hwmon_in_fault:
+		/*
+		 * We report failure if we detect either a fer_bad or a
+		 * fet_short in the status register.
+		 */
+		return ltc4283_read_alarm(st, LTC4283_FAULT_STATUS,
+					  LTC4283_FET_BAD_MASK | LTC4283_FET_SHORT_MASK, val);
+	case hwmon_in_enable:
+		*val = test_bit(channel, &st->ch_enable_mask);
+		return 0;
+	default:
+		return -EOPNOTSUPP;
+	}
+	return 0;
+}
+
+static int ltc4283_read_current_word(const struct ltc4283_hwmon *st, u32 reg,
+				     long *val)
+{
+	u64 temp = (u64)LTC4283_ADC1_FS_uV * DECA * MILLI;
+	unsigned int __raw;
+	int ret;
+
+	ret = regmap_read(st->map, reg, &__raw);
+	if (ret)
+		return ret;
+
+	*val = DIV64_U64_ROUND_CLOSEST(__raw * temp,
+				       BIT_ULL(16) * st->rsense);
+
+	return 0;
+}
+
+static int ltc4283_read_current_byte(const struct ltc4283_hwmon *st, u32 reg,
+				     long *val)
+{
+	u64 temp = (u64)LTC4283_ADC1_FS_uV * DECA * MILLI;
+	u32 curr;
+	int ret;
+
+	ret = regmap_read(st->map, reg, &curr);
+	if (ret)
+		return ret;
+
+	*val = DIV_ROUND_CLOSEST_ULL(curr * temp, BIT(8) * st->rsense);
+	return 0;
+}
+
+static int ltc4283_read_curr(struct ltc4283_hwmon *st, u32 attr, long *val)
+{
+	switch (attr) {
+	case hwmon_curr_input:
+		return ltc4283_read_current_word(st, LTC4283_SENSE, val);
+	case hwmon_curr_highest:
+		return ltc4283_read_current_word(st, LTC4283_SENSE_MAX, val);
+	case hwmon_curr_lowest:
+		return ltc4283_read_current_word(st, LTC4283_SENSE_MIN, val);
+	case hwmon_curr_max:
+		return ltc4283_read_current_byte(st, LTC4283_SENSE_MAX_TH, val);
+	case hwmon_curr_min:
+		return ltc4283_read_current_byte(st, LTC4283_SENSE_MIN_TH, val);
+	case hwmon_curr_max_alarm:
+		return ltc4283_read_alarm(st, LTC4283_ADC_ALM_LOG_1,
+					  LTC4283_SENSE_HIGH_ALM, val);
+	case hwmon_curr_min_alarm:
+		return ltc4283_read_alarm(st, LTC4283_ADC_ALM_LOG_1,
+					  LTC4283_SENSE_LOW_ALM, val);
+	case hwmon_curr_crit_alarm:
+		return ltc4283_read_alarm(st, LTC4283_FAULT_STATUS,
+					  LTC4283_OC_MASK, val);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int ltc4283_read_power_word(const struct ltc4283_hwmon *st,
+				   u32 reg, long *val)
+{
+	u64 temp = (u64)LTC4283_ADC1_FS_uV * LTC4283_ADC2_FS_mV * DECA * MILLI;
+	unsigned int __raw;
+	int ret;
+
+	ret = regmap_read(st->map, reg, &__raw);
+	if (ret)
+		return ret;
+
+	/*
+	 * Power is given by:
+	 *     P = CODE(16b) * 32.768mV * 2.048V / (2^16 * Rsense)
+	 */
+	*val = DIV64_U64_ROUND_CLOSEST(temp * __raw, BIT_ULL(16) * st->rsense);
+
+	return 0;
+}
+
+static int ltc4283_read_power_byte(const struct ltc4283_hwmon *st,
+				   u32 reg, long *val)
+{
+	u64 temp = (u64)LTC4283_ADC1_FS_uV * LTC4283_ADC2_FS_mV * DECA * MILLI;
+	u32 power;
+	int ret;
+
+	ret = regmap_read(st->map, reg, &power);
+	if (ret)
+		return ret;
+
+	*val = DIV_ROUND_CLOSEST_ULL(power * temp, BIT(8) * st->rsense);
+
+	return 0;
+}
+
+static int ltc4283_read_power(struct ltc4283_hwmon *st, u32 attr, long *val)
+{
+	switch (attr) {
+	case hwmon_power_input:
+		return ltc4283_read_power_word(st, LTC4283_POWER, val);
+	case hwmon_power_input_highest:
+		return ltc4283_read_power_word(st, LTC4283_POWER_MAX, val);
+	case hwmon_power_input_lowest:
+		return ltc4283_read_power_word(st, LTC4283_POWER_MIN, val);
+	case hwmon_power_max_alarm:
+		return ltc4283_read_alarm(st, LTC4283_ADC_ALM_LOG_1,
+					  LTC4283_POWER_HIGH_ALM, val);
+	case hwmon_power_min_alarm:
+		return ltc4283_read_alarm(st, LTC4283_ADC_ALM_LOG_1,
+					  LTC4283_POWER_LOW_ALM, val);
+	case hwmon_power_max:
+		return ltc4283_read_power_byte(st, LTC4283_POWER_MAX_TH, val);
+	case hwmon_power_min:
+		return ltc4283_read_power_byte(st, LTC4283_POWER_MIN_TH, val);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int ltc4283_read_energy(struct ltc4283_hwmon *st, u32 attr, s64 *val)
+{
+	u64 temp = LTC4283_ADC1_FS_uV * LTC4283_ADC2_FS_mV, energy;
+	u8 raw[8] = {};
+	int ret;
+
+	if (!st->energy_en)
+		return -ENODATA;
+
+	ret = i2c_smbus_read_i2c_block_data(st->client, LTC4283_ENERGY, 6, raw);
+	if (ret < 0)
+		return ret;
+	if (ret != 6)
+		return -EIO;
+
+	energy = get_unaligned_be64(raw) >> 16;
+
+	/*
+	 * The formula for energy is given by:
+	 *	E = CODE(48b) * 32.768mV * 2.048V * Tconv / 2^24 * Rsense
+	 *
+	 * As Rsense can have tenths of micro-ohm resolution, we need to
+	 * multiply by DECA to get microjoule.
+	 */
+
+	/*
+	 * Use mul_u64_u64_div_u64() to handle the 128-bit intermediate
+	 * product of energy (up to 48 bits) * temp * Tconv without overflow.
+	 * Multiply rsense by CENTI to convert from tenths-of-microohm back
+	 * to nanoohm so the result comes out in microjoule.
+	 */
+	energy = mul_u64_u64_div_u64(energy, temp * LTC4283_TCONV_uS,
+				     BIT_ULL(24) * st->rsense * CENTI);
+
+	*val = energy;
+	return 0;
+}
+
+static int ltc4283_read(struct device *dev, enum hwmon_sensor_types type,
+			u32 attr, int channel, long *val)
+{
+	struct ltc4283_hwmon *st = dev_get_drvdata(dev);
+
+	switch (type) {
+	case hwmon_in:
+		return ltc4283_read_in(st, attr, channel, val);
+	case hwmon_curr:
+		return ltc4283_read_curr(st, attr, val);
+	case hwmon_power:
+		return ltc4283_read_power(st, attr, val);
+	case hwmon_energy:
+		*val = st->energy_en;
+		return 0;
+	case hwmon_energy64:
+		return ltc4283_read_energy(st, attr, (s64 *)val);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int ltc4283_write_power_byte(const struct ltc4283_hwmon *st, u32 reg,
+				    long val)
+{
+	u64 temp = (u64)LTC4283_ADC1_FS_uV * LTC4283_ADC2_FS_mV * DECA * MILLI;
+	u32 __raw;
+
+	val = clamp_val(val, 0, st->power_max);
+	__raw = DIV64_U64_ROUND_CLOSEST(val * BIT_ULL(8) * st->rsense, temp);
+
+	return regmap_write(st->map, reg, __raw);
+}
+
+static int ltc4283_write_power_word(const struct ltc4283_hwmon *st,
+				    u32 reg, unsigned long val)
+{
+	u64 divisor = (u64)LTC4283_ADC1_FS_uV * LTC4283_ADC2_FS_mV * DECA * MILLI;
+	u16 __raw;
+
+	__raw = mul_u64_u64_div_u64(val, st->rsense * BIT_ULL(16), divisor);
+
+	return regmap_write(st->map, reg, __raw);
+}
+
+static int ltc4283_reset_power_hist(struct ltc4283_hwmon *st)
+{
+	int ret;
+
+	ret = ltc4283_write_power_word(st, LTC4283_POWER_MIN, st->power_max);
+	if (ret)
+		return ret;
+
+	ret = ltc4283_write_power_word(st, LTC4283_POWER_MAX, 0);
+	if (ret)
+		return ret;
+
+	/* Clear possible power faults. */
+	return regmap_clear_bits(st->map, LTC4283_FAULT_LOG,
+				 LTC4283_PWR_FAIL_FAULT_MASK | LTC4283_PGI_FAULT_MASK);
+}
+
+static int ltc4283_write_power(struct ltc4283_hwmon *st, u32 attr, long val)
+{
+	switch (attr) {
+	case hwmon_power_max:
+		return ltc4283_write_power_byte(st, LTC4283_POWER_MAX_TH, val);
+	case hwmon_power_min:
+		return ltc4283_write_power_byte(st, LTC4283_POWER_MIN_TH, val);
+	case hwmon_power_reset_history:
+		return ltc4283_reset_power_hist(st);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int ltc4283_write_in_history(struct ltc4283_hwmon *st, u32 reg,
+				    long lowest, u32 fs)
+{
+	u32 __raw;
+	int ret;
+
+	__raw = DIV_ROUND_CLOSEST(BIT(16) * lowest, fs);
+	if (__raw == BIT(16))
+		__raw = U16_MAX;
+
+	ret = regmap_write(st->map, reg, __raw);
+	if (ret)
+		return ret;
+
+	return regmap_write(st->map, reg + 1, 0);
+}
+
+static int ltc4283_write_in_byte(const struct ltc4283_hwmon *st,
+				 u32 reg, u32 fs, long val)
+{
+	u32 __raw;
+
+	val = clamp_val(val, 0, fs);
+	__raw = DIV_ROUND_CLOSEST(val * BIT(8), fs);
+	if (__raw == BIT(8))
+		__raw = U8_MAX;
+
+	return regmap_write(st->map, reg, __raw);
+}
+
+static int ltc4283_reset_in_hist(struct ltc4283_hwmon *st, u32 channel)
+{
+	u32 reg, fs;
+	int ret;
+
+	/*
+	 * Make sure to clear possible under/over voltage faults. Otherwise the
+	 * chip won't latch on again.
+	 */
+	if (channel == LTC4283_CHAN_VIN)
+		return regmap_clear_bits(st->map, LTC4283_FAULT_LOG,
+					 LTC4283_OV_FAULT_MASK | LTC4283_UV_FAULT_MASK);
+
+	if (channel == LTC4283_CHAN_VPWR)
+		return ltc4283_write_in_history(st, LTC4283_VPWR_MIN,
+						LTC4283_ADC2_FS_mV,
+						LTC4283_ADC2_FS_mV);
+
+	if (channel >= LTC4283_CHAN_ADI_1 && channel <= LTC4283_CHAN_DRAIN) {
+		fs = LTC4283_ADC2_FS_mV;
+		reg = LTC4283_ADC_2_MIN(channel - LTC4283_CHAN_ADI_1);
+	} else {
+		fs = LTC4283_ADC1_FS_uV;
+		reg = LTC4283_ADC_2_MIN_DIFF(channel - LTC4283_CHAN_ADIN12);
+	}
+
+	ret = ltc4283_write_in_history(st, reg, fs, fs);
+	if (ret)
+		return ret;
+	if (channel != LTC4283_CHAN_DRAIN)
+		return 0;
+
+	/* Then, let's also clear possible fet faults. Same as above. */
+	return regmap_clear_bits(st->map, LTC4283_FAULT_LOG,
+				 LTC4283_FET_BAD_FAULT_MASK | LTC4283_FET_SHORT_FAULT_MASK);
+}
+
+static int ltc4283_write_in_en(struct ltc4283_hwmon *st, u32 channel, bool en)
+{
+	unsigned int bit, adc_idx = channel - LTC4283_CHAN_ADI_1;
+	unsigned int reg = LTC4283_ADC_SELECT(adc_idx);
+	int ret;
+
+	bit = LTC4283_ADC_SELECT_MASK(adc_idx);
+	if (channel > LTC4283_CHAN_DRAIN)
+		/* Account for two reserved fields after DRAIN. */
+		bit <<= 2;
+
+	if (en)
+		ret = regmap_set_bits(st->map, reg, bit);
+	else
+		ret = regmap_clear_bits(st->map, reg, bit);
+	if (ret)
+		return ret;
+
+	__assign_bit(channel, &st->ch_enable_mask, en);
+	return 0;
+}
+
+static int ltc4283_write_minmax(struct ltc4283_hwmon *st, long val,
+				u32 channel, bool is_max)
+{
+	u32 reg;
+
+	if (channel == LTC4283_CHAN_VPWR) {
+		if (is_max)
+			return ltc4283_write_in_byte(st, LTC4283_VPWR_MAX_TH,
+						     LTC4283_ADC2_FS_mV, val);
+
+		return ltc4283_write_in_byte(st, LTC4283_VPWR_MIN_TH,
+					     LTC4283_ADC2_FS_mV, val);
+	}
+
+	if (channel >= LTC4283_CHAN_ADI_1 && channel <= LTC4283_CHAN_DRAIN) {
+		if (is_max) {
+			reg = LTC4283_ADC_2_MAX_TH(channel - LTC4283_CHAN_ADI_1);
+			return ltc4283_write_in_byte(st, reg,
+						     LTC4283_ADC2_FS_mV, val);
+		}
+
+		reg = LTC4283_ADC_2_MIN_TH(channel - LTC4283_CHAN_ADI_1);
+		return ltc4283_write_in_byte(st, reg, LTC4283_ADC2_FS_mV, val);
+	}
+
+	/* Clamp before multiplying to avoid overflow on any arch. */
+	val = clamp_val(val, 0, LONG_MAX / MILLI);
+
+	if (is_max) {
+		reg = LTC4283_ADC_2_MAX_TH_DIFF(channel - LTC4283_CHAN_ADIN12);
+		return ltc4283_write_in_byte(st, reg, LTC4283_ADC1_FS_uV,
+					     val * MILLI);
+	}
+
+	reg = LTC4283_ADC_2_MIN_TH_DIFF(channel - LTC4283_CHAN_ADIN12);
+	return ltc4283_write_in_byte(st, reg, LTC4283_ADC1_FS_uV, val * MILLI);
+}
+
+static int ltc4283_write_in(struct ltc4283_hwmon *st, u32 attr, long val,
+			    int channel)
+{
+	switch (attr) {
+	case hwmon_in_max:
+		return ltc4283_write_minmax(st, val, channel, true);
+	case hwmon_in_min:
+		return ltc4283_write_minmax(st, val, channel, false);
+	case hwmon_in_reset_history:
+		return ltc4283_reset_in_hist(st, channel);
+	case hwmon_in_enable:
+		return ltc4283_write_in_en(st, channel, !!val);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int ltc4283_write_curr_byte(const struct ltc4283_hwmon *st,
+				   u32 reg, long val)
+{
+	u32 temp = LTC4283_ADC1_FS_uV * DECA * MILLI;
+	u32 reg_val, isense_max;
+
+	isense_max = DIV_ROUND_CLOSEST(st->vsense_max * MICRO * DECA, st->rsense);
+	val = clamp_val(val, 0, isense_max);
+	reg_val = DIV_ROUND_CLOSEST_ULL(val * BIT_ULL(8) * st->rsense, temp);
+
+	return regmap_write(st->map, reg, reg_val);
+}
+
+static int ltc4283_write_curr_history(struct ltc4283_hwmon *st)
+{
+	int ret;
+
+	ret = ltc4283_write_in_history(st, LTC4283_SENSE_MIN,
+				       st->vsense_max * MILLI,
+				       LTC4283_ADC1_FS_uV);
+	if (ret)
+		return ret;
+
+	/* Now, let's also clear possible overcurrent logs. */
+	return regmap_clear_bits(st->map, LTC4283_FAULT_LOG,
+				 LTC4283_OC_FAULT_MASK);
+}
+
+static int ltc4283_write_curr(struct ltc4283_hwmon *st, u32 attr, long val)
+{
+	switch (attr) {
+	case hwmon_curr_max:
+		return ltc4283_write_curr_byte(st, LTC4283_SENSE_MAX_TH, val);
+	case hwmon_curr_min:
+		return ltc4283_write_curr_byte(st, LTC4283_SENSE_MIN_TH, val);
+	case hwmon_curr_reset_history:
+		return ltc4283_write_curr_history(st);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int ltc4283_energy_enable_set(struct ltc4283_hwmon *st, long val)
+{
+	int ret;
+
+	/* Setting the bit halts the meter. */
+	val = !!val;
+	ret = regmap_update_bits(st->map, LTC4283_METER_CONTROL,
+				 LTC4283_METER_HALT_MASK,
+				 FIELD_PREP(LTC4283_METER_HALT_MASK, !val));
+	if (ret)
+		return ret;
+
+	st->energy_en = val;
+
+	return 0;
+}
+
+static int ltc4283_write(struct device *dev, enum hwmon_sensor_types type,
+			 u32 attr, int channel, long val)
+{
+	struct ltc4283_hwmon *st = dev_get_drvdata(dev);
+
+	switch (type) {
+	case hwmon_power:
+		return ltc4283_write_power(st, attr, val);
+	case hwmon_in:
+		return ltc4283_write_in(st, attr, val, channel);
+	case hwmon_curr:
+		return ltc4283_write_curr(st, attr, val);
+	case hwmon_energy:
+		return ltc4283_energy_enable_set(st, val);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static umode_t ltc4283_in_is_visible(const struct ltc4283_hwmon *st,
+				     u32 attr, int channel)
+{
+	/* If ADIO is set as a GPIO, don´t make it visible. */
+	if (channel >= LTC4283_CHAN_ADIO_1 && channel <= LTC4283_CHAN_ADIO_4) {
+		/* ADIOX pins come at index 0 in the gpio mask. */
+		channel -= LTC4283_CHAN_ADIO_1;
+		if (test_bit(channel, &st->gpio_mask))
+			return 0;
+	}
+
+	/* Also take care of differential channels. */
+	if (channel >= LTC4283_CHAN_ADIO12 && channel <= LTC4283_CHAN_ADIO34) {
+		channel -= LTC4283_CHAN_ADIO12;
+		/* If one channel in the pair is used, make it invisible. */
+		if (test_bit(channel * 2, &st->gpio_mask) ||
+		    test_bit(channel * 2 + 1, &st->gpio_mask))
+			return 0;
+	}
+
+	switch (attr) {
+	case hwmon_in_input:
+	case hwmon_in_highest:
+	case hwmon_in_lowest:
+	case hwmon_in_max_alarm:
+	case hwmon_in_min_alarm:
+	case hwmon_in_label:
+	case hwmon_in_lcrit_alarm:
+	case hwmon_in_crit_alarm:
+	case hwmon_in_fault:
+		return 0444;
+	case hwmon_in_max:
+	case hwmon_in_min:
+	case hwmon_in_enable:
+		return 0644;
+	case hwmon_in_reset_history:
+		return 0200;
+	default:
+		return 0;
+	}
+}
+
+static umode_t ltc4283_curr_is_visible(u32 attr)
+{
+	switch (attr) {
+	case hwmon_curr_input:
+	case hwmon_curr_highest:
+	case hwmon_curr_lowest:
+	case hwmon_curr_max_alarm:
+	case hwmon_curr_min_alarm:
+	case hwmon_curr_crit_alarm:
+	case hwmon_curr_label:
+		return 0444;
+	case hwmon_curr_max:
+	case hwmon_curr_min:
+		return 0644;
+	case hwmon_curr_reset_history:
+		return 0200;
+	default:
+		return 0;
+	}
+}
+
+static umode_t ltc4283_power_is_visible(u32 attr)
+{
+	switch (attr) {
+	case hwmon_power_input:
+	case hwmon_power_input_highest:
+	case hwmon_power_input_lowest:
+	case hwmon_power_label:
+	case hwmon_power_max_alarm:
+	case hwmon_power_min_alarm:
+		return 0444;
+	case hwmon_power_max:
+	case hwmon_power_min:
+		return 0644;
+	case hwmon_power_reset_history:
+		return 0200;
+	default:
+		return 0;
+	}
+}
+
+static umode_t ltc4283_is_visible(const void *data,
+				  enum hwmon_sensor_types type,
+				  u32 attr, int channel)
+{
+	switch (type) {
+	case hwmon_in:
+		return ltc4283_in_is_visible(data, attr, channel);
+	case hwmon_curr:
+		return ltc4283_curr_is_visible(attr);
+	case hwmon_power:
+		return ltc4283_power_is_visible(attr);
+	case hwmon_energy:
+		/* hwmon_energy_enable */
+		return 0644;
+	case hwmon_energy64:
+		/* hwmon_energy_input */
+		return 0444;
+	default:
+		return 0;
+	}
+}
+
+static const char * const ltc4283_in_strs[] = {
+	"VIN", "VPWR", "VADI1", "VADI2", "VADI3", "VADI4", "VADIO1", "VADIO2",
+	"VADIO3", "VADIO4", "DRNS", "DRAIN", "ADIN2-ADIN1", "ADIN4-ADIN3",
+	"ADIO2-ADIO1", "ADIO4-ADIO3"
+};
+
+static int ltc4283_read_labels(struct device *dev,
+			       enum hwmon_sensor_types type,
+			       u32 attr, int channel, const char **str)
+{
+	switch (type) {
+	case hwmon_in:
+		*str = ltc4283_in_strs[channel];
+		return 0;
+	case hwmon_curr:
+		*str = "ISENSE";
+		return 0;
+	case hwmon_power:
+		*str = "Power";
+		return 0;
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+/*
+ * Set max limits for ISENSE and Power as that depends on the max voltage on
+ * rsense that is defined in ILIM_ADJUST. This is specially important for power
+ * because for some rsense and vfsout values, if we allow the default raw 255
+ * value, that would overflow long in 32bit archs when reading back the max
+ * power limit.
+ */
+static int ltc4283_set_max_limits(struct ltc4283_hwmon *st, struct device *dev)
+{
+	u32 temp = st->vsense_max * DECA * MICRO;
+	int ret;
+
+	ret = ltc4283_write_in_byte(st, LTC4283_SENSE_MAX_TH, LTC4283_ADC1_FS_uV,
+				    st->vsense_max * MILLI);
+	if (ret)
+		return ret;
+
+	/* Power is given by ISENSE * Vout. */
+	st->power_max = DIV_ROUND_CLOSEST(temp, st->rsense) * LTC4283_ADC2_FS_mV;
+	return ltc4283_write_power_byte(st, LTC4283_POWER_MAX_TH, st->power_max);
+}
+
+static int ltc4283_parse_array_prop(const struct ltc4283_hwmon *st,
+				    struct device *dev, const char *prop,
+				    const u32 *vals, u32 n_vals)
+{
+	u32 prop_val;
+	int ret;
+	u32 i;
+
+	ret = device_property_read_u32(dev, prop, &prop_val);
+	if (ret)
+		return n_vals;
+
+	for (i = 0; i < n_vals; i++) {
+		if (prop_val != vals[i])
+			continue;
+
+		return i;
+	}
+
+	return dev_err_probe(dev, -EINVAL,
+			     "Invalid %s property value %u\n", prop, prop_val);
+}
+
+static int ltc4283_get_defaults(struct ltc4283_hwmon *st)
+{
+	u32 reg_val, ilm_adjust, c;
+	int ret;
+
+	ret = regmap_read(st->map, LTC4283_METER_CONTROL, &reg_val);
+	if (ret)
+		return ret;
+
+	st->energy_en = !FIELD_GET(LTC4283_METER_HALT_MASK, reg_val);
+
+	ret = regmap_read(st->map, LTC4283_CONFIG_1, &reg_val);
+	if (ret)
+		return ret;
+
+	ilm_adjust = FIELD_GET(LTC4283_ILIM_MASK, reg_val);
+	st->vsense_max = LTC4283_VILIM_MIN_uV / MILLI + ilm_adjust;
+
+	ret = regmap_read(st->map, LTC4283_PGIO_CONFIG, &reg_val);
+	if (ret)
+		return ret;
+
+	/* Can be latter overwritten in ltc4283_pgio_config() */
+	if (FIELD_GET(LTC4283_PGIO4_CFG_MASK, reg_val) < LTC4283_PGIO_FUNC_GPIO)
+		st->ext_fault = true;
+
+	/* VPWR and VIN are always enabled */
+	__set_bit(LTC4283_CHAN_VIN, &st->ch_enable_mask);
+	__set_bit(LTC4283_CHAN_VPWR, &st->ch_enable_mask);
+	for (c = LTC4283_CHAN_ADI_1; c < LTC4283_CHAN_MAX; c++) {
+		u32 chan = c - LTC4283_CHAN_ADI_1, bit;
+
+		ret = regmap_read(st->map, LTC4283_ADC_SELECT(chan), &reg_val);
+		if (ret)
+			return ret;
+
+		bit = LTC4283_ADC_SELECT_MASK(chan);
+		if (c > LTC4283_CHAN_DRAIN)
+			/* account for two reserved fields after DRAIN */
+			bit <<= 2;
+
+		if (!(bit & reg_val))
+			continue;
+
+		__set_bit(c, &st->ch_enable_mask);
+	}
+
+	return 0;
+}
+
+static const char * const ltc4283_pgio1_funcs[] = {
+	"inverted_power_good", "power_good", "gpio"
+};
+
+static const char * const ltc4283_pgio2_funcs[] = {
+	 "inverted_power_good", "power_good", "gpio", "active_current_limiting"
+};
+
+static const char * const ltc4283_pgio3_funcs[] = {
+	"inverted_power_good_input", "power_good_input", "gpio"
+};
+
+static const char * const ltc4283_pgio4_funcs[] = {
+	"inverted_external_fault", "external_fault", "gpio"
+};
+
+enum {
+	LTC4283_PIN_ADIO1,
+	LTC4283_PIN_ADIO2,
+	LTC4283_PIN_ADIO3,
+	LTC4283_PIN_ADIO4,
+	LTC4283_PIN_PGIO1,
+	LTC4283_PIN_PGIO2,
+	LTC4283_PIN_PGIO3,
+	LTC4283_PIN_PGIO4,
+};
+
+static int ltc4283_pgio_config(struct ltc4283_hwmon *st, struct device *dev)
+{
+	int ret, func;
+
+	func = device_property_match_property_string(dev, "adi,pgio1-func",
+						     ltc4283_pgio1_funcs,
+						     ARRAY_SIZE(ltc4283_pgio1_funcs));
+	if (func < 0 && func != -EINVAL)
+		return dev_err_probe(dev, func,
+				     "Invalid adi,pgio1-func property\n");
+	if (func >= 0) {
+		if (func == LTC4283_PGIO_FUNC_GPIO) {
+			__set_bit(LTC4283_PIN_PGIO1, &st->gpio_mask);
+			/* If GPIO, default to an input pin. */
+			func++;
+		}
+
+		ret = regmap_update_bits(st->map, LTC4283_PGIO_CONFIG,
+					 LTC4283_PGIO1_CFG_MASK,
+					 FIELD_PREP(LTC4283_PGIO1_CFG_MASK, func));
+		if (ret)
+			return ret;
+	}
+
+	func = device_property_match_property_string(dev, "adi,pgio2-func",
+						     ltc4283_pgio2_funcs,
+						     ARRAY_SIZE(ltc4283_pgio2_funcs));
+
+	if (func < 0 && func != -EINVAL)
+		return dev_err_probe(dev, func,
+				     "Invalid adi,pgio2-func property\n");
+	if (func >= 0) {
+		if (func != LTC4283_PGIO2_FUNC_ACLB) {
+			if (func == LTC4283_PGIO_FUNC_GPIO)  {
+				__set_bit(LTC4283_PIN_PGIO2, &st->gpio_mask);
+				func++;
+			}
+
+			ret = regmap_update_bits(st->map, LTC4283_PGIO_CONFIG,
+						 LTC4283_PGIO2_CFG_MASK,
+						 FIELD_PREP(LTC4283_PGIO2_CFG_MASK, func));
+		} else {
+			ret = regmap_set_bits(st->map, LTC4283_CONTROL_1,
+					      LTC4283_PIGIO2_ACLB_MASK);
+		}
+
+		if (ret)
+			return ret;
+	}
+
+	func = device_property_match_property_string(dev, "adi,pgio3-func",
+						     ltc4283_pgio3_funcs,
+						     ARRAY_SIZE(ltc4283_pgio3_funcs));
+
+	if (func < 0 && func != -EINVAL)
+		return dev_err_probe(dev, func,
+				     "Invalid adi,pgio3-func property\n");
+	if (func >= 0) {
+		if (func == LTC4283_PGIO_FUNC_GPIO) {
+			__set_bit(LTC4283_PIN_PGIO3, &st->gpio_mask);
+			func++;
+		}
+
+		ret = regmap_update_bits(st->map, LTC4283_PGIO_CONFIG,
+					 LTC4283_PGIO3_CFG_MASK,
+					 FIELD_PREP(LTC4283_PGIO3_CFG_MASK, func));
+		if (ret)
+			return ret;
+	}
+
+	func = device_property_match_property_string(dev, "adi,pgio4-func",
+						     ltc4283_pgio4_funcs,
+						     ARRAY_SIZE(ltc4283_pgio4_funcs));
+
+	if (func < 0 && func != -EINVAL)
+		return dev_err_probe(dev, func,
+				     "Invalid adi,pgio4-func property\n");
+	if (func >= 0) {
+		if (func == LTC4283_PGIO_FUNC_GPIO) {
+			__set_bit(LTC4283_PIN_PGIO4, &st->gpio_mask);
+			func++;
+			st->ext_fault = false;
+		} else {
+			st->ext_fault = true;
+		}
+
+		ret = regmap_update_bits(st->map, LTC4283_PGIO_CONFIG,
+					 LTC4283_PGIO4_CFG_MASK,
+					 FIELD_PREP(LTC4283_PGIO4_CFG_MASK, func));
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static int ltc4283_adio_config(struct ltc4283_hwmon *st, struct device *dev,
+			       const char *prop, u32 pin)
+{
+	u32 adc_idx;
+	int ret;
+
+	if (!device_property_read_bool(dev, prop))
+		return 0;
+
+	adc_idx = LTC4283_CHAN_ADIO_1 - LTC4283_CHAN_ADI_1 + pin;
+	ret = regmap_clear_bits(st->map, LTC4283_ADC_SELECT(adc_idx),
+				LTC4283_ADC_SELECT_MASK(adc_idx));
+	if (ret)
+		return ret;
+
+	__set_bit(pin, &st->gpio_mask);
+	return 0;
+}
+
+static int ltc4283_pin_config(struct ltc4283_hwmon *st, struct device *dev)
+{
+	int ret;
+
+	ret = ltc4283_pgio_config(st, dev);
+	if (ret)
+		return ret;
+
+	ret = ltc4283_adio_config(st, dev, "adi,gpio-on-adio1", LTC4283_PIN_ADIO1);
+	if (ret)
+		return ret;
+
+	ret = ltc4283_adio_config(st, dev, "adi,gpio-on-adio2", LTC4283_PIN_ADIO2);
+	if (ret)
+		return ret;
+
+	ret = ltc4283_adio_config(st, dev, "adi,gpio-on-adio3", LTC4283_PIN_ADIO3);
+	if (ret)
+		return ret;
+
+	return ltc4283_adio_config(st, dev, "adi,gpio-on-adio4", LTC4283_PIN_ADIO4);
+}
+
+static const char * const ltc4283_oc_fet_retry[] = {
+	"latch-off", "1", "7", "unlimited"
+};
+
+static const u32 ltc4283_fb_factor[] = {
+	100, 50, 20, 10
+};
+
+static const u32 ltc4283_cooling_dl[] = {
+	512, 1002, 2005, 4100, 8190, 16400, 32800, 65600
+};
+
+static const u32 ltc4283_fet_bad_delay[] = {
+	256, 512, 1002, 2005
+};
+
+static int ltc4283_setup(struct ltc4283_hwmon *st, struct device *dev)
+{
+	u32 val;
+	int ret;
+
+	/* The part has an eeprom so let's get the needed defaults from it */
+	ret = ltc4283_get_defaults(st);
+	if (ret)
+		return ret;
+
+	/*
+	 * Default to LTC4283_MIN_RSENSE so we can probe without FW properties.
+	 */
+	st->rsense = LTC4283_MIN_RSENSE;
+	ret = device_property_read_u32(dev, "adi,rsense-nano-ohms",
+				       &st->rsense);
+	if (!ret) {
+		if (st->rsense < LTC4283_MIN_RSENSE || st->rsense > LTC4283_MAX_RSENSE)
+			return dev_err_probe(dev, -EINVAL,
+					     "adi,rsense-nano-ohms(%u) too small or too large [%u %u]\n",
+					     st->rsense, LTC4283_MIN_RSENSE, LTC4283_MAX_RSENSE);
+	}
+
+	/*
+	 * The resolution for rsense is tenths of micro (eg: 62.5 uOhm) which
+	 * means we need nano in the bindings. However, to make things easier to
+	 * handle (with respect to overflows) we divide it by 100 as we don't
+	 * really need the last two digits.
+	 */
+	st->rsense /= CENTI;
+
+	ret = device_property_read_u32(dev, "adi,current-limit-sense-microvolt",
+				       &st->vsense_max);
+	if (!ret) {
+		u32 reg_val;
+
+		if (!in_range(st->vsense_max, LTC4283_VILIM_MIN_uV,
+			      LTC4283_VILIM_RANGE)) {
+			return dev_err_probe(dev, -EINVAL,
+					     "adi,current-limit-sense-microvolt (%u) out of range [%u %u]\n",
+					     st->vsense_max, LTC4283_VILIM_MIN_uV,
+					     LTC4283_VILIM_MAX_uV);
+		}
+
+		st->vsense_max /= MILLI;
+		reg_val = FIELD_PREP(LTC4283_ILIM_MASK,
+				     st->vsense_max - LTC4283_VILIM_MIN_uV / MILLI);
+		ret = regmap_update_bits(st->map, LTC4283_CONFIG_1,
+					 LTC4283_ILIM_MASK, reg_val);
+		if (ret)
+			return ret;
+	}
+
+	ret = ltc4283_parse_array_prop(st, dev, "adi,current-limit-foldback-factor",
+				       ltc4283_fb_factor, ARRAY_SIZE(ltc4283_fb_factor));
+	if (ret < 0)
+		return ret;
+	if (ret < ARRAY_SIZE(ltc4283_fb_factor)) {
+		ret = regmap_update_bits(st->map, LTC4283_CONFIG_1, LTC4283_FB_MASK,
+					 FIELD_PREP(LTC4283_FB_MASK, ret));
+		if (ret)
+			return ret;
+	}
+
+	ret = ltc4283_parse_array_prop(st, dev, "adi,cooling-delay-ms",
+				       ltc4283_cooling_dl, ARRAY_SIZE(ltc4283_cooling_dl));
+	if (ret < 0)
+		return ret;
+	if (ret < ARRAY_SIZE(ltc4283_cooling_dl)) {
+		ret = regmap_update_bits(st->map, LTC4283_CONFIG_2, LTC4283_COOLING_DL_MASK,
+					 FIELD_PREP(LTC4283_COOLING_DL_MASK, ret));
+		if (ret)
+			return ret;
+	}
+
+	ret = ltc4283_parse_array_prop(st, dev, "adi,fet-bad-timer-delay-ms",
+				       ltc4283_fet_bad_delay, ARRAY_SIZE(ltc4283_fet_bad_delay));
+	if (ret < 0)
+		return ret;
+	if (ret < ARRAY_SIZE(ltc4283_fet_bad_delay)) {
+		ret = regmap_update_bits(st->map, LTC4283_CONFIG_2, LTC4283_FTBD_DL_MASK,
+					 FIELD_PREP(LTC4283_FTBD_DL_MASK, ret));
+		if (ret)
+			return ret;
+	}
+
+	ret = ltc4283_set_max_limits(st, dev);
+	if (ret)
+		return ret;
+
+	ret = ltc4283_pin_config(st, dev);
+	if (ret)
+		return ret;
+
+	if (device_property_read_bool(dev, "adi,power-good-reset-on-fet")) {
+		ret = regmap_clear_bits(st->map, LTC4283_CONTROL_1,
+					LTC4283_PWRGD_RST_CTRL_MASK);
+		if (ret)
+			return ret;
+	}
+
+	if (device_property_read_bool(dev, "adi,fet-turn-off-disable")) {
+		ret = regmap_clear_bits(st->map, LTC4283_CONTROL_1,
+					LTC4283_FET_BAD_OFF_MASK);
+		if (ret)
+			return ret;
+	}
+
+	if (device_property_read_bool(dev, "adi,tmr-pull-down-disable")) {
+		ret = regmap_set_bits(st->map, LTC4283_CONTROL_1,
+				      LTC4283_THERM_TMR_MASK);
+		if (ret)
+			return ret;
+	}
+
+	if (device_property_read_bool(dev, "adi,dvdt-inrush-control-disable")) {
+		ret = regmap_clear_bits(st->map, LTC4283_CONTROL_1,
+					LTC4283_DVDT_MASK);
+		if (ret)
+			return ret;
+	}
+
+	if (device_property_read_bool(dev, "adi,undervoltage-retry-disable")) {
+		ret = regmap_clear_bits(st->map, LTC4283_CONTROL_2,
+					LTC4283_UV_RETRY_MASK);
+		if (ret)
+			return ret;
+	}
+
+	if (device_property_read_bool(dev, "adi,overvoltage-retry-disable")) {
+		ret = regmap_clear_bits(st->map, LTC4283_CONTROL_2,
+					LTC4283_OV_RETRY_MASK);
+		if (ret)
+			return ret;
+	}
+
+	if (device_property_read_bool(dev, "adi,external-fault-retry-enable")) {
+		if (!st->ext_fault)
+			return dev_err_probe(dev, -EINVAL,
+					     "adi,external-fault-retry-enable set but PGIO4 not configured\n");
+		ret = regmap_set_bits(st->map, LTC4283_CONTROL_2,
+				      LTC4283_EXT_FAULT_RETRY_MASK);
+		if (ret)
+			return ret;
+	}
+
+	if (device_property_read_bool(dev, "adi,fault-log-enable")) {
+		ret = regmap_set_bits(st->map, LTC4283_FAULT_LOG_CTRL,
+				      LTC4283_FAULT_LOG_EN_MASK);
+		if (ret)
+			return ret;
+	}
+
+	ret = device_property_match_property_string(dev, "adi,overcurrent-retries",
+						    ltc4283_oc_fet_retry,
+						    ARRAY_SIZE(ltc4283_oc_fet_retry));
+	/* We still want to catch when an invalid string is given. */
+	if (ret < 0 && ret != -EINVAL)
+		return dev_err_probe(dev, ret,
+				     "adi,overcurrent-retries invalid value\n");
+	if (ret >= 0) {
+		ret = regmap_update_bits(st->map, LTC4283_CONTROL_2,
+					 LTC4283_OC_RETRY_MASK,
+					 FIELD_PREP(LTC4283_OC_RETRY_MASK, ret));
+		if (ret)
+			return ret;
+	}
+
+	ret = device_property_match_property_string(dev, "adi,fet-bad-retries",
+						    ltc4283_oc_fet_retry,
+						    ARRAY_SIZE(ltc4283_oc_fet_retry));
+	if (ret < 0 && ret != -EINVAL)
+		return dev_err_probe(dev, ret,
+				     "adi,fet-bad-retries invalid value\n");
+	if (ret >= 0) {
+		ret = regmap_update_bits(st->map, LTC4283_CONTROL_2,
+					 LTC4283_FET_BAD_RETRY_MASK,
+					 FIELD_PREP(LTC4283_FET_BAD_RETRY_MASK, ret));
+		if (ret)
+			return ret;
+	}
+
+	if (device_property_read_bool(dev, "adi,external-fault-fet-off-enable")) {
+		if (!st->ext_fault)
+			return dev_err_probe(dev, -EINVAL,
+					     "adi,external-fault-fet-off-enable set but PGIO4 not configured\n");
+		ret = regmap_set_bits(st->map, LTC4283_CONFIG_3,
+				      LTC4283_EXTFLT_TURN_OFF_MASK);
+		if (ret)
+			return ret;
+	}
+
+	if (device_property_read_bool(dev, "adi,vpower-drns-enable")) {
+		u32 chan = LTC4283_CHAN_DRNS - LTC4283_CHAN_ADI_1;
+
+		__clear_bit(LTC4283_CHAN_DRNS, &st->ch_enable_mask);
+		/*
+		 * Then, let's by default disable DRNS from ADC2 given that it
+		 * is already being monitored by the VPWR channel. One can still
+		 * enable it later on if needed.
+		 */
+		ret = regmap_clear_bits(st->map, LTC4283_ADC_SELECT(chan),
+					LTC4283_ADC_SELECT_MASK(chan));
+		if (ret)
+			return ret;
+
+		val = 1;
+	} else {
+		val = 0;
+	}
+
+	ret = regmap_update_bits(st->map, LTC4283_CONFIG_3,
+				 LTC4283_VPWR_DRNS_MASK,
+				 FIELD_PREP(LTC4283_VPWR_DRNS_MASK, val));
+	if (ret)
+		return ret;
+
+	/* Make sure the ADC has 12bit resolution since we're assuming that. */
+	ret = regmap_update_bits(st->map, LTC4283_PGIO_CONFIG_2,
+				 LTC4283_ADC_MASK,
+				 FIELD_PREP(LTC4283_ADC_MASK, 3));
+	if (ret)
+		return ret;
+
+	/* Energy reads (which are 6 byte block reads) rely on page access */
+	ret = regmap_set_bits(st->map, LTC4283_CONTROL_1, LTC4283_RW_PAGE_MASK);
+	if (ret)
+		return ret;
+
+	/*
+	 * Make sure we are integrating power as we only support reporting
+	 * consumed energy.
+	 */
+	return regmap_clear_bits(st->map, LTC4283_METER_CONTROL,
+				 LTC4283_INTEGRATE_I_MASK);
+}
+
+static const struct hwmon_channel_info * const ltc4283_info[] = {
+	HWMON_CHANNEL_INFO(in,
+			   HWMON_I_LCRIT_ALARM | HWMON_I_CRIT_ALARM |
+			   HWMON_I_RESET_HISTORY | HWMON_I_LABEL,
+			   HWMON_I_INPUT | HWMON_I_LOWEST | HWMON_I_HIGHEST |
+			   HWMON_I_MAX | HWMON_I_MIN | HWMON_I_MIN_ALARM |
+			   HWMON_I_MAX_ALARM | HWMON_I_RESET_HISTORY |
+			   HWMON_I_LABEL,
+			   HWMON_I_INPUT | HWMON_I_LOWEST | HWMON_I_HIGHEST |
+			   HWMON_I_MAX | HWMON_I_MIN | HWMON_I_MIN_ALARM |
+			   HWMON_I_RESET_HISTORY | HWMON_I_MAX_ALARM |
+			   HWMON_I_ENABLE | HWMON_I_LABEL,
+			   HWMON_I_INPUT | HWMON_I_LOWEST | HWMON_I_HIGHEST |
+			   HWMON_I_MAX | HWMON_I_MIN | HWMON_I_MIN_ALARM |
+			   HWMON_I_RESET_HISTORY | HWMON_I_MAX_ALARM |
+			   HWMON_I_ENABLE | HWMON_I_LABEL,
+			   HWMON_I_INPUT | HWMON_I_LOWEST | HWMON_I_HIGHEST |
+			   HWMON_I_MAX | HWMON_I_MIN | HWMON_I_MIN_ALARM |
+			   HWMON_I_RESET_HISTORY | HWMON_I_MAX_ALARM |
+			   HWMON_I_ENABLE | HWMON_I_LABEL,
+			   HWMON_I_INPUT | HWMON_I_LOWEST | HWMON_I_HIGHEST |
+			   HWMON_I_MAX | HWMON_I_MIN | HWMON_I_MIN_ALARM |
+			   HWMON_I_RESET_HISTORY | HWMON_I_MAX_ALARM |
+			   HWMON_I_ENABLE | HWMON_I_LABEL,
+			   HWMON_I_INPUT | HWMON_I_LOWEST | HWMON_I_HIGHEST |
+			   HWMON_I_MAX | HWMON_I_MIN | HWMON_I_MIN_ALARM |
+			   HWMON_I_RESET_HISTORY | HWMON_I_MAX_ALARM |
+			   HWMON_I_ENABLE | HWMON_I_LABEL,
+			   HWMON_I_INPUT | HWMON_I_LOWEST | HWMON_I_HIGHEST |
+			   HWMON_I_MAX | HWMON_I_MIN | HWMON_I_MIN_ALARM |
+			   HWMON_I_RESET_HISTORY | HWMON_I_MAX_ALARM |
+			   HWMON_I_ENABLE | HWMON_I_LABEL,
+			   HWMON_I_INPUT | HWMON_I_LOWEST | HWMON_I_HIGHEST |
+			   HWMON_I_MAX | HWMON_I_MIN | HWMON_I_MIN_ALARM |
+			   HWMON_I_RESET_HISTORY | HWMON_I_MAX_ALARM |
+			   HWMON_I_ENABLE | HWMON_I_LABEL,
+			   HWMON_I_INPUT | HWMON_I_LOWEST | HWMON_I_HIGHEST |
+			   HWMON_I_MAX | HWMON_I_MIN | HWMON_I_MIN_ALARM |
+			   HWMON_I_RESET_HISTORY | HWMON_I_MAX_ALARM |
+			   HWMON_I_ENABLE | HWMON_I_LABEL,
+			   HWMON_I_INPUT | HWMON_I_LOWEST | HWMON_I_HIGHEST |
+			   HWMON_I_MAX | HWMON_I_MIN | HWMON_I_MIN_ALARM |
+			   HWMON_I_RESET_HISTORY | HWMON_I_MAX_ALARM |
+			   HWMON_I_ENABLE | HWMON_I_LABEL,
+			   HWMON_I_INPUT | HWMON_I_LOWEST | HWMON_I_HIGHEST |
+			   HWMON_I_MAX | HWMON_I_MIN | HWMON_I_MIN_ALARM |
+			   HWMON_I_RESET_HISTORY | HWMON_I_MAX_ALARM |
+			   HWMON_I_FAULT | HWMON_I_ENABLE | HWMON_I_LABEL,
+			   HWMON_I_INPUT | HWMON_I_LOWEST | HWMON_I_HIGHEST |
+			   HWMON_I_MAX | HWMON_I_MIN | HWMON_I_MIN_ALARM |
+			   HWMON_I_RESET_HISTORY | HWMON_I_MAX_ALARM |
+			   HWMON_I_ENABLE | HWMON_I_LABEL,
+			   HWMON_I_INPUT | HWMON_I_LOWEST | HWMON_I_HIGHEST |
+			   HWMON_I_MAX | HWMON_I_MIN | HWMON_I_MIN_ALARM |
+			   HWMON_I_RESET_HISTORY | HWMON_I_MAX_ALARM |
+			   HWMON_I_ENABLE | HWMON_I_LABEL,
+			   HWMON_I_INPUT | HWMON_I_LOWEST | HWMON_I_HIGHEST |
+			   HWMON_I_MAX | HWMON_I_MIN | HWMON_I_MIN_ALARM |
+			   HWMON_I_RESET_HISTORY | HWMON_I_MAX_ALARM |
+			   HWMON_I_ENABLE | HWMON_I_LABEL,
+			   HWMON_I_INPUT | HWMON_I_LOWEST | HWMON_I_HIGHEST |
+			   HWMON_I_MAX | HWMON_I_MIN | HWMON_I_MIN_ALARM |
+			   HWMON_I_RESET_HISTORY | HWMON_I_MAX_ALARM |
+			   HWMON_I_ENABLE | HWMON_I_LABEL),
+	HWMON_CHANNEL_INFO(curr,
+			   HWMON_C_INPUT | HWMON_C_LOWEST | HWMON_C_HIGHEST |
+			   HWMON_C_MAX | HWMON_C_MIN | HWMON_C_MIN_ALARM |
+			   HWMON_C_MAX_ALARM | HWMON_C_CRIT_ALARM |
+			   HWMON_C_RESET_HISTORY | HWMON_C_LABEL),
+	HWMON_CHANNEL_INFO(power,
+			   HWMON_P_INPUT | HWMON_P_INPUT_LOWEST |
+			   HWMON_P_INPUT_HIGHEST | HWMON_P_MAX | HWMON_P_MIN |
+			   HWMON_P_MAX_ALARM | HWMON_P_MIN_ALARM |
+			   HWMON_P_RESET_HISTORY | HWMON_P_LABEL),
+	HWMON_CHANNEL_INFO(energy,
+			   HWMON_E_ENABLE),
+	HWMON_CHANNEL_INFO(energy64,
+			   HWMON_E_INPUT),
+	NULL
+};
+
+static const struct hwmon_ops ltc4283_ops = {
+	.read = ltc4283_read,
+	.write = ltc4283_write,
+	.is_visible = ltc4283_is_visible,
+	.read_string = ltc4283_read_labels,
+};
+
+static const struct hwmon_chip_info ltc4283_chip_info = {
+	.ops = &ltc4283_ops,
+	.info = ltc4283_info,
+};
+
+static int ltc4283_show_fault_log(void *arg, u64 *val, u32 mask)
+{
+	struct ltc4283_hwmon *st = arg;
+	long alarm;
+	int ret;
+
+	ret = ltc4283_read_alarm(st, LTC4283_FAULT_LOG, mask, &alarm);
+	if (ret)
+		return ret;
+
+	*val = alarm;
+
+	return 0;
+}
+
+static int ltc4283_show_in0_lcrit_fault_log(void *arg, u64 *val)
+{
+	return ltc4283_show_fault_log(arg, val, LTC4283_UV_FAULT_MASK);
+}
+DEFINE_DEBUGFS_ATTRIBUTE(ltc4283_in0_lcrit_fault_log,
+			 ltc4283_show_in0_lcrit_fault_log, NULL, "%llu\n");
+
+static int ltc4283_show_in0_crit_fault_log(void *arg, u64 *val)
+{
+	return ltc4283_show_fault_log(arg, val, LTC4283_OV_FAULT_MASK);
+}
+DEFINE_DEBUGFS_ATTRIBUTE(ltc4283_in0_crit_fault_log,
+			 ltc4283_show_in0_crit_fault_log, NULL, "%llu\n");
+
+static int ltc4283_show_fet_bad_fault_log(void *arg, u64 *val)
+{
+	return ltc4283_show_fault_log(arg, val, LTC4283_FET_BAD_FAULT_MASK);
+}
+DEFINE_DEBUGFS_ATTRIBUTE(ltc4283_fet_bad_fault_log,
+			 ltc4283_show_fet_bad_fault_log, NULL, "%llu\n");
+
+static int ltc4283_show_fet_short_fault_log(void *arg, u64 *val)
+{
+	return ltc4283_show_fault_log(arg, val, LTC4283_FET_SHORT_FAULT_MASK);
+}
+DEFINE_DEBUGFS_ATTRIBUTE(ltc4283_fet_short_fault_log,
+			 ltc4283_show_fet_short_fault_log, NULL, "%llu\n");
+
+static int ltc4283_show_curr1_crit_fault_log(void *arg, u64 *val)
+{
+	return ltc4283_show_fault_log(arg, val, LTC4283_OC_FAULT_MASK);
+}
+DEFINE_DEBUGFS_ATTRIBUTE(ltc4283_curr1_crit_fault_log,
+			 ltc4283_show_curr1_crit_fault_log, NULL, "%llu\n");
+
+static int ltc4283_show_power1_failed_fault_log(void *arg, u64 *val)
+{
+	return ltc4283_show_fault_log(arg, val, LTC4283_PWR_FAIL_FAULT_MASK);
+}
+DEFINE_DEBUGFS_ATTRIBUTE(ltc4283_power1_failed_fault_log,
+			 ltc4283_show_power1_failed_fault_log, NULL, "%llu\n");
+
+static int ltc4283_show_power1_good_input_fault_log(void *arg, u64 *val)
+{
+	return ltc4283_show_fault_log(arg, val, LTC4283_PGI_FAULT_MASK);
+}
+DEFINE_DEBUGFS_ATTRIBUTE(ltc4283_power1_good_input_fault_log,
+			 ltc4283_show_power1_good_input_fault_log, NULL, "%llu\n");
+
+static void ltc4283_debugfs_init(struct ltc4283_hwmon *st, struct i2c_client *i2c)
+{
+	debugfs_create_file_unsafe("in0_crit_fault_log", 0400, i2c->debugfs, st,
+				   &ltc4283_in0_crit_fault_log);
+	debugfs_create_file_unsafe("in0_lcrit_fault_log", 0400, i2c->debugfs, st,
+				   &ltc4283_in0_lcrit_fault_log);
+	debugfs_create_file_unsafe("in11_fet_bad_fault_log", 0400, i2c->debugfs, st,
+				   &ltc4283_fet_bad_fault_log);
+	debugfs_create_file_unsafe("in11_fet_short_fault_log", 0400, i2c->debugfs, st,
+				   &ltc4283_fet_short_fault_log);
+	debugfs_create_file_unsafe("curr1_crit_fault_log", 0400, i2c->debugfs, st,
+				   &ltc4283_curr1_crit_fault_log);
+	debugfs_create_file_unsafe("power1_failed_fault_log", 0400, i2c->debugfs, st,
+				   &ltc4283_power1_failed_fault_log);
+	debugfs_create_file_unsafe("power1_good_input_fault_log", 0400, i2c->debugfs,
+				   st, &ltc4283_power1_good_input_fault_log);
+}
+
+static bool ltc4283_is_word_reg(unsigned int reg)
+{
+	return reg >= LTC4283_SENSE && reg <= LTC4283_ADIO34_MAX;
+}
+
+static int ltc4283_reg_read(void *context, unsigned int reg, unsigned int *val)
+{
+	struct i2c_client *client = context;
+	int ret;
+
+	if (ltc4283_is_word_reg(reg))
+		ret = i2c_smbus_read_word_swapped(client, reg);
+	else
+		ret = i2c_smbus_read_byte_data(client, reg);
+
+	if (ret < 0)
+		return ret;
+
+	*val = ret;
+	return 0;
+}
+
+static int ltc4283_reg_write(void *context, unsigned int reg, unsigned int val)
+{
+	struct i2c_client *client = context;
+
+	if (ltc4283_is_word_reg(reg))
+		return i2c_smbus_write_word_swapped(client, reg, val);
+
+	return i2c_smbus_write_byte_data(client, reg, val);
+}
+
+static const struct regmap_bus ltc4283_regmap_bus = {
+	.reg_read = ltc4283_reg_read,
+	.reg_write = ltc4283_reg_write,
+};
+
+static bool ltc4283_writable_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case LTC4283_SYSTEM_STATUS ... LTC4283_FAULT_STATUS:
+		return false;
+	case LTC4283_RESERVED_OC:
+		return false;
+	case LTC4283_RESERVED_86 ... LTC4283_RESERVED_8F:
+		return false;
+	case LTC4283_RESERVED_91 ... LTC4283_RESERVED_A1:
+		return false;
+	case LTC4283_RESERVED_A3:
+		return false;
+	case LTC4283_RESERVED_AC:
+		return false;
+	case LTC4283_POWER_PLAY_MSB ... LTC4283_POWER_PLAY_LSB:
+		return false;
+	case LTC4283_RESERVED_F1 ... LTC4283_RESERVED_FF:
+		return false;
+	default:
+		return true;
+	}
+}
+
+static const struct regmap_config ltc4283_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 16,
+	.max_register = 0xFF,
+	.writeable_reg = ltc4283_writable_reg,
+};
+
+static int ltc4283_probe(struct i2c_client *client)
+{
+	struct device *dev = &client->dev, *hwmon;
+	struct auxiliary_device *adev;
+	struct ltc4283_hwmon *st;
+	int ret, id;
+
+	st = devm_kzalloc(dev, sizeof(*st), GFP_KERNEL);
+	if (!st)
+		return -ENOMEM;
+
+	if (!i2c_check_functionality(client->adapter,
+				     I2C_FUNC_SMBUS_BYTE_DATA |
+				     I2C_FUNC_SMBUS_WORD_DATA |
+				     I2C_FUNC_SMBUS_READ_I2C_BLOCK))
+		return -EOPNOTSUPP;
+
+	st->client = client;
+	st->map = devm_regmap_init(dev, &ltc4283_regmap_bus, client,
+				   &ltc4283_regmap_config);
+	if (IS_ERR(st->map))
+		return dev_err_probe(dev, PTR_ERR(st->map),
+				     "Failed to create regmap\n");
+
+	ret = ltc4283_setup(st, dev);
+	if (ret)
+		return ret;
+
+	hwmon = devm_hwmon_device_register_with_info(dev, "ltc4283", st,
+						     &ltc4283_chip_info, NULL);
+
+	if (IS_ERR(hwmon))
+		return PTR_ERR(hwmon);
+
+	ltc4283_debugfs_init(st, client);
+
+	if (!st->gpio_mask)
+		return 0;
+
+	id = (client->adapter->nr << 10) | client->addr;
+	adev = __devm_auxiliary_device_create(dev, KBUILD_MODNAME, "gpio",
+					      &st->gpio_mask, id);
+	if (!adev)
+		return dev_err_probe(dev, -ENODEV, "Failed to add GPIO device\n");
+
+	return 0;
+}
+
+static const struct of_device_id ltc4283_of_match[] = {
+	{ .compatible = "adi,ltc4283" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, ltc4283_of_match);
+
+static const struct i2c_device_id ltc4283_i2c_id[] = {
+	{ "ltc4283" },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, ltc4283_i2c_id);
+
+static struct i2c_driver ltc4283_driver = {
+	.driver	= {
+		.name = "ltc4283",
+		.of_match_table = ltc4283_of_match,
+	},
+	.probe = ltc4283_probe,
+	.id_table = ltc4283_i2c_id,
+};
+module_i2c_driver(ltc4283_driver);
+
+MODULE_AUTHOR("Nuno Sá <nuno.sa@analog.com>");
+MODULE_DESCRIPTION("LTC4283 Hot Swap Controller driver");
+MODULE_LICENSE("GPL");