@@ -128,6 +128,7 @@ Hardware Monitoring Kernel Drivers
ltc4245
ltc4260
ltc4261
+ ltc4282
max127
max15301
max16064
new file mode 100644
@@ -0,0 +1,108 @@
+.. SPDX-License-Identifier: GPL-2.0-only
+
+Kernel drivers ltc4282
+==========================================
+
+Supported chips:
+
+ * Analog Devices LTC4282
+
+ Prefix: 'ltc4282'
+
+ Addresses scanned: - I2C 0x40 - 0x5A (7-bit)
+ Addresses scanned: - I2C 0x80 - 0xB4 with a step of 2 (8-bit)
+
+ Datasheet:
+
+ https://www.analog.com/media/en/technical-documentation/data-sheets/ltc4282.pdf
+
+Author: Nuno Sá <nuno.sa@analog.com>
+
+Description
+___________
+
+The LTC4282 hot swap controller allows a board to be safely inserted and removed
+from a live backplane. Using one or more external N-channel pass transistors,
+board supply voltage and inrush current are ramped up at an adjustable rate. An
+I2C interface and onboard ADC allows for monitoring of board current, voltage,
+power, energy and fault status. The device features analog foldback current
+limiting and supply monitoring for applications from 2.9V to 33V. Dual 12V gate
+drive allows high power applications to either share safe operating area across
+parallel MOSFETs or support a 2-stage start-up that first charges the load
+capacitance followed by enabling a low on-resistance path to the load. The
+LTC4282 is well suited to high power applications because the precise monitoring
+capability and accurate current limiting reduce the extremes in which both loads
+and power supplies must safely operate. Non-volatile configuration allows for
+flexibility in the autonomous generation of alerts and response to faults.
+
+Sysfs entries
+_____________
+
+The following attributes are supported. Limits are read-write and all the other
+attributes are read-only. Note that in0 and in1 are mutually exclusive. Enabling
+one disables the other and disabling one enables the other.
+
+======================= ==========================================
+in0_input Output voltage (mV).
+in0_min Undervoltage threshold
+in0_max Overvoltage threshold
+in0_lowest Lowest measured voltage
+in0_highest Highest measured voltage
+in0_reset_history Write 1 to reset in0 history
+in0_min_alarm Undervoltage alarm
+in0_max_alarm Overvoltage alarm
+in0_enable Enable/Disable VSOURCE monitoring
+in0_label Channel label (VSOURCE)
+
+in1_input Input voltage (mV).
+in1_min Undervoltage threshold
+in1_max Overvoltage threshold
+in1_lowest Lowest measured voltage
+in1_highest Highest measured voltage
+in1_reset_history Write 1 to reset in1 history
+in1_min_alarm Undervoltage alarm
+in1_max_alarm Overvoltage alarm
+in1_lcrit_alarm Critical Undervoltage alarm
+in1_crit_alarm Critical Overvoltage alarm
+in1_enable Enable/Disable VDD monitoring
+in1_label Channel label (VDD)
+
+in2_input GPIO voltage (mV)
+in2_min Undervoltage threshold
+in2_max Overvoltage threshold
+in2_lowest Lowest measured voltage
+in2_highest Highest measured voltage
+in2_reset_history Write 1 to reset in2 history
+in2_min_alarm Undervoltage alarm
+in2_max_alarm Overvoltage alarm
+in2_label Channel label (VGPIO)
+
+curr1_input Sense current (mA)
+curr1_min Undercurrent threshold
+curr1_max Overcurrent threshold
+curr1_lowest Lowest measured current
+curr1_highest Highest measured current
+curr1_reset_history Write 1 to reset curr1 history
+curr1_min_alarm Undercurrent alarm
+curr1_max_alarm Overcurrent alarm
+curr1_crit_alarm Critical Overcurrent alarm
+curr1_label Channel label (ISENSE)
+
+power1_input Power (in uW)
+power1_min Low power threshold
+power1_max High power threshold
+power1_input_lowest Historical minimum power use
+power1_input_highest Historical maximum power use
+power1_reset_history Write 1 to reset power1 history
+power1_min_alarm Low power alarm
+power1_max_alarm High power alarm
+power1_good Power considered good
+power1_label Channel label (Power)
+
+energy1_input Measured energy over time (in microJoule)
+energy1_enable Enable/Disable Energy accumulation
+
+fet_short_fault FET short alarm
+fet_bad_fault FET bad alarm
+fault_logs_reset Clears all the Logged Faults
+======================= ==========================================
@@ -12641,6 +12641,8 @@ M: Nuno Sa <nuno.sa@analog.com>
L: linux-hwmon@vger.kernel.org
S: Supported
F: Documentation/devicetree/bindings/hwmon/adi,ltc4282.yaml
+F: Documentation/hwmon/ltc4282.rst
+F: drivers/hwmon/ltc4282.c
LTC4306 I2C MULTIPLEXER DRIVER
M: Michael Hennerich <michael.hennerich@analog.com>
@@ -1027,6 +1027,17 @@ config SENSORS_LTC4261
This driver can also be built as a module. If so, the module will
be called ltc4261.
+config SENSORS_LTC4282
+ tristate "Analog Devices LTC4282"
+ depends on I2C
+ select REGMAP_I2C
+ help
+ If you say yes here you get support for Analog Devices LTC4282
+ High Current Hot Swap Controller I2C interface.
+
+ This driver can also be built as a module. If so, the module will
+ be called ltc4282.
+
config SENSORS_LTQ_CPUTEMP
bool "Lantiq cpu temperature sensor driver"
depends on SOC_XWAY
@@ -135,6 +135,7 @@ obj-$(CONFIG_SENSORS_LTC4222) += ltc4222.o
obj-$(CONFIG_SENSORS_LTC4245) += ltc4245.o
obj-$(CONFIG_SENSORS_LTC4260) += ltc4260.o
obj-$(CONFIG_SENSORS_LTC4261) += ltc4261.o
+obj-$(CONFIG_SENSORS_LTC4282) += ltc4282.o
obj-$(CONFIG_SENSORS_LTQ_CPUTEMP) += ltq-cputemp.o
obj-$(CONFIG_SENSORS_MAX1111) += max1111.o
obj-$(CONFIG_SENSORS_MAX127) += max127.o
new file mode 100644
@@ -0,0 +1,1705 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Analog Devices LTC4282 I2C High Current Hot Swap Controller over I2C
+ *
+ * Copyright 2023 Analog Devices Inc.
+ */
+#include <linux/bitfield.h>
+#include <linux/cleanup.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/debugfs.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/i2c.h>
+#include <linux/math.h>
+#include <linux/minmax.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/mutex.h>
+#include <linux/regmap.h>
+#include <linux/property.h>
+#include <linux/string.h>
+#include <linux/units.h>
+#include <linux/util_macros.h>
+
+#define LTC4282_CTRL_LSB 0x00
+ #define LTC4282_CTRL_OV_RETRY_MASK BIT(0)
+ #define LTC4282_CTRL_UV_RETRY_MASK BIT(1)
+ #define LTC4282_CTRL_OC_RETRY_MASK BIT(2)
+ #define LTC4282_CTRL_ON_ACTIVE_LOW_MASK BIT(5)
+ #define LTC4282_CTRL_ON_DELAY_MASK BIT(6)
+#define LTC4282_CTRL_MSB 0x01
+ #define LTC4282_CTRL_VIN_MODE_MASK GENMASK(1, 0)
+ #define LTC4282_CTRL_OV_MODE_MASK GENMASK(3, 2)
+ #define LTC4282_CTRL_UV_MODE_MASK GENMASK(5, 4)
+#define LTC4282_FAULT_LOG 0x04
+ #define LTC4282_OV_FAULT_MASK BIT(0)
+ #define LTC4282_UV_FAULT_MASK BIT(1)
+ #define LTC4282_OC_FAULT_MASK BIT(2)
+ #define LTC4282_POWER_BAD_FAULT_MASK BIT(3)
+ #define LTC4282_FET_SHORT_FAULT_MASK BIT(5)
+ #define LTC4282_FET_BAD_FAULT_MASK BIT(6)
+#define LTC4282_ADC_ALERT_LOG 0x05
+ #define LTC4282_GPIO_ALARM_L_MASK BIT(0)
+ #define LTC4282_GPIO_ALARM_H_MASK BIT(1)
+ #define LTC4282_VSOURCE_ALARM_L_MASK BIT(2)
+ #define LTC4282_VSOURCE_ALARM_H_MASK BIT(3)
+ #define LTC4282_VSENSE_ALARM_L_MASK BIT(4)
+ #define LTC4282_VSENSE_ALARM_H_MASK BIT(5)
+ #define LTC4282_POWER_ALARM_L_MASK BIT(6)
+ #define LTC4282_POWER_ALARM_H_MASK BIT(7)
+#define LTC4282_FET_BAD_FAULT_TIMEOUT 0x06
+ #define LTC4282_FET_BAD_MAX_TIMEOUT 255
+#define LTC4282_GPIO_CONFIG 0x07
+ #define LTC4282_GPIO_2_FET_STRESS_MASK BIT(1)
+ #define LTC4282_GPIO_1_CONFIG_MASK GENMASK(5, 4)
+#define LTC4282_VGPIO_MIN 0x08
+#define LTC4282_VGPIO_MAX 0x09
+#define LTC4282_VSOURCE_MIN 0x0a
+#define LTC4282_VSOURCE_MAX 0x0b
+#define LTC4282_VSENSE_MIN 0x0c
+#define LTC4282_VSENSE_MAX 0x0d
+#define LTC4282_POWER_MIN 0x0e
+#define LTC4282_POWER_MAX 0x0f
+#define LTC4282_CLK_DIV 0x10
+ #define LTC4282_CLK_DIV_MASK GENMASK(4, 0)
+ #define LTC4282_CLKOUT_MASK GENMASK(6, 5)
+#define LTC4282_ILIM_ADJUST 0x11
+ #define LTC4282_GPIO_MODE_MASK BIT(1)
+ #define LTC4282_VDD_MONITOR_MASK BIT(2)
+ #define LTC4282_FOLDBACK_MODE_MASK GENMASK(4, 3)
+ #define LTC4282_ILIM_ADJUST_MASK GENMASK(7, 5)
+#define LTC4282_ENERGY 0x12
+#define LTC4282_TIME_COUNTER 0x18
+#define LTC4282_ALERT_CTRL 0x1c
+ #define LTC4282_ALERT_OUT_MASK BIT(6)
+#define LTC4282_ADC_CTRL 0x1d
+ #define LTC4282_FAULT_LOG_EN_MASK BIT(2)
+ #define LTC4282_METER_HALT_MASK BIT(5)
+ #define LTC4282_METER_RESET_MASK BIT(6)
+ #define LTC4282_RESET_MASK BIT(7)
+#define LTC4282_STATUS_LSB 0x1e
+ #define LTC4282_OV_STATUS_MASK BIT(0)
+ #define LTC4282_UV_STATUS_MASK BIT(1)
+ #define LTC4282_VDD_STATUS_MASK \
+ (LTC4282_OV_STATUS_MASK | LTC4282_UV_STATUS_MASK)
+ #define LTC4282_OC_STATUS_MASK BIT(2)
+ #define LTC4282_POWER_GOOD_MASK BIT(3)
+ #define LTC4282_FET_SHORT_MASK BIT(5)
+ #define LTC4282_FET_BAD_STATUS_MASK BIT(6)
+#define LTC4282_STATUS_MSB 0x1f
+#define LTC4282_RESERVED_1 0x32
+#define LTC4282_RESERVED_2 0x33
+#define LTC4282_VGPIO 0x34
+#define LTC4282_VGPIO_LOWEST 0x36
+#define LTC4282_VGPIO_HIGHEST 0x38
+#define LTC4282_VSOURCE 0x3a
+#define LTC4282_VSOURCE_LOWEST 0x3c
+#define LTC4282_VSOURCE_HIGHEST 0x3e
+#define LTC4282_VSENSE 0x40
+#define LTC4282_VSENSE_LOWEST 0x42
+#define LTC4282_VSENSE_HIGHEST 0x44
+#define LTC4282_POWER 0x46
+#define LTC4282_POWER_LOWEST 0x48
+#define LTC4282_POWER_HIGHEST 0x4a
+#define LTC4282_RESERVED_3 0x50
+
+#define LTC4282_CLKIN_MIN (250 * KILO)
+#define LTC4282_CLKIN_MAX (15500 * KILO)
+#define LTC4282_CLKIN_RANGE (LTC4282_CLKIN_MAX - LTC4282_CLKIN_MIN + 1)
+#define LTC4282_CLKOUT_SYSTEM (250 * KILO)
+#define LTC4282_CLKOUT_CNV 15
+
+enum {
+ LTC4282_CHAN_VSOURCE,
+ LTC4282_CHAN_VDD,
+ LTC4282_CHAN_VGPIO,
+};
+
+struct ltc4282_cache {
+ u32 in_max_raw;
+ u32 in_min_raw;
+ long in_highest;
+ long in_lowest;
+ bool en;
+};
+
+struct ltc4282_state {
+ struct regmap *map;
+ /* Protect against multiple accesses to the device registers */
+ struct mutex lock;
+ struct clk_hw clk_hw;
+ /*
+ * Used to cache values for VDD/VSOURCE depending which will be used
+ * when hwmon is not enabled for that channel. Needed because they share
+ * the same registers.
+ */
+ struct ltc4282_cache in0_1_cache[LTC4282_CHAN_VGPIO];
+ long power_max;
+ u32 rsense;
+ u32 vin_mode;
+ u16 vfs_out;
+ bool energy_en;
+};
+
+enum {
+ LTC4282_VIN_3_3V,
+ LTC4282_VIN_5V,
+ LTC4282_VIN_12V,
+ LTC4282_VIN_24V,
+};
+
+enum {
+ LTC4282_CLKOUT_NONE,
+ LTC4282_CLKOUT_INT,
+ LTC4282_CLKOUT_TICK,
+};
+
+static int ltc4282_set_rate(struct clk_hw *hw,
+ unsigned long rate, unsigned long parent_rate)
+{
+ struct ltc4282_state *st = container_of(hw, struct ltc4282_state,
+ clk_hw);
+ u32 val = LTC4282_CLKOUT_INT;
+
+ if (rate == LTC4282_CLKOUT_CNV)
+ val = LTC4282_CLKOUT_TICK;
+
+ return regmap_update_bits(st->map, LTC4282_CLK_DIV, LTC4282_CLKOUT_MASK,
+ FIELD_PREP(LTC4282_CLKOUT_MASK, val));
+}
+
+/*
+ * Note the 15HZ conversion rate assumes 12bit ADC which is what we are
+ * supporting for now.
+ */
+static unsigned int ltc4282_out_rates[] = {
+ LTC4282_CLKOUT_CNV, LTC4282_CLKOUT_SYSTEM
+};
+
+static long ltc4282_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *parent_rate)
+{
+ int idx = find_closest(rate, ltc4282_out_rates,
+ ARRAY_SIZE(ltc4282_out_rates));
+
+ return ltc4282_out_rates[idx];
+}
+
+static unsigned long ltc4282_recalc_rate(struct clk_hw *hw,
+ unsigned long parent)
+{
+ struct ltc4282_state *st = container_of(hw, struct ltc4282_state,
+ clk_hw);
+ u32 clkdiv;
+ int ret;
+
+ ret = regmap_read(st->map, LTC4282_CLK_DIV, &clkdiv);
+ if (ret)
+ return 0;
+
+ clkdiv = FIELD_GET(LTC4282_CLKOUT_MASK, clkdiv);
+ if (!clkdiv)
+ return 0;
+ if (clkdiv == LTC4282_CLKOUT_INT)
+ return LTC4282_CLKOUT_SYSTEM;
+
+ return LTC4282_CLKOUT_CNV;
+}
+
+static void ltc4282_disable(struct clk_hw *clk_hw)
+{
+ struct ltc4282_state *st = container_of(clk_hw, struct ltc4282_state,
+ clk_hw);
+
+ regmap_clear_bits(st->map, LTC4282_CLK_DIV, LTC4282_CLKOUT_MASK);
+}
+
+static int ltc4282_read_voltage_word(const struct ltc4282_state *st, u32 reg,
+ u32 fs, long *val)
+{
+ __be16 in;
+ int ret;
+
+ ret = regmap_bulk_read(st->map, reg, &in, sizeof(in));
+ if (ret)
+ return ret;
+
+ /*
+ * This is also used to calculate current in which case fs comes in
+ * 10 * uV. Hence the ULL usage.
+ */
+ *val = DIV_ROUND_CLOSEST_ULL(be16_to_cpu(in) * (u64)fs, U16_MAX);
+ return 0;
+}
+
+static int ltc4282_read_voltage_byte_cached(const struct ltc4282_state *st,
+ u32 reg, u32 fs, long *val,
+ u32 *cached_raw)
+{
+ int ret;
+ u32 in;
+
+ if (cached_raw) {
+ in = *cached_raw;
+ } else {
+ ret = regmap_read(st->map, reg, &in);
+ if (ret)
+ return ret;
+ }
+
+ *val = DIV_ROUND_CLOSEST(in * fs, U8_MAX);
+ return 0;
+}
+
+static int ltc4282_read_voltage_byte(const struct ltc4282_state *st, u32 reg,
+ u32 fs, long *val)
+{
+ return ltc4282_read_voltage_byte_cached(st, reg, fs, val, NULL);
+}
+
+static int __ltc4282_read_alarm(struct ltc4282_state *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 != LTC4282_STATUS_LSB && reg != LTC4282_FAULT_LOG)
+ return regmap_clear_bits(st->map, reg, mask);
+
+ return 0;
+}
+
+static int ltc4282_read_alarm(struct ltc4282_state *st, u32 reg, u32 mask,
+ long *val)
+{
+ guard(mutex)(&st->lock);
+ return __ltc4282_read_alarm(st, reg, mask, val);
+}
+
+static int ltc4282_vdd_source_read_in(struct ltc4282_state *st, u32 channel,
+ long *val)
+{
+ guard(mutex)(&st->lock);
+ if (!st->in0_1_cache[channel].en)
+ return -ENODATA;
+
+ return ltc4282_read_voltage_word(st, LTC4282_VSOURCE, st->vfs_out, val);
+}
+
+static int ltc4282_vdd_source_read_hist(struct ltc4282_state *st, u32 reg,
+ u32 channel, long *cached, long *val)
+{
+ int ret;
+
+ guard(mutex)(&st->lock);
+ if (!st->in0_1_cache[channel].en) {
+ *val = *cached;
+ return 0;
+ }
+
+ ret = ltc4282_read_voltage_word(st, reg, st->vfs_out, val);
+ if (ret)
+ return ret;
+
+ *cached = *val;
+ return 0;
+}
+
+static int ltc4282_vdd_source_read_lim(struct ltc4282_state *st, u32 reg,
+ u32 channel, u32 *cached, long *val)
+{
+ guard(mutex)(&st->lock);
+ if (!st->in0_1_cache[channel].en)
+ return ltc4282_read_voltage_byte_cached(st, reg, st->vfs_out,
+ val, cached);
+
+ return ltc4282_read_voltage_byte(st, reg, st->vfs_out, val);
+}
+
+static int ltc4282_vdd_source_read_alm(struct ltc4282_state *st, u32 mask,
+ u32 channel, long *val)
+{
+ guard(mutex)(&st->lock);
+ if (!st->in0_1_cache[channel].en) {
+ /*
+ * Do this otherwise alarms can get confused because we clear
+ * them after reading them. So, if someone mistakenly reads
+ * VSOURCE right before VDD (or the other way around), we might
+ * get no alarm just because it was cleared when reading VSOURCE
+ * and had no time for a new conversion and thus having the
+ * alarm again.
+ */
+ *val = 0;
+ return 0;
+ }
+
+ return __ltc4282_read_alarm(st, LTC4282_ADC_ALERT_LOG, mask, val);
+}
+
+static int ltc4282_read_in(struct ltc4282_state *st, u32 attr, long *val,
+ u32 channel)
+{
+ switch (attr) {
+ case hwmon_in_input:
+ if (channel == LTC4282_CHAN_VGPIO)
+ return ltc4282_read_voltage_word(st, LTC4282_VGPIO,
+ 1280, val);
+
+ return ltc4282_vdd_source_read_in(st, channel, val);
+ case hwmon_in_highest:
+ if (channel == LTC4282_CHAN_VGPIO)
+ return ltc4282_read_voltage_word(st,
+ LTC4282_VGPIO_HIGHEST,
+ 1280, val);
+
+ return ltc4282_vdd_source_read_hist(st, LTC4282_VSOURCE_HIGHEST,
+ channel,
+ &st->in0_1_cache[channel].in_highest, val);
+ case hwmon_in_lowest:
+ if (channel == LTC4282_CHAN_VGPIO)
+ ltc4282_read_voltage_word(st, LTC4282_VGPIO_LOWEST,
+ 1280, val);
+
+ return ltc4282_vdd_source_read_hist(st, LTC4282_VSOURCE_LOWEST,
+ channel,
+ &st->in0_1_cache[channel].in_lowest, val);
+ case hwmon_in_max_alarm:
+ if (channel == LTC4282_CHAN_VGPIO)
+ return ltc4282_read_alarm(st, LTC4282_ADC_ALERT_LOG,
+ LTC4282_GPIO_ALARM_H_MASK,
+ val);
+
+ return ltc4282_vdd_source_read_alm(st,
+ LTC4282_VSOURCE_ALARM_H_MASK,
+ channel, val);
+ case hwmon_in_min_alarm:
+ if (channel == LTC4282_CHAN_VGPIO)
+ ltc4282_read_alarm(st, LTC4282_ADC_ALERT_LOG,
+ LTC4282_GPIO_ALARM_L_MASK, val);
+
+ return ltc4282_vdd_source_read_alm(st,
+ LTC4282_VSOURCE_ALARM_L_MASK,
+ channel, val);
+ case hwmon_in_crit_alarm:
+ return ltc4282_read_alarm(st, LTC4282_STATUS_LSB,
+ LTC4282_OV_STATUS_MASK, val);
+ case hwmon_in_lcrit_alarm:
+ return ltc4282_read_alarm(st, LTC4282_STATUS_LSB,
+ LTC4282_UV_STATUS_MASK, val);
+ case hwmon_in_max:
+ if (channel == LTC4282_CHAN_VGPIO)
+ return ltc4282_read_voltage_byte(st, LTC4282_VGPIO_MAX,
+ 1280, val);
+
+ return ltc4282_vdd_source_read_lim(st, LTC4282_VSOURCE_MAX,
+ channel,
+ &st->in0_1_cache[channel].in_max_raw, val);
+ case hwmon_in_min:
+ if (channel == LTC4282_CHAN_VGPIO)
+ return ltc4282_read_voltage_byte(st, LTC4282_VGPIO_MIN,
+ 1280, val);
+
+ return ltc4282_vdd_source_read_lim(st, LTC4282_VSOURCE_MIN,
+ channel,
+ &st->in0_1_cache[channel].in_min_raw, val);
+ case hwmon_in_enable:
+ scoped_guard(mutex, &st->lock) {
+ *val = st->in0_1_cache[channel].en;
+ }
+ return 0;
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
+static int ltc4282_read_current_word(const struct ltc4282_state *st, u32 reg,
+ long *val)
+{
+ long in;
+ int ret;
+
+ /*
+ * We pass in full scale in 10 * micro (note that 40 is already
+ * millivolt) so we have better approximations to calculate current.
+ */
+ ret = ltc4282_read_voltage_word(st, reg, DECA * 40 * MILLI, &in);
+ if (ret)
+ return ret;
+
+ *val = DIV_ROUND_CLOSEST(in * MILLI, st->rsense);
+
+ return 0;
+}
+
+static int ltc4282_read_current_byte(const struct ltc4282_state *st, u32 reg,
+ long *val)
+{
+ long in;
+ int ret;
+
+ ret = ltc4282_read_voltage_byte(st, reg, DECA * 40 * MILLI, &in);
+ if (ret)
+ return ret;
+
+ *val = DIV_ROUND_CLOSEST(in * MILLI, st->rsense);
+
+ return 0;
+}
+
+static int ltc4282_read_curr(struct ltc4282_state *st, const u32 attr,
+ long *val)
+{
+ switch (attr) {
+ case hwmon_curr_input:
+ return ltc4282_read_current_word(st, LTC4282_VSENSE, val);
+ case hwmon_curr_highest:
+ return ltc4282_read_current_word(st, LTC4282_VSENSE_HIGHEST,
+ val);
+ case hwmon_curr_lowest:
+ return ltc4282_read_current_word(st, LTC4282_VSENSE_LOWEST,
+ val);
+ case hwmon_curr_max:
+ return ltc4282_read_current_byte(st, LTC4282_VSENSE_MAX, val);
+ case hwmon_curr_min:
+ return ltc4282_read_current_byte(st, LTC4282_VSENSE_MIN, val);
+ case hwmon_curr_max_alarm:
+ return ltc4282_read_alarm(st, LTC4282_ADC_ALERT_LOG,
+ LTC4282_VSENSE_ALARM_H_MASK, val);
+ case hwmon_curr_min_alarm:
+ return ltc4282_read_alarm(st, LTC4282_ADC_ALERT_LOG,
+ LTC4282_VSENSE_ALARM_L_MASK, val);
+ case hwmon_curr_crit_alarm:
+ return ltc4282_read_alarm(st, LTC4282_STATUS_LSB,
+ LTC4282_OC_STATUS_MASK, val);
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
+static int ltc4282_read_power_word(const struct ltc4282_state *st, u32 reg,
+ long *val)
+{
+ u64 temp = DECA * 40ULL * st->vfs_out * BIT(16), temp_2;
+ __be16 raw;
+ u16 power;
+ int ret;
+
+ ret = regmap_bulk_read(st->map, reg, &raw, sizeof(raw));
+ if (ret)
+ return ret;
+
+ power = be16_to_cpu(raw);
+ /*
+ * Power is given by:
+ * P = CODE(16b) * 0.040 * Vfs(out) * 2^16 / ((2^16 - 1)^2 * Rsense)
+ */
+ if (check_mul_overflow(power * temp, MICRO, &temp_2)) {
+ temp = DIV_ROUND_CLOSEST_ULL(power * temp, U16_MAX);
+ *val = DIV64_U64_ROUND_CLOSEST(temp * MICRO,
+ U16_MAX * (u64)st->rsense);
+ return 0;
+ }
+
+ *val = DIV64_U64_ROUND_CLOSEST(temp_2,
+ st->rsense * int_pow(U16_MAX, 2));
+
+ return 0;
+}
+
+static int ltc4282_read_power_byte(const struct ltc4282_state *st, u32 reg,
+ long *val)
+{
+ u32 power;
+ u64 temp;
+ int ret;
+
+ ret = regmap_read(st->map, reg, &power);
+ if (ret)
+ return ret;
+
+ temp = power * 40 * DECA * st->vfs_out * BIT_ULL(8);
+ *val = DIV64_U64_ROUND_CLOSEST(temp * MICRO,
+ int_pow(U8_MAX, 2) * st->rsense);
+
+ return 0;
+}
+
+static int ltc4282_read_energy(const struct ltc4282_state *st, u64 *val)
+{
+ u64 temp, energy;
+ __be64 raw;
+ int ret;
+
+ ret = regmap_bulk_read(st->map, LTC4282_ENERGY, &raw, 6);
+ if (ret)
+ return ret;
+
+ energy = be64_to_cpu(raw) >> 16;
+ /*
+ * The formula for energy is given by:
+ * E = CODE(48b) * 0.040 * Vfs(out) * Tconv * 256 /
+ * ((2^16 - 1)^2 * Rsense)
+ *
+ * Since we only support 12bit ADC, Tconv = 0.065535s. Passing Vfs(out)
+ * and 0.040 to mV and Tconv to us, we can simplify the formula to:
+ * E = CODE(48b) * 40 * Vfs(out) * 256 / (U16_MAX * Rsense)
+ *
+ * As Rsense can have tenths of micro-ohm resolution, we need to
+ * multiply by DECA to get microujoule.
+ */
+ if (check_mul_overflow(DECA * st->vfs_out * 40 * BIT(8), energy, &temp)) {
+ temp = DIV_ROUND_CLOSEST(DECA * st->vfs_out * 40 * BIT(8), U16_MAX);
+ *val = DIV_ROUND_CLOSEST_ULL(temp * energy, st->rsense);
+ return 0;
+ }
+
+ *val = DIV64_U64_ROUND_CLOSEST(temp, U16_MAX * (u64)st->rsense);
+
+ return 0;
+}
+
+static int ltc4282_read_power(struct ltc4282_state *st, const u32 attr,
+ long *val)
+{
+ switch (attr) {
+ case hwmon_power_input:
+ return ltc4282_read_power_word(st, LTC4282_POWER, val);
+ case hwmon_power_input_highest:
+ return ltc4282_read_power_word(st, LTC4282_POWER_HIGHEST, val);
+ case hwmon_power_input_lowest:
+ return ltc4282_read_power_word(st, LTC4282_POWER_LOWEST, val);
+ case hwmon_power_max_alarm:
+ return ltc4282_read_alarm(st, LTC4282_ADC_ALERT_LOG,
+ LTC4282_POWER_ALARM_H_MASK, val);
+ case hwmon_power_min_alarm:
+ return ltc4282_read_alarm(st, LTC4282_ADC_ALERT_LOG,
+ LTC4282_POWER_ALARM_L_MASK, val);
+ case hwmon_power_max:
+ return ltc4282_read_power_byte(st, LTC4282_POWER_MAX, val);
+ case hwmon_power_min:
+ return ltc4282_read_power_byte(st, LTC4282_POWER_MIN, val);
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
+static int ltc4282_read(struct device *dev, enum hwmon_sensor_types type,
+ u32 attr, int channel, long *val)
+{
+ struct ltc4282_state *st = dev_get_drvdata(dev);
+
+ switch (type) {
+ case hwmon_in:
+ return ltc4282_read_in(st, attr, val, channel);
+ case hwmon_curr:
+ return ltc4282_read_curr(st, attr, val);
+ case hwmon_power:
+ return ltc4282_read_power(st, attr, val);
+ case hwmon_energy:
+ scoped_guard(mutex, &st->lock) {
+ *val = st->energy_en;
+ }
+ return 0;
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
+static int ltc4282_write_power_byte(const struct ltc4282_state *st, u32 reg,
+ long val)
+{
+ u32 power;
+ u64 temp;
+
+ if (val > st->power_max)
+ val = st->power_max;
+
+ temp = val * int_pow(U8_MAX, 2) * st->rsense;
+ power = DIV64_U64_ROUND_CLOSEST(temp,
+ MICRO * DECA * 256ULL * st->vfs_out * 40);
+
+ return regmap_write(st->map, reg, power);
+}
+
+static int __ltc4282_write_history(const struct ltc4282_state *st, u32 reg,
+ long lowest, long highest)
+{
+ __be16 __raw;
+ u16 tmp;
+ int ret;
+
+ tmp = DIV_ROUND_CLOSEST(U16_MAX * lowest, st->vfs_out);
+
+ __raw = cpu_to_be16(tmp);
+
+ ret = regmap_bulk_write(st->map, reg, &__raw, 2);
+ if (ret)
+ return ret;
+
+ tmp = DIV_ROUND_CLOSEST(U16_MAX * highest, st->vfs_out);
+
+ __raw = cpu_to_be16(tmp);
+
+ return regmap_bulk_write(st->map, reg + 2, &__raw, 2);
+}
+
+static int ltc4282_write_history(struct ltc4282_state *st, u32 reg, long lowest,
+ long highest)
+{
+ guard(mutex)(&st->lock);
+ return __ltc4282_write_history(st, reg, lowest, highest);
+}
+
+static int ltc4282_write_power(struct ltc4282_state *st, u32 attr,
+ long val)
+{
+ switch (attr) {
+ case hwmon_power_max:
+ return ltc4282_write_power_byte(st, LTC4282_POWER_MAX, val);
+ case hwmon_power_min:
+ return ltc4282_write_power_byte(st, LTC4282_POWER_MIN, val);
+ case hwmon_power_reset_history:
+ return ltc4282_write_history(st, LTC4282_POWER_LOWEST, 0, 0);
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
+static int ltc4282_write_voltage_byte_cached(const struct ltc4282_state *st,
+ u32 reg, u32 fs, long val,
+ u32 *cache_raw)
+{
+ u32 in;
+
+ if (val >= fs)
+ in = U8_MAX;
+ else
+ in = DIV_ROUND_CLOSEST(val * U8_MAX, fs);
+
+ if (cache_raw) {
+ *cache_raw = in;
+ return 0;
+ }
+
+ return regmap_write(st->map, reg, in);
+}
+
+static int ltc4282_write_voltage_byte(const struct ltc4282_state *st, u32 reg,
+ u32 fs, long val)
+{
+ return ltc4282_write_voltage_byte_cached(st, reg, fs, val, NULL);
+}
+
+static int ltc4282_cache_history(struct ltc4282_state *st, u32 channel)
+{
+ long val;
+ int ret;
+
+ ret = ltc4282_read_voltage_word(st, LTC4282_VSOURCE_LOWEST, st->vfs_out,
+ &val);
+ if (ret)
+ return ret;
+
+ st->in0_1_cache[channel].in_lowest = val;
+
+ ret = ltc4282_read_voltage_word(st, LTC4282_VSOURCE_HIGHEST,
+ st->vfs_out, &val);
+ if (ret)
+ return ret;
+
+ st->in0_1_cache[channel].in_highest = val;
+
+ ret = regmap_read(st->map, LTC4282_VSOURCE_MIN,
+ &st->in0_1_cache[channel].in_min_raw);
+ if (ret)
+ return ret;
+
+ return regmap_read(st->map, LTC4282_VSOURCE_MAX,
+ &st->in0_1_cache[channel].in_max_raw);
+}
+
+static int ltc4282_cache_sync(struct ltc4282_state *st, u32 channel)
+{
+ int ret;
+
+ ret = __ltc4282_write_history(st, LTC4282_VSOURCE_LOWEST,
+ st->in0_1_cache[channel].in_lowest,
+ st->in0_1_cache[channel].in_highest);
+ if (ret)
+ return ret;
+
+ ret = regmap_write(st->map, LTC4282_VSOURCE_MIN,
+ st->in0_1_cache[channel].in_min_raw);
+
+ return regmap_write(st->map, LTC4282_VSOURCE_MAX,
+ st->in0_1_cache[channel].in_max_raw);
+}
+
+static int ltc4282_vdd_source_write_lim(struct ltc4282_state *st, u32 reg,
+ int channel, u32 *cache, long val)
+{
+ int ret;
+
+ guard(mutex)(&st->lock);
+ if (st->in0_1_cache[channel].en)
+ ret = ltc4282_write_voltage_byte(st, reg, st->vfs_out, val);
+ else
+ ret = ltc4282_write_voltage_byte_cached(st, reg, st->vfs_out,
+ val, cache);
+
+ return ret;
+}
+
+static int ltc4282_vdd_source_write_hist(struct ltc4282_state *st, int channel)
+{
+ int ret;
+
+ guard(mutex)(&st->lock);
+ if (st->in0_1_cache[channel].en) {
+ ret = __ltc4282_write_history(st, LTC4282_VSOURCE_LOWEST, 0, 0);
+ if (ret)
+ return ret;
+ }
+
+ st->in0_1_cache[channel].in_lowest = 0;
+ st->in0_1_cache[channel].in_highest = 0;
+
+ return 0;
+}
+
+/*
+ * We need to mux between VSOURCE and VDD which means they are mutually
+ * exclusive. Moreover, we can't really disable both VDD and VSOURCE as the ADC
+ * is continuously running (we cannot independently halt it without also
+ * stopping VGPIO). Hence, the logic is that disabling or enabling VDD will
+ * automatically have the reverse effect on VSOURCE and vice-versa.
+ */
+static int ltc4282_vdd_source_enable(struct ltc4282_state *st, int channel,
+ long val)
+{
+ int ret, other_chan = ~channel & 0x1;
+ u8 __val = val;
+
+ guard(mutex)(&st->lock);
+ if (st->in0_1_cache[channel].en == !!val)
+ return 0;
+
+ /* clearing the bit makes the ADC to monitor VDD */
+ if (channel == LTC4282_CHAN_VDD)
+ __val = !__val;
+
+ ret = regmap_update_bits(st->map, LTC4282_ILIM_ADJUST,
+ LTC4282_VDD_MONITOR_MASK,
+ FIELD_PREP(LTC4282_VDD_MONITOR_MASK, !!__val));
+ if (ret)
+ return ret;
+
+ st->in0_1_cache[channel].en = !!val;
+ st->in0_1_cache[other_chan].en = !val;
+
+ if (st->in0_1_cache[channel].en) {
+ /*
+ * Then, we are disabling @other_chan. Let's save it's current
+ * history.
+ */
+ ret = ltc4282_cache_history(st, other_chan);
+ if (ret)
+ return ret;
+
+ return ltc4282_cache_sync(st, channel);
+ }
+ /*
+ * Then, we are enabling @other_chan. We need to do the opposite from
+ * above.
+ */
+ ret = ltc4282_cache_history(st, channel);
+ if (ret)
+ return ret;
+
+ return ltc4282_cache_sync(st, other_chan);
+}
+
+static int ltc4282_write_in(struct ltc4282_state *st, u32 attr, long val,
+ int channel)
+{
+ switch (attr) {
+ case hwmon_in_max:
+ if (channel == LTC4282_CHAN_VGPIO)
+ return ltc4282_write_voltage_byte(st, LTC4282_VGPIO_MAX,
+ 1280, val);
+
+ return ltc4282_vdd_source_write_lim(st, LTC4282_VSOURCE_MAX,
+ channel,
+ &st->in0_1_cache[channel].in_max_raw, val);
+ case hwmon_in_min:
+ if (channel == LTC4282_CHAN_VGPIO)
+ return ltc4282_write_voltage_byte(st, LTC4282_VGPIO_MIN,
+ 1280, val);
+
+ return ltc4282_vdd_source_write_lim(st, LTC4282_VSOURCE_MIN,
+ channel,
+ &st->in0_1_cache[channel].in_min_raw, val);
+ case hwmon_in_reset_history:
+ if (channel == LTC4282_CHAN_VGPIO)
+ return ltc4282_write_history(st, LTC4282_VGPIO_LOWEST,
+ 0, 0);
+
+ return ltc4282_vdd_source_write_hist(st, channel);
+ case hwmon_in_enable:
+ return ltc4282_vdd_source_enable(st, channel, val);
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
+static int ltc4282_write_curr(struct ltc4282_state *st, u32 attr,
+ long val)
+{
+ /* need to pass it in millivolt */
+ u32 in = DIV_ROUND_CLOSEST_ULL((u64)val * st->rsense, DECA * MICRO);
+
+ switch (attr) {
+ case hwmon_curr_max:
+ return ltc4282_write_voltage_byte(st, LTC4282_VSENSE_MAX, 40,
+ in);
+ case hwmon_curr_min:
+ return ltc4282_write_voltage_byte(st, LTC4282_VSENSE_MIN, 40,
+ in);
+ case hwmon_curr_reset_history:
+ return ltc4282_write_history(st, LTC4282_VSENSE_LOWEST, 0, 0);
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
+static int ltc4282_energy_enable_set(struct ltc4282_state *st, long val)
+{
+ int ret;
+
+ guard(mutex)(&st->lock);
+ /* setting the bit halts the meter */
+ ret = regmap_update_bits(st->map, LTC4282_ADC_CTRL,
+ LTC4282_METER_HALT_MASK,
+ FIELD_PREP(LTC4282_METER_HALT_MASK, !val));
+ if (ret)
+ return ret;
+
+ st->energy_en = !!val;
+
+ return 0;
+}
+
+static int ltc4282_write(struct device *dev,
+ enum hwmon_sensor_types type,
+ u32 attr, int channel, long val)
+{
+ struct ltc4282_state *st = dev_get_drvdata(dev);
+
+ switch (type) {
+ case hwmon_power:
+ return ltc4282_write_power(st, attr, val);
+ case hwmon_in:
+ return ltc4282_write_in(st, attr, val, channel);
+ case hwmon_curr:
+ return ltc4282_write_curr(st, attr, val);
+ case hwmon_energy:
+ return ltc4282_energy_enable_set(st, val);
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
+static umode_t ltc4282_in_is_visible(const struct ltc4282_state *st, u32 attr)
+{
+ 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:
+ return 0444;
+ case hwmon_in_max:
+ case hwmon_in_min:
+ case hwmon_in_enable:
+ case hwmon_in_reset_history:
+ return 0644;
+ default:
+ return 0;
+ }
+}
+
+static umode_t ltc4282_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:
+ case hwmon_curr_reset_history:
+ return 0644;
+ default:
+ return 0;
+ }
+}
+
+static umode_t ltc4282_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:
+ case hwmon_power_reset_history:
+ return 0644;
+ default:
+ return 0;
+ }
+}
+
+static umode_t ltc4282_is_visible(const void *data,
+ enum hwmon_sensor_types type,
+ u32 attr, int channel)
+{
+ switch (type) {
+ case hwmon_in:
+ return ltc4282_in_is_visible(data, attr);
+ case hwmon_curr:
+ return ltc4282_curr_is_visible(attr);
+ case hwmon_power:
+ return ltc4282_power_is_visible(attr);
+ case hwmon_energy:
+ /* hwmon_energy_enable */
+ return 0644;
+ default:
+ return 0;
+ }
+}
+
+static const char * const ltc4282_in_strs[] = {
+ "VSOURCE", "VDD", "VGPIO"
+};
+
+static int ltc4282_read_labels(struct device *dev,
+ enum hwmon_sensor_types type,
+ u32 attr, int channel, const char **str)
+{
+ switch (type) {
+ case hwmon_in:
+ *str = ltc4282_in_strs[channel];
+ return 0;
+ case hwmon_curr:
+ *str = "ISENSE";
+ return 0;
+ case hwmon_power:
+ *str = "Power";
+ return 0;
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
+static ssize_t ltc4282_energy_show(struct device *dev,
+ struct device_attribute *da, char *buf)
+{
+ struct ltc4282_state *st = dev_get_drvdata(dev);
+ u64 energy;
+ int ret;
+
+ guard(mutex)(&st->lock);
+ if (!st->energy_en)
+ return -ENODATA;
+
+ ret = ltc4282_read_energy(st, &energy);
+ if (ret < 0)
+ return ret;
+
+ return sysfs_emit(buf, "%llu\n", energy);
+}
+
+static ssize_t ltc4282_status_show(struct device *dev,
+ struct device_attribute *da, char *buf)
+{
+ struct ltc4282_state *st = dev_get_drvdata(dev);
+ struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
+ long alarm;
+ int ret;
+
+ ret = ltc4282_read_alarm(st, LTC4282_STATUS_LSB, attr->index, &alarm);
+ if (ret)
+ return ret;
+
+ return sysfs_emit(buf, "%lu\n", alarm);
+}
+
+static ssize_t ltc4282_clear_faults_store(struct device *dev,
+ struct device_attribute *da,
+ const char *buf, size_t len)
+{
+ struct ltc4282_state *st = dev_get_drvdata(dev);
+ int ret;
+
+ ret = regmap_write(st->map, LTC4282_FAULT_LOG, 0);
+ if (ret)
+ return ret;
+
+ return len;
+}
+
+static const struct clk_ops ltc4282_ops = {
+ .recalc_rate = ltc4282_recalc_rate,
+ .round_rate = ltc4282_round_rate,
+ .set_rate = ltc4282_set_rate,
+ .disable = ltc4282_disable,
+};
+
+static int ltc428_clk_provider_setup(struct ltc4282_state *st,
+ struct device *dev)
+{
+ struct clk_init_data init;
+ int ret;
+
+ if (!IS_ENABLED(CONFIG_COMMON_CLK))
+ return 0;
+
+ init.name = "ltc4282-clk";
+ init.ops = <c4282_ops;
+ init.flags = CLK_GET_RATE_NOCACHE;
+ st->clk_hw.init = &init;
+
+ ret = devm_clk_hw_register(dev, &st->clk_hw);
+ if (ret)
+ return ret;
+
+ return devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get,
+ &st->clk_hw);
+}
+
+static int ltc428_clks_setup(struct ltc4282_state *st, struct device *dev)
+{
+ unsigned long rate;
+ struct clk *clkin;
+ u32 val;
+ int ret;
+
+ ret = ltc428_clk_provider_setup(st, dev);
+ if (ret)
+ return ret;
+
+ clkin = devm_clk_get_optional_enabled(dev, NULL);
+ if (IS_ERR(clkin))
+ return dev_err_probe(dev, PTR_ERR(clkin),
+ "Failed to get clkin");
+ if (!clkin)
+ return 0;
+
+ rate = clk_get_rate(clkin);
+ if (in_range(rate, LTC4282_CLKIN_MIN, LTC4282_CLKIN_RANGE))
+ return dev_err_probe(dev, -EINVAL,
+ "Invalid clkin range(%lu) [%lu %lu]\n",
+ rate, LTC4282_CLKIN_MIN,
+ LTC4282_CLKIN_MAX);
+
+ /*
+ * Clocks faster than 250KHZ should be reduced to 250KHZ. The clock
+ * frequency is divided by twice the value in the register.
+ */
+ val = rate / (2 * LTC4282_CLKIN_MIN);
+
+ return regmap_update_bits(st->map, LTC4282_CLK_DIV,
+ LTC4282_CLK_DIV_MASK,
+ FIELD_PREP(LTC4282_CLK_DIV_MASK, val));
+}
+
+static const int ltc4282_curr_lim_uv[] = {
+ 12500, 15625, 18750, 21875, 25000, 28125, 31250, 34375
+};
+
+static int ltc4282_get_defaults(struct ltc4282_state *st, u32 *curr_lim_uv)
+{
+ u32 reg_val, ilm_adjust;
+ int ret;
+
+ ret = regmap_read(st->map, LTC4282_ADC_CTRL, ®_val);
+ if (ret)
+ return ret;
+
+ st->energy_en = !FIELD_GET(LTC4282_METER_HALT_MASK, reg_val);
+
+ ret = regmap_read(st->map, LTC4282_CTRL_MSB, ®_val);
+ if (ret)
+ return ret;
+
+ st->vin_mode = FIELD_GET(LTC4282_CTRL_VIN_MODE_MASK, reg_val);
+
+ ret = regmap_read(st->map, LTC4282_ILIM_ADJUST, ®_val);
+ if (ret)
+ return ret;
+
+ ilm_adjust = FIELD_GET(LTC4282_ILIM_ADJUST_MASK, reg_val);
+ *curr_lim_uv = ltc4282_curr_lim_uv[ilm_adjust];
+
+ st->in0_1_cache[LTC4282_CHAN_VSOURCE].en = FIELD_GET(LTC4282_VDD_MONITOR_MASK,
+ ilm_adjust);
+ if (!st->in0_1_cache[LTC4282_CHAN_VSOURCE].en) {
+ st->in0_1_cache[LTC4282_CHAN_VDD].en = true;
+ return regmap_read(st->map, LTC4282_VSOURCE_MAX,
+ &st->in0_1_cache[LTC4282_CHAN_VSOURCE].in_max_raw);
+ }
+
+ return regmap_read(st->map, LTC4282_VSOURCE_MAX,
+ &st->in0_1_cache[LTC4282_CHAN_VDD].in_max_raw);
+}
+
+/*
+ * 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 ltc4282_set_max_limits(struct ltc4282_state *st, u32 val_uv)
+{
+ int ret;
+
+ ret = ltc4282_write_voltage_byte(st, LTC4282_VSENSE_MAX, 40 * MILLI,
+ val_uv);
+ if (ret)
+ return ret;
+
+ /* Power is given by ISENSE * Vout. */
+ st->power_max = DIV_ROUND_CLOSEST(val_uv * DECA * MILLI, st->rsense) * st->vfs_out;
+ return ltc4282_write_power_byte(st, LTC4282_POWER_MAX, st->power_max);
+}
+
+static const char * const ltc4282_gpio1_modes[] = {
+ "power_bad", "power_good"
+};
+
+static const char * const ltc4282_gpio2_modes[] = {
+ "adc_input", "stress_fet"
+};
+
+static int ltc4282_gpio_setup(struct ltc4282_state *st, struct device *dev)
+{
+ const char *func;
+ int ret;
+
+ ret = device_property_read_string(dev, "adi,gpio1-mode", &func);
+ if (!ret) {
+ ret = match_string(ltc4282_gpio1_modes,
+ ARRAY_SIZE(ltc4282_gpio1_modes), func);
+ if (ret < 0)
+ return dev_err_probe(dev, ret,
+ "Invalid func(%s) for gpio1\n",
+ func);
+
+ ret = regmap_update_bits(st->map, LTC4282_GPIO_CONFIG,
+ LTC4282_GPIO_1_CONFIG_MASK,
+ FIELD_PREP(LTC4282_GPIO_1_CONFIG_MASK, ret));
+ if (ret)
+ return ret;
+ }
+
+ ret = device_property_read_string(dev, "adi,gpio2-mode", &func);
+ if (ret)
+ return 0;
+
+ ret = match_string(ltc4282_gpio2_modes, ARRAY_SIZE(ltc4282_gpio2_modes),
+ func);
+ if (ret < 0)
+ return dev_err_probe(dev, ret, "Invalid func(%s) for gpio2\n",
+ func);
+ if (!ret)
+ /* setting the bit to 1 cause the ADC to monitor GPIO2 */
+ return regmap_set_bits(st->map, LTC4282_ILIM_ADJUST,
+ LTC4282_GPIO_MODE_MASK);
+
+ return regmap_update_bits(st->map, LTC4282_GPIO_CONFIG,
+ LTC4282_GPIO_2_FET_STRESS_MASK,
+ FIELD_PREP(LTC4282_GPIO_2_FET_STRESS_MASK, 1));
+}
+
+static const char * const ltc4282_dividers[] = {
+ "external", "vdd_5_percent", "vdd_10_percent", "vdd_15_percent"
+};
+
+/* This maps the Vout full scale for the given Vin mode */
+static const u16 ltc4282_vfs_milli[] = { 5540, 8320, 16640, 33280 };
+
+static int ltc4282_setup(struct ltc4282_state *st, struct device *dev)
+{
+ u32 val, curr_lim_uv;
+ const char *divider;
+ int ret;
+
+ /* The part has an eeprom so let's get the needed defaults from it */
+ ret = ltc4282_get_defaults(st, &curr_lim_uv);
+ if (ret)
+ return ret;
+
+ ret = device_property_read_u32(dev, "adi,rsense-nano-ohms",
+ &st->rsense);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "Failed to read adi,rsense-nano-ohms\n");
+ if (st->rsense < CENTI)
+ return dev_err_probe(dev, -EINVAL,
+ "adi,rsense-nano-ohms too small (< %lu)\n",
+ CENTI);
+
+ /*
+ * 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,vin-mode-microvolt", &val);
+ if (!ret) {
+ switch (val) {
+ case 3300000:
+ st->vin_mode = LTC4282_VIN_3_3V;
+ break;
+ case 5000000:
+ st->vin_mode = LTC4282_VIN_5V;
+ break;
+ case 12000000:
+ st->vin_mode = LTC4282_VIN_12V;
+ break;
+ case 24000000:
+ st->vin_mode = LTC4282_VIN_24V;
+ break;
+ default:
+ return dev_err_probe(dev, -EINVAL,
+ "Invalid val(%u) for vin-mode-microvolt\n",
+ val);
+ }
+
+ ret = regmap_update_bits(st->map, LTC4282_CTRL_MSB,
+ LTC4282_CTRL_VIN_MODE_MASK,
+ FIELD_PREP(LTC4282_CTRL_VIN_MODE_MASK, st->vin_mode));
+ if (ret)
+ return ret;
+
+ /* Foldback mode should also be set to the input voltage */
+ ret = regmap_update_bits(st->map, LTC4282_ILIM_ADJUST,
+ LTC4282_FOLDBACK_MODE_MASK,
+ FIELD_PREP(LTC4282_FOLDBACK_MODE_MASK, st->vin_mode));
+ if (ret)
+ return ret;
+ }
+
+ st->vfs_out = ltc4282_vfs_milli[st->vin_mode];
+
+ ret = device_property_read_u32(dev, "adi,current-limit-sense-microvolt",
+ &curr_lim_uv);
+ if (!ret) {
+ int reg_val;
+
+ switch (val) {
+ case 12500:
+ reg_val = 0;
+ break;
+ case 15625:
+ reg_val = 1;
+ break;
+ case 18750:
+ reg_val = 2;
+ break;
+ case 21875:
+ reg_val = 3;
+ break;
+ case 25000:
+ reg_val = 4;
+ break;
+ case 28125:
+ reg_val = 5;
+ break;
+ case 31250:
+ reg_val = 6;
+ break;
+ case 34375:
+ reg_val = 7;
+ break;
+ default:
+ return dev_err_probe(dev, -EINVAL,
+ "Invalid val(%u) for adi,current-limit-microvolt\n",
+ val);
+ }
+
+ ret = regmap_update_bits(st->map, LTC4282_ILIM_ADJUST,
+ LTC4282_ILIM_ADJUST_MASK,
+ FIELD_PREP(LTC4282_ILIM_ADJUST_MASK, reg_val));
+ if (ret)
+ return ret;
+ }
+
+ ret = ltc4282_set_max_limits(st, curr_lim_uv);
+ if (ret)
+ return ret;
+
+ ret = device_property_read_string(dev, "adi,overvoltage-dividers",
+ ÷r);
+ if (!ret) {
+ int div = match_string(ltc4282_dividers,
+ ARRAY_SIZE(ltc4282_dividers), divider);
+ if (div < 0)
+ return dev_err_probe(dev, -EINVAL,
+ "Invalid val(%s) for adi,overvoltage-divider\n",
+ divider);
+
+ ret = regmap_update_bits(st->map, LTC4282_CTRL_MSB,
+ LTC4282_CTRL_OV_MODE_MASK,
+ FIELD_PREP(LTC4282_CTRL_OV_MODE_MASK, div));
+ }
+
+ ret = device_property_read_string(dev, "adi,undervoltage-dividers",
+ ÷r);
+ if (!ret) {
+ int div = match_string(ltc4282_dividers,
+ ARRAY_SIZE(ltc4282_dividers), divider);
+ if (div < 0)
+ return dev_err_probe(dev, -EINVAL,
+ "Invalid val(%s) for adi,undervoltage-divider\n",
+ divider);
+
+ ret = regmap_update_bits(st->map, LTC4282_CTRL_MSB,
+ LTC4282_CTRL_UV_MODE_MASK,
+ FIELD_PREP(LTC4282_CTRL_UV_MODE_MASK, div));
+ }
+
+ if (device_property_read_bool(dev, "adi,overcurrent-retry")) {
+ ret = regmap_set_bits(st->map, LTC4282_CTRL_LSB,
+ LTC4282_CTRL_OC_RETRY_MASK);
+ if (ret)
+ return ret;
+ }
+
+ if (device_property_read_bool(dev, "adi,overvoltage-retry-disable")) {
+ ret = regmap_clear_bits(st->map, LTC4282_CTRL_LSB,
+ LTC4282_CTRL_OV_RETRY_MASK);
+ if (ret)
+ return ret;
+ }
+
+ if (device_property_read_bool(dev, "adi,undervoltage-retry-disable")) {
+ ret = regmap_clear_bits(st->map, LTC4282_CTRL_LSB,
+ LTC4282_CTRL_UV_RETRY_MASK);
+ if (ret)
+ return ret;
+ }
+
+ if (device_property_read_bool(dev, "adi,fault-log-enable")) {
+ ret = regmap_set_bits(st->map, LTC4282_ADC_CTRL,
+ LTC4282_FAULT_LOG_EN_MASK);
+ if (ret)
+ return ret;
+ }
+
+ if (device_property_read_bool(dev, "adi,fault-log-enable")) {
+ ret = regmap_set_bits(st->map, LTC4282_ADC_CTRL, LTC4282_FAULT_LOG_EN_MASK);
+ if (ret)
+ return ret;
+ }
+
+ ret = device_property_read_u32(dev, "adi,fet-bad-timeout-ms", &val);
+ if (!ret) {
+ if (val > LTC4282_FET_BAD_MAX_TIMEOUT)
+ return dev_err_probe(dev, -EINVAL,
+ "Invalid value(%u) for adi,fet-bad-timeout-ms",
+ val);
+
+ ret = regmap_write(st->map, LTC4282_FET_BAD_FAULT_TIMEOUT, val);
+ if (ret)
+ return ret;
+ }
+
+ return ltc4282_gpio_setup(st, dev);
+}
+
+static bool ltc4282_readable_reg(struct device *dev, unsigned int reg)
+{
+ if (reg == LTC4282_RESERVED_1 || reg == LTC4282_RESERVED_2)
+ return false;
+
+ return true;
+}
+
+static bool ltc4282_writable_reg(struct device *dev, unsigned int reg)
+{
+ if (reg == LTC4282_STATUS_LSB || reg == LTC4282_STATUS_MSB)
+ return false;
+ if (reg == LTC4282_RESERVED_1 || reg == LTC4282_RESERVED_2)
+ return false;
+
+ return true;
+}
+
+static const struct regmap_config ltc4282_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+ .max_register = LTC4282_RESERVED_3,
+ .readable_reg = ltc4282_readable_reg,
+ .writeable_reg = ltc4282_writable_reg,
+};
+
+static const struct hwmon_channel_info * const ltc4282_info[] = {
+ HWMON_CHANNEL_INFO(in,
+ 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_ENABLE |
+ 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_LCRIT_ALARM |
+ HWMON_I_CRIT_ALARM | HWMON_I_ENABLE |
+ 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_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_I_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_I_RESET_HISTORY | HWMON_P_LABEL),
+ HWMON_CHANNEL_INFO(energy,
+ HWMON_E_ENABLE),
+ NULL
+};
+
+static const struct hwmon_ops ltc4282_hwmon_ops = {
+ .read = ltc4282_read,
+ .write = ltc4282_write,
+ .is_visible = ltc4282_is_visible,
+ .read_string = ltc4282_read_labels,
+};
+
+static const struct hwmon_chip_info ltc2947_chip_info = {
+ .ops = <c4282_hwmon_ops,
+ .info = ltc4282_info,
+};
+
+/* energy attributes are 6bytes wide so we need u64 */
+static SENSOR_DEVICE_ATTR_RO(energy1_input, ltc4282_energy, 0);
+/* power1_fault */
+static SENSOR_DEVICE_ATTR_RO(power1_good, ltc4282_status,
+ LTC4282_POWER_GOOD_MASK);
+/* FET faults */
+static SENSOR_DEVICE_ATTR_RO(fet_short_fault, ltc4282_status,
+ LTC4282_FET_SHORT_MASK);
+static SENSOR_DEVICE_ATTR_RO(fet_bad_fault, ltc4282_status,
+ LTC4282_FET_BAD_STATUS_MASK);
+/*
+ * Fault log failures. These faults might be important in systems where
+ * auto-retry is not enabled since they will cause the part to latch off until
+ * they are cleared. Typically that happens when the system admin is close
+ * enough so he can check what happened and manually clear the faults. Hence, we
+ * provide an attribute to clear all fauls at once while still capable of
+ * checking individual faults in debugfs.
+ */
+static SENSOR_DEVICE_ATTR_WO(fault_logs_reset, ltc4282_clear_faults, 0);
+
+static struct attribute *ltc4282_attrs[] = {
+ &sensor_dev_attr_energy1_input.dev_attr.attr,
+ &sensor_dev_attr_power1_good.dev_attr.attr,
+ &sensor_dev_attr_fet_bad_fault.dev_attr.attr,
+ &sensor_dev_attr_fet_short_fault.dev_attr.attr,
+ &sensor_dev_attr_fault_logs_reset.dev_attr.attr,
+ NULL
+};
+ATTRIBUTE_GROUPS(ltc4282);
+
+static int ltc4282_show_fault_log(void *arg, u64 *val, u32 mask)
+{
+ struct ltc4282_state *st = arg;
+ long alarm;
+ int ret;
+
+ ret = ltc4282_read_alarm(st, LTC4282_FAULT_LOG, mask, &alarm);
+ if (ret)
+ return ret;
+
+ *val = alarm;
+
+ return 0;
+}
+
+static int ltc4282_show_curr1_crit_fault_log(void *arg, u64 *val)
+{
+ return ltc4282_show_fault_log(arg, val, LTC4282_OC_FAULT_MASK);
+}
+DEFINE_DEBUGFS_ATTRIBUTE(ltc4282_curr1_crit_fault_log,
+ ltc4282_show_curr1_crit_fault_log, NULL, "%llu\n");
+
+static int ltc4282_show_in1_lcrit_fault_log(void *arg, u64 *val)
+{
+ return ltc4282_show_fault_log(arg, val, LTC4282_UV_FAULT_MASK);
+}
+DEFINE_DEBUGFS_ATTRIBUTE(ltc4282_in1_lcrit_fault_log,
+ ltc4282_show_in1_lcrit_fault_log, NULL, "%llu\n");
+
+static int ltc4282_show_in1_crit_fault_log(void *arg, u64 *val)
+{
+ return ltc4282_show_fault_log(arg, val, LTC4282_OV_FAULT_MASK);
+}
+DEFINE_DEBUGFS_ATTRIBUTE(ltc4282_in1_crit_fault_log,
+ ltc4282_show_in1_crit_fault_log, NULL, "%llu\n");
+
+static int ltc4282_show_fet_bad_fault_log(void *arg, u64 *val)
+{
+ return ltc4282_show_fault_log(arg, val, LTC4282_FET_BAD_FAULT_MASK);
+}
+DEFINE_DEBUGFS_ATTRIBUTE(ltc4282_fet_bad_fault_log,
+ ltc4282_show_fet_bad_fault_log, NULL, "%llu\n");
+
+static int ltc4282_show_fet_short_fault_log(void *arg, u64 *val)
+{
+ return ltc4282_show_fault_log(arg, val, LTC4282_FET_SHORT_FAULT_MASK);
+}
+DEFINE_DEBUGFS_ATTRIBUTE(ltc4282_fet_short_fault_log,
+ ltc4282_show_fet_short_fault_log, NULL, "%llu\n");
+
+static int ltc4282_show_power1_bad_fault_log(void *arg, u64 *val)
+{
+ return ltc4282_show_fault_log(arg, val, LTC4282_POWER_BAD_FAULT_MASK);
+}
+DEFINE_DEBUGFS_ATTRIBUTE(ltc4282_power1_bad_fault_log,
+ ltc4282_show_power1_bad_fault_log, NULL, "%llu\n");
+
+static void ltc4282_debugfs_remove(void *dir)
+{
+ debugfs_remove_recursive(dir);
+}
+
+static void ltc4282_debugfs_init(struct ltc4282_state *st,
+ struct i2c_client *i2c,
+ const struct device *hwmon)
+{
+ const char *debugfs_name;
+ struct dentry *dentry;
+ int ret;
+
+ if (!IS_ENABLED(CONFIG_DEBUG_FS))
+ return;
+
+ debugfs_name = devm_kasprintf(&i2c->dev, GFP_KERNEL, "%s-%s",
+ i2c->name, dev_name(hwmon));
+ if (!debugfs_name)
+ return;
+
+ dentry = debugfs_create_dir(debugfs_name, NULL);
+ if (IS_ERR(dentry))
+ return;
+
+ ret = devm_add_action_or_reset(&i2c->dev, ltc4282_debugfs_remove,
+ dentry);
+ if (ret)
+ return;
+
+ debugfs_create_file_unsafe("power1_bad_fault_log", 0400, dentry, st,
+ <c4282_power1_bad_fault_log);
+ debugfs_create_file_unsafe("fet_short_fault_log", 0400, dentry, st,
+ <c4282_fet_short_fault_log);
+ debugfs_create_file_unsafe("fet_bad_fault_log", 0400, dentry, st,
+ <c4282_fet_bad_fault_log);
+ debugfs_create_file_unsafe("in1_crit_fault_log", 0400, dentry, st,
+ <c4282_in1_crit_fault_log);
+ debugfs_create_file_unsafe("in1_lcrit_fault_log", 0400, dentry, st,
+ <c4282_in1_lcrit_fault_log);
+ debugfs_create_file_unsafe("curr1_crit_fault_log", 0400, dentry, st,
+ <c4282_curr1_crit_fault_log);
+}
+
+static int ltc4282_probe(struct i2c_client *i2c)
+{
+ struct device *dev = &i2c->dev, *hwmon;
+ struct ltc4282_state *st;
+ int ret;
+
+ st = devm_kzalloc(dev, sizeof(*st), GFP_KERNEL);
+ if (!st)
+ return dev_err_probe(dev, -ENOMEM,
+ "Failed to allocate memory\n");
+
+ st->map = devm_regmap_init_i2c(i2c, <c4282_regmap_config);
+ if (IS_ERR(st->map))
+ return dev_err_probe(dev, PTR_ERR(st->map),
+ "failed regmap init\n");
+
+ /* Soft reset */
+ ret = regmap_set_bits(st->map, LTC4282_ADC_CTRL, LTC4282_RESET_MASK);
+ if (ret)
+ return ret;
+
+ /* Yes, it's big but it is as specified in the datasheet */
+ msleep(3200);
+
+ ret = ltc428_clks_setup(st, dev);
+ if (ret)
+ return ret;
+
+ ret = ltc4282_setup(st, dev);
+ if (ret)
+ return ret;
+
+ mutex_init(&st->lock);
+ hwmon = devm_hwmon_device_register_with_info(dev, "ltc4282", st,
+ <c2947_chip_info,
+ ltc4282_groups);
+ if (IS_ERR(hwmon))
+ return PTR_ERR(hwmon);
+
+ ltc4282_debugfs_init(st, i2c, hwmon);
+
+ return 0;
+}
+
+static const struct of_device_id ltc4282_of_match[] = {
+ { .compatible = "adi,ltc4282" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, ltc4282_of_match);
+
+static struct i2c_driver ltc4282_driver = {
+ .driver = {
+ .name = "ltc4282",
+ .of_match_table = ltc4282_of_match,
+ },
+ .probe = ltc4282_probe,
+};
+module_i2c_driver(ltc4282_driver);
+
+MODULE_AUTHOR("Nuno Sa <nuno.sa@analog.com>");
+MODULE_DESCRIPTION("LTC4282 I2C High Current Hot Swap Controller");
+MODULE_LICENSE("GPL");