[PATCH 1/3] hwmon: ltc2992: Add support

From: alexandru.tachici
Date: Thu Oct 29 2020 - 05:46:08 EST

From: Alexandru Tachici <alexandru.tachici@xxxxxxxxxx>

LTC2992 is a rail-to-rail system monitor that
measures current, voltage, and power of two supplies.

Two ADCs simultaneously measure each supply’s current.
A third ADC monitors the input voltages and four
auxiliary external voltages.

Signed-off-by: Alexandru Tachici <alexandru.tachici@xxxxxxxxxx>
---
Documentation/hwmon/index.rst | 1 +
Documentation/hwmon/ltc2992.rst | 51 +++
drivers/hwmon/Kconfig | 11 +
drivers/hwmon/Makefile | 1 +
drivers/hwmon/ltc2992.c | 735 ++++++++++++++++++++++++++++++++
5 files changed, 799 insertions(+)
create mode 100644 Documentation/hwmon/ltc2992.rst
create mode 100644 drivers/hwmon/ltc2992.c

diff --git a/Documentation/hwmon/index.rst b/Documentation/hwmon/index.rst
index e6b91ab12978..f759d70ae9fd 100644
--- a/Documentation/hwmon/index.rst
+++ b/Documentation/hwmon/index.rst
@@ -104,6 +104,7 @@ Hardware Monitoring Kernel Drivers
ltc2947
ltc2978
ltc2990
+ ltc2992
ltc3815
ltc4151
ltc4215
diff --git a/Documentation/hwmon/ltc2992.rst b/Documentation/hwmon/ltc2992.rst
new file mode 100644
index 000000000000..1dd48ef9f655
--- /dev/null
+++ b/Documentation/hwmon/ltc2992.rst
@@ -0,0 +1,51 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+Kernel driver ltc2992
+=====================
+
+Supported chips:
+ * Linear Technology LTC2992
+ Prefix: 'ltc2992'
+ Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ltc2992.pdf
+
+Author: Alexandru Tachici <alexandru.tachici@xxxxxxxxxx>
+
+
+Description
+-----------
+
+This driver supports hardware monitoring for Linear Technology LTC2992 power monitor.
+
+LTC2992 is is a rail-to-rail system monitor that measures current,
+voltage, and power of two supplies.
+
+Two ADCs simultaneously measure each supply’s current. A third ADC monitors
+the input voltages and four auxiliary external voltages.
+
+
+Sysfs entries
+-------------
+
+The following attributes are supported. Limits are read-write,
+all other attributes are read-only.
+
+inX_input Measured voltage.
+inX_min Minimum voltage.
+inX_max Maximum voltage.
+inX_min_alarm Voltage low alarm.
+inX_max_alarm Voltage high alarm.
+inX_alarm An overvoltage or undervoltage occured. Cleared on read.
+
+currX_input Measured current.
+currX_min Minimum current.
+currX_max Maximum current.
+currX_min_alarm Current low alarm.
+currX_max_alarm Current high alarm.
+currX_alarm An overvoltage or undervoltage occured. Cleared on read.
+
+powerX_input Measured power.
+powerX_min Minimum power.
+powerX_max Maximum power.
+powerX_min_alarm Power low alarm.
+powerX_max_alarm Power high alarm.
+powerX_alarm An overpower or underpower occured. Cleared on read.
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index a850e4f0e0bd..bf9e387270d6 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -858,6 +858,17 @@ config SENSORS_LTC2990
This driver can also be built as a module. If so, the module will
be called ltc2990.

+config SENSORS_LTC2992
+ tristate "Linear Technology LTC2992"
+ depends on I2C
+ help
+ If you say yes here you get support for Linear Technology LTC2992
+ I2C System Monitor. The LTC2992 measures current, voltage, and
+ power of two supplies.
+
+ This driver can also be built as a module. If so, the module will
+ be called ltc2992.
+
config SENSORS_LTC4151
tristate "Linear Technology LTC4151"
depends on I2C
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index 9db2903b61e5..d6172c4807c4 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -118,6 +118,7 @@ obj-$(CONFIG_SENSORS_LTC2947) += ltc2947-core.o
obj-$(CONFIG_SENSORS_LTC2947_I2C) += ltc2947-i2c.o
obj-$(CONFIG_SENSORS_LTC2947_SPI) += ltc2947-spi.o
obj-$(CONFIG_SENSORS_LTC2990) += ltc2990.o
+obj-$(CONFIG_SENSORS_LTC2992) += ltc2992.o
obj-$(CONFIG_SENSORS_LTC4151) += ltc4151.o
obj-$(CONFIG_SENSORS_LTC4215) += ltc4215.o
obj-$(CONFIG_SENSORS_LTC4222) += ltc4222.o
diff --git a/drivers/hwmon/ltc2992.c b/drivers/hwmon/ltc2992.c
new file mode 100644
index 000000000000..940d92b4a1d0
--- /dev/null
+++ b/drivers/hwmon/ltc2992.c
@@ -0,0 +1,735 @@
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+/*
+ * LTC2992 - Dual Wide Range Power Monitor
+ *
+ * Copyright 2020 Analog Devices Inc.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/bits.h>
+#include <linux/err.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/property.h>
+#include <linux/regmap.h>
+
+#define LTC2992_CTRLB 0x01
+#define LTC2992_FAULT1 0x03
+#define LTC2992_POWER1 0x05
+#define LTC2992_POWER1_MAX 0x08
+#define LTC2992_POWER1_MIN 0x0B
+#define LTC2992_POWER1_MAX_THRESH 0x0E
+#define LTC2992_POWER1_MIN_THRESH 0x11
+#define LTC2992_DSENSE1 0x14
+#define LTC2992_DSENSE1_MAX 0x16
+#define LTC2992_DSENSE1_MIN 0x18
+#define LTC2992_DSENSE1_MAX_THRESH 0x1A
+#define LTC2992_DSENSE1_MIN_THRESH 0x1C
+#define LTC2992_SENSE1 0x1E
+#define LTC2992_SENSE1_MAX 0x20
+#define LTC2992_SENSE1_MIN 0x22
+#define LTC2992_SENSE1_MAX_THRESH 0x24
+#define LTC2992_SENSE1_MIN_THRESH 0x26
+#define LTC2992_G1 0x28
+#define LTC2992_G1_MAX 0x2A
+#define LTC2992_G1_MIN 0x2C
+#define LTC2992_G1_MAX_THRESH 0x2E
+#define LTC2992_G1_MIN_THRESH 0x30
+#define LTC2992_FAULT2 0x35
+#define LTC2992_G2 0x5A
+#define LTC2992_G2_MAX 0x5C
+#define LTC2992_G2_MIN 0x5E
+#define LTC2992_G2_MAX_THRESH 0x60
+#define LTC2992_G2_MIN_THRESH 0x62
+#define LTC2992_G3 0x64
+#define LTC2992_G3_MAX 0x66
+#define LTC2992_G3_MIN 0x68
+#define LTC2992_G3_MAX_THRESH 0x6A
+#define LTC2992_G3_MIN_THRESH 0x6C
+#define LTC2992_G4 0x6E
+#define LTC2992_G4_MAX 0x70
+#define LTC2992_G4_MIN 0x72
+#define LTC2992_G4_MAX_THRESH 0x74
+#define LTC2992_G4_MIN_THRESH 0x76
+#define LTC2992_FAULT3 0x92
+
+#define LTC2992_POWER(x) (LTC2992_POWER1 + ((x) * 0x32))
+#define LTC2992_POWER_MAX(x) (LTC2992_POWER1_MAX + ((x) * 0x32))
+#define LTC2992_POWER_MIN(x) (LTC2992_POWER1_MIN + ((x) * 0x32))
+#define LTC2992_POWER_MAX_THRESH(x) (LTC2992_POWER1_MAX_THRESH + ((x) * 0x32))
+#define LTC2992_POWER_MIN_THRESH(x) (LTC2992_POWER1_MIN_THRESH + ((x) * 0x32))
+#define LTC2992_DSENSE(x) (LTC2992_DSENSE1 + ((x) * 0x32))
+#define LTC2992_DSENSE_MAX(x) (LTC2992_DSENSE1_MAX + ((x) * 0x32))
+#define LTC2992_DSENSE_MIN(x) (LTC2992_DSENSE1_MIN + ((x) * 0x32))
+#define LTC2992_DSENSE_MAX_THRESH(x) (LTC2992_DSENSE1_MAX_THRESH + ((x) * 0x32))
+#define LTC2992_DSENSE_MIN_THRESH(x) (LTC2992_DSENSE1_MIN_THRESH + ((x) * 0x32))
+#define LTC2992_SENSE(x) (LTC2992_SENSE1 + ((x) * 0x32))
+#define LTC2992_SENSE_MAX(x) (LTC2992_SENSE1_MAX + ((x) * 0x32))
+#define LTC2992_SENSE_MIN(x) (LTC2992_SENSE1_MIN + ((x) * 0x32))
+#define LTC2992_SENSE_MAX_THRESH(x) (LTC2992_SENSE1_MAX_THRESH + ((x) * 0x32))
+#define LTC2992_SENSE_MIN_THRESH(x) (LTC2992_SENSE1_MIN_THRESH + ((x) * 0x32))
+#define LTC2992_POWER_FAULT(x) (LTC2992_FAULT1 + ((x) * 0x32))
+#define LTC2992_SENSE_FAULT(x) (LTC2992_FAULT1 + ((x) * 0x32))
+#define LTC2992_DSENSE_FAULT(x) (LTC2992_FAULT1 + ((x) * 0x32))
+
+/* FAULT1 FAULT2 registers common bitfields */
+#define LTC2992_POWER_FAULT_MSK GENMASK(7, 6)
+#define LTC2992_DSENSE_FAULT_MSK GENMASK(5, 4)
+#define LTC2992_SENSE_FAULT_MSK GENMASK(3, 2)
+
+/* FAULT1 bitfields */
+#define LTC2992_GPIO1_FAULT_MSK GENMASK(1, 0)
+
+/* FAULT2 bitfields */
+#define LTC2992_GPIO2_FAULT_MSK GENMASK(1, 0)
+
+/* FAULT3 bitfields */
+#define LTC2992_GPIO3_FAULT_MSK GENMASK(7, 6)
+#define LTC2992_GPIO4_FAULT_MSK GENMASK(5, 4)
+
+#define LTC2992_IADC_NANOV_LSB 12500
+#define LTC2992_VADC_UV_LSB 25000
+#define LTC2992_VADC_GPIO_UV_LSB 500
+
+struct ltc2992_state {
+ struct i2c_client *client;
+ struct regmap *regmap;
+ u32 r_sense_uohm[2];
+};
+
+struct ltc2992_gpio_regs {
+ u8 data;
+ u8 max;
+ u8 min;
+ u8 max_thresh;
+ u8 min_thresh;
+ u8 alarm;
+ u8 alarm_msk;
+};
+
+static const struct ltc2992_gpio_regs ltc2992_gpio_addr_map[] = {
+ {
+ .data = LTC2992_G1,
+ .max = LTC2992_G1_MAX,
+ .min = LTC2992_G1_MIN,
+ .max_thresh = LTC2992_G1_MAX_THRESH,
+ .min_thresh = LTC2992_G1_MIN_THRESH,
+ .alarm = LTC2992_FAULT1,
+ .alarm_msk = LTC2992_GPIO1_FAULT_MSK,
+ },
+ {
+ .data = LTC2992_G2,
+ .max = LTC2992_G2_MAX,
+ .min = LTC2992_G2_MIN,
+ .max_thresh = LTC2992_G2_MAX_THRESH,
+ .min_thresh = LTC2992_G2_MIN_THRESH,
+ .alarm = LTC2992_FAULT2,
+ .alarm_msk = LTC2992_GPIO2_FAULT_MSK,
+ },
+ {
+ .data = LTC2992_G3,
+ .max = LTC2992_G3_MAX,
+ .min = LTC2992_G3_MIN,
+ .max_thresh = LTC2992_G3_MAX_THRESH,
+ .min_thresh = LTC2992_G3_MIN_THRESH,
+ .alarm = LTC2992_FAULT3,
+ .alarm_msk = LTC2992_GPIO3_FAULT_MSK,
+ },
+ {
+ .data = LTC2992_G4,
+ .max = LTC2992_G4_MAX,
+ .min = LTC2992_G4_MIN,
+ .max_thresh = LTC2992_G4_MAX_THRESH,
+ .min_thresh = LTC2992_G4_MIN_THRESH,
+ .alarm = LTC2992_FAULT3,
+ .alarm_msk = LTC2992_GPIO4_FAULT_MSK,
+ },
+};
+
+static int ltc2992_read_reg(struct ltc2992_state *st, u8 addr, const u8 reg_len, u32 *val)
+{
+ u8 regvals[4];
+ int ret;
+ int i;
+
+ ret = regmap_bulk_read(st->regmap, addr, regvals, reg_len);
+ if (ret < 0)
+ return ret;
+
+ *val = 0;
+ for (i = 0; i < reg_len; i++)
+ *val |= regvals[reg_len - i - 1] << (i * 8);
+
+ return 0;
+}
+
+static int ltc2992_write_reg(struct ltc2992_state *st, u8 addr, const u8 reg_len, u32 val)
+{
+ u8 regvals[4];
+ int i;
+
+ for (i = 0; i < reg_len; i++)
+ regvals[reg_len - i - 1] = (val >> (i * 8)) & 0xFF;
+
+ return regmap_bulk_write(st->regmap, addr, regvals, reg_len);
+}
+
+static umode_t ltc2992_is_visible(const void *data, enum hwmon_sensor_types type, u32 attr,
+ int channel)
+{
+ const struct ltc2992_state *st = data;
+
+ switch (type) {
+ case hwmon_in:
+ switch (attr) {
+ case hwmon_in_input:
+ case hwmon_in_min:
+ case hwmon_in_max:
+ case hwmon_in_alarm:
+ return 0444;
+ case hwmon_in_min_alarm:
+ case hwmon_in_max_alarm:
+ return 0644;
+ }
+ break;
+ case hwmon_curr:
+ switch (attr) {
+ case hwmon_curr_input:
+ case hwmon_curr_min:
+ case hwmon_curr_max:
+ case hwmon_curr_alarm:
+ if (st->r_sense_uohm[channel])
+ return 0444;
+ break;
+ case hwmon_curr_min_alarm:
+ case hwmon_curr_max_alarm:
+ if (st->r_sense_uohm[channel])
+ return 0644;
+ break;
+ }
+ break;
+ case hwmon_power:
+ switch (attr) {
+ case hwmon_power_input:
+ case hwmon_power_min:
+ case hwmon_power_max:
+ case hwmon_power_alarm:
+ if (st->r_sense_uohm[channel])
+ return 0444;
+ break;
+ case hwmon_power_min_alarm:
+ case hwmon_power_max_alarm:
+ if (st->r_sense_uohm[channel])
+ return 0644;
+ break;
+ }
+ break;
+ default:
+ break;
+ }
+
+ return 0;
+}
+
+static int ltc2992_get_voltage(struct ltc2992_state *st, u32 reg, u32 scale, long *val)
+{
+ u32 reg_val;
+ int ret;
+
+ ret = ltc2992_read_reg(st, reg, 2, &reg_val);
+ if (ret < 0)
+ return ret;
+
+ reg_val = reg_val >> 4;
+ *val = DIV_ROUND_CLOSEST(reg_val * scale, 1000);
+
+ return 0;
+}
+
+static int ltc2992_set_voltage(struct ltc2992_state *st, u32 reg, u32 scale, long val)
+{
+ val = DIV_ROUND_CLOSEST(val * 1000, scale);
+ val = val << 4;
+
+ return ltc2992_write_reg(st, reg, 2, val);
+}
+
+static int ltc2992_read_gpio_alarm(struct ltc2992_state *st, int nr_gpio, long *val)
+{
+ u32 reg_val;
+ int ret;
+
+ ret = ltc2992_read_reg(st, ltc2992_gpio_addr_map[nr_gpio].alarm, 1, &reg_val);
+ if (ret < 0)
+ return ret;
+
+ *val = !!(reg_val & ltc2992_gpio_addr_map[nr_gpio].alarm_msk);
+
+ reg_val &= ~ltc2992_gpio_addr_map[nr_gpio].alarm_msk;
+ return ltc2992_write_reg(st, ltc2992_gpio_addr_map[nr_gpio].alarm, 1, reg_val);
+}
+
+static int ltc2992_read_gpios_in(struct device *dev, u32 attr, int nr_gpio, long *val)
+{
+ struct ltc2992_state *st = dev_get_drvdata(dev);
+ u32 reg;
+
+ switch (attr) {
+ case hwmon_in_input:
+ reg = ltc2992_gpio_addr_map[nr_gpio].data;
+ break;
+ case hwmon_in_min:
+ reg = ltc2992_gpio_addr_map[nr_gpio].min;
+ break;
+ case hwmon_in_max:
+ reg = ltc2992_gpio_addr_map[nr_gpio].max;
+ break;
+ case hwmon_in_min_alarm:
+ reg = ltc2992_gpio_addr_map[nr_gpio].min_thresh;
+ break;
+ case hwmon_in_max_alarm:
+ reg = ltc2992_gpio_addr_map[nr_gpio].max_thresh;
+ break;
+ case hwmon_in_alarm:
+ return ltc2992_read_gpio_alarm(st, nr_gpio, val);
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ return ltc2992_get_voltage(st, reg, LTC2992_VADC_GPIO_UV_LSB, val);
+}
+
+static int ltc2992_read_in(struct device *dev, u32 attr, int channel, long *val)
+{
+ struct ltc2992_state *st = dev_get_drvdata(dev);
+ u32 reg_val;
+ u32 reg;
+ int ret;
+
+ if (channel > 1)
+ return ltc2992_read_gpios_in(dev, attr, channel - 2, val);
+
+ switch (attr) {
+ case hwmon_in_input:
+ reg = LTC2992_SENSE(channel);
+ break;
+ case hwmon_in_min:
+ reg = LTC2992_SENSE_MIN(channel);
+ break;
+ case hwmon_in_max:
+ reg = LTC2992_SENSE_MAX(channel);
+ break;
+ case hwmon_in_min_alarm:
+ reg = LTC2992_SENSE_MIN_THRESH(channel);
+ break;
+ case hwmon_in_max_alarm:
+ reg = LTC2992_SENSE_MAX_THRESH(channel);
+ break;
+ case hwmon_in_alarm:
+ ret = ltc2992_read_reg(st, LTC2992_SENSE_FAULT(channel), 1, &reg_val);
+ if (ret < 0)
+ return ret;
+
+ *val = !!(reg_val & LTC2992_SENSE_FAULT_MSK);
+
+ reg_val &= ~LTC2992_SENSE_FAULT_MSK;
+ return ltc2992_write_reg(st, LTC2992_SENSE_FAULT(channel), 1, reg_val);
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ return ltc2992_get_voltage(st, reg, LTC2992_VADC_UV_LSB, val);
+}
+
+static int ltc2992_get_current(struct ltc2992_state *st, u32 reg, u32 channel, long *val)
+{
+ u32 reg_val;
+ int ret;
+
+ ret = ltc2992_read_reg(st, reg, 2, &reg_val);
+ if (ret < 0)
+ return ret;
+
+ reg_val = reg_val >> 4;
+ *val = DIV_ROUND_CLOSEST(reg_val * LTC2992_IADC_NANOV_LSB, st->r_sense_uohm[channel]);
+
+ return 0;
+}
+
+static int ltc2992_set_current(struct ltc2992_state *st, u32 reg, u32 channel, long val)
+{
+ u32 reg_val;
+
+ reg_val = DIV_ROUND_CLOSEST(val * st->r_sense_uohm[channel], LTC2992_IADC_NANOV_LSB);
+ reg_val = reg_val << 4;
+
+ return ltc2992_write_reg(st, reg, 2, reg_val);
+}
+
+static int ltc2992_read_curr(struct device *dev, u32 attr, int channel, long *val)
+{
+ struct ltc2992_state *st = dev_get_drvdata(dev);
+ u32 reg_val;
+ u32 reg;
+ int ret;
+
+ switch (attr) {
+ case hwmon_curr_input:
+ reg = LTC2992_DSENSE(channel);
+ break;
+ case hwmon_curr_min:
+ reg = LTC2992_DSENSE_MIN(channel);
+ break;
+ case hwmon_curr_max:
+ reg = LTC2992_DSENSE_MAX(channel);
+ break;
+ case hwmon_curr_min_alarm:
+ reg = LTC2992_DSENSE_MIN_THRESH(channel);
+ break;
+ case hwmon_curr_max_alarm:
+ reg = LTC2992_DSENSE_MAX_THRESH(channel);
+ break;
+ case hwmon_curr_alarm:
+ ret = ltc2992_read_reg(st, LTC2992_DSENSE_FAULT(channel), 1, &reg_val);
+ if (ret < 0)
+ return ret;
+
+ *val = !!(reg_val & LTC2992_DSENSE_FAULT_MSK);
+
+ reg_val &= ~LTC2992_DSENSE_FAULT_MSK;
+ return ltc2992_write_reg(st, LTC2992_DSENSE_FAULT(channel), 1, reg_val);
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ return ltc2992_get_current(st, reg, channel, val);
+}
+
+static int ltc2992_get_power(struct ltc2992_state *st, u32 reg, u32 channel, long *val)
+{
+ u32 reg_val;
+ int ret;
+
+ ret = ltc2992_read_reg(st, reg, 3, &reg_val);
+ if (ret < 0)
+ return ret;
+
+ *val = mul_u64_u32_div(reg_val, LTC2992_VADC_UV_LSB * LTC2992_IADC_NANOV_LSB,
+ st->r_sense_uohm[channel] * 1000);
+
+ return 0;
+}
+
+static int ltc2992_set_power(struct ltc2992_state *st, u32 reg, u32 channel, long val)
+{
+ u32 reg_val;
+
+ reg_val = mul_u64_u32_div(val, st->r_sense_uohm[channel] * 1000,
+ LTC2992_VADC_UV_LSB * LTC2992_IADC_NANOV_LSB);
+
+ return ltc2992_write_reg(st, reg, 3, reg_val);
+}
+
+static int ltc2992_read_power(struct device *dev, u32 attr, int channel, long *val)
+{
+ struct ltc2992_state *st = dev_get_drvdata(dev);
+ u32 reg_val;
+ u32 reg;
+ int ret;
+
+ switch (attr) {
+ case hwmon_power_input:
+ reg = LTC2992_POWER(channel);
+ break;
+ case hwmon_power_min:
+ reg = LTC2992_POWER_MIN(channel);
+ break;
+ case hwmon_power_max:
+ reg = LTC2992_POWER_MAX(channel);
+ break;
+ case hwmon_power_min_alarm:
+ reg = LTC2992_POWER_MIN_THRESH(channel);
+ break;
+ case hwmon_power_max_alarm:
+ reg = LTC2992_POWER_MAX_THRESH(channel);
+ break;
+ case hwmon_power_alarm:
+ ret = ltc2992_read_reg(st, LTC2992_POWER_FAULT(channel), 1, &reg_val);
+ if (ret < 0)
+ return ret;
+
+ *val = !!(reg_val & LTC2992_POWER_FAULT_MSK);
+
+ reg_val &= ~LTC2992_POWER_FAULT_MSK;
+ return ltc2992_write_reg(st, LTC2992_POWER_FAULT(channel), 1, reg_val);
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ return ltc2992_get_power(st, reg, channel, val);
+}
+
+static int ltc2992_read(struct device *dev, enum hwmon_sensor_types type, u32 attr, int channel,
+ long *val)
+{
+ switch (type) {
+ case hwmon_in:
+ return ltc2992_read_in(dev, attr, channel, val);
+ case hwmon_curr:
+ return ltc2992_read_curr(dev, attr, channel, val);
+ case hwmon_power:
+ return ltc2992_read_power(dev, attr, channel, val);
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
+static int ltc2992_write_curr(struct device *dev, u32 attr, int channel, long val)
+{
+ struct ltc2992_state *st = dev_get_drvdata(dev);
+ u32 reg = 0;
+
+ switch (attr) {
+ case hwmon_curr_min_alarm:
+ reg = LTC2992_DSENSE_MIN_THRESH(channel);
+ break;
+ case hwmon_curr_max_alarm:
+ reg = LTC2992_DSENSE_MAX_THRESH(channel);
+ break;
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ return ltc2992_set_current(st, reg, channel, val);
+}
+
+static int ltc2992_write_gpios_in(struct device *dev, u32 attr, int nr_gpio, long val)
+{
+ struct ltc2992_state *st = dev_get_drvdata(dev);
+ u32 reg;
+
+ switch (attr) {
+ case hwmon_in_min_alarm:
+ reg = ltc2992_gpio_addr_map[nr_gpio].min_thresh;
+ break;
+ case hwmon_in_max_alarm:
+ reg = ltc2992_gpio_addr_map[nr_gpio].max_thresh;
+ break;
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ return ltc2992_set_voltage(st, reg, LTC2992_VADC_GPIO_UV_LSB, val);
+}
+
+static int ltc2992_write_in(struct device *dev, u32 attr, int channel, long val)
+{
+ struct ltc2992_state *st = dev_get_drvdata(dev);
+ u32 reg = 0;
+
+ if (channel > 1)
+ return ltc2992_write_gpios_in(dev, attr, channel - 2, val);
+
+ switch (attr) {
+ case hwmon_curr_min_alarm:
+ reg = LTC2992_SENSE_MIN_THRESH(channel);
+ break;
+ case hwmon_curr_max_alarm:
+ reg = LTC2992_SENSE_MAX_THRESH(channel);
+ break;
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ return ltc2992_set_voltage(st, reg, LTC2992_VADC_UV_LSB, val);
+}
+
+static int ltc2992_write_power(struct device *dev, u32 attr, int channel, long val)
+{
+ struct ltc2992_state *st = dev_get_drvdata(dev);
+ u32 reg = 0;
+
+ switch (attr) {
+ case hwmon_power_min_alarm:
+ reg = LTC2992_POWER_MIN_THRESH(channel);
+ break;
+ case hwmon_power_max_alarm:
+ reg = LTC2992_POWER_MAX_THRESH(channel);
+ break;
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ return ltc2992_set_power(st, reg, channel, val);
+}
+
+static int ltc2992_write(struct device *dev, enum hwmon_sensor_types type, u32 attr, int channel,
+ long val)
+{
+ switch (type) {
+ case hwmon_in:
+ return ltc2992_write_in(dev, attr, channel, val);
+ case hwmon_curr:
+ return ltc2992_write_curr(dev, attr, channel, val);
+ case hwmon_power:
+ return ltc2992_write_power(dev, attr, channel, val);
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
+static const struct hwmon_ops ltc2992_hwmon_ops = {
+ .is_visible = ltc2992_is_visible,
+ .read = ltc2992_read,
+ .write = ltc2992_write,
+};
+
+static const u32 ltc2992_in_config[] = {
+ HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_MIN_ALARM |
+ HWMON_I_MAX_ALARM | HWMON_I_ALARM,
+ HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_MIN_ALARM |
+ HWMON_I_MAX_ALARM | HWMON_I_ALARM,
+ HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_MIN_ALARM |
+ HWMON_I_MAX_ALARM | HWMON_I_ALARM,
+ HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_MIN_ALARM |
+ HWMON_I_MAX_ALARM | HWMON_I_ALARM,
+ HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_MIN_ALARM |
+ HWMON_I_MAX_ALARM | HWMON_I_ALARM,
+ HWMON_I_INPUT | HWMON_I_MIN | HWMON_I_MAX | HWMON_I_MIN_ALARM |
+ HWMON_I_MAX_ALARM | HWMON_I_ALARM,
+ 0
+};
+
+static const struct hwmon_channel_info ltc2992_in = {
+ .type = hwmon_in,
+ .config = ltc2992_in_config,
+};
+
+static const u32 ltc2992_curr_config[] = {
+ HWMON_C_INPUT | HWMON_C_MIN | HWMON_C_MAX | HWMON_C_MIN_ALARM | HWMON_C_MAX_ALARM |
+ HWMON_C_ALARM,
+ HWMON_C_INPUT | HWMON_C_MIN | HWMON_C_MAX | HWMON_C_MIN_ALARM | HWMON_C_MAX_ALARM |
+ HWMON_C_ALARM,
+ 0
+};
+
+static const struct hwmon_channel_info ltc2992_curr = {
+ .type = hwmon_curr,
+ .config = ltc2992_curr_config,
+};
+
+static const u32 ltc2992_power_config[] = {
+ HWMON_P_INPUT | HWMON_P_MIN | HWMON_P_MAX | HWMON_P_MIN_ALARM | HWMON_P_MAX_ALARM |
+ HWMON_P_ALARM,
+ HWMON_P_INPUT | HWMON_P_MIN | HWMON_P_MAX | HWMON_P_MIN_ALARM | HWMON_P_MAX_ALARM |
+ HWMON_P_ALARM,
+ 0
+};
+
+static const struct hwmon_channel_info ltc2992_power = {
+ .type = hwmon_power,
+ .config = ltc2992_power_config,
+};
+
+static const struct hwmon_channel_info *ltc2992_info[] = {
+ &ltc2992_in,
+ &ltc2992_curr,
+ &ltc2992_power,
+ NULL
+};
+
+static const struct hwmon_chip_info ltc2992_chip_info = {
+ .ops = &ltc2992_hwmon_ops,
+ .info = ltc2992_info,
+};
+
+static const struct regmap_config ltc2992_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+ .max_register = 0xE8,
+};
+
+static int ltc2992_parse_dt(struct ltc2992_state *st)
+{
+ struct fwnode_handle *fwnode;
+ struct fwnode_handle *child;
+ u32 addr;
+ u32 val;
+ int ret;
+
+ fwnode = dev_fwnode(&st->client->dev);
+
+ fwnode_for_each_available_child_node(fwnode, child) {
+ ret = fwnode_property_read_u32(child, "reg", &addr);
+ if (ret < 0)
+ return ret;
+
+ if (addr > 1)
+ return -EINVAL;
+
+ ret = fwnode_property_read_u32(child, "shunt-resistor-micro-ohms", &val);
+ if (!ret)
+ st->r_sense_uohm[addr] = val;
+ }
+
+ return 0;
+}
+
+static int ltc2992_i2c_probe(struct i2c_client *client, const struct i2c_device_id *id)
+{
+ struct device *hwmon_dev;
+ struct ltc2992_state *st;
+ int ret;
+
+ if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
+ return -ENODEV;
+
+ st = devm_kzalloc(&client->dev, sizeof(*st), GFP_KERNEL);
+ if (!st)
+ return -ENOMEM;
+
+ st->client = client;
+ st->regmap = devm_regmap_init_i2c(client, &ltc2992_regmap_config);
+ if (IS_ERR(st->regmap))
+ return PTR_ERR(st->regmap);
+
+ ret = ltc2992_parse_dt(st);
+ if (ret < 0)
+ return ret;
+
+ hwmon_dev = devm_hwmon_device_register_with_info(&client->dev, client->name, st,
+ &ltc2992_chip_info, NULL);
+
+ return PTR_ERR_OR_ZERO(hwmon_dev);
+}
+
+static const struct of_device_id ltc2992_of_match[] = {
+ { .compatible = "adi,ltc2992" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, ltc2992_of_match);
+
+static const struct i2c_device_id ltc2992_i2c_id[] = {
+ {"ltc2992", 0},
+ {}
+};
+MODULE_DEVICE_TABLE(i2c, ltc2992_i2c_id);
+
+static struct i2c_driver ltc2992_i2c_driver = {
+ .driver = {
+ .name = "ltc2992",
+ .of_match_table = ltc2992_of_match,
+ },
+ .probe = ltc2992_i2c_probe,
+ .id_table = ltc2992_i2c_id,
+};
+
+module_i2c_driver(ltc2992_i2c_driver);
+
+MODULE_AUTHOR("Alexandru Tachici <alexandru.tachici@xxxxxxxxxx>");
+MODULE_DESCRIPTION("Hwmon driver for Linear Technology 2992");
+MODULE_LICENSE("Dual BSD/GPL");
--
2.20.1