On Thu, Oct 12, 2023 at 01:29:36PM +0300, Antoniu Miclaus wrote: > Add support for LTC2991 Octal I2C Voltage, Current, and Temperature > Monitor. > > The LTC2991 is used to monitor system temperatures, voltages and > currents. Through the I2C serial interface, the eight monitors can > individually measure supply voltages and can be paired for > differential measurements of current sense resistors or temperature > sensing transistors. Additional measurements include internal > temperature and internal VCC. > > Signed-off-by: Antoniu Miclaus <antoniu.miclaus@xxxxxxxxxx> > --- > changes in v4: > - rework ltc2991_read_reg > - remove labels > - rework channel exposure according to datasheet part typical apllications > - avoid division by 0 by checking property value > Documentation/hwmon/index.rst | 1 + > Documentation/hwmon/ltc2991.rst | 43 ++++ > MAINTAINERS | 8 + > drivers/hwmon/Kconfig | 11 + > drivers/hwmon/Makefile | 1 + > drivers/hwmon/ltc2991.c | 437 ++++++++++++++++++++++++++++++++ > 6 files changed, 501 insertions(+) > create mode 100644 Documentation/hwmon/ltc2991.rst > create mode 100644 drivers/hwmon/ltc2991.c > > diff --git a/Documentation/hwmon/index.rst b/Documentation/hwmon/index.rst > index 88dadea85cfc..0ec96abe3f7d 100644 > --- a/Documentation/hwmon/index.rst > +++ b/Documentation/hwmon/index.rst > @@ -121,6 +121,7 @@ Hardware Monitoring Kernel Drivers > ltc2947 > ltc2978 > ltc2990 > + ltc2991 > ltc3815 > ltc4151 > ltc4215 > diff --git a/Documentation/hwmon/ltc2991.rst b/Documentation/hwmon/ltc2991.rst > new file mode 100644 > index 000000000000..9ab29dd85012 > --- /dev/null > +++ b/Documentation/hwmon/ltc2991.rst > @@ -0,0 +1,43 @@ > +.. SPDX-License-Identifier: GPL-2.0 > + > +Kernel driver ltc2991 > +===================== > + > +Supported chips: > + > + * Analog Devices LTC2991 > + > + Prefix: 'ltc2991' > + > + Addresses scanned: I2C 0x48 - 0x4f > + > + Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/2991ff.pdf > + > +Authors: > + > + - Antoniu Miclaus <antoniu.miclaus@xxxxxxxxxx> > + > + > +Description > +----------- > + > +This driver supports hardware monitoring for Analog Devices LTC2991 Octal I2C > +Voltage, Current and Temperature Monitor. > + > +The LTC2991 is used to monitor system temperatures, voltages and currents. > +Through the I2C serial interface, the eight monitors can individually measure > +supply voltages and can be paired for differential measurements of current sense > +resistors or temperature sensing transistors. Additional measurements include > +internal temperatureand internal VCC. > + > + > +sysfs-Interface > +------------- > + > +The following attributes are supported. Limits are read-only. > + > +=============== ================= > +inX_input: voltage input > +currX_input: current input > +tempX_input: temperature input > +=============== ================= > diff --git a/MAINTAINERS b/MAINTAINERS > index 6c4cce45a09d..edfa49c42848 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -12449,6 +12449,14 @@ F: drivers/hwmon/ltc2947-i2c.c > F: drivers/hwmon/ltc2947-spi.c > F: drivers/hwmon/ltc2947.h > > +LTC2991 HARDWARE MONITOR DRIVER > +M: Antoniu Miclaus <antoniu.miclaus@xxxxxxxxxx> > +L: linux-hwmon@xxxxxxxxxxxxxxx > +S: Supported > +W: https://ez.analog.com/linux-software-drivers > +F: Documentation/devicetree/bindings/hwmon/adi,ltc2991.yaml > +F: drivers/hwmon/ltc2991.c > + > LTC2983 IIO TEMPERATURE DRIVER > M: Nuno Sá <nuno.sa@xxxxxxxxxx> > L: linux-iio@xxxxxxxxxxxxxxx > diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig > index ec38c8892158..818a67328fcd 100644 > --- a/drivers/hwmon/Kconfig > +++ b/drivers/hwmon/Kconfig > @@ -932,6 +932,17 @@ config SENSORS_LTC2990 > This driver can also be built as a module. If so, the module will > be called ltc2990. > > +config SENSORS_LTC2991 > + tristate "Analog Devices LTC2991" > + depends on I2C > + help > + If you say yes here you get support for Analog Devices LTC2991 > + Octal I2C Voltage, Current, and Temperature Monitor. The LTC2991 > + supports a combination of voltage, current and temperature monitoring. > + > + This driver can also be built as a module. If so, the module will > + be called ltc2991. > + > config SENSORS_LTC2992 > tristate "Linear Technology LTC2992" > depends on I2C > diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile > index 4ac9452b5430..f324d057535a 100644 > --- a/drivers/hwmon/Makefile > +++ b/drivers/hwmon/Makefile > @@ -127,6 +127,7 @@ 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-$(CONFIG_SENSORS_LTC2991) += ltc2991.o > obj-$(CONFIG_SENSORS_LTC2992) += ltc2992.o > obj-$(CONFIG_SENSORS_LTC4151) += ltc4151.o > obj-$(CONFIG_SENSORS_LTC4215) += ltc4215.o > diff --git a/drivers/hwmon/ltc2991.c b/drivers/hwmon/ltc2991.c > new file mode 100644 > index 000000000000..4f3d73bc494a > --- /dev/null > +++ b/drivers/hwmon/ltc2991.c > @@ -0,0 +1,437 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Copyright (C) 2023 Analog Devices, Inc. > + * Author: Antoniu Miclaus <antoniu.miclaus@xxxxxxxxxx> > + */ > + > +#include <linux/bitops.h> > +#include <linux/err.h> > +#include <linux/hwmon.h> > +#include <linux/hwmon-sysfs.h> I don't see why this include file would be needed. > +#include <linux/i2c.h> > +#include <linux/kernel.h> > +#include <linux/module.h> > +#include <linux/property.h> > +#include <linux/regmap.h> > +#include <linux/regulator/consumer.h> > + > +#include <asm/unaligned.h> There are no unaligned accesses, so it appears that this include is not needed either. > + > +#define LTC2991_STATUS_LOW 0x00 > +#define LTC2991_CH_EN_TRIGGER 0x01 > +#define LTC2991_V1_V4_CTRL 0x06 > +#define LTC2991_V5_V8_CTRL 0x07 > +#define LTC2991_PWM_TH_LSB_T_INT 0x08 > +#define LTC2991_PWM_TH_MSB 0x09 > +#define LTC2991_CHANNEL_V_MSB(x) (0x0A + ((x) * 2)) > +#define LTC2991_CHANNEL_T_MSB(x) (0x0A + ((x) * 4)) > +#define LTC2991_CHANNEL_C_MSB(x) (0x0C + ((x) * 4)) > +#define LTC2991_T_INT_MSB 0x1A > +#define LTC2991_VCC_MSB 0x1C > + > +#define LTC2991_V7_V8_EN BIT(7) > +#define LTC2991_V5_V6_EN BIT(6) > +#define LTC2991_V3_V4_EN BIT(5) > +#define LTC2991_V1_V2_EN BIT(4) > +#define LTC2991_T_INT_VCC_EN BIT(3) > + > +#define LTC2991_V3_V4_FILT_EN BIT(7) > +#define LTC2991_V3_V4_TEMP_EN BIT(5) > +#define LTC2991_V3_V4_DIFF_EN BIT(4) > +#define LTC2991_V1_V2_FILT_EN BIT(3) > +#define LTC2991_V1_V2_TEMP_EN BIT(1) > +#define LTC2991_V1_V2_DIFF_EN BIT(0) > + > +#define LTC2991_V7_V8_FILT_EN BIT(7) > +#define LTC2991_V7_V8_TEMP_EN BIT(5) > +#define LTC2991_V7_V8_DIFF_EN BIT(4) > +#define LTC2991_V5_V6_FILT_EN BIT(7) > +#define LTC2991_V5_V6_TEMP_EN BIT(5) > +#define LTC2991_V5_V6_DIFF_EN BIT(4) > + > +#define LTC2991_REPEAT_ACQ_EN BIT(4) > +#define LTC2991_T_INT_FILT_EN BIT(3) > + > +#define LTC2991_MAX_CHANNEL 4 > +#define LTC2991_T_INT_CH_NR 4 > +#define LTC2991_VCC_CH_NR 0 > + > +struct ltc2991_state { > + struct i2c_client *client; This is only used in the init function, and each time it is used it is derefernced as &st->client->dev. Just pass dev as parameter and be done with it. > + struct regmap *regmap; > + u32 r_sense_uohm[LTC2991_MAX_CHANNEL]; > + bool temp_en[LTC2991_MAX_CHANNEL]; > +}; > + > +static int ltc2991_read_reg(struct ltc2991_state *st, u8 addr, u8 reg_len, > + int *val) > +{ > + __be16 regvals; > + int ret; > + > + if (reg_len < 2) > + return regmap_read(st->regmap, addr, val); > + > + ret = regmap_bulk_read(st->regmap, addr, ®vals, reg_len); > + if (ret) > + return ret; > + > + *val = be16_to_cpu(regvals); > + > + return 0; > +} > + > +static int ltc2991_get_voltage(struct ltc2991_state *st, u32 reg, long *val) > +{ > + int reg_val, ret, offset = 0; > + > + ret = ltc2991_read_reg(st, reg, 2, ®_val); > + if (ret) > + return ret; > + > + if (reg == LTC2991_VCC_MSB) > + /* Vcc 2.5V offset */ > + offset = 2500; > + > + /* Vx, 305.18uV/LSB */ > + *val = DIV_ROUND_CLOSEST(sign_extend32(reg_val, 14) * 30518, > + 1000 * 100) + offset; > + > + return 0; > +} > + > +static int ltc2991_read_in(struct device *dev, u32 attr, int channel, long *val) > +{ > + struct ltc2991_state *st = dev_get_drvdata(dev); > + u32 reg; > + > + switch (attr) { > + case hwmon_in_input: > + if (channel == LTC2991_VCC_CH_NR) > + reg = LTC2991_VCC_MSB; > + else > + reg = LTC2991_CHANNEL_V_MSB(channel - 1); > + > + return ltc2991_get_voltage(st, reg, val); > + default: > + return -EOPNOTSUPP; > + } > +} > + > +static int ltc2991_get_curr(struct ltc2991_state *st, u32 reg, int channel, > + long *val) > +{ > + int reg_val, ret; > + > + ret = ltc2991_read_reg(st, reg, 2, ®_val); > + if (ret) > + return ret; > + > + /* Vx-Vy, 19.075uV/LSB */ > + *val = DIV_ROUND_CLOSEST(sign_extend32(reg_val, 14) * 19075, 1000) > + / (st->r_sense_uohm[channel] / 1000); If st->r_sense_uohm[channel] < 1000, the divide operation will result in a division by zero error. Also, there is a loss of accuracy because the sense resistor is rounded to mOhm before being used. > + > + return 0; > +} > + > +static int ltc2991_read_curr(struct device *dev, u32 attr, int channel, > + long *val) > +{ > + struct ltc2991_state *st = dev_get_drvdata(dev); > + u32 reg; > + > + switch (attr) { > + case hwmon_curr_input: > + reg = LTC2991_CHANNEL_C_MSB(channel); > + return ltc2991_get_curr(st, reg, channel, val); > + default: > + return -EOPNOTSUPP; > + } > +} > + > +static int ltc2991_get_temp(struct ltc2991_state *st, u32 reg, int channel, > + long *val) > +{ > + int reg_val, ret; > + > + ret = ltc2991_read_reg(st, reg, 2, ®_val); > + if (ret) > + return ret; > + > + /* Temp LSB = 0.0625 Degrees */ > + *val = DIV_ROUND_CLOSEST(sign_extend32(reg_val, 12) * 1000, 16); > + > + return 0; > +} > + > +static int ltc2991_read_temp(struct device *dev, u32 attr, int channel, > + long *val) > +{ > + struct ltc2991_state *st = dev_get_drvdata(dev); > + u32 reg; > + > + switch (attr) { > + case hwmon_temp_input: > + if (channel == LTC2991_T_INT_CH_NR) > + reg = LTC2991_T_INT_MSB; > + else > + reg = LTC2991_CHANNEL_T_MSB(channel); > + > + return ltc2991_get_temp(st, reg, channel, val); > + default: > + return -EOPNOTSUPP; > + } > +} > + > +static int ltc2991_read(struct device *dev, enum hwmon_sensor_types type, > + u32 attr, int channel, long *val) > +{ > + switch (type) { > + case hwmon_in: > + return ltc2991_read_in(dev, attr, channel, val); > + case hwmon_curr: > + return ltc2991_read_curr(dev, attr, channel, val); > + case hwmon_temp: > + return ltc2991_read_temp(dev, attr, channel, val); > + default: > + return -EOPNOTSUPP; > + } > +} > + > +static umode_t ltc2991_is_visible(const void *data, > + enum hwmon_sensor_types type, u32 attr, > + int channel) > +{ > + const struct ltc2991_state *st = data; > + > + switch (type) { > + case hwmon_in: > + switch (attr) { > + case hwmon_in_input: > + if (channel == LTC2991_VCC_CH_NR) > + return 0444; > + if (st->temp_en[(channel - 1) / 2]) > + break; > + if (channel % 2) > + return 0444; > + if (!st->r_sense_uohm[(channel - 1) / 2]) > + return 0444; > + } > + break; > + case hwmon_curr: > + switch (attr) { > + case hwmon_curr_input: > + if (st->r_sense_uohm[channel]) > + return 0444; > + break; > + } > + break; > + case hwmon_temp: > + switch (attr) { > + case hwmon_temp_input: > + if (st->temp_en[channel] || > + channel == LTC2991_T_INT_CH_NR) > + return 0444; > + break; > + } > + break; > + default: > + break; > + } > + > + return 0; > +} > + > +static const struct hwmon_ops ltc2991_hwmon_ops = { > + .is_visible = ltc2991_is_visible, > + .read = ltc2991_read, > +}; > + > +static const struct hwmon_channel_info *ltc2991_info[] = { > + HWMON_CHANNEL_INFO(temp, > + HWMON_T_INPUT, > + HWMON_T_INPUT, > + HWMON_T_INPUT, > + HWMON_T_INPUT, > + HWMON_T_INPUT > + ), > + HWMON_CHANNEL_INFO(curr, > + HWMON_C_INPUT, > + HWMON_C_INPUT, > + HWMON_C_INPUT, > + HWMON_C_INPUT > + ), > + HWMON_CHANNEL_INFO(in, > + HWMON_I_INPUT, > + HWMON_I_INPUT, > + HWMON_I_INPUT, > + HWMON_I_INPUT, > + HWMON_I_INPUT, > + HWMON_I_INPUT, > + HWMON_I_INPUT, > + HWMON_I_INPUT, > + HWMON_I_INPUT > + ), > + NULL > +}; > + > +static const struct hwmon_chip_info ltc2991_chip_info = { > + .ops = <c2991_hwmon_ops, > + .info = ltc2991_info, > +}; > + > +static const struct regmap_config ltc2991_regmap_config = { > + .reg_bits = 8, > + .val_bits = 8, > + .max_register = 0x1D, > +}; > + > +static int ltc2991_init(struct ltc2991_state *st) > +{ > + struct fwnode_handle *child; > + int ret; > + u32 val, addr; > + u8 v5_v8_reg_data = 0, v1_v4_reg_data = 0; > + > + ret = devm_regulator_get_enable(&st->client->dev, "vcc"); > + if (ret) > + return dev_err_probe(&st->client->dev, ret, > + "failed to enable regulator\n"); > + > + device_for_each_child_node(&st->client->dev, child) { > + ret = fwnode_property_read_u32(child, "reg", &addr); > + if (ret < 0) { > + fwnode_handle_put(child); > + return ret; > + } > + > + if (addr > 3) { > + fwnode_handle_put(child); > + return -EINVAL; > + } > + > + ret = fwnode_property_read_u32(child, "shunt-resistor-micro-ohms", &val); > + if (!ret) { > + if (!val) > + return dev_err_probe(&st->client->dev, -EINVAL, > + "shunt resistor value cannot be zero\n"); > + > + st->r_sense_uohm[addr] = val; > + > + switch (addr) { > + case 0: > + v1_v4_reg_data |= LTC2991_V1_V2_DIFF_EN; > + break; > + case 1: > + v1_v4_reg_data |= LTC2991_V3_V4_DIFF_EN; > + break; > + case 2: > + v5_v8_reg_data |= LTC2991_V5_V6_DIFF_EN; > + break; > + case 3: > + v5_v8_reg_data |= LTC2991_V7_V8_DIFF_EN; > + break; > + default: > + break; > + } > + } > + > + ret = fwnode_property_read_bool(child, "adi,temperature-enable"); > + if (ret) { > + st->temp_en[addr] = ret; > + > + switch (addr) { > + case 0: > + v1_v4_reg_data |= LTC2991_V1_V2_TEMP_EN; > + break; > + case 1: > + v1_v4_reg_data |= LTC2991_V3_V4_TEMP_EN; > + break; > + case 2: > + v5_v8_reg_data |= LTC2991_V5_V6_TEMP_EN; > + break; > + case 3: > + v5_v8_reg_data |= LTC2991_V7_V8_TEMP_EN; > + break; > + default: > + break; > + } > + } > + } > + > + ret = regmap_write(st->regmap, LTC2991_V5_V8_CTRL, v5_v8_reg_data); > + if (ret) > + return dev_err_probe(&st->client->dev, ret, > + "Error: Failed to set V5-V8 CTRL reg.\n"); > + > + ret = regmap_write(st->regmap, LTC2991_V1_V4_CTRL, v1_v4_reg_data); > + if (ret) > + return dev_err_probe(&st->client->dev, ret, > + "Error: Failed to set V1-V4 CTRL reg.\n"); > + > + ret = regmap_write(st->regmap, LTC2991_PWM_TH_LSB_T_INT, > + LTC2991_REPEAT_ACQ_EN); > + if (ret) > + return dev_err_probe(&st->client->dev, ret, > + "Error: Failed to set contiuous mode.\n"); > + > + /* Enable all channels and trigger conversions */ > + return regmap_write(st->regmap, LTC2991_CH_EN_TRIGGER, > + LTC2991_V7_V8_EN | LTC2991_V5_V6_EN | > + LTC2991_V3_V4_EN | LTC2991_V1_V2_EN | > + LTC2991_T_INT_VCC_EN); > +} > + > +static int ltc2991_i2c_probe(struct i2c_client *client) > +{ > + int ret; > + struct device *hwmon_dev; > + struct ltc2991_state *st; > + > + st = devm_kzalloc(&client->dev, sizeof(*st), GFP_KERNEL); > + if (!st) > + return -ENOMEM; > + > + st->client = client; > + st->regmap = devm_regmap_init_i2c(client, <c2991_regmap_config); > + if (IS_ERR(st->regmap)) > + return PTR_ERR(st->regmap); > + > + ret = ltc2991_init(st); > + if (ret) > + return ret; > + > + hwmon_dev = devm_hwmon_device_register_with_info(&client->dev, > + client->name, st, > + <c2991_chip_info, > + NULL); > + > + return PTR_ERR_OR_ZERO(hwmon_dev); > +} > + > +static const struct of_device_id ltc2991_of_match[] = { > + { .compatible = "adi,ltc2991" }, > + { } > +}; > +MODULE_DEVICE_TABLE(of, ltc2991_of_match); > + > +static const struct i2c_device_id ltc2991_i2c_id[] = { > + { "ltc2991", 0 }, > + {} > +}; > +MODULE_DEVICE_TABLE(i2c, ltc2991_i2c_id); > + > +static struct i2c_driver ltc2991_i2c_driver = { > + .driver = { > + .name = "ltc2991", > + .of_match_table = ltc2991_of_match, > + }, > + .probe = ltc2991_i2c_probe, > + .id_table = ltc2991_i2c_id, > +}; > + > +module_i2c_driver(ltc2991_i2c_driver); > + > +MODULE_AUTHOR("Antoniu Miclaus <antoniu.miclaus@xxxxxxxxxx>"); > +MODULE_DESCRIPTION("Analog Devices LTC2991 HWMON Driver"); > +MODULE_LICENSE("GPL");
