The LTC2990 driver so far only supported "current" monitoring. This expands the driver to support all 8 modes of operation as defined in the mode bits in the datasheet, thus the device can now be used to monitor up to 4 voltages, 2 currents, or 2 temperature sensors, and some combinations thereof.
The device mode is configured by using the "mode" value as device name, e.g. specifying compatible="lltc,ltc2990-6" in the devicetree will set it to dual-current monitoring mode (6). For backward compatibility, the default is mode 6. Signed-off-by: Mike Looijmans <[email protected]> --- drivers/hwmon/Kconfig | 8 +-- drivers/hwmon/ltc2990.c | 172 ++++++++++++++++++++++++++++++++++++++++-------- 2 files changed, 148 insertions(+), 32 deletions(-) diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig index 5c2d13a..242e22f 100644 --- a/drivers/hwmon/Kconfig +++ b/drivers/hwmon/Kconfig @@ -686,15 +686,13 @@ config SENSORS_LTC2945 be called ltc2945. config SENSORS_LTC2990 - tristate "Linear Technology LTC2990 (current monitoring mode only)" + tristate "Linear Technology LTC2990" depends on I2C help If you say yes here you get support for Linear Technology LTC2990 I2C System Monitor. The LTC2990 supports a combination of voltage, - current and temperature monitoring, but in addition to the Vcc supply - voltage and chip temperature, this driver currently only supports - reading two currents by measuring two differential voltages across - series resistors. + current and temperature monitoring, in addition to the Vcc supply + voltage and chip temperature. This driver can also be built as a module. If so, the module will be called ltc2990. diff --git a/drivers/hwmon/ltc2990.c b/drivers/hwmon/ltc2990.c index 8f8fe05..9c621a1 100644 --- a/drivers/hwmon/ltc2990.c +++ b/drivers/hwmon/ltc2990.c @@ -6,9 +6,10 @@ * * License: GPLv2 * - * This driver assumes the chip is wired as a dual current monitor, and - * reports the voltage drop across two series resistors. It also reports - * the chip's internal temperature and Vcc power supply voltage. + * To configure the driver, pass its desired "mode" (lower 3 bits of control + * register) as its device name. Depending on this mode, the chip will report + * temperature, current and/or voltage measuments. It always reports the chip's + * internal temperature and Vcc power supply voltage. */ #include <linux/err.h> @@ -27,12 +28,18 @@ #define LTC2990_V3_MSB 0x0A #define LTC2990_V4_MSB 0x0C #define LTC2990_VCC_MSB 0x0E +#define LTC2990_REGISTER_MASK 0x0F #define LTC2990_CONTROL_KELVIN BIT(7) #define LTC2990_CONTROL_SINGLE BIT(6) #define LTC2990_CONTROL_MEASURE_ALL (0x3 << 3) -#define LTC2990_CONTROL_MODE_CURRENT 0x06 -#define LTC2990_CONTROL_MODE_VOLTAGE 0x07 +#define LTC2990_CONTROL_MODE_DEFAULT 0x06 + +#define LTC2990_CONVERSION_CURRENT 0x00 +#define LTC2990_CONVERSION_TEMPERATURE 0x40 +#define LTC2990_CONVERSION_VOLTAGE 0x80 +#define LTC2990_CONVERSION_VOLTAGE25 0xC0 +#define LTC2990_CONVERSION_MASK 0xC0 /* convert raw register value to sign-extended integer in 16-bit range */ static int ltc2990_voltage_to_int(int raw) @@ -44,26 +51,30 @@ static int ltc2990_voltage_to_int(int raw) } /* Return the converted value from the given register in uV or mC */ -static int ltc2990_get_value(struct i2c_client *i2c, u8 reg, int *result) +static int ltc2990_get_value(struct i2c_client *i2c, u8 conv_reg, int *result) { int val; - val = i2c_smbus_read_word_swapped(i2c, reg); + val = i2c_smbus_read_word_swapped(i2c, conv_reg & LTC2990_REGISTER_MASK); if (unlikely(val < 0)) return val; - switch (reg) { - case LTC2990_TINT_MSB: - /* internal temp, 0.0625 degrees/LSB, 13-bit */ + switch (conv_reg & LTC2990_CONVERSION_MASK) { + case LTC2990_CONVERSION_CURRENT: + /* Current as differential Vx-Vy, 19.42uV/LSB. */ + *result = ltc2990_voltage_to_int(val) * 1942 / (4 * 100); + break; + case LTC2990_CONVERSION_TEMPERATURE: + /* Temperature, 0.0625 degrees/LSB, 13-bit */ val = (val & 0x1FFF) << 3; *result = (val * 1000) >> 7; break; - case LTC2990_V1_MSB: - case LTC2990_V3_MSB: - /* Vx-Vy, 19.42uV/LSB. Depends on mode. */ - *result = ltc2990_voltage_to_int(val) * 1942 / (4 * 100); + case LTC2990_CONVERSION_VOLTAGE: + /* Voltage, 305.18μV/LSB */ + *result = (ltc2990_voltage_to_int(val) * 30518 / + (4 * 100 * 1000)); break; - case LTC2990_VCC_MSB: + case LTC2990_CONVERSION_VOLTAGE25: /* Vcc, 305.18μV/LSB, 2.5V offset */ *result = (ltc2990_voltage_to_int(val) * 30518 / (4 * 100 * 1000)) + 2500; @@ -89,38 +100,129 @@ static ssize_t ltc2990_show_value(struct device *dev, return snprintf(buf, PAGE_SIZE, "%d\n", value); } +/* Internal temperature and Vcc voltage are always present */ static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, ltc2990_show_value, NULL, - LTC2990_TINT_MSB); + LTC2990_CONVERSION_TEMPERATURE | LTC2990_TINT_MSB); +static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, ltc2990_show_value, NULL, + LTC2990_CONVERSION_VOLTAGE25 | LTC2990_VCC_MSB); +/* Current measurement requires 2 inputs per channel */ static SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO, ltc2990_show_value, NULL, - LTC2990_V1_MSB); + LTC2990_CONVERSION_CURRENT | LTC2990_V1_MSB); static SENSOR_DEVICE_ATTR(curr2_input, S_IRUGO, ltc2990_show_value, NULL, - LTC2990_V3_MSB); -static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, ltc2990_show_value, NULL, - LTC2990_VCC_MSB); + LTC2990_CONVERSION_CURRENT | LTC2990_V3_MSB); +/* Voltage measurement requires 1 input per channel */ +static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, ltc2990_show_value, NULL, + LTC2990_CONVERSION_VOLTAGE | LTC2990_V1_MSB); +static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, ltc2990_show_value, NULL, + LTC2990_CONVERSION_VOLTAGE | LTC2990_V2_MSB); +static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, ltc2990_show_value, NULL, + LTC2990_CONVERSION_VOLTAGE | LTC2990_V3_MSB); +static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, ltc2990_show_value, NULL, + LTC2990_CONVERSION_VOLTAGE | LTC2990_V4_MSB); +/* Temperature measurement requires 2 inputs per channel */ +static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, ltc2990_show_value, NULL, + LTC2990_CONVERSION_TEMPERATURE | LTC2990_V1_MSB); +static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, ltc2990_show_value, NULL, + LTC2990_CONVERSION_TEMPERATURE | LTC2990_V3_MSB); -static struct attribute *ltc2990_attrs[] = { + +/* Common attributes regardless of mode */ +static struct attribute *ltc2990_common_attrs[] = { &sensor_dev_attr_temp1_input.dev_attr.attr, + &sensor_dev_attr_in0_input.dev_attr.attr, + NULL, +}; +static const struct attribute_group ltc2990_common_group = { + .attrs = ltc2990_common_attrs, +}; + +/* Attribute to mode mapping, as per the CONTROL register bits [2:0] */ + +/* 000 = V1 V2 TR2 */ +static struct attribute *ltc2990_000_attrs[] = { + &sensor_dev_attr_in1_input.dev_attr.attr, + &sensor_dev_attr_in2_input.dev_attr.attr, + &sensor_dev_attr_temp3_input.dev_attr.attr, + NULL, +}; +/* 001 = V1-V2 TR2 */ +static struct attribute *ltc2990_001_attrs[] = { + &sensor_dev_attr_curr1_input.dev_attr.attr, + &sensor_dev_attr_temp3_input.dev_attr.attr, + NULL, +}; +/* 010 = V1-V2 V3 V4 */ +static struct attribute *ltc2990_010_attrs[] = { &sensor_dev_attr_curr1_input.dev_attr.attr, + &sensor_dev_attr_in3_input.dev_attr.attr, + &sensor_dev_attr_in4_input.dev_attr.attr, + NULL, +}; +/* 011 = TR1 V3 V4 */ +static struct attribute *ltc2990_011_attrs[] = { + &sensor_dev_attr_temp2_input.dev_attr.attr, + &sensor_dev_attr_in3_input.dev_attr.attr, + &sensor_dev_attr_in4_input.dev_attr.attr, + NULL, +}; +/* 100 = TR1 V3-V4 */ +static struct attribute *ltc2990_100_attrs[] = { + &sensor_dev_attr_temp2_input.dev_attr.attr, &sensor_dev_attr_curr2_input.dev_attr.attr, - &sensor_dev_attr_in0_input.dev_attr.attr, NULL, }; -ATTRIBUTE_GROUPS(ltc2990); +/* 101 = TR1 TR2 */ +static struct attribute *ltc2990_101_attrs[] = { + &sensor_dev_attr_temp2_input.dev_attr.attr, + &sensor_dev_attr_temp3_input.dev_attr.attr, + NULL, +}; +/* 110 = V1-V2 V3-V4 */ +static struct attribute *ltc2990_110_attrs[] = { + &sensor_dev_attr_curr1_input.dev_attr.attr, + &sensor_dev_attr_curr2_input.dev_attr.attr, + NULL, +}; +/* 111 = V1 V2 V3 V4 */ +static struct attribute *ltc2990_111_attrs[] = { + &sensor_dev_attr_in1_input.dev_attr.attr, + &sensor_dev_attr_in2_input.dev_attr.attr, + &sensor_dev_attr_in3_input.dev_attr.attr, + &sensor_dev_attr_in4_input.dev_attr.attr, + NULL, +}; +/* Decoder array for mode index */ +static struct attribute **ltc2990_attr_list[] = { + ltc2990_000_attrs, + ltc2990_001_attrs, + ltc2990_010_attrs, + ltc2990_011_attrs, + ltc2990_100_attrs, + ltc2990_101_attrs, + ltc2990_110_attrs, + ltc2990_111_attrs, +}; + +struct ltc2990_driver_data { + struct attribute_group ltc2990_extra_group; + const struct attribute_group *ltc2990_groups[3]; +}; static int ltc2990_i2c_probe(struct i2c_client *i2c, const struct i2c_device_id *id) { int ret; struct device *hwmon_dev; + struct ltc2990_driver_data *data; if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA)) return -ENODEV; - /* Setup continuous mode, current monitor */ + /* Setup continuous monitoring mode */ ret = i2c_smbus_write_byte_data(i2c, LTC2990_CONTROL, LTC2990_CONTROL_MEASURE_ALL | - LTC2990_CONTROL_MODE_CURRENT); + id->driver_data); if (ret < 0) { dev_err(&i2c->dev, "Error: Failed to set control mode.\n"); return ret; @@ -132,16 +234,32 @@ static int ltc2990_i2c_probe(struct i2c_client *i2c, return ret; } + /* Define attributes based on chip mode */ + data = devm_kzalloc(&i2c->dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + data->ltc2990_extra_group.attrs = ltc2990_attr_list[id->driver_data]; + data->ltc2990_groups[0] = <c2990_common_group; + data->ltc2990_groups[1] = &data->ltc2990_extra_group; + hwmon_dev = devm_hwmon_device_register_with_groups(&i2c->dev, i2c->name, i2c, - ltc2990_groups); + data->ltc2990_groups); return PTR_ERR_OR_ZERO(hwmon_dev); } static const struct i2c_device_id ltc2990_i2c_id[] = { - { "ltc2990", 0 }, + { "ltc2990", LTC2990_CONTROL_MODE_DEFAULT}, + { "ltc29900", 0}, + { "ltc29901", 1}, + { "ltc29902", 2}, + { "ltc29903", 3}, + { "ltc29904", 4}, + { "ltc29905", 5}, + { "ltc29906", 6}, + { "ltc29907", 7}, {} }; MODULE_DEVICE_TABLE(i2c, ltc2990_i2c_id); -- 1.9.1
