diff options
-rw-r--r-- | Documentation/hwmon/ltc2990 | 24 | ||||
-rw-r--r-- | drivers/hwmon/Kconfig | 7 | ||||
-rw-r--r-- | drivers/hwmon/ltc2990.c | 196 |
3 files changed, 185 insertions, 42 deletions
diff --git a/Documentation/hwmon/ltc2990 b/Documentation/hwmon/ltc2990 index c25211e90bdc..3ed68f676c0f 100644 --- a/Documentation/hwmon/ltc2990 +++ b/Documentation/hwmon/ltc2990 @@ -8,6 +8,7 @@ Supported chips: Datasheet: http://www.linear.com/product/ltc2990 Author: Mike Looijmans <mike.looijmans@topic.nl> + Tom Levens <tom.levens@cern.ch> Description @@ -16,10 +17,8 @@ Description LTC2990 is a Quad I2C Voltage, Current and Temperature Monitor. The chip's inputs can measure 4 voltages, or two inputs together (1+2 and 3+4) can be combined to measure a differential voltage, which is typically used to -measure current through a series resistor, or a temperature. - -This driver currently uses the 2x differential mode only. In order to support -other modes, the driver will need to be expanded. +measure current through a series resistor, or a temperature with an external +diode. Usage Notes @@ -32,12 +31,19 @@ devices explicitly. Sysfs attributes ---------------- +in0_input Voltage at Vcc pin in millivolt (range 2.5V to 5V) +temp1_input Internal chip temperature in millidegrees Celcius + +A subset of the following attributes are visible, depending on the measurement +mode of the chip. + +in[1-4]_input Voltage at V[1-4] pin in millivolt +temp2_input External temperature sensor TR1 in millidegrees Celcius +temp3_input External temperature sensor TR2 in millidegrees Celcius +curr1_input Current in mA across V1-V2 assuming a 1mOhm sense resistor +curr2_input Current in mA across V3-V4 assuming a 1mOhm sense resistor + The "curr*_input" measurements actually report the voltage drop across the input pins in microvolts. This is equivalent to the current through a 1mOhm sense resistor. Divide the reported value by the actual sense resistor value in mOhm to get the actual value. - -in0_input Voltage at Vcc pin in millivolt (range 2.5V to 5V) -temp1_input Internal chip temperature in millidegrees Celcius -curr1_input Current in mA across v1-v2 assuming a 1mOhm sense resistor. -curr2_input Current in mA across v3-v4 assuming a 1mOhm sense resistor. diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig index 6ec307c93ece..f10840ad465c 100644 --- a/drivers/hwmon/Kconfig +++ b/drivers/hwmon/Kconfig @@ -717,15 +717,12 @@ 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. 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 e320d212ac27..2aefdc58b242 100644 --- a/drivers/hwmon/ltc2990.c +++ b/drivers/hwmon/ltc2990.c @@ -5,10 +5,6 @@ * Author: Mike Looijmans <mike.looijmans@topic.nl> * * 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. */ #include <linux/bitops.h> @@ -18,6 +14,7 @@ #include <linux/i2c.h> #include <linux/kernel.h> #include <linux/module.h> +#include <linux/of.h> #define LTC2990_STATUS 0x00 #define LTC2990_CONTROL 0x01 @@ -29,35 +26,109 @@ #define LTC2990_V4_MSB 0x0C #define LTC2990_VCC_MSB 0x0E -#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_IN0 BIT(0) +#define LTC2990_IN1 BIT(1) +#define LTC2990_IN2 BIT(2) +#define LTC2990_IN3 BIT(3) +#define LTC2990_IN4 BIT(4) +#define LTC2990_CURR1 BIT(5) +#define LTC2990_CURR2 BIT(6) +#define LTC2990_TEMP1 BIT(7) +#define LTC2990_TEMP2 BIT(8) +#define LTC2990_TEMP3 BIT(9) +#define LTC2990_NONE 0 +#define LTC2990_ALL GENMASK(9, 0) + +#define LTC2990_MODE0_SHIFT 0 +#define LTC2990_MODE0_MASK GENMASK(2, 0) +#define LTC2990_MODE1_SHIFT 3 +#define LTC2990_MODE1_MASK GENMASK(1, 0) + +/* Enabled measurements for mode bits 2..0 */ +static const int ltc2990_attrs_ena_0[] = { + LTC2990_IN1 | LTC2990_IN2 | LTC2990_TEMP3, + LTC2990_CURR1 | LTC2990_TEMP3, + LTC2990_CURR1 | LTC2990_IN3 | LTC2990_IN4, + LTC2990_TEMP2 | LTC2990_IN3 | LTC2990_IN4, + LTC2990_TEMP2 | LTC2990_CURR2, + LTC2990_TEMP2 | LTC2990_TEMP3, + LTC2990_CURR1 | LTC2990_CURR2, + LTC2990_IN1 | LTC2990_IN2 | LTC2990_IN3 | LTC2990_IN4 +}; + +/* Enabled measurements for mode bits 4..3 */ +static const int ltc2990_attrs_ena_1[] = { + LTC2990_NONE, + LTC2990_TEMP2 | LTC2990_IN1 | LTC2990_CURR1, + LTC2990_TEMP3 | LTC2990_IN3 | LTC2990_CURR2, + LTC2990_ALL +}; + +struct ltc2990_data { + struct i2c_client *i2c; + u32 mode[2]; +}; /* 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, int index, int *result) { int val; + u8 reg; + + switch (index) { + case LTC2990_IN0: + reg = LTC2990_VCC_MSB; + break; + case LTC2990_IN1: + case LTC2990_CURR1: + case LTC2990_TEMP2: + reg = LTC2990_V1_MSB; + break; + case LTC2990_IN2: + reg = LTC2990_V2_MSB; + break; + case LTC2990_IN3: + case LTC2990_CURR2: + case LTC2990_TEMP3: + reg = LTC2990_V3_MSB; + break; + case LTC2990_IN4: + reg = LTC2990_V4_MSB; + break; + case LTC2990_TEMP1: + reg = LTC2990_TINT_MSB; + break; + default: + return -EINVAL; + } val = i2c_smbus_read_word_swapped(i2c, reg); if (unlikely(val < 0)) return val; - switch (reg) { - case LTC2990_TINT_MSB: - /* internal temp, 0.0625 degrees/LSB, 13-bit */ + switch (index) { + case LTC2990_TEMP1: + case LTC2990_TEMP2: + case LTC2990_TEMP3: + /* temp, 0.0625 degrees/LSB */ *result = sign_extend32(val, 12) * 1000 / 16; break; - case LTC2990_V1_MSB: - case LTC2990_V3_MSB: - /* Vx-Vy, 19.42uV/LSB. Depends on mode. */ + case LTC2990_CURR1: + case LTC2990_CURR2: + /* Vx-Vy, 19.42uV/LSB */ *result = sign_extend32(val, 14) * 1942 / 100; break; - case LTC2990_VCC_MSB: - /* Vcc, 305.18μV/LSB, 2.5V offset */ + case LTC2990_IN0: + /* Vcc, 305.18uV/LSB, 2.5V offset */ *result = sign_extend32(val, 14) * 30518 / (100 * 1000) + 2500; break; + case LTC2990_IN1: + case LTC2990_IN2: + case LTC2990_IN3: + case LTC2990_IN4: + /* Vx, 305.18uV/LSB */ + *result = sign_extend32(val, 14) * 30518 / (100 * 1000); + break; default: return -EINVAL; /* won't happen, keep compiler happy */ } @@ -69,48 +140,117 @@ static ssize_t ltc2990_show_value(struct device *dev, struct device_attribute *da, char *buf) { struct sensor_device_attribute *attr = to_sensor_dev_attr(da); + struct ltc2990_data *data = dev_get_drvdata(dev); int value; int ret; - ret = ltc2990_get_value(dev_get_drvdata(dev), attr->index, &value); + ret = ltc2990_get_value(data->i2c, attr->index, &value); if (unlikely(ret < 0)) return ret; return snprintf(buf, PAGE_SIZE, "%d\n", value); } +static umode_t ltc2990_attrs_visible(struct kobject *kobj, + struct attribute *a, int n) +{ + struct device *dev = container_of(kobj, struct device, kobj); + struct ltc2990_data *data = dev_get_drvdata(dev); + struct device_attribute *da = + container_of(a, struct device_attribute, attr); + struct sensor_device_attribute *attr = to_sensor_dev_attr(da); + + int attrs_mask = LTC2990_IN0 | LTC2990_TEMP1 | + (ltc2990_attrs_ena_0[data->mode[0]] & + ltc2990_attrs_ena_1[data->mode[1]]); + + if (attr->index & attrs_mask) + return a->mode; + + return 0; +} + static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, ltc2990_show_value, NULL, - LTC2990_TINT_MSB); + LTC2990_TEMP1); +static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, ltc2990_show_value, NULL, + LTC2990_TEMP2); +static SENSOR_DEVICE_ATTR(temp3_input, S_IRUGO, ltc2990_show_value, NULL, + LTC2990_TEMP3); static SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO, ltc2990_show_value, NULL, - LTC2990_V1_MSB); + LTC2990_CURR1); static SENSOR_DEVICE_ATTR(curr2_input, S_IRUGO, ltc2990_show_value, NULL, - LTC2990_V3_MSB); + LTC2990_CURR2); static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, ltc2990_show_value, NULL, - LTC2990_VCC_MSB); + LTC2990_IN0); +static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, ltc2990_show_value, NULL, + LTC2990_IN1); +static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, ltc2990_show_value, NULL, + LTC2990_IN2); +static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, ltc2990_show_value, NULL, + LTC2990_IN3); +static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, ltc2990_show_value, NULL, + LTC2990_IN4); static struct attribute *ltc2990_attrs[] = { &sensor_dev_attr_temp1_input.dev_attr.attr, + &sensor_dev_attr_temp2_input.dev_attr.attr, + &sensor_dev_attr_temp3_input.dev_attr.attr, &sensor_dev_attr_curr1_input.dev_attr.attr, &sensor_dev_attr_curr2_input.dev_attr.attr, &sensor_dev_attr_in0_input.dev_attr.attr, + &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, }; -ATTRIBUTE_GROUPS(ltc2990); + +static const struct attribute_group ltc2990_group = { + .attrs = ltc2990_attrs, + .is_visible = ltc2990_attrs_visible, +}; +__ATTRIBUTE_GROUPS(ltc2990); static int ltc2990_i2c_probe(struct i2c_client *i2c, const struct i2c_device_id *id) { int ret; struct device *hwmon_dev; + struct ltc2990_data *data; + struct device_node *of_node = i2c->dev.of_node; if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA)) return -ENODEV; - /* Setup continuous mode, current monitor */ + data = devm_kzalloc(&i2c->dev, sizeof(struct ltc2990_data), GFP_KERNEL); + if (unlikely(!data)) + return -ENOMEM; + + data->i2c = i2c; + + if (of_node) { + ret = of_property_read_u32_array(of_node, "lltc,meas-mode", + data->mode, 2); + if (ret < 0) + return ret; + + if (data->mode[0] & ~LTC2990_MODE0_MASK || + data->mode[1] & ~LTC2990_MODE1_MASK) + return -EINVAL; + } else { + ret = i2c_smbus_read_byte_data(i2c, LTC2990_CONTROL); + if (ret < 0) + return ret; + + data->mode[0] = ret >> LTC2990_MODE0_SHIFT & LTC2990_MODE0_MASK; + data->mode[1] = ret >> LTC2990_MODE1_SHIFT & LTC2990_MODE1_MASK; + } + + /* Setup continuous mode */ ret = i2c_smbus_write_byte_data(i2c, LTC2990_CONTROL, - LTC2990_CONTROL_MEASURE_ALL | - LTC2990_CONTROL_MODE_CURRENT); + data->mode[0] << LTC2990_MODE0_SHIFT | + data->mode[1] << LTC2990_MODE1_SHIFT); if (ret < 0) { dev_err(&i2c->dev, "Error: Failed to set control mode.\n"); return ret; @@ -124,7 +264,7 @@ static int ltc2990_i2c_probe(struct i2c_client *i2c, hwmon_dev = devm_hwmon_device_register_with_groups(&i2c->dev, i2c->name, - i2c, + data, ltc2990_groups); return PTR_ERR_OR_ZERO(hwmon_dev); |