Kernel driver ltc2945
Supported chips:
Linear Technology LTC2945
Prefix: 'ltc2945'
Addresses scanned: -
Datasheet:
Author: Guenter Roeck <linux@roeck-us.net>
Description
The LTC2945 is a rail-to-rail system monitor that measures current, voltage, and power consumption.
Usage Notes
This driver does not probe for LTC2945 devices, since there is no register which can be safely used to identify the chip. You will have to instantiate the devices explicitly.
Example: the following will load the driver for an LTC2945 at address 0x10 on I2C bus #1:
$ modprobe ltc2945 $ echo ltc2945 0x10 > /sys/bus/i2c/devices/i2c-1/new_device
Sysfs entries
Voltage readings provided by this driver are reported as obtained from the ADC registers. If a set of voltage divider resistors is installed, calculate the real voltage by multiplying the reported value with (R1+R2)/R2, where R1 is the value of the divider resistor against the measured voltage and R2 is the value of the divider resistor against Ground.
Current reading provided by this driver is reported as obtained from the ADC Current Sense register. The reported value assumes that a 1 mOhm sense resistor is installed. If a different sense resistor is installed, calculate the real current by dividing the reported value by the sense resistor value in mOhm.
| in1_input | VIN voltage (mV). Voltage is measured either at SENSE+ or VDD pin depending on chip configuration. |
| 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 |
| in2_input | ADIN 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 |
| 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 |
| power1_input | Power (in uW). Power is calculated based on SENSE+/VDD voltage or ADIN voltage depending on chip configuration. |
| power1_min | Low lower 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 |