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LTC2945 is a system monitor that measures current, voltage, and power. Signed-off-by: Guenter Roeck <linux@roeck-us.net>
85 lines
2.8 KiB
Plaintext
85 lines
2.8 KiB
Plaintext
Kernel driver ltc2945
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=====================
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Supported chips:
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* Linear Technology LTC2945
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Prefix: 'ltc2945'
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Addresses scanned: -
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Datasheet:
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http://cds.linear.com/docs/en/datasheet/2945fa.pdf
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Author: Guenter Roeck <linux@roeck-us.net>
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Description
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-----------
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The LTC2945 is a rail-to-rail system monitor that measures current, voltage,
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and power consumption.
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Usage Notes
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-----------
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This driver does not probe for LTC2945 devices, since there is no register
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which can be safely used to identify the chip. You will have to instantiate
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the devices explicitly.
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Example: the following will load the driver for an LTC2945 at address 0x10
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on I2C bus #1:
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$ modprobe ltc2945
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$ echo ltc2945 0x10 > /sys/bus/i2c/devices/i2c-1/new_device
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Sysfs entries
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-------------
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Voltage readings provided by this driver are reported as obtained from the ADC
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registers. If a set of voltage divider resistors is installed, calculate the
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real voltage by multiplying the reported value with (R1+R2)/R2, where R1 is the
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value of the divider resistor against the measured voltage and R2 is the value
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of the divider resistor against Ground.
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Current reading provided by this driver is reported as obtained from the ADC
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Current Sense register. The reported value assumes that a 1 mOhm sense resistor
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is installed. If a different sense resistor is installed, calculate the real
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current by dividing the reported value by the sense resistor value in mOhm.
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in1_input VIN voltage (mV). Voltage is measured either at
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SENSE+ or VDD pin depending on chip configuration.
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in1_min Undervoltage threshold
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in1_max Overvoltage threshold
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in1_lowest Lowest measured voltage
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in1_highest Highest measured voltage
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in1_reset_history Write 1 to reset in1 history
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in1_min_alarm Undervoltage alarm
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in1_max_alarm Overvoltage alarm
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in2_input ADIN voltage (mV)
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in2_min Undervoltage threshold
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in2_max Overvoltage threshold
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in2_lowest Lowest measured voltage
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in2_highest Highest measured voltage
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in2_reset_history Write 1 to reset in2 history
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in2_min_alarm Undervoltage alarm
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in2_max_alarm Overvoltage alarm
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curr1_input SENSE current (mA)
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curr1_min Undercurrent threshold
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curr1_max Overcurrent threshold
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curr1_lowest Lowest measured current
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curr1_highest Highest measured current
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curr1_reset_history Write 1 to reset curr1 history
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curr1_min_alarm Undercurrent alarm
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curr1_max_alarm Overcurrent alarm
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power1_input Power (in uW). Power is calculated based on SENSE+/VDD
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voltage or ADIN voltage depending on chip configuration.
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power1_min Low lower threshold
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power1_max High power threshold
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power1_input_lowest Historical minimum power use
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power1_input_highest Historical maximum power use
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power1_reset_history Write 1 to reset power1 history
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power1_min_alarm Low power alarm
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power1_max_alarm High power alarm
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