Documentation/hwmon/ltc2945

   1 Kernel driver ltc2945
   2 =====================
   3
   4 Supported chips:
   5   * Linear Technology LTC2945
   6     Prefix: 'ltc2945'
   7     Addresses scanned: -
   8     Datasheet:
   9         http://cds.linear.com/docs/en/datasheet/2945fa.pdf
  10
  11 Author: Guenter Roeck <linux@roeck-us.net>
  12
  13
  14 Description
  15 -----------
  16
  17 The LTC2945  is a rail-to-rail system monitor that measures current, voltage,
  18 and power consumption.
  19
  20
  21 Usage Notes
  22 -----------
  23
  24 This driver does not probe for LTC2945 devices, since there is no register
  25 which can be safely used to identify the chip. You will have to instantiate
  26 the devices explicitly.
  27
  28 Example: the following will load the driver for an LTC2945 at address 0x10
  29 on I2C bus #1:
  30 $ modprobe ltc2945
  31 $ echo ltc2945 0x10 > /sys/bus/i2c/devices/i2c-1/new_device
  32
  33
  34 Sysfs entries
  35 -------------
  36
  37 Voltage readings provided by this driver are reported as obtained from the ADC
  38 registers. If a set of voltage divider resistors is installed, calculate the
  39 real voltage by multiplying the reported value with (R1+R2)/R2, where R1 is the
  40 value of the divider resistor against the measured voltage and R2 is the value
  41 of the divider resistor against Ground.
  42
  43 Current reading provided by this driver is reported as obtained from the ADC
  44 Current Sense register. The reported value assumes that a 1 mOhm sense resistor
  45 is installed. If a different sense resistor is installed, calculate the real
  46 current by dividing the reported value by the sense resistor value in mOhm.
  47
  48 in1_input               VIN voltage (mV). Voltage is measured either at
  49                         SENSE+ or VDD pin depending on chip configuration.
  50 in1_min                 Undervoltage threshold
  51 in1_max                 Overvoltage threshold
  52 in1_lowest              Lowest measured voltage
  53 in1_highest             Highest measured voltage
  54 in1_reset_history       Write 1 to reset in1 history
  55 in1_min_alarm           Undervoltage alarm
  56 in1_max_alarm           Overvoltage alarm
  57
  58 in2_input               ADIN voltage (mV)
  59 in2_min                 Undervoltage threshold
  60 in2_max                 Overvoltage threshold
  61 in2_lowest              Lowest measured voltage
  62 in2_highest             Highest measured voltage
  63 in2_reset_history       Write 1 to reset in2 history
  64 in2_min_alarm           Undervoltage alarm
  65 in2_max_alarm           Overvoltage alarm
  66
  67 curr1_input             SENSE current (mA)
  68 curr1_min               Undercurrent threshold
  69 curr1_max               Overcurrent threshold
  70 curr1_lowest            Lowest measured current
  71 curr1_highest           Highest measured current
  72 curr1_reset_history     Write 1 to reset curr1 history
  73 curr1_min_alarm         Undercurrent alarm
  74 curr1_max_alarm         Overcurrent alarm
  75
  76 power1_input            Power (in uW). Power is calculated based on SENSE+/VDD
  77                         voltage or ADIN voltage depending on chip configuration.
  78 power1_min              Low lower threshold
  79 power1_max              High power threshold
  80 power1_input_lowest     Historical minimum power use
  81 power1_input_highest    Historical maximum power use
  82 power1_reset_history    Write 1 to reset power1 history
  83 power1_min_alarm        Low power alarm
  84 power1_max_alarm        High power alarm