ltc2945 2.8 KB

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