Kernel driver ltc2978

Supported chips:

Author: Guenter Roeck <linux@roeck-us.net>

Description

  • LTC2974 and LTC2975 are quad digital power supply managers.

  • LTC2978 is an octal power supply monitor.

  • LTC2977 is a pin compatible replacement for LTC2978.

  • LTC2980 is a 16-channel Power System Manager, consisting of two LTC2977

  • in a single die. The chip is instantiated and reported as two separate chips

  • on two different I2C bus addresses.

  • LTC3880, LTC3882, LTC3886, and LTC3887 are dual output poly-phase step-down

  • DC/DC controllers.

  • LTC3883 is a single phase step-down DC/DC controller.

  • LTM2987 is a 16-channel Power System Manager with two LTC2977 plus

  • additional components on a single die. The chip is instantiated and reported

  • as two separate chips on two different I2C bus addresses.

  • LTM4675 is a dual 9A or single 18A μModule regulator

  • LTM4676 is a dual 13A or single 26A uModule regulator.

  • LTM4686 is a dual 10A or single 20A uModule regulator.

Usage Notes

This driver does not probe for PMBus devices. You will have to instantiate devices explicitly.

Example: the following commands will load the driver for an LTC2978 at address 0x60 on I2C bus #1:

# modprobe ltc2978
# echo ltc2978 0x60 > /sys/bus/i2c/devices/i2c-1/new_device

Sysfs attributes

in1_label

"vin"

in1_input

Measured input voltage.

in1_min

Minimum input voltage.

in1_max

Maximum input voltage.

LTC2974, LTC2975, LTC2977, LTC2980, LTC2978, and LTM2987 only.

in1_lcrit

Critical minimum input voltage.

LTC2974, LTC2975, LTC2977, LTC2980, LTC2978, and LTM2987 only.

in1_crit

Critical maximum input voltage.

in1_min_alarm

Input voltage low alarm.

in1_max_alarm

Input voltage high alarm.

LTC2974, LTC2975, LTC2977, LTC2980, LTC2978, and LTM2987 only.

in1_lcrit_alarm

Input voltage critical low alarm.

LTC2974, LTC2975, LTC2977, LTC2980, LTC2978, and LTM2987 only.

in1_crit_alarm

Input voltage critical high alarm.

in1_lowest

Lowest input voltage.

LTC2974, LTC2975, LTC2977, LTC2980, LTC2978, and LTM2987 only.

in1_highest

Highest input voltage.

in1_reset_history

Reset input voltage history.

in[N]_label

"vout[1-8]".

  • LTC2974, LTC2975: N=2-5

  • LTC2977, LTC2980, LTM2987: N=2-9

  • LTC2978: N=2-9

  • LTC3880, LTC3882, LTC23886 LTC3887, LTM4675, LTM4676: N=2-3

  • LTC3883: N=2

in[N]_input

Measured output voltage.

in[N]_min

Minimum output voltage.

in[N]_max

Maximum output voltage.

in[N]_lcrit

Critical minimum output voltage.

in[N]_crit

Critical maximum output voltage.

in[N]_min_alarm

Output voltage low alarm.

in[N]_max_alarm

Output voltage high alarm.

in[N]_lcrit_alarm

Output voltage critical low alarm.

in[N]_crit_alarm

Output voltage critical high alarm.

in[N]_lowest

Lowest output voltage.

LTC2974, LTC2975,and LTC2978 only.

in[N]_highest

Highest output voltage.

in[N]_reset_history

Reset output voltage history.

temp[N]_input

Measured temperature.

  • On LTC2974 and LTC2975, temp[1-4] report external temperatures, and temp5 reports the chip temperature.

  • On LTC2977, LTC2980, LTC2978, and LTM2987, only one temperature measurement is supported and reports the chip temperature.

  • On LTC3880, LTC3882, LTC3887, LTM4675, and LTM4676, temp1 and temp2 report external temperatures, and temp3 reports the chip temperature.

  • On LTC3883, temp1 reports an external temperature, and temp2 reports the chip temperature.

temp[N]_min

Mimimum temperature.

LTC2974, LCT2977, LTM2980, LTC2978, and LTM2987 only.

temp[N]_max

Maximum temperature.

temp[N]_lcrit

Critical low temperature.

temp[N]_crit

Critical high temperature.

temp[N]_min_alarm

Temperature low alarm.

LTC2974, LTC2975, LTC2977, LTM2980, LTC2978, and LTM2987 only.

temp[N]_max_alarm

Temperature high alarm.

temp[N]_lcrit_alarm

Temperature critical low alarm.

temp[N]_crit_alarm

Temperature critical high alarm.

temp[N]_lowest

Lowest measured temperature.

  • LTC2974, LTC2975, LTC2977, LTM2980, LTC2978, and LTM2987 only.

  • Not supported for chip temperature sensor on LTC2974 and LTC2975.

temp[N]_highest

Highest measured temperature.

Not supported for chip temperature sensor on LTC2974 and LTC2975.

temp[N]_reset_history

Reset temperature history.

Not supported for chip temperature sensor on LTC2974 and LTC2975.

power1_label

"pin". LTC3883 and LTC3886 only.

power1_input

Measured input power.

power[N]_label

"pout[1-4]".

  • LTC2974, LTC2975: N=1-4

  • LTC2977, LTC2980, LTM2987: Not supported

  • LTC2978: Not supported

  • LTC3880, LTC3882, LTC3886, LTC3887, LTM4675, LTM4676: N=1-2

  • LTC3883: N=2

power[N]_input

Measured output power.

curr1_label

"iin".

LTC3880, LTC3883, LTC3886, LTC3887, LTM4675, and LTM4676 only.

curr1_input

Measured input current.

curr1_max

Maximum input current.

curr1_max_alarm

Input current high alarm.

curr1_highest

Highest input current.

LTC3883 and LTC3886 only.

curr1_reset_history

Reset input current history.

LTC3883 and LTC3886 only.

curr[N]_label

"iout[1-4]".

  • LTC2974, LTC2975: N=1-4

  • LTC2977, LTC2980, LTM2987: not supported

  • LTC2978: not supported

  • LTC3880, LTC3882, LTC3886, LTC3887, LTM4675, LTM4676: N=2-3

  • LTC3883: N=2

curr[N]_input

Measured output current.

curr[N]_max

Maximum output current.

curr[N]_crit

Critical high output current.

curr[N]_lcrit

Critical low output current.

LTC2974 and LTC2975 only.

curr[N]_max_alarm

Output current high alarm.

curr[N]_crit_alarm

Output current critical high alarm.

curr[N]_lcrit_alarm

Output current critical low alarm.

LTC2974 and LTC2975 only.

curr[N]_lowest

Lowest output current.

LTC2974 and LTC2975 only.

curr[N]_highest

Highest output current.

curr[N]_reset_history

Reset output current history.