Kernel driver zl6100

Supported chips:

Author: Guenter Roeck <>


This driver supports hardware monitoring for Intersil / Zilker Labs ZL6100 and compatible digital DC-DC controllers.

The driver is a client driver to the core PMBus driver. Please see Kernel driver pmbus and Documentation.hwmon/pmbus-core for details on PMBus client drivers.

Usage Notes

This driver does not auto-detect devices. You will have to instantiate the devices explicitly. Please see How to instantiate I2C devices for details.


Do not access chip registers using the i2cdump command, and do not use any of the i2ctools commands on a command register used to save and restore configuration data (0x11, 0x12, 0x15, 0x16, and 0xf4). The chips supported by this driver interpret any access to those command registers (including read commands) as request to execute the command in question. Unless write accesses to those registers are protected, this may result in power loss, board resets, and/or Flash corruption. Worst case, your board may turn into a brick.

Platform data support

The driver supports standard PMBus driver platform data.

Module parameters


Intersil/Zilker Labs DC-DC controllers require a minimum interval between I2C bus accesses. According to Intersil, the minimum interval is 2 ms, though 1 ms appears to be sufficient and has not caused any problems in testing. The problem is known to affect all currently supported chips. For manual override, the driver provides a writeable module parameter, ‘delay’, which can be used to set the interval to a value between 0 and 65,535 microseconds.

Sysfs entries

The following attributes are supported. Limits are read-write; all other attributes are read-only.

in1_label “vin”
in1_input Measured input voltage.
in1_min Minimum input voltage.
in1_max Maximum input voltage.
in1_lcrit Critical minimum input voltage.
in1_crit Critical maximum input voltage.
in1_min_alarm Input voltage low alarm.
in1_max_alarm Input voltage high alarm.
in1_lcrit_alarm Input voltage critical low alarm.
in1_crit_alarm Input voltage critical high alarm.
in2_label “vmon”
in2_input Measured voltage on VMON (ZL2004) or VDRV (ZL9101M, ZL9117M) pin. Reported voltage is 16x the voltage on the pin (adjusted internally by the chip).
in2_lcrit Critical minimum VMON/VDRV Voltage.
in2_crit Critical maximum VMON/VDRV voltage.
in2_lcrit_alarm VMON/VDRV voltage critical low alarm.

VMON/VDRV voltage critical high alarm.

vmon attributes are supported on ZL2004, ZL9101M, and ZL9117M only.

inX_label “vout1”
inX_input Measured output voltage.
inX_lcrit Critical minimum output Voltage.
inX_crit Critical maximum output voltage.
inX_lcrit_alarm Critical output voltage critical low alarm.

Critical output voltage critical high alarm.

X is 3 for ZL2004, ZL9101M, and ZL9117M, 2 otherwise.

curr1_label “iout1”
curr1_input Measured output current.
curr1_lcrit Critical minimum output current.
curr1_crit Critical maximum output current.
curr1_lcrit_alarm Output current critical low alarm.
curr1_crit_alarm Output current critical high alarm.
temp[12]_input Measured temperature.
temp[12]_min Minimum temperature.
temp[12]_max Maximum temperature.
temp[12]_lcrit Critical low temperature.
temp[12]_crit Critical high temperature.
temp[12]_min_alarm Chip temperature low alarm.
temp[12]_max_alarm Chip temperature high alarm.
temp[12]_lcrit_alarm Chip temperature critical low alarm.
temp[12]_crit_alarm Chip temperature critical high alarm.