diff options
Diffstat (limited to 'Documentation/laptops')
-rw-r--r-- | Documentation/laptops/thinkpad-acpi.txt | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/Documentation/laptops/thinkpad-acpi.txt b/Documentation/laptops/thinkpad-acpi.txt index f2ff638cce8d..0d5e91379ae8 100644 --- a/Documentation/laptops/thinkpad-acpi.txt +++ b/Documentation/laptops/thinkpad-acpi.txt @@ -1269,7 +1269,7 @@ Fan control and monitoring: fan speed, fan enable/disable procfs: /proc/acpi/ibm/fan sysfs device attributes: (hwmon "thinkpad") fan1_input, pwm1, - pwm1_enable + pwm1_enable, fan2_input sysfs hwmon driver attributes: fan_watchdog NOTE NOTE NOTE: fan control operations are disabled by default for @@ -1282,6 +1282,9 @@ from the hardware registers of the embedded controller. This is known to work on later R, T, X and Z series ThinkPads but may show a bogus value on other models. +Some Lenovo ThinkPads support a secondary fan. This fan cannot be +controlled separately, it shares the main fan control. + Fan levels: Most ThinkPad fans work in "levels" at the firmware interface. Level 0 @@ -1412,6 +1415,11 @@ hwmon device attribute fan1_input: which can take up to two minutes. May return rubbish on older ThinkPads. +hwmon device attribute fan2_input: + Fan tachometer reading, in RPM, for the secondary fan. + Available only on some ThinkPads. If the secondary fan is + not installed, will always read 0. + hwmon driver attribute fan_watchdog: Fan safety watchdog timer interval, in seconds. Minimum is 1 second, maximum is 120 seconds. 0 disables the watchdog. |