From 328716bc16b7077ea5f6293c7420247c570d6480 Mon Sep 17 00:00:00 2001 From: Jean Delvare Date: Sat, 14 Aug 2010 21:08:58 +0200 Subject: hwmon: (pc87427) Add support for manual fan speed control Add initial support for PWM outputs of the PC87427 Super-I/O chip. Only mode change and manual fan speed control are supported. Automatic mode configuration isn't supported, and won't be until at least one board is known, which makes uses of the PWM outputs. Signed-off-by: Jean Delvare Acked-by: Guenter Roeck --- Documentation/hwmon/pc87427 | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) (limited to 'Documentation') diff --git a/Documentation/hwmon/pc87427 b/Documentation/hwmon/pc87427 index db5cc1227a83..3282bf39d67d 100644 --- a/Documentation/hwmon/pc87427 +++ b/Documentation/hwmon/pc87427 @@ -20,8 +20,8 @@ The National Semiconductor Super I/O chip includes complete hardware monitoring capabilities. It can monitor up to 18 voltages, 8 fans and 6 temperature sensors. Only the fans are supported at the moment. -This chip also has fan controlling features, which are not yet supported -by this driver either. +This chip also has fan controlling features (up to 4 PWM outputs), +which are partly supported by this driver. The driver assumes that no more than one chip is present, which seems reasonable. @@ -36,3 +36,12 @@ signal. Speeds down to 83 RPM can be measured. An alarm is triggered if the rotation speed drops below a programmable limit. Another alarm is triggered if the speed is too low to be measured (including stalled or missing fan). + + +Fan Speed Control +----------------- + +Fan speed can be controlled by PWM outputs. There are 4 possible modes: +always off, always on, manual and automatic. The latter isn't supported +by the driver: you can only return to that mode if it was the original +setting, and the configuration interface is missing. -- cgit v1.2.2