android_kernel_samsung_msm8976/Documentation/hwmon/emc2103
Steve Glendinning 9df7305b5a hwmon: Add driver for SMSC EMC2103 temperature monitor and fan controller
SMSC's EMC2103 family of temperature/fan controllers have 1
onboard and up to 3 external temperature sensors, and allow
closed-loop control of one fan.  This patch adds support for
them.

Signed-off-by: Steve Glendinning <steve.glendinning@smsc.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-08-14 21:08:54 +02:00

33 lines
1.2 KiB
Text

Kernel driver emc2103
======================
Supported chips:
* SMSC EMC2103
Addresses scanned: I2C 0x2e
Prefix: 'emc2103'
Datasheet: Not public
Authors:
Steve Glendinning <steve.glendinning@smsc.com>
Description
-----------
The Standard Microsystems Corporation (SMSC) EMC2103 chips
contain up to 4 temperature sensors and a single fan controller.
Fan rotation speeds are reported in RPM (rotations per minute). An alarm is
triggered if the rotation speed has dropped below a programmable limit. Fan
readings can be divided by a programmable divider (1, 2, 4 or 8) to give
the readings more range or accuracy. Not all RPM values can accurately be
represented, so some rounding is done. With a divider of 1, the lowest
representable value is 480 RPM.
This driver supports RPM based control, to use this a fan target
should be written to fan1_target and pwm1_enable should be set to 3.
The 2103-2 and 2103-4 variants have a third temperature sensor, which can
be connected to two anti-parallel diodes. These values can be read
as temp3 and temp4. If only one diode is attached to this channel, temp4
will show as "fault". The module parameter "apd=0" can be used to suppress
this 4th channel when anti-parallel diodes are not fitted.