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.. SPDX-License-Identifier: GPL-2.0-only

Kernel driver sl28cpld
======================

Supported chips:

   * Kontron sl28cpld

     Prefix: 'sl28cpld'

     Datasheet: not available

Authors: Michael Walle <michael@walle.cc>

Description
-----------

The sl28cpld is a board management controller which also exposes a hardware
monitoring controller. At the moment this controller supports a single fan
supervisor. In the future there might be other flavours and additional
hardware monitoring might be supported.

The fan supervisor has a 7 bit counter register and a counter period of 1
second. If the 7 bit counter overflows, the supervisor will automatically
switch to x8 mode to support a wider input range at the loss of
granularity.

Sysfs entries
-------------

The following attributes are supported.

======================= ========================================================
fan1_input		Fan RPM. Assuming 2 pulses per revolution.
======================= ========================================================