.. 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. ======================= ========================================================