1*4882a593Smuzhiyun.. SPDX-License-Identifier: GPL-2.0-only 2*4882a593Smuzhiyun 3*4882a593SmuzhiyunKernel driver sl28cpld 4*4882a593Smuzhiyun====================== 5*4882a593Smuzhiyun 6*4882a593SmuzhiyunSupported chips: 7*4882a593Smuzhiyun 8*4882a593Smuzhiyun * Kontron sl28cpld 9*4882a593Smuzhiyun 10*4882a593Smuzhiyun Prefix: 'sl28cpld' 11*4882a593Smuzhiyun 12*4882a593Smuzhiyun Datasheet: not available 13*4882a593Smuzhiyun 14*4882a593SmuzhiyunAuthors: Michael Walle <michael@walle.cc> 15*4882a593Smuzhiyun 16*4882a593SmuzhiyunDescription 17*4882a593Smuzhiyun----------- 18*4882a593Smuzhiyun 19*4882a593SmuzhiyunThe sl28cpld is a board management controller which also exposes a hardware 20*4882a593Smuzhiyunmonitoring controller. At the moment this controller supports a single fan 21*4882a593Smuzhiyunsupervisor. In the future there might be other flavours and additional 22*4882a593Smuzhiyunhardware monitoring might be supported. 23*4882a593Smuzhiyun 24*4882a593SmuzhiyunThe fan supervisor has a 7 bit counter register and a counter period of 1 25*4882a593Smuzhiyunsecond. If the 7 bit counter overflows, the supervisor will automatically 26*4882a593Smuzhiyunswitch to x8 mode to support a wider input range at the loss of 27*4882a593Smuzhiyungranularity. 28*4882a593Smuzhiyun 29*4882a593SmuzhiyunSysfs entries 30*4882a593Smuzhiyun------------- 31*4882a593Smuzhiyun 32*4882a593SmuzhiyunThe following attributes are supported. 33*4882a593Smuzhiyun 34*4882a593Smuzhiyun======================= ======================================================== 35*4882a593Smuzhiyunfan1_input Fan RPM. Assuming 2 pulses per revolution. 36*4882a593Smuzhiyun======================= ======================================================== 37