1.. SPDX-License-Identifier: GPL-2.0-or-later 2 3Kernel driver max6620 4===================== 5 6Supported chips: 7 8 Maxim MAX6620 9 10 Prefix: 'max6620' 11 12 Addresses scanned: none 13 14 Datasheet: http://pdfserv.maxim-ic.com/en/ds/MAX6620.pdf 15 16Authors: 17 - L\. Grunenberg <contact@lgrunenberg.de> 18 - Cumulus Networks <support@cumulusnetworks.com> 19 - Shuotian Cheng <shuche@microsoft.com> 20 - Arun Saravanan Balachandran <Arun_Saravanan_Balac@dell.com> 21 22Description 23----------- 24 25This driver implements support for Maxim MAX6620 fan controller. 26 27The driver configures the fan controller in RPM mode. To give the readings more 28range or accuracy, the desired value can be set by a programmable register 29(1, 2, 4, 8, 16 or 32). Set higher values for larger speeds. 30 31The driver provides the following sensor access in sysfs: 32 33================ ======= ===================================================== 34fan[1-4]_alarm ro Fan alarm. 35fan[1-4]_div rw Sets the nominal RPM range of the fan. Valid values 36 are 1, 2, 4, 8, 16 and 32. 37fan[1-4]_input ro Fan speed in RPM. 38fan[1-4]_target rw Desired fan speed in RPM. 39================ ======= ===================================================== 40 41Usage notes 42----------- 43 44This driver does not auto-detect devices. You will have to instantiate the 45devices explicitly. Please see Documentation/i2c/instantiating-devices.rst for 46details. 47