1*e8ac01e5SArun Saravanan Balachandran.. SPDX-License-Identifier: GPL-2.0-or-later 2*e8ac01e5SArun Saravanan Balachandran 3*e8ac01e5SArun Saravanan BalachandranKernel driver max6620 4*e8ac01e5SArun Saravanan Balachandran===================== 5*e8ac01e5SArun Saravanan Balachandran 6*e8ac01e5SArun Saravanan BalachandranSupported chips: 7*e8ac01e5SArun Saravanan Balachandran 8*e8ac01e5SArun Saravanan Balachandran Maxim MAX6620 9*e8ac01e5SArun Saravanan Balachandran 10*e8ac01e5SArun Saravanan Balachandran Prefix: 'max6620' 11*e8ac01e5SArun Saravanan Balachandran 12*e8ac01e5SArun Saravanan Balachandran Addresses scanned: none 13*e8ac01e5SArun Saravanan Balachandran 14*e8ac01e5SArun Saravanan Balachandran Datasheet: http://pdfserv.maxim-ic.com/en/ds/MAX6620.pdf 15*e8ac01e5SArun Saravanan Balachandran 16*e8ac01e5SArun Saravanan BalachandranAuthors: 17*e8ac01e5SArun Saravanan Balachandran - L\. Grunenberg <contact@lgrunenberg.de> 18*e8ac01e5SArun Saravanan Balachandran - Cumulus Networks <support@cumulusnetworks.com> 19*e8ac01e5SArun Saravanan Balachandran - Shuotian Cheng <shuche@microsoft.com> 20*e8ac01e5SArun Saravanan Balachandran - Arun Saravanan Balachandran <Arun_Saravanan_Balac@dell.com> 21*e8ac01e5SArun Saravanan Balachandran 22*e8ac01e5SArun Saravanan BalachandranDescription 23*e8ac01e5SArun Saravanan Balachandran----------- 24*e8ac01e5SArun Saravanan Balachandran 25*e8ac01e5SArun Saravanan BalachandranThis driver implements support for Maxim MAX6620 fan controller. 26*e8ac01e5SArun Saravanan Balachandran 27*e8ac01e5SArun Saravanan BalachandranThe driver configures the fan controller in RPM mode. To give the readings more 28*e8ac01e5SArun Saravanan Balachandranrange or accuracy, the desired value can be set by a programmable register 29*e8ac01e5SArun Saravanan Balachandran(1, 2, 4, 8, 16 or 32). Set higher values for larger speeds. 30*e8ac01e5SArun Saravanan Balachandran 31*e8ac01e5SArun Saravanan BalachandranThe driver provides the following sensor access in sysfs: 32*e8ac01e5SArun Saravanan Balachandran 33*e8ac01e5SArun Saravanan Balachandran================ ======= ===================================================== 34*e8ac01e5SArun Saravanan Balachandranfan[1-4]_alarm ro Fan alarm. 35*e8ac01e5SArun Saravanan Balachandranfan[1-4]_div rw Sets the nominal RPM range of the fan. Valid values 36*e8ac01e5SArun Saravanan Balachandran are 1, 2, 4, 8, 16 and 32. 37*e8ac01e5SArun Saravanan Balachandranfan[1-4]_input ro Fan speed in RPM. 38*e8ac01e5SArun Saravanan Balachandranfan[1-4]_target rw Desired fan speed in RPM. 39*e8ac01e5SArun Saravanan Balachandran================ ======= ===================================================== 40*e8ac01e5SArun Saravanan Balachandran 41*e8ac01e5SArun Saravanan BalachandranUsage notes 42*e8ac01e5SArun Saravanan Balachandran----------- 43*e8ac01e5SArun Saravanan Balachandran 44*e8ac01e5SArun Saravanan BalachandranThis driver does not auto-detect devices. You will have to instantiate the 45*e8ac01e5SArun Saravanan Balachandrandevices explicitly. Please see Documentation/i2c/instantiating-devices.rst for 46*e8ac01e5SArun Saravanan Balachandrandetails. 47