1Kernel driver max6650 2===================== 3 4Supported chips: 5 * Maxim MAX6650 6 Prefix: 'max6650' 7 Addresses scanned: none 8 Datasheet: http://pdfserv.maxim-ic.com/en/ds/MAX6650-MAX6651.pdf 9 * Maxim MAX6651 10 Prefix: 'max6651' 11 Addresses scanned: none 12 Datasheet: http://pdfserv.maxim-ic.com/en/ds/MAX6650-MAX6651.pdf 13 14Authors: 15 Hans J. Koch <hjk@hansjkoch.de> 16 John Morris <john.morris@spirentcom.com> 17 Claus Gindhart <claus.gindhart@kontron.com> 18 19Description 20----------- 21 22This driver implements support for the Maxim MAX6650 and MAX6651. 23 24The 2 devices are very similar, but the MAX6550 has a reduced feature 25set, e.g. only one fan-input, instead of 4 for the MAX6651. 26 27The driver is not able to distinguish between the 2 devices. 28 29The driver provides the following sensor accesses in sysfs: 30 31fan1_input ro fan tachometer speed in RPM 32fan2_input ro " 33fan3_input ro " 34fan4_input ro " 35fan1_target rw desired fan speed in RPM (closed loop mode only) 36pwm1_enable rw regulator mode, 0=full on, 1=open loop, 2=closed loop 37 3=off 38pwm1 rw relative speed (0-255), 255=max. speed. 39 Used in open loop mode only. 40fan1_div rw sets the speed range the inputs can handle. Legal 41 values are 1, 2, 4, and 8. Use lower values for 42 faster fans. 43 44Usage notes 45----------- 46 47This driver does not auto-detect devices. You will have to instantiate the 48devices explicitly. Please see Documentation/i2c/instantiating-devices for 49details. 50 51Module parameters 52----------------- 53 54If your board has a BIOS that initializes the MAX6650/6651 correctly, you can 55simply load your module without parameters. It won't touch the configuration 56registers then. If your board BIOS doesn't initialize the chip, or you want 57different settings, you can set the following parameters: 58 59voltage_12V: 5=5V fan, 12=12V fan, 0=don't change 60prescaler: Possible values are 1,2,4,8,16, or 0 for don't change 61clock: The clock frequency in Hz of the chip the driver should assume [254000] 62 63Please have a look at the MAX6650/6651 data sheet and make sure that you fully 64understand the meaning of these parameters before you attempt to change them. 65 66