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diff --git a/Documentation/hwmon/max6650.rst b/Documentation/hwmon/max6650.rst new file mode 100644 index 000000000..7952b6eca --- /dev/null +++ b/Documentation/hwmon/max6650.rst @@ -0,0 +1,74 @@ +Kernel driver max6650 +===================== + +Supported chips: + + * Maxim MAX6650 + + Prefix: 'max6650' + + Addresses scanned: none + + Datasheet: http://pdfserv.maxim-ic.com/en/ds/MAX6650-MAX6651.pdf + + * Maxim MAX6651 + + Prefix: 'max6651' + + Addresses scanned: none + + Datasheet: http://pdfserv.maxim-ic.com/en/ds/MAX6650-MAX6651.pdf + +Authors: + - Hans J. Koch <hjk@hansjkoch.de> + - John Morris <john.morris@spirentcom.com> + - Claus Gindhart <claus.gindhart@kontron.com> + +Description +----------- + +This driver implements support for the Maxim MAX6650 and MAX6651. + +The 2 devices are very similar, but the MAX6550 has a reduced feature +set, e.g. only one fan-input, instead of 4 for the MAX6651. + +The driver is not able to distinguish between the 2 devices. + +The driver provides the following sensor accesses in sysfs: + +=============== ======= ======================================================= +fan1_input ro fan tachometer speed in RPM +fan2_input ro " +fan3_input ro " +fan4_input ro " +fan1_target rw desired fan speed in RPM (closed loop mode only) +pwm1_enable rw regulator mode, 0=full on, 1=open loop, 2=closed loop + 3=off +pwm1 rw relative speed (0-255), 255=max. speed. + Used in open loop mode only. +fan1_div rw sets the speed range the inputs can handle. Legal + values are 1, 2, 4, and 8. Use lower values for + faster fans. +=============== ======= ======================================================= + +Usage notes +----------- + +This driver does not auto-detect devices. You will have to instantiate the +devices explicitly. Please see Documentation/i2c/instantiating-devices.rst for +details. + +Module parameters +----------------- + +If your board has a BIOS that initializes the MAX6650/6651 correctly, you can +simply load your module without parameters. It won't touch the configuration +registers then. If your board BIOS doesn't initialize the chip, or you want +different settings, you can set the following parameters: + +voltage_12V: 5=5V fan, 12=12V fan, 0=don't change +prescaler: Possible values are 1,2,4,8,16, or 0 for don't change +clock: The clock frequency in Hz of the chip the driver should assume [254000] + +Please have a look at the MAX6650/6651 data sheet and make sure that you fully +understand the meaning of these parameters before you attempt to change them. |