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 How to instantiate I2C devices 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.