54 lines
1.8 KiB
Plaintext
54 lines
1.8 KiB
Plaintext
|
Kernel driver max6650
|
||
|
|
=====================
|
||
|
|
|
||
|
|
Supported chips:
|
||
|
|
* Maxim 6650 / 6651
|
||
|
|
Prefix: 'max6650'
|
||
|
|
Addresses scanned: I2C 0x1b, 0x1f, 0x48, 0x4b
|
||
|
|
Datasheet: http://pdfserv.maxim-ic.com/en/ds/MAX6650-MAX6651.pdf
|
||
|
|
|
||
|
|
Authors:
|
||
|
|
Hans J. Koch <hjk@linutronix.de>
|
||
|
|
John Morris <john.morris@spirentcom.com>
|
||
|
|
Claus Gindhart <claus.gindhart@kontron.com>
|
||
|
|
|
||
|
|
Description
|
||
|
|
-----------
|
||
|
|
|
||
|
|
This driver implements support for the Maxim 6650/6651
|
||
|
|
|
||
|
|
The 2 devices are very similar, but the Maxim 6550 has a reduced feature
|
||
|
|
set, e.g. only one fan-input, instead of 4 for the 6651.
|
||
|
|
|
||
|
|
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
|
||
|
|
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.
|
||
|
|
|
||
|
|
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.
|
||
|
|
|