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
37pwm1		rw	relative speed (0-255), 255=max. speed.
38			Used in open loop mode only.
39fan1_div	rw	sets the speed range the inputs can handle. Legal
40			values are 1, 2, 4, and 8. Use lower values for
41			faster fans.
42
43Usage notes
44-----------
45
46This driver does not auto-detect devices. You will have to instantiate the
47devices explicitly. Please see Documentation/i2c/instantiating-devices for
48details.
49
50Module parameters
51-----------------
52
53If your board has a BIOS that initializes the MAX6650/6651 correctly, you can
54simply load your module without parameters. It won't touch the configuration
55registers then. If your board BIOS doesn't initialize the chip, or you want
56different settings, you can set the following parameters:
57
58voltage_12V: 5=5V fan, 12=12V fan, 0=don't change
59prescaler: Possible values are 1,2,4,8,16, or 0 for don't change
60clock: The clock frequency in Hz of the chip the driver should assume [254000]
61
62Please have a look at the MAX6650/6651 data sheet and make sure that you fully
63understand the meaning of these parameters before you attempt to change them.
64
65