1Kernel driver max6650
 2=====================
 3
 4Supported chips:
 5
 6  * Maxim MAX6650
 7
 8    Prefix: 'max6650'
 9
10    Addresses scanned: none
11
12    Datasheet: http://pdfserv.maxim-ic.com/en/ds/MAX6650-MAX6651.pdf
13
14  * Maxim MAX6651
15
16    Prefix: 'max6651'
17
18    Addresses scanned: none
19
20    Datasheet: http://pdfserv.maxim-ic.com/en/ds/MAX6650-MAX6651.pdf
21
22Authors:
23    - Hans J. Koch <hjk@hansjkoch.de>
24    - John Morris <john.morris@spirentcom.com>
25    - Claus Gindhart <claus.gindhart@kontron.com>
26
27Description
28-----------
29
30This driver implements support for the Maxim MAX6650 and MAX6651.
31
32The 2 devices are very similar, but the MAX6550 has a reduced feature
33set, e.g. only one fan-input, instead of 4 for the MAX6651.
34
35The driver is not able to distinguish between the 2 devices.
36
37The driver provides the following sensor accesses in sysfs:
38
39=============== ======= =======================================================
40fan1_input	ro	fan tachometer speed in RPM
41fan2_input	ro	"
42fan3_input	ro	"
43fan4_input	ro	"
44fan1_target	rw	desired fan speed in RPM (closed loop mode only)
45pwm1_enable	rw	regulator mode, 0=full on, 1=open loop, 2=closed loop
46			3=off
47pwm1		rw	relative speed (0-255), 255=max. speed.
48			Used in open loop mode only.
49fan1_div	rw	sets the speed range the inputs can handle. Legal
50			values are 1, 2, 4, and 8. Use lower values for
51			faster fans.
52=============== ======= =======================================================
53
54Usage notes
55-----------
56
57This driver does not auto-detect devices. You will have to instantiate the
58devices explicitly. Please see Documentation/i2c/instantiating-devices.rst for
59details.
60
61Module parameters
62-----------------
63
64If your board has a BIOS that initializes the MAX6650/6651 correctly, you can
65simply load your module without parameters. It won't touch the configuration
66registers then. If your board BIOS doesn't initialize the chip, or you want
67different settings, you can set the following parameters:
68
69voltage_12V: 5=5V fan, 12=12V fan, 0=don't change
70prescaler: Possible values are 1,2,4,8,16, or 0 for don't change
71clock: The clock frequency in Hz of the chip the driver should assume [254000]
72
73Please have a look at the MAX6650/6651 data sheet and make sure that you fully
74understand the meaning of these parameters before you attempt to change them.