xref: /linux/Documentation/hwmon/sch5627.rst (revision a36e9f5cfe9eb3a1dce8769c7058251c42705357)
1Kernel driver sch5627
2=====================
3
4Supported chips:
5
6  * SMSC SCH5627
7
8    Prefix: 'sch5627'
9
10    Addresses scanned: none, address read from Super I/O config space
11
12    Datasheet: Application Note available upon request
13
14Author: Hans de Goede <hdegoede@redhat.com>
15
16
17Description
18-----------
19
20SMSC SCH5627 Super I/O chips include complete hardware monitoring
21capabilities. They can monitor up to 5 voltages, 4 fans and 8 temperatures.
22
23In addition, the SCH5627 exports data describing which temperature sensors
24affect the speed of each fan. Setting pwmX_auto_channels_temp to 0 forces
25the corresponding fan to full speed until another value is written.
26
27The SMSC SCH5627 hardware monitoring part also contains an integrated
28watchdog. In order for this watchdog to function some motherboard specific
29initialization most be done by the BIOS, so if the watchdog is not enabled
30by the BIOS the sch5627 driver will not register a watchdog device.
31
32The hardware monitoring part of the SMSC SCH5627 is accessed by talking
33through an embedded microcontroller. An application note describing the
34protocol for communicating with the microcontroller is available upon
35request. Please mail me if you want a copy.
36
37
38Controlling fan speed
39---------------------
40
41The SCH5627 allows for partially controlling the fan speed. If a temperature
42channel excedes tempX_max, all fans are forced to maximum speed. The same is not
43true for tempX_crit, presumably some other measures to cool down the system are
44take in this case.
45In which way the value of fanX_min affects the fan speed is currently unknown.
46