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Based on kernel version 3.16. Page generated on 2014-08-06 21:39 EST.

1	Kernel driver gl518sm
2	=====================
3	
4	Supported chips:
5	  * Genesys Logic GL518SM release 0x00
6	    Prefix: 'gl518sm'
7	    Addresses scanned: I2C 0x2c and 0x2d
8	  * Genesys Logic GL518SM release 0x80
9	    Prefix: 'gl518sm'
10	    Addresses scanned: I2C 0x2c and 0x2d
11	    Datasheet: http://www.genesyslogic.com/
12	
13	Authors:
14	        Frodo Looijaard <frodol@dds.nl>,
15	        Kyösti Mälkki <kmalkki@cc.hut.fi>
16	        Hong-Gunn Chew <hglinux@gunnet.org>
17	        Jean Delvare <jdelvare@suse.de>
18	
19	Description
20	-----------
21	
22	IMPORTANT:
23	
24	For the revision 0x00 chip, the in0, in1, and in2  values (+5V, +3V,
25	and +12V) CANNOT be read. This is a limitation of the chip, not the driver.
26	
27	This driver supports the Genesys Logic GL518SM chip. There are at least
28	two revision of this chip, which we call revision 0x00 and 0x80. Revision
29	0x80 chips support the reading of all voltages and revision 0x00 only
30	for VIN3.
31	
32	The GL518SM implements one temperature sensor, two fan rotation speed
33	sensors, and four voltage sensors. It can report alarms through the
34	computer speakers.
35	
36	Temperatures are measured in degrees Celsius. An alarm goes off while the
37	temperature is above the over temperature limit, and has not yet dropped
38	below the hysteresis limit. The alarm always reflects the current
39	situation. Measurements are guaranteed between -10 degrees and +110
40	degrees, with a accuracy of +/-3 degrees.
41	
42	Rotation speeds are reported in RPM (rotations per minute). An alarm is
43	triggered if the rotation speed has dropped below a programmable limit. In
44	case when you have selected to turn fan1 off, no fan1 alarm is triggered.
45	
46	Fan readings can be divided by a programmable divider (1, 2, 4 or 8) to
47	give the readings more range or accuracy.  Not all RPM values can
48	accurately be represented, so some rounding is done. With a divider
49	of 2, the lowest representable value is around 1900 RPM.
50	
51	Voltage sensors (also known as VIN sensors) report their values in volts.
52	An alarm is triggered if the voltage has crossed a programmable minimum or
53	maximum limit. Note that minimum in this case always means 'closest to
54	zero'; this is important for negative voltage measurements. The VDD input
55	measures voltages between 0.000 and 5.865 volt, with a resolution of 0.023
56	volt. The other inputs measure voltages between 0.000 and 4.845 volt, with
57	a resolution of 0.019 volt. Note that revision 0x00 chips do not support
58	reading the current voltage of any input except for VIN3; limit setting and
59	alarms work fine, though.
60	
61	When an alarm is triggered, you can be warned by a beeping signal through your
62	computer speaker. It is possible to enable all beeping globally, or only the
63	beeping for some alarms.
64	
65	If an alarm triggers, it will remain triggered until the hardware register
66	is read at least once (except for temperature alarms). This means that the
67	cause for the alarm may already have disappeared! Note that in the current
68	implementation, all hardware registers are read whenever any data is read
69	(unless it is less than 1.5 seconds since the last update). This means that
70	you can easily miss once-only alarms.
71	
72	The GL518SM only updates its values each 1.5 seconds; reading it more often
73	will do no harm, but will return 'old' values.
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