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R.Marek@sh.cvut.cz7f15b662005-05-26 12:42:19 +00001Kernel driver it87
2==================
3
4Supported chips:
5 * IT8705F
6 Prefix: 'it87'
Jean Delvare91749992005-10-08 00:10:00 +02007 Addresses scanned: from Super I/O config space (8 I/O ports)
R.Marek@sh.cvut.cz7f15b662005-05-26 12:42:19 +00008 Datasheet: Publicly available at the ITE website
9 http://www.ite.com.tw/
10 * IT8712F
11 Prefix: 'it8712'
Jean Delvare8e9afcb2006-12-12 18:18:28 +010012 Addresses scanned: from Super I/O config space (8 I/O ports)
R.Marek@sh.cvut.cz7f15b662005-05-26 12:42:19 +000013 Datasheet: Publicly available at the ITE website
14 http://www.ite.com.tw/
Rudolf Marek08a8f6e2007-06-09 10:11:16 -040015 * IT8716F/IT8726F
Jean Delvare17d648b2006-08-28 14:23:46 +020016 Prefix: 'it8716'
17 Addresses scanned: from Super I/O config space (8 I/O ports)
18 Datasheet: Publicly available at the ITE website
19 http://www.ite.com.tw/product_info/file/pc/IT8716F_V0.3.ZIP
Rudolf Marek08a8f6e2007-06-09 10:11:16 -040020 http://www.ite.com.tw/product_info/file/pc/IT8726F_V0.3.pdf
Jean Delvare87673dd2006-08-28 14:37:19 +020021 * IT8718F
22 Prefix: 'it8718'
23 Addresses scanned: from Super I/O config space (8 I/O ports)
24 Datasheet: Publicly available at the ITE website
25 http://www.ite.com.tw/product_info/file/pc/IT8718F_V0.2.zip
26 http://www.ite.com.tw/product_info/file/pc/IT8718F_V0%203_(for%20C%20version).zip
R.Marek@sh.cvut.cz7f15b662005-05-26 12:42:19 +000027 * SiS950 [clone of IT8705F]
Jean Delvare91749992005-10-08 00:10:00 +020028 Prefix: 'it87'
29 Addresses scanned: from Super I/O config space (8 I/O ports)
R.Marek@sh.cvut.cz7f15b662005-05-26 12:42:19 +000030 Datasheet: No longer be available
31
Jean Delvareb19367c2006-08-28 14:39:26 +020032Authors:
Jean Delvaref1d8e332007-11-25 16:14:44 +010033 Christophe Gauthron
Jean Delvareb19367c2006-08-28 14:39:26 +020034 Jean Delvare <khali@linux-fr.org>
R.Marek@sh.cvut.cz7f15b662005-05-26 12:42:19 +000035
36
37Module Parameters
38-----------------
39
40* update_vbat: int
41
42 0 if vbat should report power on value, 1 if vbat should be updated after
43 each read. Default is 0. On some boards the battery voltage is provided
44 by either the battery or the onboard power supply. Only the first reading
45 at power on will be the actual battery voltage (which the chip does
46 automatically). On other boards the battery voltage is always fed to
47 the chip so can be read at any time. Excessive reading may decrease
48 battery life but no information is given in the datasheet.
49
50* fix_pwm_polarity int
51
52 Force PWM polarity to active high (DANGEROUS). Some chips are
53 misconfigured by BIOS - PWM values would be inverted. This option tries
54 to fix this. Please contact your BIOS manufacturer and ask him for fix.
55
Jean Delvare8e9afcb2006-12-12 18:18:28 +010056
57Hardware Interfaces
58-------------------
59
60All the chips suported by this driver are LPC Super-I/O chips, accessed
61through the LPC bus (ISA-like I/O ports). The IT8712F additionally has an
62SMBus interface to the hardware monitoring functions. This driver no
63longer supports this interface though, as it is slower and less reliable
64than the ISA access, and was only available on a small number of
65motherboard models.
66
67
R.Marek@sh.cvut.cz7f15b662005-05-26 12:42:19 +000068Description
69-----------
70
Jean Delvare87673dd2006-08-28 14:37:19 +020071This driver implements support for the IT8705F, IT8712F, IT8716F,
Rudolf Marek08a8f6e2007-06-09 10:11:16 -040072IT8718F, IT8726F and SiS950 chips.
R.Marek@sh.cvut.cz7f15b662005-05-26 12:42:19 +000073
74These chips are 'Super I/O chips', supporting floppy disks, infrared ports,
75joysticks and other miscellaneous stuff. For hardware monitoring, they
76include an 'environment controller' with 3 temperature sensors, 3 fan
77rotation speed sensors, 8 voltage sensors, and associated alarms.
78
Jean Delvare17d648b2006-08-28 14:23:46 +020079The IT8712F and IT8716F additionally feature VID inputs, used to report
80the Vcore voltage of the processor. The early IT8712F have 5 VID pins,
81the IT8716F and late IT8712F have 6. They are shared with other functions
82though, so the functionality may not be available on a given system.
83The driver dumbly assume it is there.
84
Jean Delvare87673dd2006-08-28 14:37:19 +020085The IT8718F also features VID inputs (up to 8 pins) but the value is
86stored in the Super-I/O configuration space. Due to technical limitations,
87this value can currently only be read once at initialization time, so
88the driver won't notice and report changes in the VID value. The two
89upper VID bits share their pins with voltage inputs (in5 and in6) so you
90can't have both on a given board.
Jean Delvare17d648b2006-08-28 14:23:46 +020091
Jean Delvare87673dd2006-08-28 14:37:19 +020092The IT8716F, IT8718F and later IT8712F revisions have support for
Jean Delvarec7f1f712007-09-03 17:11:46 +0200932 additional fans. They are supported by the driver for the IT8716F and
94IT8718F but not for the IT8712F
Jean Delvare87673dd2006-08-28 14:37:19 +020095
96The IT8716F and IT8718F, and late IT8712F and IT8705F also have optional
9716-bit tachometer counters for fans 1 to 3. This is better (no more fan
Jean Delvare17d648b2006-08-28 14:23:46 +020098clock divider mess) but not compatible with the older chips and
99revisions. For now, the driver only uses the 16-bit mode on the
Jean Delvare87673dd2006-08-28 14:37:19 +0200100IT8716F and IT8718F.
Jean Delvare17d648b2006-08-28 14:23:46 +0200101
Rudolf Marek08a8f6e2007-06-09 10:11:16 -0400102The IT8726F is just bit enhanced IT8716F with additional hardware
103for AMD power sequencing. Therefore the chip will appear as IT8716F
104to userspace applications.
105
R.Marek@sh.cvut.cz7f15b662005-05-26 12:42:19 +0000106Temperatures are measured in degrees Celsius. An alarm is triggered once
107when the Overtemperature Shutdown limit is crossed.
108
109Fan rotation speeds are reported in RPM (rotations per minute). An alarm is
Jean Delvare17d648b2006-08-28 14:23:46 +0200110triggered if the rotation speed has dropped below a programmable limit. When
11116-bit tachometer counters aren't used, fan readings can be divided by
112a programmable divider (1, 2, 4 or 8) to give the readings more range or
113accuracy. With a divider of 2, the lowest representable value is around
1142600 RPM. Not all RPM values can accurately be represented, so some rounding
115is done.
R.Marek@sh.cvut.cz7f15b662005-05-26 12:42:19 +0000116
117Voltage sensors (also known as IN sensors) report their values in volts. An
118alarm is triggered if the voltage has crossed a programmable minimum or
119maximum limit. Note that minimum in this case always means 'closest to
120zero'; this is important for negative voltage measurements. All voltage
121inputs can measure voltages between 0 and 4.08 volts, with a resolution of
1220.016 volt. The battery voltage in8 does not have limit registers.
123
Jean Delvare87673dd2006-08-28 14:37:19 +0200124The VID lines (IT8712F/IT8716F/IT8718F) encode the core voltage value:
125the voltage level your processor should work with. This is hardcoded by
126the mainboard and/or processor itself. It is a value in volts.
R.Marek@sh.cvut.cz7f15b662005-05-26 12:42:19 +0000127
128If an alarm triggers, it will remain triggered until the hardware register
129is read at least once. This means that the cause for the alarm may already
130have disappeared! Note that in the current implementation, all hardware
131registers are read whenever any data is read (unless it is less than 1.5
132seconds since the last update). This means that you can easily miss
133once-only alarms.
134
135The IT87xx only updates its values each 1.5 seconds; reading it more often
136will do no harm, but will return 'old' values.
137
138To change sensor N to a thermistor, 'echo 2 > tempN_type' where N is 1, 2,
139or 3. To change sensor N to a thermal diode, 'echo 3 > tempN_type'.
140Give 0 for unused sensor. Any other value is invalid. To configure this at
141startup, consult lm_sensors's /etc/sensors.conf. (2 = thermistor;
1423 = thermal diode)
143
Jean Delvaref8d0c192007-02-14 21:15:02 +0100144
145Fan speed control
146-----------------
147
R.Marek@sh.cvut.cz7f15b662005-05-26 12:42:19 +0000148The fan speed control features are limited to manual PWM mode. Automatic
149"Smart Guardian" mode control handling is not implemented. However
150if you want to go for "manual mode" just write 1 to pwmN_enable.
Jean Delvaref8d0c192007-02-14 21:15:02 +0100151
152If you are only able to control the fan speed with very small PWM values,
153try lowering the PWM base frequency (pwm1_freq). Depending on the fan,
154it may give you a somewhat greater control range. The same frequency is
155used to drive all fan outputs, which is why pwm2_freq and pwm3_freq are
156read-only.