1Kernel driver it87 2================== 3 4Supported chips: 5 * IT8705F 6 Prefix: 'it87' 7 Addresses scanned: from Super I/O config space (8 I/O ports) 8 Datasheet: Publicly available at the ITE website 9 http://www.ite.com.tw/ 10 * IT8712F 11 Prefix: 'it8712' 12 Addresses scanned: from Super I/O config space (8 I/O ports) 13 Datasheet: Publicly available at the ITE website 14 http://www.ite.com.tw/ 15 * IT8716F 16 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 20 * IT8718F 21 Prefix: 'it8718' 22 Addresses scanned: from Super I/O config space (8 I/O ports) 23 Datasheet: Publicly available at the ITE website 24 http://www.ite.com.tw/product_info/file/pc/IT8718F_V0.2.zip 25 http://www.ite.com.tw/product_info/file/pc/IT8718F_V0%203_(for%20C%20version).zip 26 * SiS950 [clone of IT8705F] 27 Prefix: 'it87' 28 Addresses scanned: from Super I/O config space (8 I/O ports) 29 Datasheet: No longer be available 30 31Authors: 32 Christophe Gauthron <chrisg@0-in.com> 33 Jean Delvare <khali@linux-fr.org> 34 35 36Module Parameters 37----------------- 38 39* update_vbat: int 40 41 0 if vbat should report power on value, 1 if vbat should be updated after 42 each read. Default is 0. On some boards the battery voltage is provided 43 by either the battery or the onboard power supply. Only the first reading 44 at power on will be the actual battery voltage (which the chip does 45 automatically). On other boards the battery voltage is always fed to 46 the chip so can be read at any time. Excessive reading may decrease 47 battery life but no information is given in the datasheet. 48 49* fix_pwm_polarity int 50 51 Force PWM polarity to active high (DANGEROUS). Some chips are 52 misconfigured by BIOS - PWM values would be inverted. This option tries 53 to fix this. Please contact your BIOS manufacturer and ask him for fix. 54 55 56Hardware Interfaces 57------------------- 58 59All the chips suported by this driver are LPC Super-I/O chips, accessed 60through the LPC bus (ISA-like I/O ports). The IT8712F additionally has an 61SMBus interface to the hardware monitoring functions. This driver no 62longer supports this interface though, as it is slower and less reliable 63than the ISA access, and was only available on a small number of 64motherboard models. 65 66 67Description 68----------- 69 70This driver implements support for the IT8705F, IT8712F, IT8716F, 71IT8718F and SiS950 chips. 72 73These chips are 'Super I/O chips', supporting floppy disks, infrared ports, 74joysticks and other miscellaneous stuff. For hardware monitoring, they 75include an 'environment controller' with 3 temperature sensors, 3 fan 76rotation speed sensors, 8 voltage sensors, and associated alarms. 77 78The IT8712F and IT8716F additionally feature VID inputs, used to report 79the Vcore voltage of the processor. The early IT8712F have 5 VID pins, 80the IT8716F and late IT8712F have 6. They are shared with other functions 81though, so the functionality may not be available on a given system. 82The driver dumbly assume it is there. 83 84The IT8718F also features VID inputs (up to 8 pins) but the value is 85stored in the Super-I/O configuration space. Due to technical limitations, 86this value can currently only be read once at initialization time, so 87the driver won't notice and report changes in the VID value. The two 88upper VID bits share their pins with voltage inputs (in5 and in6) so you 89can't have both on a given board. 90 91The IT8716F, IT8718F and later IT8712F revisions have support for 922 additional fans. They are not yet supported by the driver. 93 94The IT8716F and IT8718F, and late IT8712F and IT8705F also have optional 9516-bit tachometer counters for fans 1 to 3. This is better (no more fan 96clock divider mess) but not compatible with the older chips and 97revisions. For now, the driver only uses the 16-bit mode on the 98IT8716F and IT8718F. 99 100Temperatures are measured in degrees Celsius. An alarm is triggered once 101when the Overtemperature Shutdown limit is crossed. 102 103Fan rotation speeds are reported in RPM (rotations per minute). An alarm is 104triggered if the rotation speed has dropped below a programmable limit. When 10516-bit tachometer counters aren't used, fan readings can be divided by 106a programmable divider (1, 2, 4 or 8) to give the readings more range or 107accuracy. With a divider of 2, the lowest representable value is around 1082600 RPM. Not all RPM values can accurately be represented, so some rounding 109is done. 110 111Voltage sensors (also known as IN sensors) report their values in volts. An 112alarm is triggered if the voltage has crossed a programmable minimum or 113maximum limit. Note that minimum in this case always means 'closest to 114zero'; this is important for negative voltage measurements. All voltage 115inputs can measure voltages between 0 and 4.08 volts, with a resolution of 1160.016 volt. The battery voltage in8 does not have limit registers. 117 118The VID lines (IT8712F/IT8716F/IT8718F) encode the core voltage value: 119the voltage level your processor should work with. This is hardcoded by 120the mainboard and/or processor itself. It is a value in volts. 121 122If an alarm triggers, it will remain triggered until the hardware register 123is read at least once. This means that the cause for the alarm may already 124have disappeared! Note that in the current implementation, all hardware 125registers are read whenever any data is read (unless it is less than 1.5 126seconds since the last update). This means that you can easily miss 127once-only alarms. 128 129The IT87xx only updates its values each 1.5 seconds; reading it more often 130will do no harm, but will return 'old' values. 131 132To change sensor N to a thermistor, 'echo 2 > tempN_type' where N is 1, 2, 133or 3. To change sensor N to a thermal diode, 'echo 3 > tempN_type'. 134Give 0 for unused sensor. Any other value is invalid. To configure this at 135startup, consult lm_sensors's /etc/sensors.conf. (2 = thermistor; 1363 = thermal diode) 137 138 139Fan speed control 140----------------- 141 142The fan speed control features are limited to manual PWM mode. Automatic 143"Smart Guardian" mode control handling is not implemented. However 144if you want to go for "manual mode" just write 1 to pwmN_enable. 145 146If you are only able to control the fan speed with very small PWM values, 147try lowering the PWM base frequency (pwm1_freq). Depending on the fan, 148it may give you a somewhat greater control range. The same frequency is 149used to drive all fan outputs, which is why pwm2_freq and pwm3_freq are 150read-only. 151