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Diffstat (limited to 'Documentation/hwmon/vt1211')
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diff --git a/Documentation/hwmon/vt1211 b/Documentation/hwmon/vt1211 deleted file mode 100644 index 77fa633b97a8..000000000000 --- a/Documentation/hwmon/vt1211 +++ /dev/null @@ -1,206 +0,0 @@ -Kernel driver vt1211 -==================== - -Supported chips: - * VIA VT1211 - Prefix: 'vt1211' - Addresses scanned: none, address read from Super-I/O config space - Datasheet: Provided by VIA upon request and under NDA - -Authors: Juerg Haefliger <juergh@gmail.com> - -This driver is based on the driver for kernel 2.4 by Mark D. Studebaker and -its port to kernel 2.6 by Lars Ekman. - -Thanks to Joseph Chan and Fiona Gatt from VIA for providing documentation and -technical support. - - -Module Parameters ------------------ - -* uch_config: int Override the BIOS default universal channel (UCH) - configuration for channels 1-5. - Legal values are in the range of 0-31. Bit 0 maps to - UCH1, bit 1 maps to UCH2 and so on. Setting a bit to 1 - enables the thermal input of that particular UCH and - setting a bit to 0 enables the voltage input. - -* int_mode: int Override the BIOS default temperature interrupt mode. - The only possible value is 0 which forces interrupt - mode 0. In this mode, any pending interrupt is cleared - when the status register is read but is regenerated as - long as the temperature stays above the hysteresis - limit. - -Be aware that overriding BIOS defaults might cause some unwanted side effects! - - -Description ------------ - -The VIA VT1211 Super-I/O chip includes complete hardware monitoring -capabilities. It monitors 2 dedicated temperature sensor inputs (temp1 and -temp2), 1 dedicated voltage (in5) and 2 fans. Additionally, the chip -implements 5 universal input channels (UCH1-5) that can be individually -programmed to either monitor a voltage or a temperature. - -This chip also provides manual and automatic control of fan speeds (according -to the datasheet). The driver only supports automatic control since the manual -mode doesn't seem to work as advertised in the datasheet. In fact I couldn't -get manual mode to work at all! Be aware that automatic mode hasn't been -tested very well (due to the fact that my EPIA M10000 doesn't have the fans -connected to the PWM outputs of the VT1211 :-(). - -The following table shows the relationship between the vt1211 inputs and the -sysfs nodes. - -Sensor Voltage Mode Temp Mode Default Use (from the datasheet) ------- ------------ --------- -------------------------------- -Reading 1 temp1 Intel thermal diode -Reading 3 temp2 Internal thermal diode -UCH1/Reading2 in0 temp3 NTC type thermistor -UCH2 in1 temp4 +2.5V -UCH3 in2 temp5 VccP (processor core) -UCH4 in3 temp6 +5V -UCH5 in4 temp7 +12V -+3.3V in5 Internal VCC (+3.3V) - - -Voltage Monitoring ------------------- - -Voltages are sampled by an 8-bit ADC with a LSB of ~10mV. The supported input -range is thus from 0 to 2.60V. Voltage values outside of this range need -external scaling resistors. This external scaling needs to be compensated for -via compute lines in sensors.conf, like: - -compute inx @*(1+R1/R2), @/(1+R1/R2) - -The board level scaling resistors according to VIA's recommendation are as -follows. And this is of course totally dependent on the actual board -implementation :-) You will have to find documentation for your own -motherboard and edit sensors.conf accordingly. - - Expected -Voltage R1 R2 Divider Raw Value ------------------------------------------------ -+2.5V 2K 10K 1.2 2083 mV -VccP --- --- 1.0 1400 mV (1) -+5V 14K 10K 2.4 2083 mV -+12V 47K 10K 5.7 2105 mV -+3.3V (int) 2K 3.4K 1.588 3300 mV (2) -+3.3V (ext) 6.8K 10K 1.68 1964 mV - -(1) Depending on the CPU (1.4V is for a VIA C3 Nehemiah). -(2) R1 and R2 for 3.3V (int) are internal to the VT1211 chip and the driver - performs the scaling and returns the properly scaled voltage value. - -Each measured voltage has an associated low and high limit which triggers an -alarm when crossed. - - -Temperature Monitoring ----------------------- - -Temperatures are reported in millidegree Celsius. Each measured temperature -has a high limit which triggers an alarm if crossed. There is an associated -hysteresis value with each temperature below which the temperature has to drop -before the alarm is cleared (this is only true for interrupt mode 0). The -interrupt mode can be forced to 0 in case the BIOS doesn't do it -automatically. See the 'Module Parameters' section for details. - -All temperature channels except temp2 are external. Temp2 is the VT1211 -internal thermal diode and the driver does all the scaling for temp2 and -returns the temperature in millidegree Celsius. For the external channels -temp1 and temp3-temp7, scaling depends on the board implementation and needs -to be performed in userspace via sensors.conf. - -Temp1 is an Intel-type thermal diode which requires the following formula to -convert between sysfs readings and real temperatures: - -compute temp1 (@-Offset)/Gain, (@*Gain)+Offset - -According to the VIA VT1211 BIOS porting guide, the following gain and offset -values should be used: - -Diode Type Offset Gain ----------- ------ ---- -Intel CPU 88.638 0.9528 - 65.000 0.9686 *) -VIA C3 Ezra 83.869 0.9528 -VIA C3 Ezra-T 73.869 0.9528 - -*) This is the formula from the lm_sensors 2.10.0 sensors.conf file. I don't -know where it comes from or how it was derived, it's just listed here for -completeness. - -Temp3-temp7 support NTC thermistors. For these channels, the driver returns -the voltages as seen at the individual pins of UCH1-UCH5. The voltage at the -pin (Vpin) is formed by a voltage divider made of the thermistor (Rth) and a -scaling resistor (Rs): - -Vpin = 2200 * Rth / (Rs + Rth) (2200 is the ADC max limit of 2200 mV) - -The equation for the thermistor is as follows (google it if you want to know -more about it): - -Rth = Ro * exp(B * (1 / T - 1 / To)) (To is 298.15K (25C) and Ro is the - nominal resistance at 25C) - -Mingling the above two equations and assuming Rs = Ro and B = 3435 yields the -following formula for sensors.conf: - -compute tempx 1 / (1 / 298.15 - (` (2200 / @ - 1)) / 3435) - 273.15, - 2200 / (1 + (^ (3435 / 298.15 - 3435 / (273.15 + @)))) - - -Fan Speed Control ------------------ - -The VT1211 provides 2 programmable PWM outputs to control the speeds of 2 -fans. Writing a 2 to any of the two pwm[1-2]_enable sysfs nodes will put the -PWM controller in automatic mode. There is only a single controller that -controls both PWM outputs but each PWM output can be individually enabled and -disabled. - -Each PWM has 4 associated distinct output duty-cycles: full, high, low and -off. Full and off are internally hard-wired to 255 (100%) and 0 (0%), -respectively. High and low can be programmed via -pwm[1-2]_auto_point[2-3]_pwm. Each PWM output can be associated with a -different thermal input but - and here's the weird part - only one set of -thermal thresholds exist that controls both PWMs output duty-cycles. The -thermal thresholds are accessible via pwm[1-2]_auto_point[1-4]_temp. Note -that even though there are 2 sets of 4 auto points each, they map to the same -registers in the VT1211 and programming one set is sufficient (actually only -the first set pwm1_auto_point[1-4]_temp is writable, the second set is -read-only). - -PWM Auto Point PWM Output Duty-Cycle ------------------------------------------------- -pwm[1-2]_auto_point4_pwm full speed duty-cycle (hard-wired to 255) -pwm[1-2]_auto_point3_pwm high speed duty-cycle -pwm[1-2]_auto_point2_pwm low speed duty-cycle -pwm[1-2]_auto_point1_pwm off duty-cycle (hard-wired to 0) - -Temp Auto Point Thermal Threshold ---------------------------------------------- -pwm[1-2]_auto_point4_temp full speed temp -pwm[1-2]_auto_point3_temp high speed temp -pwm[1-2]_auto_point2_temp low speed temp -pwm[1-2]_auto_point1_temp off temp - -Long story short, the controller implements the following algorithm to set the -PWM output duty-cycle based on the input temperature: - -Thermal Threshold Output Duty-Cycle - (Rising Temp) (Falling Temp) ----------------------------------------------------------- - full speed duty-cycle full speed duty-cycle -full speed temp - high speed duty-cycle full speed duty-cycle -high speed temp - low speed duty-cycle high speed duty-cycle -low speed temp - off duty-cycle low speed duty-cycle -off temp |