Based on kernel version 2.6.26. Page generated on 2008-07-16 21:12 EST.
1 Kernel driver w83627ehf 2 ======================= 3 4 Supported chips: 5 * Winbond W83627EHF/EHG/DHG (ISA access ONLY) 6 Prefix: 'w83627ehf' 7 Addresses scanned: ISA address retrieved from Super I/O registers 8 Datasheet: 9 http://www.winbond-usa.com/products/winbond_products/pdfs/PCIC/W83627EHF_%20W83627EHGb.pdf 10 DHG datasheet confidential. 11 12 Authors: 13 Jean Delvare <khali[AT]linux-fr[DOT]org> 14 Yuan Mu (Winbond) 15 Rudolf Marek <r.marek[AT]assembler[DOT]cz> 16 David Hubbard <david.c.hubbard[AT]gmail[DOT]com> 17 18 Description 19 ----------- 20 21 This driver implements support for the Winbond W83627EHF, W83627EHG, and 22 W83627DHG super I/O chips. We will refer to them collectively as Winbond chips. 23 24 The chips implement three temperature sensors, five fan rotation 25 speed sensors, ten analog voltage sensors (only nine for the 627DHG), one 26 VID (6 pins for the 627EHF/EHG, 8 pins for the 627DHG), alarms with beep 27 warnings (control unimplemented), and some automatic fan regulation 28 strategies (plus manual fan control mode). 29 30 Temperatures are measured in degrees Celsius and measurement resolution is 1 31 degC for temp1 and 0.5 degC for temp2 and temp3. An alarm is triggered when 32 the temperature gets higher than high limit; it stays on until the temperature 33 falls below the hysteresis value. 34 35 Fan rotation speeds are reported in RPM (rotations per minute). An alarm is 36 triggered if the rotation speed has dropped below a programmable limit. Fan 37 readings can be divided by a programmable divider (1, 2, 4, 8, 16, 32, 64 or 38 128) to give the readings more range or accuracy. The driver sets the most 39 suitable fan divisor itself. Some fans might not be present because they 40 share pins with other functions. 41 42 Voltage sensors (also known as IN sensors) report their values in millivolts. 43 An alarm is triggered if the voltage has crossed a programmable minimum 44 or maximum limit. 45 46 The driver supports automatic fan control mode known as Thermal Cruise. 47 In this mode, the chip attempts to keep the measured temperature in a 48 predefined temperature range. If the temperature goes out of range, fan 49 is driven slower/faster to reach the predefined range again. 50 51 The mode works for fan1-fan4. Mapping of temperatures to pwm outputs is as 52 follows: 53 54 temp1 -> pwm1 55 temp2 -> pwm2 56 temp3 -> pwm3 57 prog -> pwm4 (the programmable setting is not supported by the driver) 58 59 /sys files 60 ---------- 61 62 name - this is a standard hwmon device entry. For the W83627EHF and W83627EHG, 63 it is set to "w83627ehf" and for the W83627DHG it is set to "w83627dhg" 64 65 pwm[1-4] - this file stores PWM duty cycle or DC value (fan speed) in range: 66 0 (stop) to 255 (full) 67 68 pwm[1-4]_enable - this file controls mode of fan/temperature control: 69 * 1 Manual Mode, write to pwm file any value 0-255 (full speed) 70 * 2 Thermal Cruise 71 72 Thermal Cruise mode 73 ------------------- 74 75 If the temperature is in the range defined by: 76 77 pwm[1-4]_target - set target temperature, unit millidegree Celsius 78 (range 0 - 127000) 79 pwm[1-4]_tolerance - tolerance, unit millidegree Celsius (range 0 - 15000) 80 81 there are no changes to fan speed. Once the temperature leaves the interval, 82 fan speed increases (temp is higher) or decreases if lower than desired. 83 There are defined steps and times, but not exported by the driver yet. 84 85 pwm[1-4]_min_output - minimum fan speed (range 1 - 255), when the temperature 86 is below defined range. 87 pwm[1-4]_stop_time - how many milliseconds [ms] must elapse to switch 88 corresponding fan off. (when the temperature was below 89 defined range). 90 91 Note: last two functions are influenced by other control bits, not yet exported 92 by the driver, so a change might not have any effect. 93 94 Implementation Details 95 ---------------------- 96 97 Future driver development should bear in mind that the following registers have 98 different functions on the 627EHF and the 627DHG. Some registers also have 99 different power-on default values, but BIOS should already be loading 100 appropriate defaults. Note that bank selection must be performed as is currently 101 done in the driver for all register addresses. 102 103 0x49: only on DHG, selects temperature source for AUX fan, CPU fan0 104 0x4a: not completely documented for the EHF and the DHG documentation assigns 105 different behavior to bits 7 and 6, including extending the temperature 106 input selection to SmartFan I, not just SmartFan III. Testing on the EHF 107 will reveal whether they are compatible or not. 108 109 0x58: Chip ID: 0xa1=EHF 0xc1=DHG 110 0x5e: only on DHG, has bits to enable "current mode" temperature detection and 111 critical temperature protection 112 0x45b: only on EHF, bit 3, vin4 alarm (EHF supports 10 inputs, only 9 on DHG) 113 0x552: only on EHF, vin4 114 0x558: only on EHF, vin4 high limit 115 0x559: only on EHF, vin4 low limit 116 0x6b: only on DHG, SYS fan critical temperature 117 0x6c: only on DHG, CPU fan0 critical temperature 118 0x6d: only on DHG, AUX fan critical temperature 119 0x6e: only on DHG, CPU fan1 critical temperature 120 121 0x50-0x55 and 0x650-0x657 are marked "Test Register" for the EHF, but "Reserved 122 Register" for the DHG 123 124 The DHG also supports PECI, where the DHG queries Intel CPU temperatures, and 125 the ICH8 southbridge gets that data via PECI from the DHG, so that the 126 southbridge drives the fans. And the DHG supports SST, a one-wire serial bus.