1 Kernel driver w83627ehf
2 =======================
5 * Winbond W83627EHF/EHG (ISA access ONLY)
7 Addresses scanned: ISA address retrieved from Super I/O registers
8 Datasheet: not available
11 Addresses scanned: ISA address retrieved from Super I/O registers
12 Datasheet: not available
15 Addresses scanned: ISA address retrieved from Super I/O registers
16 Datasheet: not available
19 Addresses scanned: ISA address retrieved from Super I/O registers
20 Datasheet: not available
23 Addresses scanned: ISA address retrieved from Super I/O registers
24 Datasheet: Available from Nuvoton upon request
27 Jean Delvare <khali@linux-fr.org>
29 Rudolf Marek <r.marek@assembler.cz>
30 David Hubbard <david.c.hubbard@gmail.com>
31 Gong Jun <JGong@nuvoton.com>
36 This driver implements support for the Winbond W83627EHF, W83627EHG,
37 W83627DHG, W83627DHG-P, W83667HG and W83667HG-B super I/O chips.
38 We will refer to them collectively as Winbond chips.
40 The chips implement three temperature sensors (up to four for 667HG-B),
41 five fan rotation speed sensors, ten analog voltage sensors (only nine for the
42 627DHG), one VID (6 pins for the 627EHF/EHG, 8 pins for the 627DHG and 667HG),
43 alarms with beep warnings (control unimplemented), and some automatic fan
44 regulation strategies (plus manual fan control mode).
46 The temperature sensor sources on W82677HG-B are configurable. temp4 is only
47 reported if its temperature source differs from the temperature sources of the
48 other three temperature sensors. The configured source for each of the
49 temperature sensors is reported in tempX_label.
51 Temperatures are measured in degrees Celsius and measurement resolution is 1
52 degC for temp1 and temp4, and 0.5 degC for temp2 and temp3. An alarm is
53 triggered when the temperature gets higher than high limit; it stays on until
54 the temperature falls below the hysteresis value.
56 Fan rotation speeds are reported in RPM (rotations per minute). An alarm is
57 triggered if the rotation speed has dropped below a programmable limit. Fan
58 readings can be divided by a programmable divider (1, 2, 4, 8, 16, 32, 64 or
59 128) to give the readings more range or accuracy. The driver sets the most
60 suitable fan divisor itself. Some fans might not be present because they
61 share pins with other functions.
63 Voltage sensors (also known as IN sensors) report their values in millivolts.
64 An alarm is triggered if the voltage has crossed a programmable minimum
67 The driver supports automatic fan control mode known as Thermal Cruise.
68 In this mode, the chip attempts to keep the measured temperature in a
69 predefined temperature range. If the temperature goes out of range, fan
70 is driven slower/faster to reach the predefined range again.
72 The mode works for fan1-fan4. Mapping of temperatures to pwm outputs is as
78 prog -> pwm4 (not on 667HG and 667HG-B; the programmable setting is not
79 supported by the driver)
84 name - this is a standard hwmon device entry. For the W83627EHF and W83627EHG,
85 it is set to "w83627ehf", for the W83627DHG it is set to "w83627dhg",
86 and for the W83667HG it is set to "w83667hg".
88 pwm[1-4] - this file stores PWM duty cycle or DC value (fan speed) in range:
89 0 (stop) to 255 (full)
91 pwm[1-4]_enable - this file controls mode of fan/temperature control:
92 * 1 Manual mode, write to pwm file any value 0-255 (full speed)
93 * 2 "Thermal Cruise" mode
94 * 3 "Fan Speed Cruise" mode
95 * 4 "Smart Fan III" mode
97 pwm[1-4]_mode - controls if output is PWM or DC level
98 * 0 DC output (0 - 12v)
104 If the temperature is in the range defined by:
106 pwm[1-4]_target - set target temperature, unit millidegree Celsius
108 pwm[1-4]_tolerance - tolerance, unit millidegree Celsius (range 0 - 15000)
110 there are no changes to fan speed. Once the temperature leaves the interval,
111 fan speed increases (temp is higher) or decreases if lower than desired.
112 There are defined steps and times, but not exported by the driver yet.
114 pwm[1-4]_min_output - minimum fan speed (range 1 - 255), when the temperature
115 is below defined range.
116 pwm[1-4]_stop_time - how many milliseconds [ms] must elapse to switch
117 corresponding fan off. (when the temperature was below
120 Note: last two functions are influenced by other control bits, not yet exported
121 by the driver, so a change might not have any effect.
123 Implementation Details
124 ----------------------
126 Future driver development should bear in mind that the following registers have
127 different functions on the 627EHF and the 627DHG. Some registers also have
128 different power-on default values, but BIOS should already be loading
129 appropriate defaults. Note that bank selection must be performed as is currently
130 done in the driver for all register addresses.
132 0x49: only on DHG, selects temperature source for AUX fan, CPU fan0
133 0x4a: not completely documented for the EHF and the DHG documentation assigns
134 different behavior to bits 7 and 6, including extending the temperature
135 input selection to SmartFan I, not just SmartFan III. Testing on the EHF
136 will reveal whether they are compatible or not.
138 0x58: Chip ID: 0xa1=EHF 0xc1=DHG
139 0x5e: only on DHG, has bits to enable "current mode" temperature detection and
140 critical temperature protection
141 0x45b: only on EHF, bit 3, vin4 alarm (EHF supports 10 inputs, only 9 on DHG)
142 0x552: only on EHF, vin4
143 0x558: only on EHF, vin4 high limit
144 0x559: only on EHF, vin4 low limit
145 0x6b: only on DHG, SYS fan critical temperature
146 0x6c: only on DHG, CPU fan0 critical temperature
147 0x6d: only on DHG, AUX fan critical temperature
148 0x6e: only on DHG, CPU fan1 critical temperature
150 0x50-0x55 and 0x650-0x657 are marked "Test Register" for the EHF, but "Reserved
151 Register" for the DHG
153 The DHG also supports PECI, where the DHG queries Intel CPU temperatures, and
154 the ICH8 southbridge gets that data via PECI from the DHG, so that the
155 southbridge drives the fans. And the DHG supports SST, a one-wire serial bus.
157 The DHG-P has an additional automatic fan speed control mode named Smart Fan
158 (TM) III+. This mode is not yet supported by the driver.