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Linux kernel mirror (for testing)
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kernel
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linux
1Kernel driver w83627ehf
2=======================
3
4Supported chips:
5 * Winbond W83627EHF/EHG (ISA access ONLY)
6 Prefix: 'w83627ehf'
7 Addresses scanned: ISA address retrieved from Super I/O registers
8 Datasheet:
9 http://www.nuvoton.com.tw/NR/rdonlyres/A6A258F0-F0C9-4F97-81C0-C4D29E7E943E/0/W83627EHF.pdf
10 * Winbond W83627DHG
11 Prefix: 'w83627dhg'
12 Addresses scanned: ISA address retrieved from Super I/O registers
13 Datasheet:
14 http://www.nuvoton.com.tw/NR/rdonlyres/7885623D-A487-4CF9-A47F-30C5F73D6FE6/0/W83627DHG.pdf
15 * Winbond W83627DHG-P
16 Prefix: 'w83627dhg'
17 Addresses scanned: ISA address retrieved from Super I/O registers
18 Datasheet: not available
19 * Winbond W83667HG
20 Prefix: 'w83667hg'
21 Addresses scanned: ISA address retrieved from Super I/O registers
22 Datasheet: not available
23
24Authors:
25 Jean Delvare <khali@linux-fr.org>
26 Yuan Mu (Winbond)
27 Rudolf Marek <r.marek@assembler.cz>
28 David Hubbard <david.c.hubbard@gmail.com>
29 Gong Jun <JGong@nuvoton.com>
30
31Description
32-----------
33
34This driver implements support for the Winbond W83627EHF, W83627EHG,
35W83627DHG, W83627DHG-P and W83667HG super I/O chips. We will refer to them
36collectively as Winbond chips.
37
38The chips implement three temperature sensors, five fan rotation
39speed sensors, ten analog voltage sensors (only nine for the 627DHG), one
40VID (6 pins for the 627EHF/EHG, 8 pins for the 627DHG and 667HG), alarms
41with beep warnings (control unimplemented), and some automatic fan
42regulation strategies (plus manual fan control mode).
43
44Temperatures are measured in degrees Celsius and measurement resolution is 1
45degC for temp1 and 0.5 degC for temp2 and temp3. An alarm is triggered when
46the temperature gets higher than high limit; it stays on until the temperature
47falls below the hysteresis value.
48
49Fan rotation speeds are reported in RPM (rotations per minute). An alarm is
50triggered if the rotation speed has dropped below a programmable limit. Fan
51readings can be divided by a programmable divider (1, 2, 4, 8, 16, 32, 64 or
52128) to give the readings more range or accuracy. The driver sets the most
53suitable fan divisor itself. Some fans might not be present because they
54share pins with other functions.
55
56Voltage sensors (also known as IN sensors) report their values in millivolts.
57An alarm is triggered if the voltage has crossed a programmable minimum
58or maximum limit.
59
60The driver supports automatic fan control mode known as Thermal Cruise.
61In this mode, the chip attempts to keep the measured temperature in a
62predefined temperature range. If the temperature goes out of range, fan
63is driven slower/faster to reach the predefined range again.
64
65The mode works for fan1-fan4. Mapping of temperatures to pwm outputs is as
66follows:
67
68temp1 -> pwm1
69temp2 -> pwm2
70temp3 -> pwm3
71prog -> pwm4 (not on 667HG; the programmable setting is not supported by
72 the driver)
73
74/sys files
75----------
76
77name - this is a standard hwmon device entry. For the W83627EHF and W83627EHG,
78 it is set to "w83627ehf" and for the W83627DHG it is set to "w83627dhg"
79
80pwm[1-4] - this file stores PWM duty cycle or DC value (fan speed) in range:
81 0 (stop) to 255 (full)
82
83pwm[1-4]_enable - this file controls mode of fan/temperature control:
84 * 1 Manual mode, write to pwm file any value 0-255 (full speed)
85 * 2 "Thermal Cruise" mode
86 * 3 "Fan Speed Cruise" mode
87 * 4 "Smart Fan III" mode
88
89pwm[1-4]_mode - controls if output is PWM or DC level
90 * 0 DC output (0 - 12v)
91 * 1 PWM output
92
93Thermal Cruise mode
94-------------------
95
96If the temperature is in the range defined by:
97
98pwm[1-4]_target - set target temperature, unit millidegree Celsius
99 (range 0 - 127000)
100pwm[1-4]_tolerance - tolerance, unit millidegree Celsius (range 0 - 15000)
101
102there are no changes to fan speed. Once the temperature leaves the interval,
103fan speed increases (temp is higher) or decreases if lower than desired.
104There are defined steps and times, but not exported by the driver yet.
105
106pwm[1-4]_min_output - minimum fan speed (range 1 - 255), when the temperature
107 is below defined range.
108pwm[1-4]_stop_time - how many milliseconds [ms] must elapse to switch
109 corresponding fan off. (when the temperature was below
110 defined range).
111
112Note: last two functions are influenced by other control bits, not yet exported
113 by the driver, so a change might not have any effect.
114
115Implementation Details
116----------------------
117
118Future driver development should bear in mind that the following registers have
119different functions on the 627EHF and the 627DHG. Some registers also have
120different power-on default values, but BIOS should already be loading
121appropriate defaults. Note that bank selection must be performed as is currently
122done in the driver for all register addresses.
123
1240x49: only on DHG, selects temperature source for AUX fan, CPU fan0
1250x4a: not completely documented for the EHF and the DHG documentation assigns
126 different behavior to bits 7 and 6, including extending the temperature
127 input selection to SmartFan I, not just SmartFan III. Testing on the EHF
128 will reveal whether they are compatible or not.
129
1300x58: Chip ID: 0xa1=EHF 0xc1=DHG
1310x5e: only on DHG, has bits to enable "current mode" temperature detection and
132 critical temperature protection
1330x45b: only on EHF, bit 3, vin4 alarm (EHF supports 10 inputs, only 9 on DHG)
1340x552: only on EHF, vin4
1350x558: only on EHF, vin4 high limit
1360x559: only on EHF, vin4 low limit
1370x6b: only on DHG, SYS fan critical temperature
1380x6c: only on DHG, CPU fan0 critical temperature
1390x6d: only on DHG, AUX fan critical temperature
1400x6e: only on DHG, CPU fan1 critical temperature
141
1420x50-0x55 and 0x650-0x657 are marked "Test Register" for the EHF, but "Reserved
143 Register" for the DHG
144
145The DHG also supports PECI, where the DHG queries Intel CPU temperatures, and
146the ICH8 southbridge gets that data via PECI from the DHG, so that the
147southbridge drives the fans. And the DHG supports SST, a one-wire serial bus.
148
149The DHG-P has an additional automatic fan speed control mode named Smart Fan
150(TM) III+. This mode is not yet supported by the driver.