1 Kernel driver pc87360
2 =====================
3
4 Supported chips:
5
6 * National Semiconductor PC87360, PC87363, P
7
8 Prefixes: 'pc87360', 'pc87363', 'pc87364',
9
10 Addresses scanned: none, address read from
11
12 Datasheets: No longer available
13
14 Authors: Jean Delvare <jdelvare@suse.de>
15
16 Thanks to Sandeep Mehta, Tonko de Rooy and Dan
17
18 Thanks to Rudolf Marek for helping me investig
19
20
21 Module Parameters
22 -----------------
23
24 * init int
25 Chip initialization level:
26
27 - 0: None
28 - **1**: Forcibly enable internal voltage
29 except in9
30 - 2: Forcibly enable all voltage and tempe
31 - 3: Forcibly enable all voltage and tempe
32
33 Note that this parameter has no effect for the
34 chips.
35
36 Also note that for the PC87366, initialization
37 all temperature channels, because some of them
38 so they can't be used at the same time.
39
40
41 Description
42 -----------
43
44 The National Semiconductor PC87360 Super I/O c
45 PWM control circuitry for two fans. The PC8736
46 PC87364 chip has monitoring and PWM control fo
47
48 The National Semiconductor PC87365 and PC87366
49 hardware monitoring chipsets, not only control
50 but also monitoring eleven voltage inputs and
51 (PC87366) temperatures.
52
53 =========== ======= ======= ======= =======
54 Chip #vin #fan #pwm #temp
55 =========== ======= ======= ======= =======
56 PC87360 - 2 2 -
57 PC87363 - 2 2 -
58 PC87364 - 3 3 -
59 PC87365 11 3 3 2
60 PC87366 11 3 3 3-4
61 =========== ======= ======= ======= =======
62
63 The driver assumes that no more than one chip
64 standard Super I/O addresses is used (0x2E/0x2
65
66 Fan Monitoring
67 --------------
68
69 Fan rotation speeds are reported in RPM (revol
70 is triggered if the rotation speed has dropped
71 A different alarm is triggered if the fan spee
72
73 Fan readings are affected by a programmable cl
74 readings more range or accuracy. Usually, user
75 but this driver implements dynamic clock divid
76 have to care no more.
77
78 For reference, here are a few values about clo
79
80 =========== =============== ==============
81 slowest accuracy
82 measurable around 3000
83 divider speed (RPM) RPM (RPM)
84 =========== =============== ==============
85 1 1882 18
86 2 941 37
87 4 470 74
88 8 235 150
89 =========== =============== ==============
90
91 For the curious, here is how the values above
92
93 * slowest measurable speed: clock/(255*divide
94 * accuracy around 3000 RPM: 3000^2/clock
95 * highest accurate speed: sqrt(clock*100)
96
97 The clock speed for the PC87360 family is 480
98 RPM as the lowest acceptable accuracy.
99
100 As mentioned above, you don't have to care abo
101
102 Note that not all RPM values can be represente
103 divider is selected. This is not only true for
104 also for the programmable low limits, so don't
105 set, say, fan1_min to 2900 and it finally read
106
107
108 Fan Control
109 -----------
110
111 PWM (pulse width modulation) values range from
112 that the fan is stopped, and 255 meaning that
113
114 Be extremely careful when changing PWM values.
115 non-zero, can stop the fan, which may cause ir
116 hardware if temperature increases too much. Wh
117 step by step and keep an eye on temperatures.
118
119 One user reported problems with PWM. Changing
120 speed readings. No explanation nor fix could b
121
122
123 Temperature Monitoring
124 ----------------------
125
126 Temperatures are reported in degrees Celsius.
127 associated low, high and overtemperature limit
128 alarm when crossed.
129
130 The first two temperature channels are externa
131 only) is internal.
132
133 The PC87366 has three additional temperature c
134 thermistors (as opposed to thermal diodes for
135 channels). For technical reasons, these channe
136 (voltage level monitor) logical device, not th
137 measurement) one. As a consequence, these temp
138 voltages, and converted into temperatures in u
139
140 Note that these three additional channels shar
141 external thermal diode channels, so you (physi
142 the same time. Although it should be possible
143 the documents from National Semiconductor sugg
144 manufacturers should choose one type and stick
145 likely have either channels 1 to 3 (thermal di
146 thermal diode, and thermistors).
147
148
149 Voltage Monitoring
150 ------------------
151
152 Voltages are reported relatively to a referenc
153 external. Some of them (in7:Vsb, in8:Vdd and i
154 internally, you will have to compensate in sen
155 are likely to be divided externally. The meani
156 well as the values of the resistors used for d
157 motherboard manufacturers, so you will have to
158 sensors.conf accordingly. National Semiconduct
159 recommended resistor values for some voltages,
160 room for per motherboard specificities, unfort
161 motherboard manufacturers don't seem to care a
162 recommendations.
163
164 Each voltage measured has associated low and h
165 triggers an alarm when crossed.
166
167 When available, VID inputs are used to provide
168 The driver will default to VRM 9.0, but this c
169 The chipsets can handle two sets of VID inputs
170 the driver will only export one for now. This
171 a need.
172
173
174 General Remarks
175 ---------------
176
177 If an alarm triggers, it will remain triggered
178 is read at least once. This means that the cau
179 have disappeared! Note that all hardware regis
180 data is read (unless it is less than 2 seconds
181 which case cached values are returned instead)
182 a once-only alarm triggers, it may take 2 seco
183 more seconds for it to disappear.
184
185 Monitoring of in9 isn't enabled at lower init
186 channel measures the battery voltage (Vbat). I
187 repeatedly sampling the battery voltage reduce
188 Semiconductor smartly designed their chipset s
189 once every 1024 sampling cycles (that is every
190 sampling rate), so the effect is attenuated, b
191
192
193 Limitations
194 -----------
195
196 The datasheets suggests that some values (fan
197 shouldn't be changed once the monitoring has s
198 recommendation. We'll reconsider if it actuall
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