1 Kernel driver lm85
2 ==================
3
4 Supported chips:
5
6 * National Semiconductor LM85 (B and C versi
7
8 Prefix: 'lm85b' or 'lm85c'
9
10 Addresses scanned: I2C 0x2c, 0x2d, 0x2e
11
12 Datasheet: http://www.national.com/pf/LM/L
13
14 * Texas Instruments LM96000
15
16 Prefix: 'lm9600'
17
18 Addresses scanned: I2C 0x2c, 0x2d, 0x2e
19
20 Datasheet: https://www.ti.com/lit/ds/symli
21
22 * Analog Devices ADM1027
23
24 Prefix: 'adm1027'
25
26 Addresses scanned: I2C 0x2c, 0x2d, 0x2e
27
28 Datasheet: https://www.onsemi.com/PowerSol
29
30 * Analog Devices ADT7463
31
32 Prefix: 'adt7463'
33
34 Addresses scanned: I2C 0x2c, 0x2d, 0x2e
35
36 Datasheet: https://www.onsemi.com/PowerSol
37
38 * Analog Devices ADT7468
39
40 Prefix: 'adt7468'
41
42 Addresses scanned: I2C 0x2c, 0x2d, 0x2e
43
44 Datasheet: https://www.onsemi.com/PowerSol
45
46 * SMSC EMC6D100, SMSC EMC6D101
47
48 Prefix: 'emc6d100'
49
50 Addresses scanned: I2C 0x2c, 0x2d, 0x2e
51
52 Datasheet: http://www.smsc.com/media/Downl
53
54 * SMSC EMC6D102
55
56 Prefix: 'emc6d102'
57
58 Addresses scanned: I2C 0x2c, 0x2d, 0x2e
59
60 Datasheet: http://www.smsc.com/main/catalo
61
62 * SMSC EMC6D103
63
64 Prefix: 'emc6d103'
65
66 Addresses scanned: I2C 0x2c, 0x2d, 0x2e
67
68 Datasheet: http://www.smsc.com/main/catalo
69
70 * SMSC EMC6D103S
71
72 Prefix: 'emc6d103s'
73
74 Addresses scanned: I2C 0x2c, 0x2d, 0x2e
75
76 Datasheet: http://www.smsc.com/main/catalo
77
78 Authors:
79 - Philip Pokorny <ppokorny@penguincomput
80 - Frodo Looijaard <frodol@dds.nl>,
81 - Richard Barrington <rich_b_nz@clear.ne
82 - Margit Schubert-While <margitsw@t-onli
83 - Justin Thiessen <jthiessen@penguincomp
84
85 Description
86 -----------
87
88 This driver implements support for the Nationa
89 compatible chips including the Analog Devices
90 SMSC EMC6D10x chips family.
91
92 The LM85 uses the 2-wire interface compatible
93 specification. Using an analog to digital conv
94 temperatures and five (5) voltages. It has fou
95 measuring fan speed. Five (5) digital inputs a
96 VID signals from the processor to the VRM. Las
97 outputs that can be used to control fan speed.
98
99 The voltage inputs have internal scaling resis
100 voltage can be measured without external resis
101
102 2.5V, 3.3V, 5V, 12V, and CPU core voltage (2
103
104 The temperatures measured are one internal dio
105 Remote 1 is generally the CPU temperature. The
106 measure a thermal diode like the one in a Pent
107 423 or socket 478 package. They can also measu
108 transistor like the 2N3904.
109
110 A sophisticated control system for the PWM out
111 LM85 that allows fan speed to be adjusted auto
112 three temperature sensors. Each PWM output is
113 programmable. Once configured, the LM85 will a
114 response to the measured temperatures without
115 This feature can also be disabled for manual c
116
117 Each of the measured inputs (voltage, temperat
118 corresponding high/low limit values. The LM85
119 measured value exceeds either limit.
120
121 The LM85 samples all inputs continuously. The
122 the registers more often than once a second. F
123 only read once each 5 minutes. There is twice
124 measurements, so this would seem to be a worth
125
126 Special Features
127 ----------------
128
129 The LM85 has four fan speed monitoring modes.
130 Both have special circuitry to compensate for
131 TACH signal from the fans. The ADM1027 can be
132 speed of a two wire fan, but the input conditi
133 for 3-wire and 2-wire mode. For this reason, t
134 exposed to user control. The BIOS should initi
135 mode. If you've designed your own ADM1027, you
136 init_client function and add an insmod paramet
137
138 To smooth the response of fans to changes in t
139 optional filter for smoothing temperatures. Th
140 config option but uses it to rate limit the ch
141
142 The ADM1027, ADT7463 and ADT7468 have a 10-bit
143 measure temperatures with 0.25 degC resolution
144 to the temperature readings that is automatica
145 measurement. This offset can be used to zero o
146 and placement. The documentation says that the
147 steps, but in initial testing of the ADM1027 i
148 Devices has confirmed this "bug". The ADT7463
149 described in the documentation. The current lm
150 offset register.
151
152 The ADT7468 has a high-frequency PWM mode, whe
153 driven by a 22.5 kHz clock. This is a global m
154 which means that setting any PWM frequency abo
155 all 3 PWM outputs to a 22.5 kHz frequency. Con
156 frequency below 11.3 kHz will switch all 3 PWM
157 between 10 and 100 Hz, which can then be tuned
158
159 See the vendor datasheets for more information
160 from National (AN-1260) with some additional i
161 The Analog Devices datasheet is very detailed
162 determining an optimal configuration for the a
163
164 The SMSC EMC6D100 & EMC6D101 monitor external
165 fan speeds. They use this monitoring capabilit
166 of limit conditions and can automatically cont
167 fans in a PC or embedded system. The EMC6D101,
168 package, and the EMC6D100, available in a 28-p
169 to be register compatible. The EMC6D100 offers
170 EMC6D101 plus additional voltage monitoring an
171 Unfortunately it is not possible to distinguis
172 versions on register level so these additional
173 zero. EMC6D102 and EMC6D103 feature additional
174 of voltage and temperature channels.
175
176 SMSC EMC6D103S is similar to EMC6D103, but doe
177 and temp#_auto_temp_off.
178
179 The LM96000 supports additional high frequency
180 25.7 kHz, 27.7 kHz and 30 kHz), which can be c
181
182 Hardware Configurations
183 -----------------------
184
185 The LM85 can be jumpered for 3 different SMBus
186 no other hardware configuration options for th
187
188 The lm85 driver detects both LM85B and LM85C r
189 datasheet for a complete description of the di
190 identifying the chip, the driver behaves no di
191 these two chips. The LM85B is recommended for
192
193 The ADM1027, ADT7463 and ADT7468 chips have an
194 that can be used to signal the chipset in case
195 temperature sensors fail. Individual sensor in
196 they won't trigger SMBALERT. The SMBALERT outp
197 of the other functions (PWM2 or IN0). This fun
198 in current driver.
199
200 The ADT7463 and ADT7468 also have an optional
201 be connected to the processor PROC_HOT output.
202 control dynamic Tmin feature can be enabled to
203 within spec (just?!) with the least possible f
204
205 Configuration Notes
206 -------------------
207
208 Besides standard interfaces driver adds follow
209
210 * Temperatures and Zones
211
212 Each temperature sensor is associated with a Z
213 sensors and therefore three zones (# 1, 2 and
214 temperature configuration points:
215
216 * temp#_auto_temp_off
217 - temperature below which fans should
218 * temp#_auto_temp_min
219 - temperature over which fans start to
220 * temp#_auto_temp_max
221 - temperature when fans spin at full s
222 * temp#_auto_temp_crit
223 - temperature when all fans will run f
224
225 PWM Control
226 ^^^^^^^^^^^
227
228 There are three PWM outputs. The LM85 datashee
229 pwm3 output control both fan3 and fan4. Each P
230 configured and assigned to a zone for its cont
231 configured individually according to the follo
232
233 * pwm#_auto_pwm_min
234 - this specifies the PWM value for tem
235 temperature. (PWM value from 0 to 25
236
237 * pwm#_auto_pwm_minctl
238 - this flags selects for temp#_auto_te
239 the behaviour of fans. Write 1 to le
240 pwm#_auto_pwm_min or write 0 to let
241
242 .. note::
243
244 It has been reported that there is a b
245 the flag to be associated with the zon
246 contradicts all the published document
247 in this case actually affects all PWMs
248
249 PWM Controlling Zone selection
250 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
251
252 * pwm#_auto_channels
253 - controls zone that is associated wit
254
255 Configuration choices:
256
257 ========== ===================================
258 Value Meaning
259 ========== ===================================
260 1 Controlled by Zone 1
261 2 Controlled by Zone 2
262 3 Controlled by Zone 3
263 23 Controlled by higher temp of Zone 2
264 123 Controlled by highest temp of Zone
265 0 PWM always 0% (off)
266 -1 PWM always 100% (full on)
267 -2 Manual control (write to 'pwm#' to
268 ========== ===================================
269
270 The National LM85's have two vendor specific c
271 features. Tach. mode and Spinup Control. For m
272 see the LM85 datasheet or Application Note AN-
273 are not currently supported by the lm85 driver
274
275 The Analog Devices ADM1027 has several vendor
276 The number of pulses-per-rev of the fans can b
277 can be optimized for PWM operation, and an off
278 the temperatures to compensate for systemic er
279 measurements. These features are not currently
280 driver.
281
282 In addition to the ADM1027 features, the ADT74
283 Tmin control and THERM asserted counts. Automa
284 adjust the Tmin value to maintain the measured
285 specified temperature. There isn't much docume
286 the ADT7463 data sheet. This is not supported
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