1 Kernel driver lm90 1 Kernel driver lm90
2 ================== 2 ==================
3 3
4 Supported chips: 4 Supported chips:
5 5
6 * National Semiconductor LM84 <<
7 <<
8 Prefix: 'lm84' <<
9 <<
10 Addresses scanned: I2C 0x18 - 0x1a, 0x29 - <<
11 <<
12 Datasheet: Publicly available at the Natio <<
13 <<
14 * National Semiconductor LM90 6 * National Semiconductor LM90
15 7
16 Prefix: 'lm90' 8 Prefix: 'lm90'
17 9
18 Addresses scanned: I2C 0x4c 10 Addresses scanned: I2C 0x4c
19 11
20 Datasheet: Publicly available at the Natio 12 Datasheet: Publicly available at the National Semiconductor website
21 13
22 http://www.national.com/pf/LM/L 14 http://www.national.com/pf/LM/LM90.html
23 15
24 * National Semiconductor LM89 16 * National Semiconductor LM89
25 17
26 Prefix: 'lm89' (no auto-detection) 18 Prefix: 'lm89' (no auto-detection)
27 19
28 Addresses scanned: I2C 0x4c and 0x4d 20 Addresses scanned: I2C 0x4c and 0x4d
29 21
30 Datasheet: Publicly available at the Natio 22 Datasheet: Publicly available at the National Semiconductor website
31 23
32 http://www.national.com/mpf/LM/ 24 http://www.national.com/mpf/LM/LM89.html
33 25
34 * National Semiconductor LM99 26 * National Semiconductor LM99
35 27
36 Prefix: 'lm99' 28 Prefix: 'lm99'
37 29
38 Addresses scanned: I2C 0x4c and 0x4d 30 Addresses scanned: I2C 0x4c and 0x4d
39 31
40 Datasheet: Publicly available at the Natio 32 Datasheet: Publicly available at the National Semiconductor website
41 33
42 http://www.national.com/pf/LM/L 34 http://www.national.com/pf/LM/LM99.html
43 35
44 * National Semiconductor LM86 36 * National Semiconductor LM86
45 37
46 Prefix: 'lm86' 38 Prefix: 'lm86'
47 39
48 Addresses scanned: I2C 0x4c 40 Addresses scanned: I2C 0x4c
49 41
50 Datasheet: Publicly available at the Natio 42 Datasheet: Publicly available at the National Semiconductor website
51 43
52 http://www.national.com/mpf/LM/ 44 http://www.national.com/mpf/LM/LM86.html
53 45
54 * Analog Devices ADM1020 <<
55 <<
56 Prefix: 'adm1020' <<
57 <<
58 Addresses scanned: I2C 0x4c - 0x4e <<
59 <<
60 Datasheet: Publicly available at the Analo <<
61 <<
62 * Analog Devices ADM1021 <<
63 <<
64 Prefix: 'adm1021' <<
65 <<
66 Addresses scanned: I2C 0x18 - 0x1a, 0x29 - <<
67 <<
68 Datasheet: Publicly available at the Analo <<
69 <<
70 * Analog Devices ADM1021A/ADM1023 <<
71 <<
72 Prefix: 'adm1023' <<
73 <<
74 Addresses scanned: I2C 0x18 - 0x1a, 0x29 - <<
75 <<
76 Datasheet: Publicly available at the Analo <<
77 <<
78 * Analog Devices ADM1032 46 * Analog Devices ADM1032
79 47
80 Prefix: 'adm1032' 48 Prefix: 'adm1032'
81 49
82 Addresses scanned: I2C 0x4c and 0x4d 50 Addresses scanned: I2C 0x4c and 0x4d
83 51
84 Datasheet: Publicly available at the ON Se 52 Datasheet: Publicly available at the ON Semiconductor website
85 53
86 https://www.onsemi.com/PowerSol !! 54 http://www.onsemi.com/PowerSolutions/product.do?id=ADM1032
87 55
88 * Analog Devices ADT7461 56 * Analog Devices ADT7461
89 57
90 Prefix: 'adt7461' 58 Prefix: 'adt7461'
91 59
92 Addresses scanned: I2C 0x4c and 0x4d 60 Addresses scanned: I2C 0x4c and 0x4d
93 61
94 Datasheet: Publicly available at the ON Se 62 Datasheet: Publicly available at the ON Semiconductor website
95 63
96 https://www.onsemi.com/PowerSol !! 64 http://www.onsemi.com/PowerSolutions/product.do?id=ADT7461
97 65
98 * Analog Devices ADT7461A 66 * Analog Devices ADT7461A
99 67
100 Prefix: 'adt7461a' 68 Prefix: 'adt7461a'
101 69
102 Addresses scanned: I2C 0x4c and 0x4d 70 Addresses scanned: I2C 0x4c and 0x4d
103 71
104 Datasheet: Publicly available at the ON Se 72 Datasheet: Publicly available at the ON Semiconductor website
105 73
106 https://www.onsemi.com/PowerSol !! 74 http://www.onsemi.com/PowerSolutions/product.do?id=ADT7461A
107 <<
108 * Analog Devices ADT7481 <<
109 <<
110 Prefix: 'adt7481' <<
111 <<
112 Addresses scanned: I2C 0x4b and 0x4c <<
113 <<
114 Datasheet: Publicly available at the ON Se <<
115 <<
116 https://www.onsemi.com/PowerSol <<
117 <<
118 * Analog Devices ADT7482 <<
119 <<
120 Prefix: 'adt7482' <<
121 <<
122 Addresses scanned: I2C 0x4c <<
123 <<
124 Datasheet: Publicly available at the ON Se <<
125 <<
126 https://www.onsemi.com/PowerSol <<
127 <<
128 * Analog Devices ADT7483A <<
129 <<
130 Prefix: 'adt7483a' <<
131 <<
132 Addresses scanned: I2C 0x18, 0x19, 0x1a, 0 <<
133 <<
134 Datasheet: Publicly available at the ON Se <<
135 <<
136 https://www.onsemi.com/PowerSol <<
137 75
138 * ON Semiconductor NCT1008 76 * ON Semiconductor NCT1008
139 77
140 Prefix: 'nct1008' 78 Prefix: 'nct1008'
141 79
142 Addresses scanned: I2C 0x4c and 0x4d 80 Addresses scanned: I2C 0x4c and 0x4d
143 81
144 Datasheet: Publicly available at the ON Se 82 Datasheet: Publicly available at the ON Semiconductor website
145 83
146 https://www.onsemi.com/PowerSol !! 84 http://www.onsemi.com/PowerSolutions/product.do?id=NCT1008
147 <<
148 * ON Semiconductor NCT210 <<
149 <<
150 Prefix: 'adm1021' <<
151 <<
152 Addresses scanned: I2C 0x18 - 0x1a, 0x29 - <<
153 <<
154 Datasheet: Publicly available at the ON Se <<
155 <<
156 https://www.onsemi.com/PowerSol <<
157 <<
158 * ON Semiconductor NCT214 <<
159 <<
160 Prefix: 'nct214' <<
161 <<
162 Addresses scanned: I2C 0x18 - 0x1a, 0x29 - <<
163 <<
164 Datasheet: Publicly available at the ON Se <<
165 <<
166 https://www.onsemi.com/PowerSol <<
167 <<
168 * ON Semiconductor NCT218 <<
169 <<
170 Prefix: 'nct218' <<
171 <<
172 Addresses scanned: I2C 0x4c - 0x4d <<
173 <<
174 Datasheet: Publicly available at the ON Se <<
175 <<
176 https://www.onsemi.com/PowerSol <<
177 <<
178 * ON Semiconductor NCT72 <<
179 <<
180 Prefix: 'nct72' <<
181 <<
182 Addresses scanned: I2C 0x4c - 0x4d <<
183 <<
184 Datasheet: Publicly available at the ON Se <<
185 <<
186 https://www.onsemi.com/PowerSol <<
187 <<
188 * Maxim MAX1617 <<
189 <<
190 Prefix: 'max1617' <<
191 <<
192 Addresses scanned: I2C 0x18 - 0x1a, 0x29 - <<
193 <<
194 Datasheet: Publicly available at the Maxim <<
195 <<
196 * Maxim MAX1617A <<
197 <<
198 Prefix: 'max1617a' <<
199 <<
200 Addresses scanned: I2C 0x18 - 0x1a, 0x29 - <<
201 <<
202 Datasheet: Publicly available at the Maxim <<
203 <<
204 * Maxim MAX6642 <<
205 <<
206 Prefix: 'max6642' <<
207 <<
208 Addresses scanned: I2C 0x48-0x4f <<
209 <<
210 Datasheet: Publicly available at the Maxim <<
211 <<
212 http://datasheets.maxim-ic.com/ <<
213 85
214 * Maxim MAX6646 86 * Maxim MAX6646
215 87
216 Prefix: 'max6646' 88 Prefix: 'max6646'
217 89
218 Addresses scanned: I2C 0x4d 90 Addresses scanned: I2C 0x4d
219 91
220 Datasheet: Publicly available at the Maxim 92 Datasheet: Publicly available at the Maxim website
221 93
222 http://www.maxim-ic.com/quick_v 94 http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3497
223 95
224 * Maxim MAX6647 96 * Maxim MAX6647
225 97
226 Prefix: 'max6646' 98 Prefix: 'max6646'
227 99
228 Addresses scanned: I2C 0x4e 100 Addresses scanned: I2C 0x4e
229 101
230 Datasheet: Publicly available at the Maxim 102 Datasheet: Publicly available at the Maxim website
231 103
232 http://www.maxim-ic.com/quick_v 104 http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3497
233 105
234 * Maxim MAX6648 106 * Maxim MAX6648
235 107
236 Prefix: 'max6648' !! 108 Prefix: 'max6646'
237 109
238 Addresses scanned: I2C 0x4c 110 Addresses scanned: I2C 0x4c
239 111
240 Datasheet: Publicly available at the Maxim 112 Datasheet: Publicly available at the Maxim website
241 113
242 http://www.maxim-ic.com/quick_v 114 http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3500
243 115
244 * Maxim MAX6649 116 * Maxim MAX6649
245 117
246 Prefix: 'max6646' 118 Prefix: 'max6646'
247 119
248 Addresses scanned: I2C 0x4c 120 Addresses scanned: I2C 0x4c
249 121
250 Datasheet: Publicly available at the Maxim 122 Datasheet: Publicly available at the Maxim website
251 123
252 http://www.maxim-ic.com/quick_v 124 http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3497
253 125
254 * Maxim MAX6654 <<
255 <<
256 Prefix: 'max6654' <<
257 <<
258 Addresses scanned: I2C 0x18, 0x19, 0x1a, 0 <<
259 <<
260 0x4c, 0x4d and 0x4e <<
261 <<
262 Datasheet: Publicly available at the Maxim <<
263 <<
264 https://www.maximintegrated.com <<
265 <<
266 * Maxim MAX6657 126 * Maxim MAX6657
267 127
268 Prefix: 'max6657' 128 Prefix: 'max6657'
269 129
270 Addresses scanned: I2C 0x4c 130 Addresses scanned: I2C 0x4c
271 131
272 Datasheet: Publicly available at the Maxim 132 Datasheet: Publicly available at the Maxim website
273 133
274 http://www.maxim-ic.com/quick_v 134 http://www.maxim-ic.com/quick_view2.cfm/qv_pk/2578
275 135
276 * Maxim MAX6658 136 * Maxim MAX6658
277 137
278 Prefix: 'max6657' 138 Prefix: 'max6657'
279 139
280 Addresses scanned: I2C 0x4c 140 Addresses scanned: I2C 0x4c
281 141
282 Datasheet: Publicly available at the Maxim 142 Datasheet: Publicly available at the Maxim website
283 143
284 http://www.maxim-ic.com/quick_v 144 http://www.maxim-ic.com/quick_view2.cfm/qv_pk/2578
285 145
286 * Maxim MAX6659 146 * Maxim MAX6659
287 147
288 Prefix: 'max6659' 148 Prefix: 'max6659'
289 149
290 Addresses scanned: I2C 0x4c, 0x4d, 0x4e 150 Addresses scanned: I2C 0x4c, 0x4d, 0x4e
291 151
292 Datasheet: Publicly available at the Maxim 152 Datasheet: Publicly available at the Maxim website
293 153
294 http://www.maxim-ic.com/quick_v 154 http://www.maxim-ic.com/quick_view2.cfm/qv_pk/2578
295 155
296 * Maxim MAX6680 156 * Maxim MAX6680
297 157
298 Prefix: 'max6680' 158 Prefix: 'max6680'
299 159
300 Addresses scanned: I2C 0x18, 0x19, 0x1a, 0 160 Addresses scanned: I2C 0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b,
301 161
302 0x4c, 0x4d and 0x4e 162 0x4c, 0x4d and 0x4e
303 163
304 Datasheet: Publicly available at the Maxim 164 Datasheet: Publicly available at the Maxim website
305 165
306 http://www.maxim-ic.com/quick_v 166 http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3370
307 167
308 * Maxim MAX6681 168 * Maxim MAX6681
309 169
310 Prefix: 'max6680' 170 Prefix: 'max6680'
311 171
312 Addresses scanned: I2C 0x18, 0x19, 0x1a, 0 172 Addresses scanned: I2C 0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b,
313 173
314 0x4c, 0x4d and 0x4e 174 0x4c, 0x4d and 0x4e
315 175
316 Datasheet: Publicly available at the Maxim 176 Datasheet: Publicly available at the Maxim website
317 177
318 http://www.maxim-ic.com/quick_v 178 http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3370
319 179
320 * Maxim MAX6692 180 * Maxim MAX6692
321 181
322 Prefix: 'max6648' !! 182 Prefix: 'max6646'
323 183
324 Addresses scanned: I2C 0x4c 184 Addresses scanned: I2C 0x4c
325 185
326 Datasheet: Publicly available at the Maxim 186 Datasheet: Publicly available at the Maxim website
327 187
328 http://www.maxim-ic.com/quick_v 188 http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3500
329 189
330 * Maxim MAX6695 190 * Maxim MAX6695
331 191
332 Prefix: 'max6695' 192 Prefix: 'max6695'
333 193
334 Addresses scanned: I2C 0x18 194 Addresses scanned: I2C 0x18
335 195
336 Datasheet: Publicly available at the Maxim 196 Datasheet: Publicly available at the Maxim website
337 197
338 http://www.maxim-ic.com/datashe 198 http://www.maxim-ic.com/datasheet/index.mvp/id/4199
339 199
340 * Maxim MAX6696 200 * Maxim MAX6696
341 201
342 Prefix: 'max6695' 202 Prefix: 'max6695'
343 203
344 Addresses scanned: I2C 0x18, 0x19, 0x1a, 0 204 Addresses scanned: I2C 0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b,
345 205
346 0x4c, 0x4d and 0x4e 206 0x4c, 0x4d and 0x4e
347 207
348 Datasheet: Publicly available at the Maxim 208 Datasheet: Publicly available at the Maxim website
349 209
350 http://www.maxim-ic.com/datashe 210 http://www.maxim-ic.com/datasheet/index.mvp/id/4199
351 211
352 * Winbond/Nuvoton W83L771W/G 212 * Winbond/Nuvoton W83L771W/G
353 213
354 Prefix: 'w83l771' 214 Prefix: 'w83l771'
355 215
356 Addresses scanned: I2C 0x4c 216 Addresses scanned: I2C 0x4c
357 217
358 Datasheet: No longer available 218 Datasheet: No longer available
359 219
360 * Winbond/Nuvoton W83L771AWG/ASG 220 * Winbond/Nuvoton W83L771AWG/ASG
361 221
362 Prefix: 'w83l771' 222 Prefix: 'w83l771'
363 223
364 Addresses scanned: I2C 0x4c 224 Addresses scanned: I2C 0x4c
365 225
366 Datasheet: Not publicly available, can be 226 Datasheet: Not publicly available, can be requested from Nuvoton
367 227
368 * Philips/NXP SA56004X 228 * Philips/NXP SA56004X
369 229
370 Prefix: 'sa56004' 230 Prefix: 'sa56004'
371 231
372 Addresses scanned: I2C 0x48 through 0x4F 232 Addresses scanned: I2C 0x48 through 0x4F
373 233
374 Datasheet: Publicly available at NXP websi 234 Datasheet: Publicly available at NXP website
375 235
376 http://ics.nxp.com/products/int 236 http://ics.nxp.com/products/interface/datasheet/sa56004x.pdf
377 237
378 * GMT G781 238 * GMT G781
379 239
380 Prefix: 'g781' 240 Prefix: 'g781'
381 241
382 Addresses scanned: I2C 0x4c, 0x4d 242 Addresses scanned: I2C 0x4c, 0x4d
383 243
384 Datasheet: Not publicly available from GMT 244 Datasheet: Not publicly available from GMT
385 245
386 * Texas Instruments TMP451 246 * Texas Instruments TMP451
387 247
388 Prefix: 'tmp451' 248 Prefix: 'tmp451'
389 249
390 Addresses scanned: I2C 0x4c 250 Addresses scanned: I2C 0x4c
391 251
392 Datasheet: Publicly available at TI websit 252 Datasheet: Publicly available at TI website
393 253
394 https://www.ti.com/litv/pdf/sbo !! 254 http://www.ti.com/litv/pdf/sbos686
395 <<
396 * Texas Instruments TMP461 <<
397 <<
398 Prefix: 'tmp461' <<
399 <<
400 Addresses scanned: I2C 0x48 through 0x4F <<
401 <<
402 Datasheet: Publicly available at TI websit <<
403 <<
404 https://www.ti.com/lit/gpn/tmp4 <<
405 <<
406 * Philips NE1617, NE1617A <<
407 <<
408 Prefix: 'max1617' (probably detected as a <<
409 <<
410 Addresses scanned: I2C 0x18 - 0x1a, 0x29 - <<
411 <<
412 Datasheets: Publicly available at the Phil <<
413 <<
414 * Philips NE1618 <<
415 <<
416 Prefix: 'ne1618' <<
417 <<
418 Addresses scanned: I2C 0x18 - 0x1a, 0x29 - <<
419 <<
420 Datasheets: Publicly available at the Phil <<
421 <<
422 * Genesys Logic GL523SM <<
423 <<
424 Prefix: 'gl523sm' <<
425 <<
426 Addresses scanned: I2C 0x18 - 0x1a, 0x29 - <<
427 <<
428 Datasheet: <<
429 <<
430 * TI THMC10 <<
431 <<
432 Prefix: 'thmc10' <<
433 <<
434 Addresses scanned: I2C 0x18 - 0x1a, 0x29 - <<
435 <<
436 Datasheet: Publicly available at the TI we <<
437 <<
438 * Onsemi MC1066 <<
439 <<
440 Prefix: 'mc1066' <<
441 <<
442 Addresses scanned: I2C 0x18 - 0x1a, 0x29 - <<
443 <<
444 Datasheet: Publicly available at the Onsem <<
445 255
446 Author: Jean Delvare <jdelvare@suse.de> 256 Author: Jean Delvare <jdelvare@suse.de>
447 257
448 258
449 Description 259 Description
450 ----------- 260 -----------
451 261
452 The LM90 is a digital temperature sensor. It s 262 The LM90 is a digital temperature sensor. It senses its own temperature as
453 well as the temperature of up to one external 263 well as the temperature of up to one external diode. It is compatible
454 with many other devices, many of which are sup 264 with many other devices, many of which are supported by this driver.
455 265
456 The family of chips supported by this driver i <<
457 This chip as well as various compatible chips <<
458 temperature sensor with 8 bit accuracy. Later <<
459 and other additional features such as hysteres <<
460 registers. <<
461 <<
462 Note that there is no easy way to differentiat 266 Note that there is no easy way to differentiate between the MAX6657,
463 MAX6658 and MAX6659 variants. The extra featur 267 MAX6658 and MAX6659 variants. The extra features of the MAX6659 are only
464 supported by this driver if the chip is locate 268 supported by this driver if the chip is located at address 0x4d or 0x4e,
465 or if the chip type is explicitly selected as 269 or if the chip type is explicitly selected as max6659.
466 The MAX6680 and MAX6681 only differ in their p 270 The MAX6680 and MAX6681 only differ in their pinout, therefore they obviously
467 can't (and don't need to) be distinguished. 271 can't (and don't need to) be distinguished.
468 272
>> 273 The specificity of this family of chipsets over the ADM1021/LM84
>> 274 family is that it features critical limits with hysteresis, and an
>> 275 increased resolution of the remote temperature measurement.
>> 276
469 The different chipsets of the family are not s 277 The different chipsets of the family are not strictly identical, although
470 very similar. For reference, here comes a non- 278 very similar. For reference, here comes a non-exhaustive list of specific
471 features: 279 features:
472 280
473 LM84: <<
474 * 8 bit sensor resolution <<
475 <<
476 ADM1020, ADM1021, GL523SM, MAX1617, NE1617, NE <<
477 * 8 bit sensor resolution <<
478 * Low temperature limits <<
479 <<
480 NCT210, NE1618: <<
481 * 11 bit sensor resolution for remote temper <<
482 * Low temperature limits <<
483 <<
484 ADM1021A, ADM1023: <<
485 * Temperature offset register for remote tem <<
486 * 11 bit resolution for remote temperature s <<
487 * Low temperature limits <<
488 <<
489 LM90: 281 LM90:
490 * 11 bit resolution for remote temperature s <<
491 * Temperature offset register for remote tem <<
492 * Low and critical temperature limits <<
493 * Configurable conversion rate <<
494 * Filter and alert configuration register at 282 * Filter and alert configuration register at 0xBF.
495 * ALERT is triggered by temperatures over cr 283 * ALERT is triggered by temperatures over critical limits.
496 284
497 LM86 and LM89: 285 LM86 and LM89:
498 * Same as LM90 286 * Same as LM90
499 * Better external channel accuracy 287 * Better external channel accuracy
500 288
501 LM99: 289 LM99:
502 * Same as LM89 290 * Same as LM89
503 * External temperature shifted by 16 degrees 291 * External temperature shifted by 16 degrees down
504 292
505 ADM1032: 293 ADM1032:
506 * Consecutive alert register at 0x22. 294 * Consecutive alert register at 0x22.
507 * Conversion averaging. 295 * Conversion averaging.
508 * Up to 64 conversions/s. 296 * Up to 64 conversions/s.
509 * ALERT is triggered by open remote sensor. 297 * ALERT is triggered by open remote sensor.
510 * SMBus PEC support for Write Byte and Recei 298 * SMBus PEC support for Write Byte and Receive Byte transactions.
511 299
512 ADT7461, ADT7461A, NCT1008: 300 ADT7461, ADT7461A, NCT1008:
513 * Extended temperature range (breaks compati 301 * Extended temperature range (breaks compatibility)
514 * Lower resolution for remote temperature 302 * Lower resolution for remote temperature
515 * SMBus PEC support for Write Byte and Recei <<
516 * 10 bit temperature resolution <<
517 <<
518 ADT7481, ADT7482, ADT7483: <<
519 * Temperature offset register <<
520 * SMBus PEC support <<
521 * 10 bit temperature resolution for external <<
522 * Two remote sensors <<
523 * Selectable address (ADT7483) <<
524 <<
525 MAX6642: <<
526 * No critical limit register <<
527 * Conversion rate not configurable <<
528 * Better local resolution (10 bit) <<
529 * 10 bit external sensor resolution <<
530 <<
531 MAX6646, MAX6647, MAX6649: <<
532 * Better local resolution <<
533 * Extended range unsigned external temperatu <<
534 <<
535 MAX6648, MAX6692: <<
536 * Better local resolution <<
537 * Unsigned temperature <<
538 <<
539 MAX6654, MAX6690: <<
540 * Better local resolution <<
541 * Selectable address <<
542 * Remote sensor type selection <<
543 * Extended temperature range <<
544 * Extended resolution only available when co <<
545 303
546 MAX6657 and MAX6658: 304 MAX6657 and MAX6658:
547 * Better local resolution 305 * Better local resolution
548 * Remote sensor type selection 306 * Remote sensor type selection
549 307
550 MAX6659: 308 MAX6659:
551 * Better local resolution 309 * Better local resolution
552 * Selectable address 310 * Selectable address
553 * Second critical temperature limit 311 * Second critical temperature limit
554 * Remote sensor type selection 312 * Remote sensor type selection
555 313
556 MAX6680 and MAX6681: 314 MAX6680 and MAX6681:
557 * Selectable address 315 * Selectable address
558 * Remote sensor type selection 316 * Remote sensor type selection
559 317
560 MAX6695 and MAX6696: 318 MAX6695 and MAX6696:
561 * Better local resolution 319 * Better local resolution
562 * Selectable address (max6696) 320 * Selectable address (max6696)
563 * Second critical temperature limit 321 * Second critical temperature limit
564 * Two remote sensors 322 * Two remote sensors
565 323
566 W83L771W/G 324 W83L771W/G
567 * The G variant is lead-free, otherwise simi 325 * The G variant is lead-free, otherwise similar to the W.
568 * Filter and alert configuration register at 326 * Filter and alert configuration register at 0xBF
569 * Moving average (depending on conversion ra 327 * Moving average (depending on conversion rate)
570 328
571 W83L771AWG/ASG 329 W83L771AWG/ASG
572 * Successor of the W83L771W/G, same features 330 * Successor of the W83L771W/G, same features.
573 * The AWG and ASG variants only differ in pa 331 * The AWG and ASG variants only differ in package format.
574 * Diode ideality factor configuration (remot 332 * Diode ideality factor configuration (remote sensor) at 0xE3
575 333
576 SA56004X: 334 SA56004X:
577 * Better local resolution 335 * Better local resolution
578 336
579 All temperature values are given in degrees Ce 337 All temperature values are given in degrees Celsius. Resolution
580 is 1.0 degree for the local temperature, 0.125 338 is 1.0 degree for the local temperature, 0.125 degree for the remote
581 temperature, except for the MAX6654, MAX6657, !! 339 temperature, except for the MAX6657, MAX6658 and MAX6659 which have a
582 a resolution of 0.125 degree for both temperat !! 340 resolution of 0.125 degree for both temperatures.
583 341
584 Each sensor has its own high and low limits, p 342 Each sensor has its own high and low limits, plus a critical limit.
585 Additionally, there is a relative hysteresis v 343 Additionally, there is a relative hysteresis value common to both critical
586 values. To make life easier to user-space appl 344 values. To make life easier to user-space applications, two absolute values
587 are exported, one for each channel, but these 345 are exported, one for each channel, but these values are of course linked.
588 Only the local hysteresis can be set from user 346 Only the local hysteresis can be set from user-space, and the same delta
589 applies to the remote hysteresis. 347 applies to the remote hysteresis.
590 348
591 The lm90 driver will not update its values mor 349 The lm90 driver will not update its values more frequently than configured with
592 the update_interval attribute; reading them mo 350 the update_interval attribute; reading them more often will do no harm, but will
593 return 'old' values. 351 return 'old' values.
594 352
595 SMBus Alert Support 353 SMBus Alert Support
596 ------------------- 354 -------------------
597 355
598 This driver has basic support for SMBus alert. 356 This driver has basic support for SMBus alert. When an alert is received,
599 the status register is read and the faulty tem 357 the status register is read and the faulty temperature channel is logged.
600 358
601 The Analog Devices chips (ADM1032, ADT7461 and 359 The Analog Devices chips (ADM1032, ADT7461 and ADT7461A) and ON
602 Semiconductor chips (NCT1008) do not implement 360 Semiconductor chips (NCT1008) do not implement the SMBus alert protocol
603 properly so additional care is needed: the ALE 361 properly so additional care is needed: the ALERT output is disabled when
604 an alert is received, and is re-enabled only w 362 an alert is received, and is re-enabled only when the alarm is gone.
605 Otherwise the chip would block alerts from oth 363 Otherwise the chip would block alerts from other chips in the bus as long
606 as the alarm is active. 364 as the alarm is active.
607 365
608 PEC Support 366 PEC Support
609 ----------- 367 -----------
610 368
611 The ADM1032 is the only chip of the family whi 369 The ADM1032 is the only chip of the family which supports PEC. It does
612 not support PEC on all transactions though, so 370 not support PEC on all transactions though, so some care must be taken.
613 371
614 When reading a register value, the PEC byte is 372 When reading a register value, the PEC byte is computed and sent by the
615 ADM1032 chip. However, in the case of a combin 373 ADM1032 chip. However, in the case of a combined transaction (SMBus Read
616 Byte), the ADM1032 computes the CRC value over 374 Byte), the ADM1032 computes the CRC value over only the second half of
617 the message rather than its entirety, because 375 the message rather than its entirety, because it thinks the first half
618 of the message belongs to a different transact 376 of the message belongs to a different transaction. As a result, the CRC
619 value differs from what the SMBus master expec 377 value differs from what the SMBus master expects, and all reads fail.
620 378
621 For this reason, the lm90 driver will enable P 379 For this reason, the lm90 driver will enable PEC for the ADM1032 only if
622 the bus supports the SMBus Send Byte and Recei 380 the bus supports the SMBus Send Byte and Receive Byte transaction types.
623 These transactions will be used to read regist 381 These transactions will be used to read register values, instead of
624 SMBus Read Byte, and PEC will work properly. 382 SMBus Read Byte, and PEC will work properly.
625 383
626 Additionally, the ADM1032 doesn't support SMBu 384 Additionally, the ADM1032 doesn't support SMBus Send Byte with PEC.
627 Instead, it will try to write the PEC value to 385 Instead, it will try to write the PEC value to the register (because the
628 SMBus Send Byte transaction with PEC is simila 386 SMBus Send Byte transaction with PEC is similar to a Write Byte transaction
629 without PEC), which is not what we want. Thus, 387 without PEC), which is not what we want. Thus, PEC is explicitly disabled
630 on SMBus Send Byte transactions in the lm90 dr 388 on SMBus Send Byte transactions in the lm90 driver.
631 389
632 PEC on byte data transactions represents a sig 390 PEC on byte data transactions represents a significant increase in bandwidth
633 usage (+33% for writes, +25% for reads) in nor 391 usage (+33% for writes, +25% for reads) in normal conditions. With the need
634 to use two SMBus transaction for reads, this o 392 to use two SMBus transaction for reads, this overhead jumps to +50%. Worse,
635 two transactions will typically mean twice as 393 two transactions will typically mean twice as much delay waiting for
636 transaction completion, effectively doubling t 394 transaction completion, effectively doubling the register cache refresh time.
637 I guess reliability comes at a price, but it's 395 I guess reliability comes at a price, but it's quite expensive this time.
638 396
639 So, as not everyone might enjoy the slowdown, !! 397 So, as not everyone might enjoy the slowdown, PEC can be disabled through
640 can be enabled through sysfs. Just write 1 to !! 398 sysfs. Just write 0 to the "pec" file and PEC will be disabled. Write 1
641 enabled. Write 0 to that file to disable PEC a !! 399 to that file to enable PEC again.
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