xref: /linux/Documentation/hwmon/ltc2978.rst (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1.. SPDX-License-Identifier: GPL-2.0
2
3Kernel driver ltc2978
4=====================
5
6Supported chips:
7
8  * Linear Technology LTC2972
9
10    Prefix: 'ltc2972'
11
12    Addresses scanned: -
13
14    Datasheet: https://www.analog.com/en/products/ltc2972.html
15
16  * Linear Technology LTC2974
17
18    Prefix: 'ltc2974'
19
20    Addresses scanned: -
21
22    Datasheet: https://www.analog.com/en/products/ltc2974
23
24  * Linear Technology LTC2975
25
26    Prefix: 'ltc2975'
27
28    Addresses scanned: -
29
30    Datasheet: https://www.analog.com/en/products/ltc2975
31
32  * Linear Technology LTC2977
33
34    Prefix: 'ltc2977'
35
36    Addresses scanned: -
37
38    Datasheet: https://www.analog.com/en/products/ltc2977
39
40  * Linear Technology LTC2978, LTC2978A
41
42    Prefix: 'ltc2978'
43
44    Addresses scanned: -
45
46    Datasheet: https://www.analog.com/en/products/ltc2978
47
48	       https://www.analog.com/en/products/ltc2978a
49
50  * Linear Technology LTC2979
51
52    Prefix: 'ltc2979'
53
54    Addresses scanned: -
55
56    Datasheet: https://www.analog.com/en/products/ltc2979
57
58  * Linear Technology LTC2980
59
60    Prefix: 'ltc2980'
61
62    Addresses scanned: -
63
64    Datasheet: https://www.analog.com/en/products/ltc2980
65
66  * Linear Technology LTC3880
67
68    Prefix: 'ltc3880'
69
70    Addresses scanned: -
71
72    Datasheet: https://www.analog.com/en/products/ltc3880
73
74  * Linear Technology LTC3882
75
76    Prefix: 'ltc3882'
77
78    Addresses scanned: -
79
80    Datasheet: https://www.analog.com/en/products/ltc3882
81
82  * Linear Technology LTC3883
83
84    Prefix: 'ltc3883'
85
86    Addresses scanned: -
87
88    Datasheet: https://www.analog.com/en/products/ltc3883
89
90  * Linear Technology LTC3884
91
92    Prefix: 'ltc3884'
93
94    Addresses scanned: -
95
96    Datasheet: https://www.analog.com/en/products/ltc3884
97
98  * Linear Technology LTC3886
99
100    Prefix: 'ltc3886'
101
102    Addresses scanned: -
103
104    Datasheet: https://www.analog.com/en/products/ltc3886
105
106  * Linear Technology LTC3887
107
108    Prefix: 'ltc3887'
109
110    Addresses scanned: -
111
112    Datasheet: https://www.analog.com/en/products/ltc3887
113
114  * Linear Technology LTC3889
115
116    Prefix: 'ltc3889'
117
118    Addresses scanned: -
119
120    Datasheet: https://www.analog.com/en/products/ltc3889
121
122  * Linear Technology LTC7841
123
124    Prefix: 'ltc7841'
125
126    Addresses scanned: -
127
128    Datasheet: https://www.analog.com/en/products/ltc7841
129
130  * Linear Technology LTC7880
131
132    Prefix: 'ltc7880'
133
134    Addresses scanned: -
135
136    Datasheet: https://www.analog.com/en/products/ltc7880
137
138  * Linear Technology LTM2987
139
140    Prefix: 'ltm2987'
141
142    Addresses scanned: -
143
144    Datasheet: https://www.analog.com/en/products/ltm2987
145
146  * Linear Technology LTM4644
147
148    Prefix: 'ltm4644'
149
150    Addresses scanned: -
151
152    Datasheet: https://www.analog.com/en/products/ltm4644
153
154   * Linear Technology LTM4675
155
156    Prefix: 'ltm4675'
157
158    Addresses scanned: -
159
160    Datasheet: https://www.analog.com/en/products/ltm4675
161
162  * Linear Technology LTM4676
163
164    Prefix: 'ltm4676'
165
166    Addresses scanned: -
167
168    Datasheet: https://www.analog.com/en/products/ltm4676
169
170  * Linear Technology LTM4677
171
172    Prefix: 'ltm4677'
173
174    Addresses scanned: -
175
176    Datasheet: https://www.analog.com/en/products/ltm4677
177
178  * Linear Technology LTM4678
179
180    Prefix: 'ltm4678'
181
182    Addresses scanned: -
183
184    Datasheet: https://www.analog.com/en/products/ltm4678
185
186  * Analog Devices LTM4680
187
188    Prefix: 'ltm4680'
189
190    Addresses scanned: -
191
192    Datasheet: https://www.analog.com/ltm4680
193
194  * Analog Devices LTM4686
195
196    Prefix: 'ltm4686'
197
198    Addresses scanned: -
199
200    Datasheet: https://www.analog.com/ltm4686
201
202  * Analog Devices LTM4700
203
204    Prefix: 'ltm4700'
205
206    Addresses scanned: -
207
208    Datasheet: https://www.analog.com/ltm4700
209
210
211
212Author: Guenter Roeck <linux@roeck-us.net>
213
214
215Description
216-----------
217
218- LTC2974 and LTC2975 are quad digital power supply managers.
219- LTC2978 is an octal power supply monitor.
220- LTC2977 is a pin compatible replacement for LTC2978.
221- LTC2980 is a 16-channel Power System Manager, consisting of two LTC2977
222- in a single die. The chip is instantiated and reported as two separate chips
223- on two different I2C bus addresses.
224- LTC3880, LTC3882, LTC3886, and LTC3887 are dual output poly-phase step-down
225- DC/DC controllers.
226- LTC3883 is a single phase step-down DC/DC controller.
227- LTM2987 is a 16-channel Power System Manager with two LTC2977 plus
228- additional components on a single die. The chip is instantiated and reported
229- as two separate chips on two different I2C bus addresses.
230- LTM4675 is a dual 9A or single 18A μModule regulator
231- LTM4676 is a dual 13A or single 26A uModule regulator.
232- LTM4686 is a dual 10A or single 20A uModule regulator.
233
234
235Usage Notes
236-----------
237
238This driver does not probe for PMBus devices. You will have to instantiate
239devices explicitly.
240
241Example: the following commands will load the driver for an LTC2978 at address
2420x60 on I2C bus #1::
243
244	# modprobe ltc2978
245	# echo ltc2978 0x60 > /sys/bus/i2c/devices/i2c-1/new_device
246
247
248Sysfs attributes
249----------------
250
251======================= ========================================================
252in1_label		"vin"
253
254in1_input		Measured input voltage.
255
256in1_min			Minimum input voltage.
257
258in1_max			Maximum input voltage.
259
260			LTC2974, LTC2975, LTC2977, LTC2980, LTC2978,
261			LTC2979 and LTM2987 only.
262
263in1_lcrit		Critical minimum input voltage.
264
265			LTC2972, LTC2974, LTC2975, LTC2977, LTC2980, LTC2978,
266			LTC2979 and LTM2987 only.
267
268in1_crit		Critical maximum input voltage.
269
270in1_min_alarm		Input voltage low alarm.
271
272in1_max_alarm		Input voltage high alarm.
273
274			LTC2972, LTC2974, LTC2975, LTC2977, LTC2980, LTC2978,
275			LTC2979 and LTM2987 only.
276
277in1_lcrit_alarm		Input voltage critical low alarm.
278
279			LTC2972, LTC2974, LTC2975, LTC2977, LTC2980, LTC2978,
280			LTC2979 and LTM2987 only.
281
282in1_crit_alarm		Input voltage critical high alarm.
283
284in1_lowest		Lowest input voltage.
285
286			LTC2972, LTC2974, LTC2975, LTC2977, LTC2980, LTC2978,
287			and LTM2987 only.
288
289in1_highest		Highest input voltage.
290
291in1_reset_history	Reset input voltage history.
292
293in[N]_label		"vout[1-8]".
294
295			- LTC2972: N=2-3
296			- LTC2974, LTC2975: N=2-5
297			- LTC2977, LTC2979, LTC2980, LTM2987: N=2-9
298			- LTC2978: N=2-9
299			- LTC3880, LTC3882, LTC3884, LTC23886 LTC3887, LTC3889,
300			  LTC7880, LTM4644, LTM4675, LTM4676, LTM4677, LTM4678,
301			  LTM4680, LTM4700: N=2-3
302			- LTC3883: N=2
303			- LTC7841: N=2
304
305in[N]_input		Measured output voltage.
306
307in[N]_min		Minimum output voltage.
308
309in[N]_max		Maximum output voltage.
310
311in[N]_lcrit		Critical minimum output voltage.
312
313in[N]_crit		Critical maximum output voltage.
314
315in[N]_min_alarm		Output voltage low alarm.
316
317in[N]_max_alarm		Output voltage high alarm.
318
319in[N]_lcrit_alarm	Output voltage critical low alarm.
320
321in[N]_crit_alarm	Output voltage critical high alarm.
322
323in[N]_lowest		Lowest output voltage.
324
325			LTC2972, LTC2974, LTC2975,and LTC2978 only.
326
327in[N]_highest		Highest output voltage.
328
329in[N]_reset_history	Reset output voltage history.
330
331temp[N]_input		Measured temperature.
332
333			- On LTC2972, temp[1-2] report external temperatures,
334			  and temp 3 reports the chip temperature.
335			- On LTC2974 and LTC2975, temp[1-4] report external
336			  temperatures, and temp5 reports the chip temperature.
337			- On LTC2977, LTC2979, LTC2980, LTC2978, and LTM2987,
338			  only one temperature measurement is supported and
339			  reports the chip temperature.
340			- On LTC3880, LTC3882, LTC3886, LTC3887, LTC3889,
341			  LTM4664, LTM4675, LTM4676, LTM4677, LTM4678, LTM4680,
342			  and LTM4700, temp1 and temp2 report external
343			  temperatures, and temp3 reports the chip temperature.
344			- On LTC3883, temp1 reports an external temperature,
345			  and temp2 reports the chip temperature.
346
347temp[N]_min		Minimum temperature.
348
349			LTC2972, LTC2974, LCT2977, LTM2980, LTC2978,
350			LTC2979, and LTM2987 only.
351
352temp[N]_max		Maximum temperature.
353
354temp[N]_lcrit		Critical low temperature.
355
356temp[N]_crit		Critical high temperature.
357
358temp[N]_min_alarm	Temperature low alarm.
359
360			LTC2972, LTC2974, LTC2975, LTC2977, LTM2980, LTC2978,
361			LTC2979, and LTM2987 only.
362
363temp[N]_max_alarm	Temperature high alarm.
364
365
366temp[N]_lcrit_alarm	Temperature critical low alarm.
367
368temp[N]_crit_alarm	Temperature critical high alarm.
369
370temp[N]_lowest		Lowest measured temperature.
371
372			- LTC2972, LTC2974, LTC2975, LTC2977, LTM2980, LTC2978,
373			  LTC2979, and LTM2987 only.
374			- Not supported for chip temperature sensor on LTC2974
375			  and LTC2975.
376
377temp[N]_highest		Highest measured temperature.
378
379			Not supported for chip temperature sensor on
380			LTC2974 and LTC2975.
381
382temp[N]_reset_history	Reset temperature history.
383
384			Not supported for chip temperature sensor on
385			LTC2974 and LTC2975.
386
387power1_label		"pin". LTC3883 and LTC3886 only.
388
389power1_input		Measured input power.
390
391power[N]_label		"pout[1-4]".
392
393			- LTC2972: N=1-2
394			- LTC2974, LTC2975: N=1-4
395			- LTC2977, LTC2979, LTC2980, LTM2987: Not supported
396			- LTC2978: Not supported
397			- LTC3880, LTC3882, LTC3884, LTC3886, LTC3887, LTC3889,
398			  LTM4664, LTM4675, LTM4676, LTM4677, LTM4678, LTM4680,
399			  LTM4700: N=1-2
400			- LTC3883: N=2
401
402power[N]_input		Measured output power.
403
404curr1_label		"iin".
405
406			LTC3880, LTC3883, LTC3884, LTC3886, LTC3887, LTC3889,
407			LTM4644, LTM4675, LTM4676, LTM4677, LTM4678, LTM4680,
408			and LTM4700 only.
409
410curr1_input		Measured input current.
411
412curr1_max		Maximum input current.
413
414curr1_max_alarm		Input current high alarm.
415
416curr1_highest		Highest input current.
417
418			LTC3883 and LTC3886 only.
419
420curr1_reset_history	Reset input current history.
421
422			LTC3883 and LTC3886 only.
423
424curr[N]_label		"iout[1-4]".
425
426			- LTC2972: N-1-2
427			- LTC2974, LTC2975: N=1-4
428			- LTC2977, LTC2979, LTC2980, LTM2987: not supported
429			- LTC2978: not supported
430			- LTC3880, LTC3882, LTC3884, LTC3886, LTC3887, LTC3889,
431			  LTM4664, LTM4675, LTM4676, LTM4677, LTM4678, LTM4680,
432			  LTM4700: N=2-3
433			- LTC3883: N=2
434			- LTC7841: N=2
435
436curr[N]_input		Measured output current.
437
438curr[N]_max		Maximum output current.
439
440curr[N]_crit		Critical high output current.
441
442curr[N]_lcrit		Critical low output current.
443
444			LTC2972, LTC2974 and LTC2975 only.
445
446curr[N]_max_alarm	Output current high alarm.
447
448curr[N]_crit_alarm	Output current critical high alarm.
449
450curr[N]_lcrit_alarm	Output current critical low alarm.
451
452			LTC2972, LTC2974 and LTC2975 only.
453
454curr[N]_lowest		Lowest output current.
455
456			LTC2972, LTC2974 and LTC2975 only.
457
458curr[N]_highest		Highest output current.
459
460curr[N]_reset_history	Reset output current history.
461======================= ========================================================
462