Documentation/hwmon/ltc2978.rst

   1 .. SPDX-License-Identifier: GPL-2.0
   2
   3 Kernel driver ltc2978
   4 =====================
   5
   6 Supported 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
 212 Author: Guenter Roeck <linux@roeck-us.net>
 213
 214
 215 Description
 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
 235 Usage Notes
 236 -----------
 237
 238 This driver does not probe for PMBus devices. You will have to instantiate
 239 devices explicitly.
 240
 241 Example: the following commands will load the driver for an LTC2978 at address
 242 0x60 on I2C bus #1::
 243
 244         # modprobe ltc2978
 245         # echo ltc2978 0x60 > /sys/bus/i2c/devices/i2c-1/new_device
 246
 247
 248 Sysfs attributes
 249 ----------------
 250
 251 ======================= ========================================================
 252 in1_label               "vin"
 253
 254 in1_input               Measured input voltage.
 255
 256 in1_min                 Minimum input voltage.
 257
 258 in1_max                 Maximum input voltage.
 259
 260                         LTC2974, LTC2975, LTC2977, LTC2980, LTC2978,
 261                         LTC2979 and LTM2987 only.
 262
 263 in1_lcrit               Critical minimum input voltage.
 264
 265                         LTC2972, LTC2974, LTC2975, LTC2977, LTC2980, LTC2978,
 266                         LTC2979 and LTM2987 only.
 267
 268 in1_crit                Critical maximum input voltage.
 269
 270 in1_min_alarm           Input voltage low alarm.
 271
 272 in1_max_alarm           Input voltage high alarm.
 273
 274                         LTC2972, LTC2974, LTC2975, LTC2977, LTC2980, LTC2978,
 275                         LTC2979 and LTM2987 only.
 276
 277 in1_lcrit_alarm         Input voltage critical low alarm.
 278
 279                         LTC2972, LTC2974, LTC2975, LTC2977, LTC2980, LTC2978,
 280                         LTC2979 and LTM2987 only.
 281
 282 in1_crit_alarm          Input voltage critical high alarm.
 283
 284 in1_lowest              Lowest input voltage.
 285
 286                         LTC2972, LTC2974, LTC2975, LTC2977, LTC2980, LTC2978,
 287                         and LTM2987 only.
 288
 289 in1_highest             Highest input voltage.
 290
 291 in1_reset_history       Reset input voltage history.
 292
 293 in[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
 305 in[N]_input             Measured output voltage.
 306
 307 in[N]_min               Minimum output voltage.
 308
 309 in[N]_max               Maximum output voltage.
 310
 311 in[N]_lcrit             Critical minimum output voltage.
 312
 313 in[N]_crit              Critical maximum output voltage.
 314
 315 in[N]_min_alarm         Output voltage low alarm.
 316
 317 in[N]_max_alarm         Output voltage high alarm.
 318
 319 in[N]_lcrit_alarm       Output voltage critical low alarm.
 320
 321 in[N]_crit_alarm        Output voltage critical high alarm.
 322
 323 in[N]_lowest            Lowest output voltage.
 324
 325                         LTC2972, LTC2974, LTC2975,and LTC2978 only.
 326
 327 in[N]_highest           Highest output voltage.
 328
 329 in[N]_reset_history     Reset output voltage history.
 330
 331 temp[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
 347 temp[N]_min             Minimum temperature.
 348
 349                         LTC2972, LTC2974, LCT2977, LTM2980, LTC2978,
 350                         LTC2979, and LTM2987 only.
 351
 352 temp[N]_max             Maximum temperature.
 353
 354 temp[N]_lcrit           Critical low temperature.
 355
 356 temp[N]_crit            Critical high temperature.
 357
 358 temp[N]_min_alarm       Temperature low alarm.
 359
 360                         LTC2972, LTC2974, LTC2975, LTC2977, LTM2980, LTC2978,
 361                         LTC2979, and LTM2987 only.
 362
 363 temp[N]_max_alarm       Temperature high alarm.
 364
 365
 366 temp[N]_lcrit_alarm     Temperature critical low alarm.
 367
 368 temp[N]_crit_alarm      Temperature critical high alarm.
 369
 370 temp[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
 377 temp[N]_highest         Highest measured temperature.
 378
 379                         Not supported for chip temperature sensor on
 380                         LTC2974 and LTC2975.
 381
 382 temp[N]_reset_history   Reset temperature history.
 383
 384                         Not supported for chip temperature sensor on
 385                         LTC2974 and LTC2975.
 386
 387 power1_label            "pin". LTC3883 and LTC3886 only.
 388
 389 power1_input            Measured input power.
 390
 391 power[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
 402 power[N]_input          Measured output power.
 403
 404 curr1_label             "iin".
 405
 406                         LTC3880, LTC3883, LTC3884, LTC3886, LTC3887, LTC3889,
 407                         LTM4644, LTM4675, LTM4676, LTM4677, LTM4678, LTM4680,
 408                         and LTM4700 only.
 409
 410 curr1_input             Measured input current.
 411
 412 curr1_max               Maximum input current.
 413
 414 curr1_max_alarm         Input current high alarm.
 415
 416 curr1_highest           Highest input current.
 417
 418                         LTC3883 and LTC3886 only.
 419
 420 curr1_reset_history     Reset input current history.
 421
 422                         LTC3883 and LTC3886 only.
 423
 424 curr[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
 436 curr[N]_input           Measured output current.
 437
 438 curr[N]_max             Maximum output current.
 439
 440 curr[N]_crit            Critical high output current.
 441
 442 curr[N]_lcrit           Critical low output current.
 443
 444                         LTC2972, LTC2974 and LTC2975 only.
 445
 446 curr[N]_max_alarm       Output current high alarm.
 447
 448 curr[N]_crit_alarm      Output current critical high alarm.
 449
 450 curr[N]_lcrit_alarm     Output current critical low alarm.
 451
 452                         LTC2972, LTC2974 and LTC2975 only.
 453
 454 curr[N]_lowest          Lowest output current.
 455
 456                         LTC2972, LTC2974 and LTC2975 only.
 457
 458 curr[N]_highest         Highest output current.
 459
 460 curr[N]_reset_history   Reset output current history.
 461 ======================= ========================================================