Documentation/hwmon/ltc2978.rst

   1 Kernel driver ltc2978
   2 =====================
   3
   4 Supported chips:
   5
   6   * Linear Technology LTC2974
   7
   8     Prefix: 'ltc2974'
   9
  10     Addresses scanned: -
  11
  12     Datasheet: http://www.linear.com/product/ltc2974
  13
  14   * Linear Technology LTC2975
  15
  16     Prefix: 'ltc2975'
  17
  18     Addresses scanned: -
  19
  20     Datasheet: http://www.linear.com/product/ltc2975
  21
  22   * Linear Technology LTC2977
  23
  24     Prefix: 'ltc2977'
  25
  26     Addresses scanned: -
  27
  28     Datasheet: http://www.linear.com/product/ltc2977
  29
  30   * Linear Technology LTC2978, LTC2978A
  31
  32     Prefix: 'ltc2978'
  33
  34     Addresses scanned: -
  35
  36     Datasheet: http://www.linear.com/product/ltc2978
  37
  38                http://www.linear.com/product/ltc2978a
  39
  40   * Linear Technology LTC2980
  41
  42     Prefix: 'ltc2980'
  43
  44     Addresses scanned: -
  45
  46     Datasheet: http://www.linear.com/product/ltc2980
  47
  48   * Linear Technology LTC3880
  49
  50     Prefix: 'ltc3880'
  51
  52     Addresses scanned: -
  53
  54     Datasheet: http://www.linear.com/product/ltc3880
  55
  56   * Linear Technology LTC3882
  57
  58     Prefix: 'ltc3882'
  59
  60     Addresses scanned: -
  61
  62     Datasheet: http://www.linear.com/product/ltc3882
  63
  64   * Linear Technology LTC3883
  65
  66     Prefix: 'ltc3883'
  67
  68     Addresses scanned: -
  69
  70     Datasheet: http://www.linear.com/product/ltc3883
  71
  72   * Linear Technology LTC3886
  73
  74     Prefix: 'ltc3886'
  75
  76     Addresses scanned: -
  77
  78     Datasheet: http://www.linear.com/product/ltc3886
  79
  80   * Linear Technology LTC3887
  81
  82     Prefix: 'ltc3887'
  83
  84     Addresses scanned: -
  85
  86     Datasheet: http://www.linear.com/product/ltc3887
  87
  88   * Linear Technology LTM2987
  89
  90     Prefix: 'ltm2987'
  91
  92     Addresses scanned: -
  93
  94     Datasheet: http://www.linear.com/product/ltm2987
  95
  96   * Linear Technology LTM4675
  97
  98     Prefix: 'ltm4675'
  99
 100     Addresses scanned: -
 101
 102     Datasheet: http://www.linear.com/product/ltm4675
 103
 104   * Linear Technology LTM4676
 105
 106     Prefix: 'ltm4676'
 107
 108     Addresses scanned: -
 109
 110     Datasheet: http://www.linear.com/product/ltm4676
 111
 112   * Analog Devices LTM4686
 113
 114     Prefix: 'ltm4686'
 115
 116     Addresses scanned: -
 117
 118     Datasheet: http://www.analog.com/ltm4686
 119
 120
 121 Author: Guenter Roeck <linux@roeck-us.net>
 122
 123
 124 Description
 125 -----------
 126
 127 - LTC2974 and LTC2975 are quad digital power supply managers.
 128 - LTC2978 is an octal power supply monitor.
 129 - LTC2977 is a pin compatible replacement for LTC2978.
 130 - LTC2980 is a 16-channel Power System Manager, consisting of two LTC2977
 131 - in a single die. The chip is instantiated and reported as two separate chips
 132 - on two different I2C bus addresses.
 133 - LTC3880, LTC3882, LTC3886, and LTC3887 are dual output poly-phase step-down
 134 - DC/DC controllers.
 135 - LTC3883 is a single phase step-down DC/DC controller.
 136 - LTM2987 is a 16-channel Power System Manager with two LTC2977 plus
 137 - additional components on a single die. The chip is instantiated and reported
 138 - as two separate chips on two different I2C bus addresses.
 139 - LTM4675 is a dual 9A or single 18A μModule regulator
 140 - LTM4676 is a dual 13A or single 26A uModule regulator.
 141 - LTM4686 is a dual 10A or single 20A uModule regulator.
 142
 143
 144 Usage Notes
 145 -----------
 146
 147 This driver does not probe for PMBus devices. You will have to instantiate
 148 devices explicitly.
 149
 150 Example: the following commands will load the driver for an LTC2978 at address
 151 0x60 on I2C bus #1::
 152
 153         # modprobe ltc2978
 154         # echo ltc2978 0x60 > /sys/bus/i2c/devices/i2c-1/new_device
 155
 156
 157 Sysfs attributes
 158 ----------------
 159
 160 ======================= ========================================================
 161 in1_label               "vin"
 162
 163 in1_input               Measured input voltage.
 164
 165 in1_min                 Minimum input voltage.
 166
 167 in1_max                 Maximum input voltage.
 168
 169                         LTC2974, LTC2975, LTC2977, LTC2980, LTC2978, and
 170                         LTM2987 only.
 171
 172 in1_lcrit               Critical minimum input voltage.
 173
 174                         LTC2974, LTC2975, LTC2977, LTC2980, LTC2978, and
 175                         LTM2987 only.
 176
 177 in1_crit                Critical maximum input voltage.
 178
 179 in1_min_alarm           Input voltage low alarm.
 180
 181 in1_max_alarm           Input voltage high alarm.
 182
 183                         LTC2974, LTC2975, LTC2977, LTC2980, LTC2978, and
 184                         LTM2987 only.
 185 in1_lcrit_alarm         Input voltage critical low alarm.
 186
 187                         LTC2974, LTC2975, LTC2977, LTC2980, LTC2978, and
 188                         LTM2987 only.
 189 in1_crit_alarm          Input voltage critical high alarm.
 190
 191 in1_lowest              Lowest input voltage.
 192
 193                         LTC2974, LTC2975, LTC2977, LTC2980, LTC2978, and
 194                         LTM2987 only.
 195 in1_highest             Highest input voltage.
 196
 197 in1_reset_history       Reset input voltage history.
 198
 199 in[N]_label             "vout[1-8]".
 200
 201                         - LTC2974, LTC2975: N=2-5
 202                         - LTC2977, LTC2980, LTM2987: N=2-9
 203                         - LTC2978: N=2-9
 204                         - LTC3880, LTC3882, LTC23886 LTC3887, LTM4675, LTM4676:
 205                           N=2-3
 206                         - LTC3883: N=2
 207
 208 in[N]_input             Measured output voltage.
 209
 210 in[N]_min               Minimum output voltage.
 211
 212 in[N]_max               Maximum output voltage.
 213
 214 in[N]_lcrit             Critical minimum output voltage.
 215
 216 in[N]_crit              Critical maximum output voltage.
 217
 218 in[N]_min_alarm         Output voltage low alarm.
 219
 220 in[N]_max_alarm         Output voltage high alarm.
 221
 222 in[N]_lcrit_alarm       Output voltage critical low alarm.
 223
 224 in[N]_crit_alarm        Output voltage critical high alarm.
 225
 226 in[N]_lowest            Lowest output voltage.
 227
 228
 229                         LTC2974, LTC2975,and LTC2978 only.
 230
 231 in[N]_highest           Highest output voltage.
 232
 233 in[N]_reset_history     Reset output voltage history.
 234
 235 temp[N]_input           Measured temperature.
 236
 237                         - On LTC2974 and LTC2975, temp[1-4] report external
 238                           temperatures, and temp5 reports the chip temperature.
 239                         - On LTC2977, LTC2980, LTC2978, and LTM2987, only one
 240                           temperature measurement is supported and reports
 241                           the chip temperature.
 242                         - On LTC3880, LTC3882, LTC3887, LTM4675, and LTM4676,
 243                           temp1 and temp2 report external temperatures, and
 244                           temp3 reports the chip temperature.
 245                         - On LTC3883, temp1 reports an external temperature,
 246                           and temp2 reports the chip temperature.
 247
 248 temp[N]_min             Mimimum temperature.
 249
 250                         LTC2974, LCT2977, LTM2980, LTC2978, and LTM2987 only.
 251
 252 temp[N]_max             Maximum temperature.
 253
 254 temp[N]_lcrit           Critical low temperature.
 255
 256 temp[N]_crit            Critical high temperature.
 257
 258 temp[N]_min_alarm       Temperature low alarm.
 259
 260                         LTC2974, LTC2975, LTC2977, LTM2980, LTC2978, and
 261                         LTM2987 only.
 262
 263 temp[N]_max_alarm       Temperature high alarm.
 264
 265
 266 temp[N]_lcrit_alarm     Temperature critical low alarm.
 267
 268 temp[N]_crit_alarm      Temperature critical high alarm.
 269
 270 temp[N]_lowest          Lowest measured temperature.
 271
 272                         - LTC2974, LTC2975, LTC2977, LTM2980, LTC2978, and
 273                           LTM2987 only.
 274                         - Not supported for chip temperature sensor on LTC2974
 275                           and LTC2975.
 276
 277 temp[N]_highest         Highest measured temperature.
 278
 279                         Not supported for chip temperature sensor on
 280                         LTC2974 and LTC2975.
 281
 282 temp[N]_reset_history   Reset temperature history.
 283
 284                         Not supported for chip temperature sensor on
 285                         LTC2974 and LTC2975.
 286
 287 power1_label            "pin". LTC3883 and LTC3886 only.
 288
 289 power1_input            Measured input power.
 290
 291 power[N]_label          "pout[1-4]".
 292
 293                         - LTC2974, LTC2975: N=1-4
 294                         - LTC2977, LTC2980, LTM2987: Not supported
 295                         - LTC2978: Not supported
 296                         - LTC3880, LTC3882, LTC3886, LTC3887, LTM4675, LTM4676:
 297                           N=1-2
 298                         - LTC3883: N=2
 299
 300 power[N]_input          Measured output power.
 301
 302 curr1_label             "iin".
 303
 304                         LTC3880, LTC3883, LTC3886, LTC3887, LTM4675,
 305                         and LTM4676 only.
 306
 307 curr1_input             Measured input current.
 308
 309 curr1_max               Maximum input current.
 310
 311 curr1_max_alarm         Input current high alarm.
 312
 313 curr1_highest           Highest input current.
 314
 315                         LTC3883 and LTC3886 only.
 316
 317 curr1_reset_history     Reset input current history.
 318
 319                         LTC3883 and LTC3886 only.
 320
 321 curr[N]_label           "iout[1-4]".
 322
 323                         - LTC2974, LTC2975: N=1-4
 324                         - LTC2977, LTC2980, LTM2987: not supported
 325                         - LTC2978: not supported
 326                         - LTC3880, LTC3882, LTC3886, LTC3887, LTM4675, LTM4676:
 327                           N=2-3
 328                         - LTC3883: N=2
 329
 330 curr[N]_input           Measured output current.
 331
 332 curr[N]_max             Maximum output current.
 333
 334 curr[N]_crit            Critical high output current.
 335
 336 curr[N]_lcrit           Critical low output current.
 337
 338                         LTC2974 and LTC2975 only.
 339
 340 curr[N]_max_alarm       Output current high alarm.
 341
 342 curr[N]_crit_alarm      Output current critical high alarm.
 343
 344 curr[N]_lcrit_alarm     Output current critical low alarm.
 345
 346                         LTC2974 and LTC2975 only.
 347
 348 curr[N]_lowest          Lowest output current.
 349
 350                         LTC2974 and LTC2975 only.
 351
 352 curr[N]_highest         Highest output current.
 353
 354 curr[N]_reset_history   Reset output current history.
 355 ======================= ========================================================