ltc2978.rst (10164B)
1Kernel driver ltc2978 2===================== 3 4Supported chips: 5 6 * Linear Technology LTC2972 7 8 Prefix: 'ltc2972' 9 10 Addresses scanned: - 11 12 Datasheet: https://www.analog.com/en/products/ltc2972.html 13 14 * Linear Technology LTC2974 15 16 Prefix: 'ltc2974' 17 18 Addresses scanned: - 19 20 Datasheet: https://www.analog.com/en/products/ltc2974 21 22 * Linear Technology LTC2975 23 24 Prefix: 'ltc2975' 25 26 Addresses scanned: - 27 28 Datasheet: https://www.analog.com/en/products/ltc2975 29 30 * Linear Technology LTC2977 31 32 Prefix: 'ltc2977' 33 34 Addresses scanned: - 35 36 Datasheet: https://www.analog.com/en/products/ltc2977 37 38 * Linear Technology LTC2978, LTC2978A 39 40 Prefix: 'ltc2978' 41 42 Addresses scanned: - 43 44 Datasheet: https://www.analog.com/en/products/ltc2978 45 46 https://www.analog.com/en/products/ltc2978a 47 48 * Linear Technology LTC2979 49 50 Prefix: 'ltc2979' 51 52 Addresses scanned: - 53 54 Datasheet: https://www.analog.com/en/products/ltc2979 55 56 * Linear Technology LTC2980 57 58 Prefix: 'ltc2980' 59 60 Addresses scanned: - 61 62 Datasheet: https://www.analog.com/en/products/ltc2980 63 64 * Linear Technology LTC3880 65 66 Prefix: 'ltc3880' 67 68 Addresses scanned: - 69 70 Datasheet: https://www.analog.com/en/products/ltc3880 71 72 * Linear Technology LTC3882 73 74 Prefix: 'ltc3882' 75 76 Addresses scanned: - 77 78 Datasheet: https://www.analog.com/en/products/ltc3882 79 80 * Linear Technology LTC3883 81 82 Prefix: 'ltc3883' 83 84 Addresses scanned: - 85 86 Datasheet: https://www.analog.com/en/products/ltc3883 87 88 * Linear Technology LTC3884 89 90 Prefix: 'ltc3884' 91 92 Addresses scanned: - 93 94 Datasheet: https://www.analog.com/en/products/ltc3884 95 96 * Linear Technology LTC3886 97 98 Prefix: 'ltc3886' 99 100 Addresses scanned: - 101 102 Datasheet: https://www.analog.com/en/products/ltc3886 103 104 * Linear Technology LTC3887 105 106 Prefix: 'ltc3887' 107 108 Addresses scanned: - 109 110 Datasheet: https://www.analog.com/en/products/ltc3887 111 112 * Linear Technology LTC3889 113 114 Prefix: 'ltc3889' 115 116 Addresses scanned: - 117 118 Datasheet: https://www.analog.com/en/products/ltc3889 119 120 * Linear Technology LTC7880 121 122 Prefix: 'ltc7880' 123 124 Addresses scanned: - 125 126 Datasheet: https://www.analog.com/en/products/ltc7880 127 128 * Linear Technology LTM2987 129 130 Prefix: 'ltm2987' 131 132 Addresses scanned: - 133 134 Datasheet: https://www.analog.com/en/products/ltm2987 135 136 * Linear Technology LTM4644 137 138 Prefix: 'ltm4644' 139 140 Addresses scanned: - 141 142 Datasheet: https://www.analog.com/en/products/ltm4644 143 144 * Linear Technology LTM4675 145 146 Prefix: 'ltm4675' 147 148 Addresses scanned: - 149 150 Datasheet: https://www.analog.com/en/products/ltm4675 151 152 * Linear Technology LTM4676 153 154 Prefix: 'ltm4676' 155 156 Addresses scanned: - 157 158 Datasheet: https://www.analog.com/en/products/ltm4676 159 160 * Linear Technology LTM4677 161 162 Prefix: 'ltm4677' 163 164 Addresses scanned: - 165 166 Datasheet: https://www.analog.com/en/products/ltm4677 167 168 * Linear Technology LTM4678 169 170 Prefix: 'ltm4678' 171 172 Addresses scanned: - 173 174 Datasheet: https://www.analog.com/en/products/ltm4678 175 176 * Analog Devices LTM4680 177 178 Prefix: 'ltm4680' 179 180 Addresses scanned: - 181 182 Datasheet: https://www.analog.com/ltm4680 183 184 * Analog Devices LTM4686 185 186 Prefix: 'ltm4686' 187 188 Addresses scanned: - 189 190 Datasheet: https://www.analog.com/ltm4686 191 192 * Analog Devices LTM4700 193 194 Prefix: 'ltm4700' 195 196 Addresses scanned: - 197 198 Datasheet: https://www.analog.com/ltm4700 199 200 201 202Author: Guenter Roeck <linux@roeck-us.net> 203 204 205Description 206----------- 207 208- LTC2974 and LTC2975 are quad digital power supply managers. 209- LTC2978 is an octal power supply monitor. 210- LTC2977 is a pin compatible replacement for LTC2978. 211- LTC2980 is a 16-channel Power System Manager, consisting of two LTC2977 212- in a single die. The chip is instantiated and reported as two separate chips 213- on two different I2C bus addresses. 214- LTC3880, LTC3882, LTC3886, and LTC3887 are dual output poly-phase step-down 215- DC/DC controllers. 216- LTC3883 is a single phase step-down DC/DC controller. 217- LTM2987 is a 16-channel Power System Manager with two LTC2977 plus 218- additional components on a single die. The chip is instantiated and reported 219- as two separate chips on two different I2C bus addresses. 220- LTM4675 is a dual 9A or single 18A μModule regulator 221- LTM4676 is a dual 13A or single 26A uModule regulator. 222- LTM4686 is a dual 10A or single 20A uModule regulator. 223 224 225Usage Notes 226----------- 227 228This driver does not probe for PMBus devices. You will have to instantiate 229devices explicitly. 230 231Example: the following commands will load the driver for an LTC2978 at address 2320x60 on I2C bus #1:: 233 234 # modprobe ltc2978 235 # echo ltc2978 0x60 > /sys/bus/i2c/devices/i2c-1/new_device 236 237 238Sysfs attributes 239---------------- 240 241======================= ======================================================== 242in1_label "vin" 243 244in1_input Measured input voltage. 245 246in1_min Minimum input voltage. 247 248in1_max Maximum input voltage. 249 250 LTC2974, LTC2975, LTC2977, LTC2980, LTC2978, 251 LTC2979 and LTM2987 only. 252 253in1_lcrit Critical minimum input voltage. 254 255 LTC2972, LTC2974, LTC2975, LTC2977, LTC2980, LTC2978, 256 LTC2979 and LTM2987 only. 257 258in1_crit Critical maximum input voltage. 259 260in1_min_alarm Input voltage low alarm. 261 262in1_max_alarm Input voltage high alarm. 263 264 LTC2972, LTC2974, LTC2975, LTC2977, LTC2980, LTC2978, 265 LTC2979 and LTM2987 only. 266 267in1_lcrit_alarm Input voltage critical low alarm. 268 269 LTC2972, LTC2974, LTC2975, LTC2977, LTC2980, LTC2978, 270 LTC2979 and LTM2987 only. 271 272in1_crit_alarm Input voltage critical high alarm. 273 274in1_lowest Lowest input voltage. 275 276 LTC2972, LTC2974, LTC2975, LTC2977, LTC2980, LTC2978, 277 and LTM2987 only. 278 279in1_highest Highest input voltage. 280 281in1_reset_history Reset input voltage history. 282 283in[N]_label "vout[1-8]". 284 285 - LTC2972: N=2-3 286 - LTC2974, LTC2975: N=2-5 287 - LTC2977, LTC2979, LTC2980, LTM2987: N=2-9 288 - LTC2978: N=2-9 289 - LTC3880, LTC3882, LTC3884, LTC23886 LTC3887, LTC3889, 290 LTC7880, LTM4644, LTM4675, LTM4676, LTM4677, LTM4678, 291 LTM4680, LTM4700: N=2-3 292 - LTC3883: N=2 293 294in[N]_input Measured output voltage. 295 296in[N]_min Minimum output voltage. 297 298in[N]_max Maximum output voltage. 299 300in[N]_lcrit Critical minimum output voltage. 301 302in[N]_crit Critical maximum output voltage. 303 304in[N]_min_alarm Output voltage low alarm. 305 306in[N]_max_alarm Output voltage high alarm. 307 308in[N]_lcrit_alarm Output voltage critical low alarm. 309 310in[N]_crit_alarm Output voltage critical high alarm. 311 312in[N]_lowest Lowest output voltage. 313 314 LTC2972, LTC2974, LTC2975,and LTC2978 only. 315 316in[N]_highest Highest output voltage. 317 318in[N]_reset_history Reset output voltage history. 319 320temp[N]_input Measured temperature. 321 322 - On LTC2972, temp[1-2] report external temperatures, 323 and temp 3 reports the chip temperature. 324 - On LTC2974 and LTC2975, temp[1-4] report external 325 temperatures, and temp5 reports the chip temperature. 326 - On LTC2977, LTC2979, LTC2980, LTC2978, and LTM2987, 327 only one temperature measurement is supported and 328 reports the chip temperature. 329 - On LTC3880, LTC3882, LTC3886, LTC3887, LTC3889, 330 LTM4664, LTM4675, LTM4676, LTM4677, LTM4678, LTM4680, 331 and LTM4700, temp1 and temp2 report external 332 temperatures, and temp3 reports the chip temperature. 333 - On LTC3883, temp1 reports an external temperature, 334 and temp2 reports the chip temperature. 335 336temp[N]_min Mimimum temperature. 337 338 LTC2972, LTC2974, LCT2977, LTM2980, LTC2978, 339 LTC2979, and LTM2987 only. 340 341temp[N]_max Maximum temperature. 342 343temp[N]_lcrit Critical low temperature. 344 345temp[N]_crit Critical high temperature. 346 347temp[N]_min_alarm Temperature low alarm. 348 349 LTC2972, LTC2974, LTC2975, LTC2977, LTM2980, LTC2978, 350 LTC2979, and LTM2987 only. 351 352temp[N]_max_alarm Temperature high alarm. 353 354 355temp[N]_lcrit_alarm Temperature critical low alarm. 356 357temp[N]_crit_alarm Temperature critical high alarm. 358 359temp[N]_lowest Lowest measured temperature. 360 361 - LTC2972, LTC2974, LTC2975, LTC2977, LTM2980, LTC2978, 362 LTC2979, and LTM2987 only. 363 - Not supported for chip temperature sensor on LTC2974 364 and LTC2975. 365 366temp[N]_highest Highest measured temperature. 367 368 Not supported for chip temperature sensor on 369 LTC2974 and LTC2975. 370 371temp[N]_reset_history Reset temperature history. 372 373 Not supported for chip temperature sensor on 374 LTC2974 and LTC2975. 375 376power1_label "pin". LTC3883 and LTC3886 only. 377 378power1_input Measured input power. 379 380power[N]_label "pout[1-4]". 381 382 - LTC2972: N=1-2 383 - LTC2974, LTC2975: N=1-4 384 - LTC2977, LTC2979, LTC2980, LTM2987: Not supported 385 - LTC2978: Not supported 386 - LTC3880, LTC3882, LTC3884, LTC3886, LTC3887, LTC3889, 387 LTM4664, LTM4675, LTM4676, LTM4677, LTM4678, LTM4680, 388 LTM4700: N=1-2 389 - LTC3883: N=2 390 391power[N]_input Measured output power. 392 393curr1_label "iin". 394 395 LTC3880, LTC3883, LTC3884, LTC3886, LTC3887, LTC3889, 396 LTM4644, LTM4675, LTM4676, LTM4677, LTM4678, LTM4680, 397 and LTM4700 only. 398 399curr1_input Measured input current. 400 401curr1_max Maximum input current. 402 403curr1_max_alarm Input current high alarm. 404 405curr1_highest Highest input current. 406 407 LTC3883 and LTC3886 only. 408 409curr1_reset_history Reset input current history. 410 411 LTC3883 and LTC3886 only. 412 413curr[N]_label "iout[1-4]". 414 415 - LTC2972: N-1-2 416 - LTC2974, LTC2975: N=1-4 417 - LTC2977, LTC2979, LTC2980, LTM2987: not supported 418 - LTC2978: not supported 419 - LTC3880, LTC3882, LTC3884, LTC3886, LTC3887, LTC3889, 420 LTM4664, LTM4675, LTM4676, LTM4677, LTM4678, LTM4680, 421 LTM4700: N=2-3 422 - LTC3883: N=2 423 424curr[N]_input Measured output current. 425 426curr[N]_max Maximum output current. 427 428curr[N]_crit Critical high output current. 429 430curr[N]_lcrit Critical low output current. 431 432 LTC2972, LTC2974 and LTC2975 only. 433 434curr[N]_max_alarm Output current high alarm. 435 436curr[N]_crit_alarm Output current critical high alarm. 437 438curr[N]_lcrit_alarm Output current critical low alarm. 439 440 LTC2972, LTC2974 and LTC2975 only. 441 442curr[N]_lowest Lowest output current. 443 444 LTC2972, LTC2974 and LTC2975 only. 445 446curr[N]_highest Highest output current. 447 448curr[N]_reset_history Reset output current history. 449======================= ========================================================