17ebd8b66SMauro Carvalho ChehabKernel driver lm95234 27ebd8b66SMauro Carvalho Chehab===================== 37ebd8b66SMauro Carvalho Chehab 47ebd8b66SMauro Carvalho ChehabSupported chips: 57ebd8b66SMauro Carvalho Chehab 67ebd8b66SMauro Carvalho Chehab * National Semiconductor / Texas Instruments LM95233 77ebd8b66SMauro Carvalho Chehab 87ebd8b66SMauro Carvalho Chehab Addresses scanned: I2C 0x18, 0x2a, 0x2b 97ebd8b66SMauro Carvalho Chehab 107ebd8b66SMauro Carvalho Chehab Datasheet: Publicly available at the Texas Instruments website 117ebd8b66SMauro Carvalho Chehab 12*fdf41645SAlexander A. Klimov https://www.ti.com/product/lm95233 137ebd8b66SMauro Carvalho Chehab 147ebd8b66SMauro Carvalho Chehab * National Semiconductor / Texas Instruments LM95234 157ebd8b66SMauro Carvalho Chehab 167ebd8b66SMauro Carvalho Chehab Addresses scanned: I2C 0x18, 0x4d, 0x4e 177ebd8b66SMauro Carvalho Chehab 187ebd8b66SMauro Carvalho Chehab Datasheet: Publicly available at the Texas Instruments website 197ebd8b66SMauro Carvalho Chehab 20*fdf41645SAlexander A. Klimov https://www.ti.com/product/lm95234 217ebd8b66SMauro Carvalho Chehab 227ebd8b66SMauro Carvalho ChehabAuthor: Guenter Roeck <linux@roeck-us.net> 237ebd8b66SMauro Carvalho Chehab 247ebd8b66SMauro Carvalho ChehabDescription 257ebd8b66SMauro Carvalho Chehab----------- 267ebd8b66SMauro Carvalho Chehab 277ebd8b66SMauro Carvalho ChehabLM95233 and LM95234 are 11-bit digital temperature sensors with a 2-wire 287ebd8b66SMauro Carvalho ChehabSystem Management Bus (SMBus) interface and TrueTherm technology 297ebd8b66SMauro Carvalho Chehabthat can very accurately monitor the temperature of two (LM95233) 307ebd8b66SMauro Carvalho Chehabor four (LM95234) remote diodes as well as its own temperature. 317ebd8b66SMauro Carvalho ChehabThe remote diodes can be external devices such as microprocessors, 327ebd8b66SMauro Carvalho Chehabgraphics processors or diode-connected 2N3904s. The chip's TruTherm 337ebd8b66SMauro Carvalho Chehabbeta compensation technology allows sensing of 90 nm or 65 nm process 347ebd8b66SMauro Carvalho Chehabthermal diodes accurately. 357ebd8b66SMauro Carvalho Chehab 367ebd8b66SMauro Carvalho ChehabAll temperature values are given in millidegrees Celsius. Temperature 377ebd8b66SMauro Carvalho Chehabis provided within a range of -127 to +255 degrees (+127.875 degrees for 387ebd8b66SMauro Carvalho Chehabthe internal sensor). Resolution depends on temperature input and range. 397ebd8b66SMauro Carvalho Chehab 407ebd8b66SMauro Carvalho ChehabEach sensor has its own maximum limit, but the hysteresis is common to all 417ebd8b66SMauro Carvalho Chehabchannels. The hysteresis is configurable with the tem1_max_hyst attribute and 427ebd8b66SMauro Carvalho Chehabaffects the hysteresis on all channels. The first two external sensors also 437ebd8b66SMauro Carvalho Chehabhave a critical limit. 447ebd8b66SMauro Carvalho Chehab 457ebd8b66SMauro Carvalho ChehabThe lm95234 driver can change its update interval to a fixed set of values. 467ebd8b66SMauro Carvalho ChehabIt will round up to the next selectable interval. See the datasheet for exact 477ebd8b66SMauro Carvalho Chehabvalues. Reading sensor values more often will do no harm, but will return 487ebd8b66SMauro Carvalho Chehab'old' values. 49