1*4882a593SmuzhiyunKernel driver lm95234 2*4882a593Smuzhiyun===================== 3*4882a593Smuzhiyun 4*4882a593SmuzhiyunSupported chips: 5*4882a593Smuzhiyun 6*4882a593Smuzhiyun * National Semiconductor / Texas Instruments LM95233 7*4882a593Smuzhiyun 8*4882a593Smuzhiyun Addresses scanned: I2C 0x18, 0x2a, 0x2b 9*4882a593Smuzhiyun 10*4882a593Smuzhiyun Datasheet: Publicly available at the Texas Instruments website 11*4882a593Smuzhiyun 12*4882a593Smuzhiyun https://www.ti.com/product/lm95233 13*4882a593Smuzhiyun 14*4882a593Smuzhiyun * National Semiconductor / Texas Instruments LM95234 15*4882a593Smuzhiyun 16*4882a593Smuzhiyun Addresses scanned: I2C 0x18, 0x4d, 0x4e 17*4882a593Smuzhiyun 18*4882a593Smuzhiyun Datasheet: Publicly available at the Texas Instruments website 19*4882a593Smuzhiyun 20*4882a593Smuzhiyun https://www.ti.com/product/lm95234 21*4882a593Smuzhiyun 22*4882a593SmuzhiyunAuthor: Guenter Roeck <linux@roeck-us.net> 23*4882a593Smuzhiyun 24*4882a593SmuzhiyunDescription 25*4882a593Smuzhiyun----------- 26*4882a593Smuzhiyun 27*4882a593SmuzhiyunLM95233 and LM95234 are 11-bit digital temperature sensors with a 2-wire 28*4882a593SmuzhiyunSystem Management Bus (SMBus) interface and TrueTherm technology 29*4882a593Smuzhiyunthat can very accurately monitor the temperature of two (LM95233) 30*4882a593Smuzhiyunor four (LM95234) remote diodes as well as its own temperature. 31*4882a593SmuzhiyunThe remote diodes can be external devices such as microprocessors, 32*4882a593Smuzhiyungraphics processors or diode-connected 2N3904s. The chip's TruTherm 33*4882a593Smuzhiyunbeta compensation technology allows sensing of 90 nm or 65 nm process 34*4882a593Smuzhiyunthermal diodes accurately. 35*4882a593Smuzhiyun 36*4882a593SmuzhiyunAll temperature values are given in millidegrees Celsius. Temperature 37*4882a593Smuzhiyunis provided within a range of -127 to +255 degrees (+127.875 degrees for 38*4882a593Smuzhiyunthe internal sensor). Resolution depends on temperature input and range. 39*4882a593Smuzhiyun 40*4882a593SmuzhiyunEach sensor has its own maximum limit, but the hysteresis is common to all 41*4882a593Smuzhiyunchannels. The hysteresis is configurable with the tem1_max_hyst attribute and 42*4882a593Smuzhiyunaffects the hysteresis on all channels. The first two external sensors also 43*4882a593Smuzhiyunhave a critical limit. 44*4882a593Smuzhiyun 45*4882a593SmuzhiyunThe lm95234 driver can change its update interval to a fixed set of values. 46*4882a593SmuzhiyunIt will round up to the next selectable interval. See the datasheet for exact 47*4882a593Smuzhiyunvalues. Reading sensor values more often will do no harm, but will return 48*4882a593Smuzhiyun'old' values. 49