1*4882a593SmuzhiyunKernel driver jc42 2*4882a593Smuzhiyun================== 3*4882a593Smuzhiyun 4*4882a593SmuzhiyunSupported chips: 5*4882a593Smuzhiyun 6*4882a593Smuzhiyun * Analog Devices ADT7408 7*4882a593Smuzhiyun 8*4882a593Smuzhiyun Datasheets: 9*4882a593Smuzhiyun 10*4882a593Smuzhiyun https://www.analog.com/static/imported-files/data_sheets/ADT7408.pdf 11*4882a593Smuzhiyun 12*4882a593Smuzhiyun * Atmel AT30TS00, AT30TS002A/B, AT30TSE004A 13*4882a593Smuzhiyun 14*4882a593Smuzhiyun Datasheets: 15*4882a593Smuzhiyun 16*4882a593Smuzhiyun http://www.atmel.com/Images/doc8585.pdf 17*4882a593Smuzhiyun 18*4882a593Smuzhiyun http://www.atmel.com/Images/doc8711.pdf 19*4882a593Smuzhiyun 20*4882a593Smuzhiyun http://www.atmel.com/Images/Atmel-8852-SEEPROM-AT30TSE002A-Datasheet.pdf 21*4882a593Smuzhiyun 22*4882a593Smuzhiyun http://www.atmel.com/Images/Atmel-8868-DTS-AT30TSE004A-Datasheet.pdf 23*4882a593Smuzhiyun 24*4882a593Smuzhiyun * IDT TSE2002B3, TSE2002GB2, TSE2004GB2, TS3000B3, TS3000GB0, TS3000GB2, 25*4882a593Smuzhiyun 26*4882a593Smuzhiyun TS3001GB2 27*4882a593Smuzhiyun 28*4882a593Smuzhiyun Datasheets: 29*4882a593Smuzhiyun 30*4882a593Smuzhiyun Available from IDT web site 31*4882a593Smuzhiyun 32*4882a593Smuzhiyun * Maxim MAX6604 33*4882a593Smuzhiyun 34*4882a593Smuzhiyun Datasheets: 35*4882a593Smuzhiyun 36*4882a593Smuzhiyun http://datasheets.maxim-ic.com/en/ds/MAX6604.pdf 37*4882a593Smuzhiyun 38*4882a593Smuzhiyun * Microchip MCP9804, MCP9805, MCP9808, MCP98242, MCP98243, MCP98244, MCP9843 39*4882a593Smuzhiyun 40*4882a593Smuzhiyun Datasheets: 41*4882a593Smuzhiyun 42*4882a593Smuzhiyun https://ww1.microchip.com/downloads/en/DeviceDoc/22203C.pdf 43*4882a593Smuzhiyun 44*4882a593Smuzhiyun https://ww1.microchip.com/downloads/en/DeviceDoc/21977b.pdf 45*4882a593Smuzhiyun 46*4882a593Smuzhiyun https://ww1.microchip.com/downloads/en/DeviceDoc/25095A.pdf 47*4882a593Smuzhiyun 48*4882a593Smuzhiyun https://ww1.microchip.com/downloads/en/DeviceDoc/21996a.pdf 49*4882a593Smuzhiyun 50*4882a593Smuzhiyun https://ww1.microchip.com/downloads/en/DeviceDoc/22153c.pdf 51*4882a593Smuzhiyun 52*4882a593Smuzhiyun https://ww1.microchip.com/downloads/en/DeviceDoc/22327A.pdf 53*4882a593Smuzhiyun 54*4882a593Smuzhiyun * NXP Semiconductors SE97, SE97B, SE98, SE98A 55*4882a593Smuzhiyun 56*4882a593Smuzhiyun Datasheets: 57*4882a593Smuzhiyun 58*4882a593Smuzhiyun https://www.nxp.com/documents/data_sheet/SE97.pdf 59*4882a593Smuzhiyun 60*4882a593Smuzhiyun https://www.nxp.com/documents/data_sheet/SE97B.pdf 61*4882a593Smuzhiyun 62*4882a593Smuzhiyun https://www.nxp.com/documents/data_sheet/SE98.pdf 63*4882a593Smuzhiyun 64*4882a593Smuzhiyun https://www.nxp.com/documents/data_sheet/SE98A.pdf 65*4882a593Smuzhiyun 66*4882a593Smuzhiyun * ON Semiconductor CAT34TS02, CAT6095 67*4882a593Smuzhiyun 68*4882a593Smuzhiyun Datasheet: 69*4882a593Smuzhiyun 70*4882a593Smuzhiyun https://www.onsemi.com/pub_link/Collateral/CAT34TS02-D.PDF 71*4882a593Smuzhiyun 72*4882a593Smuzhiyun https://www.onsemi.com/pub/Collateral/CAT6095-D.PDF 73*4882a593Smuzhiyun 74*4882a593Smuzhiyun * ST Microelectronics STTS424, STTS424E02, STTS2002, STTS2004, STTS3000 75*4882a593Smuzhiyun 76*4882a593Smuzhiyun Datasheets: 77*4882a593Smuzhiyun 78*4882a593Smuzhiyun http://www.st.com/web/en/resource/technical/document/datasheet/CD00157556.pdf 79*4882a593Smuzhiyun 80*4882a593Smuzhiyun http://www.st.com/web/en/resource/technical/document/datasheet/CD00157558.pdf 81*4882a593Smuzhiyun 82*4882a593Smuzhiyun http://www.st.com/web/en/resource/technical/document/datasheet/CD00266638.pdf 83*4882a593Smuzhiyun 84*4882a593Smuzhiyun http://www.st.com/web/en/resource/technical/document/datasheet/CD00225278.pdf 85*4882a593Smuzhiyun 86*4882a593Smuzhiyun http://www.st.com/web/en/resource/technical/document/datasheet/DM00076709.pdf 87*4882a593Smuzhiyun 88*4882a593Smuzhiyun * JEDEC JC 42.4 compliant temperature sensor chips 89*4882a593Smuzhiyun 90*4882a593Smuzhiyun Datasheet: 91*4882a593Smuzhiyun 92*4882a593Smuzhiyun http://www.jedec.org/sites/default/files/docs/4_01_04R19.pdf 93*4882a593Smuzhiyun 94*4882a593Smuzhiyun 95*4882a593Smuzhiyun Common for all chips: 96*4882a593Smuzhiyun 97*4882a593Smuzhiyun Prefix: 'jc42' 98*4882a593Smuzhiyun 99*4882a593Smuzhiyun Addresses scanned: I2C 0x18 - 0x1f 100*4882a593Smuzhiyun 101*4882a593SmuzhiyunAuthor: 102*4882a593Smuzhiyun Guenter Roeck <linux@roeck-us.net> 103*4882a593Smuzhiyun 104*4882a593Smuzhiyun 105*4882a593SmuzhiyunDescription 106*4882a593Smuzhiyun----------- 107*4882a593Smuzhiyun 108*4882a593SmuzhiyunThis driver implements support for JEDEC JC 42.4 compliant temperature sensors, 109*4882a593Smuzhiyunwhich are used on many DDR3 memory modules for mobile devices and servers. Some 110*4882a593Smuzhiyunsystems use the sensor to prevent memory overheating by automatically throttling 111*4882a593Smuzhiyunthe memory controller. 112*4882a593Smuzhiyun 113*4882a593SmuzhiyunThe driver auto-detects the chips listed above, but can be manually instantiated 114*4882a593Smuzhiyunto support other JC 42.4 compliant chips. 115*4882a593Smuzhiyun 116*4882a593SmuzhiyunExample: the following will load the driver for a generic JC 42.4 compliant 117*4882a593Smuzhiyuntemperature sensor at address 0x18 on I2C bus #1:: 118*4882a593Smuzhiyun 119*4882a593Smuzhiyun # modprobe jc42 120*4882a593Smuzhiyun # echo jc42 0x18 > /sys/bus/i2c/devices/i2c-1/new_device 121*4882a593Smuzhiyun 122*4882a593SmuzhiyunA JC 42.4 compliant chip supports a single temperature sensor. Minimum, maximum, 123*4882a593Smuzhiyunand critical temperature can be configured. There are alarms for high, low, 124*4882a593Smuzhiyunand critical thresholds. 125*4882a593Smuzhiyun 126*4882a593SmuzhiyunThere is also an hysteresis to control the thresholds for resetting alarms. 127*4882a593SmuzhiyunPer JC 42.4 specification, the hysteresis threshold can be configured to 0, 1.5, 128*4882a593Smuzhiyun3.0, and 6.0 degrees C. Configured hysteresis values will be rounded to those 129*4882a593Smuzhiyunlimits. The chip supports only a single register to configure the hysteresis, 130*4882a593Smuzhiyunwhich applies to all limits. This register can be written by writing into 131*4882a593Smuzhiyuntemp1_crit_hyst. Other hysteresis attributes are read-only. 132*4882a593Smuzhiyun 133*4882a593SmuzhiyunIf the BIOS has configured the sensor for automatic temperature management, it 134*4882a593Smuzhiyunis likely that it has locked the registers, i.e., that the temperature limits 135*4882a593Smuzhiyuncannot be changed. 136*4882a593Smuzhiyun 137*4882a593SmuzhiyunSysfs entries 138*4882a593Smuzhiyun------------- 139*4882a593Smuzhiyun 140*4882a593Smuzhiyun======================= =========================================== 141*4882a593Smuzhiyuntemp1_input Temperature (RO) 142*4882a593Smuzhiyuntemp1_min Minimum temperature (RO or RW) 143*4882a593Smuzhiyuntemp1_max Maximum temperature (RO or RW) 144*4882a593Smuzhiyuntemp1_crit Critical high temperature (RO or RW) 145*4882a593Smuzhiyun 146*4882a593Smuzhiyuntemp1_crit_hyst Critical hysteresis temperature (RO or RW) 147*4882a593Smuzhiyuntemp1_max_hyst Maximum hysteresis temperature (RO) 148*4882a593Smuzhiyun 149*4882a593Smuzhiyuntemp1_min_alarm Temperature low alarm 150*4882a593Smuzhiyuntemp1_max_alarm Temperature high alarm 151*4882a593Smuzhiyuntemp1_crit_alarm Temperature critical alarm 152*4882a593Smuzhiyun======================= =========================================== 153