1Kernel driver jc42 2================== 3 4Supported chips: 5 * Analog Devices ADT7408 6 Datasheets: 7 http://www.analog.com/static/imported-files/data_sheets/ADT7408.pdf 8 * Atmel AT30TS00 9 Datasheets: 10 http://www.atmel.com/Images/doc8585.pdf 11 * IDT TSE2002B3, TSE2002GB2, TS3000B3, TS3000GB2 12 Datasheets: 13 http://www.idt.com/sites/default/files/documents/IDT_TSE2002B3C_DST_20100512_120303152056.pdf 14 http://www.idt.com/sites/default/files/documents/IDT_TSE2002GB2A1_DST_20111107_120303145914.pdf 15 http://www.idt.com/sites/default/files/documents/IDT_TS3000B3A_DST_20101129_120303152013.pdf 16 http://www.idt.com/sites/default/files/documents/IDT_TS3000GB2A1_DST_20111104_120303151012.pdf 17 * Maxim MAX6604 18 Datasheets: 19 http://datasheets.maxim-ic.com/en/ds/MAX6604.pdf 20 * Microchip MCP9804, MCP9805, MCP98242, MCP98243, MCP98244, MCP9843 21 Datasheets: 22 http://ww1.microchip.com/downloads/en/DeviceDoc/22203C.pdf 23 http://ww1.microchip.com/downloads/en/DeviceDoc/21977b.pdf 24 http://ww1.microchip.com/downloads/en/DeviceDoc/21996a.pdf 25 http://ww1.microchip.com/downloads/en/DeviceDoc/22153c.pdf 26 http://ww1.microchip.com/downloads/en/DeviceDoc/22327A.pdf 27 * NXP Semiconductors SE97, SE97B, SE98, SE98A 28 Datasheets: 29 http://www.nxp.com/documents/data_sheet/SE97.pdf 30 http://www.nxp.com/documents/data_sheet/SE97B.pdf 31 http://www.nxp.com/documents/data_sheet/SE98.pdf 32 http://www.nxp.com/documents/data_sheet/SE98A.pdf 33 * ON Semiconductor CAT34TS02, CAT6095 34 Datasheet: 35 http://www.onsemi.com/pub_link/Collateral/CAT34TS02-D.PDF 36 http://www.onsemi.com/pub/Collateral/CAT6095-D.PDF 37 * ST Microelectronics STTS424, STTS424E02, STTS2002, STTS3000 38 Datasheets: 39 http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/DATASHEET/CD00157556.pdf 40 http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/DATASHEET/CD00157558.pdf 41 http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/DATASHEET/CD00225278.pdf 42 http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/DATA_BRIEF/CD00270920.pdf 43 * JEDEC JC 42.4 compliant temperature sensor chips 44 Datasheet: 45 http://www.jedec.org/sites/default/files/docs/4_01_04R19.pdf 46 47 Common for all chips: 48 Prefix: 'jc42' 49 Addresses scanned: I2C 0x18 - 0x1f 50 51Author: 52 Guenter Roeck <linux@roeck-us.net> 53 54 55Description 56----------- 57 58This driver implements support for JEDEC JC 42.4 compliant temperature sensors, 59which are used on many DDR3 memory modules for mobile devices and servers. Some 60systems use the sensor to prevent memory overheating by automatically throttling 61the memory controller. 62 63The driver auto-detects the chips listed above, but can be manually instantiated 64to support other JC 42.4 compliant chips. 65 66Example: the following will load the driver for a generic JC 42.4 compliant 67temperature sensor at address 0x18 on I2C bus #1: 68 69# modprobe jc42 70# echo jc42 0x18 > /sys/bus/i2c/devices/i2c-1/new_device 71 72A JC 42.4 compliant chip supports a single temperature sensor. Minimum, maximum, 73and critical temperature can be configured. There are alarms for high, low, 74and critical thresholds. 75 76There is also an hysteresis to control the thresholds for resetting alarms. 77Per JC 42.4 specification, the hysteresis threshold can be configured to 0, 1.5, 783.0, and 6.0 degrees C. Configured hysteresis values will be rounded to those 79limits. The chip supports only a single register to configure the hysteresis, 80which applies to all limits. This register can be written by writing into 81temp1_crit_hyst. Other hysteresis attributes are read-only. 82 83If the BIOS has configured the sensor for automatic temperature management, it 84is likely that it has locked the registers, i.e., that the temperature limits 85cannot be changed. 86 87Sysfs entries 88------------- 89 90temp1_input Temperature (RO) 91temp1_min Minimum temperature (RO or RW) 92temp1_max Maximum temperature (RO or RW) 93temp1_crit Critical high temperature (RO or RW) 94 95temp1_crit_hyst Critical hysteresis temperature (RO or RW) 96temp1_max_hyst Maximum hysteresis temperature (RO) 97 98temp1_min_alarm Temperature low alarm 99temp1_max_alarm Temperature high alarm 100temp1_crit_alarm Temperature critical alarm 101