0001 Kernel driver jc42
0002 ==================
0003
0004 Supported chips:
0005
0006 * Analog Devices ADT7408
0007
0008 Datasheets:
0009
0010 https://www.analog.com/static/imported-files/data_sheets/ADT7408.pdf
0011
0012 * Atmel AT30TS00, AT30TS002A/B, AT30TSE004A
0013
0014 Datasheets:
0015
0016 http://www.atmel.com/Images/doc8585.pdf
0017
0018 http://www.atmel.com/Images/doc8711.pdf
0019
0020 http://www.atmel.com/Images/Atmel-8852-SEEPROM-AT30TSE002A-Datasheet.pdf
0021
0022 http://www.atmel.com/Images/Atmel-8868-DTS-AT30TSE004A-Datasheet.pdf
0023
0024 * IDT TSE2002B3, TSE2002GB2, TSE2004GB2, TS3000B3, TS3000GB0, TS3000GB2,
0025
0026 TS3001GB2
0027
0028 Datasheets:
0029
0030 Available from IDT web site
0031
0032 * Maxim MAX6604
0033
0034 Datasheets:
0035
0036 http://datasheets.maxim-ic.com/en/ds/MAX6604.pdf
0037
0038 * Microchip MCP9804, MCP9805, MCP9808, MCP98242, MCP98243, MCP98244, MCP9843
0039
0040 Datasheets:
0041
0042 https://ww1.microchip.com/downloads/en/DeviceDoc/22203C.pdf
0043
0044 https://ww1.microchip.com/downloads/en/DeviceDoc/21977b.pdf
0045
0046 https://ww1.microchip.com/downloads/en/DeviceDoc/25095A.pdf
0047
0048 https://ww1.microchip.com/downloads/en/DeviceDoc/21996a.pdf
0049
0050 https://ww1.microchip.com/downloads/en/DeviceDoc/22153c.pdf
0051
0052 https://ww1.microchip.com/downloads/en/DeviceDoc/22327A.pdf
0053
0054 * NXP Semiconductors SE97, SE97B, SE98, SE98A
0055
0056 Datasheets:
0057
0058 https://www.nxp.com/documents/data_sheet/SE97.pdf
0059
0060 https://www.nxp.com/documents/data_sheet/SE97B.pdf
0061
0062 https://www.nxp.com/documents/data_sheet/SE98.pdf
0063
0064 https://www.nxp.com/documents/data_sheet/SE98A.pdf
0065
0066 * ON Semiconductor CAT34TS02, CAT6095
0067
0068 Datasheet:
0069
0070 https://www.onsemi.com/pub_link/Collateral/CAT34TS02-D.PDF
0071
0072 https://www.onsemi.com/pub/Collateral/CAT6095-D.PDF
0073
0074 * ST Microelectronics STTS424, STTS424E02, STTS2002, STTS2004, STTS3000
0075
0076 Datasheets:
0077
0078 http://www.st.com/web/en/resource/technical/document/datasheet/CD00157556.pdf
0079
0080 http://www.st.com/web/en/resource/technical/document/datasheet/CD00157558.pdf
0081
0082 http://www.st.com/web/en/resource/technical/document/datasheet/CD00266638.pdf
0083
0084 http://www.st.com/web/en/resource/technical/document/datasheet/CD00225278.pdf
0085
0086 http://www.st.com/web/en/resource/technical/document/datasheet/DM00076709.pdf
0087
0088 * JEDEC JC 42.4 compliant temperature sensor chips
0089
0090 Datasheet:
0091
0092 http://www.jedec.org/sites/default/files/docs/4_01_04R19.pdf
0093
0094
0095 Common for all chips:
0096
0097 Prefix: 'jc42'
0098
0099 Addresses scanned: I2C 0x18 - 0x1f
0100
0101 Author:
0102 Guenter Roeck <linux@roeck-us.net>
0103
0104
0105 Description
0106 -----------
0107
0108 This driver implements support for JEDEC JC 42.4 compliant temperature sensors,
0109 which are used on many DDR3 memory modules for mobile devices and servers. Some
0110 systems use the sensor to prevent memory overheating by automatically throttling
0111 the memory controller.
0112
0113 The driver auto-detects the chips listed above, but can be manually instantiated
0114 to support other JC 42.4 compliant chips.
0115
0116 Example: the following will load the driver for a generic JC 42.4 compliant
0117 temperature sensor at address 0x18 on I2C bus #1::
0118
0119 # modprobe jc42
0120 # echo jc42 0x18 > /sys/bus/i2c/devices/i2c-1/new_device
0121
0122 A JC 42.4 compliant chip supports a single temperature sensor. Minimum, maximum,
0123 and critical temperature can be configured. There are alarms for high, low,
0124 and critical thresholds.
0125
0126 There is also an hysteresis to control the thresholds for resetting alarms.
0127 Per JC 42.4 specification, the hysteresis threshold can be configured to 0, 1.5,
0128 3.0, and 6.0 degrees C. Configured hysteresis values will be rounded to those
0129 limits. The chip supports only a single register to configure the hysteresis,
0130 which applies to all limits. This register can be written by writing into
0131 temp1_crit_hyst. Other hysteresis attributes are read-only.
0132
0133 If the BIOS has configured the sensor for automatic temperature management, it
0134 is likely that it has locked the registers, i.e., that the temperature limits
0135 cannot be changed.
0136
0137 Sysfs entries
0138 -------------
0139
0140 ======================= ===========================================
0141 temp1_input Temperature (RO)
0142 temp1_min Minimum temperature (RO or RW)
0143 temp1_max Maximum temperature (RO or RW)
0144 temp1_crit Critical high temperature (RO or RW)
0145
0146 temp1_crit_hyst Critical hysteresis temperature (RO or RW)
0147 temp1_max_hyst Maximum hysteresis temperature (RO)
0148
0149 temp1_min_alarm Temperature low alarm
0150 temp1_max_alarm Temperature high alarm
0151 temp1_crit_alarm Temperature critical alarm
0152 ======================= ===========================================
