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Based on kernel version 3.9. Page generated on 2013-05-02 23:07 EST.

1	Kernel driver jc42
2	==================
3	
4	Supported 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	
51	Author:
52		Guenter Roeck <linux@roeck-us.net>
53	
54	
55	Description
56	-----------
57	
58	This driver implements support for JEDEC JC 42.4 compliant temperature sensors,
59	which are used on many DDR3 memory modules for mobile devices and servers. Some
60	systems use the sensor to prevent memory overheating by automatically throttling
61	the memory controller.
62	
63	The driver auto-detects the chips listed above, but can be manually instantiated
64	to support other JC 42.4 compliant chips.
65	
66	Example: the following will load the driver for a generic JC 42.4 compliant
67	temperature 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	
72	A JC 42.4 compliant chip supports a single temperature sensor. Minimum, maximum,
73	and critical temperature can be configured. There are alarms for high, low,
74	and critical thresholds.
75	
76	There is also an hysteresis to control the thresholds for resetting alarms.
77	Per JC 42.4 specification, the hysteresis threshold can be configured to 0, 1.5,
78	3.0, and 6.0 degrees C. Configured hysteresis values will be rounded to those
79	limits. The chip supports only a single register to configure the hysteresis,
80	which applies to all limits. This register can be written by writing into
81	temp1_crit_hyst. Other hysteresis attributes are read-only.
82	
83	If the BIOS has configured the sensor for automatic temperature management, it
84	is likely that it has locked the registers, i.e., that the temperature limits
85	cannot be changed.
86	
87	Sysfs entries
88	-------------
89	
90	temp1_input		Temperature (RO)
91	temp1_min		Minimum temperature (RO or RW)
92	temp1_max		Maximum temperature (RO or RW)
93	temp1_crit		Critical high temperature (RO or RW)
94	
95	temp1_crit_hyst		Critical hysteresis temperature (RO or RW)
96	temp1_max_hyst		Maximum hysteresis temperature (RO)
97	
98	temp1_min_alarm		Temperature low alarm
99	temp1_max_alarm		Temperature high alarm
100	temp1_crit_alarm	Temperature critical alarm
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