1Kernel driver jc42
2==================
3
4Supported chips:
5  * Analog Devices ADT7408
6    Prefix: 'adt7408'
7    Addresses scanned: I2C 0x18 - 0x1f
8    Datasheets:
9	http://www.analog.com/static/imported-files/data_sheets/ADT7408.pdf
10  * IDT TSE2002B3, TS3000B3
11    Prefix: 'tse2002b3', 'ts3000b3'
12    Addresses scanned: I2C 0x18 - 0x1f
13    Datasheets:
14	http://www.idt.com/products/getdoc.cfm?docid=18715691
15	http://www.idt.com/products/getdoc.cfm?docid=18715692
16  * Maxim MAX6604
17    Prefix: 'max6604'
18    Addresses scanned: I2C 0x18 - 0x1f
19    Datasheets:
20	http://datasheets.maxim-ic.com/en/ds/MAX6604.pdf
21  * Microchip MCP9805, MCP98242, MCP98243, MCP9843
22    Prefixes: 'mcp9805', 'mcp98242', 'mcp98243', 'mcp9843'
23    Addresses scanned: I2C 0x18 - 0x1f
24    Datasheets:
25	http://ww1.microchip.com/downloads/en/DeviceDoc/21977b.pdf
26	http://ww1.microchip.com/downloads/en/DeviceDoc/21996a.pdf
27	http://ww1.microchip.com/downloads/en/DeviceDoc/22153c.pdf
28  * NXP Semiconductors SE97, SE97B
29    Prefix: 'se97'
30    Addresses scanned: I2C 0x18 - 0x1f
31    Datasheets:
32	http://www.nxp.com/documents/data_sheet/SE97.pdf
33	http://www.nxp.com/documents/data_sheet/SE97B.pdf
34  * NXP Semiconductors SE98
35    Prefix: 'se98'
36    Addresses scanned: I2C 0x18 - 0x1f
37    Datasheets:
38	http://www.nxp.com/documents/data_sheet/SE98.pdf
39  * ON Semiconductor CAT34TS02, CAT6095
40    Prefix: 'cat34ts02', 'cat6095'
41    Addresses scanned: I2C 0x18 - 0x1f
42    Datasheet:
43	http://www.onsemi.com/pub_link/Collateral/CAT34TS02-D.PDF
44	http://www.onsemi.com/pub/Collateral/CAT6095-D.PDF
45  * ST Microelectronics STTS424, STTS424E02
46    Prefix: 'stts424'
47    Addresses scanned: I2C 0x18 - 0x1f
48    Datasheets:
49	http://www.st.com/stonline/products/literature/ds/13447/stts424.pdf
50	http://www.st.com/stonline/products/literature/ds/13448/stts424e02.pdf
51  * JEDEC JC 42.4 compliant temperature sensor chips
52    Prefix: 'jc42'
53    Addresses scanned: I2C 0x18 - 0x1f
54    Datasheet:
55	http://www.jedec.org/sites/default/files/docs/4_01_04R19.pdf
56
57Author:
58	Guenter Roeck <guenter.roeck@ericsson.com>
59
60
61Description
62-----------
63
64This driver implements support for JEDEC JC 42.4 compliant temperature sensors,
65which are used on many DDR3 memory modules for mobile devices and servers. Some
66systems use the sensor to prevent memory overheating by automatically throttling
67the memory controller.
68
69The driver auto-detects the chips listed above, but can be manually instantiated
70to support other JC 42.4 compliant chips.
71
72Example: the following will load the driver for a generic JC 42.4 compliant
73temperature sensor at address 0x18 on I2C bus #1:
74
75# modprobe jc42
76# echo jc42 0x18 > /sys/bus/i2c/devices/i2c-1/new_device
77
78A JC 42.4 compliant chip supports a single temperature sensor. Minimum, maximum,
79and critical temperature can be configured. There are alarms for high, low,
80and critical thresholds.
81
82There is also an hysteresis to control the thresholds for resetting alarms.
83Per JC 42.4 specification, the hysteresis threshold can be configured to 0, 1.5,
843.0, and 6.0 degrees C. Configured hysteresis values will be rounded to those
85limits. The chip supports only a single register to configure the hysteresis,
86which applies to all limits. This register can be written by writing into
87temp1_crit_hyst. Other hysteresis attributes are read-only.
88
89If the BIOS has configured the sensor for automatic temperature management, it
90is likely that it has locked the registers, i.e., that the temperature limits
91cannot be changed.
92
93Sysfs entries
94-------------
95
96temp1_input		Temperature (RO)
97temp1_min		Minimum temperature (RO or RW)
98temp1_max		Maximum temperature (RO or RW)
99temp1_crit		Critical high temperature (RO or RW)
100
101temp1_crit_hyst		Critical hysteresis temperature (RO or RW)
102temp1_max_hyst		Maximum hysteresis temperature (RO)
103
104temp1_min_alarm		Temperature low alarm
105temp1_max_alarm		Temperature high alarm
106temp1_crit_alarm	Temperature critical alarm
107