From 4453d7364d3b1f92475f104d4625abee36a7733d Mon Sep 17 00:00:00 2001 From: Guenter Roeck Date: Mon, 9 Aug 2010 17:21:08 -0700 Subject: hwmon: add support for JEDEC JC 42.4 compliant temperature sensors [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Guenter Roeck Cc: Jean Delvare Cc: Randy Dunlap Cc: Hans de Goede Cc: Mark Brown Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/hwmon/jc42 | 97 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 97 insertions(+) create mode 100644 Documentation/hwmon/jc42 (limited to 'Documentation') diff --git a/Documentation/hwmon/jc42 b/Documentation/hwmon/jc42 new file mode 100644 index 0000000..0e76ef1 --- /dev/null +++ b/Documentation/hwmon/jc42 @@ -0,0 +1,97 @@ +Kernel driver jc42 +================== + +Supported chips: + * Analog Devices ADT7408 + Prefix: 'adt7408' + Addresses scanned: I2C 0x18 - 0x1f + Datasheets: + http://www.analog.com/static/imported-files/data_sheets/ADT7408.pdf + * IDT TSE2002B3, TS3000B3 + Prefix: 'tse2002b3', 'ts3000b3' + Addresses scanned: I2C 0x18 - 0x1f + Datasheets: + http://www.idt.com/products/getdoc.cfm?docid=18715691 + http://www.idt.com/products/getdoc.cfm?docid=18715692 + * Maxim MAX6604 + Prefix: 'max6604' + Addresses scanned: I2C 0x18 - 0x1f + Datasheets: + http://datasheets.maxim-ic.com/en/ds/MAX6604.pdf + * Microchip MCP9805, MCP98242, MCP98243, MCP9843 + Prefixes: 'mcp9805', 'mcp98242', 'mcp98243', 'mcp9843' + Addresses scanned: I2C 0x18 - 0x1f + Datasheets: + http://ww1.microchip.com/downloads/en/DeviceDoc/21977b.pdf + http://ww1.microchip.com/downloads/en/DeviceDoc/21996a.pdf + http://ww1.microchip.com/downloads/en/DeviceDoc/22153c.pdf + * NXP Semiconductors SE97, SE97B + Prefix: 'se97' + Addresses scanned: I2C 0x18 - 0x1f + Datasheets: + http://www.nxp.com/documents/data_sheet/SE97.pdf + http://www.nxp.com/documents/data_sheet/SE97B.pdf + * NXP Semiconductors SE98 + Prefix: 'se98' + Addresses scanned: I2C 0x18 - 0x1f + Datasheets: + http://www.nxp.com/documents/data_sheet/SE98.pdf + * ON Semiconductor CAT34TS02, CAT6095 + Prefix: 'cat34ts02', 'cat6095' + Addresses scanned: I2C 0x18 - 0x1f + Datasheet: + http://www.onsemi.com/pub_link/Collateral/CAT34TS02-D.PDF + http://www.onsemi.com/pub/Collateral/CAT6095-D.PDF + * ST Microelectronics STTS424, STTS424E02 + Prefix: 'stts424' + Addresses scanned: I2C 0x18 - 0x1f + Datasheets: + http://www.st.com/stonline/products/literature/ds/13447/stts424.pdf + http://www.st.com/stonline/products/literature/ds/13448/stts424e02.pdf + * JEDEC JC 42.4 compliant temperature sensor chips + Prefix: 'jc42' + Addresses scanned: I2C 0x18 - 0x1f + Datasheet: - + +Author: + Guenter Roeck + + +Description +----------- + +This driver implements support for JEDEC JC 42.4 compliant temperature sensors. +The driver auto-detects the chips listed above, but can be manually instantiated +to support other JC 42.4 compliant chips. + +Example: the following will load the driver for a generic JC 42.4 compliant +temperature sensor at address 0x18 on I2C bus #1: + +# modprobe jc42 +# echo jc42 0x18 > /sys/bus/i2c/devices/i2c-1/new_device + +A JC 42.4 compliant chip supports a single temperature sensor. Minimum, maximum, +and critical temperature can be configured. There are alarms for high, low, +and critical thresholds. + +There is also an hysteresis to control the thresholds for resetting alarms. +Per JC 42.4 specification, the hysteresis threshold can be configured to 0, 1.5, +3.0, and 6.0 degrees C. Configured hysteresis values will be rounded to those +limits. The chip supports only a single register to configure the hysteresis, +which applies to all limits. This register can be written by writing into +temp1_crit_hyst. Other hysteresis attributes are read-only. + +Sysfs entries +------------- + +temp1_input Temperature (RO) +temp1_min Minimum temperature (RW) +temp1_max Maximum temperature (RW) +temp1_crit Critical high temperature (RW) + +temp1_crit_hyst Critical hysteresis temperature (RW) +temp1_max_hyst Maximum hysteresis temperature (RO) + +temp1_min_alarm Temperature low alarm +temp1_max_alarm Temperature high alarm +temp1_crit_alarm Temperature critical alarm -- cgit v1.1