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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/Documentation/hwmon/lm75
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
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+Kernel driver lm75
+==================
+
+Supported chips:
+ * National Semiconductor LM75
+ Prefix: 'lm75'
+ Addresses scanned: I2C 0x48 - 0x4f
+ Datasheet: Publicly available at the National Semiconductor website
+ http://www.national.com/
+ * National Semiconductor LM75A
+ Prefix: 'lm75a'
+ Addresses scanned: I2C 0x48 - 0x4f
+ Datasheet: Publicly available at the National Semiconductor website
+ http://www.national.com/
+ * Dallas Semiconductor (now Maxim) DS75, DS1775, DS7505
+ Prefixes: 'ds75', 'ds1775', 'ds7505'
+ Addresses scanned: none
+ Datasheet: Publicly available at the Maxim website
+ http://www.maximintegrated.com/
+ * Maxim MAX6625, MAX6626
+ Prefixes: 'max6625', 'max6626'
+ Addresses scanned: none
+ Datasheet: Publicly available at the Maxim website
+ http://www.maxim-ic.com/
+ * Microchip (TelCom) TCN75
+ Prefix: 'tcn75'
+ Addresses scanned: none
+ Datasheet: Publicly available at the Microchip website
+ http://www.microchip.com/
+ * Microchip MCP9800, MCP9801, MCP9802, MCP9803
+ Prefix: 'mcp980x'
+ Addresses scanned: none
+ Datasheet: Publicly available at the Microchip website
+ http://www.microchip.com/
+ * Analog Devices ADT75
+ Prefix: 'adt75'
+ Addresses scanned: none
+ Datasheet: Publicly available at the Analog Devices website
+ http://www.analog.com/adt75
+ * ST Microelectronics STDS75
+ Prefix: 'stds75'
+ Addresses scanned: none
+ Datasheet: Publicly available at the ST website
+ http://www.st.com/internet/analog/product/121769.jsp
+ * Texas Instruments TMP100, TMP101, TMP105, TMP112, TMP75, TMP175, TMP275
+ Prefixes: 'tmp100', 'tmp101', 'tmp105', 'tmp112', 'tmp175', 'tmp75', 'tmp275'
+ Addresses scanned: none
+ Datasheet: Publicly available at the Texas Instruments website
+ http://www.ti.com/product/tmp100
+ http://www.ti.com/product/tmp101
+ http://www.ti.com/product/tmp105
+ http://www.ti.com/product/tmp112
+ http://www.ti.com/product/tmp75
+ http://www.ti.com/product/tmp175
+ http://www.ti.com/product/tmp275
+ * NXP LM75B
+ Prefix: 'lm75b'
+ Addresses scanned: none
+ Datasheet: Publicly available at the NXP website
+ http://www.nxp.com/documents/data_sheet/LM75B.pdf
+
+Author: Frodo Looijaard <frodol@dds.nl>
+
+Description
+-----------
+
+The LM75 implements one temperature sensor. Limits can be set through the
+Overtemperature Shutdown register and Hysteresis register. Each value can be
+set and read to half-degree accuracy.
+An alarm is issued (usually to a connected LM78) when the temperature
+gets higher then the Overtemperature Shutdown value; it stays on until
+the temperature falls below the Hysteresis value.
+All temperatures are in degrees Celsius, and are guaranteed within a
+range of -55 to +125 degrees.
+
+The driver caches the values for a period varying between 1 second for the
+slowest chips and 125 ms for the fastest chips; reading it more often
+will do no harm, but will return 'old' values.
+
+The original LM75 was typically used in combination with LM78-like chips
+on PC motherboards, to measure the temperature of the processor(s). Clones
+are now used in various embedded designs.
+
+The LM75 is essentially an industry standard; there may be other
+LM75 clones not listed here, with or without various enhancements,
+that are supported. The clones are not detected by the driver, unless
+they reproduce the exact register tricks of the original LM75, and must
+therefore be instantiated explicitly. Higher resolution up to 12-bit
+is supported by this driver, other specific enhancements are not.
+
+The LM77 is not supported, contrary to what we pretended for a long time.
+Both chips are simply not compatible, value encoding differs.