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authorNeil Horman <nhorman@tuxdriver.com>2013-02-04 23:54:10 +0400
committerWolfram Sang <wolfram@the-dreams.de>2013-02-10 22:55:25 +0400
commit13f35ac14cd0a9a1c4f0034c4c40d0ae98844ce9 (patch)
tree18b98cd3edcbb66466e765fbb898640687fb4e52 /Documentation/i2c
parente789029761503f0cce03e8767a56ae099b88e1bd (diff)
downloadlinux-13f35ac14cd0a9a1c4f0034c4c40d0ae98844ce9.tar.xz
i2c: Adding support for Intel iSMT SMBus 2.0 host controller
The iSMT (Intel SMBus Message Transport) supports multi-master I2C/SMBus, as well as IPMI. It's operation is DMA-based and utilizes descriptors to initiate transactions on the bus. The iSMT hardware can act as both a master and a target, although this driver only supports being a master. Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: Bill Brown <bill.e.brown@intel.com> Tested-by: Seth Heasley <seth.heasley@intel.com> Reviewed-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Wolfram Sang <wolfram@the-dreams.de>
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+Kernel driver i2c-ismt
+
+Supported adapters:
+ * Intel S12xx series SOCs
+
+Authors:
+ Bill Brown <bill.e.brown@intel.com>
+
+
+Module Parameters
+-----------------
+
+* bus_speed (unsigned int)
+Allows changing of the bus speed. Normally, the bus speed is set by the BIOS
+and never needs to be changed. However, some SMBus analyzers are too slow for
+monitoring the bus during debug, thus the need for this module parameter.
+Specify the bus speed in kHz.
+Available bus frequency settings:
+ 0 no change
+ 80 kHz
+ 100 kHz
+ 400 kHz
+ 1000 kHz
+
+
+Description
+-----------
+
+The S12xx series of SOCs have a pair of integrated SMBus 2.0 controllers
+targeted primarily at the microserver and storage markets.
+
+The S12xx series contain a pair of PCI functions. An output of lspci will show
+something similar to the following:
+
+ 00:13.0 System peripheral: Intel Corporation Centerton SMBus 2.0 Controller 0
+ 00:13.1 System peripheral: Intel Corporation Centerton SMBus 2.0 Controller 1