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authorDavid S. Miller <davem@davemloft.net>2010-03-15 23:23:54 (GMT)
committerDavid S. Miller <davem@davemloft.net>2010-03-15 23:23:54 (GMT)
commit4961e02f1999e1c3468c09b2669c94d7c3ae82a8 (patch)
tree44c15abb09d7ba5e17a9aba95ee246648b1c1a8a /Documentation/i2c/smbus-protocol
parentd14a0ebda7d3daede1a99c01527affb9ceaa4c22 (diff)
parenta3d3203e4bb40f253b1541e310dc0f9305be7c84 (diff)
downloadlinux-fsl-qoriq-4961e02f1999e1c3468c09b2669c94d7c3ae82a8.tar.xz
Merge branch 'master' of /home/davem/src/GIT/linux-2.6/
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+++ b/Documentation/i2c/smbus-protocol
@@ -185,6 +185,22 @@ the protocol. All ARP communications use slave address 0x61 and
require PEC checksums.
+SMBus Alert
+===========
+
+SMBus Alert was introduced in Revision 1.0 of the specification.
+
+The SMBus alert protocol allows several SMBus slave devices to share a
+single interrupt pin on the SMBus master, while still allowing the master
+to know which slave triggered the interrupt.
+
+This is implemented the following way in the Linux kernel:
+* I2C bus drivers which support SMBus alert should call
+ i2c_setup_smbus_alert() to setup SMBus alert support.
+* I2C drivers for devices which can trigger SMBus alerts should implement
+ the optional alert() callback.
+
+
I2C Block Transactions
======================