X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=Documentation%2Fi2c%2Fi2c-stub;h=9cc081e697648ecb3feaadddcc4b8da187294db9;hb=refs%2Fheads%2Fvserver;hp=2626ba926e4db8c943be86e6efe018440e11a4fc;hpb=87fc8d1bb10cd459024a742c6a10961fefcef18f;p=linux-2.6.git

diff --git a/Documentation/i2c/i2c-stub b/Documentation/i2c/i2c-stub
index 2626ba926..9cc081e69 100644
--- a/Documentation/i2c/i2c-stub
+++ b/Documentation/i2c/i2c-stub
@@ -2,20 +2,33 @@ MODULE: i2c-stub
 
 DESCRIPTION:
 
-This module is a very simple fake I2C/SMBus driver.  It implements three
-types of SMBus commands: write quick, (r/w) byte data, and (r/w) word data.
+This module is a very simple fake I2C/SMBus driver.  It implements four
+types of SMBus commands: write quick, (r/w) byte, (r/w) byte data, and
+(r/w) word data.
+
+You need to provide a chip address as a module parameter when loading
+this driver, which will then only react to SMBus commands to this address.
 
 No hardware is needed nor associated with this module.  It will accept write
-quick commands to all addresses; it will respond to the other commands (also
-to all addresses) by reading from or writing to an array in memory.  It will
+quick commands to one address; it will respond to the other commands (also
+to one address) by reading from or writing to an array in memory.  It will
 also spam the kernel logs for every command it handles.
 
+A pointer register with auto-increment is implemented for all byte
+operations.  This allows for continuous byte reads like those supported by
+EEPROMs, among others.
+
 The typical use-case is like this:
 	1. load this module
 	2. use i2cset (from lm_sensors project) to pre-load some data
 	3. load the target sensors chip driver module
 	4. observe its behavior in the kernel log
 
+PARAMETERS:
+
+int chip_addr:
+	The SMBus address to emulate a chip at.
+
 CAVEATS:
 
 There are independent arrays for byte/data and word/data commands.  Depending
@@ -28,6 +41,9 @@ If the hardware for your driver has banked registers (e.g. Winbond sensors
 chips) this module will not work well - although it could be extended to
 support that pretty easily.
 
+Only one chip address is supported - although this module could be
+extended to support more.
+
 If you spam it hard enough, printk can be lossy.  This module really wants
 something like relayfs.