X-Git-Url: https://git.karo-electronics.de/?a=blobdiff_plain;f=Documentation%2Fi2c%2Fi2c-stub;h=0d8be1c20c16b6bf96a95f42e7855d635e3a32b8;hb=76b3e28fa728bb68895cbd8375f5ce233bd891de;hp=d6dcb138abf510534d2539665f74176c013a37b4;hpb=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2;p=mv-sheeva.git

diff --git a/Documentation/i2c/i2c-stub b/Documentation/i2c/i2c-stub
index d6dcb138abf..0d8be1c20c1 100644
--- a/Documentation/i2c/i2c-stub
+++ b/Documentation/i2c/i2c-stub
@@ -6,10 +6,14 @@ 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 chip addresses as a module parameter when loading this
+driver, which will then only react to SMBus commands to these addresses.
+
 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
-also spam the kernel logs for every command it handles.
+quick commands to the specified addresses; it will respond to the other
+commands (also to the specified addresses) by reading from or writing to
+arrays 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
@@ -21,10 +25,15 @@ The typical use-case is like this:
 	3. load the target sensors chip driver module
 	4. observe its behavior in the kernel log
 
-CAVEATS:
+There's a script named i2c-stub-from-dump in the i2c-tools package which
+can load register values automatically from a chip dump.
+
+PARAMETERS:
 
-There are independent arrays for byte/data and word/data commands.  Depending
-on if/how a target driver mixes them, you'll need to be careful.
+int chip_addr[10]:
+	The SMBus addresses to emulate chips at.
+
+CAVEATS:
 
 If your target driver polls some byte or word waiting for it to change, the
 stub could lock it up.  Use i2cset to unlock it.