|author||Linus Torvalds <email@example.com>||2005-04-16 15:20:36 -0700|
|committer||Linus Torvalds <firstname.lastname@example.org>||2005-04-16 15:20:36 -0700|
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
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+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.
+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.
+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
+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.
+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.
+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.
+If you spam it hard enough, printk can be lossy. This module really wants
+something like relayfs.