i2c-stub: Allow user to disable some commands

Add a module parameter to override the functionality bitfield. This
lets the user disable some commands. This can be used to force a chip
driver to take different code paths.

Signed-off-by: Jean Delvare <khali@linux-fr.org>

1 files changed, 6 insertions, 0 deletions

diff --git a/Documentation/i2c/i2c-stub b/Documentation/i2c/i2c-stub
index d9c383b30925..326d1ee81e0e 100644
--- a/Documentation/i2c/i2c-stub
+++ b/Documentation/i2c/i2c-stub
@@ -33,6 +33,12 @@ PARAMETERS:
 int chip_addr[10]:
         The SMBus addresses to emulate chips at.
 
+unsigned long functionality:
+        Functionality override, to disable some commands. See I2C_FUNC_*
+        constants in <linux/i2c.h> for the suitable values. For example,
+        value 0x1f0000 would only enable the quick, byte and byte data
+        commands.
+
 CAVEATS:
 
 If your target driver polls some byte or word waiting for it to change, the