ARM: OMAP: Add documentation for function omap_register_i2c_bus

Signed-off-by: Jarkko Nikula <jarkko.nikula@nokia.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/plat-omap/i2c.c

@@ -119,6 +119,15 @@ static void __init omap_i2c_mux_pins(int bus)
 	omap_cfg_reg(scl);
 }
 
+/**
+ * omap_register_i2c_bus - register I2C bus with device descriptors
+ * @bus_id: bus id counting from number 1
+ * @clkrate: clock rate of the bus in kHz
+ * @info: pointer into I2C device descriptor table or NULL
+ * @len: number of descriptors in the table
+ *
+ * Returns 0 on success or an error code.
+ */
 int __init omap_register_i2c_bus(int bus_id, u32 clkrate,
 			  struct i2c_board_info const *info,
 			  unsigned len)