i2c-ocores: add some device tree documentation

This puts some documentation for the device tree configuration at the head
of the driver file.  Hopefully this can get moved to a common area for this
type of documentation at a later date; unfortunately, there isn't really
such a place in the kernel tree at this time.

Furthermore, the regstep and clock-frequency parameters are really bus
parameters and should probably be passed to the driver in a better way.
Consider that a TODO.

Signed-off-by: Jonas Bonn <jonas@southpole.se>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
This commit is contained in:
Jonas Bonn 2010-11-24 17:26:22 +01:00 committed by Ben Dooks
parent 47def5b80f
commit d9240e612b

View File

@ -9,6 +9,41 @@
* kind, whether express or implied.
*/
/*
* Device tree configuration:
*
* Required properties:
* - compatible : "opencores,i2c-ocores"
* - reg : bus address start and address range size of device
* - interrupts : interrupt number
* - regstep : size of device registers in bytes
* - clock-frequency : frequency of bus clock in Hz
*
* Example:
*
* i2c0: ocores@a0000000 {
* compatible = "opencores,i2c-ocores";
* reg = <0xa0000000 0x8>;
* interrupts = <10>;
*
* regstep = <1>;
* clock-frequency = <20000000>;
*
* -- Devices connected on this I2C bus get
* -- defined here; address- and size-cells
* -- apply to these child devices
*
* #address-cells = <1>;
* #size-cells = <0>;
*
* dummy@60 {
* compatible = "dummy";
* reg = <60>;
* };
* };
*
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>