Subject: Re: [PATCH] rcar_can: add device tree support

From: Sergei Shtylyov <[email-masked]>
Date: Thu, 03 Jul 2014 00:26:07 +0400

Hello.

On 07/02/2014 02:14 PM, Mark Rutland wrote:

>>> Add support of the device tree probing for the Renesas R-Car CAN controllers
>>> documenting the device tree bindings as necessary.

[...]

>>> Signed-off-by: Sergei Shtylyov <[email-masked]>

[...]

>>> Index: net-next/Documentation/devicetree/bindings/net/can/rcar_can.txt
>>> ===================================================================
>>> --- /dev/null
>>> +++ net-next/Documentation/devicetree/bindings/net/can/rcar_can.txt
>>> @@ -0,0 +1,40 @@
[...]

>>> +- reg: physical base address and size of the R-Car CAN register map.
>>> +- interrupts: interrupt specifier for the sole interrupt.
>>> +- clocks: phandle and clock specifier for the R-Car CAN clock input.
>>> +- pinctrl-0: pin control group to be used for this controller.
>>> +- pinctrl-names: must be "default".
>>> +
>>> +Optional properties:
>>> +- clock-select: R-Car CAN Clock Source Select. Valid values are:
>>> +		<0x0> (default) : Peripheral clock (clkp1)
>>> +		<0x1> : Peripheral clock (clkp2)
>>> +		<0x3> : Externally input clock

> What's this for, and how does this interact with the single clock listed
> above?

    That's supposed to select a source for the CAN bus clock. Looking back at 
the driver, it seems to actually only support the value of 0. That's something 
we haven't given enough attention to clearly... :-/

> THanks,
> Mark.

WBR, Sergei