On 11/19/2018 03:43 PM, Boris Brezillon wrote: > On Mon, 19 Nov 2018 15:14:07 +0100 > Marek Vasut <marek.vasut@xxxxxxxxx> wrote: > >> On 11/19/2018 03:10 PM, Boris Brezillon wrote: >>> On Mon, 19 Nov 2018 14:49:31 +0100 >>> Marek Vasut <marek.vasut@xxxxxxxxx> wrote: >>> >>>> On 11/19/2018 11:01 AM, Mason Yang wrote: >>>>> Document the bindings used by the Renesas R-Car D3 RPC controller. >>>>> >>>>> Signed-off-by: Mason Yang <masonccyang@xxxxxxxxxxx> >>>>> --- >>>>> .../devicetree/bindings/spi/spi-renesas-rpc.txt | 33 ++++++++++++++++++++++ >>>>> 1 file changed, 33 insertions(+) >>>>> create mode 100644 Documentation/devicetree/bindings/spi/spi-renesas-rpc.txt >>>>> >>>>> diff --git a/Documentation/devicetree/bindings/spi/spi-renesas-rpc.txt b/Documentation/devicetree/bindings/spi/spi-renesas-rpc.txt >>>>> new file mode 100644 >>>>> index 0000000..8286cc8 >>>>> --- /dev/null >>>>> +++ b/Documentation/devicetree/bindings/spi/spi-renesas-rpc.txt >>>>> @@ -0,0 +1,33 @@ >>>>> +Renesas R-Car D3 RPC controller Device Tree Bindings >>>>> +---------------------------------------------------- >>>>> + >>>>> +Required properties: >>>>> +- compatible: should be "renesas,rpc-r8a77995" >>>>> +- #address-cells: should be 1 >>>>> +- #size-cells: should be 0 >>>>> +- reg: should contain 2 entries, one for the registers and one for the direct >>>>> + mapping area >>>>> +- reg-names: should contain "rpc_regs" and "dirmap" >>>>> +- interrupts: interrupt line connected to the RPC SPI controller >>>> >>>> Do you also plan to support the RPC HF mode ? And if so, how would that >>>> look in the bindings ? >>> >>> Not sure this approach is still accepted, but that's how we solved the >>> problem for the flexcom block [1]. >>> >>> [1]https://elixir.bootlin.com/linux/v4.20-rc3/source/Documentation/devicetree/bindings/mfd/atmel-flexcom.txt >> >> That looks pretty horrible. >> >> In U-Boot we check whether the device hanging under the controller node >> is JEDEC SPI flash or CFI flash and based on that decide what the config >> of the controller should be (SPI or HF). Not sure that's much better,but >> at least it doesn't need extra nodes which do not really represent any >> kind of real hardware. >> > > The subnodes are not needed, you can just have a property that tells in > which mode the controller is supposed to operate, and the MFD would > create a sub-device that points to the same device_node. Do you even need a dedicated property ? I think you can decide purely on what node is hanging under the controller (jedec spi nor or cfi nor). > Or we can have > a single driver that decides what to declare (a spi_controller or flash > controller), but you'd still have to decide where to place this > driver... I'd definitely prefer a single driver. -- Best regards, Marek Vasut
