can: rcar_can: Add r8a7795 support

Added r8a7795 SoC support.

Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

Documentation/devicetree/bindings/net/can/rcar_can.txt

@@ -9,8 +9,10 @@ Required properties:
 	      "renesas,can-r8a7792" if CAN controller is a part of R8A7792 SoC.
 	      "renesas,can-r8a7793" if CAN controller is a part of R8A7793 SoC.
 	      "renesas,can-r8a7794" if CAN controller is a part of R8A7794 SoC.
+	      "renesas,can-r8a7795" if CAN controller is a part of R8A7795 SoC.
 	      "renesas,rcar-gen1-can" for a generic R-Car Gen1 compatible device.
 	      "renesas,rcar-gen2-can" for a generic R-Car Gen2 compatible device.
+	      "renesas,rcar-gen3-can" for a generic R-Car Gen3 compatible device.
 	      When compatible with the generic version, nodes must list the
 	      SoC-specific version corresponding to the platform first
 	      followed by the generic version.
@@ -22,6 +24,15 @@ Required properties:
 - pinctrl-0: pin control group to be used for this controller.
 - pinctrl-names: must be "default".
 
+Required properties for "renesas,can-r8a7795" compatible:
+In R8A7795 SoC, "clkp2" can be CANFD clock. This is a div6 clock and can be
+used by both CAN and CAN FD controller at the same time. It needs to be scaled
+to maximum frequency if any of these controllers use it. This is done using
+the below properties.
+
+- assigned-clocks: phandle of clkp2(CANFD) clock.
+- assigned-clock-rates: maximum frequency of this clock.
+
 Optional properties:
 - renesas,can-clock-select: R-Car CAN Clock Source Select. Valid values are:
 			    <0x0> (default) : Peripheral clock (clkp1)

drivers/net/can/Kconfig

@@ -106,7 +106,7 @@ config CAN_JANZ_ICAN3
 
 config CAN_RCAR
 	tristate "Renesas R-Car CAN controller"
-	depends on ARM
+	depends on ARCH_RENESAS || ARM
 	---help---
 	  Say Y here if you want to use CAN controller found on Renesas R-Car
 	  SoCs.

drivers/net/can/rcar_can.c

@@ -906,6 +906,7 @@ static const struct of_device_id rcar_can_of_table[] __maybe_unused = {
 	{ .compatible = "renesas,can-r8a7791" },
 	{ .compatible = "renesas,rcar-gen1-can" },
 	{ .compatible = "renesas,rcar-gen2-can" },
+	{ .compatible = "renesas,rcar-gen3-can" },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, rcar_can_of_table);