[PATCH 1/2] ARM: dts: r8a7793: add CAN clocks

Simon Horman horms+renesas at verge.net.au
Wed Jan 20 21:09:40 PST 2016


The R-Car CAN controllers can derive the CAN bus clock not only from their
peripheral clock input (clkp1) but also from the other internal clock
(clkp2) and external clock fed on CAN_CLK pin. Describe those clocks in
the device tree along with  the USB_EXTAL clock from which clkp2 is
derived.

Based on work by Sergei Shtylyov for the r8a7791 SoC.

Cc: Sergei Shtylyov <sergei.shtylyov at cogentembedded.com>
Signed-off-by: Simon Horman <horms+renesas at verge.net.au>
---
 arch/arm/boot/dts/r8a7793.dtsi | 20 +++++++++++++++++++-
 1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/r8a7793.dtsi b/arch/arm/boot/dts/r8a7793.dtsi
index 0ce7cc420c9d..5d9375fa6759 100644
--- a/arch/arm/boot/dts/r8a7793.dtsi
+++ b/arch/arm/boot/dts/r8a7793.dtsi
@@ -706,12 +706,30 @@
 			clock-output-names = "extal";
 		};
 
+		/* External USB clock - can be overridden by the board */
+		usb_extal_clk: usb_extal_clk {
+			compatible = "fixed-clock";
+			#clock-cells = <0>;
+			clock-frequency = <48000000>;
+			clock-output-names = "usb_extal";
+		};
+
+		/* External CAN clock */
+		can_clk: can_clk {
+			compatible = "fixed-clock";
+			#clock-cells = <0>;
+			/* This value must be overridden by the board. */
+			clock-frequency = <0>;
+			clock-output-names = "can_clk";
+			status = "disabled";
+		};
+
 		/* Special CPG clocks */
 		cpg_clocks: cpg_clocks at e6150000 {
 			compatible = "renesas,r8a7793-cpg-clocks",
 				     "renesas,rcar-gen2-cpg-clocks";
 			reg = <0 0xe6150000 0 0x1000>;
-			clocks = <&extal_clk>;
+			clocks = <&extal_clk &usb_extal_clk>;
 			#clock-cells = <1>;
 			clock-output-names = "main", "pll0", "pll1", "pll3",
 					     "lb", "qspi", "sdh", "sd0", "z",
-- 
2.1.4




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