[PATCH] arm64: dts: renesas: sparrow-hawk: Add overlay for WaveShare 2CH CANFD HAT
Marek Vasut
marek.vasut+renesas at mailbox.org
Fri Aug 7 19:56:26 PDT 2026
Add a DT overlay to bind the WaveShare 2-Channel Isolated CAN FD
Expansion HAT on the Retronix R-Car V4H Sparrow Hawk board.
Current device link is at https://www.waveshare.com/2-ch-can-fd-hat.htm
Signed-off-by: Marek Vasut <marek.vasut+renesas at mailbox.org>
---
Cc: Conor Dooley <conor+dt at kernel.org>
Cc: Geert Uytterhoeven <geert+renesas at glider.be>
Cc: Krzysztof Kozlowski <krzk+dt at kernel.org>
Cc: Magnus Damm <magnus.damm at gmail.com>
Cc: Rob Herring <robh at kernel.org>
Cc: devicetree at vger.kernel.org
Cc: linux-kernel at vger.kernel.org
Cc: linux-renesas-soc at vger.kernel.org
---
arch/arm64/boot/dts/renesas/Makefile | 3 +
.../r8a779g3-sparrow-hawk-ws-2ch-canfd.dtso | 130 ++++++++++++++++++
2 files changed, 133 insertions(+)
create mode 100644 arch/arm64/boot/dts/renesas/r8a779g3-sparrow-hawk-ws-2ch-canfd.dtso
diff --git a/arch/arm64/boot/dts/renesas/Makefile b/arch/arm64/boot/dts/renesas/Makefile
index 8bf155badd111..69c1405a6fd01 100644
--- a/arch/arm64/boot/dts/renesas/Makefile
+++ b/arch/arm64/boot/dts/renesas/Makefile
@@ -124,6 +124,9 @@ dtb-$(CONFIG_ARCH_R8A779G0) += r8a779g3-sparrow-hawk-rpi-display-2-5in.dtb
dtb-$(CONFIG_ARCH_R8A779G0) += r8a779g3-sparrow-hawk-rpi-display-2-7in.dtbo
r8a779g3-sparrow-hawk-rpi-display-2-7in-dtbs := r8a779g3-sparrow-hawk.dtb r8a779g3-sparrow-hawk-rpi-display-2-7in.dtbo
dtb-$(CONFIG_ARCH_R8A779G0) += r8a779g3-sparrow-hawk-rpi-display-2-7in.dtb
+dtb-$(CONFIG_ARCH_R8A779G0) += r8a779g3-sparrow-hawk-ws-2ch-canfd.dtbo
+r8a779g3-sparrow-hawk-ws-2ch-canfd-dtbs := r8a779g3-sparrow-hawk.dtb r8a779g3-sparrow-hawk-ws-2ch-canfd.dtbo
+dtb-$(CONFIG_ARCH_R8A779G0) += r8a779g3-sparrow-hawk-ws-2ch-canfd.dtb
dtb-$(CONFIG_ARCH_R8A779G0) += r8a779g3-sparrow-hawk-ws-display-13in.dtbo
r8a779g3-sparrow-hawk-ws-display-13in-dtbs := r8a779g3-sparrow-hawk.dtb r8a779g3-sparrow-hawk-ws-display-13in.dtbo
dtb-$(CONFIG_ARCH_R8A779G0) += r8a779g3-sparrow-hawk-ws-display-13in.dtb
diff --git a/arch/arm64/boot/dts/renesas/r8a779g3-sparrow-hawk-ws-2ch-canfd.dtso b/arch/arm64/boot/dts/renesas/r8a779g3-sparrow-hawk-ws-2ch-canfd.dtso
new file mode 100644
index 0000000000000..de72680efa7c6
--- /dev/null
+++ b/arch/arm64/boot/dts/renesas/r8a779g3-sparrow-hawk-ws-2ch-canfd.dtso
@@ -0,0 +1,130 @@
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+/*
+ * Device Tree Overlay for the Waveshare 2-Channel Isolated CAN FD HAT
+ * on connector CN7 on R-Car V4H ES3.0 Sparrow Hawk board
+ *
+ * Copyright (C) 2026 Marek Vasut <marek.vasut+renesas at mailbox.org>
+ *
+ * Example usage:
+ * - Connect HAT signals to Sparrow Hawk board CAN BUS connector CONN2:
+ * HAT CAN_0 H -- CONN2 pin 6
+ * HAT CAN_0 L -- CONN2 pin 2
+ * HAT CAN_1 H -- CONN2 pin 5
+ * HAT CAN_1 L -- CONN2 pin 1
+ *
+ * - Determine which interface is which:
+ * $ ip -d link show
+ * 2: can0: <NOARP,ECHO> ...
+ * ...
+ * clock 40000000 ... e6660000.can <------ Native Renesas CANFD
+ * 3: can1: <NOARP,ECHO> ...
+ * ...
+ * 4: can2: <NOARP,ECHO> ...
+ * ...
+ * clock 40000000 ... spi1.0 <------------ SPI CANFD on this HAT
+ * 5: can3: <NOARP,ECHO> ...
+ * ...
+ *
+ * - Bring connected interfaces up:
+ * # CAN_0 link
+ * $ ip link set can0 up type can bitrate 125000 dbitrate 250000 fd on
+ * $ ip link set can3 up type can bitrate 125000 dbitrate 250000 fd on
+ *
+ * # CAN_1 link
+ * $ ip link set can1 up type can bitrate 125000 dbitrate 250000 fd on
+ * $ ip link set can2 up type can bitrate 125000 dbitrate 250000 fd on
+ *
+ * - Perform CAN test, run each of the pair commands in separate terminals:
+ * # CAN_0 link
+ * $ canfdtest -v can0
+ * $ canfdtest -g -v can3
+ *
+ * # CAN_1 link
+ * $ canfdtest -v can1
+ * $ canfdtest -g -v can2
+ */
+
+/dts-v1/;
+/plugin/;
+
+#include <dt-bindings/gpio/gpio.h>
+#include <dt-bindings/interrupt-controller/irq.h>
+
+&{/} {
+ /* Fixed clock dedicated to SPI CAN on 2-CH CAN FD HAT */
+ clk_can0: clk-ws-2ch-canfd0 {
+ compatible = "fixed-clock";
+ #clock-cells = <0>;
+ clock-frequency = <40000000>;
+ };
+
+ clk_can1: clk-ws-2ch-canfd1 {
+ compatible = "fixed-clock";
+ #clock-cells = <0>;
+ clock-frequency = <40000000>;
+ };
+
+ /*
+ * SPI_1 is operated as GPIO SPI, because MSIOF5 can not be
+ * muxed on the pins allocated for SPI_1 on this CANFD HAT.
+ */
+ spi-ws-2ch-canfd { /* SPI_1 */
+ #address-cells = <1>;
+ #size-cells = <0>;
+ compatible = "spi-gpio";
+ sck-gpios = <&gpio0 10 0>; /* CN7 pin 40 */
+ miso-gpios = <&gpio0 9 0>; /* CN7 pin 35 */
+ mosi-gpios = <&gpio0 12 0>; /* CN7 pin 38 */
+ cs-gpios = <&gpio2 13 GPIO_ACTIVE_LOW>; /* CN7 pin 12 */
+ num-chipselects = <1>;
+
+ can at 0 {
+ compatible = "microchip,mcp2518fd";
+ clocks = <&clk_can1>;
+ /* CN7 pin 18 */
+ interrupts-extended = <&gpio1 25 IRQ_TYPE_EDGE_FALLING>;
+ reg = <0>;
+ spi-max-frequency = <20000000>;
+ };
+ };
+};
+
+&msiof0 { /* SPI_0 */
+ #address-cells = <1>;
+ #size-cells = <0>;
+ pinctrl-0 = <&msiof0_pins>;
+ pinctrl-names = "default";
+ status = "okay";
+
+ /*
+ * Native MSIOF chipselect does not work with MCP2518FD
+ * because MCP251xFD driver needs to keep the chipselect
+ * line asserted between transfers. This requirement is
+ * fulfilled only by using GPIO chipselect.
+ */
+ cs-gpios = <&gpio1 8 GPIO_ACTIVE_LOW>;
+
+ can at 0 {
+ compatible = "microchip,mcp2518fd";
+ clocks = <&clk_can0>;
+ interrupts-extended = <&gpio1 26 IRQ_TYPE_EDGE_FALLING>;
+ reg = <0>;
+ spi-max-frequency = <20000000>;
+ };
+};
+
+&pfc {
+ msiof0_pins: spi-ws-2ch-canfd0 { /* SPI_0 */
+ groups = "msiof0_clk", "msiof0_txd", "msiof0_rxd";
+ function = "msiof0";
+ };
+};
+
+/*
+ * PWM1 uses PWM1_B pin configuration for pin GP2_13. This conflicts
+ * with SPI_1 CE_1 signal which is also on pin GP2_13. Disable PWM1
+ * in case this hat is in use.
+ */
+&pwm1 {
+ status = "disabled";
+};
--
2.53.0
More information about the linux-arm-kernel
mailing list