1 files changed, 43 insertions, 0 deletions
diff --git a/arch/arm/boot/dts/overlays/midi-uart1-overlay.dts b/arch/arm/boot/dts/overlays/midi-uart1-overlay.dts
new file mode 100644
index 000000000000..e0bc410acbff
--- /dev/null
+++ b/arch/arm/boot/dts/overlays/midi-uart1-overlay.dts
@@ -0,0 +1,43 @@
+/dts-v1/;
+/plugin/;
+
+#include <dt-bindings/clock/bcm2835-aux.h>
+
+/*
+ * Fake a higher clock rate to get a larger divisor, and thereby a lower
+ * baudrate. The real clock is 48MHz, which we scale so that requesting
+ * 38.4kHz results in an actual 31.25kHz.
+ *
+ *   48000000*38400/31250 = 58982400
+ */
+
+/{
+	compatible = "brcm,bcm2835";
+
+	fragment@0 {
+		target-path = "/clocks";
+		__overlay__ {
+			midi_clk: clock@5 {
+				compatible = "fixed-factor-clock";
+				#clock-cells = <0>;
+				clocks = <&aux BCM2835_AUX_CLOCK_UART>;
+				clock-mult = <38400>;
+				clock-div  = <31250>;
+			};
+		};
+	};
+
+	fragment@1 {
+		target = <&uart1>;
+		__overlay__ {
+			clocks = <&midi_clk>;
+		};
+	};
+
+	fragment@2 {
+		target = <&aux>;
+		__overlay__ {
+			clock-output-names = "aux_uart", "aux_spi1", "aux_spi2";
+		};
+	};
+};