dts: arm: st: c0: Add clk-hsi48 for stm32c071 SOC

Allow to use internal HSI to clock the USB bus if HSE is not available.

Signed-off-by: Tomáš Juřena <jurenatomas@gmail.com>

Author: jurenat

boards/st/nucleo_c071rb/nucleo_c071rb.dts

@@ -78,6 +78,11 @@
 	status = "okay";
 };
 
+&clk_hsi48 {
+	status = "okay";
+	crs-usb-sof;
+};
+
 &rcc {
 	clocks = <&clk_hse>;
 	clock-frequency = <DT_FREQ_M(48)>;

dts/arm/st/c0/stm32c071.dtsi

@@ -7,6 +7,16 @@
 #include <st/c0/stm32c031.dtsi>
 
 / {
+
+	clocks {
+		clk_hsi48: clk-hsi48 {
+			#clock-cells = <0>;
+			compatible = "st,stm32-hsi48-clock";
+			clock-frequency = <DT_FREQ_M(48)>;
+			status = "disabled";
+		};
+	};
+
 	soc {
 		compatible = "st,stm32c071", "st,stm32c0", "simple-bus";
 
@@ -77,6 +87,7 @@
 		dmamux1: dmamux@40020800 {
 			dma-channels = <5>;
 		};
+
 	};
 
 	usb_fs_phy: usbphy {