soc: st: add stm32u535 support

Adds the u535 soc, similar to the u545 except without the AES HW
accelerator

signed-off-by: Harris Tomy <harristomy@gmail.com>

dts/arm/st/u5/stm32u535.dtsi

@@ -0,0 +1,38 @@
+/*
+ * Copyright (c) 2025 Harris Tomy
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <st/u5/stm32u5.dtsi>
+
+/ {
+	soc {
+		/* USB-C PD is not available on this part. */
+		/delete-node/ ucpd@4000dc00;
+
+		/* Advanced Encryption Standard HW accelerator is not available on this part. */
+		/delete-node/ aes@420c0000;
+
+		compatible = "st,stm32u535", "st,stm32u5", "simple-bus";
+
+		usb: usb@40016000 {
+			compatible = "st,stm32-usb";
+			reg = <0x40016000 0x400>;
+			interrupts = <73 0>;
+			interrupt-names = "usb";
+			num-bidir-endpoints = <8>;
+			ram-size = <2048>;
+			maximum-speed = "full-speed";
+			clocks = <&rcc STM32_CLOCK(APB2, 24)>,
+				<&rcc STM32_SRC_HSI48 ICKLK_SEL(0)>;
+			phys = <&usb_fs_phy>;
+			status = "disabled";
+		};
+	};
+
+	usb_fs_phy: usb_fs_phy {
+		compatible = "usb-nop-xceiv";
+		#phy-cells = <0>;
+	};
+};

dts/arm/st/u5/stm32u535Xi.dtsi

@@ -0,0 +1,28 @@
+/*
+ * Copyright (c) 2025 Harris Tomy
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <mem.h>
+#include <st/u5/stm32u535.dtsi>
+
+/ {
+	sram0: memory@20000000 {
+		/* SRAM1 + SRAM2 */
+		reg = <0x20000000 DT_SIZE_K(256)>;
+	};
+
+	sram1: memory@28000000 {
+		/* SRAM4, low-power background autonomous mode */
+		reg = <0x28000000 DT_SIZE_K(16)>;
+	};
+
+	soc {
+		flash-controller@40022000 {
+			flash0: flash@8000000 {
+				reg = <0x08000000 DT_SIZE_K(512)>;
+			};
+		};
+	};
+};

soc/st/stm32/soc.yml

@@ -206,6 +206,7 @@ family:
     - name: stm32u5a5xx
     - name: stm32u5a9xx
     - name: stm32u5g9xx
+    - name: stm32u535xx
     - name: stm32u545xx
     - name: stm32u575xx
     - name: stm32u585xx

soc/st/stm32/stm32u5x/Kconfig.defconfig.stm32u535xx

@@ -0,0 +1,11 @@
+# ST Microelectronics STM32U535XX MCU
+
+# Copyright (c) 2025 Harris Tomy
+# SPDX-License-Identifier: Apache-2.0
+
+if SOC_STM32U535XX
+
+config NUM_IRQS
+	default 126
+
+endif # SOC_STM32U535XX

soc/st/stm32/stm32u5x/Kconfig.soc

@@ -4,6 +4,7 @@
 # Copyright (c) 2023 PSICONTROL nv
 # Copyright (c) 2023 STMicroelectronics
 # Copyright (c) 2025 Charles Dias
+# Copyright (c) 2025 Harris Tomy
 # SPDX-License-Identifier: Apache-2.0
 
 config SOC_SERIES_STM32U5X
@@ -13,6 +14,10 @@ config SOC_SERIES_STM32U5X
 config SOC_SERIES
 	default "stm32u5x" if SOC_SERIES_STM32U5X
 
+config SOC_STM32U535XX
+	bool
+	select SOC_SERIES_STM32U5X
+
 config SOC_STM32U545XX
 	bool
 	select SOC_SERIES_STM32U5X
@@ -49,6 +54,7 @@ config SOC
 	default "stm32u5a5xx" if SOC_STM32U5A5XX
 	default "stm32u5a9xx" if SOC_STM32U5A9XX
 	default "stm32u5g9xx" if SOC_STM32U5G9XX
+	default "stm32u535xx" if SOC_STM32U535XX
 	default "stm32u545xx" if SOC_STM32U545XX
 	default "stm32u575xx" if SOC_STM32U575XX
 	default "stm32u585xx" if SOC_STM32U585XX