drivers: display: st: allow-ltdc-callback-override

Allow overriding the LTDC callback for manual handling or extension
In some cases, the default handling may not be desired, for example
triggering handling of the next frame/block once the transfer has passed
a certain line.

Signed-off-by: Mathias Markussen <mathias.markussen@st.com>

Author: markussmST

drivers/display/display_stm32_ltdc.c

@@ -1,7 +1,7 @@
 /*
  * Copyright (c) 2022 Byte-Lab d.o.o. <dev@byte-lab.com>
  * Copyright 2023 NXP
- * Copyright (c) 2024 STMicroelectronics
+ * Copyright (c) 2025 STMicroelectronics
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -21,6 +21,7 @@
 #include <zephyr/pm/device.h>
 #include <zephyr/sys/barrier.h>
 #include <zephyr/cache.h>
+#include <zephyr/drivers/display/display_stm32_ltdc.h>
 #if defined(CONFIG_STM32_LTDC_FB_USE_SHARED_MULTI_HEAP)
 #include <zephyr/multi_heap/shared_multi_heap.h>
 #endif
@@ -84,7 +85,7 @@ struct display_stm32_ltdc_config {
 	const struct device *display_controller;
 };
 
-static void stm32_ltdc_global_isr(const struct device *dev)
+void __weak stm32_ltdc_global_isr(const struct device *dev)
 {
 	struct display_stm32_ltdc_data *data = dev->data;
 

drivers/display/display_stm32_ltdc.h

@@ -0,0 +1,12 @@
+/*
+ * Copyright 2025, STMicroelectronics
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef _ZEPHYR_DRIVERS_DISPLAY_STM32_LTDC_H_
+#define _ZEPHYR_DRIVERS_DISPLAY_STM32_LTDC_H_
+
+void stm32_ltdc_global_isr(const struct device *dev);
+
+#endif /* _ZEPHYR_DRIVERS_DISPLAY_STM32_LTDC_H_ */