flash: implement flash driver model

Makefile

@@ -22,6 +22,8 @@ obj-y += source/shell.o
 obj-y += source/spi_flash.o
 obj-y += source/usart.o
 
+obj-y += source/core/flash.o
+
 obj = $(addprefix $(BUILD)/, $(obj-y))
 
 # Include the dependencies.

include/flash.h

@@ -0,0 +1,20 @@
+#pragma once
+
+struct flash_dev;
+
+struct flash_ops {
+	int (* read)(struct flash_dev *dev, uint32_t addr, void *data, size_t len);
+	int (* write)(struct flash_dev *dev, uint32_t addr, const void *data,
+		size_t len);
+	int (* erase)(struct flash_dev *dev, uint32_t addr, size_t len);
+};
+
+struct flash_dev {
+	struct flash_ops *ops;
+	void *priv;
+};
+
+int flash_read(struct flash_dev *dev, uint32_t addr, void *data, size_t len);
+int flash_write(struct flash_dev *dev, uint32_t addr, const void *data,
+	size_t len);
+int flash_erase(struct flash_dev *dev, uint32_t addr, size_t len);

source/core/flash.c

@@ -0,0 +1,29 @@
+#include <stdint.h>
+#include <stdlib.h>
+
+#include <flash.h>
+
+int flash_read(struct flash_dev *dev, uint32_t addr, void *data, size_t len)
+{
+	if (!dev)
+		return -1;
+
+	return dev->ops->read(dev, addr, data, len);
+}
+
+int flash_write(struct flash_dev *dev, uint32_t addr, const void *data,
+	size_t len)
+{
+	if (!dev)
+		return -1;
+
+	return dev->ops->write(dev, addr, data, len);
+}
+
+int flash_erase(struct flash_dev *dev, uint32_t addr, size_t len)
+{
+	if (!dev)
+		return -1;
+
+	return dev->ops->erase(dev, addr, len);
+}