drivers/flash: Flash API: device size getter

The commit adds flash_get_size  API functions.

Signed-off-by: Dominik Ermel <[email protected]>

Author: de-nordic

drivers/flash/flash_handlers.c

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2017 Intel Corporation
+ * Copyright (c) 2024 Nordic Semiconductor ASA
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -36,6 +37,14 @@ static inline int z_vrfy_flash_erase(const struct device *dev, off_t offset,
 }
 #include <zephyr/syscalls/flash_erase_mrsh.c>
 
+static inline int z_vrfy_flash_get_size(const struct device *dev, uint64_t *size)
+{
+	K_OOPS(K_SYSCALL_OBJ(dev, K_OBJ_DRIVER_FLASH));
+	K_OOPS(K_SYSCALL_MEMORY_WRITE(size, sizeof(size)));
+	return z_impl_flash_get_size((const struct device *)dev, size);
+}
+#include <zephyr/syscalls/flash_get_size_mrsh.c>
+
 static inline size_t z_vrfy_flash_get_write_block_size(const struct device *dev)
 {
 	K_OOPS(K_SYSCALL_OBJ(dev, K_OBJ_DRIVER_FLASH));

include/zephyr/drivers/flash.h

@@ -155,6 +155,18 @@ typedef int (*flash_api_write)(const struct device *dev, off_t offset,
 typedef int (*flash_api_erase)(const struct device *dev, off_t offset,
 			       size_t size);
 
+/**
+ * @brief Get device size in bytes.
+ *
+ * Returns total logical device size in bytes.
+ *
+ * @param[in] dev	flash device.
+ * @param[out] size	device size in bytes.
+ *
+ * @return 0 on success, negative errno code on error.
+ */
+typedef int (*flash_api_get_size)(const struct device *dev, uint64_t *size);
+
 typedef const struct flash_parameters* (*flash_api_get_parameters)(const struct device *dev);
 
 #if defined(CONFIG_FLASH_PAGE_LAYOUT)
@@ -195,6 +207,7 @@ __subsystem struct flash_driver_api {
 	flash_api_write write;
 	flash_api_erase erase;
 	flash_api_get_parameters get_parameters;
+	flash_api_get_size get_size;
 #if defined(CONFIG_FLASH_PAGE_LAYOUT)
 	flash_api_pages_layout page_layout;
 #endif /* CONFIG_FLASH_PAGE_LAYOUT */
@@ -321,6 +334,33 @@ static inline int z_impl_flash_erase(const struct device *dev, off_t offset,
 	return rc;
 }
 
+/**
+ * @brief Get device size in bytes.
+ *
+ * Returns total logical device size in bytes. Not all devices may support
+ * returning size, specifically those with non uniform page layouts or banked,
+ * in which case the function will return -ENOTSUP, and user has to rely
+ * on Flash page layout functions enabled by CONFIG_FLASH_PAGE_LAYOUT.
+ *
+ * @param[in] dev	flash device.
+ * @param[out] size	device size in bytes.
+ *
+ * @return 0 on success, negative errno code on error.
+ */
+__syscall int flash_get_size(const struct device *dev, uint64_t *size);
+
+static inline int z_impl_flash_get_size(const struct device *dev, uint64_t *size)
+{
+	int rc = -ENOSYS;
+	const struct flash_driver_api *api = (const struct flash_driver_api *)dev->api;
+
+	if (api->get_size != NULL) {
+		rc = api->get_size(dev, size);
+	}
+
+	return rc;
+}
+
 /**
  * @brief Fill selected range of device with specified value
  *