nvs: allow to specify custom partition

Closes https://github.com/espressif/esp-idf/pull/5172

components/nvs_flash/include/nvs_flash.h

@@ -61,6 +61,20 @@ esp_err_t nvs_flash_init(void);
  */
 esp_err_t nvs_flash_init_partition(const char *partition_label);
 
+/**
+ * @brief Initialize NVS flash storage for the partition specified by partition pointer.
+ *
+ * @param[in] partition pointer to a partition obtained by the ESP partition API.
+ *
+ * @return
+ *      - ESP_OK if storage was successfully initialized
+ *      - ESP_ERR_NVS_NO_FREE_PAGES if the NVS storage contains no empty pages
+ *        (which may happen if NVS partition was truncated)
+ *      - ESP_ERR_INVALID_ARG in case partition is NULL
+ *      - one of the error codes from the underlying flash storage driver
+ */
+esp_err_t nvs_flash_init_partition_ptr(const esp_partition_t *partition);
+
 /**
  * @brief Deinitialize NVS storage for the default NVS partition
  *
@@ -118,6 +132,26 @@ esp_err_t nvs_flash_erase(void);
  */
 esp_err_t nvs_flash_erase_partition(const char *part_name);
 
+/**
+ * @brief Erase custom partition.
+ *
+ * Erase all content of specified custom partition.
+ *
+ * @note
+ *  If the partition is initialized, this function first de-initializes it.
+ *  Afterwards, the partition has to be initialized again to be used.
+ *
+ * @param[in] partition pointer to a partition obtained by the ESP partition API.
+ *
+ * @return
+ *      - ESP_OK on success
+ *      - ESP_ERR_NOT_FOUND if there is no partition with the specified
+ *        parameters in the partition table
+ *      - ESP_ERR_INVALID_ARG in case partition is NULL
+ *      - one of the error codes from the underlying flash storage driver
+ */
+esp_err_t nvs_flash_erase_partition_ptr(const esp_partition_t *partition);
+
 /**
  * @brief Initialize the default NVS partition.
  *

components/nvs_flash/src/nvs_api.cpp

@@ -127,6 +127,20 @@ static esp_err_t close_handles_and_deinit(const char* part_name)
     return NVSPartitionManager::get_instance()->deinit_partition(part_name);
 }
 
+extern "C" esp_err_t nvs_flash_init_partition_ptr(const esp_partition_t *partition)
+{
+    Lock::init();
+    Lock lock;
+
+    if (!partition) {
+        return ESP_ERR_INVALID_ARG;
+    }
+
+    return nvs_flash_init_custom(partition->label,
+                                 partition->address / SPI_FLASH_SEC_SIZE,
+                                 partition->size / SPI_FLASH_SEC_SIZE);
+}
+
 #ifdef ESP_PLATFORM
 extern "C" esp_err_t nvs_flash_init_partition(const char *part_name)
 {
@@ -193,6 +207,28 @@ extern "C" esp_err_t nvs_flash_erase_partition(const char *part_name)
     return esp_partition_erase_range(partition, 0, partition->size);
 }
 
+extern "C" esp_err_t nvs_flash_erase_partition_ptr(const esp_partition_t *partition)
+{
+    Lock::init();
+    Lock lock;
+
+    if (!partition) {
+        return ESP_ERR_INVALID_ARG;
+    }
+
+    // if the partition is initialized, uninitialize it first
+    if (NVSPartitionManager::get_instance()->lookup_storage_from_name(partition->label)) {
+        const esp_err_t err = close_handles_and_deinit(partition->label);
+
+        // only hypothetical/future case, deinit_partition() only fails if partition is uninitialized
+        if (err != ESP_OK) {
+            return err;
+        }
+    }
+
+    return esp_partition_erase_range(partition, 0, partition->size);
+}
+
 extern "C" esp_err_t nvs_flash_erase(void)
 {
     return nvs_flash_erase_partition(NVS_DEFAULT_PART_NAME);