Non-volatile Storage APIs

Non-volatile Storage APIs. More...

Functions
int	nvs_mount (struct nvs_fs *fs)
	nvs_mount More...
int	nvs_clear (struct nvs_fs *fs)
	nvs_clear More...
ssize_t	nvs_write (struct nvs_fs *fs, uint16_t id, const void *data, size_t len)
	nvs_write More...
int	nvs_delete (struct nvs_fs *fs, uint16_t id)
	nvs_delete More...
ssize_t	nvs_read (struct nvs_fs *fs, uint16_t id, void *data, size_t len)
	nvs_read More...
ssize_t	nvs_read_hist (struct nvs_fs *fs, uint16_t id, void *data, size_t len, uint16_t cnt)
	nvs_read_hist More...
ssize_t	nvs_calc_free_space (struct nvs_fs *fs)
	nvs_calc_free_space More...

Detailed Description

Non-volatile Storage APIs.

Function Documentation

nvs_calc_free_space()

ssize_t nvs_calc_free_space

(

struct nvs_fs *

fs

)

#include <include/zephyr/fs/nvs.h>

nvs_calc_free_space

Calculate the available free space in the file system.

Parameters

fs	Pointer to file system

Returns

Number of bytes free. On success, it will be equal to the number of bytes that can still be written to the file system. Calculating the free space is a time consuming operation, especially on spi flash. On error, returns negative value of errno.h defined error codes.

nvs_clear()

int nvs_clear

(

struct nvs_fs *

fs

)

#include <include/zephyr/fs/nvs.h>

nvs_clear

Clears the NVS file system from flash.

Parameters

fs	Pointer to file system

Return values

0	Success
-ERRNO	errno code if error

nvs_delete()

int nvs_delete	(	struct nvs_fs *	fs,
		uint16_t	id
	)

#include <include/zephyr/fs/nvs.h>

nvs_delete

Delete an entry from the file system

Parameters

fs	Pointer to file system
id	Id of the entry to be deleted

Return values

0	Success
-ERRNO	errno code if error

nvs_mount()

int nvs_mount

(

struct nvs_fs *

fs

)

#include <include/zephyr/fs/nvs.h>

nvs_mount

Mount a NVS file system onto the flash device specified in fs.

Parameters

fs	Pointer to file system

Return values

0	Success
-ERRNO	errno code if error

nvs_read()

ssize_t nvs_read	(	struct nvs_fs *	fs,
		uint16_t	id,
		void *	data,
		size_t	len
	)

#include <include/zephyr/fs/nvs.h>

nvs_read

Read an entry from the file system.

Parameters

fs	Pointer to file system
id	Id of the entry to be read
data	Pointer to data buffer
len	Number of bytes to be read

Returns

Number of bytes read. On success, it will be equal to the number of bytes requested to be read. When the return value is larger than the number of bytes requested to read this indicates not all bytes were read, and more data is available. On error, returns negative value of errno.h defined error codes.

nvs_read_hist()

ssize_t nvs_read_hist	(	struct nvs_fs *	fs,
		uint16_t	id,
		void *	data,
		size_t	len,
		uint16_t	cnt
	)

#include <include/zephyr/fs/nvs.h>

nvs_read_hist

Read a history entry from the file system.

Parameters

fs	Pointer to file system
id	Id of the entry to be read
data	Pointer to data buffer
len	Number of bytes to be read
cnt	History counter: 0: latest entry, 1: one before latest ...

Returns

Number of bytes read. On success, it will be equal to the number of bytes requested to be read. When the return value is larger than the number of bytes requested to read this indicates not all bytes were read, and more data is available. On error, returns negative value of errno.h defined error codes.

nvs_write()

ssize_t nvs_write	(	struct nvs_fs *	fs,
		uint16_t	id,
		const void *	data,
		size_t	len
	)

#include <include/zephyr/fs/nvs.h>

nvs_write

Write an entry to the file system.

Parameters

fs	Pointer to file system
id	Id of the entry to be written
data	Pointer to the data to be written
len	Number of bytes to be written

Returns

Number of bytes written. On success, it will be equal to the number of bytes requested to be written. When a rewrite of the same data already stored is attempted, nothing is written to flash, thus 0 is returned. On error, returns negative value of errno.h defined error codes.