#include <i2c/smbus.h> file not found

Question

In my qt program I include the headers for i2c/smbus (as I did for other projects, also with yocto but different SoC vendor).

Kernel 4.14.24

extern "C"
{
#include <linux/i2c.h>
#include <linux/i2c-dev.h>
#include <i2c/smbus.h>       << FAIL: i2c/smbus.h: No such file or directory
#include <fcntl.h>
#include <sys/ioctl.h>
}

In the conf/local.conf file I added the i2c-tools

IMAGE_INSTALL_append = " i2c-tools "

Built the toolchain and checked the rootfs for i2c/smbus.h. No luck.
i2cdetect/get/set works (did before adding the i2c-tools too).

Functionalities implemented by /dev/i2c-0:
I2C                              yes
SMBus Quick Command              yes
SMBus Send Byte                  yes
SMBus Receive Byte               yes
SMBus Write Byte                 yes
SMBus Read Byte                  yes
SMBus Write Word                 yes
SMBus Read Word                  yes
SMBus Process Call               yes
SMBus Block Write                yes
SMBus Block Read                 yes
SMBus Block Process Call         no
SMBus PEC                        yes
I2C Block Write                  yes
I2C Block Read                   yes

I don't see the smbus.h in the rootfs: /usr/include/i2c/ There is a i2c-core-smbus.c where the functions i2c_smbus_......() are located but no h-file.

edit: added Kernel version.

Answer 1

The comment from @0andriy is correct, you need the libi2c-dev package.