change spidev master to slave

I see 3 devices in spidev, they are;

/dev/spidev1.0 /dev/spidev2.0 /dev/spidev2.1 /dev/spidev3.0 /dev/spidev3.1

and I have folder which is /sys/class/spi_master and there are 3 file spi1, spi2 and spi3. There is no spi_slave file in /sys/class folder. And also when I was trying spidev module, all of them(spi1,2 and 3) were master. So, how can I change property of spi’s to slave?

Have a check below document

Thank you @ShaneCCC