We have got a Freescale's IMX6DL reference board (Wandboard Dual). We have ported Ubuntu to this and able to boot successfully. Now we would like interface some other modules to this board externally through SPI. We have made entry for spi module in device tree and when we are booting we could able to see /dev/spidev0.0. And also we checked with spi_test.c program which is confirming that the board is working as spi master (spi is working correctly) by shorting MOSI and MISO pins in JP4. But how we can check the correctness of SPI slave devices correctly. Whether that hardware working or not, connections are correct etc. how we will come to know about spi slave devices connected.. in the linux user space.