not able to read spi value, getting 0xff each time using nrf9160dk board

[sanjay kumar]

Followed the example https://github.com/Rallare/fw-nrfconnect-nrf/tree/nrf9160_samples/samples/nrf9160/spi

but getting spi received value 0xff each time

my conf file:

CONFIG_STDOUT_CONSOLE=y
CONFIG_PRINTK=y

CONFIG_I2C=y

CONFIG_SPI=y
CONFIG_SPI_3=y
CONFIG_SPI_NRFX=y

&spi3 {
status = "okay";
sck-pin = <30>;
mosi-pin = <27>;
miso-pin = <28>;
cs-gpios = <&gpio0 31 GPIO_ACTIVE_LOW>;
};

rest of the main code is same as I provided the github link

and my overlay file:

[Kenneth]

Do you have a logic analyzer trace of the SPI lines (csn, sck, miso and mosi)?