----------------------------------------------------------------------------------------------

keep unused burst */

disbale spi bus */

enable spi bus */

enable irq type */

query irq pending */

reset fifo */

restore reg data after transfer complete */

select dma type */

set ss control */

set ss level */

flush d-cache */

* <= 64 : cpu ; > 64 : dma * wait for done completion in this function, wakup in the irq hanlder */

* change the properties of spi device with spi transfer. * every spi transfer must call this interface to update the master to the excute transfer *