SPI_SH_RBF
ss->cr1 &= ~SPI_SH_RBF;
spi_sh_set_bit(ss, SPI_SH_RBF, SPI_SH_CR4);
ss->cr1 & SPI_SH_RBF,
if (cr1 & SPI_SH_RBF)
ss->cr1 |= SPI_SH_RBF;