"IGNORE_CRC bit: In SPI/SSI modes: When set to 1, deassert the chip select (SSn) pin after the command is executed." Then I tought that mxs_spi_end_xfer should be also called in the case where bitlen==0. In current code this does not happen. > It seems that the mainline linux only implements a GPIO based SPI driver. > So we cannot take it for reference. There is no mxs spi driver in the mainline kernel yet.