diff --git a/drivers/spi/spi-cadence.c b/drivers/spi/spi-cadence.c index a23d4f6329f5..00f0d1b3a722 100644 --- a/drivers/spi/spi-cadence.c +++ b/drivers/spi/spi-cadence.c @@ -69,6 +69,7 @@ #define CDNS_SPI_BAUD_DIV_SHIFT 3 /* Baud rate divisor shift in CR */ #define CDNS_SPI_SS_SHIFT 10 /* Slave Select field shift in CR */ #define CDNS_SPI_SS0 0x1 /* Slave Select zero */ +#define CDNS_SPI_NOSS 0x3C /* No Slave select */ /* * SPI Interrupt Registers bit Masks @@ -450,15 +451,20 @@ static int cdns_prepare_transfer_hardware(struct spi_master *master) * @master: Pointer to the spi_master structure which provides * information about the controller. * - * This function disables the SPI master controller. + * This function disables the SPI master controller when no slave selected. * * Return: 0 always */ static int cdns_unprepare_transfer_hardware(struct spi_master *master) { struct cdns_spi *xspi = spi_master_get_devdata(master); + u32 ctrl_reg; - cdns_spi_write(xspi, CDNS_SPI_ER, CDNS_SPI_ER_DISABLE); + /* Disable the SPI if slave is deselected */ + ctrl_reg = cdns_spi_read(xspi, CDNS_SPI_CR); + ctrl_reg = (ctrl_reg & CDNS_SPI_CR_SSCTRL) >> CDNS_SPI_SS_SHIFT; + if (ctrl_reg == CDNS_SPI_NOSS) + cdns_spi_write(xspi, CDNS_SPI_ER, CDNS_SPI_ER_DISABLE); return 0; }