Unified codebase for TX28, TX48, TX51, TX53

[karo-tx-uboot.git] / drivers / spi / mxs_spi.c

diff --git a/drivers/spi/mxs_spi.c b/drivers/spi/mxs_spi.c
index 4e6f14ee0722d102b2db33cdcb67ff1c02a1c272..7859536a6725569da9ad439b8f4d49e3a5672194 100644 (file)
--- a/drivers/spi/mxs_spi.c
+++ b/drivers/spi/mxs_spi.c
@@ -34,6 +34,8 @@
 
 #define        MXS_SPI_MAX_TIMEOUT     1000000
 #define        MXS_SPI_PORT_OFFSET     0x2000
+#define MXS_SSP_CHIPSELECT_MASK                0x00300000
+#define MXS_SSP_CHIPSELECT_SHIFT       20
 
 struct mxs_spi_slave {
        struct spi_slave        slave;
@@ -51,14 +53,25 @@ void spi_init(void)
 {
 }
 
+int spi_cs_is_valid(unsigned int bus, unsigned int cs)
+{
+       /* MXS SPI: 4 ports and 3 chip selects maximum */
+       if (bus > 3 || cs > 2)
+               return 0;
+       else
+               return 1;
+}
+
 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
                                  unsigned int max_hz, unsigned int mode)
 {
        struct mxs_spi_slave *mxs_slave;
        uint32_t addr;
+       struct mx28_ssp_regs *ssp_regs;
+       int reg;
 
-       if (bus > 3) {
-               printf("MXS SPI: Max bus number is 3\n");
+       if (!spi_cs_is_valid(bus, cs)) {
+               printf("mxs_spi: invalid bus %d / chip select %d\n", bus, cs);
                return NULL;
        }
 
@@ -73,7 +86,13 @@ struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
        mxs_slave->max_khz = max_hz / 1000;
        mxs_slave->mode = mode;
        mxs_slave->regs = (struct mx28_ssp_regs *)addr;
+       ssp_regs = mxs_slave->regs;
+
+       reg = readl(&ssp_regs->hw_ssp_ctrl0);
+       reg &= ~(MXS_SSP_CHIPSELECT_MASK);
+       reg |= cs << MXS_SSP_CHIPSELECT_SHIFT;
 
+       writel(reg, &ssp_regs->hw_ssp_ctrl0);
        return &mxs_slave->slave;
 }