spi: mxs_spi: Configure chipselect after block reset
authorMarek Vasut <marex@denx.de>
Mon, 26 Aug 2013 15:45:23 +0000 (17:45 +0200)
committerJagannadha Sutradharudu Teki <jaganna@xilinx.com>
Tue, 27 Aug 2013 14:09:39 +0000 (19:39 +0530)
The chipselect must be written into the CTRL0 register after the SSP
block is reset, otherwise the block will always use ChipSelect #0.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>
Cc: Otavio Salvador <otavio@ossystems.com.br>
Cc: Stefano Babic <sbabic@denx.de>
Acked-by: Stefano Babic <sbabic@denx.de>
drivers/spi/mxs_spi.c

index 3cf7142f5a62d0610fbf938fe74df672d5a5f99b..2b9f395a97821568dc12c5e28feaaf42b42ffd50 100644 (file)
@@ -56,8 +56,6 @@ 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;
-       struct mxs_ssp_regs *ssp_regs;
-       int reg;
 
        if (!spi_cs_is_valid(bus, cs)) {
                printf("mxs_spi: invalid bus %d / chip select %d\n", bus, cs);
@@ -74,13 +72,7 @@ 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 = mxs_ssp_regs_by_bus(bus);
-       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;
 
 err_init:
@@ -102,7 +94,9 @@ int spi_claim_bus(struct spi_slave *slave)
 
        mxs_reset_block(&ssp_regs->hw_ssp_ctrl0_reg);
 
-       writel(SSP_CTRL0_BUS_WIDTH_ONE_BIT, &ssp_regs->hw_ssp_ctrl0);
+       writel((slave->cs << MXS_SSP_CHIPSELECT_SHIFT) |
+              SSP_CTRL0_BUS_WIDTH_ONE_BIT,
+              &ssp_regs->hw_ssp_ctrl0);
 
        reg = SSP_CTRL1_SSP_MODE_SPI | SSP_CTRL1_WORD_LENGTH_EIGHT_BITS;
        reg |= (mxs_slave->mode & SPI_CPOL) ? SSP_CTRL1_POLARITY : 0;