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 --- drivers/spi/mxs_spi.c | 12 +++--------- 1 file changed, 3 insertions(+), 9 deletions(-)
V2: Clean up a warning that "ssp_regs" are not used
diff --git a/drivers/spi/mxs_spi.c b/drivers/spi/mxs_spi.c index 3cf7142..2b9f395 100644 --- a/drivers/spi/mxs_spi.c +++ b/drivers/spi/mxs_spi.c @@ -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;