[U-Boot] [PATCH V2] spi: mxs: Configure chipselect after block reset
Marek Vasut
marex at denx.de
Mon Aug 26 17:45:23 CEST 2013
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 at denx.de>
Cc: Fabio Estevam <fabio.estevam at freescale.com>
Cc: Jagannadha Sutradharudu Teki <jagannadh.teki at gmail.com>
Cc: Otavio Salvador <otavio at ossystems.com.br>
Cc: Stefano Babic <sbabic at 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;
--
1.7.10.4
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