spi: spi-synquacer: fix set_cs handling

commit 1c9f1750f0305bf605ff22686fc0ac89c06deb28 upstream.

When the slave chip select is deasserted, DMSTOP bit
must be set.

Fixes: b0823ee35cf9 ("spi: Add spi driver for Socionext SynQuacer platform")
Signed-off-by: Masahisa Kojima <masahisa.kojima@linaro.org>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210201073109.9036-1-jassisinghbrar@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/spi/spi-synquacer.c b/drivers/spi/spi-synquacer.c
index 8cdca6a..ea706d9 100644 (file)
--- a/drivers/spi/spi-synquacer.c
+++ b/drivers/spi/spi-synquacer.c
@@ -490,6 +490,10 @@ static void synquacer_spi_set_cs(struct spi_device *spi, bool enable)
        val &= ~(SYNQUACER_HSSPI_DMPSEL_CS_MASK <<
                 SYNQUACER_HSSPI_DMPSEL_CS_SHIFT);
        val |= spi->chip_select << SYNQUACER_HSSPI_DMPSEL_CS_SHIFT;
+
+       if (!enable)
+               val |= SYNQUACER_HSSPI_DMSTOP_STOP;
+
        writel(val, sspi->regs + SYNQUACER_HSSPI_REG_DMSTART);
 }