Using chips with different cpol, causes first communication to fail on cpol change. To avoid this issue write cr0 register before cs is set. Suggested-by: Lukasz Zemla <Lukasz.Zemla@xxxxxxxxxxxx> Signed-off-by: Edmund Berenson <edmund.berenson@xxxxxxxxx> --- drivers/spi/spi-dw-core.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/spi/spi-dw-core.c b/drivers/spi/spi-dw-core.c index 57c9e384d6d4..c3da4fe3e510 100644 --- a/drivers/spi/spi-dw-core.c +++ b/drivers/spi/spi-dw-core.c @@ -93,6 +93,7 @@ static inline void dw_spi_debugfs_remove(struct dw_spi *dws) void dw_spi_set_cs(struct spi_device *spi, bool enable) { struct dw_spi *dws = spi_controller_get_devdata(spi->controller); + struct dw_spi_chip_data *chip = spi_get_ctldata(spi); bool cs_high = !!(spi->mode & SPI_CS_HIGH); u8 enable_cs = 0; @@ -106,8 +107,13 @@ void dw_spi_set_cs(struct spi_device *spi, bool enable) * Enable register no matter whether the SPI core is configured to * support active-high or active-low CS level. */ - if (cs_high == enable) + if (cs_high == enable) { + dw_spi_enable_chip(dws, 0); + dw_writel(dws, DW_SPI_CTRLR0, chip->cr0); + dw_spi_enable_chip(dws, 1); + dw_writel(dws, DW_SPI_SER, BIT(enable_cs)); + } else dw_writel(dws, DW_SPI_SER, 0); } -- 2.37.4