spi: spi-imx: add support for SPI_MOSI_IDLE_LOW mode bit

By default, the spi-imx controller pulls the mosi line high, whenever it
is idle. This behaviour can be inverted per CS by setting the
corresponding DATA_CTL bit in the config register of the controller.

Also, since the controller mode-bits have to be touched anyways, the
SPI_CPOL and SPI_CPHA are replaced by the combined SPI_MODE_X_MASK flag.

Signed-off-by: Boerge Struempfel <boerge.struempfel@gmail.com>
Link: https://lore.kernel.org/r/20230530141641.1155691-3-boerge.struempfel@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c
index bd6ddb142b133bfa73a457050b5126f12004be17..6f4d3cb81fdf5b74f2a95bc71f32822c29821cd8 100644 (file)
--- a/drivers/spi/spi-imx.c
+++ b/drivers/spi/spi-imx.c
@@ -281,6 +281,7 @@ static bool spi_imx_can_dma(struct spi_controller *controller, struct spi_device
 #define MX51_ECSPI_CONFIG_SCLKPOL(cs)  (1 << ((cs & 3) +  4))
 #define MX51_ECSPI_CONFIG_SBBCTRL(cs)  (1 << ((cs & 3) +  8))
 #define MX51_ECSPI_CONFIG_SSBPOL(cs)   (1 << ((cs & 3) + 12))
+#define MX51_ECSPI_CONFIG_DATACTL(cs)  (1 << ((cs & 3) + 16))
 #define MX51_ECSPI_CONFIG_SCLKCTL(cs)  (1 << ((cs & 3) + 20))
 
 #define MX51_ECSPI_INT         0x10
@@ -573,6 +574,11 @@ static int mx51_ecspi_prepare_message(struct spi_imx_data *spi_imx,
                cfg &= ~MX51_ECSPI_CONFIG_SCLKCTL(spi_get_chipselect(spi, 0));
        }
 
+       if (spi->mode & SPI_MOSI_IDLE_LOW)
+               cfg |= MX51_ECSPI_CONFIG_DATACTL(spi_get_chipselect(spi, 0));
+       else
+               cfg &= ~MX51_ECSPI_CONFIG_DATACTL(spi_get_chipselect(spi, 0));
+
        if (spi->mode & SPI_CS_HIGH)
                cfg |= MX51_ECSPI_CONFIG_SSBPOL(spi_get_chipselect(spi, 0));
        else
@@ -1743,7 +1749,8 @@ static int spi_imx_probe(struct platform_device *pdev)
        controller->prepare_message = spi_imx_prepare_message;
        controller->unprepare_message = spi_imx_unprepare_message;
        controller->slave_abort = spi_imx_slave_abort;
-       controller->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_NO_CS;
+       controller->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_NO_CS |
+                               SPI_MOSI_IDLE_LOW;
 
        if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx) ||
            is_imx53_ecspi(spi_imx))