[PATCH v3 2/6] spi: sun6i: handle chip select polarity flag

Sergey Suloev ssuloev at orpaltech.com
Tue Apr 3 08:44:45 PDT 2018


The chip select polarity flag is declared as supported
but is not handled in the code.

Signed-off-by: Sergey Suloev <ssuloev at orpaltech.com>
---
 drivers/spi/spi-sun6i.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/spi/spi-sun6i.c b/drivers/spi/spi-sun6i.c
index 88ad45e..78acc1f 100644
--- a/drivers/spi/spi-sun6i.c
+++ b/drivers/spi/spi-sun6i.c
@@ -193,6 +193,12 @@ static void sun6i_spi_set_cs(struct spi_device *spi, bool enable)
 	else
 		reg &= ~SUN6I_TFR_CTL_CS_LEVEL;
 
+	/* Handle chip select "reverse" polarity */
+	if (spi->mode & SPI_CS_HIGH)
+		reg &= ~SUN6I_TFR_CTL_SPOL;
+	else
+		reg |= SUN6I_TFR_CTL_SPOL;
+
 	/* We want to control the chip select manually */
 	reg |= SUN6I_TFR_CTL_CS_MANUAL;
 
-- 
2.16.2




More information about the linux-arm-kernel mailing list