[PATCH v2] spi: Ensure that CS line is in non-active state after spi_setup()

From: Ivan T. Ivanov
Date: Fri Mar 13 2015 - 12:44:12 EST


Some devices samples state of the chip select signal during power up
and act differently based on this state, so SPI core should ensure
that CS line is driven in non-active state after spi_setup().

Signed-off-by: Ivan T. Ivanov <iivanov@xxxxxxxxxx>
---
drivers/spi/spi.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index c64a3e5..4023cc9 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -1893,6 +1893,8 @@ int spi_setup(struct spi_device *spi)
if (!spi->max_speed_hz)
spi->max_speed_hz = spi->master->max_speed_hz;

+ spi_set_cs(spi, false);
+
if (spi->master->setup)
status = spi->master->setup(spi);

--
1.9.1

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