[PATCH RFC] spi/gpio: start with CS non-active

["Uwe Kleine-König" <u.kleine-koenig-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org>]

The chip select line was configured as output with the initial value
being active explicitly. It was later deasserted during
spi_bitbang_setup() without any clock activity in between. So it makes
no sense to activate the device at all and the chip select line can
better start non-active.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
---
Hello,

I'm not sure if an active chip select line without any clock activity can
confuse a device. If so, this patch might qualify as fix. But with my
limited knowledge about spi it's also possible that I just miss why the
active chip select is important. For the devices I have it doesn't seem
to make a difference.

Best regards
Uwe

 drivers/spi/spi-gpio.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/drivers/spi/spi-gpio.c b/drivers/spi/spi-gpio.c
index 0094c64..0b56cfc 100644
--- a/drivers/spi/spi-gpio.c
+++ b/drivers/spi/spi-gpio.c
@@ -235,7 +235,8 @@ static int spi_gpio_setup(struct spi_device *spi)
 			status = gpio_request(cs, dev_name(&spi->dev));
 			if (status)
 				return status;
-			status = gpio_direction_output(cs, spi->mode & SPI_CS_HIGH);
+			status = gpio_direction_output(cs,
+					!(spi->mode & SPI_CS_HIGH));
 		}
 	}
 	if (!status)
-- 
1.7.9


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