spi: Make GPIO CSs honour the SPI_NO_CS flag

The SPI configuration state includes an SPI_NO_CS flag that disables
all CS line manipulation, for applications that want to manage their
own chip selects. However, this flag is ignored by the GPIO CS code
in the SPI framework.

Correct this omission with a trivial patch.

Signed-off-by: Phil Elwell <phil@raspberrypi.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index fcbd4cfd28188b55aacc74a1690f77b16f0f9781..ea3e5e146764dafd4afb8037dec5df0a016d093e 100644 (file)
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -775,7 +775,9 @@ static void spi_set_cs(struct spi_device *spi, bool enable)
                enable = !enable;
 
        if (gpio_is_valid(spi->cs_gpio)) {
-               gpio_set_value(spi->cs_gpio, !enable);
+               /* Honour the SPI_NO_CS flag */
+               if (!(spi->mode & SPI_NO_CS))
+                       gpio_set_value(spi->cs_gpio, !enable);
                /* Some SPI masters need both GPIO CS & slave_select */
                if ((spi->controller->flags & SPI_MASTER_GPIO_SS) &&
                    spi->controller->set_cs)