From: Lars-Peter Clausen Date: Thu, 6 Dec 2012 15:55:33 +0000 (+0100) Subject: spi: Add support for specifying 3-wire mode via device tree X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=c20151dff8a6d503c0d0cc4387c33a618cdabcb7;p=linux-beck.git spi: Add support for specifying 3-wire mode via device tree This patch allows to specify that a SPI device is connected in 3-wire mode via device tree. Signed-off-by: Lars-Peter Clausen Acked-by: Rob Herring Signed-off-by: Grant Likely --- diff --git a/Documentation/devicetree/bindings/spi/spi-bus.txt b/Documentation/devicetree/bindings/spi/spi-bus.txt index 77a8b0d39b54..296015e3c632 100644 --- a/Documentation/devicetree/bindings/spi/spi-bus.txt +++ b/Documentation/devicetree/bindings/spi/spi-bus.txt @@ -53,6 +53,8 @@ contain the following properties. shifted clock phase (CPHA) mode - spi-cs-high - (optional) Empty property indicating device requires chip select active high +- spi-3wire - (optional) Empty property indicating device requires + 3-wire mode. If a gpio chipselect is used for the SPI slave the gpio number will be passed via the cs_gpio diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index b370d292d19c..2ca5f079ff01 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -861,6 +861,8 @@ static void of_register_spi_devices(struct spi_master *master) spi->mode |= SPI_CPOL; if (of_find_property(nc, "spi-cs-high", NULL)) spi->mode |= SPI_CS_HIGH; + if (of_find_property(nc, "spi-3wire", NULL)) + spi->mode |= SPI_3WIRE; /* Device speed */ prop = of_get_property(nc, "spi-max-frequency", &len);