[PATCH 03/15] dt-bindings: olpc,xo1.75-ec: Add OLPC XO-1.75 EC bindings
From: robh@kernel.org (Rob Herring)
Date: 2018-10-17 19:38:17
Also in:
linux-devicetree, linux-pm, linux-spi, lkml, platform-driver-x86
On Wed, Oct 10, 2018 at 07:22:48PM +0200, Lubomir Rintel wrote:
quoted hunk ↗ jump to hunk
The OLPC XO-1.75 Embedded Controller is a SPI master that uses extra signals for handshaking. It needs to know when is the slave (Linux) side's TX FIFO ready for transfer (the ready-gpio signal on the SPI controller node) and when does it wish to respond with a command (the cmd-gpio property). Signed-off-by: Lubomir Rintel <lkundrak@v3.sk> --- .../bindings/misc/olpc,xo1.75-ec.txt | 24 +++++++++++++++++++ 1 file changed, 24 insertions(+) create mode 100644 Documentation/devicetree/bindings/misc/olpc,xo1.75-ec.txtdiff --git a/Documentation/devicetree/bindings/misc/olpc,xo1.75-ec.txt b/Documentation/devicetree/bindings/misc/olpc,xo1.75-ec.txt new file mode 100644 index 000000000000..14385fee65d2 --- /dev/null +++ b/Documentation/devicetree/bindings/misc/olpc,xo1.75-ec.txt@@ -0,0 +1,24 @@ +OLPC XO-1.75 Embedded Controller + +Required properties: +- compatible: Should be "olpc,xo1.75-ec". +- cmd-gpio: gpio specifier of the CMD pin
cmd-gpios
+ +The embedded controller requires the SPI controller driver to signal readiness +to receive a transfer (that is, when TX FIFO contains the response data) by +strobing the ACK pin with the ready signal. See the "ready-gpio" property of the
This will need updating based on the SPI binding.
+SSP binding as documented in:
+<Documentation/devicetree/bindings/spi/spi-pxa2xx.txt>.
+
+Example:
+ &ssp3 {
+ spi-slave;
+ status = "okay";Don't show status in examples.
+ ready-gpio = <&gpio 125 GPIO_ACTIVE_HIGH>;
+
+ slave {
+ compatible = "olpc,xo1.75-ec";
+ spi-cpha;
+ cmd-gpio = <&gpio 155 GPIO_ACTIVE_HIGH>;
+ };
+ };
--
2.19.0