[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Wed, 10 Oct 2018 19:22:48 +0200
From: Lubomir Rintel <lkundrak@...sk>
To: Mark Brown <broonie@...nel.org>,
Geert Uytterhoeven <geert+renesas@...der.be>,
Darren Hart <dvhart@...radead.org>,
Andy Shevchenko <andy@...radead.org>
Cc: Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
James Cameron <quozl@...top.org>,
Sebastian Reichel <sre@...nel.org>,
Rob Herring <robh+dt@...nel.org>,
Mark Rutland <mark.rutland@....com>,
Eric Miao <eric.y.miao@...il.com>,
Haojian Zhuang <haojian.zhuang@...il.com>,
Daniel Mack <daniel@...que.org>,
Robert Jarzmik <robert.jarzmik@...e.fr>,
linux-spi@...r.kernel.org, devicetree@...r.kernel.org,
linux-kernel@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
platform-driver-x86@...r.kernel.org, devel@...verdev.osuosl.org,
linux-pm@...r.kernel.org, Lubomir Rintel <lkundrak@...sk>
Subject: [PATCH 03/15] dt-bindings: olpc,xo1.75-ec: Add OLPC XO-1.75 EC bindings
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@...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.txt
diff --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
+
+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
+SSP binding as documented in:
+<Documentation/devicetree/bindings/spi/spi-pxa2xx.txt>.
+
+Example:
+ &ssp3 {
+ spi-slave;
+ status = "okay";
+ 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
Powered by blists - more mailing lists