Input: synaptics-rmi4 - add device tree support to the SPI transport driver

Add devicetree binding for SPI devices.

Signed-off-by: Andrew Duggan <aduggan@synaptics.com>
Acked-by: Rob Herring <robh@kernel.org>
Tested-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

1 files changed, 57 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/input/rmi4/rmi_spi.txt b/Documentation/devicetree/bindings/input/rmi4/rmi_spi.txt
new file mode 100644
index 000000000000..a4ca7828f21d
--- /dev/null
+++ b/Documentation/devicetree/bindings/input/rmi4/rmi_spi.txt
@@ -0,0 +1,57 @@
+Synaptics RMI4 SPI Device Binding
+
+The Synaptics RMI4 core is able to support RMI4 devices using different
+transports and different functions. This file describes the device tree
+bindings for devices using the SPI transport driver. Complete documentation
+for other transports and functions can be found in
+Documentation/devicetree/bindings/input/rmi4.
+
+Required Properties:
+- compatible: syna,rmi4-spi
+- reg: Chip select address for the device
+- #address-cells: Set to 1 to indicate that the function child nodes
+                    consist of only on uint32 value.
+- #size-cells: Set to 0 to indicate that the function child nodes do not
+                have a size property.
+
+Optional Properties:
+- interrupts: interrupt which the rmi device is connected to.
+- interrupt-parent: The interrupt controller.
+See Documentation/devicetree/bindings/interrupt-controller/interrupts.txt
+
+- spi-rx-delay-us: microsecond delay after a read transfer.
+- spi-tx-delay-us: microsecond delay after a write transfer.
+
+Function Parameters:
+Parameters specific to RMI functions are contained in child nodes of the rmi device
+ node. Documentation for the parameters of each function can be found in:
+Documentation/devicetree/bindings/input/rmi4/rmi_f*.txt.
+
+
+
+Example:
+        spi@7000d800 {
+                rmi4-spi-dev@0 {
+                        compatible = "syna,rmi4-spi";
+                        reg = <0x0>;
+                        #address-cells = <1>;
+                        #size-cells = <0>;
+                        spi-max-frequency = <4000000>;
+                        spi-cpha;
+                        spi-cpol;
+                        interrupt-parent = <&gpio>;
+                        interrupts = <TEGRA_GPIO(K, 2) 0x2>;
+                        spi-rx-delay-us = <30>;
+
+                        rmi4-f01@1 {
+                                reg = <0x1>;
+                                syna,nosleep-mode = <1>;
+                        };
+
+                        rmi4-f11@11 {
+                                reg = <0x11>;
+                                touchscreen-inverted-y;
+                                syna,sensor-type = <2>;
+                        };
+                };
+        };