Merge remote-tracking branch 'gpio/for-next'

2 files changed, 33 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/gpio/gpio-thunderx.txt b/Documentation/devicetree/bindings/gpio/gpio-thunderx.txt
new file mode 100644
index 000000000000..3f883ae29d11
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/gpio-thunderx.txt
@@ -0,0 +1,27 @@
+Cavium ThunderX/OCTEON-TX GPIO controller bindings
+
+Required Properties:
+- reg: The controller bus address.
+- gpio-controller: Marks the device node as a GPIO controller.
+- #gpio-cells: Must be 2.
+  - First cell is the GPIO pin number relative to the controller.
+  - Second cell is a standard generic flag bitfield as described in gpio.txt.
+
+Optional Properties:
+- compatible: "cavium,thunder-8890-gpio", unused as PCI driver binding is used.
+- interrupt-controller: Marks the device node as an interrupt controller.
+- #interrupt-cells: Must be present and have value of 2 if
+                    "interrupt-controller" is present.
+  - First cell is the GPIO pin number relative to the controller.
+  - Second cell is triggering flags as defined in interrupts.txt.
+
+Example:
+
+gpio_6_0: gpio@6,0 {
+	compatible = "cavium,thunder-8890-gpio";
+	reg = <0x3000 0 0 0 0>; /*  DEVFN = 0x30 (6:0) */
+	gpio-controller;
+	#gpio-cells = <2>;
+	interrupt-controller;
+	#interrupt-cells = <2>;
+};
diff --git a/Documentation/gpio/consumer.txt b/Documentation/gpio/consumer.txt
index 05676fdacfe3..912568baabb9 100644
--- a/Documentation/gpio/consumer.txt
+++ b/Documentation/gpio/consumer.txt
@@ -70,6 +70,12 @@ instead of -ENOENT if no GPIO has been assigned to the requested function:
 						   unsigned int index,
 						   enum gpiod_flags flags)
 
+Note that gpio_get*_optional() functions (and their managed variants), unlike
+the rest of gpiolib API, also return NULL when gpiolib support is disabled.
+This is helpful to driver authors, since they do not need to special case
+-ENOSYS return codes.  System integrators should however be careful to enable
+gpiolib on systems that need it.
+
 For a function using multiple GPIOs all of those can be obtained with one call:
 
 	struct gpio_descs *gpiod_get_array(struct device *dev,