From: Georgi Vlaev <gvl...@juniper.net>
Add device tree bindings document for the GPIO driver of
Juniper's SAM FPGA.
Signed-off-by: Georgi Vlaev <gvl...@juniper.net>
[Ported from Juniper kernel]
Signed-off-by: Pantelis Antoniou <pantelis.anton...@konsulko.com>
---
.../devicetree/bindings/gpio/jnx,gpio-sam.txt | 110 +++++++++++++++++++++
1 file changed, 110 insertions(+)
create mode 100644 Documentation/devicetree/bindings/gpio/jnx,gpio-sam.txt
diff --git a/Documentation/devicetree/bindings/gpio/jnx,gpio-sam.txt
b/Documentation/devicetree/bindings/gpio/jnx,gpio-sam.txt
new file mode 100644
index 0000000..514c350
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/jnx,gpio-sam.txt
@@ -0,0 +1,110 @@
+Juniper SAM FPGA GPIO block
+
+The controller's registers are organized as sets of eight 32-bit
+registers with each set controlling a bank of up to 32 pins. A single
+interrupt is shared for all of the banks handled by the controller.
+
+Required properties:
+
+- compatible:
+ Must be "jnx,gpio-sam"
+
+- #gpio-cells:
+ Should be <2>. The first cell is the pin number (within the controller's
+ pin space), and the second is used for the following flags:
+ bit[0]: direction (0 = out, 1 = in)
+ bit[1]: init high
+ bit[2]: active low
+ bit[3]: open drain
+ bit[4]: open drain
+
+- gpio-controller:
+ Specifies that the node is a GPIO controller.
+
+Optional properties:
+
+- reg:
+ This driver is part of the SAM FPGA MFD driver, so the
+ address range is supplied by that driver. However you can
+ override using this property.
+
+- gpio-base:
+ Base of the GPIO pins of this instance. If not present use system
allocated.
+
+- gpio-count:
+ Number of GPIO pins of this instance. If not present read the number from
+ the one configured in the FPGA data. Maximum number is 512.
+
+- #interrupt-cells:
+ Should be <2>. The first cell is the GPIO number, the second should
specify
+ flags. The following subset of flags is supported:
+ - bits[16,4:0] trigger type and level flags
+ bit 0: rising edge interrupt
+ bit 1: falling edge interrupt
+ bit 2: active high interrupt
+ bit 3: active low interrupt
+ bit 4: enable debounce
+ bit 16: signal is active low
+ See also
Documentation/devicetree/bindings/interrupt-controller/interrupts.txt
+
+- gpio-interrupts:
+ A number of triples that define the mapping of interrupt groupsb to a
range of
+ pins. The first cell defines the interrupt group, the second is the start
of
+ the pin range and the third the number of pins in the range.
+
+- gpio-exports:
+ A subnode containing the list of pins that will be exported to user-space.
+ Each subnode contains:
+ Required properties:
+ - pin: The gpio to be exported and the relevant flags.
+ Optional properties:
+ - label: The label to use for export; if not supplied use the node
name.
+
+Example:
+
+gpio20: gpio-sam {
+ compatible = "jnx,gpio-sam";
+ gpio-controller;
+ interrupt-controller;
+ /* 1st cell: gpio pin
+ * 2nd cell: flags (bit mask)
+ * bit 0: rising edge interrupt
+ * bit 1: falling edge interrupt
+ * bit 2: active high interrupt
+ * bit 3: active low interrupt
+ * bit 4: enable debounce
+ * bit 16: signal is active low
+ */
+ #interrupt-cells = <2>;
+ #gpio-cells = <2>;
+ gpio-count = <340>;
+ /* 1st cell: gpio interrupt status bit
+ * 2nd cell: 1st pin
+ * 3rd cell: # of pins
+ */
+ gpio-interrupts =
+ <0 0 32>, /* TL / TQ */
+ <1 32 32>, /* PIC 1 */
+ <2 32 32>, /* PIC 1 spare */
+ <7 148 32>, /* PIC 0 */
+ <8 170 32>, /* PIC 0 spare */
+ <16 318 22>; /* FPC */
+
+ gpio-exports {
+ /*
+ * flags:
+ * GPIOF_DIR_IN bit 0=1
+ * GPIOF_DIR_OUT bit 0=0
+ * GPIOF_INIT_HIGH bit 1=1
+ * GPIOF_INIT_HIGH is raw, not translated
+ * GPIOF_ACTIVE_LOW bit 2=1
+ * GPIOF_OPEN_DRAIN bit 3=1
+ * GPIOF_OPEN_SOURCE bit 4=1
+ * GPIOF_EXPORT bit 5=1
+ * GPIOF_EXPORT_CHANGEABLE bit 6=1
+ */
+ tl0-rst {
+ pin = < 8 0x24 >;
+ };
+ };
+};
--
1.9.1
