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-rw-r--r--Documentation/devicetree/bindings/gpio/gpio-mpc8xxx.txt8
-rw-r--r--Documentation/devicetree/bindings/gpio/gpio-msm.txt26
-rw-r--r--Documentation/devicetree/bindings/gpio/gpio-pca953x.txt1
-rw-r--r--Documentation/devicetree/bindings/gpio/gpio-zynq.txt9
-rw-r--r--Documentation/devicetree/bindings/gpio/gpio.txt41
-rw-r--r--Documentation/devicetree/bindings/gpio/netxbig-gpio-ext.txt22
6 files changed, 77 insertions, 30 deletions
diff --git a/Documentation/devicetree/bindings/gpio/gpio-mpc8xxx.txt b/Documentation/devicetree/bindings/gpio/gpio-mpc8xxx.txt
index 805ddcd79..120bc4971 100644
--- a/Documentation/devicetree/bindings/gpio/gpio-mpc8xxx.txt
+++ b/Documentation/devicetree/bindings/gpio/gpio-mpc8xxx.txt
@@ -1,9 +1,9 @@
-* Freescale MPC512x/MPC8xxx GPIO controller
+* Freescale MPC512x/MPC8xxx/Layerscape GPIO controller
Required properties:
- compatible : Should be "fsl,<soc>-gpio"
The following <soc>s are known to be supported:
- mpc5121, mpc5125, mpc8349, mpc8572, mpc8610, pq3, qoriq
+ mpc5121, mpc5125, mpc8349, mpc8572, mpc8610, pq3, qoriq.
- reg : Address and length of the register set for the device
- interrupts : Should be the port interrupt shared by all 32 pins.
- #gpio-cells : Should be two. The first cell is the pin number and
@@ -11,6 +11,10 @@ Required properties:
0 = active high
1 = active low
+Optional properties:
+- little-endian : GPIO registers are used as little endian. If not
+ present registers are used as big endian by default.
+
Example:
gpio0: gpio@1100 {
diff --git a/Documentation/devicetree/bindings/gpio/gpio-msm.txt b/Documentation/devicetree/bindings/gpio/gpio-msm.txt
deleted file mode 100644
index ac20e68a0..000000000
--- a/Documentation/devicetree/bindings/gpio/gpio-msm.txt
+++ /dev/null
@@ -1,26 +0,0 @@
-MSM GPIO controller bindings
-
-Required properties:
-- compatible:
- - "qcom,msm-gpio" for MSM controllers
-- #gpio-cells : Should be two.
- - first cell is the pin number
- - second cell is used to specify optional parameters (unused)
-- gpio-controller : Marks the device node as a GPIO controller.
-- #interrupt-cells : Should be 2.
-- interrupt-controller: Mark the device node as an interrupt controller
-- interrupts : Specify the TLMM summary interrupt number
-- ngpio : Specify the number of MSM GPIOs
-
-Example:
-
- msmgpio: gpio@fd510000 {
- compatible = "qcom,msm-gpio";
- gpio-controller;
- #gpio-cells = <2>;
- interrupt-controller;
- #interrupt-cells = <2>;
- reg = <0xfd510000 0x4000>;
- interrupts = <0 208 0>;
- ngpio = <150>;
- };
diff --git a/Documentation/devicetree/bindings/gpio/gpio-pca953x.txt b/Documentation/devicetree/bindings/gpio/gpio-pca953x.txt
index b9a42f294..13df9933f 100644
--- a/Documentation/devicetree/bindings/gpio/gpio-pca953x.txt
+++ b/Documentation/devicetree/bindings/gpio/gpio-pca953x.txt
@@ -24,6 +24,7 @@ Required properties:
ti,tca6408
ti,tca6416
ti,tca6424
+ ti,tca9539
exar,xra1202
Example:
diff --git a/Documentation/devicetree/bindings/gpio/gpio-zynq.txt b/Documentation/devicetree/bindings/gpio/gpio-zynq.txt
index db4c6a663..7b542657f 100644
--- a/Documentation/devicetree/bindings/gpio/gpio-zynq.txt
+++ b/Documentation/devicetree/bindings/gpio/gpio-zynq.txt
@@ -12,6 +12,13 @@ Required properties:
- interrupts : Interrupt specifier (see interrupt bindings for
details)
- interrupt-parent : Must be core interrupt controller
+- interrupt-controller : Marks the device node as an interrupt controller.
+- #interrupt-cells : Should be 2. The first cell is the GPIO number.
+ The second cell bits[3:0] is used to specify trigger type and level flags:
+ 1 = low-to-high edge triggered.
+ 2 = high-to-low edge triggered.
+ 4 = active high level-sensitive.
+ 8 = active low level-sensitive.
- reg : Address and length of the register set for the device
Example:
@@ -22,5 +29,7 @@ Example:
gpio-controller;
interrupt-parent = <&intc>;
interrupts = <0 20 4>;
+ interrupt-controller;
+ #interrupt-cells = <2>;
reg = <0xe000a000 0x1000>;
};
diff --git a/Documentation/devicetree/bindings/gpio/gpio.txt b/Documentation/devicetree/bindings/gpio/gpio.txt
index 82d40e250..069cdf6f9 100644
--- a/Documentation/devicetree/bindings/gpio/gpio.txt
+++ b/Documentation/devicetree/bindings/gpio/gpio.txt
@@ -54,9 +54,13 @@ only uses one.
gpio-specifier may encode: bank, pin position inside the bank,
whether pin is open-drain and whether pin is logically inverted.
+
Exact meaning of each specifier cell is controller specific, and must
-be documented in the device tree binding for the device. Use the macros
-defined in include/dt-bindings/gpio/gpio.h whenever possible:
+be documented in the device tree binding for the device.
+
+Most controllers are however specifying a generic flag bitfield
+in the last cell, so for these, use the macros defined in
+include/dt-bindings/gpio/gpio.h whenever possible:
Example of a node using GPIOs:
@@ -67,6 +71,15 @@ Example of a node using GPIOs:
GPIO_ACTIVE_HIGH is 0, so in this example gpio-specifier is "18 0" and encodes
GPIO pin number, and GPIO flags as accepted by the "qe_pio_e" gpio-controller.
+Optional standard bitfield specifiers for the last cell:
+
+- Bit 0: 0 means active high, 1 means active low
+- Bit 1: 1 means single-ended wiring, see:
+ https://en.wikipedia.org/wiki/Single-ended_triode
+ When used with active-low, this means open drain/collector, see:
+ https://en.wikipedia.org/wiki/Open_collector
+ When used with active-high, this means open source/emitter
+
1.1) GPIO specifier best practices
----------------------------------
@@ -118,6 +131,30 @@ Every GPIO controller node must contain both an empty "gpio-controller"
property, and a #gpio-cells integer property, which indicates the number of
cells in a gpio-specifier.
+Optionally, a GPIO controller may have a "ngpios" property. This property
+indicates the number of in-use slots of available slots for GPIOs. The
+typical example is something like this: the hardware register is 32 bits
+wide, but only 18 of the bits have a physical counterpart. The driver is
+generally written so that all 32 bits can be used, but the IP block is reused
+in a lot of designs, some using all 32 bits, some using 18 and some using
+12. In this case, setting "ngpios = <18>;" informs the driver that only the
+first 18 GPIOs, at local offset 0 .. 17, are in use.
+
+If these GPIOs do not happen to be the first N GPIOs at offset 0...N-1, an
+additional bitmask is needed to specify which GPIOs are actually in use,
+and which are dummies. The bindings for this case has not yet been
+specified, but should be specified if/when such hardware appears.
+
+Example:
+
+gpio-controller@00000000 {
+ compatible = "foo";
+ reg = <0x00000000 0x1000>;
+ gpio-controller;
+ #gpio-cells = <2>;
+ ngpios = <18>;
+}
+
The GPIO chip may contain GPIO hog definitions. GPIO hogging is a mechanism
providing automatic GPIO request and configuration as part of the
gpio-controller's driver probe function.
diff --git a/Documentation/devicetree/bindings/gpio/netxbig-gpio-ext.txt b/Documentation/devicetree/bindings/gpio/netxbig-gpio-ext.txt
new file mode 100644
index 000000000..50ec2e690
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/netxbig-gpio-ext.txt
@@ -0,0 +1,22 @@
+Binding for the GPIO extension bus found on some LaCie/Seagate boards
+(Example: 2Big/5Big Network v2, 2Big NAS).
+
+Required properties:
+- compatible: "lacie,netxbig-gpio-ext".
+- addr-gpios: GPIOs representing the address register (LSB -> MSB).
+- data-gpios: GPIOs representing the data register (LSB -> MSB).
+- enable-gpio: latches the new configuration (address, data) on raising edge.
+
+Example:
+
+netxbig_gpio_ext: netxbig-gpio-ext {
+ compatible = "lacie,netxbig-gpio-ext";
+
+ addr-gpios = <&gpio1 15 GPIO_ACTIVE_HIGH
+ &gpio1 16 GPIO_ACTIVE_HIGH
+ &gpio1 17 GPIO_ACTIVE_HIGH>;
+ data-gpios = <&gpio1 12 GPIO_ACTIVE_HIGH
+ &gpio1 13 GPIO_ACTIVE_HIGH
+ &gpio1 14 GPIO_ACTIVE_HIGH>;
+ enable-gpio = <&gpio0 29 GPIO_ACTIVE_HIGH>;
+};