summaryrefslogtreecommitdiffstats
path: root/dts/Bindings/gpio/gpio-pcf857x.txt
diff options
context:
space:
mode:
Diffstat (limited to 'dts/Bindings/gpio/gpio-pcf857x.txt')
-rw-r--r--dts/Bindings/gpio/gpio-pcf857x.txt69
1 files changed, 0 insertions, 69 deletions
diff --git a/dts/Bindings/gpio/gpio-pcf857x.txt b/dts/Bindings/gpio/gpio-pcf857x.txt
deleted file mode 100644
index a482455a20..0000000000
--- a/dts/Bindings/gpio/gpio-pcf857x.txt
+++ /dev/null
@@ -1,69 +0,0 @@
-* PCF857x-compatible I/O expanders
-
-The PCF857x-compatible chips have "quasi-bidirectional" I/O lines that can be
-driven high by a pull-up current source or driven low to ground. This combines
-the direction and output level into a single bit per line, which can't be read
-back. We can't actually know at initialization time whether a line is configured
-(a) as output and driving the signal low/high, or (b) as input and reporting a
-low/high value, without knowing the last value written since the chip came out
-of reset (if any). The only reliable solution for setting up line direction is
-thus to do it explicitly.
-
-Required Properties:
-
- - compatible: should be one of the following.
- - "maxim,max7328": For the Maxim MAX7378
- - "maxim,max7329": For the Maxim MAX7329
- - "nxp,pca8574": For the NXP PCA8574
- - "nxp,pca8575": For the NXP PCA8575
- - "nxp,pca9670": For the NXP PCA9670
- - "nxp,pca9671": For the NXP PCA9671
- - "nxp,pca9672": For the NXP PCA9672
- - "nxp,pca9673": For the NXP PCA9673
- - "nxp,pca9674": For the NXP PCA9674
- - "nxp,pca9675": For the NXP PCA9675
- - "nxp,pcf8574": For the NXP PCF8574
- - "nxp,pcf8574a": For the NXP PCF8574A
- - "nxp,pcf8575": For the NXP PCF8575
-
- - reg: I2C slave address.
-
- - gpio-controller: Marks the device node as a gpio controller.
- - #gpio-cells: Should be 2. The first cell is the GPIO number and the second
- cell specifies GPIO flags, as defined in <dt-bindings/gpio/gpio.h>. Only the
- GPIO_ACTIVE_HIGH and GPIO_ACTIVE_LOW flags are supported.
-
-Optional Properties:
-
- - lines-initial-states: Bitmask that specifies the initial state of each
- line. When a bit is set to zero, the corresponding line will be initialized to
- the input (pulled-up) state. When the bit is set to one, the line will be
- initialized the low-level output state. If the property is not specified
- all lines will be initialized to the input state.
-
- The I/O expander can detect input state changes, and thus optionally act as
- an interrupt controller. When the expander interrupt line is connected all the
- following properties must be set. For more information please see the
- interrupt controller device tree bindings documentation available at
- Documentation/devicetree/bindings/interrupt-controller/interrupts.txt.
-
- - interrupt-controller: Identifies the node as an interrupt controller.
- - #interrupt-cells: Number of cells to encode an interrupt source, shall be 2.
- - interrupts: Interrupt specifier for the controllers interrupt.
-
-
-Please refer to gpio.txt in this directory for details of the common GPIO
-bindings used by client devices.
-
-Example: PCF8575 I/O expander node
-
- pcf8575: gpio@20 {
- compatible = "nxp,pcf8575";
- reg = <0x20>;
- interrupt-parent = <&irqpin2>;
- interrupts = <3 0>;
- gpio-controller;
- #gpio-cells = <2>;
- interrupt-controller;
- #interrupt-cells = <2>;
- };