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authorLinus Torvalds <torvalds@linux-foundation.org>2013-11-12 15:50:46 +0900
committerLinus Torvalds <torvalds@linux-foundation.org>2013-11-12 15:50:46 +0900
commitc2d33069915d1f9b3b1dcc2199af11d4e072b037 (patch)
tree2664fd3c41c2f3223cfbb64793c2ddb8e9087ded /Documentation/devicetree
parent8a5dc585d50015af9c079ae2d182dc4c1cd22914 (diff)
parent993571273275bfecb5161806796eb368db234106 (diff)
Merge tag 'gpio-v3.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio
Pull GPIO changes from Linus Walleij: "Here is the bulk of GPIO changes for the v3.13 development cycle. I've got ACKs for the things that affect other subsystems (or it's my own subsystem, like pinctrl). Most of that pertain to an attempt from my side to consolidate and get rid of custom GPIO implementations in the ARM tree. I will continue doing this. The main change this time is the new GPIO descriptor API, background for this can be found in Corbet's summary from this january in LWN: http://lwn.net/Articles/533632/ Summary: - Merged the GPIO descriptor API from Alexandre Courbot. This is a first step toward trying to get rid of the global GPIO numberspace for the future. - Add an API so that driver can flag that a certain GPIO line is being used by a irqchip backend for generating IRQs, so that we can enforce checks, like not allowing users to switch that line to an output at runtime, since this makes no sense. Implemented corresponding calls in a few select drivers. - ACPI GPIO cleanups, refactorings and switch to using the descriptor-based interface. - Support for the TPS80036 Palmas GPIO variant. - A new driver for the Broadcom Kona GPIO SoC IP block. - Device tree support for the PCF857x driver. - A set of ARM GPIO refactorings with the goal of getting rid of a bunch of custom GPIO implementations from the arch/arm/* tree: * Move the IOP GPIO driver to the GPIO subsystem and fix all users to use the gpiolib API for accessing GPIOs. Delete the old custom GPIO implementation. * Delete the unused custom PXA GPIO implemention. * Convert all users of the IXP4 custom GPIO implementation to use gpiolib and delete the custom implementation. * Delete the custom Gemini GPIO implementation, also completely unused. - Various cleanups and renamings" * tag 'gpio-v3.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (85 commits) gpio: gpio-mxs: Remove unneeded dt checks gpio: pl061: don't depend on CONFIG_ARM gpio: bcm-kona: add missing .owner to struct gpio_chip gpiolib: provide a declaration of seq_file in gpio/driver.h gpiolib: include gpio/consumer.h in of_gpio.h for desc_to_gpio() gpio: provide stubs for devres gpio functions gpiolib: devres: add missing headers gpiolib: make GPIO_DEVRES depend on GPIOLIB gpiolib: devres: fix devm_gpiod_get_index() gpiolib / ACPI: document the GPIO descriptor based interface gpiolib / ACPI: allow passing GPIOF_ACTIVE_LOW for GpioInt resources gpiolib / ACPI: add ACPI support for gpiod_get_index() gpiolib / ACPI: convert to gpiod interfaces gpiolib: add gpiod_get() and gpiod_put() functions gpiolib: port of_ functions to use gpiod gpiolib: export descriptor-based GPIO interface Fixup "MAINTAINERS: GPIO-INTEL-MID: add maintainer" gpio: bcm281xx: Don't print addresses of GPIO area in probe() gpio: tegra: use new gpio_lock_as_irq() API gpio: rcar: Include linux/of.h header ...
Diffstat (limited to 'Documentation/devicetree')
-rw-r--r--Documentation/devicetree/bindings/gpio/gpio-bcm-kona.txt52
-rw-r--r--Documentation/devicetree/bindings/gpio/gpio-pcf857x.txt71
2 files changed, 123 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/gpio/gpio-bcm-kona.txt b/Documentation/devicetree/bindings/gpio/gpio-bcm-kona.txt
new file mode 100644
index 000000000000..4a63bc96b687
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/gpio-bcm-kona.txt
@@ -0,0 +1,52 @@
+Broadcom Kona Family GPIO
+=========================
+
+This GPIO driver is used in the following Broadcom SoCs:
+ BCM11130, BCM11140, BCM11351, BCM28145, BCM28155
+
+The Broadcom GPIO Controller IP can be configured prior to synthesis to
+support up to 8 banks of 32 GPIOs where each bank has its own IRQ. The
+GPIO controller only supports edge, not level, triggering of interrupts.
+
+Required properties
+-------------------
+
+- compatible: "brcm,bcm11351-gpio", "brcm,kona-gpio"
+- reg: Physical base address and length of the controller's registers.
+- interrupts: The interrupt outputs from the controller. There is one GPIO
+ interrupt per GPIO bank. The number of interrupts listed depends on the
+ number of GPIO banks on the SoC. The interrupts must be ordered by bank,
+ starting with bank 0. There is always a 1:1 mapping between banks and
+ IRQs.
+- #gpio-cells: Should be <2>. The first cell is the pin number, the second
+ cell is used to specify optional parameters:
+ - bit 0 specifies polarity (0 for normal, 1 for inverted)
+ See also "gpio-specifier" in .../devicetree/bindings/gpio/gpio.txt.
+- #interrupt-cells: Should be <2>. The first cell is the GPIO number. The
+ second cell is used to specify flags. The following subset of flags is
+ supported:
+ - trigger type (bits[1:0]):
+ 1 = low-to-high edge triggered.
+ 2 = high-to-low edge triggered.
+ 3 = low-to-high or high-to-low edge triggered
+ Valid values are 1, 2, 3
+ See also .../devicetree/bindings/interrupt-controller/interrupts.txt.
+- gpio-controller: Marks the device node as a GPIO controller.
+- interrupt-controller: Marks the device node as an interrupt controller.
+
+Example:
+ gpio: gpio@35003000 {
+ compatible = "brcm,bcm11351-gpio", "brcm,kona-gpio";
+ reg = <0x35003000 0x800>;
+ interrupts =
+ <GIC_SPI 106 IRQ_TYPE_LEVEL_HIGH
+ GIC_SPI 115 IRQ_TYPE_LEVEL_HIGH
+ GIC_SPI 114 IRQ_TYPE_LEVEL_HIGH
+ GIC_SPI 113 IRQ_TYPE_LEVEL_HIGH
+ GIC_SPI 112 IRQ_TYPE_LEVEL_HIGH
+ GIC_SPI 111 IRQ_TYPE_LEVEL_HIGH>;
+ #gpio-cells = <2>;
+ #interrupt-cells = <2>;
+ gpio-controller;
+ interrupt-controller;
+ };
diff --git a/Documentation/devicetree/bindings/gpio/gpio-pcf857x.txt b/Documentation/devicetree/bindings/gpio/gpio-pcf857x.txt
new file mode 100644
index 000000000000..d63194a2c848
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/gpio-pcf857x.txt
@@ -0,0 +1,71 @@
+* 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
+ - "ti,tca9554": For the TI TCA9554
+
+ - 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 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.
+ - interrupt-parent: phandle of the parent interrupt controller.
+ - 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>;
+ };

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