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-rw-r--r--Documentation/acpi/enumeration.txt32
-rw-r--r--Documentation/devicetree/bindings/gpio/gpio-grgpio.txt26
-rw-r--r--Documentation/devicetree/bindings/gpio/gpio-mcp23s08.txt47
-rw-r--r--Documentation/devicetree/bindings/gpio/gpio-omap.txt7
4 files changed, 109 insertions, 3 deletions
diff --git a/Documentation/acpi/enumeration.txt b/Documentation/acpi/enumeration.txt
index 94a656131885..b0d541042ac6 100644
--- a/Documentation/acpi/enumeration.txt
+++ b/Documentation/acpi/enumeration.txt
@@ -199,6 +199,8 @@ the device to the driver. For example:
{
Name (SBUF, ResourceTemplate()
{
+ ...
+ // Used to power on/off the device
GpioIo (Exclusive, PullDefault, 0x0000, 0x0000,
IoRestrictionOutputOnly, "\\_SB.PCI0.GPI0",
0x00, ResourceConsumer,,)
@@ -206,10 +208,20 @@ the device to the driver. For example:
// Pin List
0x0055
}
+
+ // Interrupt for the device
+ GpioInt (Edge, ActiveHigh, ExclusiveAndWake, PullNone,
+ 0x0000, "\\_SB.PCI0.GPI0", 0x00, ResourceConsumer,,)
+ {
+ // Pin list
+ 0x0058
+ }
+
...
- Return (SBUF)
}
+
+ Return (SBUF)
}
These GPIO numbers are controller relative and path "\\_SB.PCI0.GPI0"
@@ -220,6 +232,24 @@ The driver can do this by including <linux/acpi_gpio.h> and then calling
acpi_get_gpio(path, gpio). This will return the Linux GPIO number or
negative errno if there was no translation found.
+In a simple case of just getting the Linux GPIO number from device
+resources one can use acpi_get_gpio_by_index() helper function. It takes
+pointer to the device and index of the GpioIo/GpioInt descriptor in the
+device resources list. For example:
+
+ int gpio_irq, gpio_power;
+ int ret;
+
+ gpio_irq = acpi_get_gpio_by_index(dev, 1, NULL);
+ if (gpio_irq < 0)
+ /* handle error */
+
+ gpio_power = acpi_get_gpio_by_index(dev, 0, NULL);
+ if (gpio_power < 0)
+ /* handle error */
+
+ /* Now we can use the GPIO numbers */
+
Other GpioIo parameters must be converted first by the driver to be
suitable to the gpiolib before passing them.
diff --git a/Documentation/devicetree/bindings/gpio/gpio-grgpio.txt b/Documentation/devicetree/bindings/gpio/gpio-grgpio.txt
new file mode 100644
index 000000000000..e466598105fc
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/gpio-grgpio.txt
@@ -0,0 +1,26 @@
+Aeroflex Gaisler GRGPIO General Purpose I/O cores.
+
+The GRGPIO GPIO core is available in the GRLIB VHDL IP core library.
+
+Note: In the ordinary environment for the GRGPIO core, a Leon SPARC system,
+these properties are built from information in the AMBA plug&play.
+
+Required properties:
+
+- name : Should be "GAISLER_GPIO" or "01_01a"
+
+- reg : Address and length of the register set for the device
+
+- interrupts : Interrupt numbers for this device
+
+Optional properties:
+
+- nbits : The number of gpio lines. If not present driver assumes 32 lines.
+
+- irqmap : An array with an index for each gpio line. An index is either a valid
+ index into the interrupts property array, or 0xffffffff that indicates
+ no irq for that line. Driver provides no interrupt support if not
+ present.
+
+For further information look in the documentation for the GLIB IP core library:
+http://www.gaisler.com/products/grlib/grip.pdf
diff --git a/Documentation/devicetree/bindings/gpio/gpio-mcp23s08.txt b/Documentation/devicetree/bindings/gpio/gpio-mcp23s08.txt
new file mode 100644
index 000000000000..629d0ef17308
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/gpio-mcp23s08.txt
@@ -0,0 +1,47 @@
+Microchip MCP2308/MCP23S08/MCP23017/MCP23S17 driver for
+8-/16-bit I/O expander with serial interface (I2C/SPI)
+
+Required properties:
+- compatible : Should be
+ - "mcp,mcp23s08" for 8 GPIO SPI version
+ - "mcp,mcp23s17" for 16 GPIO SPI version
+ - "mcp,mcp23008" for 8 GPIO I2C version or
+ - "mcp,mcp23017" for 16 GPIO I2C version of the chip
+- #gpio-cells : Should be two.
+ - first cell is the pin number
+ - second cell is used to specify flags. Flags are currently unused.
+- gpio-controller : Marks the device node as a GPIO controller.
+- reg : For an address on its bus. I2C uses this a the I2C address of the chip.
+ SPI uses this to specify the chipselect line which the chip is
+ connected to. The driver and the SPI variant of the chip support
+ multiple chips on the same chipselect. Have a look at
+ mcp,spi-present-mask below.
+
+Required device specific properties (only for SPI chips):
+- mcp,spi-present-mask : This is a present flag, that makes only sense for SPI
+ chips - as the name suggests. Multiple SPI chips can share the same
+ SPI chipselect. Set a bit in bit0-7 in this mask to 1 if there is a
+ chip connected with the corresponding spi address set. For example if
+ you have a chip with address 3 connected, you have to set bit3 to 1,
+ which is 0x08. mcp23s08 chip variant only supports bits 0-3. It is not
+ possible to mix mcp23s08 and mcp23s17 on the same chipselect. Set at
+ least one bit to 1 for SPI chips.
+- spi-max-frequency = The maximum frequency this chip is able to handle
+
+Example I2C:
+gpiom1: gpio@20 {
+ compatible = "mcp,mcp23017";
+ gpio-controller;
+ #gpio-cells = <2>;
+ reg = <0x20>;
+};
+
+Example SPI:
+gpiom1: gpio@0 {
+ compatible = "mcp,mcp23s17";
+ gpio-controller;
+ #gpio-cells = <2>;
+ spi-present-mask = <0x01>;
+ reg = <0>;
+ spi-max-frequency = <1000000>;
+};
diff --git a/Documentation/devicetree/bindings/gpio/gpio-omap.txt b/Documentation/devicetree/bindings/gpio/gpio-omap.txt
index bff51a2fee1e..1b524c0c79fe 100644
--- a/Documentation/devicetree/bindings/gpio/gpio-omap.txt
+++ b/Documentation/devicetree/bindings/gpio/gpio-omap.txt
@@ -20,8 +20,11 @@ Required properties:
8 = active low level-sensitive.
OMAP specific properties:
-- ti,hwmods: Name of the hwmod associated to the GPIO:
- "gpio<X>", <X> being the 1-based instance number from the HW spec
+- ti,hwmods: Name of the hwmod associated to the GPIO:
+ "gpio<X>", <X> being the 1-based instance number
+ from the HW spec.
+- ti,gpio-always-on: Indicates if a GPIO bank is always powered and
+ so will never lose its logic state.
Example: