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linux/Documentation/devicetree/bindings/gpio/sodaville.txt

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gpio: Add a driver for Sodaville GPIO controller Sodaville has GPIO controller behind the PCI bus. To my suprissed it is not the same as on PXA. The interrupt & gpio chip can be referenced from the device tree like from any other driver. Unfortunately the driver which uses the gpio interrupt has to use irq_of_parse_and_map() instead of platform_get_irq(). The problem is that the platform device (which is created from the device tree) is most likely created before the interrupt chip is registered and therefore irq_of_parse_and_map() fails. In theory the driver works as module. In reality most of the irq functions are not exported to modules and it is possible that _this_ module is unloaded while the provided irqs are still in use. Signed-off-by: Hans J. Koch <hjk@linutronix.de> [torbenh@linutronix.de: make it work after the irq namespace cleanup, add some device tree entries.] Signed-off-by: Torben Hohn <torbenh@linutronix.de> [bigeasy@linutronix.de: convert to generic irq & gpio chip] Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> [grant.likely@secretlab.ca: depend on x86 to avoid irq_domain breakage] Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-06-27 15:26:23 +08:00
GPIO controller on CE4100 / Sodaville SoCs
==========================================
The bindings for CE4100's GPIO controller match the generic description
which is covered by the gpio.txt file in this folder.
The only additional property is the intel,muxctl property which holds the
value which is written into the MUXCNTL register.
There is no compatible property for now because the driver is probed via
PCI id (vendor 0x8086 device 0x2e67).
The interrupt specifier consists of two cells encoded as follows:
- <1st cell>: The interrupt-number that identifies the interrupt source.
- <2nd cell>: The level-sense information, encoded as follows:
4 - active high level-sensitive
8 - active low level-sensitive
Example of the GPIO device and one user:
pcigpio: gpio@b,1 {
/* two cells for GPIO and interrupt */
#gpio-cells = <2>;
#interrupt-cells = <2>;
compatible = "pci8086,2e67.2",
"pci8086,2e67",
"pciclassff0000",
"pciclassff00";
reg = <0x15900 0x0 0x0 0x0 0x0>;
/* Interrupt line of the gpio device */
interrupts = <15 1>;
/* It is an interrupt and GPIO controller itself */
interrupt-controller;
gpio-controller;
intel,muxctl = <0>;
};
testuser@20 {
compatible = "example,testuser";
/* User the 11th GPIO line as an active high triggered
* level interrupt
*/
interrupts = <11 8>;
interrupt-parent = <&pcigpio>;
/* Use this GPIO also with the gpio functions */
gpios = <&pcigpio 11 0>;
};