page_type	description	languages	products
sample	Illustrates how to write a GPIO controller driver that works in conjunction with the GPIO framework extension (GpioClx).	cpp	windows windows-wdk

GPIO Sample Drivers

The GPIO samples contain annotated code to illustrate how to write a GPIO controller driver that works in conjunction with the GPIO framework extension (GpioClx) to handle GPIO I/O control requests, and a peripheral driver that runs in kernel mode and uses GPIO resources.

The GPIO sample set contains the following samples:

Minifilter	Sample description
SimGpio	The files in this sample contain the source code for a GPIO controller driver that communicates with GpioClx through the GpioClx device driver interface (DDI). The GPIO controller driver is written for a hypothetical memory-mapped GPIO controller (simgpio). The code is meant to be purely instructional. An ASL file illustrates how to specify a GPIO interrupt and I/O descriptor in the ACPI firmware.
SimGpio_I2C	The files in this sample contain the source code for a GPIO controller driver that communicates with GpioClx through the GpioClx DDI. In contrast to the SimGpio sample, the GPIO controller in this sample is not memory-mapped. The GPIO controller driver is written for a hypothetical GPIO controller that resides on an I2C bus (simgpio_i2c). The code is meant to be purely instructional. An ASL file illustrates how to specify a GPIO interrupt and I/O descriptor in the ACPI firmware.
SimDevice\kmdf	The purpose of this sample is to show how a driver opens a device and performs I/O operations on a GPIO controller in kernel mode. Additionally, this sample demonstrates how the driver connects to a GPIO interrupt resource. The ASL file illustrates how to specify a GPIO interrupt and I/O descriptor in the ACPI firmware.
SimDevice\umdf	The purpose of this sample is to show how a driver opens a device and performs I/O operations on a GPIO controller in user mode. Additionally, this sample demonstrates how the driver connects to a GPIO interrupt resource. The ASL file illustrates how to specify a GPIO interrupt and I/O descriptor in the ACPI firmware.