GPIOHANDLE_SET_CONFIG_IOCTL

Warning

This ioctl is part of GPIO Character Device Userspace API (v1) and is obsoleted by GPIO_V2_LINE_SET_CONFIG_IOCTL.

Name

GPIOHANDLE_SET_CONFIG_IOCTL - Update the configuration of previously requested lines.

Synopsis

GPIOHANDLE_SET_CONFIG_IOCTL

int ioctl(int handle_fd, GPIOHANDLE_SET_CONFIG_IOCTL, struct gpiohandle_config *config)

Arguments

handle_fd

The file descriptor of the GPIO character device, as returned in the request.fd by GPIO_GET_LINEHANDLE_IOCTL.

config

The new configuration to apply to the requested lines.

Description

Update the configuration of previously requested lines, without releasing the line or introducing potential glitches.

The configuration applies to all requested lines.

The same Configuration Rules and Configuration Support that apply when requesting the lines also apply when updating the line configuration, with the additional restriction that a direction flag must be set. Requesting an invalid configuration, including without a direction flag set, is an error (EINVAL).

The motivating use case for this command is changing direction of bi-directional lines between input and output, but it may be used more generally to move lines seamlessly from one configuration state to another.

To only change the value of output lines, use GPIO_HANDLE_SET_LINE_VALUES_IOCTL.

First added in 5.5.

Return Value

On success 0.

On error -1 and the errno variable is set appropriately. Common error codes are described in GPIO Error Codes.