55 lines
1.2 KiB
ReStructuredText
55 lines
1.2 KiB
ReStructuredText
.. SPDX-License-Identifier: GPL-2.0
|
|
|
|
.. _GPIO_GET_LINEINFO_IOCTL:
|
|
|
|
***********************
|
|
GPIO_GET_LINEINFO_IOCTL
|
|
***********************
|
|
|
|
.. warning::
|
|
This ioctl is part of chardev_v1.rst and is obsoleted by
|
|
gpio-v2-get-lineinfo-ioctl.rst.
|
|
|
|
Name
|
|
====
|
|
|
|
GPIO_GET_LINEINFO_IOCTL - Get the publicly available information for a line.
|
|
|
|
Synopsis
|
|
========
|
|
|
|
.. c:macro:: GPIO_GET_LINEINFO_IOCTL
|
|
|
|
``int ioctl(int chip_fd, GPIO_GET_LINEINFO_IOCTL, struct gpioline_info *info)``
|
|
|
|
Arguments
|
|
=========
|
|
|
|
``chip_fd``
|
|
The file descriptor of the GPIO character device returned by `open()`.
|
|
|
|
``info``
|
|
The :c:type:`line_info<gpioline_info>` to be populated, with the
|
|
``offset`` field set to indicate the line to be collected.
|
|
|
|
Description
|
|
===========
|
|
|
|
Get the publicly available information for a line.
|
|
|
|
This information is available independent of whether the line is in use.
|
|
|
|
.. note::
|
|
The line info does not include the line value.
|
|
|
|
The line must be requested using gpio-get-linehandle-ioctl.rst or
|
|
gpio-get-lineevent-ioctl.rst to access its value.
|
|
|
|
Return Value
|
|
============
|
|
|
|
On success 0 and ``info`` is populated with the chip info.
|
|
|
|
On error -1 and the ``errno`` variable is set appropriately.
|
|
Common error codes are described in error-codes.rst.
|