From 32a0a0da530eab78d755474270bf53274b93a1e6 Mon Sep 17 00:00:00 2001 From: Kent Gibson Date: Mon, 15 Jan 2024 08:48:39 +0800 Subject: Documentation: gpio: add chardev userspace API documentation Add documentation for the GPIO character device userspace API. Added to the userspace-api book, but also provide a link from the admin-guide book, as historically the GPIO documentation has been there. Signed-off-by: Kent Gibson Reviewed-by: Linus Walleij Signed-off-by: Bartosz Golaszewski --- .../userspace-api/gpio/gpio-get-chipinfo-ioctl.rst | 41 ++++++++++++++++++++++ 1 file changed, 41 insertions(+) create mode 100644 Documentation/userspace-api/gpio/gpio-get-chipinfo-ioctl.rst (limited to 'Documentation/userspace-api/gpio/gpio-get-chipinfo-ioctl.rst') diff --git a/Documentation/userspace-api/gpio/gpio-get-chipinfo-ioctl.rst b/Documentation/userspace-api/gpio/gpio-get-chipinfo-ioctl.rst new file mode 100644 index 000000000000..05f07fdefe2f --- /dev/null +++ b/Documentation/userspace-api/gpio/gpio-get-chipinfo-ioctl.rst @@ -0,0 +1,41 @@ +.. SPDX-License-Identifier: GPL-2.0 + +.. _GPIO_GET_CHIPINFO_IOCTL: + +*********************** +GPIO_GET_CHIPINFO_IOCTL +*********************** + +Name +==== + +GPIO_GET_CHIPINFO_IOCTL - Get the publicly available information for a chip. + +Synopsis +======== + +.. c:macro:: GPIO_GET_CHIPINFO_IOCTL + +``int ioctl(int chip_fd, GPIO_GET_CHIPINFO_IOCTL, struct gpiochip_info *info)`` + +Arguments +========= + +``chip_fd`` + The file descriptor of the GPIO character device returned by `open()`. + +``info`` + The :c:type:`chip_info` to be populated. + +Description +=========== + +Gets the publicly available information for a particular GPIO chip. + +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. -- cgit v1.2.3