Documentation/userspace-api/gpio/error-codes.rst
Source file repositories/reference/linux-study-clean/Documentation/userspace-api/gpio/error-codes.rst
File Facts
- System
- Linux kernel
- Corpus path
Documentation/userspace-api/gpio/error-codes.rst- Extension
.rst- Size
- 2309 bytes
- Lines
- 80
- Domain
- Support Tooling And Documentation
- Bucket
- Documentation
- Inferred role
- Support Tooling And Documentation: documentation
- Status
- atlas-only
Why This File Exists
Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
- Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
Dependency Surface
- No C-style include directives detected by the generator.
Detected Declarations
- No top-level syscall, struct, function, initcall, or export declaration detected by the generator.
Annotated Snippet
.. SPDX-License-Identifier: GPL-2.0
.. _gpio_errors:
*******************
GPIO Error Codes
*******************
.. _gpio-errors:
.. tabularcolumns:: |p{2.5cm}|p{15.0cm}|
.. flat-table:: Common GPIO error codes
:header-rows: 0
:stub-columns: 0
:widths: 1 16
- - ``EAGAIN`` (aka ``EWOULDBLOCK``)
- The device was opened in non-blocking mode and a read can't
be performed as there is no data available.
- - ``EBADF``
- The file descriptor is not valid.
- - ``EBUSY``
- The ioctl can't be handled because the device is busy. Typically
returned when an ioctl attempts something that would require the
usage of a resource that was already allocated. The ioctl must not
be retried without performing another action to fix the problem
first.
- - ``EFAULT``
- There was a failure while copying data from/to userspace, probably
caused by an invalid pointer reference.
- - ``EINVAL``
- One or more of the ioctl parameters are invalid or out of the
allowed range. This is a widely used error code.
- - ``ENODEV``
- Device not found or was removed.
- - ``ENOMEM``
- There's not enough memory to handle the desired operation.
- - ``EPERM``
- Permission denied. Typically returned in response to an attempt
to perform an action incompatible with the current line
configuration.
- - ``EIO``
- I/O error. Typically returned when there are problems communicating
with a hardware device or requesting features that hardware does not
support. This could indicate broken or flaky hardware.
It's a 'Something is wrong, I give up!' type of error.
- - ``ENXIO``
- Typically returned when a feature requiring interrupt support was
requested, but the line does not support interrupts.
Annotation
- Atlas domain: Support Tooling And Documentation / Documentation.
- Implementation status: atlas-only.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.