Documentation/input/gameport-programming.rst

Source file repositories/reference/linux-study-clean/Documentation/input/gameport-programming.rst

File Facts

System: Linux kernel
Corpus path: Documentation/input/gameport-programming.rst
Extension: .rst
Size: 6489 bytes
Lines: 234
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.
Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

No C-style include directives detected by the generator.

Detected Declarations

struct gameport
function my_trigger
function my_read
function my_cooked_read
function my_open

Annotated Snippet

struct gameport {

	void *port_data;

A private pointer for free use in the gameport driver. (Not the joystick
driver!)

::

	char name[32];

Driver's name as set by driver calling gameport_set_name(). Informational
purpose only.

::

	char phys[32];

gameport's physical name/description as set by driver calling gameport_set_phys().
Informational purpose only.

::

	int io;

I/O address for use with raw mode. You have to either set this, or ->read()
to some value if your gameport supports raw mode.

::

	int speed;

Raw mode speed of the gameport reads in thousands of reads per second.

::

	int fuzz;

If the gameport supports cooked mode, this should be set to a value that
represents the amount of noise in the data. See
:ref:`gameport_pgm_cooked_mode`.

::

	void (*trigger)(struct gameport *);

Trigger. This function should trigger the ns558 oneshots. If set to NULL,
outb(0xff, io) will be used.

::

	unsigned char (*read)(struct gameport *);

Read the buttons and ns558 oneshot bits. If set to NULL, inb(io) will be
used instead.

::

	int (*cooked_read)(struct gameport *, int *axes, int *buttons);

If the gameport supports cooked mode, it should point this to its cooked
read function. It should fill axes[0..3] with four values of the joystick axes
and buttons[0] with four bits representing the buttons.

::

	int (*calibrate)(struct gameport *, int *axes, int *max);

Function for calibrating the ADC hardware. When called, axes[0..3] should be
pre-filled by cooked data by the caller, max[0..3] should be pre-filled with

Annotation

Detected declarations: `struct gameport`, `function my_trigger`, `function my_read`, `function my_cooked_read`, `function my_open`.
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.