Documentation/userspace-api/media/dvb/legacy_dvb_osd.rst

Source file repositories/reference/linux-study-clean/Documentation/userspace-api/media/dvb/legacy_dvb_osd.rst

File Facts

System: Linux kernel
Corpus path: Documentation/userspace-api/media/dvb/legacy_dvb_osd.rst
Extension: .rst
Size: 14193 bytes
Lines: 884
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.
Touches IRQ or DMA behavior; this matters for the representative real-device path.
Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

fcntl.h

Detected Declarations

No top-level syscall, struct, function, initcall, or export declaration detected by the generator.

Annotated Snippet

.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later OR GPL-2.0

.. c:namespace:: dtv.legacy.osd

.. _dvb_osd:

==============
DVB OSD Device
==============

.. attention:: Do **not** use in new drivers!
             See: :ref:`legacy_dvb_decoder_notes`

The DVB OSD device controls the OnScreen-Display of the AV7110 based
DVB-cards with hardware MPEG2 decoder. It can be accessed through
``/dev/dvb/adapter?/osd0``.
Data types and ioctl definitions can be accessed by including
``linux/dvb/osd.h`` in your application.

The OSD is not a frame-buffer like on many other cards.
It is a kind of canvas one can draw on.
The color-depth is limited depending on the memory size installed.
An appropriate palette of colors has to be set up.
The installed memory size can be identified with the `OSD_GET_CAPABILITY`_
ioctl.

OSD Data Types
==============

OSD_Command
-----------

Synopsis
~~~~~~~~

.. code-block:: c

    typedef enum {
	/* All functions return -2 on "not open" */
	OSD_Close = 1,
	OSD_Open,
	OSD_Show,
	OSD_Hide,
	OSD_Clear,
	OSD_Fill,
	OSD_SetColor,
	OSD_SetPalette,
	OSD_SetTrans,
	OSD_SetPixel,
	OSD_GetPixel,
	OSD_SetRow,
	OSD_SetBlock,
	OSD_FillRow,
	OSD_FillBlock,
	OSD_Line,
	OSD_Query,
	OSD_Test,
	OSD_Text,
	OSD_SetWindow,
	OSD_MoveWindow,
	OSD_OpenRaw,
    } OSD_Command;

Commands
~~~~~~~~

.. note::  All functions return -2 on "not open"

.. flat-table::
    :header-rows:  1

Annotation

Immediate include surface: `fcntl.h`.
Atlas domain: Support Tooling And Documentation / Documentation.
Implementation status: atlas-only.
IRQ or DMA behavior appears here, which is relevant to the selected PCIe/NVMe device path.

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.