=============================
Mode Setting Helper Functions
=============================
The DRM subsystem aims for a strong separation between core code and helper
libraries. Core code takes care of general setup and teardown and decoding
userspace requests to kernel internal objects. Everything else is handled by a
large set of helper libraries, which can be combined freely to pick and choose
for each driver what fits, and avoid shared code where special behaviour is
needed.
This distinction between core code and helpers is especially strong in the
modesetting code, where there's a shared userspace ABI for all drivers. This is
in contrast to the render side, where pretty much everything (with very few
exceptions) can be considered optional helper code.
There are a few areas these helpers can grouped into:
* Helpers to implement modesetting. The important ones here are the atomic
helpers. Old drivers still often use the legacy CRTC helpers. They both share
the same set of common helper vtables. For really simple drivers (anything
that would have been a great fit in the deprecated fbdev subsystem) there's
also the simple display pipe helpers.
* There's a big pile of helpers for handling outputs. First the generic bridge
helpers for handling encoder and transcoder IP blocks. Second the panel helpers
for handling panel-related information and logic. Plus then a big set of
helpers for the various sink standards (DisplayPort, HDMI, MIPI DSI). Finally
there's also generic helpers for handling output probing, and for dealing with
EDIDs.
* The last group of helpers concerns itself with the frontend side of a display
pipeline: Planes, handling rectangles for visibility checking and scissoring,
flip queues and assorted bits.
Modeset Helper Reference for Common Vtables
===========================================
.. kernel-doc:: include/drm/drm_modeset_helper_vtables.h
:doc: overview
.. kernel-doc:: include/drm/drm_modeset_helper_vtables.h
:internal:
.. _drm_atomic_helper:
Atomic Modeset Helper Functions Reference
=========================================
Overview
--------
.. kernel-doc:: drivers/gpu/drm/drm_atomic_helper.c
:doc: overview
Implementing Asynchronous Atomic Commit
---------------------------------------
.. kernel-doc:: drivers/gpu/drm/drm_atomic_helper.c
:doc: implementing nonblocking commit
Helper Functions Reference
--------------------------
.. kernel-doc:: include/drm/drm_atomic_helper.h
:internal:
.. kernel-doc:: drivers/gpu/drm/drm_atomic_helper.c
:export:
Atomic State Reset and Initialization
-------------------------------------
.. kernel-doc:: drivers/gpu/drm/drm_atomic_state_helper.c
:doc: atomic state reset and initialization
Atomic State Helper Reference
-----------------------------
.. kernel-doc:: drivers/gpu/drm/drm_atomic_state_helper.c
:export:
GEM Atomic Helper Reference
---------------------------
.. kernel-doc:: drivers/gpu/drm/drm_gem_atomic_helper.c
:doc: overview
.. kernel-doc:: include/drm/drm_gem_atomic_helper.h
:internal:
.. kernel-doc:: drivers/gpu/drm/drm_gem_atomic_helper.c
:export:
Simple KMS Helper Reference
===========================
.. kernel-doc:: drivers/gpu/drm/drm_simple_kms_helper.c
:doc: overview
.. kernel-doc:: include/drm/drm_simple_kms_helper.h
:internal:
.. kernel-doc:: drivers/gpu/drm/drm_simple_kms_helper.c
:export:
fbdev Helper Functions Reference
================================
.. kernel-doc:: drivers/gpu/drm/drm_fb_helper.c
:doc: fbdev helpers
.. kernel-doc:: drivers/gpu/drm/drm_fbdev_dma.c
:export:
.. kernel-doc:: drivers/gpu/drm/drm_fbdev_shmem.c
:export:
.. kernel-doc:: drivers/gpu/drm/drm_fbdev_ttm.c
:export:
.. kernel-doc:: include/drm/drm_fb_helper.h
:internal:
.. kernel-doc:: drivers/gpu/drm/drm_fb_helper.c
:export:
format Helper Functions Reference
=================================
.. kernel-doc:: drivers/gpu/drm/drm_format_helper.c
:export:
Framebuffer DMA Helper Functions Reference
==========================================
.. kernel-doc:: drivers/gpu/drm/drm_fb_dma_helper.c
:doc: framebuffer dma helper functions
.. kernel-doc:: drivers/gpu/drm/drm_fb_dma_helper.c
:export:
Framebuffer GEM Helper Reference
================================
.. kernel-doc:: drivers/gpu/drm/drm_gem_framebuffer_helper.c
:doc: overview
.. kernel-doc:: drivers/gpu/drm/drm_gem_framebuffer_helper.c
:export:
.. _drm_bridges:
Bridges
=======
Overview
--------
.. kernel-doc:: drivers/gpu/drm/drm_bridge.c
:doc: overview
Display Driver Integration
--------------------------
.. kernel-doc:: drivers/gpu/drm/drm_bridge.c
:doc: display driver integration
Special Care with MIPI-DSI bridges
----------------------------------
.. kernel-doc:: drivers/gpu/drm/drm_bridge.c
:doc: special care dsi
Bridge Operations
-----------------
.. kernel-doc:: drivers/gpu/drm/drm_bridge.c
:doc: bridge operations
Bridge Connector Helper
-----------------------
.. kernel-doc:: drivers/gpu/drm/display/drm_bridge_connector.c
:doc: overview
Bridge Helper Reference
-------------------------
.. kernel-doc:: include/drm/drm_bridge.h
:internal:
.. kernel-doc:: drivers/gpu/drm/drm_bridge.c
:export:
MIPI-DSI bridge operation
-------------------------
.. kernel-doc:: drivers/gpu/drm/drm_bridge.c
:doc: dsi bridge operations
Bridge Connector Helper Reference
---------------------------------
.. kernel-doc:: drivers/gpu/drm/display/drm_bridge_connector.c
:export:
Panel-Bridge Helper Reference
-----------------------------
.. kernel-doc:: drivers/gpu/drm/bridge/panel.c
:export:
.. _drm_panel_helper:
Panel Helper Reference
======================
.. kernel-doc:: drivers/gpu/drm/drm_panel.c
:doc: drm panel
.. kernel-doc:: include/drm/drm_panel.h
:internal:
.. kernel-doc:: drivers/gpu/drm/drm_panel.c
:export:
.. kernel-doc:: drivers/gpu/drm/drm_panel_orientation_quirks.c
:export:
Panel Self Refresh Helper Reference
===================================
.. kernel-doc:: drivers/gpu/drm/drm_self_refresh_helper.c
:doc: overview
.. kernel-doc:: drivers/gpu/drm/drm_self_refresh_helper.c
:export:
HDCP Helper Functions Reference
===============================
.. kernel-doc:: drivers/gpu/drm/display/drm_hdcp_helper.c
:export:
Display Port Helper Functions Reference
=======================================
.. kernel-doc:: drivers/gpu/drm/display/drm_dp_helper.c
:doc: dp helpers
.. kernel-doc:: include/drm/display/drm_dp.h
:internal:
.. kernel-doc:: include/drm/display/drm_dp_helper.h
:internal:
.. kernel-doc:: drivers/gpu/drm/display/drm_dp_helper.c
:export:
Display Port CEC Helper Functions Reference
===========================================
.. kernel-doc:: drivers/gpu/drm/display/drm_dp_cec.c
:doc: dp cec helpers
.. kernel-doc:: drivers/gpu/drm/display/drm_dp_cec.c
:export:
Display Port Dual Mode Adaptor Helper Functions Reference
=========================================================
.. kernel-doc:: drivers/gpu/drm/display/drm_dp_dual_mode_helper.c
:doc: dp dual mode helpers
.. kernel-doc:: include/drm/display/drm_dp_dual_mode_helper.h
:internal:
.. kernel-doc:: drivers/gpu/drm/display/drm_dp_dual_mode_helper.c
:export:
Display Port MST Helpers
========================
Overview
--------
.. kernel-doc:: drivers/gpu/drm/display/drm_dp_mst_topology.c
:doc: dp mst helper
.. kernel-doc:: drivers/gpu/drm/display/drm_dp_mst_topology.c
:doc: Branch device and port refcounting
Functions Reference
-------------------
.. kernel-doc:: include/drm/display/drm_dp_mst_helper.h
:internal:
.. kernel-doc:: drivers/gpu/drm/display/drm_dp_mst_topology.c
:export:
Topology Lifetime Internals
---------------------------
These functions aren't exported to drivers, but are documented here to help make
the MST topology helpers easier to understand
.. kernel-doc:: drivers/gpu/drm/display/drm_dp_mst_topology.c
:functions: drm_dp_mst_topology_try_get_mstb drm_dp_mst_topology_get_mstb
drm_dp_mst_topology_put_mstb
drm_dp_mst_topology_try_get_port drm_dp_mst_topology_get_port
drm_dp_mst_topology_put_port
drm_dp_mst_get_mstb_malloc drm_dp_mst_put_mstb_malloc
MIPI DBI Helper Functions Reference
===================================
.. kernel-doc:: drivers/gpu/drm/drm_mipi_dbi.c
:doc: overview
.. kernel-doc:: include/drm/drm_mipi_dbi.h
:internal:
.. kernel-doc:: drivers/gpu/drm/drm_mipi_dbi.c
:export:
MIPI DSI Helper Functions Reference
===================================
.. kernel-doc:: drivers/gpu/drm/drm_mipi_dsi.c
:doc: dsi helpers
.. kernel-doc:: include/drm/drm_mipi_dsi.h
:internal:
.. kernel-doc:: drivers/gpu/drm/drm_mipi_dsi.c
:export:
Display Stream Compression Helper Functions Reference
=====================================================
.. kernel-doc:: drivers/gpu/drm/display/drm_dsc_helper.c
:doc: dsc helpers
.. kernel-doc:: include/drm/display/drm_dsc.h
:internal:
.. kernel-doc:: drivers/gpu/drm/display/drm_dsc_helper.c
:export:
Output Probing Helper Functions Reference
=========================================
.. kernel-doc:: drivers/gpu/drm/drm_probe_helper.c
:doc: output probing helper overview
.. kernel-doc:: drivers/gpu/drm/drm_probe_helper.c
:export:
EDID Helper Functions Reference
===============================
.. kernel-doc:: include/drm/drm_edid.h
:internal:
.. kernel-doc:: drivers/gpu/drm/drm_edid.c
:export:
.. kernel-doc:: include/drm/drm_eld.h
:internal:
.. kernel-doc:: drivers/gpu/drm/drm_eld.c
:export:
SCDC Helper Functions Reference
===============================
.. kernel-doc:: drivers/gpu/drm/display/drm_scdc_helper.c
:doc: scdc helpers
.. kernel-doc:: include/drm/display/drm_scdc_helper.h
:internal:
.. kernel-doc:: drivers/gpu/drm/display/drm_scdc_helper.c
:export:
HDMI Infoframes Helper Reference
================================
Strictly speaking this is not a DRM helper library but generally usable
by any driver interfacing with HDMI outputs like v4l or alsa drivers.
But it nicely fits into the overall topic of mode setting helper
libraries and hence is also included here.
.. kernel-doc:: include/linux/hdmi.h
:internal:
.. kernel-doc:: drivers/video/hdmi.c
:export:
Rectangle Utilities Reference
=============================
.. kernel-doc:: include/drm/drm_rect.h
:doc: rect utils
.. kernel-doc:: include/drm/drm_rect.h
:internal:
.. kernel-doc:: drivers/gpu/drm/drm_rect.c
:export:
Flip-work Helper Reference
==========================
.. kernel-doc:: include/drm/drm_flip_work.h
:doc: flip utils
.. kernel-doc:: include/drm/drm_flip_work.h
:internal:
.. kernel-doc:: drivers/gpu/drm/drm_flip_work.c
:export:
Auxiliary Modeset Helpers
=========================
.. kernel-doc:: drivers/gpu/drm/drm_modeset_helper.c
:doc: aux kms helpers
.. kernel-doc:: drivers/gpu/drm/drm_modeset_helper.c
:export:
OF/DT Helpers
=============
.. kernel-doc:: drivers/gpu/drm/drm_of.c
:doc: overview
.. kernel-doc:: drivers/gpu/drm/drm_of.c
:export:
Legacy Plane Helper Reference
=============================
.. kernel-doc:: drivers/gpu/drm/drm_plane_helper.c
:doc: overview
.. kernel-doc:: drivers/gpu/drm/drm_plane_helper.c
:export:
Legacy CRTC/Modeset Helper Functions Reference
==============================================
.. kernel-doc:: drivers/gpu/drm/drm_crtc_helper.c
:doc: overview
.. kernel-doc:: drivers/gpu/drm/drm_crtc_helper.c
:export:
Privacy-screen class
====================
.. kernel-doc:: drivers/gpu/drm/drm_privacy_screen.c
:doc: overview
.. kernel-doc:: include/drm/drm_privacy_screen_driver.h
:internal:
.. kernel-doc:: include/drm/drm_privacy_screen_machine.h
:internal:
.. kernel-doc:: drivers/gpu/drm/drm_privacy_screen.c
:export:
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