bybrooklyn/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-04-18 06:44:00 -04:00
Code Issues Packages Projects Releases Wiki Activity

drm/simple-kms: Deprecate simple-kms helpers

Browse Source 
Deprecate simple-encoder and simple-display-pipe helpers in favor of
regular atomic helpers. Remove the related documentation. Add TODO
item for converting the remaining drivers.

These helpers have been deprecated for years and many drivers have
been updated to not use them. Still there are a few left and we
occasionally receive new drivers build upon them. Marking them as
deprecated will hopefully resolve these problems. The TODO items
should be easy enough for getting new voluteers started on DRM driver
development.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: David Lechner <david@lechnology.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Link: https://patch.msgid.link/20260319160110.109610-17-tzimmermann@suse.de
This commit is contained in:
Thomas Zimmermann
2026-03-19 16:59:52 +01:00
parent d6cef9bd3d
commit 9886005f89
8 changed files with 39 additions and 341 deletions
Download Patch File Download Diff File Expand all files Collapse all files

12
Documentation/gpu/drm-kms-helpers.rst
View File

@@ -104,18 +104,6 @@ VBLANK Helper Reference
.. kernel-doc:: drivers/gpu/drm/drm_vblank_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
================================

6
Documentation/gpu/introduction.rst
View File

@@ -119,12 +119,6 @@ Simple DRM drivers to use as examples
The DRM subsystem contains a lot of helper functions to ease writing drivers for
simple graphic devices. For example, the `drivers/gpu/drm/tiny/` directory has a
set of drivers that are simple enough to be implemented in a single source file.
These drivers make use of the `struct drm_simple_display_pipe_funcs`, that hides
any complexity of the DRM subsystem and just requires drivers to implement a few
functions needed to operate the device. This could be used for devices that just
need a display pipeline with one full-screen scanout buffer feeding one output.
The tiny DRM drivers are good examples to understand how DRM drivers should look
like. Since are just a few hundreds lines of code, they are quite easy to read.

32
Documentation/gpu/todo.rst
View File

@@ -29,6 +29,38 @@ refactorings already and are an expert in the specific area
Subsystem-wide refactorings
===========================
Open-code drm_simple_encoder_init()
-----------------------------------
The helper drm_simple_encoder_init() was supposed to simplify encoder
initialization. Instead it only added an intermediate layer between atomic
modesetting and the DRM driver.
The task here is to remove drm_simple_encoder_init(). Search for a driver
that calls drm_simple_encoder_init() and inline the helper. The driver will
also need its own instance of drm_encoder_funcs.
Contact: Thomas Zimmermann, respective driver maintainer
Level: Easy
Replace struct drm_simple_display_pipe with regular atomic helpers
------------------------------------------------------------------
The data type struct drm_simple_display_pipe and its helpers were supposed
to simplify driver development. Instead they only added an intermediate layer
between atomic modesetting and the DRM driver.
There are still drivers that use drm_simple_display_pipe. The task here is to
convert them to use regular atomic helpers. Search for a driver that calls
drm_simple_display_pipe_init() and inline all helpers from drm_simple_kms_helper.c
into the driver, such that no simple-KMS interfaces are required. Please also
rename all inlined fucntions according to driver conventions.
Contact: Thomas Zimmermann, respective driver maintainer
Level: Easy
Remove custom dumb_map_offset implementations
---------------------------------------------