drm/Documentation: Refine TODO for backlight helpers in tinydrm

Add a summary which resulted from discussions on what should
be done to refactor backlight helpers in tinydrm so that
they can be used in other drivers as well.

Signed-off-by: Meghana Madhyastha <meghana.madhyastha@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20170927105116.GA30391@meghana-HP-Pavilion-Notebook
This commit is contained in:
Meghana Madhyastha 2017-09-27 16:21:23 +05:30 committed by Daniel Vetter
parent ffeeeed0ae
commit 9949b355dc

View File

@ -351,7 +351,16 @@ those drivers as simple as possible, so lots of room for refactoring:
- backlight helpers, probably best to put them into a new drm_backlight.c.
This is because drivers/video is de-facto unmaintained. We could also
move drivers/video/backlight to drivers/gpu/backlight and take it all
over within drm-misc, but that's more work.
over within drm-misc, but that's more work. Backlight helpers require a fair
bit of reworking and refactoring. A simple example is the enabling of a backlight.
Tinydrm has helpers for this. It would be good if other drivers can also use the
helper. However, there are various cases we need to consider i.e different
drivers seem to have different ways of enabling/disabling a backlight.
We also need to consider the backlight drivers (like gpio_backlight). The situation
is further complicated by the fact that the backlight is tied to fbdev
via fb_notifier_callback() which has complicated logic. For further details, refer
to the following discussion thread:
https://groups.google.com/forum/#!topic/outreachy-kernel/8rBe30lwtdA
- spi helpers, probably best put into spi core/helper code. Thierry said
the spi maintainer is fast&reactive, so shouldn't be a big issue.