An HLCDC layers in Atmel's nomenclature is either a DRM plane or a 'Post
Processing Layer' which can be used to output the results of the HLCDC
composition in a memory buffer.
atmel_hlcdc_layer.c was designed to be generic enough to be re-usable in
both cases, but we're not exposing the post-processing layer yet, and
even if we were, I'm not sure the code would provide the necessary tools
to manipulate this kind of layer.
Moreover, the code in atmel_hlcdc_{plane,layer}.c was designed before the
atomic modesetting API, and was trying solve the
check-setting/commit-if-ok/rollback-otherwise problem, which is now
entirely solved by the existing core infrastructure.
And finally, the code in atmel_hlcdc_layer.c is over-complicated compared
to what we really need. This rework is a good excuse to simplify it. Note
that this rework solves an existing resource leak (leading to a -EBUSY
error) which I failed to clearly identify.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Eric Anholt <eric@anholt.net>
Tested-by: Nicolas Ferre <nicolas.ferre@microchip.com>
The Atmel HLCDC (HLCD Controller) IP available on some Atmel SoCs (i.e.
at91sam9n12, at91sam9x5 family or sama5d3 family) provides a display
controller device.
This display controller supports at least one primary plane and might
provide several overlays and an hardware cursor depending on the IP
version.
At the moment, this driver only implements an RGB connector to interface
with LCD panels, but support for other kind of external devices might be
added later.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Tested-by: Anthony Harivel <anthony.harivel@emtrion.de>
Tested-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>