linux-arm-kernel.lists.infradead.org archive mirror
 help / color / mirror / Atom feed
From: maxime.ripard@free-electrons.com (Maxime Ripard)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH 06/19] drm/blend: Add a generic alpha property
Date: Tue, 9 Jan 2018 14:53:22 +0100	[thread overview]
Message-ID: <20180109135322.7lb3snbxfcezobhz@flea> (raw)
In-Reply-To: <20180109123241.GU26573@phenom.ffwll.local>

On Tue, Jan 09, 2018 at 01:32:41PM +0100, Daniel Vetter wrote:
> On Tue, Jan 09, 2018 at 11:56:25AM +0100, Maxime Ripard wrote:
> > Some drivers duplicate the logic to create a property to store a per-plane
> > alpha.
> > 
> > Let's create a helper in order to move that to the core.
> > 
> > Cc: Boris Brezillon <boris.brezillon@free-electrons.com>
> > Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> > Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
> 
> Do we have userspace for this?

Wayland seems to be on its way to implement this, with ChromeOS using
it:
https://lists.freedesktop.org/archives/wayland-devel/2017-August/034741.html

and more specifically:
https://chromium.googlesource.com/chromium/src/+/master/third_party/wayland-protocols/unstable/alpha-compositing/alpha-compositing-unstable-v1.xml#118

> Is encoding a fixed 0-255 range really the best idea?

I don't really know, is there hardware or formats where there is more
than 255? Or did you mean less than that?

> I know other drivers have skimped on the rules here a bit ... But at least
> internally (i.e. within the drm_plane_state) we probably should restrict
> ourselves to u8. And this needs real docs (i.e. the full blend equation
> drivers are supposed to implement).

You mean straight vs premultiplied? Maybe we should implement this as
an additional property in read only depending on how the hardware
behaves?

Thanks!
Maxime

-- 
Maxime Ripard, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 833 bytes
Desc: not available
URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20180109/a0708274/attachment.sig>

  reply	other threads:[~2018-01-09 13:53 UTC|newest]

Thread overview: 42+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-01-09 10:56 [PATCH 00/19] drm/sun4i: Support more planes, zpos and plane-wide alpha Maxime Ripard
2018-01-09 10:56 ` [PATCH 01/19] drm/fourcc: Add a function to tell if the format embeds alpha Maxime Ripard
2018-01-09 12:26   ` Boris Brezillon
2018-01-09 12:29   ` Laurent Pinchart
2018-01-09 13:28     ` Maxime Ripard
2018-01-15 15:47       ` Ayan Halder
2018-01-09 10:56 ` [PATCH 02/19] drm/atmel-hlcdc: Use the alpha format helper Maxime Ripard
2018-01-09 12:27   ` Boris Brezillon
2018-01-09 10:56 ` [PATCH 03/19] drm/exynos: " Maxime Ripard
2018-01-12  1:20   ` Inki Dae
2018-01-09 10:56 ` [PATCH 04/19] drm/rockchip: " Maxime Ripard
2018-01-16  0:42   ` Sandy Huang
2018-01-09 10:56 ` [PATCH 05/19] drm/vc4: " Maxime Ripard
2018-01-09 12:34   ` Daniel Vetter
2018-01-09 17:34   ` Eric Anholt
2018-01-09 10:56 ` [PATCH 06/19] drm/blend: Add a generic alpha property Maxime Ripard
2018-01-09 12:31   ` Boris Brezillon
2018-01-09 12:32   ` Daniel Vetter
2018-01-09 13:53     ` Maxime Ripard [this message]
2018-01-09 14:28       ` Daniel Vetter
2018-01-11 15:58         ` Maxime Ripard
2018-01-11 16:36           ` Daniel Vetter
2018-01-11 18:34             ` Laurent Pinchart
2018-01-17  9:20               ` Maxime Ripard
2018-01-17  9:30                 ` Daniel Vetter
2018-01-09 12:34   ` Laurent Pinchart
2018-01-09 13:59     ` Maxime Ripard
2018-01-09 10:56 ` [PATCH 07/19] drm/atmel-hclcdc: Convert to the new " Maxime Ripard
2018-01-09 12:31   ` Boris Brezillon
2018-01-09 10:56 ` [PATCH 08/19] drm/rcar-du: " Maxime Ripard
2018-01-09 12:37   ` Laurent Pinchart
2018-01-09 10:56 ` [PATCH 09/19] drm/sun4i: backend: Fix structure indentation Maxime Ripard
2018-01-09 10:56 ` [PATCH 10/19] drm/sun4i: backend: Fix define typo Maxime Ripard
2018-01-09 10:56 ` [PATCH 11/19] drm/sun4i: framebuffer: Add a custom atomic_check Maxime Ripard
2018-01-09 10:56 ` [PATCH 12/19] drm/sun4i: backend: Move the coord function in the shared part Maxime Ripard
2018-01-09 10:56 ` [PATCH 13/19] drm/sun4i: backend: Set a default zpos in our reset hook Maxime Ripard
2018-01-09 10:56 ` [PATCH 14/19] drm/sun4i: backend: Add support for zpos Maxime Ripard
2018-01-09 10:56 ` [PATCH 15/19] drm/sun4i: backend: Check for the number of alpha planes Maxime Ripard
2018-01-09 10:56 ` [PATCH 16/19] drm/sun4i: backend: Assign the pipes automatically Maxime Ripard
2018-01-09 10:56 ` [PATCH 17/19] drm/sun4i: backend: Make zpos configurable Maxime Ripard
2018-01-09 10:56 ` [PATCH 18/19] drm/sun4i: Add support for plane alpha Maxime Ripard
2018-01-09 10:56 ` [PATCH 19/19] drm/sun4i: backend: Remove ARGB spoofing Maxime Ripard

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20180109135322.7lb3snbxfcezobhz@flea \
    --to=maxime.ripard@free-electrons.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).