From: Raphael Gallais-Pou <raphael.gallais-pou@foss.st.com>
To: Yannick Fertre <yannick.fertre@foss.st.com>,
Philippe Cornu <philippe.cornu@foss.st.com>,
Benjamin Gaignard <benjamin.gaignard@linaro.org>
Cc: David Airlie <airlied@linux.ie>, Daniel Vetter <daniel@ffwll.ch>,
"Maxime Coquelin" <mcoquelin.stm32@gmail.com>,
Alexandre Torgue <alexandre.torgue@foss.st.com>,
<dri-devel@lists.freedesktop.org>,
<linux-stm32@st-md-mailman.stormreply.com>,
<linux-arm-kernel@lists.infradead.org>,
<linux-kernel@vger.kernel.org>,
Raphael Gallais-Pou <raphael.gallais-pou@foss.st.com>,
Raphael Gallais-Pou <raphael.gallais-pou@st.com>
Subject: [PATCH v2] drm/stm: ltdc: add layer alpha support
Date: Tue, 7 Sep 2021 17:15:34 +0200 [thread overview]
Message-ID: <20210907151534.6013-1-raphael.gallais-pou@foss.st.com> (raw)
Android Hardware Composer supports alpha values applied to layers.
Enabling non-opaque layers for the STM CRTC could help offload GPU
resources for screen composition.
Signed-off-by: Raphael Gallais-Pou <raphael.gallais-pou@foss.st.com>
Acked-by: Yannick Fertre <yannick.fertre@foss.st.com>
Reviewed-by: Yannick Fertre <yannick.fertre@foss.st.com>
---
drivers/gpu/drm/stm/ltdc.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/stm/ltdc.c b/drivers/gpu/drm/stm/ltdc.c
index 195de30eb90c..e0fef8bacfa8 100644
--- a/drivers/gpu/drm/stm/ltdc.c
+++ b/drivers/gpu/drm/stm/ltdc.c
@@ -845,7 +845,7 @@ static void ltdc_plane_atomic_update(struct drm_plane *plane,
LXCFBLR_CFBLL | LXCFBLR_CFBP, val);
/* Specifies the constant alpha value */
- val = CONSTA_MAX;
+ val = newstate->alpha >> 8;
reg_update_bits(ldev->regs, LTDC_L1CACR + lofs, LXCACR_CONSTA, val);
/* Specifies the blending factors */
@@ -997,6 +997,8 @@ static struct drm_plane *ltdc_plane_create(struct drm_device *ddev,
drm_plane_helper_add(plane, <dc_plane_helper_funcs);
+ drm_plane_create_alpha_property(plane);
+
DRM_DEBUG_DRIVER("plane:%d created\n", plane->base.id);
return plane;
--
2.17.1
next reply other threads:[~2021-09-07 15:17 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-07 15:15 Raphael Gallais-Pou [this message]
2021-09-09 13:08 ` [PATCH v2] drm/stm: ltdc: add layer alpha support Philippe CORNU
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=20210907151534.6013-1-raphael.gallais-pou@foss.st.com \
--to=raphael.gallais-pou@foss.st.com \
--cc=airlied@linux.ie \
--cc=alexandre.torgue@foss.st.com \
--cc=benjamin.gaignard@linaro.org \
--cc=daniel@ffwll.ch \
--cc=dri-devel@lists.freedesktop.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-stm32@st-md-mailman.stormreply.com \
--cc=mcoquelin.stm32@gmail.com \
--cc=philippe.cornu@foss.st.com \
--cc=raphael.gallais-pou@st.com \
--cc=yannick.fertre@foss.st.com \
/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).