From: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
To: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
Cc: Sam Ravnborg <sam@ravnborg.org>,
Simon Horman <horms@verge.net.au>,
Magnus Damm <magnus.damm@gmail.com>,
Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>,
"dri-devel@lists.freedesktop.org"
<dri-devel@lists.freedesktop.org>,
"devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"linux-renesas-soc@vger.kernel.org"
<linux-renesas-soc@vger.kernel.org>,
Chris Paterson <Chris.Paterson2@renesas.com>,
Biju Das <biju.das@bp.renesas.com>,
Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
Jacopo Mondi <jacopo+renesas@jmondi.org>,
"ebiharaml@si-linux.co.jp" <ebiharaml@si-linux.co.jp>,
Fabrizio Castro <fabrizio.castro@bp.renesas.com>,
Geert Uytterhoeven <geert+renesas@glider.be>,
David Airlie <airlied@linux.ie>, Daniel Vetter <daniel@ffwll.ch>,
Rob Herring <robh+dt@kernel.org>,
Mark Rutland <mark.rutland@arm.com>,
Thierry Reding <thierry.reding@gmail.com>,
Maxime Ripard <maxime.ripard@bootlin.com>,
Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
Sean Paul <sean@poorly.run>, Andrzej Hajda <a.hajda@samsung.com>
Subject: RE: [PATCH v3 0/8] Add dual-LVDS panel support to EK874
Date: Tue, 22 Oct 2019 16:30:07 +0000 [thread overview]
Message-ID: <TYXPR01MB17753318ECA1556FE53C262AC0680@TYXPR01MB1775.jpnprd01.prod.outlook.com> (raw)
In-Reply-To: <1567017402-5895-1-git-send-email-fabrizio.castro@bp.renesas.com>
Hi Laurent,
Did you have any time to look into this series?
Thanks,
Fab
> From: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
> Sent: 28 August 2019 19:37
> Subject: [PATCH v3 0/8] Add dual-LVDS panel support to EK874
>
> Dear All,
>
> this series adds support for dual-LVDS panel IDK-2121WR
> from Advantech:
> https://buy.advantech.eu/Displays/Embedded-LCD-Kits-High-Brightness/model-IDK-2121WR-K2FHA2E.htm
>
> V3 approaches the problem in a completely different way, we now
> have two new properties to mark the ports in the DT as receiving
> even pixels and odd pixels: dual-lvds-even-pixels and dual-lvds-odd-pixels,
> which means device drivers should not use bridge specific or panel
> specific dual_link flags. Also, in this case the DT describes the
> connection fully.
>
> In order for the solution to be generic, I have exported a new helper
> (drm_of_lvds_get_dual_link_configuration) to walk the device tree,
> and figure out if the connection is dual-LVDS. The same helper gives
> information about the configuration of the connection. If Px is connected
> to a port expecting even pixels and Py is connected to a port expecting
> odd pixels, then the helper returns DRM_LVDS_DUAL_LINK_EVEN_ODD_PIXELS
> (like in the example below), otherwise it returns
> DRM_LVDS_DUAL_LINK_ODD_EVEN_PIXELS.
>
>
> -------- dual-lvds-even-pixels --------
> | |---- ----| |
> | | Px |---------------------->| Pn | |
> | |---- ----| |
> | SOURCE | dual-lvds-odd-pixels | SINK |
> | |---- ----| |
> | | Py |---------------------->| Pm | |
> | |---- ----| |
> -------- --------
>
> The device driver for the encoder then will work out if with the current
> wiring the pixels need swapping or not.
>
> The same solution works for both panels and bridges.
>
> Since the DT describes the connection fully, driver
> drivers/gpu/drm/panel/panel-lvds.c works out-of-the-box, no changes
> required, however, this implementation opens up a problem with the
> dt-bindings.
> Driver drivers/gpu/drm/panel/panel-lvds.c can still be pleased by
> a port node, but also by a ports node.
> I have created Documentation/devicetree/bindings/display/bus-timings/lvds.yaml
> with the idea of including it from panels and bridges dt-bindings
> supporting dual-LVDS (and of course the dt-bindings for the specific
> devices should say which port should be marked as what), but file
> Documentation/devicetree/bindings/display/panel/lvds.yaml formally
> requires property "port", while with this implementation it should require
> OneOf "port" and "ports", and unfortunately I can't seem to find a neat way
> aroud that, other than creating a new compatible string
> (e.g. "panel-dual-lvds"), a new dt-binding document for it, and of course adding
> support for the new compatible string to drivers/gpu/drm/panel/panel-lvds.c.
> As a result, this series is missing (at least) a patch necessary to fully
> document the new implementation within
> Documentation/devicetree/bindings/display/panel/lvds.yaml
>
> Rob, do you have any suggestions? Do you think this idea works ok from a
> documentation point of view? By the way, I don't really know what I am doing
> with the yaml dt-bindings, I hope you won't be horrified by this series :-P
>
> I hope I was able to deliver the concept clearly, if not please just ask.
>
> Comments are very much appreciated.
>
> Thanks,
> Fab
>
> Fabrizio Castro (8):
> dt-bindings: display: Add bindings for LVDS bus-timings
> dt-bindings: display: Add idk-2121wr binding
> drm: Add bus timings helper
> drm: rcar-du: lvds: Add dual-LVDS panels support
> drm: bridge: thc63: Do not report input bus mode through bridge
> timings
> arm64: dts: renesas: Add EK874 board with idk-2121wr display support
> [HACK] arm64: dts: renesas: draak: Enable LVDS
> [HACK] arm64: dts: renesas: draak: Enable LVDS dual-link operation
>
> .../bindings/display/bus-timings/lvds.yaml | 38 +++++++
> .../display/panel/advantech,idk-2121wr.yaml | 90 ++++++++++++++++
> arch/arm64/boot/dts/renesas/Makefile | 3 +-
> .../boot/dts/renesas/r8a774c0-ek874-idk-2121wr.dts | 116 +++++++++++++++++++++
> arch/arm64/boot/dts/renesas/r8a77990-ebisu.dts | 21 +++-
> arch/arm64/boot/dts/renesas/r8a77995-draak.dts | 26 +++--
> drivers/gpu/drm/Makefile | 3 +-
> drivers/gpu/drm/bridge/thc63lvd1024.c | 9 +-
> drivers/gpu/drm/drm_bus_timings.c | 97 +++++++++++++++++
> drivers/gpu/drm/rcar-du/rcar_lvds.c | 110 +++++++++++--------
> include/drm/drm_bridge.h | 8 --
> include/drm/drm_bus_timings.h | 21 ++++
> 12 files changed, 473 insertions(+), 69 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/display/bus-timings/lvds.yaml
> create mode 100644 Documentation/devicetree/bindings/display/panel/advantech,idk-2121wr.yaml
> create mode 100644 arch/arm64/boot/dts/renesas/r8a774c0-ek874-idk-2121wr.dts
> create mode 100644 drivers/gpu/drm/drm_bus_timings.c
> create mode 100644 include/drm/drm_bus_timings.h
>
> --
> 2.7.4
prev parent reply other threads:[~2019-10-22 16:30 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-08-28 18:36 [PATCH v3 0/8] Add dual-LVDS panel support to EK874 Fabrizio Castro
2019-08-28 18:36 ` [PATCH v3 1/8] dt-bindings: display: Add bindings for LVDS bus-timings Fabrizio Castro
2019-08-29 7:57 ` Geert Uytterhoeven
2019-08-29 9:14 ` Fabrizio Castro
2019-08-29 14:03 ` Rob Herring
2019-08-29 14:38 ` Fabrizio Castro
2019-11-07 18:00 ` Laurent Pinchart
2019-12-06 15:11 ` Fabrizio Castro
2019-12-06 15:10 ` Fabrizio Castro
2019-08-28 18:36 ` [PATCH v3 2/8] dt-bindings: display: Add idk-2121wr binding Fabrizio Castro
2019-11-07 18:12 ` Laurent Pinchart
2019-12-06 15:17 ` Fabrizio Castro
2019-08-28 18:36 ` [PATCH v3 6/8] arm64: dts: renesas: Add EK874 board with idk-2121wr display support Fabrizio Castro
2019-11-07 19:55 ` Laurent Pinchart
2019-08-28 18:36 ` [PATCH v3 7/8] [HACK] arm64: dts: renesas: draak: Enable LVDS Fabrizio Castro
2019-11-07 19:57 ` Laurent Pinchart
2019-12-06 15:40 ` Fabrizio Castro
2019-08-28 18:36 ` [PATCH v3 8/8] [HACK] arm64: dts: renesas: draak: Enable LVDS dual-link operation Fabrizio Castro
2019-08-29 15:26 ` [PATCH v3 0/8] Add dual-LVDS panel support to EK874 Rob Herring
2019-09-02 10:01 ` Fabrizio Castro
2019-10-22 16:30 ` Fabrizio Castro [this message]
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=TYXPR01MB17753318ECA1556FE53C262AC0680@TYXPR01MB1775.jpnprd01.prod.outlook.com \
--to=fabrizio.castro@bp.renesas.com \
--cc=Chris.Paterson2@renesas.com \
--cc=Laurent.pinchart@ideasonboard.com \
--cc=a.hajda@samsung.com \
--cc=airlied@linux.ie \
--cc=biju.das@bp.renesas.com \
--cc=daniel@ffwll.ch \
--cc=devicetree@vger.kernel.org \
--cc=dri-devel@lists.freedesktop.org \
--cc=ebiharaml@si-linux.co.jp \
--cc=geert+renesas@glider.be \
--cc=horms@verge.net.au \
--cc=jacopo+renesas@jmondi.org \
--cc=kieran.bingham+renesas@ideasonboard.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-renesas-soc@vger.kernel.org \
--cc=maarten.lankhorst@linux.intel.com \
--cc=magnus.damm@gmail.com \
--cc=mark.rutland@arm.com \
--cc=maxime.ripard@bootlin.com \
--cc=robh+dt@kernel.org \
--cc=sam@ravnborg.org \
--cc=sean@poorly.run \
--cc=thierry.reding@gmail.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).