Hello,
This patch series adds support for LVDS mode selection in the R-Car DU driver.
Compared to v1, the LVDS panel DT bindings (02/13) have been reworked to
document common panel properties in a common file (01/13), with Mitsubishi
panels bindings now properly documented (03/13). Compared to the existing DPI
panel bindings that are currently abused by the R-Car DU driver for LVDS
panel, these new bindings specify the LVDS more explicitly.
The bindings are based on the relevant standards I have been able to find, as
well as on existing LVDS-related code and DT bindings available in the
mainline kernel. Those include
- the LVDS formats MEDIA_BUS_FMT_RGB666_1X7X3_SPWG,
MEDIA_BUS_FMT_RGB888_1X7X4_SPWG and MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA
(Documentation/media/uapi/v4l/subdev-formats.rst)
- iMX display DT bindings available in
(Documentation/devicetree/bindings/display/imx/ldb.txt)
- the drivers/gpu/drm/imx/ driver
In addition to the three modes specified in the LVDS panel DT bindings, the
Renesas R-Car DU also supports the following two modes.
Slot 0 1 2 3 4 5 6
________________ _________________
Clock \_______________________/
______ ______ ______ ______ ______ ______ ______
DATA0 ><_CTL0_><__R7__><__R6__><__R5__><__R4__><__R3__><__R2__><
DATA1 ><_CTL1_><__G7__><__G6__><__G5__><__G4__><__G3__><__G2__><
DATA2 ><_CTL2_><__B7__><__B6__><__B5__><__B4__><__B3__><__B2__><
DATA3 ><_CTL3_><__B1__><__B0__><__G1__><__G0__><__R1__><__R0__><
______ ______ ______ ______ ______ ______ ______
DATA0 ><_CTL0_><__R5__><__R4__><__R3__><__R2__><__R1__><__R0__><
DATA1 ><_CTL1_><__G5__><__G4__><__G3__><__G2__><__G1__><__G0__><
DATA2 ><_CTL2_><__B5__><__B4__><__B3__><__B2__><__B1__><__B0__><
DATA3 ><_CTL3_><__B7__><__B6__><__G7__><__G6__><__R7__><__R6__><
and their mirrored version.
I haven't been able to find any standard defining those data mappings, nor any
panel using them. The control signals positions correspond to DC-balanced LVDS
(see figure 18 on page 19 of http://www.ti.com/lit/ds/symlink/ds90cf388.pdf),
but the R-Car DU doesn't support DC-balanced LVDS as far as I can tell, so
it's not a match. If anyone knows of other devices supporting these data
mappings or of standards defining them I would appreciate the information and
will update the bindings accordingly.
Patches 04/13 to 06/13 add a new DRM panel driver for LVDS panels compatible
with the DT bindings. Patches 07/13 to 09/13 update the device tree of the
R-Car H3 Salvator-X board to add panel backlight support, and patch 10/13
switches two Mitsubishi panels to use the new bindings. This series doesn't
strictly depend on them so they can be merged separately at a later point if
needed.
Patches 11/13 to 13/13 finally move the R-Car DU driver to use the DRM panel
API, and add support for LVDS mode selection.
Laurent Pinchart (13):
devicetree/bindings: display: Document common panel properties
devicetree/bindings: display: Add bindings for LVDS panels
devicetree/bindings: display: Add bindings for two Mitsubishi panels
drm: Add data mirror bus flag
drm: panels: Constify device node argument to of_drm_find_panel()
drm: panels: Add LVDS panel driver
arm64: dts: r8a7795: Add PWM support
arm64: dts: r8a7795: salvator-x: Add DU LVDS output endpoint
arm64: dts: r8a7795: salvator-x: Add panel backlight support
ARM: shmobile: dts: Switch to panel-lvds bindings for Mitsubishi
panels
drm: rcar-du: Switch to encoder .atomic_mode_set() helper function
drm: rcar-du: Use the DRM panel API
drm: rcar-du: Add support for LVDS mode selection
.../display/panel/mitsubishi,aa104xd12.txt | 47 ++++
.../display/panel/mitsubishi,aa121td01.txt | 47 ++++
.../bindings/display/panel/panel-common.txt | 91 +++++++
.../bindings/display/panel/panel-lvds.txt | 120 +++++++++
arch/arm/boot/dts/r8a77xx-aa104xd12-panel.dtsi | 3 +-
arch/arm/boot/dts/r8a77xx-aa121td01-panel.dtsi | 3 +-
arch/arm64/boot/dts/renesas/r8a7795-salvator-x.dts | 26 ++
arch/arm64/boot/dts/renesas/r8a7795.dtsi | 63 +++++
drivers/gpu/drm/drm_panel.c | 2 +-
drivers/gpu/drm/panel/Kconfig | 10 +
drivers/gpu/drm/panel/Makefile | 1 +
drivers/gpu/drm/panel/panel-lvds.c | 284 +++++++++++++++++++++
drivers/gpu/drm/rcar-du/Kconfig | 1 +
drivers/gpu/drm/rcar-du/rcar_du_encoder.c | 50 +++-
drivers/gpu/drm/rcar-du/rcar_du_encoder.h | 3 +
drivers/gpu/drm/rcar-du/rcar_du_hdmienc.c | 8 +-
drivers/gpu/drm/rcar-du/rcar_du_lvdscon.c | 68 ++---
drivers/gpu/drm/rcar-du/rcar_du_lvdsenc.c | 11 +-
drivers/gpu/drm/rcar-du/rcar_du_lvdsenc.h | 13 +
include/drm/drm_connector.h | 2 +
include/drm/drm_panel.h | 4 +-
21 files changed, 798 insertions(+), 59 deletions(-)
create mode 100644 Documentation/devicetree/bindings/display/panel/mitsubishi,aa104xd12.txt
create mode 100644 Documentation/devicetree/bindings/display/panel/mitsubishi,aa121td01.txt
create mode 100644 Documentation/devicetree/bindings/display/panel/panel-common.txt
create mode 100644 Documentation/devicetree/bindings/display/panel/panel-lvds.txt
create mode 100644 drivers/gpu/drm/panel/panel-lvds.c
--
Regards,
Laurent Pinchart
