[PATCH 01/11] staging: drm/imx: Add LDB support
Philipp Zabel
p.zabel at pengutronix.de
Wed Mar 27 02:38:29 EST 2013
Hi Thomas,
Am Dienstag, den 26.03.2013, 15:34 +0100 schrieb Thomas Petazzoni:
> Dear Philipp Zabel,
>
> On Tue, 26 Mar 2013 15:13:56 +0100, Philipp Zabel wrote:
>
> > +/*
> > + * For a device declaring compatible = "fsl,imx6q-ldb", "fsl,imx53-ldb",
> > + * of_match_device will walk through this list and take the first entry
> > + * matching any of its compatible values. Therefore, the more generic
> > + * entries (in this case fsl,imx53-ldb) need to be ordered last.
> > + */
> > +static const struct of_device_id imx_ldb_dt_ids[] = {
> > + { .compatible = "fsl,imx6q-ldb", .data = imx6q_lvds_mux, },
> > + { .compatible = "fsl,imx53-ldb", .data = NULL, },
> > + { }
> > +};
>
> You probably want a new DT binding documentation in
> Documentation/devicetree/bindings/.
Yes, this could be something along the lines of:
Device-Tree bindings for LVDS Display Bridge (ldb)
LVDS Display Bridge
===================
The LVDS Display Bridge device tree node contains up to two lvds-channel
nodes describing each of the two LVDS encoder channels of the bridge.
Required properties:
- #address-cells : should be <1>
- #size-cells : should be <0>
- compatible : should be "fsl,imx53-ldb" or "fsl,imx6q-ldb".
Both LDB versions are similar, but i.MX6 has an additional
multiplexer in the front to select any of the four IPU display
interfaces as input.
- gpr : should be <&gpr> on i.MX53 and i.MX6q.
The phandle points to the iomuxc-gpr region containing the LVDS
control register.
- clocks : phandles pointing to the LDB display interface clocks, LDB source
selector clocks
- clocks, clock-names : phandles to the LDB divider and selector clocks and to
the display interface selector clocks, as described in
Documentation/devicetree/bindings/clock/clock-bindings.txt
The following clocks are expected on i.MX53:
"di0_pll" - LDB LVDS channel 0 mux
"di1_pll" - LDB LVDS channel 1 mux
"di0" - LDB LVDS channel 0 gate
"di1" - LDB LVDS channel 1 gate
"di0_sel" - IPU1 DI0 mux
"di1_sel" - IPU1 DI1 mux
On i.MX6q the following additional clocks are needed:
"di2_sel" - IPU2 DI0 mux
"di3_sel" - IPU2 DI1 mux
The needed clock numbers for each are documented in
Documentation/devicetree/bindings/clock/imx5-clock.txt, and in
Documentation/devicetree/bindings/clock/imx6q-clock.txt.
Optional properties:
- pinctrl-names : should be "default" on i.MX53, not used on i.MX6q
- pinctrl-0 : should be <&pinctrl_lvds1_1> on i.MX53, not used on i.MX6q
- fsl,dual-channel : boolean. if it exists, only LVDS channel 0 should
be configured - one input will be distributed on both outputs in dual
channel mode
LVDS Channel
============
Each LVDS Channel has to contain a display-timings node that describes the
video timings for the connected LVDS display. For detailed information,
have a look at Documentation/devicetree/bindings/video/display-timing.txt.
Required properties:
- reg : should be <0> or <1>
- crtcs : a list of phandles with index pointing to the IPU display interfaces
that can be used as video source for this channel.
- fsl,data-mapping : should be "spwg" or "jeida"
This describes how the color bits are laid out in the
serialized LVDS signal.
- fsl,data-width : should be <18> or <24>
Example:
gpr: iomuxc-gpr at 53fa8000 {
/* ... */
};
ldb: ldb at 53fa8008 {
#address-cells = <1>;
#size-cells = <0>;
compatible = "fsl,imx53-ldb";
gpr = <&gpr>;
clocks = <&clks 122>, <&clks 120>,
<&clks 115>, <&clks 116>,
<&clks 123>, <&clks 85>;
clock-names = "di0_pll", "di1_pll",
"di0_sel", "di1_sel",
"di0", "di1";
lvds-channel at 0 {
reg = <0>;
crtcs = <&ipu 0>;
fsl,data-mapping = "spwg";
fsl,data-width = <24>;
display-timings {
/* ... */
};
};
lvds-channel at 1 {
reg = <1>;
crtcs = <&ipu 1>;
fsl,data-mapping = "spwg";
fsl,data-width = <24>;
display-timings {
/* ... */
};
};
};
thanks
Philipp
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