On Thu, 24 Dec 2015 12:36:10 +0000
Russell King - ARM Linux <linux@xxxxxxxxxxxxxxxx> wrote:
> It seems that you're trying to work around a limitation in Linux by
> modifying the hardware representation...
Sorry to come back to this topic, but I think you are wrong.
Looking at the imx6 DTs, the problem comes from the display-subsystem
node which is a pure Linux specific software entity.
If you want to describe only the hardware in the DT, everything is
simple.
A IPU is a image controller with its sub-devices. Seen from the system, it
is like a 'board' with its devices (LCDs, camera...).
When 2 IPUs, there are 2 independant boards.
Here is what could be a pure hardware DT:
/* no display-subsystem */
ipu1: ipu@02400000 { /* image controller / board 1 */
compatible = "fsl,imx6q-ipu";
...
ports = <&ipu1_di0>, <&ipu1_di1>;
};
ipu1_di0: di@0 { /* display interface / crtc 1 */
compatible = "fsl,imx6q-di";
...
ipu1_di0_hdmi: endpoint@1 {
remote-endpoint = <&hdmi_mux_0>;
};
ipu1_di0_mipi: endpoint@2 {
remote-endpoint = <&mipi_mux_0>;
}
...
};
ipu1_di1: di@1 { /* display interface / crtc 2 */
compatible = "fsl,imx6q-di";
...
ipu1_di1_hdmi: endpoint@1 {
remote-endpoint = <&hdmi_mux_1>;
};
ipu1_di1_mipi: endpoint@2 {
remote-endpoint = <&mipi_mux_1>;
}
...
};
ipu2: ipu@02800000 { /* image controller / board 2 */
compatible = "fsl,imx6q-ipu";
...
ports = <&ipu2_di0>, <&ipu2_di1>;
};
ipu2_di0: di@0 { /* display interface / crtc 1 */
compatible = "fsl,imx6q-di";
...
ipu2_di0_hdmi: endpoint@1 {
remote-endpoint = <&hdmi_mux_2>;
};
ipu2_di0_mipi: endpoint@2 {
remote-endpoint = <&mipi_mux_2>;
}
...
};
ipu2_di1: di@1 { /* display interface / crtc 2 */
compatible = "fsl,imx6q-di";
...
ipu2_di1_hdmi: endpoint@1 {
remote-endpoint = <&hdmi_mux_3>;
};
ipu2_di1_mipi: endpoint@2 {
remote-endpoint = <&mipi_mux_3>;
}
...
};
Then, a standard component binding (port->parent) works fine...
(you may note that the same problem exists with audio: the
'simple-card' is also a pure Linux specific software entity)
--
Merry Christmas | ** Breizh ha Linux atav! **
Jef | http://moinejf.free.fr/
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