On Wed, Aug 15, 2018 at 4:45 PM, Rob Herring robh@kernel.org wrote:
On Tue, Aug 14, 2018 at 10:48 PM Sam Ravnborg sam@ravnborg.org wrote:
[...]
One DT related Q: The LCD Controller supports BGR565, but as this is less common some HW implmentations exchange R and B, expessed in the old binding as wiring-mode like this:
atmel,lcd-wiring-mode: lcd wiring mode "RGB" or "BRG"How can we express this wiring-mode in a generic way, both in DT and in code? Is it something that in DRM belongs to the panel, the encoder, the connector, or? And can any of the exisitng flags be used?
I thought we had come up with a common definition, but I guess it didn't make it upstream. It's definitely needed and I've been rejecting anything new that's vendor specific.
I found this: https://patchwork.ozlabs.org/patch/659570/ The suggestion with a boolean seems simple and I will try that.
That's really too simple to be common. There's been a few other attempts[1][2][3] (for Atmel HLCDC in fact) with [3] probably being the closest to merging. The binding looked fine to me, but looks like the DRM implementation had some issues.
Rob
[1] https://lists.freedesktop.org/archives/dri-devel/2018-April/173089.html [2] https://patchwork.kernel.org/patch/9965079/ [3] http://lists.infradead.org/pipermail/linux-arm-kernel/2018-March/568731.html
There's a standardized bus_format for drm_panel. IIrc there's been discussions to add something similar to drm_bridge, but didn't go all that far for reasons.
Lots of drivers just handle this internally in some way. So no idea why this all got stalled. -Daniel