Re: [PATCH v4 1/2] devicetree/bindings: display: Add document for rockchip RGB output

[Sandy Huang]

å 2018/8/27 15:11, Heiko Stuebner åé:
> Hi Sandy,
>
> trying to move this forward a bit :-)
Hi heiko,
ÂÂÂÂ update at version5 and add SPDX-License-Identifier tag.
> Am Mittwoch, 4. Juli 2018, 14:09:56 CEST schrieb Sandy Huang:
> > Hi Rob Herring,
> > Thanks for your review.
> >
> > å 2018/7/4 2:25, Rob Herring åé:
> >> On Tue, Jun 26, 2018 at 03:15:39PM +0800, Sandy Huang wrote:
> >>> This path add support rv1108 and px30 rgb output interface driver.
> >>
> >> Bindings are for h/w, not drivers.
> >>
> > I will update at next version as following:
> > This patch add support rv1108 and px30 rgb output interface
> >>>
> >>> Signed-off-by: Sandy Huang <hjc@xxxxxxxxxxxxxx>
> >>> Link: https://patchwork.freedesktop.org/patch/msgid/1509522765-118759-1-git-send-email-hjc@xxxxxxxxxxxxxx
> >>> ---
> >>>
> >>> Changes in v4: Add support px30
> >>> Changes in v3: None
> >>> Changes in v2: None
> >>>
> >>> .../bindings/display/rockchip/rockchip-rgb.txtÂÂÂÂ | 73 ++++++++++++++++++++++
> >>>ÂÂÂ 1 file changed, 73 insertions(+)
> >>>ÂÂÂ create mode 100644 Documentation/devicetree/bindings/display/rockchip/rockchip-rgb.txt
> >>>
> >>> diff --git a/Documentation/devicetree/bindings/display/rockchip/rockchip-rgb.txt b/Documentation/devicetree/bindings/display/rockchip/rockchip-rgb.txt
> >>> new file mode 100644
> >>> index 0000000..077b9ad
> >>> --- /dev/null
> >>> +++ b/Documentation/devicetree/bindings/display/rockchip/rockchip-rgb.txt
> >>> @@ -0,0 +1,73 @@
> >>> +Rockchip RV1108 RGB interface
> >>> +================================
> >>> +
> >>> +Required properties:
> >>> +- compatible: matching the soc type:
> >>> +ÂÂ Â- "rockchip,px30-rgb";
> >>> +ÂÂ Â- "rockchip,rv1108-rgb";
> >>
> >> This doesn't look right? What (and how) is getting programmed here
> >> because you don't have any register interface.
> >>
> > This is register for DRM encoder and connecter or bridge for some RGB
> > convert chips driver.
> > so far we don't have any register for rgb interface, but it's most
> > probable need to config some register for rgb interface in feauture for
> > rockchip platform.
>
> I think the basic-issue Rob was pointing out is that the devicetree
> describes hardware blocks and not the software representation.
>
> And the rgb output is not a separate block, but instead just a property
> of the vop itself, hence should possibly not have a separate "device".
>
> As I'm currently tinkering with rk3188 display support [0] - which only has
> rgb output at all - I modified your patch a bit to to showcase how that
> could look [1], where the soc vop struct simply has a feature flag
> indicating indicating a raw rgb output and the rgb driver then
> looks for bridges in the vop endpoints to distinguish them from
> soc-internals output encoders.
>
> Let me know what you think :-)
> Heiko
>
> [0] https://github.com/mmind/linux-rockchip/commits/wip/rk3188-lcdc
> [1] https://github.com/mmind/linux-rockchip/commit/fe74d2c4d76bcb6035b7207753e6afb85335b6cd
> needs also https://github.com/mmind/linux-rockchip/commit/c5a48c772f3564211dcd1ec71004de1d6dbb0307