diff mbox

[v3,5/7] dt-bindings: display: Add common rotation property

Message ID 20170131160319.9695-6-noralf@tronnes.org (mailing list archive)
State New, archived
Headers show

Commit Message

Noralf Trønnes Jan. 31, 2017, 4:03 p.m. UTC
Display panels can be oriented many ways, especially in the embedded
world. The rotation property is a way to describe this orientation.
The counter clockwise direction is chosen because that's what fbdev
and drm use.

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
---
 Documentation/devicetree/bindings/display/display.txt | 4 ++++
 1 file changed, 4 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/display.txt

Comments

Rob Herring (Arm) Feb. 1, 2017, 5:41 p.m. UTC | #1
On Tue, Jan 31, 2017 at 05:03:17PM +0100, Noralf Trønnes wrote:
> Display panels can be oriented many ways, especially in the embedded
> world. The rotation property is a way to describe this orientation.
> The counter clockwise direction is chosen because that's what fbdev
> and drm use.

The h/w mounting is rotated counter clockwise, so the framebuffers' 
contents are rotated clockwise, right? 

> 
> Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
> ---
>  Documentation/devicetree/bindings/display/display.txt | 4 ++++

This is panel property, so bindings/display/panel/panel.txt.

>  1 file changed, 4 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/display/display.txt
> 
> diff --git a/Documentation/devicetree/bindings/display/display.txt b/Documentation/devicetree/bindings/display/display.txt
> new file mode 100644
> index 0000000..e2e6867
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/display/display.txt
> @@ -0,0 +1,4 @@
> +Common display properties
> +-------------------------
> +
> +- rotation:	Display rotation in degrees counter clockwise (0,90,180,270)
> -- 
> 2.10.2
> 
> --
> To unsubscribe from this list: send the line "unsubscribe devicetree" in
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Noralf Trønnes Feb. 3, 2017, 12:16 p.m. UTC | #2
Thierry, please have a look at this.
In which direction should we rotate to match how drm rotation works?


Den 01.02.2017 18.41, skrev Rob Herring:
> On Tue, Jan 31, 2017 at 05:03:17PM +0100, Noralf Trønnes wrote:
>> Display panels can be oriented many ways, especially in the embedded
>> world. The rotation property is a way to describe this orientation.
>> The counter clockwise direction is chosen because that's what fbdev
>> and drm use.
> The h/w mounting is rotated counter clockwise, so the framebuffers'
> contents are rotated clockwise, right?
>
>> Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
>> ---
>>   Documentation/devicetree/bindings/display/display.txt | 4 ++++
> This is panel property, so bindings/display/panel/panel.txt.
>
>>   1 file changed, 4 insertions(+)
>>   create mode 100644 Documentation/devicetree/bindings/display/display.txt
>>
>> diff --git a/Documentation/devicetree/bindings/display/display.txt b/Documentation/devicetree/bindings/display/display.txt
>> new file mode 100644
>> index 0000000..e2e6867
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/display/display.txt
>> @@ -0,0 +1,4 @@
>> +Common display properties
>> +-------------------------
>> +
>> +- rotation:	Display rotation in degrees counter clockwise (0,90,180,270)
>> -- 
>> 2.10.2
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe devicetree" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
Thierry Reding Feb. 6, 2017, 7:10 a.m. UTC | #3
On Fri, Feb 03, 2017 at 01:16:45PM +0100, Noralf Trønnes wrote:
> Thierry, please have a look at this.
> In which direction should we rotate to match how drm rotation works?
> 
> 
> Den 01.02.2017 18.41, skrev Rob Herring:
> > On Tue, Jan 31, 2017 at 05:03:17PM +0100, Noralf Trønnes wrote:
> > > Display panels can be oriented many ways, especially in the embedded
> > > world. The rotation property is a way to describe this orientation.
> > > The counter clockwise direction is chosen because that's what fbdev
> > > and drm use.
> > The h/w mounting is rotated counter clockwise, so the framebuffers'
> > contents are rotated clockwise, right?

Given that this describes the rotation of the panel, I think it should
be described in terms of how the panel is rotated, not how the
framebuffer needs to be rotated. Using counter-clockwise, as described
in this binding seems fine to me.

It would have to be up to fbdev and DRM/KMS to transform that into a
clockwise rotation for the framebuffer, CRTC, plane, ...

Ideally with some sort of helper.

Thierry

> > 
> > > Signed-off-by: Noralf Trønnes <noralf@tronnes.org>
> > > ---
> > >   Documentation/devicetree/bindings/display/display.txt | 4 ++++
> > This is panel property, so bindings/display/panel/panel.txt.
> > 
> > >   1 file changed, 4 insertions(+)
> > >   create mode 100644 Documentation/devicetree/bindings/display/display.txt
> > > 
> > > diff --git a/Documentation/devicetree/bindings/display/display.txt b/Documentation/devicetree/bindings/display/display.txt
> > > new file mode 100644
> > > index 0000000..e2e6867
> > > --- /dev/null
> > > +++ b/Documentation/devicetree/bindings/display/display.txt
> > > @@ -0,0 +1,4 @@
> > > +Common display properties
> > > +-------------------------
> > > +
> > > +- rotation:	Display rotation in degrees counter clockwise (0,90,180,270)
> > > -- 
> > > 2.10.2
> > > 
> > > --
> > > To unsubscribe from this list: send the line "unsubscribe devicetree" in
> > > the body of a message to majordomo@vger.kernel.org
> > > More majordomo info at  http://vger.kernel.org/majordomo-info.html
>
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/display/display.txt b/Documentation/devicetree/bindings/display/display.txt
new file mode 100644
index 0000000..e2e6867
--- /dev/null
+++ b/Documentation/devicetree/bindings/display/display.txt
@@ -0,0 +1,4 @@ 
+Common display properties
+-------------------------
+
+- rotation:	Display rotation in degrees counter clockwise (0,90,180,270)