Re: [PATCH v2 1/2] dt-bindings: drm/bridge: anx7625: add DPI flag and swing setting

[Xin Ji]

On Sat, Jan 23, 2021 at 12:16:02AM +0800, Rob Herring wrote:
> On Tue, Jan 12, 2021 at 2:57 AM Xin Ji <xji@xxxxxxxxxxxxxxxx> wrote:
> >
> > Hi Rob Herring, thanks for the comments.
> >
> > On Mon, Jan 11, 2021 at 04:14:35PM -0600, Rob Herring wrote:
> > > On Thu, Dec 31, 2020 at 10:21:12AM +0800, Xin Ji wrote:
> > > > Add DPI flag for distinguish MIPI input signal type, DSI or DPI. Add
> > > > swing setting for adjusting DP tx PHY swing
> > > >
> > > > Signed-off-by: Xin Ji <xji@xxxxxxxxxxxxxxxx>
> > > > ---
> > > >  .../bindings/display/bridge/analogix,anx7625.yaml  | 25 ++++++++++++++++++++--
> > > >  1 file changed, 23 insertions(+), 2 deletions(-)
> > > >
> > > > diff --git a/Documentation/devicetree/bindings/display/bridge/analogix,anx7625.yaml b/Documentation/devicetree/bindings/display/bridge/analogix,anx7625.yaml
> > > > index 60585a4..4eb0ea3 100644
> > > > --- a/Documentation/devicetree/bindings/display/bridge/analogix,anx7625.yaml
> > > > +++ b/Documentation/devicetree/bindings/display/bridge/analogix,anx7625.yaml
> > > > @@ -34,6 +34,16 @@ properties:
> > > >      description: used for reset chip control, RESET_N pin B7.
> > > >      maxItems: 1
> > > >
> > > > +  analogix,swing-setting:
> > > > +    type: uint8-array
> > >
> > > Humm, this should have be rejected by the meta-schema.
> > We needs define an array to adjust DP tx PHY swing, the developer hopes these
> > settings are changeable, so I moved the register data to DT. Can you
> > give me some suggestion if it is rejected by the meta-schema?
> > >
> > > > +    $ref: /schemas/types.yaml#/definitions/uint32-array
> > >
> > > This is how types are defined other than boolean or nodes (object).
> > >
> > > > +    description: an array of swing register setting for DP tx PHY
> > > > +
> > > > +  analogix,mipi-dpi-in:
> > > > +    type: int
> > > > +    $ref: /schemas/types.yaml#/definitions/uint32
> > > > +    description: indicate the MIPI rx signal type is DPI or DSI
> > >
> > > Why does this need to be in DT, you should be able to determine this
> > > based on what you are connected to.
> > As the anx7625 can receive MIPI DSI and DPI data (depends on hardware
> > implement, we have a project which have two anx7625, one is DSI input,
> > the other is DPI input), we needs to let driver know what kind of MIPI
> > rx signal input. And there is no other way to tell driver the MIPI rx
> > signal type, we needs define this flag.
> 
> That's only true if what's driving the output is a single h/w block
> that can drive either. But typically you have 2 blocks: an LCD
> controller driving parallel signals and a DSI controller in front of
> it doing parallel to DSI conversion. The anx7625 would be connected to
> the LCD controller or DSI controller via the graph binding depending
> on the h/w connection.
> 
> However, if you do need this, then let's extend video-interfaces.yaml
> 'bus-type' to include DSI (it already has parallel).
> 
> Rob
Hi Rob, thanks, I'll add 'bus-type' in the next version.
Thanks,
Xin