[PATCH v3 2/6] dt-bindings: display: Add Synopsys DW MIPI DSI DRM bridge driver

[Rob Herring]

On Fri, Jun 09, 2017 at 10:43:07AM +0100, Jose Abreu wrote:
> Hello,
> 
> 
> On 09-06-2017 05:11, Archit Taneja wrote:
> > Hi Philippe, Rob,
> >
> > On 06/08/2017 09:10 PM, Rob Herring wrote:
> >> Seems strange there's not also a pixel or bit clock? Or this
> >> gets driven
> >> from the phy?
> >
> > Since you mention phy here, I wanted to share a concern with
> > the bindings.
> > These bindings don't have a separate PHY DT node. The PHY is
> > assumed as a
> > part of the IP when integrated by a SoC. There are already
> > rockchip and
> > hisil DSI bindings that use this IP but don't define a PHY node.
> >
> > It's a similar situation with the DW-HDMI bindings.
> >
> > For example, when the DW HDMI is integrated in rockchip or
> > renesas SoC, the
> > bindings "rockchip,rk3288-dw-hdmi" or "renesas,r8a7795-dw-hdmi"
> > are used,
> > and they don't have a separate PHY DT node.
> >
> > I wasn't sure whether this is the right way to proceed or not
> > for such IPs.
> > Some advice would help us here.
> >
> > Thanks,
> > Archit
> >
> 
> I just want to add that read/writes from/to phy are done using
> the controller (in HDMI and in MIPI DSI Host), so the only way to
> have a phy driver is that if some custom callbacks are provided
> or if the memory region is shared.
> 
> Anyway, I agree with Archit in the sense that phy + controller
> are highly tied. Also, these two "pieces" are SoC specific and
> sometimes very different between SoC's because they can be
> customized so I think a different compatible string suits well here.

When the phy is integrated like this, I agree that it doesn't make sense 
to have a separate phy node.

Rob