[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <YgbNfKiNkPmvaT1k@pendragon.ideasonboard.com>
Date: Fri, 11 Feb 2022 22:56:28 +0200
From: Laurent Pinchart <laurent.pinchart@...asonboard.com>
To: Paul Kocialkowski <paul.kocialkowski@...tlin.com>
Cc: linux-media@...r.kernel.org, devicetree@...r.kernel.org,
linux-arm-kernel@...ts.infradead.org, linux-sunxi@...ts.linux.dev,
linux-kernel@...r.kernel.org, linux-phy@...ts.infradead.org,
linux-clk@...r.kernel.org, linux-staging@...ts.linux.dev,
Yong Deng <yong.deng@...ewell.com>,
Mauro Carvalho Chehab <mchehab@...nel.org>,
Rob Herring <robh+dt@...nel.org>,
Maxime Ripard <mripard@...nel.org>,
Sakari Ailus <sakari.ailus@...ux.intel.com>,
Hans Verkuil <hans.verkuil@...co.com>,
Chen-Yu Tsai <wens@...e.org>,
Jernej Skrabec <jernej.skrabec@...il.com>,
Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
Helen Koike <helen.koike@...labora.com>,
Thomas Petazzoni <thomas.petazzoni@...tlin.com>,
Rob Herring <robh@...nel.org>
Subject: Re: [PATCH v2 07/66] dt-bindings: media: sun6i-a31-csi: Add MIPI
CSI-2 input port
On Fri, Feb 11, 2022 at 05:10:06PM +0100, Paul Kocialkowski wrote:
> Hi Laurent,
>
> Thanks for the review!
>
> On Mon 07 Feb 22, 18:03, Laurent Pinchart wrote:
> > Hi Paul,
> >
> > Thank you for the patch.
> >
> > On Sat, Feb 05, 2022 at 07:53:30PM +0100, Paul Kocialkowski wrote:
> > > The A31 CSI controller supports two distinct input interfaces:
> > > parallel and an external MIPI CSI-2 bridge. The parallel interface
> > > is often connected to a set of hardware pins while the MIPI CSI-2
> > > bridge is an internal FIFO-ish link. As a result, these two inputs
> > > are distinguished as two different ports.
> > >
> > > Note that only one of the two may be present on a controller instance.
> > > For example, the V3s has one controller dedicated to MIPI-CSI2 and one
> > > dedicated to parallel.
> >
> > Is it that only one of the two is present, or only one of the two is
> > connected ? In the latter case I'd make both ports required, but with
> > only one of them connected.
>
> There are situations where the actual pins for parallel (port@0) are missing
> and the controller is dedicated to its mipi csi-2 bridge (port@1), cases where
> the two are present and cases where the mipi csi-2 bridge doesn't exist.
> So all in all it's really legit that only one port may be defined.
The port could still exist internally in the IP core though. Of course
that's hard to tell.
> > > Update the binding with an explicit ports node that holds two distinct
> > > port nodes: one for parallel input and one for MIPI CSI-2.
> > >
> > > This is backward-compatible with the single-port approach that was
> > > previously taken for representing the parallel interface port, which
> > > stays enumerated as fwnode port 0.
> > >
> > > Note that additional ports may be added in the future, especially to
> > > support feeding the CSI controller's output to the ISP.
> > >
> > > Signed-off-by: Paul Kocialkowski <paul.kocialkowski@...tlin.com>
> > > Reviewed-by: Rob Herring <robh@...nel.org>
> > > Acked-by: Maxime Ripard <mripard@...nel.org>
> > > ---
> > > .../media/allwinner,sun6i-a31-csi.yaml | 60 +++++++++++++++----
> > > 1 file changed, 47 insertions(+), 13 deletions(-)
> > >
> > > diff --git a/Documentation/devicetree/bindings/media/allwinner,sun6i-a31-csi.yaml b/Documentation/devicetree/bindings/media/allwinner,sun6i-a31-csi.yaml
> > > index 8b568072a069..3cc61866ea89 100644
> > > --- a/Documentation/devicetree/bindings/media/allwinner,sun6i-a31-csi.yaml
> > > +++ b/Documentation/devicetree/bindings/media/allwinner,sun6i-a31-csi.yaml
> > > @@ -61,6 +61,34 @@ properties:
> > >
> > > additionalProperties: false
> > >
> > > + ports:
> > > + $ref: /schemas/graph.yaml#/properties/ports
> > > +
> > > + properties:
> > > + port@0:
> > > + $ref: "#/properties/port"
> > > + unevaluatedProperties: false
> > > +
> > > + port@1:
> > > + $ref: /schemas/graph.yaml#/$defs/port-base
> > > + description: MIPI CSI-2 bridge input port
> > > +
> > > + properties:
> > > + reg:
> > > + const: 1
> > > +
> > > + endpoint:
> > > + $ref: video-interfaces.yaml#
> > > + unevaluatedProperties: false
> > > +
> > > + additionalProperties: false
> > > +
> > > + anyOf:
> > > + - required:
> > > + - port@0
> > > + - required:
> > > + - port@1
> > > +
> > > required:
> > > - compatible
> > > - reg
> >
> > Shouldn't you specify that either port or ports is required, but not
> > both ? I'd also add a comment in the port node to tell it's deprecated,
> > and that ports should be used instead.
>
> Yes I agree on both points. I guess that should be a:
>
> oneOf:
> - required:
> - ports
> - required:
> - port
>
> (but feel free to correct me).
>
> > > @@ -89,19 +117,25 @@ examples:
> > > "ram";
> > > resets = <&ccu RST_BUS_CSI>;
> > >
> > > - port {
> > > - /* Parallel bus endpoint */
> > > - csi1_ep: endpoint {
> > > - remote-endpoint = <&adv7611_ep>;
> > > - bus-width = <16>;
> > > -
> > > - /*
> > > - * If hsync-active/vsync-active are missing,
> > > - * embedded BT.656 sync is used.
> > > - */
> > > - hsync-active = <0>; /* Active low */
> > > - vsync-active = <0>; /* Active low */
> > > - pclk-sample = <1>; /* Rising */
> > > + ports {
> > > + #address-cells = <1>;
> > > + #size-cells = <0>;
> > > +
> > > + port@0 {
> > > + reg = <0>;
> > > + /* Parallel bus endpoint */
> > > + csi1_ep: endpoint {
> > > + remote-endpoint = <&adv7611_ep>;
> > > + bus-width = <16>;
> > > +
> > > + /*
> > > + * If hsync-active/vsync-active are missing,
> > > + * embedded BT.656 sync is used.
> > > + */
> > > + hsync-active = <0>; /* Active low */
> > > + vsync-active = <0>; /* Active low */
> > > + pclk-sample = <1>; /* Rising */
> >
> > Wrong indentation.
>
> The double-space before /* Rising */ or something with the heading indent?
The heading has one extra space for all three lines, they should be
aligned to the / of /*, not to the *.
> > > + };
> > > };
> > > };
> > > };
--
Regards,
Laurent Pinchart
Powered by blists - more mailing lists