Hi Laurent,
On 19-05-16 19:36, Laurent Pinchart wrote:
> Hi Marco,
>
> Thank you for the patch.
Thanks for the review and sorry for the delayed reply.
> On Mon, Apr 15, 2019 at 02:44:02PM +0200, Marco Felsch wrote:
> > Currently every driver needs to parse the connector endpoints by it self.
>
> s/it self/itself/
>
> > This is the initial work to make this generic. The generic connector has
> > some common fields and some connector specific parts. The generic one
> > includes:
> > - type
> > - label
> > - remote_port (the port where the connector is connected to)
> > - remote_id (the endpoint where the connector is connected to)
>
> This assumes a single connection between a connector and a remote port,
> and a single port on the connector side. Is this guaranteed ? For the
> mini-DIN-4 connectors (often used for S-Video) for instance, I recall
> from the extensive discussions we had in the past that they should be
> modeled with two pins, one for the Y component and one for C components.
> The rationale for this is to support systems where such a connector
> could be used to carry S-Video, but also two composite video signals
> (usually through an external adapter from 2 RCA female connectors to one
> S-Video male connector) that would be routed to two separate video
> decoders (or two different inputs of the same video decoder). Other
> topologies may be possible too.
I got your concerns and I also remember the tvp5150 port bindings
myself in the past. Do you know how often such a setup you described
above happens these days? I would rather add more documentation to the
bindings [1] and add a check to v4l2_fwnode_parse_connector() to
guarantee that one port has only one endpoint. Because I don't think
that analog connectors has a bright future these days.
[1] Documentation/devicetree/bindings/display/connector/ \
analog-tv-connector.txt
> > The specific fields are within a union, since only one of them can be
> > available at the time. Since this is the initial support the patch adds
> > only the analog-connector specific ones.
> >
> > Signed-off-by: Marco Felsch <m.felsch@xxxxxxxxxxxxxx>
> > Reviewed-by: Jacopo Mondi <jacopo@xxxxxxxxxx>
> > ---
> > [1] https://patchwork.kernel.org/cover/10794703/
> >
> > v6:
> > - fix some spelling and style issues
> > - rm unnecessary comments
> > - drop vga and dvi connector
> >
> > v2-v4:
> > - nothing since the patch was squashed from series [1] into this
> > series.
> >
> > include/media/v4l2-connector.h | 30 ++++++++++++++++++++++++++++++
> > include/media/v4l2-fwnode.h | 33 +++++++++++++++++++++++++++++++++
> > 2 files changed, 63 insertions(+)
> > create mode 100644 include/media/v4l2-connector.h
> >
> > diff --git a/include/media/v4l2-connector.h b/include/media/v4l2-connector.h
> > new file mode 100644
> > index 000000000000..3a951c54f50e
> > --- /dev/null
> > +++ b/include/media/v4l2-connector.h
> > @@ -0,0 +1,30 @@
> > +/* SPDX-License-Identifier: GPL-2.0-only */
> > +/*
> > + * v4l2-connector.h
> > + *
> > + * V4L2 connector types.
> > + *
> > + * Copyright 2019 Pengutronix, Marco Felsch <kernel@xxxxxxxxxxxxxx>
> > + */
> > +
> > +#ifndef V4L2_CONNECTOR_H
> > +#define V4L2_CONNECTOR_H
> > +
> > +#define V4L2_CONNECTOR_MAX_LABEL 41
>
> Hans pointed out this was a weird number. Should you turn the label
> field into a pointer to make this more generic (with a
> v4l2_fwnode_connector_cleanup() function then) ?
Yes, that would be the better approach. I will change that.
Regards,
Marco
> > +
> > +/**
> > + * enum v4l2_connector_type - connector type
> > + * @V4L2_CON_UNKNOWN: unknown connector type, no V4L2 connetor configuration
> > + * @V4L2_CON_COMPOSITE: analog composite connector
> > + * @V4L2_CON_SVIDEO: analog svideo connector
> > + * @V4L2_CON_HDMI: digital hdmi connector
> > + */
> > +enum v4l2_connector_type {
> > + V4L2_CON_UNKNOWN,
> > + V4L2_CON_COMPOSITE,
> > + V4L2_CON_SVIDEO,
> > + V4L2_CON_HDMI,
> > +};
> > +
> > +#endif /* V4L2_CONNECTOR_H */
> > +
> > diff --git a/include/media/v4l2-fwnode.h b/include/media/v4l2-fwnode.h
> > index 6c07825e18b9..f4df1b95c5ef 100644
> > --- a/include/media/v4l2-fwnode.h
> > +++ b/include/media/v4l2-fwnode.h
> > @@ -22,6 +22,7 @@
> > #include <linux/list.h>
> > #include <linux/types.h>
> >
> > +#include <media/v4l2-connector.h>
> > #include <media/v4l2-mediabus.h>
> > #include <media/v4l2-subdev.h>
> >
> > @@ -126,6 +127,38 @@ struct v4l2_fwnode_link {
> > unsigned int remote_port;
> > };
> >
> > +/**
> > + * struct v4l2_fwnode_connector_analog - analog connector data structure
> > + * @supported_tvnorms: tv norms this connector supports, set to V4L2_STD_ALL
> > + * if no restrictions are specified.
> > + */
> > +struct v4l2_fwnode_connector_analog {
> > + v4l2_std_id supported_tvnorms;
> > +};
> > +
> > +/**
> > + * struct v4l2_fwnode_connector - the connector data structure
> > + * @remote_port: identifier of the remote endpoint port the connector connects
> > + * to
> > + * @remote_id: identifier of the remote endpoint the connector connects to
> > + * @label: connetor label
> > + * @type: connector type
> > + * @connector: connector configuration
> > + * @connector.analog: analog connector configuration
> > + * &struct v4l2_fwnode_connector_analog
> > + */
> > +struct v4l2_fwnode_connector {
> > + unsigned int remote_port;
> > + unsigned int remote_id;
> > + char label[V4L2_CONNECTOR_MAX_LABEL];
> > + enum v4l2_connector_type type;
> > +
> > + union {
> > + struct v4l2_fwnode_connector_analog analog;
> > + /* future connectors */
> > + } connector;
> > +};
> > +
> > /**
> > * v4l2_fwnode_endpoint_parse() - parse all fwnode node properties
> > * @fwnode: pointer to the endpoint's fwnode handle
>
> --
> Regards,
>
> Laurent Pinchart
>
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