Re: [PATCH v4 2/6] media: max9286: Implement set_routing

Laurent Pinchart
2021-12-17T02:24:15Z

On Fri, Dec 17, 2021 at 04:18:51AM +0200, Laurent Pinchart wrote:
> Hi Jacopo,
>
> Another comment.
>
> On Fri, Dec 17, 2021 at 03:56:48AM +0200, Laurent Pinchart wrote:
> > On Thu, Dec 16, 2021 at 06:47:42PM +0100, Jacopo Mondi wrote:
> > > Add the set_routing() subdev operation to allow userspace to configure
> > > routing on the max9286 deserializer.
> > >
> > > Implement route verification but do not take routing into consideration
> > > when configuring the CSI-2 output and pixel rate yet.
> > >
> > > Signed-off-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
> > > ---
> > > drivers/media/i2c/max9286.c | 89 ++++++++++++++++++++++++++++++++++++-
> > > 1 file changed, 87 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/drivers/media/i2c/max9286.c b/drivers/media/i2c/max9286.c
> > > index 1b9ff537d08e..eb76acdb2cd9 100644
> > > --- a/drivers/media/i2c/max9286.c
> > > +++ b/drivers/media/i2c/max9286.c
> > > @@ -832,6 +832,91 @@ static int max9286_get_fmt(struct v4l2_subdev *sd,
> > > return 0;
> > > }
> > >
> > > +static int max9286_routing_validate(struct max9286_priv *priv,
> > > + struct v4l2_subdev_krouting *routing)
> > > +{
> > > + unsigned int i;
> > > + int ret;
> > > +
> > > + ret = v4l2_subdev_routing_validate_1_to_1(routing);
> > > + if (ret)
> > > + return ret;
> > > +
> > > + /*
> > > + * Make sure all routes points to the single source pad which can have
> > > + * up to 4 streams. All routes shall start from a sink pad and shall not
> > > + * have more than one sink stream. The GMSL link for the sink has to be
> > > + * enabled.
> > > + */
> > > + for (i = 0; i < routing->num_routes; ++i) {
> > > + const struct v4l2_subdev_route *route = &routing->routes[i];
> > > + struct max9286_source *source = &priv->sources[i];
>
> There's no need to initialize source here.
>
> > > +
> > > + if (route->source_pad != MAX9286_SRC_PAD ||
> > > + route->source_stream > 4) {
> > > + dev_err(&priv->client->dev,
> > > + "Invalid (%u,%u) source in route %u\n",
> > > + route->source_pad, route->source_stream, i);
> > > + return -EINVAL;
> > > + }
> > > +
> > > + if (route->sink_pad >= MAX9286_N_SINKS ||
> > > + route->sink_stream != 0) {
> > > + dev_err(&priv->client->dev,
> > > + "Invalid (%u,%u) sink in route %u\n",
> > > + route->sink_pad, route->sink_stream, i);
> > > + return -EINVAL;
> > > + }
> > > +
> > > + source = &priv->sources[route->sink_pad];
> > > + if (!source->fwnode) {
> > > + dev_err(&priv->client->dev,
> > > + "Cannot set route for non-active source %u\n",
> > > + route->sink_pad);
> > > + return -EINVAL;
> > > + }
> > > + }
> >
> > Apart from from possibly using the new helper I've submitted, this looks
> > fine.
>
> The helper should allow to drop the source_pad and sink_pad checks, but
> the source_stream and sink_stream checks are still needed. This may be
> possible to factorize in the helper too, let's see when we'll have more
> use cases.
>
> > > +
> > > + return 0;
> > > +}
> > > +
> > > +static int _max9286_set_routing(struct v4l2_subdev *sd,
> > > + struct v4l2_subdev_state *state,
> > > + struct v4l2_subdev_krouting *routing)
> > > +{
> > > + struct max9286_priv *priv = sd_to_max9286(sd);
> > > + int ret;
> > > +
> > > + ret = max9286_routing_validate(priv, routing);
> > > + if (ret)
> > > + return ret;
> > > +
> > > + /* Re-initialize the format on a routing change. */
> > > + ret = v4l2_subdev_set_routing_with_fmt(sd, state, routing,
> > > + &max9286_default_format);
> > > + if (ret)
> > > + return ret;
> > > +
> > > + return 0;
> > > +}
> > > +
> > > +static int max9286_set_routing(struct v4l2_subdev *sd,
> > > + struct v4l2_subdev_state *state,
> > > + enum v4l2_subdev_format_whence which,
> > > + struct v4l2_subdev_krouting *routing)
> > > +{
> > > + struct max9286_priv *priv = sd_to_max9286(sd);
> > > + unsigned int i;

priv and i are not used (they will be used in a patch later in the
series, so should be moved there).

> > > + int ret;
> > > +
> > > + v4l2_subdev_lock_state(state);
> > > +
> >
> > I'd drop the blank line, or add one before the unlock call.
> >
> > > + ret = _max9286_set_routing(sd, state, routing);
> > > + v4l2_subdev_unlock_state(state);
> > > +
> > > + return ret;
> > > +}
> > > +
> > > static int max9286_init_cfg(struct v4l2_subdev *sd,
> > > struct v4l2_subdev_state *state)
> > > {
> > > @@ -858,8 +943,7 @@ static int max9286_init_cfg(struct v4l2_subdev *sd,
> > > routing.routes = routes;
> > >
> > > v4l2_subdev_lock_state(state);
> > > - ret = v4l2_subdev_set_routing_with_fmt(sd, state, &routing,
> > > - &max9286_default_format);
> > > + ret = _max9286_set_routing(sd, state, &routing);
> > > v4l2_subdev_unlock_state(state);

This is identical to max9286_set_routing(), you could call it directly,
and then merge _max9286_set_routing() and max9286_set_routing().

> > >
> > > return ret;
> > > @@ -874,6 +958,7 @@ static const struct v4l2_subdev_pad_ops max9286_pad_ops = {
> > > .enum_mbus_code = max9286_enum_mbus_code,
> > > .get_fmt = max9286_get_fmt,
> > > .set_fmt = max9286_set_fmt,
> > > + .set_routing = max9286_set_routing,
> > > };
> > >
> > > static const struct v4l2_subdev_ops max9286_subdev_ops = {

--
Regards,

Laurent Pinchart