Hi Laurent,
On 2017-12-20 20:06:13 +0200, Laurent Pinchart wrote:
> Hi Niklas,
>
> On Friday, 15 December 2017 16:23:10 EET Niklas Söderlund wrote:
> > On 2017-12-15 15:06:44 +0100, Hans Verkuil wrote:
> > > Niklas,
> > >
> > > Did you look at this? If I should take it, can you Ack it? If you are
> > > going to squash or add it to our of your own patch series, then let me
> > > know and I can remove it from my todo queue.
> >
> > I did look at it and talked to Jacobo about it. I think I have a better
> > solution to his problem which I hope to try out in the near future. If
> > my workaround turns out to not solve his problem I will squash this in
> > when I resend the rcar-csi2 patch-set so in any case I think you can
> > drop it from your todo queue.
> >
> > The reason I'm a bit reluctant to ack this straight away is that I think
> > it's kind of good that rcar-csi2 fails to probe if it finds no endpoints
> > to work with, there is little use for the driver instance then. The
> > problem Jacobo is trying to fix is related to how the rcar-vin Gen3
> > group parses DT and I made a small mistake there which was discovered by
> > Jacobo. And since the original fault is in the rcar-vin driver I think
> > the issue should be fixed in that driver.
>
> How do you plan to handle the case where only one CSI-2 receiver has a
> connected input ?
I'm sorry, I don't understand this question I think. If there only is
one CSI-2 receiver with connected endpoints, should that not be the only
hardware the driver handles? What would be the reason to enable a CSI-2
device in DT and not connect endpoints to it?
>
> > > On 05/12/17 21:41, Jacopo Mondi wrote:
> > >> When rcar-csi interface is not connected to any endpoint, it fails and
> > >> bails out from probe before registering its own video subdevice.
> > >> This prevents rcar-vin registered notifier from completing and no
> > >> subdevice is ever registered, also for other properly connected csi
> > >> interfaces.
> > >>
> > >> Fix this not returning an error when no endpoint is connected to a csi
> > >> interface and let the driver complete its probe function and register
> > >> its own video subdevice.
> > >>
> > >> ---
> > >> Niklas,
> > >>
> > >> please squash this patch in your next rcar-csi2 series (if you like
> > >> it ;)
> > >>
> > >> As we have discussed this is particularly useful for gmsl setup, where
> > >> adv748x is connected to CSI20 and max9286 to CSI40/CSI41. If we disable
> > >> adv748x from DTS we need CSI20 probe to complete anyhow otherwise no
> > >> subdevice gets registered for the two deserializers.
> > >>
> > >> Please note we cannot disable CSI20 entirely otherwise VIN's graph
> > >> parsing breaks.
> > >>
> > >> Thanks
> > >>
> > >> j
> > >>
> > >> ---
> > >>
> > >> drivers/media/platform/rcar-vin/rcar-csi2.c | 4 ++--
> > >> 1 file changed, 2 insertions(+), 2 deletions(-)
> > >>
> > >> diff --git a/drivers/media/platform/rcar-vin/rcar-csi2.c
> > >> b/drivers/media/platform/rcar-vin/rcar-csi2.c index 2793efb..90c4062
> > >> 100644
> > >> --- a/drivers/media/platform/rcar-vin/rcar-csi2.c
> > >> +++ b/drivers/media/platform/rcar-vin/rcar-csi2.c
> > >> @@ -928,8 +928,8 @@ static int rcar_csi2_parse_dt(struct rcar_csi2
> > >> *priv)
> > >>
> > >> ep = of_graph_get_endpoint_by_regs(priv->dev->of_node, 0, 0);
> > >> if (!ep) {
> > >> - dev_err(priv->dev, "Not connected to subdevice\n");
> > >> - return -EINVAL;
> > >> + dev_dbg(priv->dev, "Not connected to subdevice\n");
> > >> + return 0;
> > >> }
> > >>
> > >> ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(ep), &v4l2_ep);
>
> --
> Regards,
>
> Laurent Pinchart
>
--
Regards,
Niklas Söderlund
