Messages in this thread Patch in this message | | | Subject | Re: [PATCH] v4l: async: make v4l2 coexists with devicetree nodes in a dt overlay | From | Javier Martinez Canillas <> | Date | Wed, 23 Nov 2016 11:25:39 -0300 |
| |
Hello Javi,
On 11/23/2016 07:09 AM, Javi Merino wrote: > In asd's configured with V4L2_ASYNC_MATCH_OF, if the v4l2 subdev is in > a devicetree overlay, its of_node pointer will be different each time > the overlay is applied. We are not interested in matching the > pointer, what we want to match is that the path is the one we are > expecting. Change to use of_node_cmp() so that we continue matching > after the overlay has been removed and reapplied. >
I'm still not that familiar with DT overlays (and I guess others aren't either) so I think that including an example of a base tree and overlay DTS where this is an issue, could make things more clear in the commit.
IIUC, it should be something like this?
-- base tree --
&i2c1 { camera: camera@10 { reg = <0x10>; port { cam_ep: endpoint { ... }; }; }; };
&media_bridge { ... ports { port@0 { reg = <0>; ep: endpoint { remote-endpoint = <&cam_ep>; }; }; }; };
-- overlay --
/plugin/; / { ... fragment@0 { target = <&camera>; __overlay__ { compatible = "foo,bar"; ... port { cam_ep: endpoint { ... }; }; }; } }
> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> > Cc: Javier Martinez Canillas <javier@osg.samsung.com> > Cc: Sakari Ailus <sakari.ailus@linux.intel.com> > Signed-off-by: Javi Merino <javi.merino@kernel.org> > --- > Hi, > > I feel it is a bit of a hack, but I couldn't think of anything better. > I'm ccing devicetree@ and Pantelis because there may be a simpler > solution. >
I also couldn't think a better way to do this, since IIUC the node's name is the only thing that doesn't change, and is available at the time the bridge driver calls v4l2_async_notifier_register() when parsing the base tree.
> drivers/media/v4l2-core/v4l2-async.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/media/v4l2-core/v4l2-async.c b/drivers/media/v4l2-core/v4l2-async.c > index 5bada20..d33a17c 100644 > --- a/drivers/media/v4l2-core/v4l2-async.c > +++ b/drivers/media/v4l2-core/v4l2-async.c > @@ -42,7 +42,8 @@ static bool match_devname(struct v4l2_subdev *sd, > > static bool match_of(struct v4l2_subdev *sd, struct v4l2_async_subdev *asd) > { > - return sd->of_node == asd->match.of.node; > + return !of_node_cmp(of_node_full_name(sd->of_node), > + of_node_full_name(asd->match.of.node)); > } > > static bool match_custom(struct v4l2_subdev *sd, struct v4l2_async_subdev *asd) >
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Best regards, -- Javier Martinez Canillas Open Source Group Samsung Research America
| |