| Message ID | 1583838364-12932-2-git-send-email-prabhakar.mahadev-lad.rj@bp.renesas.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | media: rcar-vin: Enable MEDIA_BUS_FMT_SRGGB8_1X8 format and support for matching fwnode against endpoints/nodes | expand |
Hi Lad, Thanks for your work. On 2020-03-10 11:06:02 +0000, Lad Prabhakar wrote: > The rcar-csi2 driver uses the v4l2-async framework to do endpoint matching > instead of node matching. This is needed as it needs to work with the > adv748x driver which register it self in v4l2-async using endpoints > instead of nodes. The reason for this is that from a single DT node it > creates multiple subdevices, one for each endpoint. > > But when using subdevs which register itself in v4l2-async using nodes, > the rcar-csi2 driver failed to find the matching endpoint because the > match.fwnode was pointing to remote endpoint instead of remote parent > port. > > This commit adds support in rcar-csi2 driver to handle both the cases > where subdev registers in v4l2-async using endpoints/nodes, by using > match_type as V4L2_ASYNC_MATCH_CUSTOM and implementing the match() > callback to compare the fwnode of either remote/parent. This is a novel approach to the solution, and I won't object to it out right. But I think the proper solution is to move this logic into v4l2-async instead of adding a custom match handler in rcar-csi2. Think of the reveres use-case, a different CSI-2 receiver who wish to use the ADV748x would still have this node vs. endpoint issue. > > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> > --- > drivers/media/platform/rcar-vin/rcar-csi2.c | 41 ++++++++++++++++++++++++++--- > 1 file changed, 38 insertions(+), 3 deletions(-) > > diff --git a/drivers/media/platform/rcar-vin/rcar-csi2.c b/drivers/media/platform/rcar-vin/rcar-csi2.c > index faa9fb2..39e1639 100644 > --- a/drivers/media/platform/rcar-vin/rcar-csi2.c > +++ b/drivers/media/platform/rcar-vin/rcar-csi2.c > @@ -808,6 +808,41 @@ static int rcsi2_parse_v4l2(struct rcar_csi2 *priv, > return 0; > } > > +static bool rcsi2_asd_match(struct device *dev, > + struct v4l2_async_subdev *async_sd) > +{ > + struct rcar_csi2 *priv = (struct rcar_csi2 *) > + async_sd->match.custom.priv; > + struct fwnode_handle *endpoint; > + struct fwnode_handle *remote; > + struct fwnode_handle *parent; > + struct device_node *np; > + bool matched = false; > + > + np = of_graph_get_endpoint_by_regs(priv->dev->of_node, 0, 0); > + if (!np) { > + dev_err(priv->dev, "Not connected to subdevice\n"); > + return -EINVAL; You can't return -EINVAL here as it will be interpreted as a match by the caller ;-). You should not even register a device with v4l2-async if it's not connected to an endpoint. > + } > + > + endpoint = of_fwnode_handle(np); > + remote = fwnode_graph_get_remote_endpoint(endpoint); > + parent = fwnode_graph_get_remote_port_parent(endpoint); > + if (parent) { This is wrong, we will always have a parent and will always take this code path. Hence reducing this to the equivalent of node only matching. I applied this patch and tried on M3-N with a ADv748x and the wrong endpoints of the ADV7482 is routed to the two CSI-2 receivers, breaking it. I added some debug printouts to explain whats going on: * First call dev: rcar-csi2 fea80000.csi2 endpoint: /soc/csi2@feaa0000/ports/port@0/endpoint remote: /soc/i2c@e66d8000/video-receiver@70/port@a/endpoint parent: /soc/i2c@e66d8000/video-receiver@70 dev->fwnode: /soc/csi2@fea80000 dev->of_node: /soc/csi2@fea80000 match: false * Second call dev: adv748x 4-0070 endpoint: /soc/csi2@feaa0000/ports/port@0/endpoint remote: /soc/i2c@e66d8000/video-receiver@70/port@a/endpoint parent: /soc/i2c@e66d8000/video-receiver@70 dev->fwnode: /soc/i2c@e66d8000/video-receiver@70 dev->of_node: /soc/i2c@e66d8000/video-receiver@70 match: true * Third call dev: adv748x 4-0070 endpoint: /soc/csi2@fea80000/ports/port@0/endpoint remote: /soc/i2c@e66d8000/video-receiver@70/port@b/endpoint parent: /soc/i2c@e66d8000/video-receiver@70 dev->fwnode: /soc/i2c@e66d8000/video-receiver@70 dev->of_node: /soc/i2c@e66d8000/video-receiver@70 match: true Now we have a media graph that is completely probed and video devices register in the system but you are not able to stream video as the wrong CSI-2 transmitter is described in the graph to be connected to the wrong receiver. This only strengthens my view that this should not be fixed with a custom matcher in rcar-csi2 but directly in v4l-async. Please see if you can't address the issue in the framework to allow node and endpoint matching to co-exists. > + if (parent == dev->fwnode || > + parent == &dev->of_node->fwnode) > + matched = true; > + } else if (remote && !matched) { No need to check !matched here ;-) > + if (remote == dev->fwnode || > + remote == &dev->of_node->fwnode) > + matched = true; > + } > + > + of_node_put(np); > + > + return matched; > +} > + > static int rcsi2_parse_dt(struct rcar_csi2 *priv) > { > struct device_node *ep; > @@ -833,9 +868,9 @@ static int rcsi2_parse_dt(struct rcar_csi2 *priv) > return ret; > } > > - priv->asd.match.fwnode = > - fwnode_graph_get_remote_endpoint(of_fwnode_handle(ep)); > - priv->asd.match_type = V4L2_ASYNC_MATCH_FWNODE; > + priv->asd.match.custom.match = &rcsi2_asd_match; > + priv->asd.match.custom.priv = priv; > + priv->asd.match_type = V4L2_ASYNC_MATCH_CUSTOM; > > of_node_put(ep); > > -- > 2.7.4 >
Hi Niklas, Thank you for the review. > -----Original Message----- > From: Niklas <niklas.soderlund@ragnatech.se> > Sent: 10 March 2020 12:44 > To: Prabhakar Mahadev Lad <prabhakar.mahadev-lad.rj@bp.renesas.com> > Cc: Mauro Carvalho Chehab <mchehab@kernel.org>; linux- > media@vger.kernel.org; linux-renesas-soc@vger.kernel.org; linux- > kernel@vger.kernel.org; Lad Prabhakar <prabhakar.csengg@gmail.com> > Subject: Re: [PATCH v2 1/3] media: rcar-csi2: Add support to match fwnode > against remote or parent port > > Hi Lad, > > Thanks for your work. > > On 2020-03-10 11:06:02 +0000, Lad Prabhakar wrote: > > The rcar-csi2 driver uses the v4l2-async framework to do endpoint > > matching instead of node matching. This is needed as it needs to work > > with the adv748x driver which register it self in v4l2-async using > > endpoints instead of nodes. The reason for this is that from a single > > DT node it creates multiple subdevices, one for each endpoint. > > > > But when using subdevs which register itself in v4l2-async using > > nodes, the rcar-csi2 driver failed to find the matching endpoint > > because the match.fwnode was pointing to remote endpoint instead of > > remote parent port. > > > > This commit adds support in rcar-csi2 driver to handle both the cases > > where subdev registers in v4l2-async using endpoints/nodes, by using > > match_type as V4L2_ASYNC_MATCH_CUSTOM and implementing the > match() > > callback to compare the fwnode of either remote/parent. > > This is a novel approach to the solution, and I won't object to it out right. But I > think the proper solution is to move this logic into v4l2-async instead of > adding a custom match handler in rcar-csi2. > > Think of the reveres use-case, a different CSI-2 receiver who wish to use the > ADV748x would still have this node vs. endpoint issue. > Agreed. > > > > Signed-off-by: Lad Prabhakar <prabhakar.mahadev- > lad.rj@bp.renesas.com> > > --- > > drivers/media/platform/rcar-vin/rcar-csi2.c | 41 > > ++++++++++++++++++++++++++--- > > 1 file changed, 38 insertions(+), 3 deletions(-) > > > > diff --git a/drivers/media/platform/rcar-vin/rcar-csi2.c > > b/drivers/media/platform/rcar-vin/rcar-csi2.c > > index faa9fb2..39e1639 100644 > > --- a/drivers/media/platform/rcar-vin/rcar-csi2.c > > +++ b/drivers/media/platform/rcar-vin/rcar-csi2.c > > @@ -808,6 +808,41 @@ static int rcsi2_parse_v4l2(struct rcar_csi2 *priv, > > return 0; > > } > > > > +static bool rcsi2_asd_match(struct device *dev, > > + struct v4l2_async_subdev *async_sd) { > > +struct rcar_csi2 *priv = (struct rcar_csi2 *) > > + async_sd->match.custom.priv; > > +struct fwnode_handle *endpoint; > > +struct fwnode_handle *remote; > > +struct fwnode_handle *parent; > > +struct device_node *np; > > +bool matched = false; > > + > > +np = of_graph_get_endpoint_by_regs(priv->dev->of_node, 0, 0); > > +if (!np) { > > +dev_err(priv->dev, "Not connected to subdevice\n"); > > +return -EINVAL; > > You can't return -EINVAL here as it will be interpreted as a match by the caller > ;-). You should not even register a device with v4l2-async if it's not > connected to an endpoint. > My bad. > > +} > > + > > +endpoint = of_fwnode_handle(np); > > +remote = fwnode_graph_get_remote_endpoint(endpoint); > > +parent = fwnode_graph_get_remote_port_parent(endpoint); > > +if (parent) { > > This is wrong, we will always have a parent and will always take this code > path. Hence reducing this to the equivalent of node only matching. > I applied this patch and tried on M3-N with a ADv748x and the wrong > endpoints of the ADV7482 is routed to the two CSI-2 receivers, breaking it. > I did try the media-tree on M3N but it has many issues for booting, could you please point me to a tree which I can use for testing. > I added some debug printouts to explain whats going on: > > * First call > dev: rcar-csi2 fea80000.csi2 > endpoint: /soc/csi2@feaa0000/ports/port@0/endpoint > remote: /soc/i2c@e66d8000/video-receiver@70/port@a/endpoint > parent: /soc/i2c@e66d8000/video-receiver@70 > dev->fwnode: /soc/csi2@fea80000 > dev->of_node: /soc/csi2@fea80000 > match: false > > * Second call > dev: adv748x 4-0070 > endpoint: /soc/csi2@feaa0000/ports/port@0/endpoint > remote: /soc/i2c@e66d8000/video-receiver@70/port@a/endpoint > parent: /soc/i2c@e66d8000/video-receiver@70 > dev->fwnode: /soc/i2c@e66d8000/video-receiver@70 > dev->of_node: /soc/i2c@e66d8000/video-receiver@70 > match: true > > * Third call > dev: adv748x 4-0070 > endpoint: /soc/csi2@fea80000/ports/port@0/endpoint > remote: /soc/i2c@e66d8000/video-receiver@70/port@b/endpoint > parent: /soc/i2c@e66d8000/video-receiver@70 > dev->fwnode: /soc/i2c@e66d8000/video-receiver@70 > dev->of_node: /soc/i2c@e66d8000/video-receiver@70 > match: true > Thank you for the above. > Now we have a media graph that is completely probed and video devices > register in the system but you are not able to stream video as the wrong > CSI-2 transmitter is described in the graph to be connected to the wrong > receiver. > > This only strengthens my view that this should not be fixed with a custom > matcher in rcar-csi2 but directly in v4l-async. Please see if you can't address > the issue in the framework to allow node and endpoint matching to co- > exists. > Ill do some more digging
diff --git a/drivers/media/platform/rcar-vin/rcar-csi2.c b/drivers/media/platform/rcar-vin/rcar-csi2.c index faa9fb2..39e1639 100644 --- a/drivers/media/platform/rcar-vin/rcar-csi2.c +++ b/drivers/media/platform/rcar-vin/rcar-csi2.c @@ -808,6 +808,41 @@ static int rcsi2_parse_v4l2(struct rcar_csi2 *priv, return 0; } +static bool rcsi2_asd_match(struct device *dev, + struct v4l2_async_subdev *async_sd) +{ + struct rcar_csi2 *priv = (struct rcar_csi2 *) + async_sd->match.custom.priv; + struct fwnode_handle *endpoint; + struct fwnode_handle *remote; + struct fwnode_handle *parent; + struct device_node *np; + bool matched = false; + + np = of_graph_get_endpoint_by_regs(priv->dev->of_node, 0, 0); + if (!np) { + dev_err(priv->dev, "Not connected to subdevice\n"); + return -EINVAL; + } + + endpoint = of_fwnode_handle(np); + remote = fwnode_graph_get_remote_endpoint(endpoint); + parent = fwnode_graph_get_remote_port_parent(endpoint); + if (parent) { + if (parent == dev->fwnode || + parent == &dev->of_node->fwnode) + matched = true; + } else if (remote && !matched) { + if (remote == dev->fwnode || + remote == &dev->of_node->fwnode) + matched = true; + } + + of_node_put(np); + + return matched; +} + static int rcsi2_parse_dt(struct rcar_csi2 *priv) { struct device_node *ep; @@ -833,9 +868,9 @@ static int rcsi2_parse_dt(struct rcar_csi2 *priv) return ret; } - priv->asd.match.fwnode = - fwnode_graph_get_remote_endpoint(of_fwnode_handle(ep)); - priv->asd.match_type = V4L2_ASYNC_MATCH_FWNODE; + priv->asd.match.custom.match = &rcsi2_asd_match; + priv->asd.match.custom.priv = priv; + priv->asd.match_type = V4L2_ASYNC_MATCH_CUSTOM; of_node_put(ep);
The rcar-csi2 driver uses the v4l2-async framework to do endpoint matching instead of node matching. This is needed as it needs to work with the adv748x driver which register it self in v4l2-async using endpoints instead of nodes. The reason for this is that from a single DT node it creates multiple subdevices, one for each endpoint. But when using subdevs which register itself in v4l2-async using nodes, the rcar-csi2 driver failed to find the matching endpoint because the match.fwnode was pointing to remote endpoint instead of remote parent port. This commit adds support in rcar-csi2 driver to handle both the cases where subdev registers in v4l2-async using endpoints/nodes, by using match_type as V4L2_ASYNC_MATCH_CUSTOM and implementing the match() callback to compare the fwnode of either remote/parent. Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> --- drivers/media/platform/rcar-vin/rcar-csi2.c | 41 ++++++++++++++++++++++++++--- 1 file changed, 38 insertions(+), 3 deletions(-)