[PATCH v2 16/30] v4l: subdev: Add [GS]_ROUTING subdev ioctls and operations

["Niklas Söderlund" <niklas.soderlund+renesas@ragnatech.se>]

From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>

- Add sink and source streams for multiplexed links
- Copy the argument back in case of an error. This is needed to let the
  caller know the number of routes.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
---
 drivers/media/v4l2-core/v4l2-ioctl.c  | 20 +++++++++++++-
 drivers/media/v4l2-core/v4l2-subdev.c | 28 +++++++++++++++++++
 include/media/v4l2-subdev.h           |  7 +++++
 include/uapi/linux/v4l2-subdev.h      | 40 +++++++++++++++++++++++++++
 4 files changed, 94 insertions(+), 1 deletion(-)

diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
index 7de041bae84fb2f2..40406acb51ec0906 100644
--- a/drivers/media/v4l2-core/v4l2-ioctl.c
+++ b/drivers/media/v4l2-core/v4l2-ioctl.c
@@ -19,6 +19,7 @@
 #include <linux/kernel.h>
 #include <linux/version.h>
 
+#include <linux/v4l2-subdev.h>
 #include <linux/videodev2.h>
 
 #include <media/v4l2-common.h>
@@ -2924,6 +2925,23 @@ static int check_array_args(unsigned int cmd, void *parg, size_t *array_size,
 		}
 		break;
 	}
+
+	case VIDIOC_SUBDEV_G_ROUTING:
+	case VIDIOC_SUBDEV_S_ROUTING: {
+		struct v4l2_subdev_routing *route = parg;
+
+		if (route->num_routes > 0) {
+			if (route->num_routes > 256)
+				return -EINVAL;
+
+			*user_ptr = (void __user *)route->routes;
+			*kernel_ptr = (void *)&route->routes;
+			*array_size = sizeof(struct v4l2_subdev_route)
+				    * route->num_routes;
+			ret = 1;
+		}
+		break;
+	}
 	}
 
 	return ret;
@@ -3033,7 +3051,7 @@ video_usercopy(struct file *file, unsigned int cmd, unsigned long arg,
 	 * Some ioctls can return an error, but still have valid
 	 * results that must be returned.
 	 */
-	if (err < 0 && !always_copy)
+	if (err < 0 && !always_copy && cmd != VIDIOC_SUBDEV_G_ROUTING)
 		goto out;
 
 out_array_args:
diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c
index 792f41dffe2329b9..1d3b37cf548fa533 100644
--- a/drivers/media/v4l2-core/v4l2-subdev.c
+++ b/drivers/media/v4l2-core/v4l2-subdev.c
@@ -516,7 +516,35 @@ static long subdev_do_ioctl(struct file *file, unsigned int cmd, void *arg)
 
 	case VIDIOC_SUBDEV_QUERYSTD:
 		return v4l2_subdev_call(sd, video, querystd, arg);
+
+	case VIDIOC_SUBDEV_G_ROUTING:
+		return v4l2_subdev_call(sd, pad, get_routing, arg);
+
+	case VIDIOC_SUBDEV_S_ROUTING: {
+		struct v4l2_subdev_routing *route = arg;
+		unsigned int i;
+
+		if (route->num_routes > sd->entity.num_pads)
+			return -EINVAL;
+
+		for (i = 0; i < route->num_routes; ++i) {
+			unsigned int sink = route->routes[i].sink_pad;
+			unsigned int source = route->routes[i].source_pad;
+			struct media_pad *pads = sd->entity.pads;
+
+			if (sink >= sd->entity.num_pads ||
+			    source >= sd->entity.num_pads)
+				return -EINVAL;
+
+			if (!(pads[sink].flags & MEDIA_PAD_FL_SINK) ||
+			    !(pads[source].flags & MEDIA_PAD_FL_SOURCE))
+				return -EINVAL;
+		}
+
+		return v4l2_subdev_call(sd, pad, set_routing, route);
+	}
 #endif
+
 	default:
 		return v4l2_subdev_call(sd, core, ioctl, cmd, arg);
 	}
diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
index 9102d6ca566e01f2..5acaeeb9b3cacefa 100644
--- a/include/media/v4l2-subdev.h
+++ b/include/media/v4l2-subdev.h
@@ -679,6 +679,9 @@ struct v4l2_subdev_pad_config {
  *
  * @set_frame_desc: set the low level media bus frame parameters, @fd array
  *                  may be adjusted by the subdev driver to device capabilities.
+ *
+ * @get_routing: callback for VIDIOC_SUBDEV_G_ROUTING IOCTL handler.
+ * @set_routing: callback for VIDIOC_SUBDEV_S_ROUTING IOCTL handler.
  */
 struct v4l2_subdev_pad_ops {
 	int (*init_cfg)(struct v4l2_subdev *sd,
@@ -719,6 +722,10 @@ struct v4l2_subdev_pad_ops {
 			      struct v4l2_mbus_frame_desc *fd);
 	int (*set_frame_desc)(struct v4l2_subdev *sd, unsigned int pad,
 			      struct v4l2_mbus_frame_desc *fd);
+	int (*get_routing)(struct v4l2_subdev *sd,
+			   struct v4l2_subdev_routing *route);
+	int (*set_routing)(struct v4l2_subdev *sd,
+			   struct v4l2_subdev_routing *route);
 };
 
 /**
diff --git a/include/uapi/linux/v4l2-subdev.h b/include/uapi/linux/v4l2-subdev.h
index 03970ce3074193e6..af069bfb10ca23a5 100644
--- a/include/uapi/linux/v4l2-subdev.h
+++ b/include/uapi/linux/v4l2-subdev.h
@@ -155,6 +155,44 @@ struct v4l2_subdev_selection {
 	__u32 reserved[8];
 };
 
+#define V4L2_SUBDEV_ROUTE_FL_ACTIVE	(1 << 0)
+#define V4L2_SUBDEV_ROUTE_FL_IMMUTABLE	(1 << 1)
+
+/**
+ * struct v4l2_subdev_route - A signal route inside a subdev
+ * @sink_pad: the sink pad
+ * @sink_stream: the sink stream
+ * @source_pad: the source pad
+ * @source_stream: the source stream
+ * @flags: route flags:
+ *
+ *	V4L2_SUBDEV_ROUTE_FL_ACTIVE: Is the stream in use or not? An
+ *	active stream will start when streaming is enabled on a video
+ *	node. Set by the user.
+ *
+ *	V4L2_SUBDEV_ROUTE_FL_IMMUTABLE: Is the stream immutable, i.e.
+ *	can it be activated and inactivated? Set by the driver.
+ */
+struct v4l2_subdev_route {
+	__u32 sink_pad;
+	__u32 sink_stream;
+	__u32 source_pad;
+	__u32 source_stream;
+	__u32 flags;
+	__u32 reserved[5];
+};
+
+/**
+ * struct v4l2_subdev_routing - Routing information
+ * @routes: the routes array
+ * @num_routes: the total number of routes in the routes array
+ */
+struct v4l2_subdev_routing {
+	struct v4l2_subdev_route *routes;
+	__u32 num_routes;
+	__u32 reserved[5];
+};
+
 /* Backwards compatibility define --- to be removed */
 #define v4l2_subdev_edid v4l2_edid
 
@@ -181,5 +219,7 @@ struct v4l2_subdev_selection {
 #define VIDIOC_SUBDEV_ENUM_DV_TIMINGS		_IOWR('V', 98, struct v4l2_enum_dv_timings)
 #define VIDIOC_SUBDEV_QUERY_DV_TIMINGS		_IOR('V', 99, struct v4l2_dv_timings)
 #define VIDIOC_SUBDEV_DV_TIMINGS_CAP		_IOWR('V', 100, struct v4l2_dv_timings_cap)
+#define VIDIOC_SUBDEV_G_ROUTING			_IOWR('V', 38, struct v4l2_subdev_routing)
+#define VIDIOC_SUBDEV_S_ROUTING			_IOWR('V', 39, struct v4l2_subdev_routing)
 
 #endif
-- 
2.19.1