Hi Tomi,
On Mon, Aug 30, 2021 at 02:01:08PM +0300, Tomi Valkeinen wrote:
> From: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
>
> Add support for subdev internal routing. A route is defined as a single
> stream from a sink pad to a source pad.
>
> The userspace can configure the routing via two new ioctls,
> VIDIOC_SUBDEV_G_ROUTING and VIDIOC_SUBDEV_S_ROUTING, and subdevs can
> implement the functionality with v4l2_subdev_pad_ops.set_routing().
>
> Signed-off-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> Signed-off-by: Michal Simek <michal.simek@xxxxxxxxxx>
>
> - 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@xxxxxxxxxxxxxxx>
>
> - Expand and refine documentation.
> - Make the 'routes' pointer a __u64 __user pointer so that a compat32
> version of the ioctl is not required.
> - Add struct v4l2_subdev_krouting to be used for subdevice operations.
>
> Signed-off-by: Jacopo Mondi <jacopo+renesas@xxxxxxxxxx>
>
> - Fix typecasing warnings
> - Check sink & source pad types
> - Add 'which' field
> - Add V4L2_SUBDEV_ROUTE_FL_SOURCE
> - Routing to subdev state
> - Dropped get_routing subdev op
>
> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@xxxxxxxxxxxxxxxx>
> ---
> drivers/media/v4l2-core/v4l2-ioctl.c | 25 ++++++++-
> drivers/media/v4l2-core/v4l2-subdev.c | 75 +++++++++++++++++++++++++++
> include/media/v4l2-subdev.h | 24 +++++++++
> include/uapi/linux/v4l2-subdev.h | 57 ++++++++++++++++++++
> 4 files changed, 180 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
> index 05d5db3d85e5..8e9315ffcb99 100644
> --- a/drivers/media/v4l2-core/v4l2-ioctl.c
> +++ b/drivers/media/v4l2-core/v4l2-ioctl.c
> @@ -16,6 +16,7 @@
> #include <linux/kernel.h>
> #include <linux/version.h>
>
> +#include <linux/v4l2-subdev.h>
> #include <linux/videodev2.h>
>
> #include <media/v4l2-common.h>
> @@ -3065,6 +3066,21 @@ static int check_array_args(unsigned int cmd, void *parg, size_t *array_size,
> ret = 1;
> break;
> }
> +
> + case VIDIOC_SUBDEV_G_ROUTING:
> + case VIDIOC_SUBDEV_S_ROUTING: {
> + struct v4l2_subdev_routing *routing = parg;
> +
> + if (routing->num_routes > 256)
> + return -EINVAL;
> +
> + *user_ptr = u64_to_user_ptr(routing->routes);
> + *kernel_ptr = (void **)&routing->routes;
> + *array_size = sizeof(struct v4l2_subdev_route)
> + * routing->num_routes;
> + ret = 1;
> + break;
> + }
> }
>
> return ret;
> @@ -3328,8 +3344,15 @@ video_usercopy(struct file *file, unsigned int orig_cmd, unsigned long arg,
> /*
> * Some ioctls can return an error, but still have valid
> * results that must be returned.
> + *
> + * FIXME: subdev IOCTLS are partially handled here and partially in
> + * v4l2-subdev.c and the 'always_copy' flag can only be set for IOCTLS
> + * defined here as part of the 'v4l2_ioctls' array. As
> + * VIDIOC_SUBDEV_G_ROUTING needs to return results to applications even
> + * in case of failure, but it is not defined here as part of the
> + * 'v4l2_ioctls' array, insert an ad-hoc check to address that.
> */
> - 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 b1e65488210d..0e1f325b3159 100644
> --- a/drivers/media/v4l2-core/v4l2-subdev.c
> +++ b/drivers/media/v4l2-core/v4l2-subdev.c
> @@ -395,6 +395,12 @@ subdev_ioctl_get_state(struct v4l2_subdev *sd, struct v4l2_subdev_fh *subdev_fh,
> which = ((struct v4l2_subdev_selection *)arg)->which;
> break;
> }
> +
> + case VIDIOC_SUBDEV_G_ROUTING:
> + case VIDIOC_SUBDEV_S_ROUTING: {
> + which = ((struct v4l2_subdev_routing *)arg)->which;
> + break;
> + }
> }
>
> return which == V4L2_SUBDEV_FORMAT_TRY ?
> @@ -711,6 +717,74 @@ 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: {
> + struct v4l2_subdev_routing *routing = arg;
> + struct v4l2_subdev_krouting *krouting;
> +
> + if (!(sd->flags & V4L2_SUBDEV_FL_MULTIPLEXED))
> + return -ENOIOCTLCMD;
> +
> + memset(routing->reserved, 0, sizeof(routing->reserved));
> +
> + krouting = &state->routing;
> +
> + if (routing->num_routes < krouting->num_routes) {
> + routing->num_routes = krouting->num_routes;
> + return -ENOSPC;
> + }
> +
> + memcpy((struct v4l2_subdev_route *)(uintptr_t)routing->routes,
> + krouting->routes,
> + krouting->num_routes * sizeof(*krouting->routes));
> + routing->num_routes = krouting->num_routes;
> +
> + return 0;
> + }
> +
> + case VIDIOC_SUBDEV_S_ROUTING: {
> + struct v4l2_subdev_routing *routing = arg;
> + struct v4l2_subdev_route *routes =
> + (struct v4l2_subdev_route *)(uintptr_t)routing->routes;
> + struct v4l2_subdev_krouting krouting = {};
> + unsigned int i;
> +
> + if (!(sd->flags & V4L2_SUBDEV_FL_MULTIPLEXED))
> + return -ENOIOCTLCMD;
> +
> + if (routing->which != V4L2_SUBDEV_FORMAT_TRY && ro_subdev)
> + return -EPERM;
> +
> + memset(routing->reserved, 0, sizeof(routing->reserved));
> +
> + for (i = 0; i < routing->num_routes; ++i) {
> + const struct v4l2_subdev_route *route = &routes[i];
> + const struct media_pad *pads = sd->entity.pads;
> +
> + /* Do not check sink pad for source routes */
> + if (!(route->flags & V4L2_SUBDEV_ROUTE_FL_SOURCE)) {
> + if (route->sink_pad >= sd->entity.num_pads)
> + return -EINVAL;
> +
> + if (!(pads[route->sink_pad].flags &
> + MEDIA_PAD_FL_SINK))
> + return -EINVAL;
> + }
> +
> + if (route->source_pad >= sd->entity.num_pads)
> + return -EINVAL;
> +
> + if (!(pads[route->source_pad].flags &
> + MEDIA_PAD_FL_SOURCE))
> + return -EINVAL;
> + }
> +
> + krouting.which = routing->which;
> + krouting.num_routes = routing->num_routes;
> + krouting.routes = routes;
> +
> + return v4l2_subdev_call(sd, pad, set_routing, state, &krouting);
> + }
> +
> default:
> return v4l2_subdev_call(sd, core, ioctl, cmd, arg);
> }
> @@ -975,6 +1049,7 @@ void v4l2_free_subdev_state(struct v4l2_subdev_state *state)
>
> mutex_destroy(&state->lock);
>
> + kvfree(state->routing.routes);
> kvfree(state->pads);
> kfree(state);
> }
> diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
> index 356901d8a948..cd6aad21ae0c 100644
> --- a/include/media/v4l2-subdev.h
> +++ b/include/media/v4l2-subdev.h
> @@ -694,12 +694,29 @@ struct v4l2_subdev_pad_config {
> struct v4l2_rect try_compose;
> };
>
> +/**
> + * struct v4l2_subdev_krouting - subdev routing table
> + *
> + * @which: format type (from enum v4l2_subdev_format_whence)
> + * @routes: &struct v4l2_subdev_route
> + * @num_routes: number of routes
> + *
> + * This structure is used to translate arguments received from
> + * VIDIOC_SUBDEV_G/S_ROUTING() ioctl to subdev device drivers operations.
> + */
> +struct v4l2_subdev_krouting {
> + u32 which;
> + struct v4l2_subdev_route *routes;
> + unsigned int num_routes;
> +};
> +
> /**
> * struct v4l2_subdev_state - Used for storing subdev state information.
> *
> * @lock: mutex for the state
> * @which: state type (from enum v4l2_subdev_format_whence)
> * @pads: &struct v4l2_subdev_pad_config array
> + * @routing: routing table for the subdev
> *
> * This structure only needs to be passed to the pad op if the 'which' field
> * of the main argument is set to %V4L2_SUBDEV_FORMAT_TRY. For
> @@ -709,6 +726,7 @@ struct v4l2_subdev_state {
> struct mutex lock;
> u32 which;
> struct v4l2_subdev_pad_config *pads;
> + struct v4l2_subdev_krouting routing;
> };
>
> /**
> @@ -772,6 +790,9 @@ struct v4l2_subdev_state {
> * applied to the hardware. The operation shall fail if the
> * pad index it has been called on is not valid or in case of
> * unrecoverable failures.
> + *
> + * @set_routing: enable or disable data connection routes described in the
> + * subdevice routing table.
> */
> struct v4l2_subdev_pad_ops {
> int (*init_cfg)(struct v4l2_subdev *sd,
> @@ -816,6 +837,9 @@ struct v4l2_subdev_pad_ops {
> struct v4l2_mbus_config *config);
> int (*set_mbus_config)(struct v4l2_subdev *sd, unsigned int pad,
> struct v4l2_mbus_config *config);
> + int (*set_routing)(struct v4l2_subdev *sd,
> + struct v4l2_subdev_state *state,
> + struct v4l2_subdev_krouting *route);
> };
>
> /**
> diff --git a/include/uapi/linux/v4l2-subdev.h b/include/uapi/linux/v4l2-subdev.h
> index 658106f5b5dc..3aa623e0e5f9 100644
> --- a/include/uapi/linux/v4l2-subdev.h
> +++ b/include/uapi/linux/v4l2-subdev.h
> @@ -188,6 +188,61 @@ struct v4l2_subdev_capability {
> /* The v4l2 sub-device video device node is registered in read-only mode. */
> #define V4L2_SUBDEV_CAP_RO_SUBDEV 0x00000001
>
> +/*
> + * Is the route active? An active route will start when streaming is enabled
> + * on a video node.
> + */
> +#define V4L2_SUBDEV_ROUTE_FL_ACTIVE BIT(0)
Am I wrong or BIT() is not available to userspace ?
../../include/linux/v4l2-subdev.h:209:38: error: ‘BIT’ was not declared in this scope
209 | #define V4L2_SUBDEV_ROUTE_FL_ACTIVE BIT(0)
Header was exported with headers_install.
> +
> +/*
> + * Is the route immutable, i.e. can it be activated and inactivated?
> + * Set by the driver.
> + */
> +#define V4L2_SUBDEV_ROUTE_FL_IMMUTABLE BIT(1)
> +
> +/*
> + * Is the route a source endpoint? A source endpoint route refers to a stream
> + * generated internally by the subdevice (usually a sensor), and thus there
> + * is no sink-side endpoint for the route. The sink_pad and sink_stream
> + * fields are unused.
> + * Set by the driver.
> + */
> +#define V4L2_SUBDEV_ROUTE_FL_SOURCE BIT(2)
> +
> +/**
> + * struct v4l2_subdev_route - A route inside a subdev
> + *
> + * @sink_pad: the sink pad index
> + * @sink_stream: the sink stream identifier
> + * @source_pad: the source pad index
> + * @source_stream: the source stream identifier
> + * @flags: route flags V4L2_SUBDEV_ROUTE_FL_*
> + * @reserved: drivers and applications must zero this array
> + */
> +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 - Subdev routing information
> + *
> + * @which: configuration type (from enum v4l2_subdev_format_whence)
> + * @routes: pointer to the routes array
> + * @num_routes: the total number of routes in the routes array
> + * @reserved: drivers and applications must zero this array
> + */
> +struct v4l2_subdev_routing {
> + __u32 which;
> + __u64 routes;
> + __u32 num_routes;
> + __u32 reserved[5];
> +};
> +
> /* Backwards compatibility define --- to be removed */
> #define v4l2_subdev_edid v4l2_edid
>
> @@ -203,6 +258,8 @@ struct v4l2_subdev_capability {
> #define VIDIOC_SUBDEV_S_CROP _IOWR('V', 60, struct v4l2_subdev_crop)
> #define VIDIOC_SUBDEV_G_SELECTION _IOWR('V', 61, struct v4l2_subdev_selection)
> #define VIDIOC_SUBDEV_S_SELECTION _IOWR('V', 62, struct v4l2_subdev_selection)
> +#define VIDIOC_SUBDEV_G_ROUTING _IOWR('V', 38, struct v4l2_subdev_routing)
> +#define VIDIOC_SUBDEV_S_ROUTING _IOWR('V', 39, struct v4l2_subdev_routing)
> /* The following ioctls are identical to the ioctls in videodev2.h */
> #define VIDIOC_SUBDEV_G_STD _IOR('V', 23, v4l2_std_id)
> #define VIDIOC_SUBDEV_S_STD _IOW('V', 24, v4l2_std_id)
> --
> 2.25.1
>
