Hi Tomi,
On 10/3/22 14:18, 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 | 87 +++++++++++++++++++++++++++
> include/media/v4l2-subdev.h | 22 +++++++
> include/uapi/linux/v4l2-subdev.h | 52 ++++++++++++++++
> 4 files changed, 185 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
> index fddba75d9074..26b9a9626c96 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/media-device.h> /* for media_set_bus_info() */
> @@ -3151,6 +3152,21 @@ 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 -E2BIG;
> +
> + *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;
> @@ -3397,8 +3413,15 @@ 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;
>
> if (has_array_args) {
> diff --git a/drivers/media/v4l2-core/v4l2-subdev.c b/drivers/media/v4l2-core/v4l2-subdev.c
> index 8983d33fdb4b..1a451351554b 100644
> --- a/drivers/media/v4l2-core/v4l2-subdev.c
> +++ b/drivers/media/v4l2-core/v4l2-subdev.c
> @@ -23,6 +23,16 @@
> #include <media/v4l2-fh.h>
> #include <media/v4l2-ioctl.h>
>
> +/*
> + * Maximum stream ID is 63 for now, as we use u64 bitmask to represent a set
> + * of streams.
> + *
> + * Note that V4L2_FRAME_DESC_ENTRY_MAX is related: V4L2_FRAME_DESC_ENTRY_MAX
> + * restricts the total number of streams in a pad, although the stream ID is
> + * not restricted.
> + */
> +#define V4L2_SUBDEV_MAX_STREAM_ID 63
> +
> #if defined(CONFIG_VIDEO_V4L2_SUBDEV_API)
> static int subdev_fh_init(struct v4l2_subdev_fh *fh, struct v4l2_subdev *sd)
> {
> @@ -417,6 +427,10 @@ subdev_ioctl_get_state(struct v4l2_subdev *sd, struct v4l2_subdev_fh *subdev_fh,
> case VIDIOC_SUBDEV_S_SELECTION:
> 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 ?
> @@ -733,6 +747,78 @@ 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_STREAMS))
> + 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_STREAMS))
> + 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;
> +
> + if (route->sink_stream > V4L2_SUBDEV_MAX_STREAM_ID ||
> + route->source_stream > V4L2_SUBDEV_MAX_STREAM_ID)
> + return -EINVAL;
> +
> + /* 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.num_routes = routing->num_routes;
> + krouting.routes = routes;
> +
> + return v4l2_subdev_call(sd, pad, set_routing, state,
> + routing->which, &krouting);
> + }
> +
> default:
> return v4l2_subdev_call(sd, core, ioctl, cmd, arg);
> }
> @@ -1016,6 +1102,7 @@ void __v4l2_subdev_state_free(struct v4l2_subdev_state *state)
>
> mutex_destroy(&state->_lock);
>
> + kfree(state->routing.routes);
> kvfree(state->pads);
> kfree(state);
> }
> diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
> index 4be0a590c7c7..4934dc9468a8 100644
> --- a/include/media/v4l2-subdev.h
> +++ b/include/media/v4l2-subdev.h
> @@ -695,12 +695,26 @@ struct v4l2_subdev_pad_config {
> struct v4l2_rect try_compose;
> };
>
> +/**
> + * struct v4l2_subdev_krouting - subdev routing table
> + *
> + * @num_routes: number of routes
> + * @routes: &struct v4l2_subdev_route
> + *
> + * This structure contains the routing table for a subdev.
> + */
> +struct v4l2_subdev_krouting {
> + unsigned int num_routes;
> + struct v4l2_subdev_route *routes;
> +};
> +
> /**
> * struct v4l2_subdev_state - Used for storing subdev state information.
> *
> * @_lock: default for 'lock'
> * @lock: mutex for the state. May be replaced by the user.
> * @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
> @@ -711,6 +725,7 @@ struct v4l2_subdev_state {
> struct mutex _lock;
> struct mutex *lock;
> struct v4l2_subdev_pad_config *pads;
> + struct v4l2_subdev_krouting routing;
> };
>
> /**
> @@ -763,6 +778,9 @@ struct v4l2_subdev_state {
> * this operation as close as possible to stream on time. 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,
> @@ -805,6 +823,10 @@ struct v4l2_subdev_pad_ops {
> struct v4l2_mbus_frame_desc *fd);
> int (*get_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,
> + enum v4l2_subdev_format_whence which,
> + struct v4l2_subdev_krouting *route);
> };
>
> /**
> diff --git a/include/uapi/linux/v4l2-subdev.h b/include/uapi/linux/v4l2-subdev.h
> index 89af27f50a41..db4af236d7ed 100644
> --- a/include/uapi/linux/v4l2-subdev.h
> +++ b/include/uapi/linux/v4l2-subdev.h
> @@ -24,6 +24,7 @@
> #ifndef __LINUX_V4L2_SUBDEV_H
> #define __LINUX_V4L2_SUBDEV_H
>
> +#include <linux/const.h>
> #include <linux/ioctl.h>
> #include <linux/types.h>
> #include <linux/v4l2-common.h>
> @@ -191,6 +192,55 @@ struct v4l2_subdev_capability {
> /* The v4l2 sub-device supports routing and multiplexed streams. */
> #define V4L2_SUBDEV_CAP_STREAMS 0x00000002
>
> +/*
> + * Is the route active? An active route will start when streaming is enabled
> + * on a video node.
> + */
> +#define V4L2_SUBDEV_ROUTE_FL_ACTIVE (1U << 0)
> +
> +/*
> + * Is the route a source endpoint? A source endpoint route refers to a stream
> + * generated 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 (1U << 1)
Can we rename this to _FL_INTERNAL_SOURCE? Just 'SOURCE' is very confusing
IMHO. The name 'INTERNAL_SOURCE' makes it clear that it is generated internally,
and so does not come from an external sink-side endpoint.
I also think that the documentation for this flag in patch 04/19 is very vague,
I'll comment on that patch as well.
Regards,
Hans
> +
> +/**
> + * 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)
> + * @num_routes: the total number of routes in the routes array
> + * @routes: pointer to the routes array
> + * @reserved: drivers and applications must zero this array
> + */
> +struct v4l2_subdev_routing {
> + __u32 which;
> + __u32 num_routes;
> + __u64 routes;
> + __u32 reserved[6];
> +};
> +
> /* Backwards compatibility define --- to be removed */
> #define v4l2_subdev_edid v4l2_edid
>
> @@ -206,6 +256,8 @@ 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)
