Hi Sakari, Laurent, Niklas, (another) quick question, but a different one :) On Wed, Jan 16, 2019 at 01:51:45AM +0200, Laurent Pinchart wrote: > Hi Niklas, > > Thank you for the patch. > > On Fri, Nov 02, 2018 at 12:31:30AM +0100, Niklas Söderlund wrote: > > From: Laurent Pinchart > > > > Signed-off-by: Laurent Pinchart > > Signed-off-by: Michal Simek > > > > - 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 > > Reviewed-by: Niklas Söderlund > > --- > > 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 +++++++++++++++++++++++++++ > > Missing documentation :-( > > > 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 > > #include > > > > +#include > > #include > > > > #include > > @@ -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) > > This seems like a hack. Shouldn't VIDIOC_SUBDEV_G_ROUTING set > always_copy instead ? > > > 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) { How have you envisioned the number of routes to be negotiated with applications? I'm writing the documentation for this ioctl, and I would like to insert this part as well. Would a model like the one implemented in G_TOPOLOGY work in your opinion? In my understanding, at the moment applications do not have a way to reserve a known number of routes entries, but would likely reserve 'enough(tm)' (ie 256) and pass them to the G_ROUTING ioctl that the first time will likely adjust the number of num_routes and return -ENOSPC. Wouldn't it work to make the IOCTL behave in a way that it expects the first call to be performed with (num_routes == 0) and no routes entries reserved, and just adjust 'num_routes' in that case? So that applications should call G_ROUTING a first time with num_routes = 0, get back the number of routes entries, reserve memory for them, and then call G_ROUTING again to have the entries populated by the driver. Do you have different ideas or was this the intended behavior already? Thanks j > > + 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. > > Please define the purpose of those operations instead of just pointing > to the userspace API. > > > */ > > 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 > > At this point in the series there's no concept of multiplexed streams, > so the two fields don't make sense. You may want to reorder patches, or > split this in two. > > > + * @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. > > This is very confusing as "stream" isn't defined. The documentation > needs a rewrite with more details. > > > + * > > + * 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; > > Missing __user ? > > > + __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 > > > > -- > Regards, > > Laurent Pinchart