Hi,
begging your pardon for the noob question below...
On 05/03/19 19:51, Jacopo Mondi wrote:
> From: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx>
>
> Add support to get and set the internal routing between the adv748x
> CSI-2 transmitters sink pad and its multiplexed source pad. This routing
> includes which stream of the multiplexed pad to use, allowing the user
> to select which CSI-2 virtual channel to use when transmitting the
> stream.
>
> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx>
> Reviewed-by: Jacopo Mondi <jacopo+renesas@xxxxxxxxxx>
> ---
> drivers/media/i2c/adv748x/adv748x-csi2.c | 65 ++++++++++++++++++++++++
> 1 file changed, 65 insertions(+)
>
> diff --git a/drivers/media/i2c/adv748x/adv748x-csi2.c b/drivers/media/i2c/adv748x/adv748x-csi2.c
> index d8f7cbee86e7..13454af72c6e 100644
> --- a/drivers/media/i2c/adv748x/adv748x-csi2.c
> +++ b/drivers/media/i2c/adv748x/adv748x-csi2.c
> @@ -14,6 +14,8 @@
>
> #include "adv748x.h"
>
> +#define ADV748X_CSI2_ROUTES_MAX 4
> +
> struct adv748x_csi2_format {
> unsigned int code;
> unsigned int datatype;
> @@ -253,10 +255,73 @@ static int adv748x_csi2_get_frame_desc(struct v4l2_subdev *sd, unsigned int pad,
> return 0;
> }
>
> +static int adv748x_csi2_get_routing(struct v4l2_subdev *sd,
> + struct v4l2_subdev_krouting *routing)
> +{
> + struct adv748x_csi2 *tx = adv748x_sd_to_csi2(sd);
> + struct v4l2_subdev_route *r = routing->routes;
> + unsigned int vc;
> +
> + if (routing->num_routes < ADV748X_CSI2_ROUTES_MAX) {
> + routing->num_routes = ADV748X_CSI2_ROUTES_MAX;
> + return -ENOSPC;
> + }
> +
> + routing->num_routes = ADV748X_CSI2_ROUTES_MAX;
> +
> + for (vc = 0; vc < ADV748X_CSI2_ROUTES_MAX; vc++) {
> + r->sink_pad = ADV748X_CSI2_SINK;
> + r->sink_stream = 0;
> + r->source_pad = ADV748X_CSI2_SOURCE;
> + r->source_stream = vc;
> + r->flags = vc == tx->vc ? V4L2_SUBDEV_ROUTE_FL_ACTIVE : 0;
> + r++;Begging your pardon for the noob question...
> + }
> +
> + return 0;
> +}
> +
> +static int adv748x_csi2_set_routing(struct v4l2_subdev *sd,
> + struct v4l2_subdev_krouting *routing)
> +{
> + struct adv748x_csi2 *tx = adv748x_sd_to_csi2(sd);
> + struct v4l2_subdev_route *r = routing->routes;
> + unsigned int i;
> + int vc = -1;
> +
> + if (routing->num_routes > ADV748X_CSI2_ROUTES_MAX)
> + return -ENOSPC;
> +
> + for (i = 0; i < routing->num_routes; i++) {
> + if (r->sink_pad != ADV748X_CSI2_SINK ||
> + r->sink_stream != 0 ||
> + r->source_pad != ADV748X_CSI2_SOURCE ||
> + r->source_stream >= ADV748X_CSI2_ROUTES_MAX)
> + return -EINVAL;
> +
> + if (r->flags & V4L2_SUBDEV_ROUTE_FL_ACTIVE) {
> + if (vc != -1)
> + return -EMLINK;
> +
> + vc = r->source_stream;
> + }
> + r++;
> + }
> +
> + if (vc != -1)
> + tx->vc = vc;
> +
> + adv748x_csi2_set_virtual_channel(tx, tx->vc);
> +
> + return 0;
> +}
Not specific to this patch but rather to the set_routing idea as a
whole: can the set_routing ioctl be called while the stream is running?
If it cannot, I find it a limiting factor for nowadays use cases. I also
didn't find where the ioctl is rejected.
If it can, then shouldn't this function call s_stream(stop) through the
sink pad whose route becomes disabled, and a s_stream(start) through the
one that gets enabled?
Thanks,
--
Luca
