On Thu, Dec 14, 2017 at 08:08:25PM +0100, Niklas Söderlund wrote:
> The R-Car CSI-2 hardware can output the same virtual channel
> simultaneously to more then one R-Car VIN. For this reason we need to
> move the usage counting from the global device to each source pad.
>
> If a source pads usage count go from 0 to 1 we need to signal that a new
> stream should start, likewise if it go from 1 to 0 we need to stop a
> stream. At the same time we only want to start or stop the R-Car
> CSI-2 device only on the first or last stream.
>
> Signed-off-by: Niklas Söderlund <[email protected]>
> ---
> drivers/media/platform/rcar-vin/rcar-csi2.c | 38
> +++++++++++++++++++++++------
> 1 file changed, 30 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/media/platform/rcar-vin/rcar-csi2.c
> b/drivers/media/platform/rcar-vin/rcar-csi2.c
> index 8ce0bfeef1113f9c..e0f56cc3d25179a9 100644
> --- a/drivers/media/platform/rcar-vin/rcar-csi2.c
> +++ b/drivers/media/platform/rcar-vin/rcar-csi2.c
> @@ -328,6 +328,14 @@ enum rcar_csi2_pads {
> NR_OF_RCAR_CSI2_PAD,
> };
>
> +static int rcar_csi2_pad_to_vc(unsigned int pad)
> +{
> + if (pad < RCAR_CSI2_SOURCE_VC0 || pad > RCAR_CSI2_SOURCE_VC3)
> + return -EINVAL;
> +
> + return pad - RCAR_CSI2_SOURCE_VC0;
> +}
> +
> struct rcar_csi2_info {
> const struct phypll_hsfreqrange *hsfreqrange;
> const struct phtw_testdin_data *testdin_data;
> @@ -350,7 +358,7 @@ struct rcar_csi2 {
> struct v4l2_mbus_framefmt mf;
>
> struct mutex lock;
> - int stream_count;
> + int stream_count[4];
Why 4?
>
> unsigned short lanes;
> unsigned char lane_swap[4];
> @@ -630,7 +638,13 @@ static int rcar_csi2_s_stream(struct v4l2_subdev *sd,
> unsigned int pad,
> {
> struct rcar_csi2 *priv = sd_to_csi2(sd);
> struct v4l2_subdev *nextsd;
> - int ret;
> + unsigned int i, count = 0;
> + int ret, vc;
> +
> + /* Only allow stream control on source pads and valid vc */
> + vc = rcar_csi2_pad_to_vc(pad);
> + if (vc < 0)
> + return vc;
>
> /* Only one stream on each source pad */
> if (stream != 0)
> @@ -642,7 +656,10 @@ static int rcar_csi2_s_stream(struct v4l2_subdev *sd,
> unsigned int pad,
> if (ret)
> goto out;
>
> - if (enable && priv->stream_count == 0) {
> + for (i = 0; i < 4; i++)
> + count += priv->stream_count[i];
> +
> + if (enable && count == 0) {
> pm_runtime_get_sync(priv->dev);
>
> ret = rcar_csi2_start(priv);
> @@ -650,20 +667,23 @@ static int rcar_csi2_s_stream(struct v4l2_subdev *sd,
> unsigned int pad,
> pm_runtime_put(priv->dev);
> goto out;
> }
> + } else if (!enable && count == 1) {
> + rcar_csi2_stop(priv);
> + pm_runtime_put(priv->dev);
> + }
>
> + if (enable && priv->stream_count[vc] == 0) {
> ret = v4l2_subdev_call(nextsd, video, s_stream, 1);
> if (ret) {
> rcar_csi2_stop(priv);
> pm_runtime_put(priv->dev);
> goto out;
> }
> - } else if (!enable && priv->stream_count == 1) {
> - rcar_csi2_stop(priv);
> + } else if (!enable && priv->stream_count[vc] == 1) {
Do I understand correctly that you can start and streams here one by one,
independently of each other?
Sometimes this might not be the case. I wonder if we should have a way to
tell that to the caller.
> ret = v4l2_subdev_call(nextsd, video, s_stream, 0);
> - pm_runtime_put(priv->dev);
> }
>
> - priv->stream_count += enable ? 1 : -1;
> + priv->stream_count[vc] += enable ? 1 : -1;
> out:
> mutex_unlock(&priv->lock);
>
> @@ -919,7 +939,9 @@ static int rcar_csi2_probe(struct platform_device *pdev)
> priv->dev = &pdev->dev;
>
> mutex_init(&priv->lock);
> - priv->stream_count = 0;
> +
> + for (i = 0; i < 4; i++)
> + priv->stream_count[i] = 0;
>
> ret = rcar_csi2_probe_resources(priv, pdev);
> if (ret) {
> --
> 2.15.1
>
--
Sakari Ailus
[email protected]
