media: vimc: Add vimc-streamer for stream control

Add a linear pipeline logic for the stream control. It's created by
walking backwards on the entity graph. When the stream starts it will
simply loop through the pipeline calling the respective process_frame
function of each entity.

Fixes: f2fe89061d797 ("vimc: Virtual Media Controller core, capture
and sensor")

Cc: stable@vger.kernel.org # for v4.20
Signed-off-by: Lucas A. M. Magalhães <lucmaga@gmail.com>
Acked-by: Helen Koike <helen.koike@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
[hverkuil-cisco@xs4all.nl: fixed small space-after-tab issue in the patch]
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

1 files changed, 4 insertions, 24 deletions

diff --git a/drivers/media/platform/vimc/vimc-scaler.c b/drivers/media/platform/vimc/vimc-scaler.c
index b0952ee86296..39b2a73dfcc1 100644
--- a/drivers/media/platform/vimc/vimc-scaler.c
+++ b/drivers/media/platform/vimc/vimc-scaler.c
@@ -217,7 +217,6 @@ static const struct v4l2_subdev_pad_ops vimc_sca_pad_ops = {
 static int vimc_sca_s_stream(struct v4l2_subdev *sd, int enable)
 {
         struct vimc_sca_device *vsca = v4l2_get_subdevdata(sd);
-        int ret;
 
         if (enable) {
                 const struct vimc_pix_map *vpix;
@@ -245,22 +244,10 @@ static int vimc_sca_s_stream(struct v4l2_subdev *sd, int enable)
                 if (!vsca->src_frame)
                         return -ENOMEM;
 
-                /* Turn the stream on in the subdevices directly connected */
-                ret = vimc_pipeline_s_stream(&vsca->sd.entity, 1);
-                if (ret) {
-                        vfree(vsca->src_frame);
-                        vsca->src_frame = NULL;
-                        return ret;
-                }
         } else {
                 if (!vsca->src_frame)
                         return 0;
 
-                /* Disable streaming from the pipe */
-                ret = vimc_pipeline_s_stream(&vsca->sd.entity, 0);
-                if (ret)
-                        return ret;
-
                 vfree(vsca->src_frame);
                 vsca->src_frame = NULL;
         }
@@ -346,26 +333,19 @@ static void vimc_sca_fill_src_frame(const struct vimc_sca_device *const vsca,
                         vimc_sca_scale_pix(vsca, i, j, sink_frame);
 }
 
-static void vimc_sca_process_frame(struct vimc_ent_device *ved,
-                                   struct media_pad *sink,
-                                   const void *sink_frame)
+static void *vimc_sca_process_frame(struct vimc_ent_device *ved,
+                                    const void *sink_frame)
 {
         struct vimc_sca_device *vsca = container_of(ved, struct vimc_sca_device,
                                                     ved);
-        unsigned int i;
 
         /* If the stream in this node is not active, just return */
         if (!vsca->src_frame)
-                return;
+                return ERR_PTR(-EINVAL);
 
         vimc_sca_fill_src_frame(vsca, sink_frame);
 
-        /* Propagate the frame through all source pads */
-        for (i = 1; i < vsca->sd.entity.num_pads; i++) {
-                struct media_pad *pad = &vsca->sd.entity.pads[i];
-
-                vimc_propagate_frame(pad, vsca->src_frame);
-        }
+        return vsca->src_frame;
 };
 
 static void vimc_sca_comp_unbind(struct device *comp, struct device *master,