[media] cx231xx: enable tuner->decoder link at videobuf start

The tuner->decoder needs to be enabled when we're about to
start streaming.

Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

diff --git a/drivers/media/usb/cx231xx/cx231xx-video.c b/drivers/media/usb/cx231xx/cx231xx-video.c
index f3d1a48..6347635 100644 (file)
--- a/drivers/media/usb/cx231xx/cx231xx-video.c
+++ b/drivers/media/usb/cx231xx/cx231xx-video.c
@@ -703,6 +703,74 @@ static void free_buffer(struct videobuf_queue *vq, struct cx231xx_buffer *buf)
        buf->vb.state = VIDEOBUF_NEEDS_INIT;
 }
 
+static int cx231xx_enable_analog_tuner(struct cx231xx *dev)
+{
+#ifdef CONFIG_MEDIA_CONTROLLER
+       struct media_device *mdev = dev->media_dev;
+       struct media_entity  *entity, *decoder = NULL, *source;
+       struct media_link *link, *found_link = NULL;
+       int i, ret, active_links = 0;
+
+       if (!mdev)
+               return 0;
+
+/*
+ * This will find the tuner that it is connected into the decoder.
+ * Technically, this is not 100% correct, as the device may be using an
+ * analog input instead of the tuner. However, we can't use the DVB for dvb
+ * while the DMA engine is being used for V4L2.
+ */
+       media_device_for_each_entity(entity, mdev) {
+               if (entity->type == MEDIA_ENT_T_V4L2_SUBDEV_DECODER) {
+                       decoder = entity;
+                       break;
+               }
+       }
+       if (!decoder)
+               return 0;
+
+       for (i = 0; i < decoder->num_links; i++) {
+               link = &decoder->links[i];
+               if (link->sink->entity == decoder) {
+                       found_link = link;
+                       if (link->flags & MEDIA_LNK_FL_ENABLED)
+                               active_links++;
+                       break;
+               }
+       }
+
+       if (active_links == 1 || !found_link)
+               return 0;
+
+       source = found_link->source->entity;
+       for (i = 0; i < source->num_links; i++) {
+               struct media_entity *sink;
+               int flags = 0;
+
+               link = &source->links[i];
+               sink = link->sink->entity;
+
+               if (sink == entity)
+                       flags = MEDIA_LNK_FL_ENABLED;
+
+               ret = media_entity_setup_link(link, flags);
+               if (ret) {
+                       dev_err(dev->dev,
+                               "Couldn't change link %s->%s to %s. Error %d\n",
+                               source->name, sink->name,
+                               flags ? "enabled" : "disabled",
+                               ret);
+                       return ret;
+               } else
+                       dev_dbg(dev->dev,
+                               "link %s->%s was %s\n",
+                               source->name, sink->name,
+                               flags ? "ENABLED" : "disabled");
+       }
+#endif
+       return 0;
+}
+
 static int
 buffer_prepare(struct videobuf_queue *vq, struct videobuf_buffer *vb,
               enum v4l2_field field)
@@ -756,6 +824,9 @@ buffer_prepare(struct videobuf_queue *vq, struct videobuf_buffer *vb,
        }
 
        buf->vb.state = VIDEOBUF_PREPARED;
+
+       cx231xx_enable_analog_tuner(dev);
+
        return 0;
 
 fail: