If the dvb frontend thread starts, the tuner should be switched
to the frontend. Add a code that ensures that this will happen,
using the media controller.
Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxx>
diff --git a/drivers/media/dvb-core/dvb_frontend.c b/drivers/media/dvb-core/dvb_frontend.c
index 2564422278df..50bc6056e914 100644
--- a/drivers/media/dvb-core/dvb_frontend.c
+++ b/drivers/media/dvb-core/dvb_frontend.c
@@ -590,12 +590,99 @@ static void dvb_frontend_wakeup(struct dvb_frontend *fe)
wake_up_interruptible(&fepriv->wait_queue);
}
+/**
+ * dvb_enable_media_tuner() - tries to enable the DVB tuner
+ *
+ * @fe: struct dvb_frontend pointer
+ *
+ * This function ensures that just one media tuner is enabled for a given
+ * frontend. It has two different behaviors:
+ * - For trivial devices with just one tuner:
+ * it just enables the existing tuner->fe link
+ * - For devices with more than one tuner:
+ * It is up to the driver to implement the logic that will enable one tuner
+ * and disable the other ones. However, if more than one tuner is enabled for
+ * the same frontend, it will print an error message and return -EINVAL.
+ *
+ * At return, it will return the error code returned by media_entity_setup_link,
+ * or 0 if everything is OK, if no tuner is linked to the frontend or if the
+ * mdev is NULL.
+ */
+static int dvb_enable_media_tuner(struct dvb_frontend *fe)
+{
+#ifdef CONFIG_MEDIA_CONTROLLER_DVB
+ struct dvb_frontend_private *fepriv = fe->frontend_priv;
+ struct dvb_adapter *adapter = fe->dvb;
+ struct media_device *mdev = adapter->mdev;
+ struct media_entity *entity, *source;
+ struct media_link *link, *found_link = NULL;
+ int i, ret, n_links = 0, active_links = 0;
+
+ if (!mdev)
+ return 0;
+
+ entity = fepriv->dvbdev->entity;
+ for (i = 0; i < entity->num_links; i++) {
+ link = &entity->links[i];
+ if (link->sink->entity == entity) {
+ found_link = link;
+ n_links++;
+ if (link->flags & MEDIA_LNK_FL_ENABLED)
+ active_links++;
+ }
+ }
+
+ if (!n_links || active_links == 1 || !found_link)
+ return 0;
+
+ /*
+ * If a frontend has more than one tuner linked, it is up to the driver
+ * to select with one will be the active one, as the frontend core can't
+ * guess. If the driver doesn't do that, it is a bug.
+ */
+ if (n_links > 1 && active_links != 1) {
+ dev_err(fe->dvb->device,
+ "WARNING: there are %d active links among %d tuners. This is a driver's bug!\n",
+ active_links, n_links);
+ return -EINVAL;
+ }
+
+ 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(fe->dvb->device,
+ "Couldn't change link %s->%s to %s. Error %d\n",
+ source->name, sink->name,
+ flags ? "enabled" : "disabled",
+ ret);
+ return ret;
+ } else
+ dev_dbg(fe->dvb->device,
+ "link %s->%s was %s\n",
+ source->name, sink->name,
+ flags ? "ENABLED" : "disabled");
+ }
+#endif
+ return 0;
+}
+
static int dvb_frontend_thread(void *data)
{
struct dvb_frontend *fe = data;
struct dvb_frontend_private *fepriv = fe->frontend_priv;
fe_status_t s;
enum dvbfe_algo algo;
+ int ret;
bool re_tune = false;
bool semheld = false;
@@ -609,6 +696,13 @@ static int dvb_frontend_thread(void *data)
fepriv->wakeup = 0;
fepriv->reinitialise = 0;
+ ret = dvb_enable_media_tuner(fe);
+ if (ret) {
+ /* FIXME: return an error if it fails */
+ dev_info(fe->dvb->device,
+ "proceeding with FE task\n");
+ }
+
dvb_frontend_init(fe);
set_freezable();
--
2.1.0
--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
