[PATCH v3 20/22] media: dvb-frontend invoke enable/disable_source handlers

Shuah Khan
2016-02-11T23:42:40Z

Change dvb frontend to check if tuner is free when
device opened in RW mode. Call to enable_source
handler either returns with an active pipeline to
tuner or error if tuner is busy. Tuner is released
when frontend is released calling the disable_source
handler.

Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
---
drivers/media/dvb-core/dvb_frontend.c | 135 ++++++----------------------------
1 file changed, 21 insertions(+), 114 deletions(-)

diff --git a/drivers/media/dvb-core/dvb_frontend.c b/drivers/media/dvb-core/dvb_frontend.c
index 03cc508..8221fa6 100644
--- a/drivers/media/dvb-core/dvb_frontend.c
+++ b/drivers/media/dvb-core/dvb_frontend.c
@@ -134,7 +134,6 @@ struct dvb_frontend_private {

#if defined(CONFIG_MEDIA_CONTROLLER_DVB)
struct media_pipeline pipe;
- struct media_entity *pipe_start_entity;
#endif
};

@@ -596,104 +595,12 @@ 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.
- */
-#ifdef CONFIG_MEDIA_CONTROLLER_DVB
-static int dvb_enable_media_tuner(struct dvb_frontend *fe)
-{
- 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 ret, n_links = 0, active_links = 0;
-
- fepriv->pipe_start_entity = NULL;
-
- if (!mdev)
- return 0;
-
- entity = fepriv->dvbdev->entity;
- fepriv->pipe_start_entity = entity;
-
- list_for_each_entry(link, &entity->links, list) {
- 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;
- fepriv->pipe_start_entity = source;
- list_for_each_entry(link, &source->links, list) {
- struct media_entity *sink;
- int flags = 0;
-
- 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");
- }
- return 0;
-}
-#endif
-
static int dvb_frontend_thread(void *data)
{
struct dvb_frontend *fe = data;
struct dvb_frontend_private *fepriv = fe->frontend_priv;
enum fe_status s;
enum dvbfe_algo algo;
-#ifdef CONFIG_MEDIA_CONTROLLER_DVB
- int ret;
-#endif
-
bool re_tune = false;
bool semheld = false;

@@ -706,20 +613,6 @@ static int dvb_frontend_thread(void *data)
fepriv->wakeup = 0;
fepriv->reinitialise = 0;

-#ifdef CONFIG_MEDIA_CONTROLLER_DVB
- 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");
- } else if (fepriv->pipe_start_entity) {
- ret = media_entity_pipeline_start(fepriv->pipe_start_entity,
- &fepriv->pipe);
- if (ret)
- return ret;
- }
-#endif
-
dvb_frontend_init(fe);

set_freezable();
@@ -829,12 +722,6 @@ restart:
}
}

-#ifdef CONFIG_MEDIA_CONTROLLER_DVB
- if (fepriv->pipe_start_entity)
- media_entity_pipeline_stop(fepriv->pipe_start_entity);
- fepriv->pipe_start_entity = NULL;
-#endif
-
if (dvb_powerdown_on_sleep) {
if (fe->ops.set_voltage)
fe->ops.set_voltage(fe, SEC_VOLTAGE_OFF);
@@ -2612,9 +2499,20 @@ static int dvb_frontend_open(struct inode *inode, struct file *file)
fepriv->tone = -1;
fepriv->voltage = -1;

+#ifdef CONFIG_MEDIA_CONTROLLER_DVB
+ if (fe->dvb->mdev && fe->dvb->mdev->enable_source) {
+ ret = fe->dvb->mdev->enable_source(dvbdev->entity,
+ &fepriv->pipe);
+ if (ret) {
+ dev_err(fe->dvb->device,
+ "Tuner is busy. Error %d\n", ret);
+ goto err2;
+ }
+ }
+#endif
ret = dvb_frontend_start (fe);
if (ret)
- goto err2;
+ goto err3;

/* empty event queue */
fepriv->events.eventr = fepriv->events.eventw = 0;
@@ -2624,7 +2522,12 @@ static int dvb_frontend_open(struct inode *inode, struct file *file)
mutex_unlock (&adapter->mfe_lock);
return ret;

+err3:
+#ifdef CONFIG_MEDIA_CONTROLLER_DVB
+ if (fe->dvb->mdev && fe->dvb->mdev->disable_source)
+ fe->dvb->mdev->disable_source(dvbdev->entity);
err2:
+#endif
dvb_generic_release(inode, file);
err1:
if (dvbdev->users == -1 && fe->ops.ts_bus_ctrl)
@@ -2653,6 +2556,10 @@ static int dvb_frontend_release(struct inode *inode, struct file *file)

if (dvbdev->users == -1) {
wake_up(&fepriv->wait_queue);
+#ifdef CONFIG_MEDIA_CONTROLLER_DVB
+ if (fe->dvb->mdev && fe->dvb->mdev->disable_source)
+ fe->dvb->mdev->disable_source(dvbdev->entity);
+#endif
if (fe->exit != DVB_FE_NO_EXIT)
wake_up(&dvbdev->wait_queue);
if (fe->ops.ts_bus_ctrl)
--
2.5.0