From 9239effd53d47e3cd9c653830c8465c0a3a427dc Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Tue, 6 Jan 2015 13:57:55 -0300 Subject: [media] dvb-frontend: enable tuner link when the FE thread starts 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 --- drivers/media/dvb-core/dvb_frontend.c | 94 +++++++++++++++++++++++++++++++++++ 1 file changed, 94 insertions(+) (limited to 'drivers/media/dvb-core') 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(); -- cgit v1.2.3