media: rcar-vin: Create a group notifier

As CSI-2 subdevices are shared between several VIN instances, a shared
notifier to collect the CSI-2 async subdevices is required. So far, the
rcar-vin driver used the notifier of the last VIN instance to probe but
with the forth-coming introduction of parallel input subdevices support
in mc-compliant code path, each VIN may register its own notifier if any
parallel subdevice is connected there.

To avoid registering a notifier twice (once for parallel subdev and one
for the CSI-2 subdevs) create a group notifier, shared by all the VIN
instances.

Signed-off-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Acked-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

diff --git a/drivers/media/platform/rcar-vin/rcar-core.c b/drivers/media/platform/rcar-vin/rcar-core.c
index 1548b409806d8d92745ec8fa5fdb4c12d8a3710d..735e6ac66e4843cdb427b224c5f9ee1ad7114962 100644 (file)
--- a/drivers/media/platform/rcar-vin/rcar-core.c
+++ b/drivers/media/platform/rcar-vin/rcar-core.c
@@ -46,6 +46,8 @@
  */
 #define rvin_group_id_to_master(vin) ((vin) < 4 ? 0 : 4)
 
+#define v4l2_dev_to_vin(d)     container_of(d, struct rvin_dev, v4l2_dev)
+
 /* -----------------------------------------------------------------------------
  * Media Controller link notification
  */
@@ -359,8 +361,6 @@ out:
  * Async notifier
  */
 
-#define notifier_to_vin(n) container_of(n, struct rvin_dev, notifier)
-
 static int rvin_find_pad(struct v4l2_subdev *sd, int direction)
 {
        unsigned int pad;
@@ -466,7 +466,7 @@ static void rvin_parallel_subdevice_detach(struct rvin_dev *vin)
 
 static int rvin_parallel_notify_complete(struct v4l2_async_notifier *notifier)
 {
-       struct rvin_dev *vin = notifier_to_vin(notifier);
+       struct rvin_dev *vin = v4l2_dev_to_vin(notifier->v4l2_dev);
        int ret;
 
        ret = v4l2_device_register_subdev_nodes(&vin->v4l2_dev);
@@ -482,7 +482,7 @@ static void rvin_parallel_notify_unbind(struct v4l2_async_notifier *notifier,
                                        struct v4l2_subdev *subdev,
                                        struct v4l2_async_subdev *asd)
 {
-       struct rvin_dev *vin = notifier_to_vin(notifier);
+       struct rvin_dev *vin = v4l2_dev_to_vin(notifier->v4l2_dev);
 
        vin_dbg(vin, "unbind parallel subdev %s\n", subdev->name);
 
@@ -495,7 +495,7 @@ static int rvin_parallel_notify_bound(struct v4l2_async_notifier *notifier,
                                      struct v4l2_subdev *subdev,
                                      struct v4l2_async_subdev *asd)
 {
-       struct rvin_dev *vin = notifier_to_vin(notifier);
+       struct rvin_dev *vin = v4l2_dev_to_vin(notifier->v4l2_dev);
        int ret;
 
        mutex_lock(&vin->lock);
@@ -583,7 +583,7 @@ static int rvin_parallel_graph_init(struct rvin_dev *vin)
 
 static int rvin_group_notify_complete(struct v4l2_async_notifier *notifier)
 {
-       struct rvin_dev *vin = notifier_to_vin(notifier);
+       struct rvin_dev *vin = v4l2_dev_to_vin(notifier->v4l2_dev);
        const struct rvin_group_route *route;
        unsigned int i;
        int ret;
@@ -649,7 +649,7 @@ static void rvin_group_notify_unbind(struct v4l2_async_notifier *notifier,
                                     struct v4l2_subdev *subdev,
                                     struct v4l2_async_subdev *asd)
 {
-       struct rvin_dev *vin = notifier_to_vin(notifier);
+       struct rvin_dev *vin = v4l2_dev_to_vin(notifier->v4l2_dev);
        unsigned int i;
 
        for (i = 0; i < RCAR_VIN_NUM; i++)
@@ -673,7 +673,7 @@ static int rvin_group_notify_bound(struct v4l2_async_notifier *notifier,
                                   struct v4l2_subdev *subdev,
                                   struct v4l2_async_subdev *asd)
 {
-       struct rvin_dev *vin = notifier_to_vin(notifier);
+       struct rvin_dev *vin = v4l2_dev_to_vin(notifier->v4l2_dev);
        unsigned int i;
 
        mutex_lock(&vin->group->lock);
@@ -734,12 +734,6 @@ static int rvin_mc_parse_of_graph(struct rvin_dev *vin)
 
        mutex_lock(&vin->group->lock);
 
-       /* If there already is a notifier something has gone wrong, bail out. */
-       if (WARN_ON(vin->group->notifier)) {
-               mutex_unlock(&vin->group->lock);
-               return -EINVAL;
-       }
-
        /* If not all VIN's are registered don't register the notifier. */
        for (i = 0; i < RCAR_VIN_NUM; i++)
                if (vin->group->vin[i])
@@ -751,19 +745,16 @@ static int rvin_mc_parse_of_graph(struct rvin_dev *vin)
        }
 
        /*
-        * Have all VIN's look for subdevices. Some subdevices will overlap
-        * but the parser function can handle it, so each subdevice will
-        * only be registered once with the notifier.
+        * Have all VIN's look for CSI-2 subdevices. Some subdevices will
+        * overlap but the parser function can handle it, so each subdevice
+        * will only be registered once with the group notifier.
         */
-
-       vin->group->notifier = &vin->notifier;
-
        for (i = 0; i < RCAR_VIN_NUM; i++) {
                if (!vin->group->vin[i])
                        continue;
 
                ret = v4l2_async_notifier_parse_fwnode_endpoints_by_port(
-                               vin->group->vin[i]->dev, vin->group->notifier,
+                               vin->group->vin[i]->dev, &vin->group->notifier,
                                sizeof(struct v4l2_async_subdev), 1,
                                rvin_mc_parse_of_endpoint);
                if (ret) {
@@ -774,9 +765,12 @@ static int rvin_mc_parse_of_graph(struct rvin_dev *vin)
 
        mutex_unlock(&vin->group->lock);
 
-       vin->group->notifier->ops = &rvin_group_notify_ops;
+       if (!vin->group->notifier.num_subdevs)
+               return 0;
 
-       ret = v4l2_async_notifier_register(&vin->v4l2_dev, &vin->notifier);
+       vin->group->notifier.ops = &rvin_group_notify_ops;
+       ret = v4l2_async_notifier_register(&vin->v4l2_dev,
+                                          &vin->group->notifier);
        if (ret < 0) {
                vin_err(vin, "Notifier registration failed\n");
                return ret;
@@ -1162,8 +1156,10 @@ static int rcar_vin_remove(struct platform_device *pdev)
 
        if (vin->info->use_mc) {
                mutex_lock(&vin->group->lock);
-               if (vin->group->notifier == &vin->notifier)
-                       vin->group->notifier = NULL;
+               if (&vin->v4l2_dev == vin->group->notifier.v4l2_dev) {
+                       v4l2_async_notifier_unregister(&vin->group->notifier);
+                       v4l2_async_notifier_cleanup(&vin->group->notifier);
+               }
                mutex_unlock(&vin->group->lock);
                rvin_group_put(vin);
        } else {

diff --git a/drivers/media/platform/rcar-vin/rcar-vin.h b/drivers/media/platform/rcar-vin/rcar-vin.h
index b89f63b8ecdce40e027c9c474b98bf6c7e024504..17b4de4d273487840c49a91c958ae702a3e13554 100644 (file)
--- a/drivers/media/platform/rcar-vin/rcar-vin.h
+++ b/drivers/media/platform/rcar-vin/rcar-vin.h
@@ -227,8 +227,7 @@ struct rvin_dev {
  *
  * @lock:              protects the count, notifier, vin and csi members
  * @count:             number of enabled VIN instances found in DT
- * @notifier:          pointer to the notifier of a VIN which handles the
- *                     groups async sub-devices.
+ * @notifier:          group notifier for CSI-2 async subdevices
  * @vin:               VIN instances which are part of the group
  * @csi:               array of pairs of fwnode and subdev pointers
  *                     to all CSI-2 subdevices.
@@ -240,7 +239,7 @@ struct rvin_group {
 
        struct mutex lock;
        unsigned int count;
-       struct v4l2_async_notifier *notifier;
+       struct v4l2_async_notifier notifier;
        struct rvin_dev *vin[RCAR_VIN_NUM];
 
        struct {