[media] media: Media device node support

The media_devnode structure provides support for registering and
unregistering character devices using a dynamic major number. Reference
counting is handled internally, making device drivers easier to write
without having to solve the open/disconnect race condition issue over
and over again.

The code is based on video/v4l2-dev.c.

[mchehab@redhat.com: Remove linux/smp_lock.h include to not break compilation on bisect]
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 13 insertions, 0 deletions

diff --git a/drivers/media/Kconfig b/drivers/media/Kconfig
index 81b3ba83cc65..2466f2b2ecfa 100644
--- a/drivers/media/Kconfig
+++ b/drivers/media/Kconfig
@@ -14,6 +14,19 @@ if MEDIA_SUPPORT
 comment "Multimedia core support"
 
 #
+# Media controller
+#
+
+config MEDIA_CONTROLLER
+        bool "Media Controller API (EXPERIMENTAL)"
+        depends on EXPERIMENTAL
+        ---help---
+          Enable the media controller API used to query media devices internal
+          topology and configure it dynamically.
+
+          This API is mostly used by camera interfaces in embedded platforms.
+
+#
 # V4L core and enabled API's
 #