[media] media: add CEC notifier support

Add support for CEC notifiers, which is used to convey CEC physical address
information from video drivers to their CEC counterpart driver(s).

Based on an earlier version from Russell King:

https://patchwork.kernel.org/patch/9277043/

The cec_notifier is a reference counted object containing the CEC physical address
state of a video device.

When a new notifier is registered the current state will be reported to
that notifier at registration time.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/drivers/media/Kconfig b/drivers/media/Kconfig
index 3512316e7a46..9e9ded44e8a8 100644
--- a/drivers/media/Kconfig
+++ b/drivers/media/Kconfig
@@ -99,6 +99,10 @@ config MEDIA_CEC_DEBUG
 config MEDIA_CEC_EDID
         bool
 
+config MEDIA_CEC_NOTIFIER
+        bool
+        select MEDIA_CEC_EDID
+
 #
 # Media controller
 #       Selectable only for webcam/grabbers, as other drivers don't use it