[media] media: imx: Add a TODO file

Add a TODO file.
Signed-off-by: Steve Longerbeam <steve_longerbeam@mentor.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

drivers/staging/media/imx/TODO

+
+- Clean up and move the ov5642 subdev driver to drivers/media/i2c, or
+  merge support for OV5642 into drivers/media/i2c/ov5640.c, and create
+  the binding docs for it.
+
+- The Frame Interval Monitor could be exported to v4l2-core for
+  general use.
+
+- At driver load time, the device-tree node that is the original source
+  (the "sensor"), is parsed to record its media bus configuration, and
+  this info is required in imx-media-csi.c to setup the CSI.
+  Laurent Pinchart argues that instead the CSI subdev should call its
+  neighbor's g_mbus_config op (which should be propagated if necessary)
+  to get this info. However Hans Verkuil is planning to remove the
+  g_mbus_config op. For now this driver uses the parsed DT mbus config
+  method until this issue is resolved.
+
+- This media driver supports inheriting V4L2 controls to the
+  video capture devices, from the subdevices in the capture device's
+  pipeline. The controls for each capture device are updated in the
+  link_notify callback when the pipeline is modified. It should be
+  decided whether this feature is useful enough to make it generally
+  available by exporting to v4l2-core.