media: ipu3-cio2: Return actual subdev format

media: ipu3-cio2: Return actual subdev format

commit 8160e86702e0807bd36d40f82648f9f9820b9d5a upstream.

Return actual subdev format on ipu3-cio2 subdev pads. The earlier
implementation was based on an infinite recursion that exhausted the
stack.

Reported-by: Tsuchiya Yuto <kitakar@gmail.com>
Fixes: c2a6a07afe4a ("media: intel-ipu3: cio2: add new MIPI-CSI2 driver")
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Bingbu Cao <bingbu.cao@intel.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: stable@vger.kernel.org # v4.16 and up
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>