media: renesas: vsp1: rpf: Fix crop left and top clamping

media: renesas: vsp1: rpf: Fix crop left and top clamping

The RPF doesn't enforces the alignment constraint on the sink pad
format, which could have an odd size, possibly down to 1x1. In that
case, the upper bounds for the left and top coordinates clamping would
become negative, cast to a very large positive value. Incorrect crop
rectangle coordinates would then be incorrectly accepted.

A second issue can occur when the requested left and top coordinates are
negative. They are cast to a large unsigned value, clamped to the
maximum. While the calculation will produce valid values for the
hardware, this is not compliant with the V4L2 specification that
requires values to be adjusted to the closest valid value.

Fix both issues by switching to signed clamping, with an explicit
minimum to adjust negative values, and adjusting the clamp bounds to
avoid negative upper bounds.

Tested-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # HiHope RZ/G2M
Link: https://patch.msgid.link/20260318235907.831556-5-laurent.pinchart+renesas@ideasonboard.com
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>