The ISP8000Nano v18.02 (found in the i.MX8MP) requires the ISP to be
enabled (as indicated by the ISP_CTRL.ISP_ENABLE bit) to configure the
lens shading table in internal RAM. The driver currently configures all
ISP initial parameters before enabling the ISP, which causes the LSC RAM
to not be initialized properly.

To fix this, split the rkisp1_params_configure() function into a
rkisp1_params_pre_configure() and a rkisp1_params_post_configure(). The
former configures all ISP parameters but LSC, while the latter
configures LSC. To implement this, the rkisp1_params_apply_params_cfg()
function is deconstructed, with two small helpers created to deal with
the parameters buffers, which are then used in rkisp1_params_isr(),
rkisp1_params_pre_configure() and rkisp1_params_post_configure().

While this initialization ordering is only needed for the ISP8000Nano
v18.02, it doesn't affect other ISP versions negatively, and can thus be
followed unconditionally.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Dafna Hirschfeld <dafna@fastmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>