drm/i915/color: Fix step discontinuity in Pre-CSC Gamma LUT

Clamp Segment 2 to the last user-provided LUT entry value instead of
hardcoding it to 1.0 (1 << 24) to fix a step discontinuity.

Link: https://lore.kernel.org/intel-gfx/20260521180143.2143262-1-sean@poorly.run/ #v1
Link: https://lore.kernel.org/intel-gfx/20260525135730.1122696-2-sean@poorly.run/ #v2

Changes in v2:
- Split out into separate patches for pre/post csc fixes
- Dropped loop bounds fix in favor of [1]

Changes in v3:
- Fix stale commit message

[1]- https://lore.kernel.org/r/20260519075245.383864-1-pranay.samala@intel.com

Signed-off-by: Sean Paul <seanpaul@google.com>
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
Reviewed-by: Chaitanya Kumar Borah <chaitanya.kumar.borah@intel.com>
Signed-off-by: Uma Shankar <uma.shankar@intel.com>
Link: https://patch.msgid.link/20260528230817.2455072-2-sean@poorly.run
This commit is contained in:
Sean Paul 2026-05-28 19:07:47 -04:00 • committed by Uma Shankar
commit de90ca97b2