[PATCH i-g-t v6 2/8] tests/kms_colorop_helper: only check if a given enum value exists

[Melissa Wen <mwen@igalia.com>]

Don't trigger unnecessary colorop property changes just to probe that a
prop enum exists and can be applied. Make can_use_colorop() read-only,
preventing atomic commit rejections after test skips.

Assisted-by: Claude:claude-opus-4-7
Tested-by: Alex Hung <alex.hung@amd.com>
Reviewed-by: Chaitanya Kumar Borah <chaitanya.kumar.borah@intel.com>
Signed-off-by: Melissa Wen <mwen@igalia.com>
---
 lib/igt_kms.c              | 26 ++++++++++++++++++++++++++
 lib/igt_kms.h              |  4 ++++
 tests/kms_colorop_helper.c |  4 +++-
 3 files changed, 33 insertions(+), 1 deletion(-)

diff --git a/lib/igt_kms.c b/lib/igt_kms.c
index 365fb0cc3..dcd62d46a 100644
--- a/lib/igt_kms.c
+++ b/lib/igt_kms.c
@@ -4515,6 +4515,32 @@ igt_colorop_replace_prop_blob(igt_colorop_t *colorop, enum igt_atomic_colorop_pr
 	igt_colorop_set_prop_changed(colorop, prop);
 }
 
+/**
+ * igt_colorop_has_prop_enum_value:
+ * @colorop: Target colorop.
+ * @prop: Enum property to check.
+ * @val: Enum value (as string) to look up.
+ *
+ * Read-only counterpart to igt_colorop_try_prop_enum(): returns whether
+ * @colorop's @prop accepts the enum value @val, without setting it or
+ * marking @prop as changed in IGT's cache.
+ *
+ * Returns: true if @val is a valid value of the enum @prop on @colorop.
+ */
+bool igt_colorop_has_prop_enum_value(igt_colorop_t *colorop,
+				     enum igt_atomic_colorop_properties prop,
+				     const char *val)
+{
+	igt_display_t *display = colorop->plane->crtc->display;
+	uint64_t uval;
+
+	igt_assert(colorop->props[prop]);
+
+	return igt_mode_object_get_prop_enum_value(display->drm_fd,
+						   colorop->props[prop],
+						   val, &uval);
+}
+
 /**
  * igt_colorop_try_prop_enum:
  * @colorop: Target colorop.
diff --git a/lib/igt_kms.h b/lib/igt_kms.h
index 9b8779a62..0949862dc 100644
--- a/lib/igt_kms.h
+++ b/lib/igt_kms.h
@@ -1032,6 +1032,10 @@ uint64_t igt_colorop_get_prop(igt_display_t *display, igt_colorop_t *colorop, en
 	} while (0)
 
 
+extern bool igt_colorop_has_prop_enum_value(igt_colorop_t *colorop,
+					    enum igt_atomic_colorop_properties prop,
+					    const char *val);
+
 extern bool igt_colorop_try_prop_enum(igt_colorop_t *colorop,
 				      enum igt_atomic_colorop_properties prop,
 				      const char *val);
diff --git a/tests/kms_colorop_helper.c b/tests/kms_colorop_helper.c
index 5c0baeb12..e612859f9 100644
--- a/tests/kms_colorop_helper.c
+++ b/tests/kms_colorop_helper.c
@@ -259,7 +259,9 @@ static bool can_use_colorop(igt_display_t *display, igt_colorop_t *colorop, kms_
 	switch (desired->type) {
 	case KMS_COLOROP_ENUMERATED_LUT1D:
 		if (igt_colorop_get_prop(display, colorop, IGT_COLOROP_TYPE) == DRM_COLOROP_1D_CURVE &&
-		    igt_colorop_try_prop_enum(colorop, IGT_COLOROP_CURVE_1D_TYPE, kms_colorop_lut1d_tf_names[desired->enumerated_lut1d_info.tf]))
+		    igt_colorop_has_prop_enum_value(colorop,
+						    IGT_COLOROP_CURVE_1D_TYPE,
+						    kms_colorop_lut1d_tf_names[desired->enumerated_lut1d_info.tf]))
 			return true;
 		return false;
 	case KMS_COLOROP_CTM_3X4:
-- 
2.53.0