[PATCH v4 2/5] drm/drm_property: require DRM_MODE_PROP_IMMUTABLE for single-value props

[Dmitry Baryshkov]

Document that DRM_MODE_PROP_IMMUTABLE must be set for the properties
that are immutable by definition - e.g. ranges with min == max or enums
with a single value. This matches the behaviour of the IGT tests, see
kms_properties.c / validate_range_prop(), validate_enum_prop(),
validate_bitmask_prop().

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov at linaro.org>
---
 include/drm/drm_property.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/include/drm/drm_property.h b/include/drm/drm_property.h
index 082f29156b3e..d78ec42de42f 100644
--- a/include/drm/drm_property.h
+++ b/include/drm/drm_property.h
@@ -162,6 +162,9 @@ struct drm_property {
 	 *     userspace, e.g. the EDID, or the connector path property on DP
 	 *     MST sinks. Kernel can update the value of an immutable property
 	 *     by calling drm_object_property_set_value().
+	 *     This flag MUST be set for all properties that have only a
+	 *     single value (e.g. min == max or if enum has only a single
+	 *     value).
 	 */
 	uint32_t flags;
 

-- 
2.39.2