[PATCH v3 1/6] drm: document DRM_MODE_PAGE_FLIP_ASYNC

[Simon Ser <contact@emersion.fr>]

This is a subset of [1], included here because a subsequent patch
needs to document the behavior of this flag under the atomic uAPI.

v2: new patch

[1]: https://patchwork.freedesktop.org/patch/500177/

Signed-off-by: Simon Ser <contact@emersion.fr>
Reviewed-by: André Almeida <andrealmeid@igalia.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
---
 include/uapi/drm/drm_mode.h | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h
index fa953309d9ce..86a292c3185a 100644
--- a/include/uapi/drm/drm_mode.h
+++ b/include/uapi/drm/drm_mode.h
@@ -936,6 +936,13 @@ struct hdr_output_metadata {
 };
 
 #define DRM_MODE_PAGE_FLIP_EVENT 0x01
+/**
+ * DRM_MODE_PAGE_FLIP_ASYNC
+ *
+ * Request that the page-flip is performed as soon as possible, ie. with no
+ * delay due to waiting for vblank. This may cause tearing to be visible on
+ * the screen.
+ */
 #define DRM_MODE_PAGE_FLIP_ASYNC 0x02
 #define DRM_MODE_PAGE_FLIP_TARGET_ABSOLUTE 0x4
 #define DRM_MODE_PAGE_FLIP_TARGET_RELATIVE 0x8
-- 
2.37.3