[PATCH] drm: document uAPI page-flip flags

[Simon Ser]

Document flags accepted by the page-flip and atomic IOCTLs.

Signed-off-by: Simon Ser <contact at emersion.fr>
Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
---
 include/uapi/drm/drm_mode.h | 44 ++++++++++++++++++++++++++++++++++++-
 1 file changed, 43 insertions(+), 1 deletion(-)

diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h
index fa953309d9ce..e1b04ffd54c3 100644
--- a/include/uapi/drm/drm_mode.h
+++ b/include/uapi/drm/drm_mode.h
@@ -935,12 +935,30 @@ struct hdr_output_metadata {
 	};
 };
 
+/**
+ * DRM_MODE_PAGE_FLIP_EVENT
+ *
+ * Request that the kernel sends back a vblank event (see
+ * struct drm_event_vblank) when the page-flip is done.
+ */
 #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
 #define DRM_MODE_PAGE_FLIP_TARGET (DRM_MODE_PAGE_FLIP_TARGET_ABSOLUTE | \
 				   DRM_MODE_PAGE_FLIP_TARGET_RELATIVE)
+/**
+ * DRM_MODE_PAGE_FLIP_FLAGS
+ *
+ * Bitmask of flags suitable for &drm_mode_crtc_page_flip_target.flags.
+ */
 #define DRM_MODE_PAGE_FLIP_FLAGS (DRM_MODE_PAGE_FLIP_EVENT | \
 				  DRM_MODE_PAGE_FLIP_ASYNC | \
 				  DRM_MODE_PAGE_FLIP_TARGET)
@@ -1034,11 +1052,35 @@ struct drm_mode_destroy_dumb {
 	__u32 handle;
 };
 
-/* page-flip flags are valid, plus: */
+/**
+ * DRM_MODE_ATOMIC_TEST_ONLY
+ *
+ * Do not apply the atomic commit, instead check whether the hardware supports
+ * this configuration.
+ *
+ * See drm_mode_config_funcs.atomic_check for more details on test-only
+ * commits.
+ */
 #define DRM_MODE_ATOMIC_TEST_ONLY 0x0100
+/**
+ * DRM_MODE_ATOMIC_NONBLOCK
+ *
+ * Do not block while applying the atomic commit.
+ */
 #define DRM_MODE_ATOMIC_NONBLOCK  0x0200
+/**
+ * DRM_MODE_ATOMIC_ALLOW_MODESET
+ *
+ * Allow the update to result in visible artifacts such as a black screen.
+ */
 #define DRM_MODE_ATOMIC_ALLOW_MODESET 0x0400
 
+/**
+ * DRM_MODE_ATOMIC_FLAGS
+ *
+ * Bitfield of flags accepted by the &DRM_IOCTL_MODE_ATOMIC IOCTL in
+ * &drm_mode_atomic.flags.
+ */
 #define DRM_MODE_ATOMIC_FLAGS (\
 		DRM_MODE_PAGE_FLIP_EVENT |\
 		DRM_MODE_PAGE_FLIP_ASYNC |\
-- 
2.37.2