drm: add more document for drm_crtc_from_index()
authorShawn Guo <shawn.guo@linaro.org>
Sat, 7 Jan 2017 08:52:11 +0000 (16:52 +0800)
committerDaniel Vetter <daniel.vetter@ffwll.ch>
Mon, 9 Jan 2017 10:24:16 +0000 (11:24 +0100)
commit931c670d209b64a6033c1a2857ff309eee88f9c8
treeb2618de534e01cc501f10453e75c16d4df7aa2d5
parenta09759e82f2d60823027e9d3391bbea40f919604
drm: add more document for drm_crtc_from_index()

Add a bit more document for function drm_crtc_from_index() to cross
link it with drm_crtc_from_index(), and explain that the function is
useful in vblank code.

While at it, add cross link comment for drm_plane_from_index() as well.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1483779131-19935-1-git-send-email-shawnguo@kernel.org
drivers/gpu/drm/drm_crtc.c
drivers/gpu/drm/drm_plane.c