[PATCH] drm: add more document for drm_crtc_from_index()

[Daniel Vetter]

On Sat, Jan 07, 2017 at 04:52:11PM +0800, Shawn Guo wrote:
> From: Shawn Guo <shawn.guo at linaro.org>
> 
> 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 at linaro.org>

Applied, thanks.
-Daniel

> ---
> This is a follow-up patch to address Daniel's comment [1] on my patch
> "[PATCH 1/3] drm: add crtc helper drm_crtc_from_index()".
> 
> Shawn
> 
> [1] http://www.spinics.net/lists/dri-devel/msg128062.html
> 
>  drivers/gpu/drm/drm_crtc.c  | 5 ++++-
>  drivers/gpu/drm/drm_plane.c | 2 +-
>  2 files changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
> index 5c1bb1f34697..85a7452d0fb4 100644
> --- a/drivers/gpu/drm/drm_crtc.c
> +++ b/drivers/gpu/drm/drm_crtc.c
> @@ -52,7 +52,10 @@
>   * @idx: index of registered CRTC to find for
>   *
>   * Given a CRTC index, return the registered CRTC from DRM device's
> - * list of CRTCs with matching index.
> + * list of CRTCs with matching index. This is the inverse of drm_crtc_index().
> + * It's useful in the vblank callbacks (like &drm_driver.enable_vblank or
> + * &drm_driver.disable_vblank), since that still deals with indices instead
> + * of pointers to &struct drm_crtc."
>   */
>  struct drm_crtc *drm_crtc_from_index(struct drm_device *dev, int idx)
>  {
> diff --git a/drivers/gpu/drm/drm_plane.c b/drivers/gpu/drm/drm_plane.c
> index 62b98f386fd1..535dec4f508d 100644
> --- a/drivers/gpu/drm/drm_plane.c
> +++ b/drivers/gpu/drm/drm_plane.c
> @@ -254,7 +254,7 @@ void drm_plane_cleanup(struct drm_plane *plane)
>   * @idx: index of registered plane to find for
>   *
>   * Given a plane index, return the registered plane from DRM device's
> - * list of planes with matching index.
> + * list of planes with matching index. This is the inverse of drm_plane_index().
>   */
>  struct drm_plane *
>  drm_plane_from_index(struct drm_device *dev, int idx)
> -- 
> 1.9.1
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch