[Intel-gfx] [PATCH 01/21] drm/i915: Adding drm helper function drm_plane_from_index().

[Konduru, Chandra]

> -----Original Message-----
> From: Daniel Vetter [mailto:daniel.vetter at ffwll.ch] On Behalf Of Daniel Vetter
> Sent: Tuesday, March 17, 2015 7:05 AM
> To: Konduru, Chandra
> Cc: intel-gfx at lists.freedesktop.org; Conselvan De Oliveira, Ander; Vetter, Daniel
> Subject: Re: [Intel-gfx] [PATCH 01/21] drm/i915: Adding drm helper function
> drm_plane_from_index().
> 
> On Sat, Mar 14, 2015 at 10:55:26PM -0700, Chandra Konduru wrote:
> > Adding drm helper function to return plane pointer from index where
> > index is a returned by drm_plane_index.
> >
> > Signed-off-by: Chandra Konduru <chandra.konduru at intel.com>
> > ---
> >  drivers/gpu/drm/drm_crtc.c |   20 ++++++++++++++++++++
> >  include/drm/drm_crtc.h     |    1 +
> >  2 files changed, 21 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
> > index 9f970c2..bbe573e1 100644
> > --- a/drivers/gpu/drm/drm_crtc.c
> > +++ b/drivers/gpu/drm/drm_crtc.c
> > @@ -1286,6 +1286,26 @@ unsigned int drm_plane_index(struct drm_plane
> > *plane)  EXPORT_SYMBOL(drm_plane_index);
> >
> >  /**
> > + * drm_plane_from_index - find the registered plane at an index
> > + * @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.
> > + */
> > +struct drm_plane *
> > +drm_plane_from_index(struct drm_device *dev, int idx) {
> > +	struct drm_plane *plane;
> > +
> > +	list_for_each_entry(plane, &dev->mode_config.plane_list, head) {
> > +		if (drm_plane_index(plane) == idx)
> > +			return plane;
> 
> Just a bikeshed, but you can do the same counting loop as in drm_plane_index
> and then return the plane as soon as idx = i. Avoids a nested double-loop on the
> plane_list.
> -Daniel

Agree, will send out updated patch to avoid nested loop.

> 
> > +	}
> > +	return NULL;
> > +}
> > +EXPORT_SYMBOL(drm_plane_from_index);
> > +
> > +/**
> >   * drm_plane_force_disable - Forcibly disable a plane
> >   * @plane: plane to disable
> >   *
> > diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h index
> > 7b5c661..6b30036 100644
> > --- a/include/drm/drm_crtc.h
> > +++ b/include/drm/drm_crtc.h
> > @@ -1264,6 +1264,7 @@ extern int drm_plane_init(struct drm_device *dev,
> >  			  bool is_primary);
> >  extern void drm_plane_cleanup(struct drm_plane *plane);  extern
> > unsigned int drm_plane_index(struct drm_plane *plane);
> > +extern struct drm_plane * drm_plane_from_index(struct drm_device
> > +*dev, int idx);
> >  extern void drm_plane_force_disable(struct drm_plane *plane);  extern
> > int drm_plane_check_pixel_format(const struct drm_plane *plane,
> >  					u32 format);
> > --
> > 1.7.9.5
> >
> > _______________________________________________
> > Intel-gfx mailing list
> > Intel-gfx at lists.freedesktop.org
> > http://lists.freedesktop.org/mailman/listinfo/intel-gfx
> 
> --
> Daniel Vetter
> Software Engineer, Intel Corporation
> http://blog.ffwll.ch