[PATCH 02/14] drm/exynos: Remove exynos_plane_dpms() call with no effect

[Daniel Vetter]

On Thu, Feb 05, 2015 at 10:05:43AM +0900, Joonyoung Shim wrote:
> Hi Daniel,
> 
> On 02/04/2015 11:16 PM, Daniel Vetter wrote:
> > On Wed, Feb 04, 2015 at 04:42:57PM +0900, Joonyoung Shim wrote:
> >> Hi,
> >>
> >> On 02/04/2015 04:14 AM, Gustavo Padovan wrote:
> >>> From: Gustavo Padovan <gustavo.padovan at collabora.co.uk>
> >>>
> >>> exynos_plane_dpms(DRM_MODE_DPMS_ON) calls the win_enable()'s callback
> >>> from the underlying layer. However neither one of these layers implement
> >>> win_enable() - FIMD, Mixer and VIDI. Thus the call to exynos_plane_dpms()
> >>> is pointless.
> >>>
> >>> Signed-off-by: Gustavo Padovan <gustavo.padovan at collabora.co.uk>
> >>> ---
> >>>  drivers/gpu/drm/exynos/exynos_drm_crtc.c | 2 --
> >>>  1 file changed, 2 deletions(-)
> >>>
> >>> diff --git a/drivers/gpu/drm/exynos/exynos_drm_crtc.c b/drivers/gpu/drm/exynos/exynos_drm_crtc.c
> >>> index b2a4b84..ad675fb 100644
> >>> --- a/drivers/gpu/drm/exynos/exynos_drm_crtc.c
> >>> +++ b/drivers/gpu/drm/exynos/exynos_drm_crtc.c
> >>> @@ -65,8 +65,6 @@ static void exynos_drm_crtc_commit(struct drm_crtc *crtc)
> >>>  
> >>>  	if (exynos_crtc->ops->commit)
> >>>  		exynos_crtc->ops->commit(exynos_crtc);
> >>> -
> >>> -	exynos_plane_dpms(crtc->primary, DRM_MODE_DPMS_ON);
> >>
> >> As i said, this needs to keep pair enabled flag of struct
> >> exynos_drm_plane.
> > 
> > The reason exynos needs that exynos_plane->enable is because it has its
> > own per-plane dpms state. There's two problems with that:
> > - It's highyl non-standard, the drm kms way is to just disable the plane
> >   and not have some additional knob on top.
> > - The atomic helpers will not be able to handle this. They assume that
> >   there's only one dpms knob for the entire display pipeline, and
> >   per-plane enable/disable is handled by setting plane->state->crtc, which
> >   must be set iff plane->state->fb is set right now.
> > 
> > I recommend we rip this all out if we can adjust existing userspace to
> > stop using the "mode" property on planes and crtcs.
> > 
> > And with that non-standard exynos plane mode thing gone we can indeed rip
> > out exynos_plane_dpms and exynos_plane->enabled and just directly call
> > manager->ops->win_enable/disble. And then rip out the win_enable since
> > it's unused.
> 
> But this cleanup on current codes doesn't care now current operation
> normally. First let's cleanup non-standard exynos plane dpms state as
> you said.

Yeah my reply wasn't too clear, so let me clarify: I agree with you,
Padovan's patch as-is can't be merged. First we need to get rid of the
non-standard plane dpms stuff, then we can remove the ->win_enable hook
and then can we remove this call here.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch