[Intel-gfx] [PATCH 16/37] drm/hdlcd|mali: Drop drm_vblank_cleanup

[Liviu Dudau]

On Wed, May 31, 2017 at 01:03:34PM +0200, Daniel Vetter wrote:
> On Wed, May 31, 2017 at 12:57 PM, Liviu Dudau <liviu.dudau at arm.com> wrote:
> > On Wed, May 24, 2017 at 04:51:51PM +0200, Daniel Vetter wrote:
> >> IRQs are properly shut down, so it almost works as race-free shutdown.
> >> Except the irq is stopped after the vblank stuff, so boom anyway.
> >> Proper way would be to call drm_atomic_helper_shutdown before any of
> >> the kms things gets stopped. So no harm in removing the
> >> drm_vblank_cleanup here really.
> >
> > Slightly confused on the implied message in the commit text: is "Proper way
> > would be to call drm_atomic_helper_shutdown" a hint? A promise of a future
> > patch? A message to the future us on how to fix things if they blow up?
> >
> > If calling drm_atomic_helper_shutdown() is the proper thing to do, why does the
> > patch (and the series) avoids doing that? Lack of understanding of the driver's
> > internal workings? Then I want to help, if I can understand the new direction.
> 
> Yes, I wanted to not make things worse. If you look at the overall
> result (especially last patch) I'm also trying to better document
> stuff in the vblank area, but summarized, if you want to make sure
> that vblank processing has stopped, you need to call drm_vblank_off on
> each active crtc. The simplest way to get that is by using
> drm_atomic_helper_shutdown(). Calling drm_vblank_cleanup doesn't
> really do anything useful (see the last patch for the only valid
> usecase there ever was).

OK, so there should be a follow up patch adding drm_atomic_helper_shutdown(). I guess
I need to call dibs on it? :)

Best regards,
Liviu

> -Daniel
> -- 
> Daniel Vetter
> Software Engineer, Intel Corporation
> +41 (0) 79 365 57 48 - http://blog.ffwll.ch

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