[Intel-gfx] [PATCH 4/6] drm/i915: Make intel_get_pipe_from_connector atomic

[Daniel Vetter]

On Tue, Dec 20, 2016 at 02:35:40PM +0100, Maarten Lankhorst wrote:
> Op 19-12-16 om 09:24 schreef Daniel Vetter:
> > Drive-by fixup while looking at all the connector_list walkers -
> > holding connection_mutex does actually _not_ give you locking to look
> > at the legacy drm_connector->encoder->crtc pointer chain. That one is
> > solely owned by the atomic commit workers. Instead we must inspect the
> > atomic state.
> >
> > Signed-off-by: Daniel Vetter <daniel.vetter at intel.com>
> > ---
> >  drivers/gpu/drm/i915/intel_display.c | 5 ++---
> >  1 file changed, 2 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> > index 0b0d7e8be630..438d27f93aca 100644
> > --- a/drivers/gpu/drm/i915/intel_display.c
> > +++ b/drivers/gpu/drm/i915/intel_display.c
> > @@ -15427,15 +15427,14 @@ static int intel_crtc_init(struct drm_i915_private *dev_priv, enum pipe pipe)
> >  
> >  enum pipe intel_get_pipe_from_connector(struct intel_connector *connector)
> >  {
> > -	struct drm_encoder *encoder = connector->base.encoder;
> >  	struct drm_device *dev = connector->base.dev;
> >  
> >  	WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
> >  
> > -	if (!encoder || WARN_ON(!encoder->crtc))
> > +	if (!connector->base.state->crtc)
> >  		return INVALID_PIPE;
> >  
> > -	return to_intel_crtc(encoder->crtc)->pipe;
> > +	return to_intel_crtc(connector->base.state->crtc)->pipe;
> >  }
> >  
> >  int intel_get_pipe_from_crtc_id(struct drm_device *dev, void *data,
> 
> This patch clashes with the previous patch. intel_panel_set_backlight_acpi is called
> from asle_set_backlight. You should probably keep connection_mutex alive for it.

Oh, I've forgotten to update the commit message for the previous patch - I
ended up _not_ nuking the locking because it did blow up here ;-)

r-b on both if I fix up the previous commit message that we can't nuke the
locking because the asle_set_backlight thing needs it for the backlight
callbacks?
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch