[PATCH] drm/i915: add check for valid init_clock_gating-pointer

[Jesse Barnes]

On Thu, 16 Jun 2011 15:28:46 +0200
Wolfram Sang <w.sang at pengutronix.de> wrote:

> > > Commit 6067aa (drm/i915: split clock gating init into per-chipset
> > > functions) unconditionally calls the newly created
> > > init_clock_gating-pointer. There is one case, however, where it does
> > > not get set:
> > > 
> > > if (HAS_PCH_SPLIT(dev)) {
> > > 	...
> > > 	} else
> > > 		dev_priv->display.update_wm = NULL;
> > > }
> > 
> > We'll only hit this path on non-existent hardware.  Since a clock
> > gating routine is required I'd rather just see the panic and add a new
> > routine at that time (i.e. what we normally do during bringup).
> 
> How about BUG_ON(!ptr) in the init-routine for a bit more grace? And/or
> a warning in the else-block? It seems to happen to users...

Yeah, a BUG_ON would be fine.

-- 
Jesse Barnes, Intel Open Source Technology Center