[Intel-gfx] [PATCH v3 03/20] drm/dp: Move i2c init to drm_dp_aux_init, add __must_check and fini

[Lyude Paul]

On Thu, 2021-04-22 at 18:33 -0400, Lyude Paul wrote:
> OK - talked with Ville a bit on this and did some of my own research, I
> actually think that moving i2c to drm_dp_aux_init() is the right decision
> for
> the time being. The reasoning behind this being that as shown by my previous
> work of fixing drivers that call drm_dp_aux_register() too early - it seems
> like there's already been drivers that have been working just fine with
> setting up the i2c device before DRM registration. 
> 
> In the future, it'd probably be better if we can split up i2c_add_adapter()
> into an init and register function - but we'll have to talk with the i2c
> maintainers to see if this is acceptable w/ them

Actually - I think adding the ability to refcount dp aux adapters might be a
better solution so I'm going to try that!

> 
> On Thu, 2021-04-22 at 13:18 -0400, Lyude Paul wrote:
> > On Tue, 2021-04-20 at 02:16 +0300, Ville Syrjälä wrote:
> > > 
> > > The init vs. register split is intentional. Registering the thing
> > > and allowing userspace access to it before the rest of the driver
> > > is ready isn't particularly great. For a while now we've tried to
> > > move towards an architecture where the driver is fully initialzied
> > > before anything gets exposed to userspace.
> > 
> > Yeah-thank you for pointing this out. Thierry - do you think there's an
> > alternate solution we could go with in Tegra to fix the get_device() issue
> > that wouldn't require us trying to expose the i2c adapter early?
> > 
> > > 
> > 
> 

-- 
Cheers,
 Lyude Paul (she/her)
 Software Engineer at Red Hat