From mboxrd@z Thu Jan  1 00:00:00 1970
From: Hiroshi Doyu <hdoyu-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
Subject: Re: [PATCHv3 01/19] [HACK] of: dev_node has struct device pointer
Date: Fri, 25 Oct 2013 13:08:34 +0200
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References: <20131025091104.GG19622@ulmo.nvidia.com><20131025.124905.1154427805530939055.hdoyu@nvidia.com><20131025104937.GA25080@ulmo.nvidia.com>
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Thierry Reding <thierry.reding-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote @ Fri, 25 Oct 2013 12:49:38 +0200:

> The way notifiers work is that they run completely hidden from whatever
> triggers them. For instance you register the IOMMU bus notifier from the
> IOMMU driver (by calling bus_set_iommu()). That registers a function to
> be called when some event happens on that bus. When a device's driver is
> probed successfully, the driver core will notify the bus, which causes
> the IOMMU callback to be run.
> 
> Some of this code runs before the driver has successfully been probed,
> so I imagine it would be possible to use it to abort probing. But that's
> not possible at least with the current code.

At least I'll experiment this way to see if it's acceptable or not.

> > This looks somewhat similar to the above iommu_bus notifier.
> > 
> > Is there any way to implement the same mechanism rather than using
> > bus?
> 
> Yes, I think it should be possible to get this to work without using the
> bus notifier at all. I can try to code something up but wanted to wait
> for feedback from Grant first.

That's interesting too.