Re: [PATCH 02/10] Driver core: Add iommu_ops to bus_type

Roedel, Joerg
2011-09-12T12:36:35Z

On Mon, Sep 12, 2011 at 08:08:41AM -0400, Sethi Varun-B16395 wrote:
> > The IOMMUs are usually devices on the bus itself, so they are initialized
> > after the bus is set up and the devices on it are populated. So the
> > function can not be called on bus initialization because the IOMMU is not
> > ready at this point.
> Well, at what point would the add_device_group (referring to patch set posted by Alex) call back be invoked?

The details are up to Alex Williamson. One option is to register a
notifier for the bus in the iommu_bus_init() function and react to its
notifications.
I think in the end we will have a number of additional call-backs in the
iommu_ops which are called by the notifier (or from the driver-core
directly) to handle actions like added or removed devices. All the
infrastructure for that which is implemented in the iommu-drivers today
will then be in the iommu-core code.

Joerg

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