On 21.05.2012 16:58, Thierry Reding wrote:

I agree that reflecting the hardware hierarchy within the device tree makes
sense. I'll need to add some code to tear down child devices in the cleanup
path, but that shouldn't be too difficult.

However, adding a whole bus_type implementation would pretty much duplicate
the platform bus code. I guess host1x could just provide struct host1x_client
a set of corresponding APIs to create them, request channels, etc.

Hi,

There is a reason for existence of bus_type in Linux kernel. It exposes
the various busses to developers, and give a framework for drivers to
work in. It just makes the drivers easier to develop, and makes the big
picture easier to understand.

The problem is that bus_type is cumbersome to implement, and most
implementations seem to duplicate significant amount of code from
platform bus. This is the problem that we should tackle.

If I manage to get the boilerplate code in nvhost for bus_type small
enough, that's the structure we should use. If bus_type is just
inherently fat and broken, I'll need to migrate nvhost away from it.

Terje