Previously the struct bus_type exported by the host1x infrastructure was
only a very basic skeleton. Turn that implementation into a more full-
fledged bus to support proper probe ordering and power management.
Note that the bus infrastructure needs to be available before any of the
drivers can be registered. This is automatically ensured if all drivers
are built as loadable modules (via symbol dependencies). If all drivers
are built-in there are no such guarantees and the link order determines
the initcall ordering. Adjust drivers/gpu/Makefile to make sure that the
host1x bus infrastructure is initialized prior to any of its users (only
drm/tegra currently).
v2: Fix building host1x and tegra-drm as modules
Reported-by: Dave Airlie <airlied@gmail.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Reviewed-by: Mark Zhang <markz@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
The Tegra DRM driver currently uses some infrastructure to defer the DRM
core initialization until all required devices have registered. The same
infrastructure can potentially be used by any other driver that requires
more than a single sub-device of the host1x module.
Make the infrastructure more generic and keep only the DRM specific code
in the DRM part of the driver. Eventually this will make it easy to move
the DRM driver part back to the DRM subsystem.
Signed-off-by: Thierry Reding <treding@nvidia.com>