On 08/05/14 22:33, Jason Gunthorpe wrote: > On Thu, May 08, 2014 at 06:37:49PM +0200, Sylwester Nawrocki wrote: >> This patch adds a helper function to unregister devices which >> were created by an of_platform_populate() call. The pattern >> used here can already be found in multiple drivers. This helper >> can now be used instead of repeating similar code in drivers. > > I have a driver that does this as well, and what I found is that the > remove must be in reverse order from the create or things explode, and > that assumes the DT is topologically sorted according to dependency > (so no deferred probe). > > AFAIK, there is no analog to deferred probe for removal, and > attempting to remove, say, a GPIO driver while an I2C bit bang is using > it just fails. Thanks for the feedback, I knew I could be missing some of nasty details like this. Looks like we need a complete implementation of of_platform_unpopulate(). Since the are cases where the remove order is insignificant, I'm wondering whether it still would be useful to have a helper like device_unregister_children() which would remove only direct children of a device ? At least this solves my current problem. Since the dependencies will likely never be fully described in DT I guess we would need to create a list while actually creating devices, to be able to walk in reverse order while destroying them. -- Regards, Sylwester -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
