The Linux kernel regulator API requires that each system sets up the connections between the various voltage and current regulators in the system and the devices they supply, known as consumers within the regulator API. This is done using the struct device for the consumer device as the key for consumer access. This works well for things like platform devices which are generally always allocated at system startup but is not really usable with buses like I2C which only allocate the struct device late on during system startup.
To help work with these buses Linux 2.6.32 will follow the clock API and allow the use of the dev_name() for the device instead. A new field dev_name has been added to struct regulator_consumer_supply which should be used instead of dev – this is now the preferred mechanism. It is a simple string and so does not depend on any other initialization.
For those backporting the relevant commit is 744ea1d0b59bf084f19559b8f199b644fbb0899c.