Pull regulator fixes from Mark Brown:
"A couple of things here:
- Fixes for pbias that didn't make it in during the merge window due
to the driver coming in via MMC. The conversion to use helpers is
a fix as it implements list_voltage() which the main user (MMC)
relies on for correct functioning.
- Change the !REGULATOR stub for optional regulators to return an
error rather than a dummy; this is more in keeping with the
intended use of optional regulators and fixes some issues seen MMC
where it got confused by a dummy being provided"
* tag 'regulator-v3.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator:
regulator: core: Return error in get optional stub
regulator: pbias: Convert to use regmap helper functions
regulator: pbias: Fix is_enabled callback implementation