Re: [RFC PATCH] regulator: Fix recursive mutex lockdep warning

From: Srinivas Kandagatla
Date: Thu Aug 06 2015 - 07:02:01 EST



On 06/08/15 10:43, Mark Brown wrote:
On Wed, Aug 05, 2015 at 05:02:08PM +0100, Srinivas Kandagatla wrote:
A recursive lockdep warning occurs if you call regulator_set_voltage()
on a load switches that are modelled as regulators with a parent supply as
there is no nesting annotation for the rdev->mutex.
To avoid this warning, use the unlocked version of the get_voltage().

No, just completely removing the locking is broken - the locking is
there for a reason! This needs some lockdep dance, either something

Yes, I totally agree, removing locking would have more regressions.

like what we have for regmaps with a class per regulator or something

lock_class per regulator makes more sense, I will try to cookup an RFC patch.
more fancy but whatever's going on just hacking out locking to shut up
warnings from lockdep is clearly not a good idea.


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