[RFC 3/5] regulator: core: Only apply constraints if available on list voltage

[Javier Martinez Canillas <javier.martinez@collabora.co.uk>]

If a selector can't be used on a platform due to voltage constraints,
regulator_list_voltage() returns 0. Doing this unconditionally made
sense since constraints were set in machine_constraints_voltage() at
regulator registration time.

But for load switches that don't define a voltage output, the parent
supply voltage is used so the constraints should only be applied if
they were defined for the child regulators.

Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
---
 drivers/regulator/core.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index a3c3785..7472535 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -2228,9 +2228,11 @@ int regulator_list_voltage(struct regulator *regulator, unsigned selector)
 	}
 
 	if (ret > 0) {
-		if (ret < rdev->constraints->min_uV)
+		if (rdev->constraints->min_uV &&
+		    ret < rdev->constraints->min_uV)
 			ret = 0;
-		else if (ret > rdev->constraints->max_uV)
+		else if (rdev->constraints->max_uV &&
+			 ret > rdev->constraints->max_uV)
 			ret = 0;
 	}
 
-- 
2.0.0.rc2