Drivers that call regulator_get_optional are tolerant to the absence of
that regulator. By modifying the value returned from the stub function
to match that seen when a regulator isn't present, callers can wrap the
regulator logic with an IS_ERR based conditional even if they happen to
call regulator_is_supported_voltage. This improves efficiency as well
as eliminates the possibility for a very subtle bug.
Signed-off-by: Tim Kryger <[email protected]>
Reviewed-by: Alex Elder <[email protected]>
---
This change was proposed here: https://lkml.org/lkml/2014/4/16/627
include/linux/regulator/consumer.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/include/linux/regulator/consumer.h b/include/linux/regulator/consumer.h
index e530681..1a4a8c1 100644
--- a/include/linux/regulator/consumer.h
+++ b/include/linux/regulator/consumer.h
@@ -258,14 +258,14 @@ regulator_get_exclusive(struct device *dev, const char *id)
static inline struct regulator *__must_check
regulator_get_optional(struct device *dev, const char *id)
{
- return NULL;
+ return ERR_PTR(-ENODEV);
}
static inline struct regulator *__must_check
devm_regulator_get_optional(struct device *dev, const char *id)
{
- return NULL;
+ return ERR_PTR(-ENODEV);
}
static inline void regulator_put(struct regulator *regulator)
--
1.7.9.5
On Thu, Apr 17, 2014 at 11:55:24AM -0700, Tim Kryger wrote:
> Drivers that call regulator_get_optional are tolerant to the absence of
> that regulator. By modifying the value returned from the stub function
> to match that seen when a regulator isn't present, callers can wrap the
> regulator logic with an IS_ERR based conditional even if they happen to
> call regulator_is_supported_voltage. This improves efficiency as well
> as eliminates the possibility for a very subtle bug.
Applied, thanks.