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 <tim.kry...@linaro.org> Reviewed-by: Alex Elder <el...@linaro.org> --- 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 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
