mfd: syscon: Add syscon_regmap_lookup_by_phandle_optional() function.

This adds syscon_regmap_lookup_by_phandle_optional() function to get an
optional regmap.

It behaves the same as syscon_regmap_lookup_by_phandle() except where
there is no regmap phandle. In this case, instead of returning -ENODEV,
the function returns NULL. This makes error checking simpler when the
regmap phandle is optional.

Suggested-by: Nicolas Boichat <[email protected]>
Signed-off-by: Enric Balletbo i Serra <[email protected]>
Reviewed-by: Matthias Brugger <[email protected]>
Reviewed-by: Arnd Bergmann <[email protected]>
Signed-off-by: Lee Jones <[email protected]>

0 files changed, 0 insertions, 0 deletions