The use of regmap in commit2f2c96338arequires REGMAP_I2C to be selected, in order to meet all dependencies. Fixes:2f2c96338a("iio: ltr501: Add regmap support.") Signed-off-by: Hartmut Knaack <knaack.h@gmx.de> Acked-by: Daniel Baluta <daniel.baluta@intel.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org>