Hello, Hans, Mauro I find in source code: v4l2-common.c: v4l2_i2c_new_subdev_board(), there is a comment: /* Note: by loading the module first we are certain that c- >driver will be set if the driver was found. If the module was not loaded first, then the i2c core tries to delay-load the module for us, and then c->driver is still NULL until the module is finally loaded. This delay-load mechanism doesn't work if other drivers want to use the i2c device, so explicitly loading the module is the best alternative. */ I find it added by commit: f0222c7d860f09a61bec5e500539f28db0184b38 it was added at year 2009, is this still an issue in newer kernel, like 4.14? BR. Ning.