Hi Lee, Tidy, but I've noticed the logic got inverted along the way: > On Tue 09 Mar 2021, Lee Jones wrote: > On Tue, 09 Mar 2021, Mark Jonas wrote: > This is my suggestion: > > /* If SMBus Mode is not available, enter Two-Wire Mode */ > if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_I2C)) { Determine bus *is* I2C, so assume SMBus timings not supported... if (i2c_check_functionality(i2c->adapter, I2C_FUNC_I2C)) { > ret = regmap_update_bits(da9063->regmap, DA9063_REG_CONFIG_J, > DA9063_TWOWIRE_TO, DA9063_TWOWIRE_TO); ...and *clear* the (currently set by default) timeout bit: DA9063_TWOWIRE_TO, 0); > if (ret < 0) { > dev_err(da9063->dev, "Failed to set Two-Wire Bus > Mode\n"); > return -EIO; > } > } I think you're right to exclude a case; vendor motivation to override the TO default seems inherently trustworthy. Best regards, Adam