> +	if (IS_ERR(new_fwnode))
> +		dev_info(&z->dev, "Failed to create fwnode for LTC2990, error: %ld\n",
> +			 PTR_ERR(new_fwnode));
> +	else {

Braces for both blocks. Did you run checkpatch?

> +		/*
> +		 * Store the fwnode so we can destroy it on .remove().
> +		 * Only store it on success, as fwnode_remove_software_node()
> +		 * is NULL safe, but not PTR_ERR safe.
> +		 */
> +		i2c->ltc2990_fwnode = new_fwnode;
> +		ltc2990_info.fwnode = new_fwnode;
> +
> +		i2c->ltc2990_client =
> +			i2c_new_probed_device(&i2c->adapter,
> +					      &ltc2990_info,
> +					      icy_ltc2990_addresses,
> +					      NULL);

i2c_new_device (or better, the new i2c_new_client_device) should be
sufficient, or? You only have one potential address.