It is still a bit unclear, as the chipset manufactureer has not provided detailed descriptions.
I think that the 17.01 branch may have only four sensors available, but master has 11 since this commit in early 2017:
https://git.lede-project.org/?p=source.git;a=commitdiff;h=dc32d0a53cc01d9f644c6e9851b6770440d4b28c
The earlier implementation, still there in 17.01:
https://git.lede-project.org/?p=source.git;a=commitdiff;h=fef6a96d9e9e001a28b6a673c56ed79029457b5d