PH1-LD4 and PH1-sLD8 SoCs have pins that support pin configuration
(pin biasing, drive strength control), but not pin-muxing.
Allow to fill the mux value table with -1 for those pins; pins with
mux value -1 will be skipped in the pin-mux set function. The mux
value type should be changed from "unsigned" to "int" in order to
accommodate -1 as a special case.
[ Linux commit: 363c90e743b50a432a91a211dd8b078d9df446e9 ]
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
PH1-LD11 and PH1-LD20 have much pin controlling in common, so I
added a single driver shared between them in the initial commit.
However, the Ethernet pin-mux settings I am going to add are
different with each other, and they may diverge more as the
progress of development. Split it into two dedicated drivers.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>