power: supply: rt5033_charger: Add cable detection and USB OTG supply

power: supply: rt5033_charger: Add cable detection and USB OTG supply

Implement cable detection by extcon and handle the driver according to the
connector type.

There are basically three types of action: "set_charging", "set_otg" and
"set_disconnect".

A forth helper function to "unset_otg" was added because this is used in both
"set_charging" and "set_disconnect". In the first case it covers the rather
rare event that someone changes from OTG to charging without disconnect. In
the second case, when disconnecting, the values are set back to the ones from
initialization to return into a defined state.

Additionally, there is "set_mivr". When connecting to e.g. a laptop/PC, the
minimum input voltage regulation (MIVR) shall prevent a voltage drop if the
cable or the supply is weak. The MIVR value is set to 4600MV, same as in the
Android driver [1]. When disconnecting, MIVR is set back to DISABLED.

In the function rt5033_get_charger_state(): When in OTG mode, the chip
reports status "charging". Change this to "discharging" because there is
no charging going on in OTG mode [2].

Yang Yingliang detected missing mutex_unlock() in some error path and
suggested a fix [3]. The suggestion was squashed into this patch.

[1] https://github.com/msm8916-mainline/linux-downstream/blob/GT-I9195I/drivers/battery/rt5033_charger.c#L499
[2] https://github.com/msm8916-mainline/linux-downstream/blob/GT-I9195I/drivers/battery/rt5033_charger.c#L686-L687
[3] https://lore.kernel.org/linux-pm/20230822030207.644738-1-yangyingliang@huawei.com

Tested-by: Raymond Hackley <raymondhackley@protonmail.com>
Co-developed-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Jakob Hauser <jahau@rocketmail.com>
Link: https://lore.kernel.org/r/cc4e37e510abbb0cdfa7faa8408da48c2cb448a4.1696165240.git.jahau@rocketmail.com
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>