hwmon: (corsair-psu) update Series 2022 and 2023 support

The series 2022/2023 reports slightly longer vendor/product strings
and shares USB ids. Technically the reply size is the USB HID packet
size (64 bytes) but all the supported commands do not use more than 8
bytes and replies reporting back strings do not use more then 24 bytes
(vendor and product are in one string in the newer devices now). The
rest of the reply is always filled with '\0'. Also update comments
and documentation accordingly.

Signed-off-by: Wilken Gottwalt <wilken.gottwalt@posteo.net>
Link: https://lore.kernel.org/r/ZJbB72CAPmLflhHG@monster.localdomain
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

hwmon: (corsair-psu) various cleanups

Fix some typos, adjust documentation and comments to current state of
knowledge and update coding style to be more uniform.

Signed-off-by: Wilken Gottwalt <wilken.gottwalt@posteo.net>
Link: https://lore.kernel.org/r/ZJWf3H972hGgLK-8@monster.localdomain
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

hwmon: (corsair-psu) add support for reading PWM values and mode

Add support for reading PWM values and mode,
and update documentation accordingly.

Signed-off-by: Wilken Gottwalt <wilken.gottwalt@posteo.net>
Link: https://lore.kernel.org/r/ZJSASByXpzoZ0XyH@monster.localdomain
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

Documentation: hwmon: correct spelling

Correct spelling problems for Documentation/hwmon/ as reported
by codespell.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Cc: Jean Delvare <jdelvare@suse.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: linux-hwmon@vger.kernel.org
Link: https://lore.kernel.org/r/20230129231053.20863-4-rdunlap@infradead.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

hwmon: (corsair-psu) Add USB id of the new HX1500i psu

Also update the documentation accordingly.

Signed-off-by: Wilken Gottwalt <wilken.gottwalt@posteo.net>
Link: https://lore.kernel.org/r/Y0FghqQCHG/cX5Jz@monster.localdomain
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

hwmon: (corsair-psu) add USB id of new revision of the HX1000i psu

Also updates the documentation accordingly.

Signed-off-by: Wilken Gottwalt <wilken.gottwalt@posteo.net>
Link: https://lore.kernel.org/r/YznOUQ7Pijedu0NW@monster.localdomain
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

hwmon: (corsair-psu) add reporting of rail mode via debugfs

Add reporting if the PSU is running in single or multi rail mode via
ocpmode debugfs entry. Also update the documentation and driver comments
accordingly.

Signed-off-by: Wilken Gottwalt <wilken.gottwalt@posteo.net>
Link: https://lore.kernel.org/r/YvS9PZKr0xqFqJny@monster.localdomain
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

hwmon: (corsair-psu) add support for critical values

Adds support for reading the critical values of the temperature sensors
and the rail sensors (voltage and current) once and caches them. Updates
the naming of the constants following a more clear scheme. Also updates
the documentation and fixes some typos. Updates is_visible and ops_read
functions to be more readable.

The new sensors output of a Corsair HX850i will look like this:
corsairpsu-hid-3-1
Adapter: HID adapter
v_in: 230.00 V
v_out +12v: 12.14 V (crit min = +8.41 V, crit max = +15.59 V)
v_out +5v: 5.03 V (crit min = +3.50 V, crit max = +6.50 V)
v_out +3.3v: 3.30 V (crit min = +2.31 V, crit max = +4.30 V)
psu fan: 0 RPM
vrm temp: +46.2°C (crit = +70.0°C)
case temp: +39.8°C (crit = +70.0°C)
power total: 152.00 W
power +12v: 108.00 W
power +5v: 41.00 W
power +3.3v: 5.00 W
curr +12v: 9.00 A (crit max = +85.00 A)
curr +5v: 8.31 A (crit max = +40.00 A)
curr +3.3v: 1.62 A (crit max = +40.00 A)

Signed-off-by: Wilken Gottwalt <wilken.gottwalt@posteo.net>
Link: https://lore.kernel.org/r/YFNg6vGk3sQmyqgB@monster.powergraphx.local
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

hwmon: add Corsair PSU HID controller driver

The Corsair digital power supplies of the series RMi, HXi and AXi include
a small micro-controller with a lot of sensors attached. The sensors can
be accessed by an USB connector from the outside.

This micro-controller provides the data by a simple proprietary USB HID
protocol. The data consist of temperatures, current and voltage levels,
power usage, uptimes, fan speed and some more. It is also possible to
configure the PSU (fan mode, mono/multi-rail, over current protection).

This driver provides access to the sensors/statistics of the RMi and HXi
series power supplies. It does not support configuring these devices,
because there would be many ways to misconfigure or even damage the PSU.

This patch adds:
- hwmon driver corsair-psu
- hwmon documentation
- updates MAINTAINERS

Signed-off-by: Wilken Gottwalt <wilken.gottwalt@posteo.net>
Link: https://lore.kernel.org/r/20201027131710.GA253280@monster.powergraphx.local
Signed-off-by: Guenter Roeck <linux@roeck-us.net>