hwmon: (asus-ec-sensors) update documentation

Signed-off-by: Eugene Shalygin <eugene.shalygin@gmail.com>
Link: https://lore.kernel.org/r/20220124015658.687309-3-eugene.shalygin@gmail.comTested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Tested-by: Denis Pauk <pauk.denis@gmail.com>
[groeck: update index.rst, do not drop asus_wmi_ec_sensors.rst]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

Documentation/hwmon/asus_ec_sensors.rst

+.. SPDX-License-Identifier: GPL-2.0-or-later
+
+Kernel driver asus_ec_sensors
+=================================
+
+Supported boards:
+ * PRIME X570-PRO,
+ * Pro WS X570-ACE,
+ * ROG CROSSHAIR VIII DARK HERO,
+ * ROG CROSSHAIR VIII FORMULA,
+ * ROG CROSSHAIR VIII HERO,
+ * ROG CROSSHAIR VIII IMPACT,
+ * ROG STRIX B550-E GAMING,
+ * ROG STRIX B550-I GAMING,
+ * ROG STRIX X570-E GAMING,
+ * ROG STRIX X570-F GAMING,
+ * ROG STRIX X570-I GAMING
+
+Authors:
+    - Eugene Shalygin <eugene.shalygin@gmail.com>
+
+Description:
+------------
+ASUS mainboards publish hardware monitoring information via Super I/O
+chip and the ACPI embedded controller (EC) registers. Some of the sensors
+are only available via the EC.
+
+The driver is aware of and reads the following sensors:
+
+1. Chipset (PCH) temperature
+2. CPU package temperature
+3. Motherboard temperature
+4. Readings from the T_Sensor header
+5. VRM temperature
+6. CPU_Opt fan RPM
+7. VRM heatsink fan RPM
+8. Chipset fan RPM
+9. Readings from the "Water flow meter" header (RPM)
+10. Readings from the "Water In" and "Water Out" temperature headers
+11. CPU current
+
+Sensor values are read from EC registers, and to avoid race with the board
+firmware the driver acquires ACPI mutex, the one used by the WMI when its
+methods access the EC.
+
+Module Parameters
+-----------------
+ * mutex_path: string
+		The driver holds path to the ACPI mutex for each board (actually,
+		the path is mostly identical for them). If ASUS changes this path
+		in a future BIOS update, this parameter can be used to override
+		the stored in the driver value until it gets updated.

Documentation/hwmon/index.rst

@@ -43,6 +43,7 @@ Hardware Monitoring Kernel Drivers
    asb100
    asc7621
    aspeed-pwm-tacho
+   asus_ec_sensors
    asus_wmi_ec_sensors
    asus_wmi_sensors
    bcm54140