Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/Documentation/hwmon/aspeed-pwm-tacho.rst b/Documentation/hwmon/aspeed-pwm-tacho.rst
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+Kernel driver aspeed-pwm-tacho
+==============================
+
+Supported chips:
+ ASPEED AST2400/2500
+
+Authors:
+ <jaghu@google.com>
+
+Description:
+------------
+This driver implements support for ASPEED AST2400/2500 PWM and Fan Tacho
+controller. The PWM controller supports upto 8 PWM outputs. The Fan tacho
+controller supports up to 16 tachometer inputs.
+
+The driver provides the following sensor accesses in sysfs:
+
+=============== ======= =====================================================
+fanX_input ro provide current fan rotation value in RPM as reported
+ by the fan to the device.
+
+pwmX rw get or set PWM fan control value. This is an integer
+ value between 0(off) and 255(full speed).
+=============== ======= =====================================================