Documentation/hwmon/f71882fg.rst

103 	  This is the 64-pin variant of the F71889FG, they have the
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125 These chips also have fan controlling features, using either DC or PWM, in
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136 interface as documented in sysfs-interface, without any exceptions.
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142 Both PWM (pulse-width modulation) and DC fan speed control methods are
143 supported. The right one to use depends on external circuitry on the
149 vica versa. So the temperature zone trip points 1-4 (or 1-2) go from high temp
153 There are 2 modes to specify the speed of the fan, PWM duty cycle (or DC
154 voltage) mode, where 0-100% duty cycle (0-100% of 12V) is specified. And RPM
156 gets specified as 0-100% of the fan#_full_speed file.
158 Since both modes work in a 0-100% (mapped to 0-255) scale, there isn't a
160 important difference is that in RPM mode the 0-100% controls the fan speed
161 between 0-100% of fan#_full_speed. It is assumed that if the BIOS programs
166 Switching between these modes requires re-initializing a whole bunch of
171 to the pwm#_enable file. Note that not all modes are supported on all
172 chips, and some modes may only be available in RPM / PWM mode.
176   You ask for a specific PWM duty cycle / DC voltage or a specific % of
177   fan#_full_speed by writing to the pwm# file. This mode is only
185   Fan/PWM channel 3 of the F8000 is always in this mode!