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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135 The Voltage, Fan and Temperature Monitoring uses the standard sysfs
136 interface as documented in sysfs-interface, without any exceptions.
139 Fan Control
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142 Both PWM (pulse-width modulation) and DC fan speed control methods are
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
155 mode where the actual RPM of the fan (as measured) is controlled and the speed
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
159 whole lot of a difference when modifying fan control settings. The only
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
162 RPM mode, it will also set fan#_full_speed properly, if it does not then
163 fan control will not work properly, unless you set a sane fan#_full_speed
166 Switching between these modes requires re-initializing a whole bunch of
170 Three different fan control modes are supported; the mode number is written
177   fan#_full_speed by writing to the pwm# file. This mode is only
178   available on the F71858FG / F8000 if the fan channel is in RPM mode.
181   You can define a number of temperature/fan speed trip points, which % the
182   fan should run at at this temp and which temp a fan should follow using the
185   Fan/PWM channel 3 of the F8000 is always in this mode!
188   The fan speed is regulated to keep the temp the fan is mapped to between