Documentation/hwmon/nct6775.rst

19   * Nuvoton NCT5572D/NCT6771F/NCT6772F/NCT6775F/W83677HG-I
83   * Nuvoton NCT6796D-S/NCT6799D-R
93 	Guenter Roeck <linux@roeck-us.net>
96 -----------
104 can be monitored and compared against minimum, maximum, and critical
106 There are 4 to 5 fan rotation speed sensors, 8 to 15 analog voltage sensors,
120 triggered if the rotation speed has dropped below a programmable limit. On
123 do not have a fan speed divider. The driver sets the most suitable fan divisor
124 itself; specifically, it increases the divider value each time a fan speed
125 reading returns an invalid value, and it reduces it if the fan speed reading
131 or maximum limit.
138 The mode works for fan1-fan5.
141 ----------------
143 pwm[1-7]
144     - this file stores PWM duty cycle or DC value (fan speed) in range:
146 	   0 (lowest speed) to 255 (full)
148 pwm[1-7]_enable
149     - this file controls mode of fan/temperature control:
151 	* 0 Fan control disabled (fans set to maximum speed)
152 	* 1 Manual mode, write to pwm[0-5] any value 0-255
154 	* 3 "Fan Speed Cruise" mode
158 pwm[1-7]_mode
159     - controls if output is PWM or DC level
165 -----------------------------
167 pwm[1-7]_temp_sel
171 pwm[1-7]_weight_temp_sel
179 pwm[1-7]_weight_duty_step
182 pwm[1-7]_weight_temp_step
187 pwm[1-7]_weight_temp_step_base
191 pwm[1-7]_weight_temp_step_tol
195 -----------------------
199 pwm[1-7]_target_temp
201 			(range 0 - 127000)
203 pwm[1-7]_temp_tolerance
206 There are no changes to fan speed. Once the temperature leaves the interval, fan
207 speed increases (if temperature is higher that desired) or decreases (if
211 pwm[1-7]_start
212 			fan pwm start value (range 1 - 255), to start fan
215 pwm[1-7]_floor
216 			lowest fan pwm (range 0 - 255) if temperature is below
220 pwm[1-7]_step_up_time
221 			milliseconds before fan speed is increased
223 pwm[1-7]_step_down_time
224 			milliseconds before fan speed is decreased
226 pwm[1-7]_stop_time
231 Speed Cruise mode (3)
232 ---------------------
234 This modes tries to keep the fan speed constant.
236 fan[1-7]_target
237 			Target fan speed
239 fan[1-7]_tolerance
240 			Target speed tolerance
246 ---------------------
248 This mode offers multiple slopes to control the fan speed. The slopes can be
254 critical temperature mode, in which the fans should run at full speed.
256 pwm[1-7]_auto_point[1-7]_pwm
260 pwm[1-7]_auto_point[1-7]_temp
263 pwm[1-7]_temp_tolerance
266 pwm[1-7]_crit_temp_tolerance
270 pwm[1-7]_step_up_time
271 			milliseconds before fan speed is increased
273 pwm[1-7]_step_down_time
274 			milliseconds before fan speed is decreased
277 -----------
280 connected to anything and floats, or that it is connected to some non-standard
284 temperature increases (similar to the raw PECI temperature value - see PECI
288 NCT6796D-S and NCT6799D-R chips are very similar and their chip_id indicates