==================
Supported chips:
+
* National Semiconductor LM93
+
Prefix 'lm93'
+
Addresses scanned: I2C 0x2c-0x2e
+
Datasheet: http://www.national.com/ds.cgi/LM/LM93.pdf
+
* National Semiconductor LM94
+
Prefix 'lm94'
+
Addresses scanned: I2C 0x2c-0x2e
+
Datasheet: http://www.national.com/ds.cgi/LM/LM94.pdf
+
Authors:
- Mark M. Hoffman <mhoffman@lightlink.com>
- Ported to 2.6 by Eric J. Bowersox <ericb@aspsys.com>
- Adapted to 2.6.20 by Carsten Emde <ce@osadl.org>
- Modified for mainline integration by Hans J. Koch <hjk@hansjkoch.de>
+ - Mark M. Hoffman <mhoffman@lightlink.com>
+ - Ported to 2.6 by Eric J. Bowersox <ericb@aspsys.com>
+ - Adapted to 2.6.20 by Carsten Emde <ce@osadl.org>
+ - Modified for mainline integration by Hans J. Koch <hjk@hansjkoch.de>
Module Parameters
-----------------
User Interface
--------------
-#PROCHOT:
+#PROCHOT
+^^^^^^^^
The LM93 can monitor two #PROCHOT signals. The results are found in the
sysfs files prochot1, prochot2, prochot1_avg, prochot2_avg, prochot1_max,
list will cause the driver to use the next largest interval. The available
intervals are (in seconds):
-#PROCHOT intervals: 0.73, 1.46, 2.9, 5.8, 11.7, 23.3, 46.6, 93.2, 186, 372
+#PROCHOT intervals:
+ 0.73, 1.46, 2.9, 5.8, 11.7, 23.3, 46.6, 93.2, 186, 372
It is possible to configure the LM93 to logically short the two #PROCHOT
signals. I.e. when #P1_PROCHOT is asserted, the LM93 will automatically
the override function is enabled. This value ranges from 0 to 15, with 0
indicating minimum duty cycle and 15 indicating maximum.
-#VRD_HOT:
+#VRD_HOT
+^^^^^^^^
The LM93 can monitor two #VRD_HOT signals. The results are found in the
sysfs files vrdhot1 and vrdhot2. There is one value per file: a boolean for
which 1 indicates #VRD_HOT is asserted and 0 indicates it is negated. These
files are read-only.
-Smart Tach Mode:
-
-(from the datasheet)
+Smart Tach Mode (from the datasheet)::
If a fan is driven using a low-side drive PWM, the tachometer
output of the fan is corrupted. The LM93 includes smart tachometer
will disable the function for that fan. Note that Smart tach mode cannot be
enabled if the PWM output frequency is 22500 Hz (see below).
-Manual PWM:
+Manual PWM
+^^^^^^^^^^
The LM93 has a fixed or override mode for the two PWM outputs (although, there
are still some conditions that will override even this mode - see section
PWM mode is disabled, the value of pwm1 and pwm2 indicates the current duty
cycle chosen by the h/w.
-PWM Output Frequency:
+PWM Output Frequency
+^^^^^^^^^^^^^^^^^^^^
The LM93 supports several different frequencies for the PWM output channels.
The sysfs files pwm1_freq and pwm2_freq are used to select the frequency. The
not available will cause the driver to use the next largest value. Also note
that this parameter has implications for the Smart Tach Mode (see above).
-PWM Output Frequencies (in Hz): 12, 36, 48, 60, 72, 84, 96, 22500 (default)
+PWM Output Frequencies (in Hz):
+ 12, 36, 48, 60, 72, 84, 96, 22500 (default)
-Automatic PWM:
+Automatic PWM
+^^^^^^^^^^^^^
The LM93 is capable of complex automatic fan control, with many different
points of configuration. To start, each PWM output can be bound to any
in the sysfs files pwm<n>_auto_channels, where a "1" enables the binding, and
a "0" disables it. The h/w default is 0x0f (all temperatures bound).
- 0x01 - Temp 1
- 0x02 - Temp 2
- 0x04 - Temp 3
- 0x08 - Temp 4
- 0x10 - #PROCHOT 1
- 0x20 - #PROCHOT 2
- 0x40 - #VRDHOT 1
- 0x80 - #VRDHOT 2
+ ====== ===========
+ 0x01 Temp 1
+ 0x02 Temp 2
+ 0x04 Temp 3
+ 0x08 Temp 4
+ 0x10 #PROCHOT 1
+ 0x20 #PROCHOT 2
+ 0x40 #VRDHOT 1
+ 0x80 #VRDHOT 2
+ ====== ===========
The function y = f(x) takes a source temperature x to a PWM output y. This
function of the LM93 is derived from a base temperature and a table of 12
contained in the file temp<n>_auto_offset<i>. E.g. if the base temperature
is 40C:
+ ========== ======================= =============== =======
offset # temp<n>_auto_offset<i> range pwm
+ ========== ======================= =============== =======
1 0 - 25.00%
2 0 - 28.57%
3 1 40C - 41C 32.14%
10 2 54C - 56C 57.14%
11 2 56C - 58C 71.43%
12 2 58C - 60C 85.71%
- > 60C 100.00%
+ - - > 60C 100.00%
+ ========== ======================= =============== =======
Valid offsets are in the range 0C <= x <= 7.5C in 0.5C increments.
and temp[34]. Therefore, any change to e.g. temp1_auto_pwm_min will also
affect temp2_auto_pwm_min.
-PWM Spin-Up Cycle:
+PWM Spin-Up Cycle
+^^^^^^^^^^^^^^^^^
A spin-up cycle occurs when a PWM output is commanded from 0% duty cycle to
some value > 0%. The LM93 supports a minimum duty cycle during spin-up. These
the hardware. Selecting a value which is not available will cause the driver
to use the next largest value.
-Spin-up Durations: 0 (disabled, h/w default), 0.1, 0.25, 0.4, 0.7, 1.0,
- 2.0, 4.0
+Spin-up Durations:
+ 0 (disabled, h/w default), 0.1, 0.25, 0.4, 0.7, 1.0, 2.0, 4.0
-#PROCHOT and #VRDHOT PWM Ramping:
+#PROCHOT and #VRDHOT PWM Ramping
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
If the #PROCHOT or #VRDHOT signals are asserted while bound to a PWM output
channel, the LM93 will ramp the PWM output up to 100% duty cycle in discrete
The available ramp times are constrained by the hardware. Selecting a value
which is not available will cause the driver to use the next largest value.
-Ramp Times: 0 (disabled, h/w default) to 0.75 in 0.05 second intervals
+Ramp Times:
+ 0 (disabled, h/w default) to 0.75 in 0.05 second intervals
-Fan Boost:
+Fan Boost
+^^^^^^^^^
For each temperature channel, there is a boost temperature: if the channel
exceeds this limit, the LM93 will immediately drive both PWM outputs to 100%.
the boost function is disabled. This temperature is also expressed in degrees
C in the sysfs files temp<n>_auto_boost_hyst.
-GPIO Pins:
+GPIO Pins
+^^^^^^^^^
The LM93 can monitor the logic level of four dedicated GPIO pins as well as the
four tach input pins. GPIO0-GPIO3 correspond to (fan) tach 1-4, respectively.
LM93 Unique sysfs Files
-----------------------
- file description
- -------------------------------------------------------------
-
- prochot<n> current #PROCHOT %
-
- prochot<n>_avg moving average #PROCHOT %
-
- prochot<n>_max limit #PROCHOT %
-
- prochot_short enable or disable logical #PROCHOT pin short
-
- prochot<n>_override force #PROCHOT assertion as PWM
-
- prochot_override_duty_cycle
- duty cycle for the PWM signal used when
- #PROCHOT is overridden
-
- prochot<n>_interval #PROCHOT PWM sampling interval
-
- vrdhot<n> 0 means negated, 1 means asserted
-
- fan<n>_smart_tach enable or disable smart tach mode
-
- pwm<n>_auto_channels select control sources for PWM outputs
-
- pwm<n>_auto_spinup_min minimum duty cycle during spin-up
-
- pwm<n>_auto_spinup_time duration of spin-up
-
- pwm_auto_prochot_ramp ramp time per step when #PROCHOT asserted
-
- pwm_auto_vrdhot_ramp ramp time per step when #VRDHOT asserted
-
- temp<n>_auto_base temperature channel base
-
- temp<n>_auto_offset[1-12]
- temperature channel offsets
-
- temp<n>_auto_offset_hyst
- temperature channel offset hysteresis
-
- temp<n>_auto_boost temperature channel boost (PWMs to 100%) limit
-
- temp<n>_auto_boost_hyst temperature channel boost hysteresis
-
- gpio input state of 8 GPIO pins; read-only
-
+=========================== ===============================================
+file description
+=========================== ===============================================
+prochot<n> current #PROCHOT %
+prochot<n>_avg moving average #PROCHOT %
+prochot<n>_max limit #PROCHOT %
+prochot_short enable or disable logical #PROCHOT pin short
+prochot<n>_override force #PROCHOT assertion as PWM
+prochot_override_duty_cycle duty cycle for the PWM signal used when
+ #PROCHOT is overridden
+prochot<n>_interval #PROCHOT PWM sampling interval
+vrdhot<n> 0 means negated, 1 means asserted
+fan<n>_smart_tach enable or disable smart tach mode
+pwm<n>_auto_channels select control sources for PWM outputs
+pwm<n>_auto_spinup_min minimum duty cycle during spin-up
+pwm<n>_auto_spinup_time duration of spin-up
+pwm_auto_prochot_ramp ramp time per step when #PROCHOT asserted
+pwm_auto_vrdhot_ramp ramp time per step when #VRDHOT asserted
+temp<n>_auto_base temperature channel base
+temp<n>_auto_offset[1-12] temperature channel offsets
+temp<n>_auto_offset_hyst temperature channel offset hysteresis
+temp<n>_auto_boost temperature channel boost (PWMs to 100%)
+ limit
+temp<n>_auto_boost_hyst temperature channel boost hysteresis
+gpio input state of 8 GPIO pins; read-only
+=========================== ===============================================
projects / mirror_ubuntu-jammy-kernel.git / blobdiff