[PATCH] hwmon: Sysfs interface documentation update, 1 of 2

This patch cleans up hwmon sysfs documentation file, plus introduces
the description of DC/PWM selection for fan speed control.

Signed-off-by: Rudolf Marek <r.marek@sh.cvut.cz>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 107 insertions, 74 deletions

diff --git a/Documentation/hwmon/sysfs-interface b/Documentation/hwmon/sysfs-interface
index eeb912254db..bc59a5113d1 100644
--- a/Documentation/hwmon/sysfs-interface
+++ b/Documentation/hwmon/sysfs-interface
@@ -69,28 +69,37 @@ to cause an alarm) is chip-dependent.
 
 -------------------------------------------------------------------------
 
+[0-*]   denotes any positive number starting from 0
+[1-*]   denotes any positive number starting from 1
+RO      read only value
+RW      read/write value
+
+Read/write values may be read-only for some chips, depending on the
+hardware implementation.
+
 ************
 * Voltages *
 ************
 
-in[0-8]_min     Voltage min value.
+in[0-*]_min     Voltage min value.
                 Unit: millivolt
-                Read/Write
+                RW
                 
-in[0-8]_max     Voltage max value.
+in[0-*]_max     Voltage max value.
                 Unit: millivolt
-                Read/Write
+                RW
                 
-in[0-8]_input   Voltage input value.
+in[0-*]_input   Voltage input value.
                 Unit: millivolt
-                Read only
+                RO
+                Voltage measured on the chip pin.
                 Actual voltage depends on the scaling resistors on the
                 motherboard, as recommended in the chip datasheet.
                 This varies by chip and by motherboard.
                 Because of this variation, values are generally NOT scaled
                 by the chip driver, and must be done by the application.
                 However, some drivers (notably lm87 and via686a)
-                do scale, with various degrees of success.
+                do scale, because of internal resistors built into a chip.
                 These drivers will output the actual voltage.
 
                 Typical usage:
@@ -104,58 +113,72 @@ in[0-8]_input	Voltage input value.
                         in7_*   varies
                         in8_*   varies
 
-cpu[0-1]_vid    CPU core reference voltage.
+cpu[0-*]_vid    CPU core reference voltage.
                 Unit: millivolt
-                Read only.
+                RO
                 Not always correct.
 
 vrm             Voltage Regulator Module version number. 
-                Read only.
-                Two digit number, first is major version, second is
-                minor version.
+                RW (but changing it should no more be necessary)
+                Originally the VRM standard version multiplied by 10, but now
+                an arbitrary number, as not all standards have a version
+                number.
                 Affects the way the driver calculates the CPU core reference
                 voltage from the vid pins.
 
+Also see the Alarms section for status flags associated with voltages.
+
 
 ********
 * Fans *
 ********
 
-fan[1-3]_min    Fan minimum value
+fan[1-*]_min    Fan minimum value
                 Unit: revolution/min (RPM)
-                Read/Write.
+                RW
 
-fan[1-3]_input  Fan input value.
+fan[1-*]_input  Fan input value.
                 Unit: revolution/min (RPM)
-                Read only.
+                RO
 
-fan[1-3]_div    Fan divisor.
+fan[1-*]_div    Fan divisor.
                 Integer value in powers of two (1, 2, 4, 8, 16, 32, 64, 128).
+                RW
                 Some chips only support values 1, 2, 4 and 8.
                 Note that this is actually an internal clock divisor, which
                 affects the measurable speed range, not the read value.
 
+Also see the Alarms section for status flags associated with fans.
+
+
 *******
 * PWM *
 *******
 
-pwm[1-3]        Pulse width modulation fan control.
+pwm[1-*]        Pulse width modulation fan control.
                 Integer value in the range 0 to 255
-                Read/Write
+                RW
                 255 is max or 100%.
 
-pwm[1-3]_enable
+pwm[1-*]_enable
                 Switch PWM on and off.
                 Not always present even if fan*_pwm is.
-                0 to turn off
-                1 to turn on in manual mode
-                2 to turn on in automatic mode
-                Read/Write
+                0: turn off
+                1: turn on in manual mode
+                2+: turn on in automatic mode
+                Check individual chip documentation files for automatic mode details.
+                RW
+
+pwm[1-*]_mode
+                0: DC mode
+                1: PWM mode
+                RW
 
 pwm[1-*]_auto_channels_temp
                 Select which temperature channels affect this PWM output in
                 auto mode. Bitfield, 1 is temp1, 2 is temp2, 4 is temp3 etc...
                 Which values are possible depend on the chip used.
+                RW
 
 pwm[1-*]_auto_point[1-*]_pwm
 pwm[1-*]_auto_point[1-*]_temp
@@ -163,6 +186,7 @@ pwm[1-*]_auto_point[1-*]_temp_hyst
                 Define the PWM vs temperature curve. Number of trip points is
                 chip-dependent. Use this for chips which associate trip points
                 to PWM output channels.
+                RW
 
 OR
 
@@ -172,51 +196,52 @@ temp[1-*]_auto_point[1-*]_temp_hyst
                 Define the PWM vs temperature curve. Number of trip points is
                 chip-dependent. Use this for chips which associate trip points
                 to temperature channels.
+                RW
 
 
 ****************
 * Temperatures *
 ****************
 
-temp[1-3]_type  Sensor type selection.
+temp[1-*]_type  Sensor type selection.
                 Integers 1 to 4 or thermistor Beta value (typically 3435)
-                Read/Write.
+                RW
                 1: PII/Celeron Diode
                 2: 3904 transistor
                 3: thermal diode
                 4: thermistor (default/unknown Beta)
                 Not all types are supported by all chips
 
-temp[1-4]_max   Temperature max value.
+temp[1-*]_max   Temperature max value.
                 Unit: millidegree Celcius
-                Read/Write value.
+                RW
 
-temp[1-3]_min   Temperature min value.
+temp[1-*]_min   Temperature min value.
                 Unit: millidegree Celcius
-                Read/Write value.
+                RW
 
-temp[1-3]_max_hyst
+temp[1-*]_max_hyst
                 Temperature hysteresis value for max limit.
                 Unit: millidegree Celcius
                 Must be reported as an absolute temperature, NOT a delta
                 from the max value.
-                Read/Write value.
+                RW
 
-temp[1-4]_input Temperature input value.
+temp[1-*]_input Temperature input value.
                 Unit: millidegree Celcius
-                Read only value.
+                RO
 
-temp[1-4]_crit  Temperature critical value, typically greater than
+temp[1-*]_crit  Temperature critical value, typically greater than
                 corresponding temp_max values.
                 Unit: millidegree Celcius
-                Read/Write value.
+                RW
 
-temp[1-2]_crit_hyst
+temp[1-*]_crit_hyst
                 Temperature hysteresis value for critical limit.
                 Unit: millidegree Celcius
                 Must be reported as an absolute temperature, NOT a delta
                 from the critical value.
-                Read/Write value.
+                RW
 
 temp[1-4]_offset
                 Temperature offset which is added to the temperature reading
@@ -231,6 +256,8 @@ temp[1-4]_offset
                 itself, for example the thermal diode inside the CPU or
                 a thermistor nearby.
 
+Also see the Alarms section for status flags associated with temperatures.
+
 
 ************
 * Currents *
@@ -239,17 +266,17 @@ temp[1-4]_offset
 Note that no known chip provides current measurements as of writing,
 so this part is theoretical, so to say.
 
-curr[1-n]_max   Current max value
+curr[1-*]_max   Current max value
                 Unit: milliampere
-                Read/Write.
+                RW
 
-curr[1-n]_min   Current min value.
+curr[1-*]_min   Current min value.
                 Unit: milliampere
-                Read/Write.
+                RW
 
-curr[1-n]_input Current input value
+curr[1-*]_input Current input value
                 Unit: milliampere
-                Read only.
+                RO
 
 
 **********
@@ -263,50 +290,54 @@ Usually a given chip will either use channel-related alarms, or
 limit-related alarms, not both. The driver should just reflect the hardware
 implementation.
 
-in[0-n]_alarm
-fan[1-n]_alarm
-temp[1-n]_alarm
+in[0-*]_alarm
+fan[1-*]_alarm
+temp[1-*]_alarm
                 Channel alarm
-                Boolean
-                Read-only
+                0: no alarm
+                1: alarm
+                RO
 
 OR
 
-in[0-n]_min_alarm
-in[0-n]_max_alarm
-fan[1-n]_min_alarm
-temp[1-n]_min_alarm
-temp[1-n]_max_alarm
-temp[1-n]_crit_alarm
+in[0-*]_min_alarm
+in[0-*]_max_alarm
+fan[1-*]_min_alarm
+temp[1-*]_min_alarm
+temp[1-*]_max_alarm
+temp[1-*]_crit_alarm
                 Limit alarm
-                Boolean
-                Read-only
+                0: no alarm
+                1: alarm
+                RO
 
 Each input channel may have an associated fault file. This can be used
 to notify open diodes, unconnected fans etc. where the hardware
 supports it. When this boolean has value 1, the measurement for that
 channel should not be trusted.
 
-in[0-n]_input_fault
-fan[1-n]_input_fault
-temp[1-n]_input_fault
+in[0-*]_input_fault
+fan[1-*]_input_fault
+temp[1-*]_input_fault
                 Input fault condition
-                Boolean
-                Read-only
+                0: no fault occured
+                1: fault condition
+                RO
 
 Some chips also offer the possibility to get beeped when an alarm occurs:
 
 beep_enable     Master beep enable
-                Boolean
-                Read/Write
+                0: no beeps
+                1: beeps
+                RW
 
-in[0-n]_beep
-fan[1-n]_beep
-temp[1-n]_beep
+in[0-*]_beep
+fan[1-*]_beep
+temp[1-*]_beep
                 Channel beep
-                0 to disable.
-                1 to enable.
-                Read/write
+                0: disable
+                1: enable
+                RW
 
 In theory, a chip could provide per-limit beep masking, but no such chip
 was seen so far.
@@ -316,7 +347,7 @@ beeps. These interface files are deprecated, but will be kept around
 for compatibility reasons:
 
 alarms          Alarm bitmask.
-                Read only.
+                RO
                 Integer representation of one to four bytes.
                 A '1' bit means an alarm.
                 Chips should be programmed for 'comparator' mode so that
@@ -333,7 +364,7 @@ beep_mask	Bitmask for beep.
                 Same format as 'alarms' with the same bit locations,
                 use discouraged for the same reason. Use individual
                 *_beep files instead.
-                Read/Write
+                RW
 
 
 *********
@@ -341,7 +372,9 @@ beep_mask	Bitmask for beep.
 *********
 
 eeprom          Raw EEPROM data in binary form.
-                Read only.
+                RO
 
 pec             Enable or disable PEC (SMBus only)
-                Read/Write
+                0: disable
+                1: enable
+                RW