Documentation/hwmon/asc7621 - kernel/mindspeed - Git at Google

 Kernel driver asc7621
 ==================

 Supported chips:
     Andigilog aSC7621 and aSC7621a
     Prefix: 'asc7621'
     Addresses scanned: I2C 0x2c, 0x2d, 0x2e
     Datasheet: http://www.fairview5.com/linux/asc7621/asc7621.pdf

 Author:
 		George Joseph

 Description provided by Dave Pivin @ Andigilog:

 Andigilog has both the PECI and pre-PECI versions of the Heceta-6, as
 Intel calls them. Heceta-6e has high frequency PWM and Heceta-6p has
 added PECI and a 4th thermal zone. The Andigilog aSC7611 is the
 Heceta-6e part and aSC7621 is the Heceta-6p part. They are both in
 volume production, shipping to Intel and their subs.

 We have enhanced both parts relative to the governing Intel
 specification. First enhancement is temperature reading resolution. We
 have used registers below 20h for vendor-specific functions in addition
 to those in the Intel-specified vendor range.

 Our conversion process produces a result that is reported as two bytes.
 The fan speed control uses this finer value to produce a "step-less" fan
 PWM output. These two bytes are "read-locked" to guarantee that once a
 high or low byte is read, the other byte is locked-in until after the
 next read of any register. So to get an atomic reading, read high or low
 byte, then the very next read should be the opposite byte. Our data
 sheet says 10-bits of resolution, although you may find the lower bits
 are active, they are not necessarily reliable or useful externally. We
 chose not to mask them.

 We employ significant filtering that is user tunable as described in the
 data sheet. Our temperature reports and fan PWM outputs are very smooth
 when compared to the competition, in addition to the higher resolution
 temperature reports. The smoother PWM output does not require user
 intervention.

 We offer GPIO features on the former VID pins. These are open-drain
 outputs or inputs and may be used as general purpose I/O or as alarm
 outputs that are based on temperature limits. These are in 19h and 1Ah.

 We offer flexible mapping of temperature readings to thermal zones. Any
 temperature may be mapped to any zone, which has a default assignment
 that follows Intel's specs.

 Since there is a fan to zone assignment that allows for the "hotter" of
 a set of zones to control the PWM of an individual fan, but there is no
 indication to the user, we have added an indicator that shows which zone
 is currently controlling the PWM for a given fan. This is in register
 00h.

 Both remote diode temperature readings may be given an offset value such
 that the reported reading as well as the temperature used to determine
 PWM may be offset for system calibration purposes.

 PECI Extended configuration allows for having more than two domains per
 PECI address and also provides an enabling function for each PECI
 address. One could use our flexible zone assignment to have a zone
 assigned to up to 4 PECI addresses. This is not possible in the default
 Intel configuration. This would be useful in multi-CPU systems with
 individual fans on each that would benefit from individual fan control.
 This is in register 0Eh.

 The tachometer measurement system is flexible and able to adapt to many
 fan types. We can also support pulse-stretched PWM so that 3-wire fans
 may be used. These characteristics are in registers 04h to 07h.

 Finally, we have added a tach disable function that turns off the tach
 measurement system for individual tachs in order to save power. That is
 in register 75h.

 --
 aSC7621 Product Description

 The aSC7621 has a two wire digital interface compatible with SMBus 2.0.
 Using a 10-bit ADC, the aSC7621 measures the temperature of two remote diode
 connected transistors as well as its own die. Support for Platform
 Environmental Control Interface (PECI) is included.

 Using temperature information from these four zones, an automatic fan speed
 control algorithm is employed to minimize acoustic impact while achieving
 recommended CPU temperature under varying operational loads.

 To set fan speed, the aSC7621 has three independent pulse width modulation
 (PWM) outputs that are controlled by one, or a combination of three,
 temperature zones. Both high- and low-frequency PWM ranges are supported.

 The aSC7621 also includes a digital filter that can be invoked to smooth
 temperature readings for better control of fan speed and minimum acoustic
 impact.

 The aSC7621 has tachometer inputs to measure fan speed on up to four fans.
 Limit and status registers for all measured values are included to alert
 the system host that any measurements are outside of programmed limits
 via status registers.

 System voltages of VCCP, 2.5V, 3.3V, 5.0V, and 12V motherboard power are
 monitored efficiently with internal scaling resistors.

 Features
 - Supports PECI interface and monitors internal and remote thermal diodes
 - 2-wire, SMBus 2.0 compliant, serial interface
 - 10-bit ADC
 - Monitors VCCP, 2.5V, 3.3V, 5.0V, and 12V motherboard/processor supplies
 - Programmable autonomous fan control based on temperature readings
 - Noise filtering of temperature reading for fan speed control
 - 0.25C digital temperature sensor resolution
 - 3 PWM fan speed control outputs for 2-, 3- or 4-wire fans and up to 4 fan
 	tachometer inputs
 - Enhanced measured temperature to Temperature Zone assignment.
 - Provides high and low PWM frequency ranges
 - 3 GPIO pins for custom use
 - 24-Lead QSOP package

 Configuration Notes
 ===================

 Except where noted below, the sysfs entries created by this driver follow
 the standards defined in "sysfs-interface".

 temp1_source
 	0 	(default) peci_legacy = 0, Remote 1 Temperature
 			peci_legacy = 1, PECI Processor Temperature 0
 	1 	Remote 1 Temperature
 	2 	Remote 2 Temperature
 	3 	Internal Temperature
 	4 	PECI Processor Temperature 0
 	5 	PECI Processor Temperature 1
 	6 	PECI Processor Temperature 2
 	7  PECI Processor Temperature 3

 temp2_source
 	0 	(default) Internal Temperature
 	1 	Remote 1 Temperature
 	2 	Remote 2 Temperature
 	3 	Internal Temperature
 	4 	PECI Processor Temperature 0
 	5 	PECI Processor Temperature 1
 	6 	PECI Processor Temperature 2
 	7 	PECI Processor Temperature 3

 temp3_source
 	0 	(default) Remote 2 Temperature
 	1 	Remote 1 Temperature
 	2 	Remote 2 Temperature
 	3 	Internal Temperature
 	4 	PECI Processor Temperature 0
 	5 	PECI Processor Temperature 1
 	6 	PECI Processor Temperature 2
 	7 	PECI Processor Temperature 3

 temp4_source
 	0 	(default) peci_legacy = 0, PECI Processor Temperature 0
 			peci_legacy = 1, Remote 1 Temperature
 	1 	Remote 1 Temperature
 	2 	Remote 2 Temperature
 	3 	Internal Temperature
 	4 	PECI Processor Temperature 0
 	5 	PECI Processor Temperature 1
 	6 	PECI Processor Temperature 2
 	7 	PECI Processor Temperature 3

 temp[1-4]_smoothing_enable
 temp[1-4]_smoothing_time
 	Smooths spikes in temp readings caused by noise.
 	Valid values in milliseconds are:
 	35000
 	17600
 	11800
 	 7000
 	 4400
 	 3000
 	 1600
 	  800

 temp[1-4]_crit
 	When the corresponding zone temperature reaches this value,
 	ALL pwm outputs will got to 100%.

 temp[5-8]_input
 temp[5-8]_enable
 	The aSC7621 can also read temperatures provided by the processor
 	via the PECI bus.  Usually these are "core" temps and are relative
 	to the point where the automatic thermal control circuit starts
 	throttling.  This means that these are usually negative numbers.

 pwm[1-3]_enable
 	0		Fan off.
 	1		Fan on manual control.
 	2		Fan on automatic control and will run at the minimum pwm
 				if the temperature for the zone is below the minimum.
 	3		Fan on automatic control but will be off if the temperature
 				for the zone is below the minimum.
 	4-254	Ignored.
 	255		Fan on full.

 pwm[1-3]_auto_channels
 	Bitmap as described in sysctl-interface with the following
 	exceptions...
 	Only the following combination of zones (and their corresponding masks)
 	are valid:
 	1
 	2
 	3
 	2,3
 	1,2,3
 	4
 	1,2,3,4

 	Special values:
 	0			Disabled.
 	16		Fan on manual control.
 	31		Fan on full.


 pwm[1-3]_invert
 	When set, inverts the meaning of pwm[1-3].
 	i.e.  when pwm = 0, the fan will be on full and
 	when pwm = 255 the fan will be off.

 pwm[1-3]_freq
 	PWM frequency in Hz
 	Valid values in Hz are:

 	10
 	15
 	23
 	30  (default)
 	38
 	47
 	62
 	94
 	23000
 	24000
 	25000
 	26000
 	27000
 	28000
 	29000
 	30000

 	Setting any other value will be ignored.

 peci_enable
 	Enables or disables PECI

 peci_avg
 	Input filter average time.

 	0 	0 Sec. (no Smoothing) (default)
 	1 	0.25 Sec.
 	2 	0.5 Sec.
 	3 	1.0 Sec.
 	4 	2.0 Sec.
 	5 	4.0 Sec.
 	6 	8.0 Sec.
 	7 	0.0 Sec.

 peci_legacy

 	0	Standard Mode (default)
 		Remote Diode 1 reading is associated with
 		Temperature Zone 1, PECI is associated with
 		Zone 4

 	1	Legacy Mode
 		PECI is associated with Temperature Zone 1,
 		Remote Diode 1 is associated with Zone 4

 peci_diode
 	Diode filter

 	0	0.25 Sec.
 	1 	1.1 Sec.
 	2 	2.4 Sec.  (default)
 	3 	3.4 Sec.
 	4 	5.0 Sec.
 	5 	6.8 Sec.
 	6 	10.2 Sec.
 	7 	16.4 Sec.

 peci_4domain
 	Four domain enable

 	0 	1 or 2 Domains for enabled processors (default)
 	1 	3 or 4 Domains for enabled processors

 peci_domain
 	Domain

 	0 	Processor contains a single domain (0) 	 (default)
 	1 	Processor contains two domains (0,1)
	Kernel driver asc7621
	==================

	Supported chips:
	Andigilog aSC7621 and aSC7621a
	Prefix: 'asc7621'
	Addresses scanned: I2C 0x2c, 0x2d, 0x2e
	Datasheet: http://www.fairview5.com/linux/asc7621/asc7621.pdf

	Author:
	George Joseph

	Description provided by Dave Pivin @ Andigilog:

	Andigilog has both the PECI and pre-PECI versions of the Heceta-6, as
	Intel calls them. Heceta-6e has high frequency PWM and Heceta-6p has
	added PECI and a 4th thermal zone. The Andigilog aSC7611 is the
	Heceta-6e part and aSC7621 is the Heceta-6p part. They are both in
	volume production, shipping to Intel and their subs.

	We have enhanced both parts relative to the governing Intel
	specification. First enhancement is temperature reading resolution. We
	have used registers below 20h for vendor-specific functions in addition
	to those in the Intel-specified vendor range.

	Our conversion process produces a result that is reported as two bytes.
	The fan speed control uses this finer value to produce a "step-less" fan
	PWM output. These two bytes are "read-locked" to guarantee that once a
	high or low byte is read, the other byte is locked-in until after the
	next read of any register. So to get an atomic reading, read high or low
	byte, then the very next read should be the opposite byte. Our data
	sheet says 10-bits of resolution, although you may find the lower bits
	are active, they are not necessarily reliable or useful externally. We
	chose not to mask them.

	We employ significant filtering that is user tunable as described in the
	data sheet. Our temperature reports and fan PWM outputs are very smooth
	when compared to the competition, in addition to the higher resolution
	temperature reports. The smoother PWM output does not require user
	intervention.

	We offer GPIO features on the former VID pins. These are open-drain
	outputs or inputs and may be used as general purpose I/O or as alarm
	outputs that are based on temperature limits. These are in 19h and 1Ah.

	We offer flexible mapping of temperature readings to thermal zones. Any
	temperature may be mapped to any zone, which has a default assignment
	that follows Intel's specs.

	Since there is a fan to zone assignment that allows for the "hotter" of
	a set of zones to control the PWM of an individual fan, but there is no
	indication to the user, we have added an indicator that shows which zone
	is currently controlling the PWM for a given fan. This is in register
	00h.

	Both remote diode temperature readings may be given an offset value such
	that the reported reading as well as the temperature used to determine
	PWM may be offset for system calibration purposes.

	PECI Extended configuration allows for having more than two domains per
	PECI address and also provides an enabling function for each PECI
	address. One could use our flexible zone assignment to have a zone
	assigned to up to 4 PECI addresses. This is not possible in the default
	Intel configuration. This would be useful in multi-CPU systems with
	individual fans on each that would benefit from individual fan control.
	This is in register 0Eh.

	The tachometer measurement system is flexible and able to adapt to many
	fan types. We can also support pulse-stretched PWM so that 3-wire fans
	may be used. These characteristics are in registers 04h to 07h.

	Finally, we have added a tach disable function that turns off the tach
	measurement system for individual tachs in order to save power. That is
	in register 75h.

	--
	aSC7621 Product Description

	The aSC7621 has a two wire digital interface compatible with SMBus 2.0.
	Using a 10-bit ADC, the aSC7621 measures the temperature of two remote diode
	connected transistors as well as its own die. Support for Platform
	Environmental Control Interface (PECI) is included.

	Using temperature information from these four zones, an automatic fan speed
	control algorithm is employed to minimize acoustic impact while achieving
	recommended CPU temperature under varying operational loads.

	To set fan speed, the aSC7621 has three independent pulse width modulation
	(PWM) outputs that are controlled by one, or a combination of three,
	temperature zones. Both high- and low-frequency PWM ranges are supported.

	The aSC7621 also includes a digital filter that can be invoked to smooth
	temperature readings for better control of fan speed and minimum acoustic
	impact.

	The aSC7621 has tachometer inputs to measure fan speed on up to four fans.
	Limit and status registers for all measured values are included to alert
	the system host that any measurements are outside of programmed limits
	via status registers.

	System voltages of VCCP, 2.5V, 3.3V, 5.0V, and 12V motherboard power are
	monitored efficiently with internal scaling resistors.

	Features
	- Supports PECI interface and monitors internal and remote thermal diodes
	- 2-wire, SMBus 2.0 compliant, serial interface
	- 10-bit ADC
	- Monitors VCCP, 2.5V, 3.3V, 5.0V, and 12V motherboard/processor supplies
	- Programmable autonomous fan control based on temperature readings
	- Noise filtering of temperature reading for fan speed control
	- 0.25C digital temperature sensor resolution
	- 3 PWM fan speed control outputs for 2-, 3- or 4-wire fans and up to 4 fan
	tachometer inputs
	- Enhanced measured temperature to Temperature Zone assignment.
	- Provides high and low PWM frequency ranges
	- 3 GPIO pins for custom use
	- 24-Lead QSOP package

	Configuration Notes
	===================

	Except where noted below, the sysfs entries created by this driver follow
	the standards defined in "sysfs-interface".

	temp1_source
	0 (default) peci_legacy = 0, Remote 1 Temperature
	peci_legacy = 1, PECI Processor Temperature 0
	1 Remote 1 Temperature
	2 Remote 2 Temperature
	3 Internal Temperature
	4 PECI Processor Temperature 0
	5 PECI Processor Temperature 1
	6 PECI Processor Temperature 2
	7 PECI Processor Temperature 3

	temp2_source
	0 (default) Internal Temperature
	1 Remote 1 Temperature
	2 Remote 2 Temperature
	3 Internal Temperature
	4 PECI Processor Temperature 0
	5 PECI Processor Temperature 1
	6 PECI Processor Temperature 2
	7 PECI Processor Temperature 3

	temp3_source
	0 (default) Remote 2 Temperature
	1 Remote 1 Temperature
	2 Remote 2 Temperature
	3 Internal Temperature
	4 PECI Processor Temperature 0
	5 PECI Processor Temperature 1
	6 PECI Processor Temperature 2
	7 PECI Processor Temperature 3

	temp4_source
	0 (default) peci_legacy = 0, PECI Processor Temperature 0
	peci_legacy = 1, Remote 1 Temperature
	1 Remote 1 Temperature
	2 Remote 2 Temperature
	3 Internal Temperature
	4 PECI Processor Temperature 0
	5 PECI Processor Temperature 1
	6 PECI Processor Temperature 2
	7 PECI Processor Temperature 3

	temp[1-4]_smoothing_enable
	temp[1-4]_smoothing_time
	Smooths spikes in temp readings caused by noise.
	Valid values in milliseconds are:
	35000
	17600
	11800
	7000
	4400
	3000
	1600
	800

	temp[1-4]_crit
	When the corresponding zone temperature reaches this value,
	ALL pwm outputs will got to 100%.

	temp[5-8]_input
	temp[5-8]_enable
	The aSC7621 can also read temperatures provided by the processor
	via the PECI bus. Usually these are "core" temps and are relative
	to the point where the automatic thermal control circuit starts
	throttling. This means that these are usually negative numbers.

	pwm[1-3]_enable
	0 Fan off.
	1 Fan on manual control.
	2 Fan on automatic control and will run at the minimum pwm
	if the temperature for the zone is below the minimum.
	3 Fan on automatic control but will be off if the temperature
	for the zone is below the minimum.
	4-254 Ignored.
	255 Fan on full.

	pwm[1-3]_auto_channels
	Bitmap as described in sysctl-interface with the following
	exceptions...
	Only the following combination of zones (and their corresponding masks)
	are valid:
	1
	2
	3
	2,3
	1,2,3
	4
	1,2,3,4

	Special values:
	0 Disabled.
	16 Fan on manual control.
	31 Fan on full.


	pwm[1-3]_invert
	When set, inverts the meaning of pwm[1-3].
	i.e. when pwm = 0, the fan will be on full and
	when pwm = 255 the fan will be off.

	pwm[1-3]_freq
	PWM frequency in Hz
	Valid values in Hz are:

	10
	15
	23
	30 (default)
	38
	47
	62
	94
	23000
	24000
	25000
	26000
	27000
	28000
	29000
	30000

	Setting any other value will be ignored.

	peci_enable
	Enables or disables PECI

	peci_avg
	Input filter average time.

	0 0 Sec. (no Smoothing) (default)
	1 0.25 Sec.
	2 0.5 Sec.
	3 1.0 Sec.
	4 2.0 Sec.
	5 4.0 Sec.
	6 8.0 Sec.
	7 0.0 Sec.

	peci_legacy

	0 Standard Mode (default)
	Remote Diode 1 reading is associated with
	Temperature Zone 1, PECI is associated with
	Zone 4

	1 Legacy Mode
	PECI is associated with Temperature Zone 1,
	Remote Diode 1 is associated with Zone 4

	peci_diode
	Diode filter

	0 0.25 Sec.
	1 1.1 Sec.
	2 2.4 Sec. (default)
	3 3.4 Sec.
	4 5.0 Sec.
	5 6.8 Sec.
	6 10.2 Sec.
	7 16.4 Sec.

	peci_4domain
	Four domain enable

	0 1 or 2 Domains for enabled processors (default)
	1 3 or 4 Domains for enabled processors

	peci_domain
	Domain

	0 Processor contains a single domain (0) (default)
	1 Processor contains two domains (0,1)