Merge branch 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging

    Prefix: 'it8720'

    Addresses scanned: from Super I/O config space (8 I/O ports)

    Datasheet: Not publicly available

  * IT8721F/IT8758E

    Prefix: 'it8721'

    Addresses scanned: from Super I/O config space (8 I/O ports)

    Datasheet: Not publicly available

  * SiS950   [clone of IT8705F]

    Prefix: 'it87'

    Addresses scanned: from Super I/O config space (8 I/O ports)

-----------

This driver implements support for the IT8705F, IT8712F, IT8716F,

IT8718F, IT8720F, IT8726F and SiS950 chips.

IT8718F, IT8720F, IT8721F, IT8726F, IT8758E and SiS950 chips.

These chips are 'Super I/O chips', supporting floppy disks, infrared ports,

joysticks and other miscellaneous stuff. For hardware monitoring, they

upper VID bits share their pins with voltage inputs (in5 and in6) so you

can't have both on a given board.

The IT8716F, IT8718F, IT8720F and later IT8712F revisions have support for

2 additional fans. The additional fans are supported by the driver.

The IT8716F, IT8718F, IT8720F, IT8721F/IT8758E and later IT8712F revisions

have support for 2 additional fans. The additional fans are supported by the

driver.

The IT8716F, IT8718F and IT8720F, and late IT8712F and IT8705F also have

optional 16-bit tachometer counters for fans 1 to 3. This is better (no more

fan clock divider mess) but not compatible with the older chips and

revisions. The 16-bit tachometer mode is enabled by the driver when one

of the above chips is detected.

The IT8716F, IT8718F, IT8720F and IT8721F/IT8758E, and late IT8712F and

IT8705F also have optional 16-bit tachometer counters for fans 1 to 3. This

is better (no more fan clock divider mess) but not compatible with the older

chips and revisions. The 16-bit tachometer mode is enabled by the driver when

one of the above chips is detected.

The IT8726F is just bit enhanced IT8716F with additional hardware

for AMD power sequencing. Therefore the chip will appear as IT8716F

maximum limit. Note that minimum in this case always means 'closest to

zero'; this is important for negative voltage measurements. All voltage

inputs can measure voltages between 0 and 4.08 volts, with a resolution of

0.016 volt. The battery voltage in8 does not have limit registers.

0.016 volt (except IT8721F/IT8758E: 0.012 volt.) The battery voltage in8 does

not have limit registers.

On the IT8721F/IT8758E, some voltage inputs are internal and scaled inside

the chip (in7, in8 and optionally in3). The driver handles this transparently

so user-space doesn't have to care.

The VID lines (IT8712F/IT8716F/IT8718F/IT8720F) encode the core voltage value:

the voltage level your processor should work with. This is hardcoded by

    Prefix: 'adt7463'

    Addresses scanned: I2C 0x2c, 0x2d, 0x2e

    Datasheet: http://www.onsemi.com/PowerSolutions/product.do?id=ADT7463

  * Analog Devices ADT7468

    Prefix: 'adt7468'

    Addresses scanned: I2C 0x2c, 0x2d, 0x2e

    Datasheet: http://www.onsemi.com/PowerSolutions/product.do?id=ADT7468

  * SMSC EMC6D100, SMSC EMC6D101

    Prefix: 'emc6d100'

    Addresses scanned: I2C 0x2c, 0x2d, 0x2e

-----------

This driver implements support for the National Semiconductor LM85 and

compatible chips including the Analog Devices ADM1027, ADT7463 and

compatible chips including the Analog Devices ADM1027, ADT7463, ADT7468 and

SMSC EMC6D10x chips family.

The LM85 uses the 2-wire interface compatible with the SMBUS 2.0

optional filter for smoothing temperatures. The ADM1027 has the same

config option but uses it to rate limit the changes to fan speed instead.

The ADM1027 and ADT7463 have a 10-bit ADC and can therefore measure

temperatures with 0.25 degC resolution. They also provide an offset to the

temperature readings that is automatically applied during measurement.

This offset can be used to zero out any errors due to traces and placement.

The documentation says that the offset is in 0.25 degC steps, but in

initial testing of the ADM1027 it was 1.00 degC steps. Analog Devices has

confirmed this "bug". The ADT7463 is reported to work as described in the

documentation. The current lm85 driver does not show the offset register.

The ADM1027, ADT7463 and ADT7468 have a 10-bit ADC and can therefore

measure temperatures with 0.25 degC resolution. They also provide an offset

to the temperature readings that is automatically applied during

measurement. This offset can be used to zero out any errors due to traces

and placement. The documentation says that the offset is in 0.25 degC

steps, but in initial testing of the ADM1027 it was 1.00 degC steps. Analog

Devices has confirmed this "bug". The ADT7463 is reported to work as

described in the documentation. The current lm85 driver does not show the

offset register.

The ADT7468 has a high-frequency PWM mode, where all PWM outputs are

driven by a 22.5 kHz clock. This is a global mode, not per-PWM output,

which means that setting any PWM frequency above 11.3 kHz will switch

all 3 PWM outputs to a 22.5 kHz frequency. Conversely, setting any PWM

frequency below 11.3 kHz will switch all 3 PWM outputs to a frequency

between 10 and 100 Hz, which can then be tuned separately.

See the vendor datasheets for more information. There is application note

from National (AN-1260) with some additional information about the LM85.

identifying the chip, the driver behaves no differently with regard to

these two chips. The LM85B is recommended for new designs.

The ADM1027 and ADT7463 chips have an optional SMBALERT output that can be

used to signal the chipset in case a limit is exceeded or the temperature

sensors fail. Individual sensor interrupts can be masked so they won't

trigger SMBALERT. The SMBALERT output if configured replaces one of the other

functions (PWM2 or IN0). This functionality is not implemented in current

driver.

The ADM1027, ADT7463 and ADT7468 chips have an optional SMBALERT output

that can be used to signal the chipset in case a limit is exceeded or the

temperature sensors fail. Individual sensor interrupts can be masked so

they won't trigger SMBALERT. The SMBALERT output if configured replaces one

of the other functions (PWM2 or IN0). This functionality is not implemented

in current driver.

The ADT7463 also has an optional THERM output/input which can be connected

to the processor PROC_HOT output. If available, the autofan control

dynamic Tmin feature can be enabled to keep the system temperature within

spec (just?!) with the least possible fan noise.

The ADT7463 and ADT7468 also have an optional THERM output/input which can

be connected to the processor PROC_HOT output. If available, the autofan

control dynamic Tmin feature can be enabled to keep the system temperature

within spec (just?!) with the least possible fan noise.

Configuration Notes

-------------------

measurements. These features are not currently supported by the lm85

driver.

In addition to the ADM1027 features, the ADT7463 also has Tmin control

and THERM asserted counts. Automatic Tmin control acts to adjust the

Tmin value to maintain the measured temperature sensor at a specified

temperature. There isn't much documentation on this feature in the

ADT7463 data sheet. This is not supported by current driver.

In addition to the ADM1027 features, the ADT7463 and ADT7468 also have

Tmin control and THERM asserted counts. Automatic Tmin control acts to

adjust the Tmin value to maintain the measured temperature sensor at a

specified temperature. There isn't much documentation on this feature in

the ADT7463 data sheet. This is not supported by current driver.

    Datasheet: Publicly available at the Maxim website

               http://www.maxim-ic.com/quick_view2.cfm/qv_pk/2578

  * Maxim MAX6659

    Prefix: 'max6657'

    Addresses scanned: I2C 0x4c, 0x4d (unsupported 0x4e)

    Prefix: 'max6659'

    Addresses scanned: I2C 0x4c, 0x4d, 0x4e

    Datasheet: Publicly available at the Maxim website

               http://www.maxim-ic.com/quick_view2.cfm/qv_pk/2578

  * Maxim MAX6680

    Addresses scanned: I2C 0x4c

    Datasheet: Publicly available at the Maxim website

               http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3500

  * Maxim MAX6695

    Prefix: 'max6695'

    Addresses scanned: I2C 0x18

    Datasheet: Publicly available at the Maxim website

               http://www.maxim-ic.com/datasheet/index.mvp/id/4199

  * Maxim MAX6696

    Prefix: 'max6695'

    Addresses scanned: I2C 0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b,

                           0x4c, 0x4d and 0x4e

    Datasheet: Publicly available at the Maxim website

               http://www.maxim-ic.com/datasheet/index.mvp/id/4199

  * Winbond/Nuvoton W83L771W/G

    Prefix: 'w83l771'

    Addresses scanned: I2C 0x4c

    Datasheet: No longer available

  * Winbond/Nuvoton W83L771AWG/ASG

    Prefix: 'w83l771'

    Addresses scanned: I2C 0x4c

with many other devices, many of which are supported by this driver.

Note that there is no easy way to differentiate between the MAX6657,

MAX6658 and MAX6659 variants. The extra address and features of the

MAX6659 are not supported by this driver. The MAX6680 and MAX6681 only

differ in their pinout, therefore they obviously can't (and don't need to)

be distinguished.

MAX6658 and MAX6659 variants. The extra features of the MAX6659 are only

supported by this driver if the chip is located at address 0x4d or 0x4e,

or if the chip type is explicitly selected as max6659.

The MAX6680 and MAX6681 only differ in their pinout, therefore they obviously

can't (and don't need to) be distinguished.

The specificity of this family of chipsets over the ADM1021/LM84

family is that it features critical limits with hysteresis, and an

  * Selectable address

  * Remote sensor type selection

MAX6695 and MAX6696:

  * Better local resolution

  * Selectable address (max6696)

  * Second critical temperature limit

  * Two remote sensors

W83L771W/G

  * The G variant is lead-free, otherwise similar to the W.

  * Filter and alert configuration register at 0xBF

  * Moving average (depending on conversion rate)

W83L771AWG/ASG

  * Successor of the W83L771W/G, same features.

  * The AWG and ASG variants only differ in package format.

  * Filter and alert configuration register at 0xBF

  * Diode ideality factor configuration (remote sensor) at 0xE3

  * Moving average (depending on conversion rate)

All temperature values are given in degrees Celsius. Resolution

is 1.0 degree for the local temperature, 0.125 degree for the remote

Supported chips:

  * Philips/NXP PCF8591

    Prefix: 'pcf8591'

    Addresses scanned: I2C 0x48 - 0x4f

    Addresses scanned: none

    Datasheet: Publicly available at the NXP website

               http://www.nxp.com/pip/PCF8591_6.html

Accessing PCF8591 via /sys interface

-------------------------------------

! Be careful !

The PCF8591 is plainly impossible to detect! Stupid chip.

So every chip with address in the interval [0x48..0x4f] is

detected as PCF8591. If you have other chips in this address

range, the workaround is to load this module after the one

for your others chips.

The PCF8591 is plainly impossible to detect! Thus the driver won't even

try. You have to explicitly instantiate the device at the relevant

address (in the interval [0x48..0x4f]) either through platform data, or

using the sysfs interface. See Documentation/i2c/instantiating-devices

for details.

On detection (i.e. insmod, modprobe et al.), directories are being

created for each detected PCF8591:

Directories are being created for each instantiated PCF8591:

/sys/bus/i2c/devices/<0>-<1>/

where <0> is the bus the chip was detected on (e. g. i2c-0)

where <0> is the bus the chip is connected to (e. g. i2c-0)

and <1> the chip address ([48..4f])

Inside these directories, there are such files:

		from the critical value.

		RW

temp[1-*]_emergency

		Temperature emergency max value, for chips supporting more than

		two upper temperature limits. Must be equal or greater than

		corresponding temp_crit values.

		Unit: millidegree Celsius

		RW

temp[1-*]_emergency_hyst

		Temperature hysteresis value for emergency limit.

		Unit: millidegree Celsius

		Must be reported as an absolute temperature, NOT a delta

		from the emergency value.

		RW

temp[1-*]_lcrit	Temperature critical min value, typically lower than

		corresponding temp_min values.

		Unit: millidegree Celsius

temp[1-*]_min_alarm

temp[1-*]_max_alarm

temp[1-*]_crit_alarm

temp[1-*]_emergency_alarm

		Limit alarm

		0: no alarm

		1: alarm