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+Kernel driver w83791d
+=====================
+
+Supported chips:
+
+ * Winbond W83791D
+
+ Prefix: 'w83791d'
+
+ Addresses scanned: I2C 0x2c - 0x2f
+
+ Datasheet: http://www.winbond-usa.com/products/winbond_products/pdfs/PCIC/W83791D_W83791Gb.pdf
+
+Author: Charles Spirakis <bezaur@gmail.com>
+
+This driver was derived from the w83781d.c and w83792d.c source files.
+
+Credits:
+
+ w83781d.c:
+
+ - Frodo Looijaard <frodol@dds.nl>,
+ - Philip Edelbrock <phil@netroedge.com>,
+ - Mark Studebaker <mdsxyz123@yahoo.com>
+
+ w83792d.c:
+
+ - Shane Huang (Winbond),
+ - Rudolf Marek <r.marek@assembler.cz>
+
+Additional contributors:
+
+ - Sven Anders <anders@anduras.de>
+ - Marc Hulsman <m.hulsman@tudelft.nl>
+
+Module Parameters
+-----------------
+
+* init boolean
+ (default 0)
+
+ Use 'init=1' to have the driver do extra software initializations.
+ The default behavior is to do the minimum initialization possible
+ and depend on the BIOS to properly setup the chip. If you know you
+ have a w83791d and you're having problems, try init=1 before trying
+ reset=1.
+
+* reset boolean
+ (default 0)
+
+ Use 'reset=1' to reset the chip (via index 0x40, bit 7). The default
+ behavior is no chip reset to preserve BIOS settings.
+
+* force_subclients=bus,caddr,saddr,saddr
+ This is used to force the i2c addresses for subclients of
+ a certain chip. Example usage is `force_subclients=0,0x2f,0x4a,0x4b`
+ to force the subclients of chip 0x2f on bus 0 to i2c addresses
+ 0x4a and 0x4b.
+
+
+Description
+-----------
+
+This driver implements support for the Winbond W83791D chip. The W83791G
+chip appears to be the same as the W83791D but is lead free.
+
+Detection of the chip can sometimes be foiled because it can be in an
+internal state that allows no clean access (Bank with ID register is not
+currently selected). If you know the address of the chip, use a 'force'
+parameter; this will put it into a more well-behaved state first.
+
+The driver implements three temperature sensors, ten voltage sensors,
+five fan rotation speed sensors and manual PWM control of each fan.
+
+Temperatures are measured in degrees Celsius and measurement resolution is 1
+degC for temp1 and 0.5 degC for temp2 and temp3. An alarm is triggered when
+the temperature gets higher than the Overtemperature Shutdown value; it stays
+on until the temperature falls below the Hysteresis value.
+
+Voltage sensors (also known as IN sensors) report their values in millivolts.
+An alarm is triggered if the voltage has crossed a programmable minimum
+or maximum limit.
+
+Fan rotation speeds are reported in RPM (rotations per minute). An alarm is
+triggered if the rotation speed has dropped below a programmable limit. Fan
+readings can be divided by a programmable divider (1, 2, 4, 8, 16,
+32, 64 or 128 for all fans) to give the readings more range or accuracy.
+
+Each fan controlled is controlled by PWM. The PWM duty cycle can be read and
+set for each fan separately. Valid values range from 0 (stop) to 255 (full).
+PWM 1-3 support Thermal Cruise mode, in which the PWMs are automatically
+regulated to keep respectively temp 1-3 at a certain target temperature.
+See below for the description of the sysfs-interface.
+
+The w83791d has a global bit used to enable beeping from the speaker when an
+alarm is triggered as well as a bitmask to enable or disable the beep for
+specific alarms. You need both the global beep enable bit and the
+corresponding beep bit to be on for a triggered alarm to sound a beep.
+
+The sysfs interface to the global enable is via the sysfs beep_enable file.
+This file is used for both legacy and new code.
+
+The sysfs interface to the beep bitmask has migrated from the original legacy
+method of a single sysfs beep_mask file to a newer method using multiple
+`*_beep` files as described in `Documentation/hwmon/sysfs-interface.rst`.
+
+A similar change has occurred for the bitmap corresponding to the alarms. The
+original legacy method used a single sysfs alarms file containing a bitmap
+of triggered alarms. The newer method uses multiple sysfs `*_alarm` files
+(again following the pattern described in sysfs-interface).
+
+Since both methods read and write the underlying hardware, they can be used
+interchangeably and changes in one will automatically be reflected by
+the other. If you use the legacy bitmask method, your user-space code is
+responsible for handling the fact that the alarms and beep_mask bitmaps
+are not the same (see the table below).
+
+NOTE: All new code should be written to use the newer sysfs-interface
+specification as that avoids bitmap problems and is the preferred interface
+going forward.
+
+The driver reads the hardware chip values at most once every three seconds.
+User mode code requesting values more often will receive cached values.
+
+/sys files
+----------
+The sysfs-interface is documented in the 'sysfs-interface' file. Only
+chip-specific options are documented here.
+
+======================= =======================================================
+pwm[1-3]_enable this file controls mode of fan/temperature control for
+ fan 1-3. Fan/PWM 4-5 only support manual mode.
+
+ * 1 Manual mode
+ * 2 Thermal Cruise mode
+ * 3 Fan Speed Cruise mode (no further support)
+
+temp[1-3]_target defines the target temperature for Thermal Cruise mode.
+ Unit: millidegree Celsius
+ RW
+
+temp[1-3]_tolerance temperature tolerance for Thermal Cruise mode.
+ Specifies an interval around the target temperature
+ in which the fan speed is not changed.
+ Unit: millidegree Celsius
+ RW
+======================= =======================================================
+
+Alarms bitmap vs. beep_mask bitmask
+-----------------------------------
+
+For legacy code using the alarms and beep_mask files:
+
+============= ======== ========= ==========================
+Signal Alarms beep_mask Obs
+============= ======== ========= ==========================
+in0 (VCORE) 0x000001 0x000001
+in1 (VINR0) 0x000002 0x002000 <== mismatch
+in2 (+3.3VIN) 0x000004 0x000004
+in3 (5VDD) 0x000008 0x000008
+in4 (+12VIN) 0x000100 0x000100
+in5 (-12VIN) 0x000200 0x000200
+in6 (-5VIN) 0x000400 0x000400
+in7 (VSB) 0x080000 0x010000 <== mismatch
+in8 (VBAT) 0x100000 0x020000 <== mismatch
+in9 (VINR1) 0x004000 0x004000
+temp1 0x000010 0x000010
+temp2 0x000020 0x000020
+temp3 0x002000 0x000002 <== mismatch
+fan1 0x000040 0x000040
+fan2 0x000080 0x000080
+fan3 0x000800 0x000800
+fan4 0x200000 0x200000
+fan5 0x400000 0x400000
+tart1 0x010000 0x040000 <== mismatch
+tart2 0x020000 0x080000 <== mismatch
+tart3 0x040000 0x100000 <== mismatch
+case_open 0x001000 0x001000
+global_enable - 0x800000 (modified via beep_enable)
+============= ======== ========= ==========================