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Based on kernel version 3.13. Page generated on 2014-01-20 22:03 EST.

1	Kernel driver w83791d
2	=====================
3	
4	Supported chips:
5	  * Winbond W83791D
6	    Prefix: 'w83791d'
7	    Addresses scanned: I2C 0x2c - 0x2f
8	    Datasheet: http://www.winbond-usa.com/products/winbond_products/pdfs/PCIC/W83791D_W83791Gb.pdf
9	
10	Author: Charles Spirakis <bezaur@gmail.com>
11	
12	This driver was derived from the w83781d.c and w83792d.c source files.
13	
14	Credits:
15	  w83781d.c:
16	    Frodo Looijaard <frodol@dds.nl>,
17	    Philip Edelbrock <phil@netroedge.com>,
18	    and Mark Studebaker <mdsxyz123@yahoo.com>
19	  w83792d.c:
20	    Shane Huang (Winbond),
21	    Rudolf Marek <r.marek@assembler.cz>
22	
23	Additional contributors:
24	    Sven Anders <anders@anduras.de>
25	    Marc Hulsman <m.hulsman@tudelft.nl>
26	
27	Module Parameters
28	-----------------
29	
30	* init boolean
31	  (default 0)
32	  Use 'init=1' to have the driver do extra software initializations.
33	  The default behavior is to do the minimum initialization possible
34	  and depend on the BIOS to properly setup the chip. If you know you
35	  have a w83791d and you're having problems, try init=1 before trying
36	  reset=1.
37	
38	* reset boolean
39	  (default 0)
40	  Use 'reset=1' to reset the chip (via index 0x40, bit 7). The default
41	  behavior is no chip reset to preserve BIOS settings.
42	
43	* force_subclients=bus,caddr,saddr,saddr
44	  This is used to force the i2c addresses for subclients of
45	  a certain chip. Example usage is `force_subclients=0,0x2f,0x4a,0x4b'
46	  to force the subclients of chip 0x2f on bus 0 to i2c addresses
47	  0x4a and 0x4b.
48	
49	
50	Description
51	-----------
52	
53	This driver implements support for the Winbond W83791D chip. The W83791G
54	chip appears to be the same as the W83791D but is lead free.
55	
56	Detection of the chip can sometimes be foiled because it can be in an
57	internal state that allows no clean access (Bank with ID register is not
58	currently selected). If you know the address of the chip, use a 'force'
59	parameter; this will put it into a more well-behaved state first.
60	
61	The driver implements three temperature sensors, ten voltage sensors,
62	five fan rotation speed sensors and manual PWM control of each fan.
63	
64	Temperatures are measured in degrees Celsius and measurement resolution is 1
65	degC for temp1 and 0.5 degC for temp2 and temp3. An alarm is triggered when
66	the temperature gets higher than the Overtemperature Shutdown value; it stays
67	on until the temperature falls below the Hysteresis value.
68	
69	Voltage sensors (also known as IN sensors) report their values in millivolts.
70	An alarm is triggered if the voltage has crossed a programmable minimum
71	or maximum limit.
72	
73	Fan rotation speeds are reported in RPM (rotations per minute). An alarm is
74	triggered if the rotation speed has dropped below a programmable limit. Fan
75	readings can be divided by a programmable divider (1, 2, 4, 8, 16,
76	32, 64 or 128 for all fans) to give the readings more range or accuracy.
77	
78	Each fan controlled is controlled by PWM. The PWM duty cycle can be read and
79	set for each fan separately. Valid values range from 0 (stop) to 255 (full).
80	PWM 1-3 support Thermal Cruise mode, in which the PWMs are automatically
81	regulated to keep respectively temp 1-3 at a certain target temperature.
82	See below for the description of the sysfs-interface.
83	
84	The w83791d has a global bit used to enable beeping from the speaker when an
85	alarm is triggered as well as a bitmask to enable or disable the beep for
86	specific alarms. You need both the global beep enable bit and the
87	corresponding beep bit to be on for a triggered alarm to sound a beep.
88	
89	The sysfs interface to the global enable is via the sysfs beep_enable file.
90	This file is used for both legacy and new code.
91	
92	The sysfs interface to the beep bitmask has migrated from the original legacy
93	method of a single sysfs beep_mask file to a newer method using multiple
94	*_beep files as described in .../Documentation/hwmon/sysfs-interface.
95	
96	A similar change has occurred for the bitmap corresponding to the alarms. The
97	original legacy method used a single sysfs alarms file containing a bitmap
98	of triggered alarms. The newer method uses multiple sysfs *_alarm files
99	(again following the pattern described in sysfs-interface).
100	
101	Since both methods read and write the underlying hardware, they can be used
102	interchangeably and changes in one will automatically be reflected by
103	the other. If you use the legacy bitmask method, your user-space code is
104	responsible for handling the fact that the alarms and beep_mask bitmaps
105	are not the same (see the table below).
106	
107	NOTE: All new code should be written to use the newer sysfs-interface
108	specification as that avoids bitmap problems and is the preferred interface
109	going forward.
110	
111	The driver reads the hardware chip values at most once every three seconds.
112	User mode code requesting values more often will receive cached values.
113	
114	/sys files
115	----------
116	The sysfs-interface is documented in the 'sysfs-interface' file. Only
117	chip-specific options are documented here.
118	
119	pwm[1-3]_enable -	this file controls mode of fan/temperature control for
120				fan 1-3. Fan/PWM 4-5 only support manual mode.
121			            * 1 Manual mode
122			            * 2 Thermal Cruise mode
123			            * 3 Fan Speed Cruise mode (no further support)
124	
125	temp[1-3]_target -	defines the target temperature for Thermal Cruise mode.
126				Unit: millidegree Celsius
127				RW
128	
129	temp[1-3]_tolerance -	temperature tolerance for Thermal Cruise mode.
130				Specifies an interval around the target temperature
131				in which the fan speed is not changed.
132				Unit: millidegree Celsius
133				RW
134	
135	Alarms bitmap vs. beep_mask bitmask
136	------------------------------------
137	For legacy code using the alarms and beep_mask files:
138	
139	in0 (VCORE)  :  alarms: 0x000001 beep_mask: 0x000001
140	in1 (VINR0)  :  alarms: 0x000002 beep_mask: 0x002000 <== mismatch
141	in2 (+3.3VIN):  alarms: 0x000004 beep_mask: 0x000004
142	in3 (5VDD)   :  alarms: 0x000008 beep_mask: 0x000008
143	in4 (+12VIN) :  alarms: 0x000100 beep_mask: 0x000100
144	in5 (-12VIN) :  alarms: 0x000200 beep_mask: 0x000200
145	in6 (-5VIN)  :  alarms: 0x000400 beep_mask: 0x000400
146	in7 (VSB)    :  alarms: 0x080000 beep_mask: 0x010000 <== mismatch
147	in8 (VBAT)   :  alarms: 0x100000 beep_mask: 0x020000 <== mismatch
148	in9 (VINR1)  :  alarms: 0x004000 beep_mask: 0x004000
149	temp1        :  alarms: 0x000010 beep_mask: 0x000010
150	temp2        :  alarms: 0x000020 beep_mask: 0x000020
151	temp3        :  alarms: 0x002000 beep_mask: 0x000002 <== mismatch
152	fan1         :  alarms: 0x000040 beep_mask: 0x000040
153	fan2         :  alarms: 0x000080 beep_mask: 0x000080
154	fan3         :  alarms: 0x000800 beep_mask: 0x000800
155	fan4         :  alarms: 0x200000 beep_mask: 0x200000
156	fan5         :  alarms: 0x400000 beep_mask: 0x400000
157	tart1        :  alarms: 0x010000 beep_mask: 0x040000 <== mismatch
158	tart2        :  alarms: 0x020000 beep_mask: 0x080000 <== mismatch
159	tart3        :  alarms: 0x040000 beep_mask: 0x100000 <== mismatch
160	case_open    :  alarms: 0x001000 beep_mask: 0x001000
161	global_enable:  alarms: -------- beep_mask: 0x800000 (modified via beep_enable)
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