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Based on kernel version 3.16. Page generated on 2014-08-06 21:35 EST.

1	What:		/sys/class/extcon/.../
2	Date:		February 2012
3	Contact:	MyungJoo Ham <myungjoo.ham@samsung.com>
4	Description:
5			Provide a place in sysfs for the extcon objects.
6			This allows accessing extcon specific variables.
7			The name of extcon object denoted as ... is the name given
8			with extcon_dev_register.
9	
10			One extcon device denotes a single external connector
11			port. An external connector may have multiple cables
12			attached simultaneously. Many of docks, cradles, and
13			accessory cables have such capability. For example,
14			the 30-pin port of Nuri board (/arch/arm/mach-exynos)
15			may have both HDMI and Charger attached, or analog audio,
16			video, and USB cables attached simultaneously.
17	
18			If there are cables mutually exclusive with each other,
19			such binary relations may be expressed with extcon_dev's
20			mutually_exclusive array.
21	
22	What:		/sys/class/extcon/.../name
23	Date:		February 2012
24	Contact:	MyungJoo Ham <myungjoo.ham@samsung.com>
25	Description:
26			The /sys/class/extcon/.../name shows the name of the extcon
27			object. If the extcon object has an optional callback
28			"show_name" defined, the callback will provide the name with
29			this sysfs node.
30	
31	What:		/sys/class/extcon/.../state
32	Date:		February 2012
33	Contact:	MyungJoo Ham <myungjoo.ham@samsung.com>
34	Description:
35			The /sys/class/extcon/.../state shows and stores the cable
36			attach/detach information of the corresponding extcon object.
37			If the extcon object has an optional callback "show_state"
38			defined, the showing function is overridden with the optional
39			callback.
40	
41			If the default callback for showing function is used, the
42			format is like this:
43			# cat state
44			USB_OTG=1
45			HDMI=0
46			TA=1
47			EAR_JACK=0
48			#
49			In this example, the extcon device has USB_OTG and TA
50			cables attached and HDMI and EAR_JACK cables detached.
51	
52			In order to update the state of an extcon device, enter a hex
53			state number starting with 0x:
54			# echo 0xHEX > state
55	
56			This updates the whole state of the extcon device.
57			Inputs of all the methods are required to meet the
58			mutually_exclusive conditions if they exist.
59	
60			It is recommended to use this "global" state interface if
61			you need to set the value atomically. The later state
62			interface associated with each cable cannot update
63			multiple cable states of an extcon device simultaneously.
64	
65	What:		/sys/class/extcon/.../cable.x/name
66	Date:		February 2012
67	Contact:	MyungJoo Ham <myungjoo.ham@samsung.com>
68	Description:
69			The /sys/class/extcon/.../cable.x/name shows the name of cable
70			"x" (integer between 0 and 31) of an extcon device.
71	
72	What:		/sys/class/extcon/.../cable.x/state
73	Date:		February 2012
74	Contact:	MyungJoo Ham <myungjoo.ham@samsung.com>
75	Description:
76			The /sys/class/extcon/.../cable.x/state shows and stores the
77			state of cable "x" (integer between 0 and 31) of an extcon
78			device. The state value is either 0 (detached) or 1
79			(attached).
80	
81	What:		/sys/class/extcon/.../mutually_exclusive/...
82	Date:		December 2011
83	Contact:	MyungJoo Ham <myungjoo.ham@samsung.com>
84	Description:
85			Shows the relations of mutually exclusiveness. For example,
86			if the mutually_exclusive array of extcon device is
87			{0x3, 0x5, 0xC, 0x0}, then the output is:
88			# ls mutually_exclusive/
89			0x3
90			0x5
91			0xc
92			#
93	
94			Note that mutually_exclusive is a sub-directory of the extcon
95			device and the file names under the mutually_exclusive
96			directory show the mutually-exclusive sets, not the contents
97			of the files.
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