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