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1What: /sys/class/extcon/.../2Date: February 20123Contact: MyungJoo Ham <myungjoo.ham@samsung.com>4Description: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 given8 with extcon_dev_register.9 10 One extcon device denotes a single external connector11 port. An external connector may have multiple cables12 attached simultaneously. Many of docks, cradles, and13 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's20 mutually_exclusive array.21 22What: /sys/class/extcon/.../name23Date: February 201224Contact: MyungJoo Ham <myungjoo.ham@samsung.com>25Description:26 The /sys/class/extcon/.../name shows the name of the extcon27 object. If the extcon object has an optional callback28 "show_name" defined, the callback will provide the name with29 this sysfs node.30 31What: /sys/class/extcon/.../state32Date: February 201233Contact: MyungJoo Ham <myungjoo.ham@samsung.com>34Description:35 The /sys/class/extcon/.../state shows and stores the cable36 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 optional39 callback.40 41 If the default callback for showing function is used, the42 format is like this::43 44 # cat state45 USB_OTG=146 HDMI=047 TA=148 EAR_JACK=049 #50 51 In this example, the extcon device has USB_OTG and TA52 cables attached and HDMI and EAR_JACK cables detached.53 54 In order to update the state of an extcon device, enter a hex55 state number starting with 0x::56 57 # echo 0xHEX > state58 59 This updates the whole state of the extcon device.60 Inputs of all the methods are required to meet the61 mutually_exclusive conditions if they exist.62 63 It is recommended to use this "global" state interface if64 you need to set the value atomically. The later state65 interface associated with each cable cannot update66 multiple cable states of an extcon device simultaneously.67 68What: /sys/class/extcon/.../cable.X/name69Date: February 201270Contact: MyungJoo Ham <myungjoo.ham@samsung.com>71Description:72 The /sys/class/extcon/.../cable.X/name shows the name of cable73 "X" (integer between 0 and 31) of an extcon device.74 75What: /sys/class/extcon/.../cable.X/state76Date: February 201277Contact: MyungJoo Ham <myungjoo.ham@samsung.com>78Description:79 The /sys/class/extcon/.../cable.X/state shows and stores the80 state of cable "X" (integer between 0 and 31) of an extcon81 device. The state value is either 0 (detached) or 182 (attached).83 84What: /sys/class/extcon/.../mutually_exclusive/...85Date: December 201186Contact: MyungJoo Ham <myungjoo.ham@samsung.com>87Description:88 Shows the relations of mutually exclusiveness. For example,89 if the mutually_exclusive array of extcon device is90 {0x3, 0x5, 0xC, 0x0}, then the output is::91 92 # ls mutually_exclusive/93 0x394 0x595 0xc96 #97 98 Note that mutually_exclusive is a sub-directory of the extcon99 device and the file names under the mutually_exclusive100 directory show the mutually-exclusive sets, not the contents101 of the files.102