1What: /sys/class/extcon/.../ 2Date: February 2012 3Contact: 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 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 22What: /sys/class/extcon/.../name 23Date: February 2012 24Contact: MyungJoo Ham <myungjoo.ham@samsung.com> 25Description: 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 31What: /sys/class/extcon/.../state 32Date: February 2012 33Contact: MyungJoo Ham <myungjoo.ham@samsung.com> 34Description: 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 65What: /sys/class/extcon/.../cable.x/name 66Date: February 2012 67Contact: MyungJoo Ham <myungjoo.ham@samsung.com> 68Description: 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 72What: /sys/class/extcon/.../cable.x/state 73Date: February 2012 74Contact: MyungJoo Ham <myungjoo.ham@samsung.com> 75Description: 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 81What: /sys/class/extcon/.../mutually_exclusive/... 82Date: December 2011 83Contact: MyungJoo Ham <myungjoo.ham@samsung.com> 84Description: 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. 98