低电时限制USB反向充电

如何识别当前的USB连接是向别的设备充电？

       最好的方式是获取USB的供电电流，如果当前低电量，而且供电电流太大，则对USB总线断电。但是在USB服务上没法似乎无法获得供电电流。按功能是否可行？如果USB没有配置音频、视频、录音、录像、拍照, otg存储等功能，也就是没有常用的defined codes, 则掐断电源。

场景	mode	power	data	class	sub-c	组合	备注
pc  充电	ufp	sink	device	/	/	2	[source:host, sink:device]
pc  mtp	ufp	sink	device	/	/	2
pc ptp	ufp	sink	device	/	/	2
pc cdrom	ufp	sink	device	/	/	2
pc rndis	/	/	/	/	/	/	不支持rndis
充电头	dfp	sink	host	/	/	3	[source:host, sink:host, sink:device]
充电头	ufp	sink	device	/	/	2	[source:host, sink:device]
headset	dfp	source	host	6	1	2
otg udisk		source	host			2
printer		source	host			2
y31s 充电	dfp	source	host	8	6	2
790 充电	ufp	sink	device			4	[source:host, source:device, sink:host, sink:device]
790 mtp	ufp	sink	device			4
790 ptp	ufp	sink	device			4
790cdrom	ufp	sink	device			4
790 充电		sink	host	255	255	4	受电方可以弹起连接选择框，虽可以
790 mtp		sink	host	6	1	4	弹起，但是如果切换连接方式，则虽配置
790 ptp		sink	host	6	1	4	成功，但连接会失败的，因为一个主设备
790cdrom		sink	host	8	6	4	企图gadget连接从设备，是不允许的。
790 充电	ufp	source	device			4	供电方不能弹起连接选择框，但是可以
790 mtp		source	device			4	通过svc usb setFunctions mtp等命令切换
790 ptp		source	device			4	连接方式
790cdrom		source	device			4
790 充电	dfp	source	host	255	255	4
790 mtp		source	host	6	1	4
790 ptp		source	host	6	1	4
790cdrom		source	host	8	6	4

Defined Class Codes 类型

Base Class	Descriptor Usage	Description
00h	Device	Use class information in the Interface Descriptors
01h	Interface	Audio
02h	Both	Communications and CDC Control
03h	Interface	HID (Human Interface Device)
05h	Interface	Physical
06h	Interface	Image
07h	Interface	Printer
08h	Interface	Mass Storage
09h	Device	Hub
0Ah	Interface	CDC-Data
0Bh	Interface	Smart Card
0Dh	Interface	Content Security
0Eh	Interface	Video
0Fh	Interface	Personal Healthcare
10h	Interface	Audio/Video Devices
11h	Device	Billboard Device Class
12h	Interface	USB Type-C Bridge Class
3Ch	Interface	I3C Device Class
DCh	Both	Diagnostic Device
E0h	Interface	Wireless Controller
EFh	Both	Miscellaneous
FEh	Interface	Application Specific
FFh	Both	Vendor Specific

USB 耳机

07-14 15:34:06.836  1091  2461 I [email protected]: auto suspend usb interfaces /sys/devices/platform/soc/a600000.ssusb/a600000.dwc3/xhci-hcd.2.auto/usb2/2-1
07-14 15:33:51.712 21715 21715 I [21715:kworker/0:3]input: bestechnic HUAWEI USB-C HEADSET as /devices/platform/soc/a600000.ssusb/a600000.dwc3/xhci-hcd.2.auto/usb2/2-1/2-1:1.3/0003:12D1:3A07.0001/input/input6
07-14 15:33:51.784 21715 21715 I [21715:kworker/0:3]hid-generic 0003: 12D1:3A07.0001: input,hidraw0: USB HID v1.11 Device [bestechnic HUAWEI USB-C HEADSET] on usb-xhci-hcd.2.auto-1/input3
07-14 15:34:06.941 12615 12821 D EventHub: No input device configuration file found for device 'bestechnic HUAWEI USB-C HEADSET'.
07-14 15:34:06.947  1091  2461 I [email protected]: auto suspend usb interfaces /sys/devices/platform/soc/a600000.ssusb/a600000.dwc3/xhci-hcd.2.auto/usb2/2-1
07-14 15:34:06.950 12615 12939 D UsbHostManager: USB device attached: vidpid 12d1:3a07 mfg/product/ver/serial bestechnic/HUAWEI USB-C HEADSET/0.24/0296A100000000000000000000000 hasAudio/HID/Storage: true/true/false
07-14 15:34:06.955 12615 12939 D UsbDeviceDescriptor:   1 configs
07-14 15:34:06.958 12615 12939 D UsbHostManager: Added device UsbDevice[mName=/dev/bus/usb/002/002,mVendorId=4817,mProductId=14855,mClass=0,mSubclass=0,mProtocol=0,mManufacturerName=bestechnic,mProductName=HUAWEI USB-C HEADSET,mVersion=0.24,mSerialNumberReader=com.android.server.usb.UsbSerialReader@fb536d0, mHasAudioPlayback=true, mHasAudioCapture=true, mHasMidi=false, mHasVideoCapture=false, mHasVideoPlayback=false, mConfigurations=[
07-14 15:34:06.958 12615 12939 D UsbHostManager: UsbConfiguration[mId=1,mName=null,mAttributes=160,mMaxPower=50,mInterfaces=[
07-14 15:34:06.958 12615 12939 D UsbHostManager: UsbInterface[mId=0,mAlternateSetting=0,mName=null,mClass=1,mSubclass=1,mProtocol=0,mEndpoints=[]
07-14 15:34:06.958 12615 12939 D UsbHostManager: UsbInterface[mId=1,mAlternateSetting=0,mName=null,mClass=1,mSubclass=2,mProtocol=0,mEndpoints=[]
07-14 15:34:06.958 12615 12939 D UsbHostManager: UsbInterface[mId=1,mAlternateSetting=1,mName=null,mClass=1,mSubclass=2,mProtocol=0,mEndpoints=[
07-14 15:34:06.958 12615 12939 D UsbHostManager: UsbEndpoint[mAddress=131,mAttributes=13,mMaxPacketSize=192,mInterval=1]]
07-14 15:34:06.958 12615 12939 D UsbHostManager: UsbInterface[mId=2,mAlternateSetting=0,mName=null,mClass=1,mSubclass=2,mProtocol=0,mEndpoints=[]
07-14 15:34:06.958 12615 12939 D UsbHostManager: UsbInterface[mId=2,mAlternateSetting=1,mName=null,mClass=1,mSubclass=2,mProtocol=0,mEndpoints=[
07-14 15:34:06.958 12615 12939 D UsbHostManager: UsbEndpoint[mAddress=3,mAttributes=13,mMaxPacketSize=384,mInterval=1]]
07-14 15:34:06.958 12615 12939 D UsbHostManager: UsbInterface[mId=2,mAlternateSetting=2,mName=null,mClass=1,mSubclass=2,mProtocol=0,mEndpoints=[
07-14 15:34:06.958 12615 12939 D UsbHostManager: UsbEndpoint[mAddress=3,mAttributes=13,mMaxPacketSize=576,mInterval=1]]
07-14 15:34:06.958 12615 12939 D UsbHostManager: UsbInterface[mId=3,mAlternateSetting=0,mName=null,mClass=3,mSubclass=0,mProtocol=0,mEndpoints=[
07-14 15:34:06.958 12615 12939 D UsbHostManager:

UsbEndpoint[mAddress=132,mAttributes=3,mMaxPacketSize=3,mInterval=1]]]]

对端是 DRP端口的手机，仅充电config

07-14 17:59:40.935 11994 11994 I [11994:kworker/u16:2]hub 3-0: 1.0: 1 port detected
07-14 17:59:41.488  1091  2461 I [email protected]: uevent received change@/devices/platform/soc/soc:qcom,pmic_glink/soc:qcom,pmic_glink:qcom,ucsi/typec/port0
07-14 17:59:41.496  1091  2461 I [email protected]: port0
07-14 17:59:41.499  1091  2461 I [email protected]: connected:1 canChangeMode:1 canChagedata:1 canChangePower:1
07-14 17:59:41.501 12615 12911 I UsbPortManager: ClientCallback V1_2: port0
07-14 17:59:41.502 12615 12648 I UsbPortManager: USB port changed: port=UsbPort{id=port0, supportedModes=dual, audio_accsupportedContaminantProtectionModes=5supportsEnableContaminantPresenceProtection=falsesupportsEnableContaminantPresenceDetection=false, status=UsbPortStatus{connected=true, currentMode=dfp, currentPowerRole=source, currentDataRole=host, supportedRoleCombinations=[source:host, source:device, sink:host, sink:device], contaminantDetectionStatus=2, contaminantProtectionStatus=1}, canChangeMode=true, canChangePowerRole=true, canChangeDataRole=true, connectedAtMillis=14369516, lastConnectDurationMillis=0
07-14 17:59:41.504 12615 12615 I UsbDeviceManager: updateHostState UsbPort{id=port0, supportedModes=dual, audio_accsupportedContaminantProtectionModes=5supportsEnableContaminantPresenceProtection=falsesupportsEnableContaminantPresenceDetection=false status=UsbPortStatus{connected=true, currentMode=dfp, currentPowerRole=source, currentDataRole=host, supportedRoleCombinations=[source:host, source:device, sink:host, sink:device], contaminantDetectionStatus=2, contaminantProtectionStatus=1}
07-14 17:59:41.341 31352 31352 I [31352:kworker/0:2]usb 2-1: new high-speed USB device number 2 using xhci-hcd
07-14 17:59:41.500 31352 31352 I [31352:kworker/0:2]usb 2-1: New USB device found, VID=109b, PID=90be
07-14 17:59:42.011 12615 12939 D UsbHostManager: USB device attached: vidpid 109b:90be mfg/product/ver/serial Android/Android/5.04/ABCDEFGH hasAudio/HID/Storage: false/false/false
07-14 17:59:42.020 12615 12939 D UsbDeviceDescriptor:   1 configs
07-14 17:59:42.038 12615 12939 D UsbHostManager: Added device UsbDevice[mName=/dev/bus/usb/002/002,mVendorId=4251,mProductId=37054,mClass=0,mSubclass=0,mProtocol=0,mManufacturerName=Android,mProductName=Android,mVersion=5.04,mSerialNumberReader=com.android.server.usb.UsbSerialReader@c9820d6, mHasAudioPlayback=false, mHasAudioCapture=false, mHasMidi=false, mHasVideoCapture=false, mHasVideoPlayback=false, mConfigurations=[
07-14 17:59:42.038 12615 12939 D UsbHostManager: UsbConfiguration[mId=1,mName=diag_adb,mAttributes=192,mMaxPower=0,mInterfaces=[
07-14 17:59:42.038 12615 12939 D UsbHostManager: UsbInterface[mId=0,mAlternateSetting=0,mName=null,mClass=255,mSubclass=255,mProtocol=48,mEndpoints=[
07-14 17:59:42.038 12615 12939 D UsbHostManager: UsbEndpoint[mAddress=1,mAttributes=2,mMaxPacketSize=512,mInterval=0]
07-14 17:59:42.038 12615 12939 D UsbHostManager: UsbEndpoint[mAddress=129,mAttributes=2,mMaxPacketSize=512,mInterval=0]]
07-14 17:59:42.038 12615 12939 D UsbHostManager: UsbInterface[mId=1,mAlternateSetting=0,mName=ADB Interface,mClass=255,mSubclass=66,mProtocol=1,mEndpoints=[
07-14 17:59:42.038 12615 12939 D UsbHostManager: UsbEndpoint[mAddress=2,mAttributes=2,mMaxPacketSize=512,mInterval=0]
07-14 17:59:42.038 12615 12939 D UsbHostManager: UsbEndpoint[mAddress=130,mAttributes=2,mMaxPacketSize=512,mInterval=0]]]]
07-14 17:59:42.047 12615 12615 D AS.AudioService: onReceive()  action= android.hardware.usb.action.USB_DEVICE_ATTACHED

对端是手机且设置为mtp

07-14 18:10:49.967 12615 12939 D UsbHostManager: USB device attached: vidpid 109b:9135 mfg/product/ver/serial Android/Android/5.04/ABCDEFGH hasAudio/HID/Storage: false/false/false
07-14 18:10:49.972 12615 12939 D UsbDeviceDescriptor:   1 configs
07-14 18:10:49.991 12615 12939 D UsbHostManager: Added device UsbDevice[mName=/dev/bus/usb/002/003,mVendorId=4251,mProductId=37173,mClass=0,mSubclass=0,mProtocol=0,mManufacturerName=Android,mProductName=Android,mVersion=5.04,mSerialNumberReader=com.android.server.usb.UsbSerialReader@6872391, mHasAudioPlayback=false, mHasAudioCapture=false, mHasMidi=false, mHasVideoCapture=false, mHasVideoPlayback=false, mConfigurations=[
07-14 18:10:49.991 12615 12939 D UsbHostManager: UsbConfiguration[mId=1,mName=mtp_adb,mAttributes=192,mMaxPower=0,mInterfaces=[
07-14 18:10:49.991 12615 12939 D UsbHostManager: UsbInterface[mId=0,mAlternateSetting=0,mName=MTP,mClass=6,mSubclass=1,mProtocol=1,mEndpoints=[
07-14 18:10:49.991 12615 12939 D UsbHostManager: UsbEndpoint[mAddress=129,mAttributes=2,mMaxPacketSize=512,mInterval=0]
07-14 18:10:49.991 12615 12939 D UsbHostManager: UsbEndpoint[mAddress=1,mAttributes=2,mMaxPacketSize=512,mInterval=0]
07-14 18:10:49.991 12615 12939 D UsbHostManager: UsbEndpoint[mAddress=130,mAttributes=3,mMaxPacketSize=28,mInterval=6]]
07-14 18:10:49.991 12615 12939 D UsbHostManager: UsbInterface[mId=1,mAlternateSetting=0,mName=ADB Interface,mClass=255,mSubclass=66,mProtocol=1,mEndpoints=[
07-14 18:10:49.991 12615 12939 D UsbHostManager: UsbEndpoint[mAddress=2,mAttributes=2,mMaxPacketSize=512,mInterval=0]
07-14 18:10:49.991 12615 12939 D UsbHostManager: UsbEndpoint[mAddress=131,mAttributes=2,mMaxPacketSize=512,mInterval=0]]]]