188008266SPeter ChenWhat:		Raise a uevent when a USB charger is inserted or removed
288008266SPeter ChenDate:		2020-01-14
388008266SPeter ChenKernelVersion:	5.6
488008266SPeter ChenContact:	linux-usb@vger.kernel.org
588008266SPeter ChenDescription:	There are two USB charger states:
688008266SPeter Chen		USB_CHARGER_ABSENT
788008266SPeter Chen		USB_CHARGER_PRESENT
888008266SPeter Chen		There are five USB charger types:
988008266SPeter Chen		USB_CHARGER_UNKNOWN_TYPE: Charger type is unknown
1088008266SPeter Chen		USB_CHARGER_SDP_TYPE: Standard Downstream Port
1188008266SPeter Chen		USB_CHARGER_CDP_TYPE: Charging Downstream Port
1288008266SPeter Chen		USB_CHARGER_DCP_TYPE: Dedicated Charging Port
1388008266SPeter Chen		USB_CHARGER_ACA_TYPE: Accessory Charging Adapter
1488008266SPeter Chen		https://www.usb.org/document-library/battery-charging-v12-spec-and-adopters-agreement
1588008266SPeter Chen
1688008266SPeter Chen		Here are two examples taken using udevadm monitor -p when
1788008266SPeter Chen		USB charger is online:
1888008266SPeter Chen		UDEV  change   /devices/soc0/usbphynop1 (platform)
1988008266SPeter Chen		ACTION=change
2088008266SPeter Chen		DEVPATH=/devices/soc0/usbphynop1
2188008266SPeter Chen		DRIVER=usb_phy_generic
2288008266SPeter Chen		MODALIAS=of:Nusbphynop1T(null)Cusb-nop-xceiv
2388008266SPeter Chen		OF_COMPATIBLE_0=usb-nop-xceiv
2488008266SPeter Chen		OF_COMPATIBLE_N=1
2588008266SPeter Chen		OF_FULLNAME=/usbphynop1
2688008266SPeter Chen		OF_NAME=usbphynop1
2788008266SPeter Chen		SEQNUM=2493
2888008266SPeter Chen		SUBSYSTEM=platform
2988008266SPeter Chen		USB_CHARGER_STATE=USB_CHARGER_PRESENT
3088008266SPeter Chen		USB_CHARGER_TYPE=USB_CHARGER_SDP_TYPE
3188008266SPeter Chen		USEC_INITIALIZED=227422826
3288008266SPeter Chen
3388008266SPeter Chen		USB charger is offline:
3488008266SPeter Chen		KERNEL change   /devices/soc0/usbphynop1 (platform)
3588008266SPeter Chen		ACTION=change
3688008266SPeter Chen		DEVPATH=/devices/soc0/usbphynop1
3788008266SPeter Chen		DRIVER=usb_phy_generic
3888008266SPeter Chen		MODALIAS=of:Nusbphynop1T(null)Cusb-nop-xceiv
3988008266SPeter Chen		OF_COMPATIBLE_0=usb-nop-xceiv
4088008266SPeter Chen		OF_COMPATIBLE_N=1
4188008266SPeter Chen		OF_FULLNAME=/usbphynop1
4288008266SPeter Chen		OF_NAME=usbphynop1
4388008266SPeter Chen		SEQNUM=2494
4488008266SPeter Chen		SUBSYSTEM=platform
4588008266SPeter Chen		USB_CHARGER_STATE=USB_CHARGER_ABSENT
4688008266SPeter Chen		USB_CHARGER_TYPE=USB_CHARGER_UNKNOWN_TYPE
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