18c2ecf20Sopenharmony_ciWhat:		Raise a uevent when a USB charger is inserted or removed
28c2ecf20Sopenharmony_ciDate:		2020-01-14
38c2ecf20Sopenharmony_ciKernelVersion:	5.6
48c2ecf20Sopenharmony_ciContact:	linux-usb@vger.kernel.org
58c2ecf20Sopenharmony_ciDescription:	There are two USB charger states:
68c2ecf20Sopenharmony_ci
78c2ecf20Sopenharmony_ci		- USB_CHARGER_ABSENT
88c2ecf20Sopenharmony_ci		- USB_CHARGER_PRESENT
98c2ecf20Sopenharmony_ci
108c2ecf20Sopenharmony_ci		There are five USB charger types:
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128c2ecf20Sopenharmony_ci		========================  ==========================
138c2ecf20Sopenharmony_ci		USB_CHARGER_UNKNOWN_TYPE  Charger type is unknown
148c2ecf20Sopenharmony_ci		USB_CHARGER_SDP_TYPE      Standard Downstream Port
158c2ecf20Sopenharmony_ci		USB_CHARGER_CDP_TYPE      Charging Downstream Port
168c2ecf20Sopenharmony_ci		USB_CHARGER_DCP_TYPE      Dedicated Charging Port
178c2ecf20Sopenharmony_ci		USB_CHARGER_ACA_TYPE      Accessory Charging Adapter
188c2ecf20Sopenharmony_ci		========================  ==========================
198c2ecf20Sopenharmony_ci
208c2ecf20Sopenharmony_ci		https://www.usb.org/document-library/battery-charging-v12-spec-and-adopters-agreement
218c2ecf20Sopenharmony_ci
228c2ecf20Sopenharmony_ci		Here are two examples taken using ``udevadm monitor -p`` when
238c2ecf20Sopenharmony_ci		USB charger is online::
248c2ecf20Sopenharmony_ci
258c2ecf20Sopenharmony_ci		    UDEV  change   /devices/soc0/usbphynop1 (platform)
268c2ecf20Sopenharmony_ci		    ACTION=change
278c2ecf20Sopenharmony_ci		    DEVPATH=/devices/soc0/usbphynop1
288c2ecf20Sopenharmony_ci		    DRIVER=usb_phy_generic
298c2ecf20Sopenharmony_ci		    MODALIAS=of:Nusbphynop1T(null)Cusb-nop-xceiv
308c2ecf20Sopenharmony_ci		    OF_COMPATIBLE_0=usb-nop-xceiv
318c2ecf20Sopenharmony_ci		    OF_COMPATIBLE_N=1
328c2ecf20Sopenharmony_ci		    OF_FULLNAME=/usbphynop1
338c2ecf20Sopenharmony_ci		    OF_NAME=usbphynop1
348c2ecf20Sopenharmony_ci		    SEQNUM=2493
358c2ecf20Sopenharmony_ci		    SUBSYSTEM=platform
368c2ecf20Sopenharmony_ci		    USB_CHARGER_STATE=USB_CHARGER_PRESENT
378c2ecf20Sopenharmony_ci		    USB_CHARGER_TYPE=USB_CHARGER_SDP_TYPE
388c2ecf20Sopenharmony_ci		    USEC_INITIALIZED=227422826
398c2ecf20Sopenharmony_ci
408c2ecf20Sopenharmony_ci		USB charger is offline::
418c2ecf20Sopenharmony_ci
428c2ecf20Sopenharmony_ci		    KERNEL change   /devices/soc0/usbphynop1 (platform)
438c2ecf20Sopenharmony_ci		    ACTION=change
448c2ecf20Sopenharmony_ci		    DEVPATH=/devices/soc0/usbphynop1
458c2ecf20Sopenharmony_ci		    DRIVER=usb_phy_generic
468c2ecf20Sopenharmony_ci		    MODALIAS=of:Nusbphynop1T(null)Cusb-nop-xceiv
478c2ecf20Sopenharmony_ci		    OF_COMPATIBLE_0=usb-nop-xceiv
488c2ecf20Sopenharmony_ci		    OF_COMPATIBLE_N=1
498c2ecf20Sopenharmony_ci		    OF_FULLNAME=/usbphynop1
508c2ecf20Sopenharmony_ci		    OF_NAME=usbphynop1
518c2ecf20Sopenharmony_ci		    SEQNUM=2494
528c2ecf20Sopenharmony_ci		    SUBSYSTEM=platform
538c2ecf20Sopenharmony_ci		    USB_CHARGER_STATE=USB_CHARGER_ABSENT
548c2ecf20Sopenharmony_ci		    USB_CHARGER_TYPE=USB_CHARGER_UNKNOWN_TYPE
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