host mode
plug in a device for test:
-
super speed device: usb3.0 usb-storage
-
high speed device: usb2.0 usb-storage
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full speed device: Pl2303 usb-serial device
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low speed device: usb mouse
1. xhci init
kernel xhci driver init ok
2. over-current
over-current signal
we should disable over-current signal or connect it to external power circuit correctly in haps validation env.
3. vbus
drive_vbus signal, enable vbus to power device.
4. detect a usb-storage attached
for usb2.0 full/high speed, D+ will be pulled up after device plug in, so host can see devcie attached.
for usb2.0 low speed, D- will be pulled up after device plug in.
xhci will generate a interrupt(Port Status Change Event)
xhci driver:
xhci_irq -> xhci_handle_event -> handl
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