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			26 lines
		
	
	
		
			1.0 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
| What:		/sys/bus/pci/drivers/xhci_hcd/.../dbc
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| Date:		June 2017
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| Contact:	Lu Baolu <baolu.lu@linux.intel.com>
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| Description:
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| 		xHCI compatible USB host controllers (i.e. super-speed
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| 		USB3 controllers) are often implemented with the Debug
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| 		Capability (DbC). It can present a debug device which
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| 		is fully compliant with the USB framework and provides
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| 		the equivalent of a very high performance full-duplex
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| 		serial link for debug purpose.
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| 
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| 		The DbC debug device shares a root port with xHCI host.
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| 		When the DbC is enabled, the root port will be assigned
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| 		to the Debug Capability. Otherwise, it will be assigned
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| 		to xHCI.
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| 
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| 		Writing "enable" to this attribute will enable the DbC
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| 		functionality and the shared root port will be assigned
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| 		to the DbC device. Writing "disable" to this attribute
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| 		will disable the DbC functionality and the shared root
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| 		port will roll back to the xHCI.
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| 
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| 		Reading this attribute gives the state of the DbC. It
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| 		can be one of the following states: disabled, enabled,
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| 		initialized, connected, configured and stalled.
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