26 lines
1.0 KiB
Plaintext
26 lines
1.0 KiB
Plaintext
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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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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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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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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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