<!--
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  "availability" : [
    "DriverKit: 19.0 -"
  ],
  "documentType" : "symbol",
  "framework" : "USBDriverKit",
  "identifier" : "/documentation/USBDriverKit/tIOUSBTopology",
  "metadataVersion" : "0.1.0",
  "role" : "Enumeration",
  "symbol" : {
    "kind" : "Enumeration",
    "modules" : [
      "USBDriverKit"
    ],
    "preciseIdentifier" : "c:@E@tIOUSBTopology"
  },
  "title" : "tIOUSBTopology"
}
-->

# tIOUSBTopology

```
enum tIOUSBTopology : unsigned int;
```

## Topics

### Enumeration Cases

[`kIOUSBTopology1Hub`](/documentation/USBDriverKit/tIOUSBTopology/kIOUSBTopology1Hub)

[`kIOUSBTopology2Hub`](/documentation/USBDriverKit/tIOUSBTopology/kIOUSBTopology2Hub)

[`kIOUSBTopology3Hub`](/documentation/USBDriverKit/tIOUSBTopology/kIOUSBTopology3Hub)

[`kIOUSBTopology4Hub`](/documentation/USBDriverKit/tIOUSBTopology/kIOUSBTopology4Hub)

[`kIOUSBTopology5Hub`](/documentation/USBDriverKit/tIOUSBTopology/kIOUSBTopology5Hub)

[`kIOUSBTopologyHost`](/documentation/USBDriverKit/tIOUSBTopology/kIOUSBTopologyHost)

[`kIOUSBTopologyRootPort`](/documentation/USBDriverKit/tIOUSBTopology/kIOUSBTopologyRootPort)

[`kIOUSBTopologyTierLimit`](/documentation/USBDriverKit/tIOUSBTopology/kIOUSBTopologyTierLimit)

---

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