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# IOUSBGetConfigurationMaxPowerMilliAmps(_:_:)

Obtains the maximum bus current that a configuration descriptor requires.

```
func IOUSBGetConfigurationMaxPowerMilliAmps(_ usbDeviceSpeed: UInt32, _ descriptor: UnsafePointer<IOUSBConfigurationDescriptor>!) -> UInt32
```

## Parameters

`usbDeviceSpeed`

The operational speed of the device.

`descriptor`

The configuration descriptor to parse.

## Return Value

The number of milliamps necessary.

## Discussion

This method parses a configuration descriptor and returns the number of milliamps necessary to power the device.

---

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