---
title: "IOUSBGetConfigurationMaxPowerMilliAmps(_:_:)"
framework: iousbhost
role: symbol
role_heading: Function
path: "iousbhost/iousbgetconfigurationmaxpowermilliamps(_:_:)"
---

# IOUSBGetConfigurationMaxPowerMilliAmps(_:_:)

Obtains the maximum bus current that a configuration descriptor requires.

## Declaration

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

## Parameters

- `usbDeviceSpeed`: The operational speed of the device.
- `descriptor`: The configuration descriptor to parse.

## Return Value

Return Value The number of milliamps necessary.

## Discussion

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

## See Also

### Configuration Descriptor Parsing

- [IOUSBGetNextDescriptor(_:_:)](iousbhost/iousbgetnextdescriptor(_:_:).md)
- [IOUSBGetNextDescriptorWithType(_:_:_:)](iousbhost/iousbgetnextdescriptorwithtype(_:_:_:).md)
- [IOUSBGetNextAssociatedDescriptor(_:_:_:)](iousbhost/iousbgetnextassociateddescriptor(_:_:_:).md)
- [IOUSBGetNextAssociatedDescriptorWithType(_:_:_:_:)](iousbhost/iousbgetnextassociateddescriptorwithtype(_:_:_:_:).md)
- [IOUSBGetNextInterfaceAssociationDescriptor(_:_:)](iousbhost/iousbgetnextinterfaceassociationdescriptor(_:_:).md)
- [IOUSBGetNextInterfaceDescriptor(_:_:)](iousbhost/iousbgetnextinterfacedescriptor(_:_:).md)