Edit

IWDFDevice3::GetHardwareRegisterMappedAddress method (wudfddi.h)

  • Article

[Warning: UMDF 2 is the latest version of UMDF and supersedes UMDF 1. All new UMDF drivers should be written using UMDF 2. No new features are being added to UMDF 1 and there is limited support for UMDF 1 on newer versions of Windows 10. Universal Windows drivers must use UMDF 2. For more info, see Getting Started with UMDF.]

A driver calls GetHardwareRegisterMappedAddress to get the user-mode mapped address of the memory resource it earlier mapped using MapIoSpace.

Syntax

void * GetHardwareRegisterMappedAddress(
  [in] void *PseudoBaseAddress
);

Parameters

[in] PseudoBaseAddress

A pointer to the pseudo base address returned by a previous call to MapIoSpace.

Return value

User-mode base address of the resources mapped earlier using MapIoSpace.

Remarks

After the driver calls GetHardwareRegisterMappedAddress, it can access the user-mode address directly to read and write to the register.

Note  This is not the recommended approach for accessing registers because it prevents UMDF from doing any validation on the access.
 
For more information, see Reading and Writing to Device Registers in UMDF 1.x Drivers.

If you do use GetHardwareRegisterMappedAddress, you must set the UmdfRegisterAccessMode INF directive to RegisterAccessUsingUserModeMapping. For more information about UMDF INF directives, see Specifying WDF Directives in INF Files.

Requirements

Requirement Value
End of support Unavailable in UMDF 2.0 and later.
Target Platform Desktop
Minimum UMDF version 1.11
Header wudfddi.h
DLL WUDFx.dll

See also

IWDFDevice3