Re: [edk2-devel] [PATCH V2 2/4] MdeModulePkg/Include: Add DeviceSecurity.h

["Yao, Jiewen" <jiewen.yao@intel.com>]

HI
Good comment. Let me answer it in 2 parts.

1) The consumer may locate the deice path to know the device type. In this part, you can treat this as redundant information.

2) But we still need a new GUID, because I will install the device access protocol on this new GUID for the temporary access for the authentication driver only.

I don't want to install the device access protocol to the original UEFI spec defined GUID to notify everyone that the device is ready to use, because I have seen some device drivers have callback function (such as ATA passthru, or NVME passthru) to start access the device once the device access protocol is installed.


Thank you
Yao Jiewen

> -----Original Message-----
> From: Ni, Ray <ray.ni@intel.com>
> Sent: Wednesday, November 6, 2019 3:56 PM
> To: devel@edk2.groups.io; Yao, Jiewen <jiewen.yao@intel.com>
> Cc: Wang, Jian J <jian.j.wang@intel.com>; Wu, Hao A <hao.a.wu@intel.com>;
> Lou, Yun <yun.lou@intel.com>
> Subject: RE: [edk2-devel] [PATCH V2 2/4] MdeModulePkg/Include: Add
> DeviceSecurity.h
> 
> > +  ///
> > +  /// Type of the device.
> > +  /// This field is also served as a device Access protocol GUID.
> > +  /// The device access protocol is installed on the DeviceHandle.
> > +  /// The device access protocol is device specific.
> > +  ///   EDKII_DEVICE_IDENTIFIER_TYPE_PCI_GUID means the device access
> protocol is PciIo.
> > +  ///   EDKII_DEVICE_IDENTIFIER_TYPE_USB_GUID means the device access
> protocol is UsbIo.
> > +  ///
> > +  EFI_GUID              DeviceType;
> 
> Do we still need DeviceType? Consumer can query the Handle to understand the
> device type.