audk/MdeModulePkg/Universal/Console/ConPlatformDxe/ConPlatform.c

1025 lines
29 KiB
C

/** @file
Console Platform DXE Driver, install Console Device Guids and update Console
Environment Variables.
Copyright (c) 2006 - 2008, Intel Corporation. <BR>
All rights reserved. This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at
http://opensource.org/licenses/bsd-license.php
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
**/
#include "ConPlatform.h"
EFI_DRIVER_BINDING_PROTOCOL gConPlatformTextInDriverBinding = {
ConPlatformTextInDriverBindingSupported,
ConPlatformTextInDriverBindingStart,
ConPlatformTextInDriverBindingStop,
0xa,
NULL,
NULL
};
EFI_DRIVER_BINDING_PROTOCOL gConPlatformTextOutDriverBinding = {
ConPlatformTextOutDriverBindingSupported,
ConPlatformTextOutDriverBindingStart,
ConPlatformTextOutDriverBindingStop,
0xa,
NULL,
NULL
};
/**
Entrypoint of this module.
This function is the entrypoint of this module. It installs Driver Binding
Protocols together with Component Name Protocols.
@param ImageHandle The firmware allocated handle for the EFI image.
@param SystemTable A pointer to the EFI System Table.
@retval EFI_SUCCESS The entry point is executed successfully.
**/
EFI_STATUS
EFIAPI
InitializeConPlatform(
IN EFI_HANDLE ImageHandle,
IN EFI_SYSTEM_TABLE *SystemTable
)
{
EFI_STATUS Status;
Status = EfiLibInstallDriverBindingComponentName2 (
ImageHandle,
SystemTable,
&gConPlatformTextInDriverBinding,
ImageHandle,
&gConPlatformComponentName,
&gConPlatformComponentName2
);
ASSERT_EFI_ERROR (Status);
Status = EfiLibInstallDriverBindingComponentName2 (
ImageHandle,
SystemTable,
&gConPlatformTextOutDriverBinding,
NULL,
&gConPlatformComponentName,
&gConPlatformComponentName2
);
ASSERT_EFI_ERROR (Status);
return EFI_SUCCESS;
}
/**
Test to see if EFI_SIMPLE_TEXT_INPUT_PROTOCOL is supported on ControllerHandle.
@param This Protocol instance pointer.
@param ControllerHandle Handle of device to test.
@param RemainingDevicePath Optional parameter use to pick a specific child
device to start.
@retval EFI_SUCCESS This driver supports this device.
@retval other This driver does not support this device.
**/
EFI_STATUS
EFIAPI
ConPlatformTextInDriverBindingSupported (
IN EFI_DRIVER_BINDING_PROTOCOL *This,
IN EFI_HANDLE ControllerHandle,
IN EFI_DEVICE_PATH_PROTOCOL *RemainingDevicePath OPTIONAL
)
{
return ConPlatformDriverBindingSupported (
This,
ControllerHandle,
&gEfiSimpleTextInProtocolGuid
);
}
/**
Test to see if EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL is supported on ControllerHandle.
@param This Protocol instance pointer.
@param ControllerHandle Handle of device to test.
@param RemainingDevicePath Optional parameter use to pick a specific child
device to start.
@retval EFI_SUCCESS This driver supports this device.
@retval other This driver does not support this device.
**/
EFI_STATUS
EFIAPI
ConPlatformTextOutDriverBindingSupported (
IN EFI_DRIVER_BINDING_PROTOCOL *This,
IN EFI_HANDLE ControllerHandle,
IN EFI_DEVICE_PATH_PROTOCOL *RemainingDevicePath OPTIONAL
)
{
return ConPlatformDriverBindingSupported (
This,
ControllerHandle,
&gEfiSimpleTextOutProtocolGuid
);
}
/**
Test to see if the specified protocol is supported on ControllerHandle.
@param This Protocol instance pointer.
@param ControllerHandle Handle of device to test.
@param ProtocolGuid The specfic protocol.
@retval EFI_SUCCESS This driver supports this device.
@retval other This driver does not support this device.
**/
EFI_STATUS
ConPlatformDriverBindingSupported (
IN EFI_DRIVER_BINDING_PROTOCOL *This,
IN EFI_HANDLE ControllerHandle,
IN EFI_GUID *ProtocolGuid
)
{
EFI_STATUS Status;
VOID *Interface;
//
// Test to see if this is a physical device by checking if
// it has a Device Path Protocol.
//
Status = gBS->OpenProtocol (
ControllerHandle,
&gEfiDevicePathProtocolGuid,
NULL,
This->DriverBindingHandle,
ControllerHandle,
EFI_OPEN_PROTOCOL_TEST_PROTOCOL
);
if (EFI_ERROR (Status)) {
return Status;
}
//
// Test to see if this device supports the specified Protocol.
//
Status = gBS->OpenProtocol (
ControllerHandle,
ProtocolGuid,
(VOID **) &Interface,
This->DriverBindingHandle,
ControllerHandle,
EFI_OPEN_PROTOCOL_BY_DRIVER
);
if (EFI_ERROR (Status)) {
return Status;
}
gBS->CloseProtocol (
ControllerHandle,
ProtocolGuid,
This->DriverBindingHandle,
ControllerHandle
);
return EFI_SUCCESS;
}
/**
Start this driver on the device for console input.
Start this driver on ControllerHandle by opening Simple Text Input Protocol,
reading Device Path, and installing Console In Devcice GUID on ControllerHandle.
If this devcie is not one hot-plug devce, append its device path into the
console environment variables ConInDev.
@param This Protocol instance pointer.
@param ControllerHandle Handle of device to bind driver to
@param RemainingDevicePath Optional parameter use to pick a specific child
device to start.
@retval EFI_SUCCESS This driver is added to ControllerHandle
@retval EFI_ALREADY_STARTED This driver is already running on ControllerHandle
@retval other This driver does not support this device.
**/
EFI_STATUS
EFIAPI
ConPlatformTextInDriverBindingStart (
IN EFI_DRIVER_BINDING_PROTOCOL *This,
IN EFI_HANDLE ControllerHandle,
IN EFI_DEVICE_PATH_PROTOCOL *RemainingDevicePath
)
{
EFI_STATUS Status;
EFI_DEVICE_PATH_PROTOCOL *DevicePath;
EFI_SIMPLE_TEXT_INPUT_PROTOCOL *TextIn;
BOOLEAN IsInConInVariable;
//
// Get the Device Path Protocol so the environment variables can be updated
//
Status = gBS->OpenProtocol (
ControllerHandle,
&gEfiDevicePathProtocolGuid,
(VOID **) &DevicePath,
This->DriverBindingHandle,
ControllerHandle,
EFI_OPEN_PROTOCOL_GET_PROTOCOL
);
if (EFI_ERROR (Status)) {
return Status;
}
//
// Open the Simple Text Input Protocol BY_DRIVER
//
Status = gBS->OpenProtocol (
ControllerHandle,
&gEfiSimpleTextInProtocolGuid,
(VOID **) &TextIn,
This->DriverBindingHandle,
ControllerHandle,
EFI_OPEN_PROTOCOL_BY_DRIVER
);
if (EFI_ERROR (Status)) {
return Status;
}
//
// Check if the device path is in ConIn Variable
//
IsInConInVariable = FALSE;
Status = ConPlatformUpdateDeviceVariable (
L"ConIn",
DevicePath,
CHECK
);
if (!EFI_ERROR (Status)) {
IsInConInVariable = TRUE;
}
//
// Check the device path, if it is a hot plug device,
// do not put the device path into ConInDev, and install
// gEfiConsoleInDeviceGuid to the device handle directly.
// The policy is, make hot plug device plug in and play immediately.
//
if (IsHotPlugDevice (DevicePath)) {
gBS->InstallMultipleProtocolInterfaces (
&ControllerHandle,
&gEfiConsoleInDeviceGuid,
NULL,
NULL
);
//
// Append the device path to ConInDev only if it is in ConIn variable.
//
if (IsInConInVariable) {
ConPlatformUpdateDeviceVariable (
L"ConInDev",
DevicePath,
APPEND
);
}
} else {
//
// If it is not a hot-plug device, append the device path to the
// ConInDev environment variable
//
ConPlatformUpdateDeviceVariable (
L"ConInDev",
DevicePath,
APPEND
);
//
// If the device path is an instance in the ConIn environment variable,
// then install EfiConsoleInDeviceGuid onto ControllerHandle
//
if (IsInConInVariable) {
gBS->InstallMultipleProtocolInterfaces (
&ControllerHandle,
&gEfiConsoleInDeviceGuid,
NULL,
NULL
);
} else {
gBS->CloseProtocol (
ControllerHandle,
&gEfiSimpleTextInProtocolGuid,
This->DriverBindingHandle,
ControllerHandle
);
}
}
return EFI_SUCCESS;
}
/**
Start this driver on the device for console output and stardard error output.
Start this driver on ControllerHandle by opening Simple Text Output Protocol,
reading Device Path, and installing Console Out Devcic GUID, Standard Error
Device GUID on ControllerHandle.
If this devcie is not one hot-plug devce, append its device path into the
console environment variables ConOutDev, ErrOutDev.
@param This Protocol instance pointer.
@param ControllerHandle Handle of device to bind driver to
@param RemainingDevicePath Optional parameter use to pick a specific child
device to start.
@retval EFI_SUCCESS This driver is added to ControllerHandle
@retval EFI_ALREADY_STARTED This driver is already running on ControllerHandle
@retval other This driver does not support this device
**/
EFI_STATUS
EFIAPI
ConPlatformTextOutDriverBindingStart (
IN EFI_DRIVER_BINDING_PROTOCOL *This,
IN EFI_HANDLE ControllerHandle,
IN EFI_DEVICE_PATH_PROTOCOL *RemainingDevicePath
)
{
EFI_STATUS Status;
EFI_DEVICE_PATH_PROTOCOL *DevicePath;
EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL *TextOut;
BOOLEAN NeedClose;
BOOLEAN IsInConOutVariable;
BOOLEAN IsInErrOutVariable;
NeedClose = TRUE;
//
// Get the Device Path Protocol so the environment variables can be updated
//
Status = gBS->OpenProtocol (
ControllerHandle,
&gEfiDevicePathProtocolGuid,
(VOID **) &DevicePath,
This->DriverBindingHandle,
ControllerHandle,
EFI_OPEN_PROTOCOL_GET_PROTOCOL
);
if (EFI_ERROR (Status)) {
return Status;
}
//
// Open the Simple Text Output Protocol BY_DRIVER
//
Status = gBS->OpenProtocol (
ControllerHandle,
&gEfiSimpleTextOutProtocolGuid,
(VOID **) &TextOut,
This->DriverBindingHandle,
ControllerHandle,
EFI_OPEN_PROTOCOL_BY_DRIVER
);
if (EFI_ERROR (Status)) {
return Status;
}
//
// Check if the device path is in ConOut & ErrOut Variable
//
IsInConOutVariable = FALSE;
Status = ConPlatformUpdateDeviceVariable (
L"ConOut",
DevicePath,
CHECK
);
if (!EFI_ERROR (Status)) {
IsInConOutVariable = TRUE;
}
IsInErrOutVariable = FALSE;
Status = ConPlatformUpdateDeviceVariable (
L"ErrOut",
DevicePath,
CHECK
);
if (!EFI_ERROR (Status)) {
IsInErrOutVariable = TRUE;
}
//
// Check the device path, if it is a hot plug device,
// do not put the device path into ConOutDev and ErrOutDev,
// and install gEfiConsoleOutDeviceGuid to the device handle directly.
// The policy is, make hot plug device plug in and play immediately.
//
if (IsHotPlugDevice (DevicePath)) {
gBS->InstallMultipleProtocolInterfaces (
&ControllerHandle,
&gEfiConsoleOutDeviceGuid,
NULL,
NULL
);
//
// Append the device path to ConOutDev only if it is in ConOut variable.
//
if (IsInConOutVariable) {
ConPlatformUpdateDeviceVariable (
L"ConOutDev",
DevicePath,
APPEND
);
}
//
// Append the device path to ErrOutDev only if it is in ErrOut variable.
//
if (IsInErrOutVariable) {
ConPlatformUpdateDeviceVariable (
L"ErrOutDev",
DevicePath,
APPEND
);
}
} else {
//
// If it is not a hot-plug device, first append the device path to the
// ConOutDev environment variable
//
ConPlatformUpdateDeviceVariable (
L"ConOutDev",
DevicePath,
APPEND
);
//
// Then append the device path to the ErrOutDev environment variable
//
ConPlatformUpdateDeviceVariable (
L"ErrOutDev",
DevicePath,
APPEND
);
//
// If the device path is an instance in the ConOut environment variable,
// then install EfiConsoleOutDeviceGuid onto ControllerHandle
//
if (IsInConOutVariable) {
NeedClose = FALSE;
Status = gBS->InstallMultipleProtocolInterfaces (
&ControllerHandle,
&gEfiConsoleOutDeviceGuid,
NULL,
NULL
);
}
//
// If the device path is an instance in the ErrOut environment variable,
// then install EfiStandardErrorDeviceGuid onto ControllerHandle
//
if (IsInErrOutVariable) {
NeedClose = FALSE;
gBS->InstallMultipleProtocolInterfaces (
&ControllerHandle,
&gEfiStandardErrorDeviceGuid,
NULL,
NULL
);
}
if (NeedClose) {
gBS->CloseProtocol (
ControllerHandle,
&gEfiSimpleTextOutProtocolGuid,
This->DriverBindingHandle,
ControllerHandle
);
}
}
return EFI_SUCCESS;
}
/**
Stop this driver on ControllerHandle by removing Console In Devcice GUID
and closing the Simple Text Input protocol on ControllerHandle.
@param This Protocol instance pointer.
@param ControllerHandle Handle of device to stop driver on
@param NumberOfChildren Number of Handles in ChildHandleBuffer. If number of
children is zero stop the entire bus driver.
@param ChildHandleBuffer List of Child Handles to Stop.
@retval EFI_SUCCESS This driver is removed ControllerHandle
@retval other This driver was not removed from this device
**/
EFI_STATUS
EFIAPI
ConPlatformTextInDriverBindingStop (
IN EFI_DRIVER_BINDING_PROTOCOL *This,
IN EFI_HANDLE ControllerHandle,
IN UINTN NumberOfChildren,
IN EFI_HANDLE *ChildHandleBuffer
)
{
EFI_STATUS Status;
EFI_DEVICE_PATH_PROTOCOL *DevicePath;
//
// Get the Device Path Protocol firstly
//
Status = gBS->OpenProtocol (
ControllerHandle,
&gEfiDevicePathProtocolGuid,
(VOID **) &DevicePath,
This->DriverBindingHandle,
ControllerHandle,
EFI_OPEN_PROTOCOL_GET_PROTOCOL
);
//
// If there is device path on ControllerHandle
//
if (!EFI_ERROR (Status)) {
//
// Remove DevicePath from ConInDev if exists.
//
ConPlatformUpdateDeviceVariable (
L"ConInDev",
DevicePath,
DELETE
);
}
//
// Uninstall the Console Device GUIDs from Controller Handle
//
ConPlatformUnInstallProtocol (
This,
ControllerHandle,
&gEfiConsoleInDeviceGuid
);
//
// Close the Simple Text Input Protocol
//
gBS->CloseProtocol (
ControllerHandle,
&gEfiSimpleTextInProtocolGuid,
This->DriverBindingHandle,
ControllerHandle
);
return EFI_SUCCESS;
}
/**
Stop this driver on ControllerHandle by removing Console Out Devcice GUID
and closing the Simple Text Output protocol on ControllerHandle.
@param This Protocol instance pointer.
@param ControllerHandle Handle of device to stop driver on
@param NumberOfChildren Number of Handles in ChildHandleBuffer. If number of
children is zero stop the entire bus driver.
@param ChildHandleBuffer List of Child Handles to Stop.
@retval EFI_SUCCESS This driver is removed ControllerHandle
@retval other This driver was not removed from this device
**/
EFI_STATUS
EFIAPI
ConPlatformTextOutDriverBindingStop (
IN EFI_DRIVER_BINDING_PROTOCOL *This,
IN EFI_HANDLE ControllerHandle,
IN UINTN NumberOfChildren,
IN EFI_HANDLE *ChildHandleBuffer
)
{
EFI_STATUS Status;
EFI_DEVICE_PATH_PROTOCOL *DevicePath;
//
// Get the Device Path Protocol firstly
//
Status = gBS->OpenProtocol (
ControllerHandle,
&gEfiDevicePathProtocolGuid,
(VOID **) &DevicePath,
This->DriverBindingHandle,
ControllerHandle,
EFI_OPEN_PROTOCOL_GET_PROTOCOL
);
if (!EFI_ERROR (Status)) {
//
// Remove DevicePath from ConOutDev and ErrOutDev if exists.
//
ConPlatformUpdateDeviceVariable (
L"ConOutDev",
DevicePath,
DELETE
);
ConPlatformUpdateDeviceVariable (
L"ErrOutDev",
DevicePath,
DELETE
);
}
//
// Uninstall the Console Device GUIDs from Controller Handle
//
ConPlatformUnInstallProtocol (
This,
ControllerHandle,
&gEfiConsoleOutDeviceGuid
);
ConPlatformUnInstallProtocol (
This,
ControllerHandle,
&gEfiStandardErrorDeviceGuid
);
//
// Close the Simple Text Output Protocol
//
gBS->CloseProtocol (
ControllerHandle,
&gEfiSimpleTextOutProtocolGuid,
This->DriverBindingHandle,
ControllerHandle
);
return EFI_SUCCESS;
}
/**
Uninstall the specified protocol.
@param This Protocol instance pointer.
@param Handle Handle of device to uninstall protocol on.
@param ProtocolGuid The specified protocol need to be uninstalled.
**/
VOID
ConPlatformUnInstallProtocol (
IN EFI_DRIVER_BINDING_PROTOCOL *This,
IN EFI_HANDLE Handle,
IN EFI_GUID *ProtocolGuid
)
{
EFI_STATUS Status;
Status = gBS->OpenProtocol (
Handle,
ProtocolGuid,
NULL,
This->DriverBindingHandle,
Handle,
EFI_OPEN_PROTOCOL_TEST_PROTOCOL
);
if (!EFI_ERROR (Status)) {
gBS->UninstallMultipleProtocolInterfaces (
Handle,
ProtocolGuid,
NULL,
NULL
);
}
return ;
}
/**
Get the necessary size of buffer and read the variable.
First get the necessary size of buffer. Then read the
EFI variable (Name) and return a dynamically allocated
buffer. On failure return NULL.
@param Name String part of EFI variable name
@return Dynamically allocated memory that contains a copy of the EFI variable.
Caller is repsoncible freeing the buffer. Return NULL means Variable
was not read.
**/
VOID *
ConPlatformGetVariable (
IN CHAR16 *Name
)
{
EFI_STATUS Status;
VOID *Buffer;
UINTN BufferSize;
BufferSize = 0;
Buffer = NULL;
//
// Test to see if the variable exists. If it doesn't, return NULL.
//
Status = gRT->GetVariable (
Name,
&gEfiGlobalVariableGuid,
NULL,
&BufferSize,
Buffer
);
if (Status == EFI_BUFFER_TOO_SMALL) {
//
// Allocate the buffer to return
//
Buffer = AllocatePool (BufferSize);
if (Buffer == NULL) {
return NULL;
}
//
// Read variable into the allocated buffer.
//
Status = gRT->GetVariable (
Name,
&gEfiGlobalVariableGuid,
NULL,
&BufferSize,
Buffer
);
if (EFI_ERROR (Status)) {
FreePool (Buffer);
//
// To make sure Buffer is NULL if any error occurs.
//
Buffer = NULL;
}
}
return Buffer;
}
/**
Function compares a device path data structure to that of all the nodes of a
second device path instance.
@param Multi A pointer to a multi-instance device path data structure.
@param Single A pointer to a single-instance device path data structure.
@param NewDevicePath If Delete is TRUE, this parameter must not be null, and it
points to the remaining device path data structure.
(remaining device path = Multi - Single.)
@param Delete If TRUE, means removing Single from Multi.
If FALSE, the routine just check whether Single matches
with any instance in Multi.
@retval EFI_SUCCESS If the Single is contained within Multi.
@retval EFI_NOT_FOUND If the Single is not contained within Multi.
@retval EFI_INVALID_PARAMETER Multi is NULL.
@retval EFI_INVALID_PARAMETER Single is NULL.
@retval EFI_INVALID_PARAMETER NewDevicePath is NULL when Delete is TRUE.
**/
EFI_STATUS
ConPlatformMatchDevicePaths (
IN EFI_DEVICE_PATH_PROTOCOL *Multi,
IN EFI_DEVICE_PATH_PROTOCOL *Single,
OUT EFI_DEVICE_PATH_PROTOCOL **NewDevicePath OPTIONAL,
IN BOOLEAN Delete
)
{
EFI_DEVICE_PATH_PROTOCOL *DevicePath;
EFI_DEVICE_PATH_PROTOCOL *TempDevicePath1;
EFI_DEVICE_PATH_PROTOCOL *TempDevicePath2;
EFI_DEVICE_PATH_PROTOCOL *DevicePathInst;
UINTN Size;
//
// The passed in DevicePath should not be NULL
//
if ((Multi == NULL) || (Single == NULL)) {
return EFI_INVALID_PARAMETER;
}
//
// If performing Delete operation, the NewDevicePath must not be NULL.
//
if (Delete) {
if (NewDevicePath == NULL) {
return EFI_INVALID_PARAMETER;
}
}
TempDevicePath1 = NULL;
DevicePath = Multi;
DevicePathInst = GetNextDevicePathInstance (&DevicePath, &Size);
//
// Search for the match of 'Single' in 'Multi'
//
while (DevicePathInst != NULL) {
if (CompareMem (Single, DevicePathInst, Size) == 0) {
if (!Delete) {
//
// If Delete is FALSE, return EFI_SUCCESS if Single is found in Multi.
//
FreePool (DevicePathInst);
return EFI_SUCCESS;
}
} else {
if (Delete) {
//
// If the node of Multi does not match Single, then added it back to the result.
// That is, the node matching Single will be dropped and deleted from result.
//
TempDevicePath2 = AppendDevicePathInstance (
TempDevicePath1,
DevicePathInst
);
if (TempDevicePath1 != NULL) {
FreePool (TempDevicePath1);
}
TempDevicePath1 = TempDevicePath2;
}
}
FreePool (DevicePathInst);
DevicePathInst = GetNextDevicePathInstance (&DevicePath, &Size);
}
if (Delete) {
//
// Return the new device path data structure with specified node deleted.
//
*NewDevicePath = TempDevicePath1;
return EFI_SUCCESS;
}
return EFI_NOT_FOUND;
}
/**
Update console environment variables.
@param VariableName Console environment variables, ConOutDev, ConInDev
ErrOutDev, ConIn ,ConOut or ErrOut.
@param DevicePath Console devcie's device path.
@param Operation Variable operations, including APPEND, CHECK and DELETE.
@retval EFI_SUCCESS Variable operates successfully.
@retval EFI_OUT_OF_RESOURCES If variable cannot be appended.
@retval other Variable updating failed.
**/
EFI_STATUS
ConPlatformUpdateDeviceVariable (
IN CHAR16 *VariableName,
IN EFI_DEVICE_PATH_PROTOCOL *DevicePath,
IN CONPLATFORM_VAR_OPERATION Operation
)
{
EFI_STATUS Status;
EFI_DEVICE_PATH_PROTOCOL *VariableDevicePath;
EFI_DEVICE_PATH_PROTOCOL *NewVariableDevicePath;
VariableDevicePath = NULL;
NewVariableDevicePath = NULL;
//
// Get Variable according to variable name.
// The memory for Variable is allocated within ConPlatformGetVarible(),
// it is the caller's responsibility to free the memory before return.
//
VariableDevicePath = ConPlatformGetVariable (VariableName);
if (Operation != DELETE) {
//
// Match specified DevicePath in Console Variable.
//
Status = ConPlatformMatchDevicePaths (
VariableDevicePath,
DevicePath,
NULL,
FALSE
);
if ((Operation == CHECK) || (!EFI_ERROR (Status))) {
//
// Branch here includes 2 cases:
// 1. Operation is CHECK, simply return Status.
// 2. Operation is APPEND, and device path already exists in variable, also return.
//
if (VariableDevicePath != NULL) {
FreePool (VariableDevicePath);
}
return Status;
}
//
// We reach here to append a device path that does not exist in variable.
//
Status = EFI_SUCCESS;
NewVariableDevicePath = AppendDevicePathInstance (
VariableDevicePath,
DevicePath
);
if (NewVariableDevicePath == NULL) {
Status = EFI_OUT_OF_RESOURCES;
}
} else {
//
// We reach here to remove DevicePath from the environment variable that
// is a multi-instance device path.
//
Status = ConPlatformMatchDevicePaths (
VariableDevicePath,
DevicePath,
&NewVariableDevicePath,
TRUE
);
}
if (VariableDevicePath != NULL) {
FreePool (VariableDevicePath);
}
if (EFI_ERROR (Status)) {
return Status;
}
if (NewVariableDevicePath != NULL) {
//
// Update Console Environment Variable.
//
Status = gRT->SetVariable (
VariableName,
&gEfiGlobalVariableGuid,
EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS,
GetDevicePathSize (NewVariableDevicePath),
NewVariableDevicePath
);
FreePool (NewVariableDevicePath);
}
return Status;
}
/**
Check if the device supports hot-plug through its device path.
This function could be updated to check more types of Hot Plug devices.
Currently, it checks USB and PCCard device.
@param DevicePath Pointer to device's device path.
@retval TRUE The devcie is a hot-plug device
@retval FALSE The devcie is not a hot-plug device.
**/
BOOLEAN
IsHotPlugDevice (
IN EFI_DEVICE_PATH_PROTOCOL *DevicePath
)
{
EFI_DEVICE_PATH_PROTOCOL *CheckDevicePath;
CheckDevicePath = DevicePath;
while (!IsDevicePathEnd (CheckDevicePath)) {
//
// Check device whether is hot plug device or not throught Device Path
//
if ((DevicePathType (CheckDevicePath) == MESSAGING_DEVICE_PATH) &&
(DevicePathSubType (CheckDevicePath) == MSG_USB_DP ||
DevicePathSubType (CheckDevicePath) == MSG_USB_CLASS_DP ||
DevicePathSubType (CheckDevicePath) == MSG_USB_WWID_DP)) {
//
// If Device is USB device
//
return TRUE;
}
if ((DevicePathType (CheckDevicePath) == HARDWARE_DEVICE_PATH) &&
(DevicePathSubType (CheckDevicePath) == HW_PCCARD_DP)) {
//
// If Device is PCCard
//
return TRUE;
}
CheckDevicePath = NextDevicePathNode (CheckDevicePath);
}
return FALSE;
}