Sample Code
Windows Driver Samples/ KMDF Power Framework (PoFx) Sample/ C++/ Driver/ SingleComp/ HwSim.c/
/*++ Copyright (c) Microsoft Corporation. All rights reserved. THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR PURPOSE. Module Name: HwSim.c Abstract: This module implements a simple hardware simulator that simulates reading of data from the device's components. In this sample, the "data" that is read is simply the bitwise complement of the component number. In other words, the data for component number 'X' is simply '~X'. The hardware simulator also verifies that when a component is read, the device is in D0 and the component is in F0. If not, it breaks into the debugger. Environment: Kernel mode --*/ #include "include.h" #include "HwSim.h" #include "HwSim.tmh" NTSTATUS HwSimInitialize( _In_ WDFDEVICE Device ) /*++ Routine Description: This routine initializes the hardware simulator Arguments: Device - Handle to the framework device object Return Value: An NTSTATUS value representing success or failure of the function. --*/ { NTSTATUS status; WDF_OBJECT_ATTRIBUTES objectAttributes; PHWSIM_CONTEXT devCtx; // // Allocate our context for this device // WDF_OBJECT_ATTRIBUTES_INIT_CONTEXT_TYPE(&objectAttributes, HWSIM_CONTEXT); status = WdfObjectAllocateContext((WDFOBJECT) Device, &objectAttributes, (PVOID*) &devCtx); if (FALSE == NT_SUCCESS(status)) { Trace(TRACE_LEVEL_ERROR, "%!FUNC! - WdfObjectAllocateContext failed with %!status!", status); goto exit; } devCtx->FirstD0Entry = TRUE; status = STATUS_SUCCESS; exit: return status; } VOID HwSimD0Entry( _In_ WDFDEVICE Device ) /*++ Routine Description: This routine simulates the device entering D0 Arguments: Device - Handle to the framework device object Return Value: None --*/ { PHWSIM_CONTEXT devCtx; devCtx = HwSimGetDeviceContext(Device); if (devCtx->FirstD0Entry) { devCtx->FirstD0Entry = FALSE; // // On the first D0 entry component is in F0 state // devCtx->ComponentFState = 0; } devCtx->DevicePoweredOn = TRUE; return; } VOID HwSimD0Exit( _In_ WDFDEVICE Device ) /*++ Routine Description: This routine simulates the device exiting D0 Arguments: Device - Handle to the framework device object Return Value: None --*/ { PHWSIM_CONTEXT devCtx; devCtx = HwSimGetDeviceContext(Device); devCtx->DevicePoweredOn = FALSE; return; } VOID HwSimFStateChange( _In_ WDFDEVICE Device, _In_ ULONG State ) /*++ Routine Description: This routine simulates a component changing its F-state Arguments: Device - Handle to the framework device object State - New F-state for the component Return Value: None --*/ { PHWSIM_CONTEXT devCtx; devCtx = HwSimGetDeviceContext(Device); // // Verify that the device is powered on // if (FALSE == devCtx->DevicePoweredOn) { // // This means that our driver is handling an F state transition while // device is not in D0. // Trace(TRACE_LEVEL_ERROR, "%!FUNC! - Expected device to be powered on, but it was not."); WdfVerifierDbgBreakPoint(); } ASSERT(devCtx->DevicePoweredOn); // // Put the component in the requested F-state // devCtx->ComponentFState = State; // // For an actual hardware, save any hardware state on Fx transition // and restore state on F0 transition. // return; } ULONG HwSimReadComponent( _In_ WDFDEVICE Device ) /*++ Routine Description: This routine simulates the reading of data from a component Arguments: Device - Handle to the framework device object Component - Component from which data is being read Return Value: A ULONG value representing the data that was read from the component --*/ { ULONG componentData; PHWSIM_CONTEXT devCtx; ULONG component = 0; devCtx = HwSimGetDeviceContext(Device); // // Verify that the device is powered on // if (FALSE == devCtx->DevicePoweredOn) { // // This means that our driver is attempting to read from the component // while the device is not powered on. // Trace(TRACE_LEVEL_ERROR, "%!FUNC! - Expected device to be powered on, but it was not."); WdfVerifierDbgBreakPoint(); } // // Verify that the component is in F0 // if (0 != devCtx->ComponentFState) { // // This means that our driver is attempting to read from the component // while the component is not in F0. // Trace(TRACE_LEVEL_ERROR, "%!FUNC! - Expected component to be in F0, but it was in F%d.", devCtx->ComponentFState); WdfVerifierDbgBreakPoint(); } ASSERT(devCtx->DevicePoweredOn); ASSERT(0 == devCtx->ComponentFState); // // In this sample, component data is just a bit-wise complement of the // component number. // componentData = ~component; return componentData; }
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