Win CE5.0背光驱动
在大多2440开发板BSP中的SMDK2440/DRIVERS/backlite目录下一般都有背光驱动。在注册表中添加如下函数的时候，开机时确实可以打印"!!!!!!!!!!!! BACKLIGHT ON !!!!!!!!!!!!，如果没有操作大概1分钟后也可以打印!!!!!!!!!!!! BACKLIGHT OFF !!!!!!!!!!!!。但打印("!!!!!!!!!!!! BACKLIGHT OFF !!!!!!!!!!!!后，就算有触发事件（在触摸屏上点击，或者移动鼠标）也不会打印"!!!!!!!!!!!! BACKLIGHT ON !!!!!!!!!!!!。
[HKEY_LOCAL_MACHINE/Drivers/BuiltIn/BAK]
"Index"=dword:1
"Prefix"="BAK"
"Dll"="backlight.dll"
"Order"=dword:1
"IClass"="{A32942B7-920C-486b-B0E6-92A702A99B35}"
当你好好分析驱动中的以下这3个Event时：
g_evtSignal[0] = CreateEvent(NULL, FALSE, FALSE, szevtBacklightChange);
g_evtSignal[1] = CreateEvent(NULL, FALSE, FALSE, szevtUserInput);
g_evtSignal[BL_POWEREVT] = CreateEvent(NULL, FALSE, FALSE, szevtPowerChanged);
尤其是第二个，好像又没有问题。
其实这个驱动大体是正确的，只是当键盘鼠标或触摸屏输入时候gwes 发送“PowerManager/ActivityTimer/UserActivity” event，而不是原驱动中的“("UserInputEvent");”修改后的源程序如下（SMDK2440/DRIVERS/backlite目录下bak_hw.cpp文件）。
//
// Copyright (c) Microsoft Corporation. All rights reserved.
//
//
// Use of this source code is subject to the terms of the Microsoft end-user
// license agreement (EULA) under which you licensed this SOFTWARE PRODUCT.
// If you did not accept the terms of the EULA, you are not authorized to use
// this source code. For a copy of the EULA, please see the LICENSE.RTF on your
// install media.
//
/*
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.
*/
#include <windows.h>
#include <nkintr.h>
#include <pm.h>
#include "s2440.h"
#include <nkintr.h>
#include "oalintr.h"
#include "drv_glob.h"
#include "pmplatform.h"
#include "bak_hw.h"
// Globals
const TCHAR szevtBacklightChange[] = TEXT("BackLightChangeEvent");
const TCHAR szevtPowerChanged[] = TEXT("PowerChangedEvent");
const TCHAR szevtUserInput[] = TEXT("PowerManager/ActivityTimer/UserActivity");
const TCHAR szregRootKey[] = TEXT("ControlPanel//Backlight");
const TCHAR szregBatteryTimeout[] = TEXT("BatteryTimeout");
const TCHAR szregACTimeout[] = TEXT("ACTimeout");
const TCHAR szregBatteryAuto[] = TEXT("BacklightOnTap");
const TCHAR szregACAuto[] = TEXT("ACBacklightOnTap");
HANDLE g_evtSignal[NUM_EVENTS];
/* GPIO 寄存器对应的虚拟地址 */
volatile IOPreg * v_pIOPregs = (IOPreg * )IOP_BASE;
// Global structure
BLStruct g_BLInfo;
// Perform all one-time initialization of the backlight
//
BOOL
BacklightInitialize()
{
BOOL bRet = TRUE;
RETAILMSG(1, (TEXT("BacklightInitialize/r/n")));
BL_PowerOn(TRUE);
v_pIOPregs->rGPBCON &=0x3C03FF;
v_pIOPregs->rGPBCON |=0x15400;
v_pIOPregs->rGPBUP &=0x61F;
return bRet;
}
// Utility function to read from registry for the parameters
void BL_ReadRegistry(BLStruct *pBLInfo)
{
HKEY hKey;
LONG lResult;
DWORD dwType;
DWORD dwVal;
DWORD dwLen;
lResult = RegOpenKeyEx(HKEY_CURRENT_USER, szregRootKey, 0, KEY_ALL_ACCESS, &hKey);
if(ERROR_SUCCESS == lResult) {
dwType = REG_DWORD;
dwLen = sizeof(DWORD);
lResult = RegQueryValueEx(hKey, szregBatteryTimeout, NULL, &dwType,
(LPBYTE)&dwVal, &dwLen);
if(ERROR_SUCCESS == lResult) {
pBLInfo->m_dwBatteryTimeout = dwVal;
}
lResult = RegQueryValueEx(hKey, szregACTimeout, NULL, &dwType, (LPBYTE)&dwVal,
&dwLen);
if(ERROR_SUCCESS == lResult) {
pBLInfo->m_dwACTimeout = dwVal;
}
lResult = RegQueryValueEx(hKey, szregBatteryAuto, NULL, &dwType, (LPBYTE)&dwVal,
&dwLen);
if(ERROR_SUCCESS == lResult) {
pBLInfo->m_bBatteryAuto = (BOOL) dwVal;
}
lResult = RegQueryValueEx(hKey, szregACAuto, NULL, &dwType, (LPBYTE)&dwVal,
&dwLen);
if(ERROR_SUCCESS == lResult) {
pBLInfo->m_bACAuto = (BOOL) dwVal;
}
RegCloseKey(hKey);
}
else {
RETAILMSG(1, (TEXT("BAK : HKEY_CURRENT_USER//%s key doesn't exist!/r/n"), szregRootKey));
}
}
// uninitialize the backlight
void BL_Deinit()
{
int i;
RETAILMSG(1, (TEXT("BAK : BL_Deinit!/r/n")));
// Clean up
for(i=0; i<NUM_EVENTS; i++) {
if(g_evtSignal[i]) {
CloseHandle(g_evtSignal[i]);
}
}
}
//
// initialize the backlight
//
BOOL BL_Init()
{
// Set up all the events we need.
g_evtSignal[0] = CreateEvent(NULL, FALSE, FALSE, szevtBacklightChange);
g_evtSignal[1] = CreateEvent(NULL, FALSE, FALSE, szevtUserInput);
g_evtSignal[BL_POWEREVT] = CreateEvent(NULL, FALSE, FALSE, szevtPowerChanged);
if(!g_evtSignal[0] || !g_evtSignal[1] || !g_evtSignal[2]) {
BL_Deinit();
return FALSE;
}
DEBUGMSG (1,(TEXT("BL_Init() and SetGPIO/n/r")));
return TRUE;
}
//
// find out if AC power is plugged in
//
BOOL IsACOn()
{
// if (g_pDriverGlobals->power.ACLineStatus == AC_LINE_ONLINE)
// return TRUE;
// else
return FALSE;
}
//
// turn on/off the backlight
//
void BL_On(BOOL bOn)
{
if(bOn) {
if (g_BLInfo.m_dwStatus != BL_ON)
{
g_BLInfo.m_dwStatus = BL_ON;
v_pIOPregs->rGPBDAT&=0x6FF;//打开LED
RETAILMSG(1,(TEXT("!!!!!!!!!!!! BACKLIGHT ON !!!!!!!!!!!!/r/n")));
}
}
else {
if (g_BLInfo.m_dwStatus != BL_OFF)
{
g_BLInfo.m_dwStatus = BL_OFF;
v_pIOPregs->rGPBDAT|=0x100;//关闭LED
RETAILMSG(1,(TEXT("!!!!!!!!!!!! BACKLIGHT OFF !!!!!!!!!!!!/r/n")));
}
}
}
//
// restore power to the backlight
//
void BL_PowerOn(BOOL bInit)
{
//
// Add power-on GPIO register setting
//
BL_On(TRUE);
}
// The backlight handling is done by a thread, which monitors those
// three event and performs some actions based on the parameters specified
// in HKLM/ControlPanel/Backlight
//
// backlight service thread
//
DWORD BL_MonitorThread(PVOID pParms)
{
DWORD dwResult;
DWORD dwTimeout;
// Initialization stuff is here
//
// Initialize the events
// Initialize the BLInfo data structure
// Those are default values. Modify them if necessary
g_BLInfo.m_bACAuto = TRUE;
g_BLInfo.m_bBatteryAuto = TRUE;
g_BLInfo.m_dwBatteryTimeout = 20; // 20 Seconds
g_BLInfo.m_dwACTimeout = 60; // 1 minutes
// Now read from the registry to see what they say
BL_ReadRegistry(&g_BLInfo);
// Initialize BL
if(!BL_Init()) {
RETAILMSG(1, (TEXT("BL_Init() Failed! Exit from BL_MonitorThread!/r/n")));
return 0;
}
while(1) {
__try {
// If we are using AC now, use m_dwACTimeout as the timeout
// otherwise, use m_dwBatteryTimeout
if(IsACOn()) {
dwTimeout = g_BLInfo.m_dwACTimeout * 1000;
}
else {
dwTimeout = g_BLInfo.m_dwBatteryTimeout * 1000;
}
// However, if user wants BL on all the time, we have to let him
// do that. Or if we come back here, and BL is off, we want to
// put this thread to sleep until other event happens.
if(dwTimeout == 0 || g_BLInfo.m_dwStatus == BL_OFF) {
dwTimeout = INFINITE;
}
// Now let's wait for either there is an update on registry, or
// there is user action on the device, or there is activity on
// AC power supply.
dwResult = WaitForMultipleObjects(NUM_EVENTS, &g_evtSignal[0], FALSE, dwTimeout);
// If we are signaled by registry event
if(WAIT_OBJECT_0 == dwResult) {
// All we need to do is to read from registry and update the tick count
BL_ReadRegistry(&g_BLInfo);
RETAILMSG(1, (TEXT("BackLightChangeEvent! m_dwACTimeout=%d, m_dwBatteryTimeout=%d/r/n"),g_BLInfo.m_dwACTimeout,g_BLInfo.m_dwBatteryTimeout));
// Always turn on the Backlight after a change to registry
BL_On(TRUE);
}
else if(dwResult == WAIT_OBJECT_0+1) {
// User activity, depending on the situation, we may / may not update
// the tick count
//RETAILMSG(1, (TEXT("2...WAIT_OBJECT_0+1!/r/n")));
if(IsACOn()) {
if(g_BLInfo.m_bACAuto) {
// Turn on backlight
BL_On(TRUE);
}
}
else {
if(g_BLInfo.m_bBatteryAuto) {
BL_On(TRUE);
}
}
}
else if(dwResult == WAIT_OBJECT_0+2) {
// When AC is plugged or un-plugged, we don't really need to do anything
// We continue the loop. The correct timeout value will be assigned at
// the top of the while loop.
RETAILMSG(1, (TEXT("BackLight Thread: power changed!/r/n")));
}
else if(dwResult == WAIT_TIMEOUT) {
// Time out, let's turn the device off
RETAILMSG(1, (TEXT("Timeout, turn off the backlight!/r/n")));
BL_On(FALSE);
}
}
__except(EXCEPTION_EXECUTE_HANDLER){
// do nothing
RETAILMSG(1, (TEXT("an exception is raised in BL_MonitorThread... /r/n")));
}
}
}