在google remote中，android接收端接收socket发来的IR CODE，然后将IR CODE模拟出来发给系统处理，这就是google remote接收端的原理。
系统端怎样模拟input event呢？
方法一：通过Instrumentation.sendKeyDownUpSync 实现，简单使用但是问题在于sendKeyDownUpSync发出的event，无法运行到
interceptKeyBeforeDispatching，也就无法正常作用 HOME，VOL...
方法二：通过uinput桥接；原理是利用内核现有的uinput驱动，通过内核驱动uinput来发送input event，而且还容易使用kl,kcm 客制化；
经过比较方法二较优，下面就就给出方法二的测试代码...
1、main函数，setup_uinput_device 完成设备的注册，然后创建一个线程 VirtualInputDev_EventThread，该线程重复发出keycode；
int main()
{
printf("Enter process !!!! n");
stVirtualInputDevData *pKpdData = (stVirtualInputDevData*) malloc(sizeof(stVirtualInputDevData));
pKpdData->min_keycode = umin_keycode;
pKpdData->max_keycode = umax_keycode;
if (setup_uinput_device(pKpdData) < 0) {
printf("Unable to find uInput devicen");
free(pKpdData);
return -1;
}
pthread_attr_t attr;
pthread_attr_init(&attr);
pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
if (0 != pthread_create(&keypad_EventThreadId, &attr, VirtualInputDev_EventThread, (void *)0)) {
printf("Create KeypadEventThread Failed!!n");
exit(1);
}
// Coverity server need set to ignore this.
while (1) {
usleep(1000000); // sleep 1 second
}
free(pKpdData);
pKpdData = 0;
// Destroy the device
ioctl(uinp_fd, UI_DEV_DESTROY);
close(uinp_fd);
return 0;
}
2、setup_uinput_device函数，完成设备注册；可以看到是直接打开uinput节点，设置了虚拟设备的name，verdor，product，bustype，
最后通过ioctl(uinp_fd, UI_DEV_CREATE)注册设备
int setup_uinput_device(stVirtualInputDevData* mstVirtualInputDevData)
{
struct uinput_user_dev uinp; // uInput device structure
int i;
// Open the input device
uinp_fd = open("/dev/uinput", O_WRONLY | O_NDELAY);
if (uinp_fd == 0) {
printf("Unable to open /dev/uinputn");
return -1;
}
// Intialize the uInput device to NULL
memset(&uinp, 0x00, sizeof(uinp));
strncpy(uinp.name, "virtualinputdev", sizeof(uinp.name)-1);
uinp.id.vendor = 0x1341;
uinp.id.product = 0x0001;
uinp.id.bustype = BUS_VIRTUAL;
// Keyboard
ioctl(uinp_fd, UI_SET_EVBIT, EV_KEY);
for (i = mstVirtualInputDevData->min_keycode; i < mstVirtualInputDevData->max_keycode; i++) {
ioctl(uinp_fd, UI_SET_KEYBIT, i);
}
// Create input device into input sub-system
if (write(uinp_fd, &uinp, sizeof(uinp)) != sizeof(uinp)) {
printf("First write returned fail.n");
return -1;
}
if (ioctl(uinp_fd, UI_DEV_CREATE)) {
printf("ioctl UI_DEV_CREATE returned fail.n");
return -1;
}
return 1;
}
3、线程 VirtualInputDev_EventThread，只是重复发key，发key是通过write_event_to_device来完成的
static void* VirtualInputDev_EventThread(void *driver_data)
{
unsigned char u8Keycode,i=umin_keycode;
while (1) {
u8Keycode = 0xff;
/* sleep an interval time */
usleep(2000000);//sleep 5 s
/* fill event to uinput device. */
write_event_to_device(i++, 0);
if(i==4){
i = 0;
}
printf ("virtualinputdev thread ...n");
//i %= umax_keycode;
}
printf ("virtualinputdev thread diedn");
pthread_exit(0);
return 0;
}
4、write_event_to_device 写event到uinput节点
void write_event_to_device(unsigned char u8KeyCode, unsigned char u8Repeat)
{
struct input_event event; // Input device structure
struct timespec s;
s.tv_nsec = 5000000L;
s.tv_sec = 0;
memset(&event, 0x00, sizeof(event));
gettimeofday(&event.time, 0);
event.type = EV_KEY;
event.code = u8KeyCode;
event.value = 1;
write(uinp_fd, &event, sizeof(event));
memset(&event, 0x00, sizeof(event));
gettimeofday(&event.time, 0);
event.type = EV_KEY;
event.code = u8KeyCode;
event.value = 0;
write(uinp_fd, &event, sizeof(event));
memset(&event, 0x00, sizeof(event));
gettimeofday(&event.time, 0);
event.type = EV_SYN;
event.code = SYN_REPORT;
event.value = 0;
write(uinp_fd, &event, sizeof(event));
}