debug 输出

#define DRV_DEBUG 1
#define DRV_DEBUG_DEBUG 0x0001
#define DRV_DEBUG_ERR 0x0002
#define DRV_DEBUG_ALL 0xFFFF

#if DRV_DEBUG
    static unsigned int drv_flags = DRV_DEBUG_DEBUG|DRV_DEBUG_ERR;
    #define DRV_PRINT(flag, fmt, ...) \
                do{\
                    if(drv_flags & flag){\
                    printf("[%24s : %4d] -- "fmt, __FUNCTION__, __LINE__, ##__VA_ARGS__);}\
                }while(0)
#else
        #define DRV_PRINT(fmt, ...)
#endif