[components][rtc] Add microsecond resolution support with RTC framework V2.0

Author: iysheng

components/drivers/include/drivers/rtc_core.h

@@ -27,6 +27,8 @@ struct rt_rtc_ops
     rt_err_t (*set_secs)(void *arg);
     rt_err_t (*get_alarm)(void *arg);
     rt_err_t (*set_alarm)(void *arg);
+    rt_err_t (*get_usecs)(void *arg);
+    rt_err_t (*set_usecs)(void *arg);
 };
 
 typedef struct rt_rtc_device

components/drivers/rtc/rtc_core.c

@@ -61,6 +61,12 @@ static rt_err_t rt_rtc_core_control(struct rt_device *dev,
         case RT_DEVICE_CTRL_RTC_SET_TIME:
             ret = TRY_DO_RTC_FUNC(rtc_core, set_secs, args);
             break;
+        case RT_DEVICE_CTRL_RTC_GET_TIME_US:
+            ret = TRY_DO_RTC_FUNC(rtc_core, get_usecs, args);
+            break;
+        case RT_DEVICE_CTRL_RTC_SET_TIME_US:
+            ret = TRY_DO_RTC_FUNC(rtc_core, set_usecs, args);
+            break;
         case RT_DEVICE_CTRL_RTC_GET_ALARM:
             ret = TRY_DO_RTC_FUNC(rtc_core, get_alarm, args);
             break;