/*  This fix the problem that Efuse read error in high temperature condition. */
        /*  Designer says that there shall be some delay after ready bit is set, or the */
        /*  result will always stay on last data we read. */
-       rtw_udelay_os(50);
+       udelay(50);
        value32 = rtw_read32(Adapter, EFUSE_CTRL);
 
        *pbuf = (u8)(value32 & 0xff);
 
                                        if (value == (GET_PWR_CFG_VALUE(pwrcfgcmd) & GET_PWR_CFG_MASK(pwrcfgcmd)))
                                                poll_bit = true;
                                        else
-                                               rtw_udelay_os(10);
+                                               udelay(10);
 
                                        if (poll_count++ > max_poll_count) {
                                                DBG_88E("Fail to polling Offset[%#x]\n", offset);
                                break;
                        case PWR_CMD_DELAY:
                                if (GET_PWR_CFG_VALUE(pwrcfgcmd) == PWRSEQ_DELAY_US)
-                                       rtw_udelay_os(GET_PWR_CFG_OFFSET(pwrcfgcmd));
+                                       udelay(GET_PWR_CFG_OFFSET(pwrcfgcmd));
                                else
-                                       rtw_udelay_os(GET_PWR_CFG_OFFSET(pwrcfgcmd)*1000);
+                                       udelay(GET_PWR_CFG_OFFSET(pwrcfgcmd)*1000);
                                break;
                        case PWR_CMD_END:
                                /*  When this command is parsed, end the process */
 
 /*  ODM Timer relative API. */
 void ODM_StallExecution(u32 usDelay)
 {
-       rtw_udelay_os(usDelay);
+       udelay(usDelay);
 }
 
 void ODM_delay_ms(u32 ms)
 
 void ODM_delay_us(u32 us)
 {
-       rtw_udelay_os(us);
+       udelay(us);
 }
 
 void ODM_sleep_ms(u32 ms)
 
                        DBG_88E("%s: Polling FW ready success!! REG_MCUFWDL:0x%08x\n", __func__, value32);
                        return _SUCCESS;
                }
-               rtw_udelay_os(5);
+               udelay(5);
        } while (counter++ < POLLING_READY_TIMEOUT_COUNT);
 
        DBG_88E("%s: Polling FW ready fail!! REG_MCUFWDL:0x%08x\n", __func__, value32);
 
        tmplong2 = (tmplong2 & (~bLSSIReadAddress)) | (NewOffset<<23) | bLSSIReadEdge;  /* T65 RF */
 
        PHY_SetBBReg(Adapter, rFPGA0_XA_HSSIParameter2, bMaskDWord, tmplong&(~bLSSIReadEdge));
-       rtw_udelay_os(10);/*  PlatformStallExecution(10); */
+       udelay(10);/*  PlatformStallExecution(10); */
 
        PHY_SetBBReg(Adapter, pPhyReg->rfHSSIPara2, bMaskDWord, tmplong2);
-       rtw_udelay_os(100);/* PlatformStallExecution(100); */
+       udelay(100);/* PlatformStallExecution(100); */
 
-       rtw_udelay_os(10);/* PlatformStallExecution(10); */
+       udelay(10);/* PlatformStallExecution(10); */
 
        if (eRFPath == RF_PATH_A)
                RfPiEnable = (u8)PHY_QueryBBReg(Adapter, rFPGA0_XA_HSSIParameter1, BIT8);
 
                }
                /*----Set RF_ENV enable----*/
                PHY_SetBBReg(Adapter, pPhyReg->rfintfe, bRFSI_RFENV<<16, 0x1);
-               rtw_udelay_os(1);/* PlatformStallExecution(1); */
+               udelay(1);/* PlatformStallExecution(1); */
 
                /*----Set RF_ENV output high----*/
                PHY_SetBBReg(Adapter, pPhyReg->rfintfo, bRFSI_RFENV, 0x1);
-               rtw_udelay_os(1);/* PlatformStallExecution(1); */
+               udelay(1);/* PlatformStallExecution(1); */
 
                /* Set bit number of Address and Data for RF register */
                PHY_SetBBReg(Adapter, pPhyReg->rfHSSIPara2, b3WireAddressLength, 0x0);  /*  Set 1 to 4 bits for 8255 */
-               rtw_udelay_os(1);/* PlatformStallExecution(1); */
+               udelay(1);/* PlatformStallExecution(1); */
 
                PHY_SetBBReg(Adapter, pPhyReg->rfHSSIPara2, b3WireDataLength, 0x0);     /*  Set 0 to 12  bits for 8255 */
-               rtw_udelay_os(1);/* PlatformStallExecution(1); */
+               udelay(1);/* PlatformStallExecution(1); */
 
                /*----Initialize RF fom connfiguration file----*/
                switch (eRFPath) {
 
 
 u32  rtw_atoi(u8 *s);
 
-void rtw_udelay_os(int us);
-
 static inline unsigned char _cancel_timer_ex(struct timer_list *ptimer)
 {
        return del_timer_sync(ptimer);
 
                msleep((us/1000) + 1);
 }
 
-void rtw_udelay_os(int us)
-{
-       udelay((unsigned long)us);
-}
-
 #define RTW_SUSPEND_LOCK_NAME "rtw_wifi"
 
 static const struct device_type wlan_type = {