SN32F24xB: Add remote wakeup and examples of suspend handling

os/hal/ports/SN32/LLD/SN32F24xB/USB/hal_usb_lld.c

@@ -213,6 +213,12 @@ static void usb_lld_serve_interrupt(USBDriver *usbp)
             /* Suspend */
             __USB_CLRINSTS(mskBUS_SUSPEND);
             _usb_suspend(usbp);
+            //USB suspend will put MCU in sleep mode with lower clock
+            //and disable execution of user code allowing only interrupt to execute
+            //keeping it here just for reference on how to could be done
+            //not necessary for remote wakeup to work
+            //uncomment if want to experiment with suspend mode
+            //USB_SuspendEvent();
         }
         else if(iwIntFlag & mskBUS_RESUME)
         {

os/hal/ports/SN32/LLD/SN32F24xB/USB/hal_usb_lld.h

@@ -28,6 +28,7 @@
 #if (HAL_USE_USB == TRUE) || defined(__DOXYGEN__)
 
 #include "sn32_usb.h"
+#include "usbhw.h"
 
 /*===========================================================================*/
 /* Driver constants.                                                         */
@@ -362,7 +363,9 @@ struct USBDriver {
  *
  * @notapi
  */
-#define usb_lld_wakeup_host(usbp)
+#define usb_lld_wakeup_host(usbp) { \
+    USB_RemoteWakeUp();             \
+}
 
 /*===========================================================================*/
 /* External declarations.                                                    */

os/hal/ports/SN32/LLD/SN32F24xB/USB/usbhw.c

@@ -362,3 +362,31 @@ void USB_WakeupEvent(void)
     __USB_CLRINSTS(mskBUS_WAKEUP);  //** Clear BUS_WAKEUP
 }
 
+/*****************************************************************************
+* Function      : USB_SuspendEvent
+* Description   : puts MCU in sleep mode
+* Input         : None
+* Output        : None
+* Return        : None
+* Note          : None
+*****************************************************************************/
+void USB_SuspendEvent(void)
+{
+    __USB_PHY_DISABLE;
+    SN_USB->INTEN = 0;
+    //** switch ILRC
+    SN_SYS0->CLKCFG = 0x01;
+    //** check ILRC status
+    while((SN_SYS0->CLKCFG & 0x10) != 0x10);
+    //** switch SYSCLK / 4 DO NOT set SYSCLK / 1 or SYSCLK / 2!!!!
+    SN_SYS0->AHBCP = 2;
+    //** disable IHRC
+    SN_SYS0->ANBCTRL = 0;
+    SN_USB->INTEN = (mskBUS_IE|mskUSB_IE|mskEPnACK_EN|mskBUSWK_IE);
+    SN_USB->INTEN |= mskEP1_NAK_EN;
+    SN_USB->INTEN |= mskEP2_NAK_EN;
+    SN_USB->INTEN |= mskEP3_NAK_EN;
+    SN_USB->INTEN |= mskEP4_NAK_EN;
+    SN_USB->INTEN |= mskUSB_SOF_IE;
+    SN_PMU->CTRL = 0x04;
+}

os/hal/ports/SN32/LLD/SN32F24xB/USB/usbhw.h

@@ -222,5 +222,6 @@ extern void USB_EPnBufferOffset(uint32_t wEPNum, uint32_t wAddr);
 extern void USB_ReturntoNormal(void);
 extern void USB_ResetEvent(void);
 extern void USB_WakeupEvent(void);
+extern void USB_SuspendEvent(void);
 
 #endif  /* __USBHW_H__ */