rp2040 add disconnection detection

- also use dcd_event_bus_reset()
- Add TODO for suspend, resume later on (need to test with/without vbus
detection).

src/device/usbd.c

@@ -992,11 +992,15 @@ void dcd_event_handler(dcd_event_t const * event, bool in_isr)
   switch (event->event_id)
   {
     case DCD_EVENT_UNPLUGGED:
+      // UNPLUGGED event can be bouncing, only processing if we are currently connected
+      if ( _usbd_dev.connected )
+      {
         _usbd_dev.connected  = 0;
         _usbd_dev.addressed  = 0;
         _usbd_dev.cfg_num    = 0;
         _usbd_dev.suspended  = 0;
         osal_queue_send(_usbd_q, event, in_isr);
+      }
     break;
 
     case DCD_EVENT_SOF:
@@ -1004,9 +1008,10 @@ void dcd_event_handler(dcd_event_t const * event, bool in_isr)
     break;
 
     case DCD_EVENT_SUSPEND:
-      // NOTE: When plugging/unplugging device, the D+/D- state are unstable and can accidentally meet the
+      // NOTE: When plugging/unplugging device, the D+/D- state are unstable and
-      // SUSPEND condition ( Idle for 3ms ). Some MCUs such as SAMD doesn't distinguish suspend vs disconnect as well.
+      // can accidentally meet the SUSPEND condition ( Bus Idle for 3ms ).
-      // We will skip handling SUSPEND/RESUME event if not currently connected
+      // In addition, some MCUs such as SAMD or boards that haven no VBUS detection cannot distinguish
+      // suspended vs disconnected. We will skip handling SUSPEND/RESUME event if not currently connected
       if ( _usbd_dev.connected )
       {
         _usbd_dev.suspended = 1;

src/portable/raspberrypi/rp2040/dcd_rp2040.c

@@ -317,13 +317,45 @@ static void dcd_rp2040_irq(void)
         pico_trace("BUS RESET (addr %d -> %d)\n", assigned_address, 0);
         usb_hw->dev_addr_ctrl = 0;
         handled |= USB_INTS_BUS_RESET_BITS;
-        dcd_event_bus_signal(0, DCD_EVENT_BUS_RESET, true);
+        dcd_event_bus_reset(0, TUSB_SPEED_FULL, true);
         usb_hw_clear->sie_status = USB_SIE_STATUS_BUS_RESET_BITS;
 #if TUD_OPT_RP2040_USB_DEVICE_ENUMERATION_FIX
         rp2040_usb_device_enumeration_fix();
 #endif
     }
 
+    if (status & USB_INTS_DEV_CONN_DIS_BITS)
+    {
+        handled |= USB_INTS_DEV_CONN_DIS_BITS;
+
+        if ( usb_hw->sie_status & USB_SIE_STATUS_CONNECTED_BITS )
+        {
+          // Connected: nothing to do
+        }else
+        {
+          // Disconnected
+          dcd_event_bus_signal(0, DCD_EVENT_UNPLUGGED, true);
+        }
+
+        usb_hw_clear->sie_status = USB_SIE_STATUS_CONNECTED_BITS;
+    }
+
+#if 0 // TODO Enable SUSPEND & RESUME interrupt and test later on with/without VBUS detection
+    if (status & USB_INTS_DEV_SUSPEND_BITS)
+    {
+        handled |= USB_INTS_DEV_SUSPEND_BITS;
+        dcd_event_bus_signal(0, DCD_EVENT_SUSPEND, true);
+        usb_hw_clear->sie_status = USB_SIE_STATUS_SUSPENDED_BITS;
+    }
+
+    if (status & USB_INTS_DEV_RESUME_FROM_HOST_BITS)
+    {
+        handled |= USB_INTS_DEV_RESUME_FROM_HOST_BITS;
+        dcd_event_bus_signal(0, DCD_EVENT_RESUME, true);
+        usb_hw_clear->sie_status = USB_SIE_STATUS_RESUME_BITS;
+    }
+#endif
+
     if (status ^ handled)
     {
         panic("Unhandled IRQ 0x%x\n", (uint) (status ^ handled));
@@ -364,8 +396,10 @@ void dcd_init (uint8_t rhport)
 
     // Enable individual controller IRQS here. Processor interrupt enable will be used
     // for the global interrupt enable...
+    // TODO Enable SUSPEND & RESUME interrupt
     usb_hw->sie_ctrl = USB_SIE_CTRL_EP0_INT_1BUF_BITS; 
-    usb_hw->inte     = USB_INTS_BUFF_STATUS_BITS | USB_INTS_BUS_RESET_BITS | USB_INTS_SETUP_REQ_BITS;
+    usb_hw->inte     = USB_INTS_BUFF_STATUS_BITS | USB_INTS_BUS_RESET_BITS | USB_INTS_SETUP_REQ_BITS |
+                       USB_INTS_DEV_CONN_DIS_BITS /* | USB_INTS_DEV_SUSPEND_BITS | USB_INTS_DEV_RESUME_FROM_HOST_BITS */  ;
 
     dcd_connect(rhport);
 }
@@ -393,8 +427,9 @@ void dcd_set_address (uint8_t rhport, uint8_t dev_addr)
 
 void dcd_remote_wakeup(uint8_t rhport)
 {
-    pico_info("dcd_remote_wakeup %d is not supported yet\n", rhport);
+    pico_info("dcd_remote_wakeup %d\n", rhport);
     assert(rhport == 0);
+    usb_hw_set->sie_ctrl = USB_SIE_CTRL_RESUME_BITS;
 }
 
 // disconnect by disabling internal pull-up resistor on D+/D-
@@ -402,6 +437,7 @@ void dcd_disconnect(uint8_t rhport)
 {
     pico_info("dcd_disconnect %d\n", rhport);
     assert(rhport == 0);
+    //TU_LOG2("dcd_disconnect\n");
     usb_hw_clear->sie_ctrl = USB_SIE_CTRL_PULLUP_EN_BITS;
 }
 
@@ -410,6 +446,7 @@ void dcd_connect(uint8_t rhport)
 {
     pico_info("dcd_connect %d\n", rhport);
     assert(rhport == 0);
+    //TU_LOG2("dcd_connect\n");
     usb_hw_set->sie_ctrl = USB_SIE_CTRL_PULLUP_EN_BITS;
 }