update rp2040 port

Author: hathach

examples/Composite/mouse_ramdisk/mouse_ramdisk.ino

@@ -31,11 +31,11 @@ uint8_t const desc_hid_report[] =
 Adafruit_USBD_HID usb_hid;
 Adafruit_USBD_MSC usb_msc;
 
-#if defined ARDUINO_SAMD_CIRCUITPLAYGROUND_EXPRESS
+#if defined ARDUINO_SAMD_CIRCUITPLAYGROUND_EXPRESS || defined ARDUINO_NRF52840_CIRCUITPLAY
   const int pin = 4; // Left Button
   bool activeState = true;
-#elif defined ARDUINO_NRF52840_FEATHER
-  const int pin = 7; // UserSw
+#elif defined PIN_BUTTON1
+  const int pin = PIN_BUTTON1;
   bool activeState = false;
 #else
   const int pin = 12;
@@ -128,4 +128,4 @@ int32_t msc_write_cb (uint32_t lba, uint8_t* buffer, uint32_t bufsize)
 void msc_flush_cb (void)
 {
   // nothing to do
-}
+}

src/arduino/Adafruit_TinyUSB_API.cpp

@@ -39,10 +39,13 @@ void TinyUSB_Device_Init(uint8_t rhport)
   USBDevice.begin(rhport);
 }
 
+// RP2040 has its own implementation since it needs mutex for dual core
+#ifndef ARDUINO_ARCH_RP2040
 void TinyUSB_Device_Task(void)
 {
-  USBDevice.task();
+  tud_task();
 }
+#endif
 
 void TinyUSB_Device_FlushCDC(void)
 {

src/arduino/Adafruit_TinyUSB_API.h

@@ -61,7 +61,7 @@ void TinyUSB_Device_FlushCDC(void) __attribute__((weak));
 void TinyUSB_Port_EnterDFU(void);
 
 // Init device hardware.
-// Called by USBDevice.begin()
+// Called by TinyUSB_Device_Init()
 void TinyUSB_Port_InitDevice(uint8_t rhport);
 
 // Get unique serial number, needed for Serial String Descriptor

src/arduino/ports/Adafruit_TinyUSB_rp2040.cpp

@@ -27,11 +27,15 @@
 #if defined ARDUINO_ARCH_RP2040 & TUSB_OPT_DEVICE_ENABLED
 
 #include "Arduino.h"
-#include "arduino/Adafruit_USBD_Device.h"
-
 #include "pico/bootrom.h"
+#include "pico/time.h"
+#include "hardware/irq.h"
+#include "pico/mutex.h"
 #include "pico/unique_id.h"
 
+#include "tusb.h"
+#include "arduino/Adafruit_TinyUSB_API.h"
+
 //--------------------------------------------------------------------+
 // Forward USB interrupt events to TinyUSB IRQ Handler
 // rp2040 implementation will install approriate handler when initializing
@@ -42,12 +46,40 @@
 // Porting API
 //--------------------------------------------------------------------+
 
+// USB processing will be a periodic timer task
+#define USB_TASK_INTERVAL 1000
+#define USB_TASK_IRQ 31
+
+// Big, global USB mutex, shared with all USB devices to make sure we don't
+// have multiple cores updating the TUSB state in parallel
+mutex_t __usb_mutex;
+
+static void usb_irq() {
+    // if the mutex is already owned, then we are in user code
+    // in this file which will do a tud_task itself, so we'll just do nothing
+    // until the next tick; we won't starve
+    if (mutex_try_enter(&__usb_mutex, NULL)) {
+        tud_task();
+        mutex_exit(&__usb_mutex);
+    }
+}
+
+static int64_t timer_task(__unused alarm_id_t id, __unused void *user_data) {
+    irq_set_pending(USB_TASK_IRQ);
+    return USB_TASK_INTERVAL;
+}
+
 void TinyUSB_Port_InitDevice(uint8_t rhport)
 {
   (void) rhport;
 
-  // no specific hardware initialization
-  // TOOD maybe set up sdtio usb
+  mutex_init(&__usb_mutex);
+  tusb_init();
+
+  irq_set_exclusive_handler(USB_TASK_IRQ, usb_irq);
+  irq_set_enabled(USB_TASK_IRQ, true);
+
+  add_alarm_in_us(USB_TASK_INTERVAL, timer_task, NULL, true);
 }
 
 void TinyUSB_Port_EnterDFU(void)
@@ -62,4 +94,25 @@ uint8_t TinyUSB_Port_GetSerialNumber(uint8_t serial_id[16])
   return PICO_UNIQUE_BOARD_ID_SIZE_BYTES;
 }
 
+//--------------------------------------------------------------------+
+// Core API
+// Implement Core API since rp2040 need mutex for calling tud_task in
+// IRQ context
+//--------------------------------------------------------------------+
+
+extern "C"
+{
+
+void TinyUSB_Device_Task(void)
+{
+  // Since tud_task() is also invoked in ISR, we need to get the mutex first
+  if (mutex_try_enter(&__usb_mutex, NULL))
+  {
+    tud_task();
+    mutex_exit(&__usb_mutex);
+  }
+}
+
+}
+
 #endif // USE_TINYUSB