- ACM fixed, thread added, wakeup() removed

class/acm.c

@@ -9,12 +9,15 @@
 #include "acm.h"
 
 #include <memory.h>
+#include <stdint.h>
 #include <string.h>
 
 #include "../usb.h"
 #include "../usb_device_types.h"
+#include "cmsis_os2.h"
 
 #include <blocking_io/blocking_fifo.h>
+#include <strings.h>
 
 // -------------------------
 
@@ -22,6 +25,42 @@ static Usb_AcmState acms = {0};                 ///< ACM module state
 static uint8_t tx_buffer[USB_ACM_PCKT_BUFSIZE]; ///< Transmit buffer
 static uint8_t fifo_mem[USB_ACM_FIFO_MEM_SIZE]; ///< Memory assigned to the TX BFifo
 static BFifo fifo;                              ///< TX Blocking FIFO
+static osThreadId_t th;                         ///< ACM thread
+static osEventFlagsId_t flags;                  ///< Event flags
+
+#define USB_ACM_DATA_IN_DONE (0x01)         ///< IN transfer done flag
+#define USB_ACM_COMM_INIT (0x02)            ///< Communication has been initialized
+#define USB_ACM_HOSTBOUND_DATA_AVAIL (0x04) ///< Hostbound data is available
+
+#define USB_ACM_LOOP_TIMEOUT_TICKS (100) ///< Main loop timeout for interrupt status transmission
+
+// -------------------------
+
+static void thread_usb_acm(void *arg) {
+    osEventFlagsWait(flags, USB_ACM_COMM_INIT, 0, osWaitForever); // wait for communication to become initialized
+
+    osEventFlagsSet(flags, USB_ACM_DATA_IN_DONE); // assume we can write to the data endpoint
+
+    while (true) {
+        uint32_t signals = osEventFlagsWait(flags, USB_ACM_HOSTBOUND_DATA_AVAIL, osFlagsWaitAny, USB_ACM_LOOP_TIMEOUT_TICKS);
+
+        if (signals != osErrorTimeout) {                  // check timeout
+            if (signals & USB_ACM_HOSTBOUND_DATA_AVAIL) { // data hostbound available
+                do {
+                    osEventFlagsWait(flags, USB_ACM_DATA_IN_DONE, osFlagsWaitAny, 1000);       // wait for the IN DONE flag
+                    uint32_t readSize = bfifo_read(&fifo, tx_buffer, USB_ACM_PCKT_BUFSIZE); // read from the fifo
+                    if (readSize > 0) {
+                        uint32_t writeSize = usbcore_schedule_transmission(acms.ep_assignments.data_ep, tx_buffer, readSize); // write data acquired from the buffer
+                        bfifo_pop(&fifo, writeSize, 0);                                                                       // pop with no blocking
+                    }
+                } while (bfifo_get_used(&fifo) > 0);
+            }
+        } else { // timeout
+            // send an all-zero interrupt
+            usbcore_schedule_transmission(acms.ep_assignments.control_ep, (const uint8_t *)&(acms.interrupt_data), sizeof(uint16_t));
+        }
+    }
+}
 
 // -------------------------
 
@@ -42,11 +81,20 @@ void usb_acm_init(const Usb_Acm_EpAssignments *as) {
 
     // initialize an all-0 interrupt
     acms.interrupt_data = 0;
-    acms.interrupt_pending = true;
 
     // communication parameters have not been set
     acms.commInit = false;
 
+    // create flags
+    flags = osEventFlagsNew(NULL);
+
+    // create thread
+    osThreadAttr_t attr;
+    memset(&attr, 0, sizeof(osThreadAttr_t));
+    attr.stack_size = 1024;
+    attr.name = "acm";
+    th = osThreadNew(thread_usb_acm, NULL, &attr);
+
     // from now on CDC module is considered initialized
     acms.moduleInit = true;
 }
@@ -61,6 +109,9 @@ static void usb_cdc_review_comm_init() {
 
     // combine the above criteria
     acms.commInit = lcOk && clsOk;
+
+    // signal the processing thread
+    osEventFlagsSet(flags, USB_ACM_COMM_INIT);
 }
 
 int usb_acm_process_and_return(Usb_CallbackEvent *cbevt) {
@@ -108,24 +159,11 @@ int usb_acm_process_and_return(Usb_CallbackEvent *cbevt) {
     }
 
     case USB_CBEVT_IN: {
-        if (cbevt->ep == acms.ep_assignments.control_ep) { // if notification feeding is requested
+        if (cbevt->ep == acms.ep_assignments.data_ep) {
-            if (acms.interrupt_pending) {
+            osEventFlagsSet(flags, USB_ACM_DATA_IN_DONE);
-                usbcore_schedule_transmission(acms.ep_assignments.control_ep, (const uint8_t *)&(acms.interrupt_data), sizeof(uint16_t)); // send ZLP
-                acms.interrupt_pending = false;
-            }
-            ret = 0;
-        } else if (cbevt->ep == acms.ep_assignments.data_ep) { // if data are requested
-            ret = 0;
-
-            // read from the fifo
-            if (acms.commInit) {
-                uint32_t readSize = bfifo_read(&fifo, tx_buffer, USB_ACM_PCKT_BUFSIZE);
-                if (readSize > 0) {
-                    uint32_t writeSize = usbcore_schedule_transmission(acms.ep_assignments.data_ep, tx_buffer, readSize); // write data acquired from the buffer
-                    bfifo_pop(&fifo, writeSize, 0);                                                                       // pop with no blocking
-                }
-            }
         }
+        ret = 0;
+        break;
     }
 
     default:
@@ -138,16 +176,15 @@ int usb_acm_process_and_return(Usb_CallbackEvent *cbevt) {
 void usb_acm_write(const uint8_t *data, uint32_t size) {
     if (acms.moduleInit) {
         bfifo_push_all(&fifo, data, size);
-        usbcore_wake_up_endpoint(acms.ep_assignments.data_ep, USB_IN);
+        osEventFlagsSet(flags, USB_ACM_HOSTBOUND_DATA_AVAIL);
     }
 }
 
-
 /**
  * @fn void usb_acm_read_callback(const uint8_t *data, uint32_t size)
  * Callback function prototype for data reception. This function is
  * expected to be overridden by the application.
- * 
+ *
  * @param data ingress data
  * @param size length of the data
  */

class/acm.h

@@ -82,7 +82,6 @@ typedef struct {
     Usb_Acm_LineCodingStruct line_coding;              ///< Line Coding
     Usb_Acm_ControlLineStateStruct control_line_state; ///< Control Line State
     uint16_t interrupt_data;                           ///< Data sent though the next transfer on the notification element
-    bool interrupt_pending;                            ///< Interrupt data is valid and should be send in the next cycle
     bool moduleInit;                                   ///< CDC module is initialized
     bool commInit;                                     ///< Communication protocol is initialized
 } Usb_AcmState;