Read epin maxpacket to determine the max size of USBD_CDC_TransmitPacket() in CDC_continue_transmit()

Author: catbraincell

libraries/USBDevice/inc/cdc_queue.h

@@ -54,7 +54,6 @@ extern "C" {
 #define CDC_QUEUE_MAX_PACKET_SIZE USB_FS_MAX_PACKET_SIZE
 #endif
 
-#define CDC_TRANSMIT_MAX_BUFFER_SIZE    65472       //STM32 USB OTG DIEPTSIZ PKTCNT maximum 0x3ff
 #define CDC_RECEIVE_MAX_BUFFER_SIZE     CDC_QUEUE_MAX_PACKET_SIZE
 
 #ifndef CDC_TRANSMIT_QUEUE_BUFFER_PACKET_NUMBER
@@ -84,7 +83,7 @@ void CDC_TransmitQueue_Init(CDC_TransmitQueue_TypeDef *queue);
 int CDC_TransmitQueue_WriteSize(CDC_TransmitQueue_TypeDef *queue);
 int CDC_TransmitQueue_ReadSize(CDC_TransmitQueue_TypeDef *queue);
 void CDC_TransmitQueue_Enqueue(CDC_TransmitQueue_TypeDef *queue, const uint8_t *buffer, uint32_t size);
-uint8_t *CDC_TransmitQueue_ReadBlock(CDC_TransmitQueue_TypeDef *queue, uint32_t *size);
+uint8_t *CDC_TransmitQueue_ReadBlock(CDC_TransmitQueue_TypeDef *queue, uint32_t *size, uint32_t maxsize);
 void CDC_TransmitQueue_CommitRead(CDC_TransmitQueue_TypeDef *queue);
 
 void CDC_ReceiveQueue_Init(CDC_ReceiveQueue_TypeDef *queue);

libraries/USBDevice/inc/usbd_cdc.h

@@ -145,11 +145,13 @@ uint8_t USBD_CDC_RegisterInterface(USBD_HandleTypeDef *pdev,
                                    USBD_CDC_ItfTypeDef *fops);
 
 #ifdef USE_USBD_COMPOSITE
+uint32_t USBD_CDC_GetTxMaxSize(USBD_HandleTypeDef *pdev, uint8_t ClassId);
 uint8_t USBD_CDC_SetTxBuffer(USBD_HandleTypeDef *pdev, uint8_t *pbuff,
                              uint32_t length, uint8_t ClassId);
 uint8_t USBD_CDC_TransmitPacket(USBD_HandleTypeDef *pdev, uint8_t ClassId);
 uint8_t USBD_CDC_ClearBuffer(USBD_HandleTypeDef *pdev, uint8_t ClassId);
 #else
+uint32_t USBD_CDC_GetTxMaxSize(USBD_HandleTypeDef *pdev);
 uint8_t USBD_CDC_SetTxBuffer(USBD_HandleTypeDef *pdev, uint8_t *pbuff,
                              uint32_t length);
 uint8_t USBD_CDC_TransmitPacket(USBD_HandleTypeDef *pdev);

libraries/USBDevice/src/cdc/cdc_queue.c

@@ -77,15 +77,15 @@ void CDC_TransmitQueue_Enqueue(CDC_TransmitQueue_TypeDef *queue,
 
 // Read flat block from queue biggest as possible, but max QUEUE_MAX_PACKET_SIZE
 uint8_t *CDC_TransmitQueue_ReadBlock(CDC_TransmitQueue_TypeDef *queue,
-                                     uint32_t *size)
+                                     uint32_t *size,
+                                     uint32_t maxsize)
 {
   if (queue->write >= queue->read) {
     *size = queue->write - queue->read;
   } else {
     *size = CDC_TRANSMIT_QUEUE_BUFFER_SIZE - queue->read;
   }
-  if(*size > CDC_TRANSMIT_MAX_BUFFER_SIZE)
-    *size = CDC_TRANSMIT_MAX_BUFFER_SIZE;
+  if(*size > maxsize) *size = maxsize;
 
   queue->reserved = *size;
   return &queue->buffer[queue->read];

libraries/USBDevice/src/cdc/usbd_cdc.c

@@ -79,6 +79,7 @@
 /** @defgroup USBD_CDC_Private_Defines
   * @{
   */
+#define USB_MAX_PKTCNT  1023
 /**
   * @}
   */
@@ -896,6 +897,25 @@ uint8_t USBD_CDC_RegisterInterface(USBD_HandleTypeDef *pdev,
   return (uint8_t)USBD_OK;
 }
 
+/**
+  * @brief  USBD_CDC_GetTxMaxSize
+  * @param  pdev: device instance
+  * @param  ClassId: The Class ID
+  * @retval status
+  */
+#ifdef USE_USBD_COMPOSITE
+uint8_t USBD_CDC_GetTxMaxSize(USBD_HandleTypeDef *pdev, uint8_t ClassId)
+{
+  /* Get the Endpoints addresses allocated for this class instance */
+  CDCInEpAdd  = USBD_CoreGetEPAdd(pdev, USBD_EP_IN, USBD_EP_TYPE_BULK, ClassId);
+#else
+uint8_t USBD_CDC_GetTxMaxSize(USBD_HandleTypeDef *pdev)
+{
+#endif /* USE_USBD_COMPOSITE */
+
+  return pdev->ep_in[CDCInEpAdd & 0xFU].maxpacket * USB_MAX_PKTCNT;
+}
+ 
 /**
   * @brief  USBD_CDC_SetTxBuffer
   * @param  pdev: device instance

libraries/USBDevice/src/cdc/usbd_cdc_if.c

@@ -25,13 +25,6 @@
 #include "usbd_cdc_if.h"
 #include "bootloader.h"
 
-#ifdef USE_USB_HS
-  #define CDC_MAX_PACKET_SIZE USB_OTG_HS_MAX_PACKET_SIZE
-#elif defined(USB_OTG_FS) || defined(USB_OTG_FS_MAX_PACKET_SIZE)
-  #define CDC_MAX_PACKET_SIZE USB_OTG_FS_MAX_PACKET_SIZE
-#else /* USB */
-  #define CDC_MAX_PACKET_SIZE USB_MAX_EP0_SIZE
-#endif
 
 /*
  * The value USB_CDC_TRANSMIT_TIMEOUT is defined in terms of HAL_GetTick() units.
@@ -342,7 +335,8 @@ void CDC_continue_transmit(void)
    * is higher than that of the main thread. So this method is thread safe.
    */
   if (hcdc->TxState == 0U) {
-    buffer = CDC_TransmitQueue_ReadBlock(&TransmitQueue, &size);
+    uint32_t maxsize = USBD_CDC_GetTxMaxSize(&hUSBD_Device_CDC);
+    buffer = CDC_TransmitQueue_ReadBlock(&TransmitQueue, &size, maxsize);
     if (size > 0) {
       transmitStart = HAL_GetTick();
       USBD_CDC_SetTxBuffer(&hUSBD_Device_CDC, buffer, size);