Revert "A fix for the SerialUSB buffer overflow bug."

This reverts commit ee2d18e.

Author: GabrielNotman

cores/arduino/USB/USBCore.cpp

@@ -120,32 +120,12 @@ uint32_t USBD_Send(uint32_t ep, const void* d, uint32_t len)
 	int r = len;
 	const uint8_t* data = (const uint8_t*)d;
 
-  if (!_usbConfiguration)
-  {
-  	TRACE_CORE(printf("pb conf\n\r");)
+    if (!_usbConfiguration)
+    {
+    	TRACE_CORE(printf("pb conf\n\r");)
 		return -1;
-  }
-
-  size_t i = 0;
-  // Ensure the chunk size is aligned 4
-  size_t chunkSize = UDD_IN_CACHE_SIZE -(UDD_IN_CACHE_SIZE % 4);
-
-  // Send the full chunks
-  for (i = 0; i < (len / chunkSize); i++)
-  {
-    UDD_Send(ep, data + (i*chunkSize), chunkSize);
-
-    /* Clear the transfer complete flag  */
-    udd_clear_IN_transf_cplt(ep);
-    /* Set the bank as ready */
-    udd_IN_transfer_allowed(ep);
-
-    /* Wait for transfer to complete */
-    while (!udd_is_IN_transf_cplt(ep));  // need fire exit.
-  }
-
-  // Send the remainder
-  UDD_Send(ep, data + (i * chunkSize), len % chunkSize);
+    }
+	UDD_Send(ep, data, len);
 
 	/* Clear the transfer complete flag  */
 	udd_clear_IN_transf_cplt(ep);

cores/arduino/USB/samd21_device.c

@@ -34,8 +34,8 @@ extern "C"{
 //#define TRACE_DEVICE(x)	x
 #define TRACE_DEVICE(x)
 
-__attribute__((__aligned__(4))) /*__attribute__((__section__(".bss_hram0")))*/ uint8_t udd_ep_out_cache_buffer[4][UDD_OUT_CACHE_SIZE];
-__attribute__((__aligned__(4))) /*__attribute__((__section__(".bss_hram0")))*/ uint8_t udd_ep_in_cache_buffer[4][UDD_IN_CACHE_SIZE];
+__attribute__((__aligned__(4))) /*__attribute__((__section__(".bss_hram0")))*/ uint8_t udd_ep_out_cache_buffer[4][64];
+__attribute__((__aligned__(4))) /*__attribute__((__section__(".bss_hram0")))*/ uint8_t udd_ep_in_cache_buffer[4][128];
 
 /**
  * USB SRAM data containing pipe descriptor table

cores/arduino/USB/samd21_device.h

@@ -26,9 +26,6 @@ extern "C" {
 #define EP0				0
 #define EPX_SIZE		64// 64 for Full Speed, EPT size max is 1024
 
-#define UDD_OUT_CACHE_SIZE 64
-#define UDD_IN_CACHE_SIZE 128
-
 // Force device low speed mode
 #define udd_force_low_speed()               USB->DEVICE.CTRLB.reg &= ~USB_DEVICE_CTRLB_SPDCONF_Msk; USB->DEVICE.CTRLB.reg |= USB_DEVICE_CTRLB_SPDCONF_1_Val
 // Force full speed mode