Backport tx fifo byte ordering fix for ESP32-WROOM-32

ESP32-HUB75-MatrixPanel-I2S-DMA.cpp

@@ -1,6 +1,5 @@
 #include <Arduino.h>
 #include "ESP32-HUB75-MatrixPanel-I2S-DMA.h"
-//#include "xtensa/core-macros.h"
 
 // Credits: Louis Beaudoin <https://github.com/pixelmatix/SmartMatrix/tree/teensylc>
 // and Sprite_TM: 			https://www.esp32.com/viewtopic.php?f=17&t=3188 and https://www.esp32.com/viewtopic.php?f=13&t=3256
@@ -484,10 +483,14 @@ void IRAM_ATTR MatrixPanel_I2S_DMA::updateMatrixDMABuffer(int16_t x_coord, int16
 	 * data.
 	 */
 
+#ifndef ESP32_S2
     // We need to update the correct uint16_t in the rowBitStruct array, that gets sent out in parallel
     // 16 bit parallel mode - Save the calculated value to the bitplane memory in reverse order to account for I2S Tx FIFO mode1 ordering
+	// Irrelevant for ESP32-S2 the way the FIFO ordering works is different - refer to page 679 of S2 technical reference manual
     x_coord & 1U ? --x_coord : ++x_coord;
+#endif 
 
+	
     uint16_t _colorbitclear = BITMASK_RGB1_CLEAR, _colorbitoffset = 0;
 
     if (y_coord >= ROWS_PER_FRAME){    // if we are drawing to the bottom part of the panel
@@ -661,24 +664,46 @@ void MatrixPanel_I2S_DMA::clearFrameBuffer(bool _buff_id){
 	
 
     // let's set LAT/OE control bits for specific pixels in each color_index subrows
+	// Need to consider the original ESP32's (WROOM) DMA TX FIFO reordering of bytes...
     uint8_t coloridx = dma_buff.rowBits[row_idx]->color_depth;
     do {
       --coloridx;
 
-      // switch pointer to a row for a specific color index
+	  // switch pointer to a row for a specific color index
-      row = dma_buff.rowBits[row_idx]->getDataPtr(coloridx, _buff_id);
+	  row = dma_buff.rowBits[row_idx]->getDataPtr(coloridx, _buff_id);
 
-      // drive latch while shifting out last bit of RGB data
+	  #ifdef ESP32_S2
-      row[dma_buff.rowBits[row_idx]->width - 2] |= BIT_LAT;   // -1 pixel to compensate array index starting at 0
+		// -1 works better on ESP32-S2 ? Because bytes get sent out in order...
-      //row[dma_buff.rowBits[row_idx]->width - 1] |= BIT_LAT;   // -1 pixel to compensate array index starting at 0
+		row[dma_buff.rowBits[row_idx]->width - 1] |= BIT_LAT;   // -1 pixel to compensate array index starting at 0					
+	  #else
+		// We need to update the correct uint16_t in the rowBitStruct array, that gets sent out in parallel
+		// 16 bit parallel mode - Save the calculated value to the bitplane memory in reverse order to account for I2S Tx FIFO mode1 ordering
+		// Irrelevant for ESP32-S2 the way the FIFO ordering works is different - refer to page 679 of S2 technical reference manual
+		row[dma_buff.rowBits[row_idx]->width - 2] |= BIT_LAT;   // -2 in the DMA array is actually -1 when it's reordered by TX FIFO				  
+	  #endif
 
       // need to disable OE before/after latch to hide row transition
       // Should be one clock or more before latch, otherwise can get ghosting
       uint8_t _blank = m_cfg.latch_blanking;
       do {
         --_blank;
-        row[0 + _blank] |= BIT_OE;
+        
-        row[dma_buff.rowBits[row_idx]->width - _blank - 3 ] |= BIT_OE;    // (LAT pulse is (width-2) -1 pixel to compensate array index starting at 0
+	  #ifdef ESP32_S2		
+			row[0 + _blank] |= BIT_OE;
+			row[dma_buff.rowBits[row_idx]->width - _blank - 1 ] |= BIT_OE;    // (LAT pulse is (width-2) -1 pixel to compensate array index starting at 0
+ 	  #else
+		  
+			// Original ESP32 WROOM FIFO Ordering Sucks
+			uint8_t _blank_row_tx_fifo_tmp = 0 + _blank;
+			(_blank_row_tx_fifo_tmp & 1U) ? --_blank_row_tx_fifo_tmp : ++_blank_row_tx_fifo_tmp; 
+			row[_blank_row_tx_fifo_tmp] |= BIT_OE;
+			
+			_blank_row_tx_fifo_tmp = dma_buff.rowBits[row_idx]->width - _blank - 1; // (LAT pulse is (width-2) -1 pixel to compensate array index starting at 0
+			(_blank_row_tx_fifo_tmp & 1U) ? --_blank_row_tx_fifo_tmp : ++_blank_row_tx_fifo_tmp; 
+			row[_blank_row_tx_fifo_tmp] |= BIT_OE;
+			
+	  #endif
+
       } while (_blank);
 
     } while(coloridx);
@@ -741,7 +766,17 @@ void MatrixPanel_I2S_DMA::brtCtrlOE(int brt, const bool _buff_id){
       uint8_t _blank = m_cfg.latch_blanking;
       do {
         --_blank;
-        row[0 + _blank] |= BIT_OE;
+
+	  #ifdef ESP32_S2		
+			row[0 + _blank] |= BIT_OE;
+ 	  #else 
+			// Original ESP32 WROOM FIFO Ordering Sucks
+			uint8_t _blank_row_tx_fifo_tmp = 0 + _blank;
+			(_blank_row_tx_fifo_tmp & 1U) ? --_blank_row_tx_fifo_tmp : ++_blank_row_tx_fifo_tmp; 
+			row[_blank_row_tx_fifo_tmp] |= BIT_OE;					
+	  #endif
+
+        //row[0 + _blank] |= BIT_OE;
         // no need, has been done already
         //row[dma_buff.rowBits[row_idx]->width - _blank - 3 ] |= BIT_OE;    // (LAT pulse is (width-2) -1 pixel to compensate array index starting at 0
       } while (_blank);
@@ -860,8 +895,14 @@ void MatrixPanel_I2S_DMA::hlineDMA(int16_t x_coord, int16_t y_coord, int16_t l,
     int16_t _l = l;
     do {                 // iterate pixels in a row
         int16_t _x = x_coord + --_l;
+		
+#ifdef ESP32_S2		
+        // ESP 32 doesn't need byte flipping for TX FIFO.
+        uint16_t &v = p[_x];
+#else
         // Save the calculated value to the bitplane memory in reverse order to account for I2S Tx FIFO mode1 ordering
         uint16_t &v = p[_x & 1U ? --_x : ++_x];
+#endif		
 
         v &= _colorbitclear;      // reset color bits
         v |= RGB_output_bits;    // set new color bits
@@ -896,8 +937,10 @@ void MatrixPanel_I2S_DMA::vlineDMA(int16_t x_coord, int16_t y_coord, int16_t l,
 	blue  = lumConvTab[blue]; 	
 #endif
 
-  // Save the calculated value to the bitplane memory in reverse order to account for I2S Tx FIFO mode1 ordering
+#ifndef ESP32_S2
+  // Save the calculated value to the bitplane memory in reverse order to account for I2S Tx FIFO mode1 ordering 
   x_coord & 1U ? --x_coord : ++x_coord;
+#endif  
 
   uint8_t color_depth_idx = PIXEL_COLOR_DEPTH_BITS;
   do {    // Iterating through color depth bits (8 iterations)

ESP32-HUB75-MatrixPanel-I2S-DMA.h

@@ -1,17 +1,16 @@
 #ifndef _ESP32_RGB_64_32_MATRIX_PANEL_I2S_DMA
 #define _ESP32_RGB_64_32_MATRIX_PANEL_I2S_DMA
 
-/***************************************************************************************/
+/*******************************************************************************************
-/* COMPILE-TIME OPTIONS - Provide as part of PlatformIO project build_flags.           */
+ * COMPILE-TIME OPTIONS - MUST BE PROVIDED as part of PlatformIO project build_flags.      *
-/***************************************************************************************/
+ * Changing the values just here won't work - as defines needs to persist beyond the scope *
+ * of just this file.                                                                      *
+ *******************************************************************************************/
 /* Enable serial debugging of the library, to see how memory is allocated etc. */
 //#define SERIAL_DEBUG 1
 
-
+/* Do NOT build additional methods optimized for fast drawing,
-/*
+ * i.e. Adafruits drawFastHLine, drawFastVLine, etc...                         */
- * Do NOT build additional methods optimized for fast drawing,
- * i.e. Adafruits drawFastHLine, drawFastVLine, etc...
- */
 //#define NO_FAST_FUNCTIONS
 
 /* Use GFX_Root (https://github.com/mrfaptastic/GFX_Root) instead of Adafruit_GFX library.
@@ -21,7 +20,6 @@
  */
 //#define USE_GFX_ROOT 1
 
-
 /* Physical / Chained HUB75(s) RGB pixel WIDTH and HEIGHT. 
  *
  * This library has been tested with a 64x32 and 64x64 RGB panels. 
@@ -87,11 +85,16 @@
 // #define NO_CIE1931
 
 /***************************************************************************************/
-/* Library Includes!                                                                   */
+/* Core ESP32 hardware / idf includes!                                                 */
 #include <vector>
 #include <memory>
 #include "esp_heap_caps.h"
-#include "esp32_i2s_parallel_v2.h"
+
+#ifdef ESP32_S2
+	#include "esp32-s2_i2s_parallel_v1.h"
+#else
+	#include "esp32_i2s_parallel_v2.h"
+#endif
 
 #ifdef USE_GFX_ROOT
 	#include <FastLED.h>    
@@ -101,7 +104,6 @@
 #endif
 
 
-
 /***************************************************************************************/
 /* Definitions below should NOT be ever changed without rewriting library logic         */
 #define ESP32_I2S_DMA_MODE          I2S_PARALLEL_WIDTH_16    // From esp32_i2s_parallel_v2.h = 16 bits in parallel