fix SAMD21 definition and turn on DMA for CPX (gizmo is big) - tested with ST7789 gizmo

Adafruit_SPITFT.cpp

@@ -50,7 +50,7 @@
 #define digitalPinToPort(P) (&(PORT_IOBUS->Group[g_APinDescription[P].ulPort]))
 #endif // end PORT_IOBUS
 
-#if defined(USE_SPI_DMA) && (defined(__SAMD51__) || defined(__SAMD21__))
+#if defined(USE_SPI_DMA) && (defined(__SAMD51__) || defined(ARDUINO_SAMD_ZERO))
 // #pragma message ("GFX DMA IS ENABLED. HIGHLY EXPERIMENTAL.")
  #include <Adafruit_ZeroDMA.h>
  #include "wiring_private.h"  // pinPeripheral() function
@@ -648,7 +648,7 @@ void Adafruit_SPITFT::initSPI(uint32_t freq, uint8_t spiMode) {
         delay(200);
     }
 
-#if defined(USE_SPI_DMA) && (defined(__SAMD51__) || defined(__SAMD21__))
+#if defined(USE_SPI_DMA) && (defined(__SAMD51__) || defined(ARDUINO_SAMD_ZERO))
     if(((connection == TFT_HARD_SPI) || (connection == TFT_PARALLEL)) &&
        (dma.allocate() == DMA_STATUS_OK)) { // Allocate channel
         // The DMA library needs to alloc at least one valid descriptor,
@@ -1003,7 +1003,7 @@ void Adafruit_SPITFT::writePixels(uint16_t *colors, uint32_t len,
     }
 
     return;
-#elif defined(USE_SPI_DMA) && (defined(__SAMD51__) || defined(__SAMD21__))
+#elif defined(USE_SPI_DMA) && (defined(__SAMD51__) || defined(ARDUINO_SAMD_ZERO))
     if((connection == TFT_HARD_SPI) || (connection == TFT_PARALLEL)) {
         int     maxSpan     = maxFillLen / 2; // One scanline max
         uint8_t pixelBufIdx = 0;              // Active pixel buffer number
@@ -1076,14 +1076,14 @@ void Adafruit_SPITFT::writePixels(uint16_t *colors, uint32_t len,
         lastFillLen   = 0;
         if(block) {
             while(dma_busy);    // Wait for last line to complete
- #if defined(__SAMD51__) || defined(_SAMD21_)
+ #if defined(__SAMD51__) || defined(ARDUINO_SAMD_ZERO)
             if(connection == TFT_HARD_SPI) {
                 // See SAMD51/21 note in writeColor()
                 hwspi._spi->setDataMode(hwspi._mode);
             } else {
                 pinPeripheral(tft8._wr, PIO_OUTPUT); // Switch WR back to GPIO
             }
- #endif // end __SAMD51__ || _SAMD21_
+ #endif // end __SAMD51__ || ARDUINO_SAMD_ZERO
         }
         return;
     }
@@ -1103,16 +1103,16 @@ void Adafruit_SPITFT::writePixels(uint16_t *colors, uint32_t len,
             was used (as is the default case).
 */
 void Adafruit_SPITFT::dmaWait(void) {
-#if defined(USE_SPI_DMA) && (defined(__SAMD51__) || defined(__SAMD21__))
+#if defined(USE_SPI_DMA) && (defined(__SAMD51__) || defined(ARDUINO_SAMD_ZERO))
     while(dma_busy);
- #if defined(__SAMD51__) || defined(_SAMD21_)
+ #if defined(__SAMD51__) || defined(ARDUINO_SAMD_ZERO)
     if(connection == TFT_HARD_SPI) {
         // See SAMD51/21 note in writeColor()
         hwspi._spi->setDataMode(hwspi._mode);
     } else {
         pinPeripheral(tft8._wr, PIO_OUTPUT); // Switch WR back to GPIO
     }
- #endif // end __SAMD51__ || _SAMD21_
+ #endif // end __SAMD51__ || ARDUINO_SAMD_ZERO
 #endif
 }
 
@@ -1175,7 +1175,7 @@ void Adafruit_SPITFT::writeColor(uint16_t color, uint32_t len) {
       return;
     }
 #else  // !ESP32
- #if defined(USE_SPI_DMA) && (defined(__SAMD51__) || defined(__SAMD21__))
+ #if defined(USE_SPI_DMA) && (defined(__SAMD51__) || defined(ARDUINO_SAMD_ZERO))
     if(((connection == TFT_HARD_SPI) || (connection == TFT_PARALLEL)) &&
        (len >= 16)) { // Don't bother with DMA on short pixel runs
         int i, d, numDescriptors;
@@ -1252,7 +1252,7 @@ void Adafruit_SPITFT::writeColor(uint16_t color, uint32_t len) {
         // turns out to be MUCH slower on many graphics operations (as when
         // drawing lines, pixel-by-pixel), perhaps because it's a volatile
         // type and doesn't cache. Working on this.
-  #if defined(__SAMD51__) || defined(_SAMD21_)
+  #if defined(__SAMD51__) || defined(ARDUINO_SAMD_ZERO)
         if(connection == TFT_HARD_SPI) {
             // SAMD51: SPI DMA seems to leave the SPI peripheral in a freaky
             // state on completion. Workaround is to explicitly set it back...

Adafruit_SPITFT.h

@@ -73,7 +73,7 @@ typedef volatile  ADAGFX_PORT_t* PORTreg_t; ///< PORT register type
 
 #if defined(ADAFRUIT_PYPORTAL) || defined(ADAFRUIT_PYBADGE_M4_EXPRESS) || \
     defined(ADAFRUIT_PYGAMER_M4_EXPRESS)|| defined(ADAFRUIT_MONSTER_M4SK_EXPRESS) || \
-    defined(NRF52_SERIES)
+    defined(NRF52_SERIES) || defined(ADAFRUIT_CIRCUITPLAYGROUND_M0)
  #define USE_SPI_DMA                 ///< Auto DMA
 #else
  //#define USE_SPI_DMA               ///< If set, use DMA if available
@@ -84,7 +84,7 @@ typedef volatile  ADAGFX_PORT_t* PORTreg_t; ///< PORT register type
 // 4 bytes/pixel on display major axis + 8 bytes/pixel on minor axis,
 // e.g. 320x240 pixels = 320 * 4 + 240 * 8 = 3,200 bytes.
 
-#if defined(USE_SPI_DMA) && (defined(__SAMD51__) || defined(__SAMD21__))
+#if defined(USE_SPI_DMA) && (defined(__SAMD51__) || defined(ARDUINO_SAMD_ZERO))
  #include <Adafruit_ZeroDMA.h>
 #endif
 
@@ -477,7 +477,7 @@ class Adafruit_SPITFT : public Adafruit_GFX {
 #if defined(__cplusplus) && (__cplusplus >= 201100)
     };                             ///< Only one interface is active
 #endif
-#if defined(USE_SPI_DMA) && (defined(__SAMD51__) || defined(__SAMD21__)) // Used by hardware SPI and tft8
+#if defined(USE_SPI_DMA) && (defined(__SAMD51__) || defined(ARDUINO_SAMD_ZERO)) // Used by hardware SPI and tft8
     Adafruit_ZeroDMA dma;                  ///< DMA instance
     DmacDescriptor  *dptr          = NULL; ///< 1st descriptor
     DmacDescriptor  *descriptor    = NULL; ///< Allocated descriptor list