Add configurable SPI device for Touchscreens

src/lgfx/v1/Touch.hpp

@@ -19,6 +19,7 @@ Original Source:
 
 #include <stdint.h>
 #include <stddef.h>
+#include "platforms/common.hpp"
 
 namespace lgfx
 {
@@ -67,14 +68,27 @@ namespace lgfx
         };
       };
       int16_t pin_cs = -1;
+#if defined (ARDUINO_DEFAULT)
+      HardwareSPI *touch_SPI = nullptr;
+#endif
     };
 
     virtual ~ITouch(void) = default;
 
     config_t config(void) const { return _cfg; }
-    void config(const config_t& config) { _cfg = config; }
-
+    void config(const config_t& config)
+    {
+      _cfg = config;
+#if defined (ARDUINO_DEFAULT)
+      if (_cfg.touch_SPI != nullptr)
+        lgfx::v1::spi::set_SPI(_cfg.touch_SPI);
+#endif
+    }
+#if defined (ARDUINO_DEFAULT)
+    inline bool isSPI(void) const { return _cfg.pin_cs >= 0 || _cfg.touch_SPI != nullptr; }
+#else
     inline bool isSPI(void) const { return _cfg.pin_cs >= 0; }
+#endif
 
     virtual bool init(void) = 0;
     virtual void wakeup(void) = 0;
@@ -85,6 +99,9 @@ namespace lgfx
   protected:
     config_t _cfg;
     bool _inited = false;
+#if defined (ARDUINO_DEFAULT)
+    HardwareSPI *touch_SPI = nullptr;
+#endif
   };
 
 //----------------------------------------------------------------------------

src/lgfx/v1/platforms/arduino_default/common.cpp

@@ -64,18 +64,21 @@ namespace lgfx
 
 //----------------------------------------------------------------------------
 
-  /// unimplemented.
   namespace spi
   {
+    HardwareSPI *SPI_dev = &SPI;
     cpp::result<void, error_t> init(int spi_host, int spi_sclk, int spi_miso, int spi_mosi)  { cpp::result<void, error_t> res = {}; return res; }
+    void set_SPI(HardwareSPI * new_SPI) { SPI_dev = new_SPI; }
     void release(int spi_host) {}
     void beginTransaction(int spi_host, uint32_t freq, int spi_mode) {
       SPISettings setting(freq, MSBFIRST, SPI_MODE0);
-      SPI.beginTransaction(setting);
+      SPI_dev->beginTransaction(setting);
     }
-    void endTransaction(int spi_host) {SPI.endTransaction();}
+    void endTransaction(int spi_host) { SPI_dev->endTransaction();}
     void writeBytes(int spi_host, const uint8_t* data, size_t length) {}
-    void readBytes(int spi_host, uint8_t* data, size_t length) {SPI.transfer(data, length);}  }
+    void readBytes(int spi_host, uint8_t* data, size_t length) {
+      SPI_dev->transfer(data, length);
+      }  }
 
 //----------------------------------------------------------------------------
 

src/lgfx/v1/platforms/common.hpp

@@ -47,6 +47,7 @@ Original Source:
 
 #elif defined (ARDUINO)
 
+#define ARDUINO_DEFAULT
 #include "arduino_default/common.hpp"
 
 #elif __has_include(<SDL2/SDL.h>) || __has_include(<SDL.h>)
@@ -160,6 +161,9 @@ namespace lgfx
   namespace spi
   {
     cpp::result<void, error_t> init(int spi_host, int spi_sclk, int spi_miso, int spi_mosi);
+#if defined (ARDUINO_DEFAULT)
+    void set_SPI(HardwareSPI * new_SPI);
+#endif
     void release(int spi_host);
     void beginTransaction(int spi_host, uint32_t freq, int spi_mode = 0);
     void endTransaction(int spi_host);

src/lgfx/v1/touch/Touch_XPT2046.cpp

@@ -31,8 +31,10 @@ namespace lgfx
     _inited = false;
     if (!isSPI()) return false;
 
-    lgfx::gpio_hi(_cfg.pin_cs);
-    lgfx::pinMode(_cfg.pin_cs, lgfx::pin_mode_t::output);
+    if (_cfg.pin_cs > -1) {
+      lgfx::gpio_hi(_cfg.pin_cs);
+      lgfx::pinMode(_cfg.pin_cs, lgfx::pin_mode_t::output);
+    }
     if (_cfg.spi_host < 0)
     {
       pinMode(_cfg.pin_sclk, lgfx::pin_mode_t::output);
@@ -110,9 +112,11 @@ namespace lgfx
     else
     {
       spi::beginTransaction(_cfg.spi_host, _cfg.freq, 0);
-      lgfx::gpio_lo(_cfg.pin_cs);
+      if (_cfg.pin_cs > -1)
+        lgfx::gpio_lo(_cfg.pin_cs);
       spi::readBytes(_cfg.spi_host, data, 57);
-      lgfx::gpio_hi(_cfg.pin_cs);
+      if (_cfg.pin_cs > -1)
+        lgfx::gpio_hi(_cfg.pin_cs);
       spi::endTransaction(_cfg.spi_host);
     }