1 files changed, 118 insertions, 0 deletions
diff --git a/Marlin/src/HAL/LINUX/include/serial.h b/Marlin/src/HAL/LINUX/include/serial.h
new file mode 100644
index 0000000..2585be2
--- /dev/null
+++ b/Marlin/src/HAL/LINUX/include/serial.h
@@ -0,0 +1,118 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2020 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+#include "../../../inc/MarlinConfigPre.h"
+#if ENABLED(EMERGENCY_PARSER)
+  #include "../../../feature/e_parser.h"
+#endif
+#include "../../../core/serial_hook.h"
+
+#include <stdarg.h>
+#include <stdio.h>
+
+/**
+ * Generic RingBuffer
+ * T type of the buffer array
+ * S size of the buffer (must be power of 2)
+ */
+template <typename T, uint32_t S> class RingBuffer {
+public:
+  RingBuffer() { index_read = index_write = 0; }
+  uint32_t available() volatile { return index_write - index_read; }
+  uint32_t free() volatile      { return buffer_size - available(); }
+  bool empty() volatile         { return index_read == index_write; }
+  bool full() volatile          { return available() == buffer_size; }
+  void clear() volatile         { index_read = index_write = 0; }
+
+  bool peek(T *value) volatile {
+    if (value == 0 || available() == 0)
+      return false;
+    *value = buffer[mask(index_read)];
+    return true;
+  }
+
+  int read() volatile {
+    if (empty()) return -1;
+    return buffer[mask(index_read++)];
+  }
+
+  bool write(T value) volatile {
+    if (full()) return false;
+    buffer[mask(index_write++)] = value;
+    return true;
+  }
+
+private:
+  uint32_t mask(uint32_t val) volatile {
+    return buffer_mask & val;
+  }
+
+  static const uint32_t buffer_size = S;
+  static const uint32_t buffer_mask = buffer_size - 1;
+  volatile T buffer[buffer_size];
+  volatile uint32_t index_write;
+  volatile uint32_t index_read;
+};
+
+struct HalSerial {
+  HalSerial() { host_connected = true; }
+
+  void begin(int32_t) {}
+  void end()          {}
+
+  int peek() {
+    uint8_t value;
+    return receive_buffer.peek(&value) ? value : -1;
+  }
+
+  int read() { return receive_buffer.read(); }
+
+  size_t write(char c) {
+    if (!host_connected) return 0;
+    while (!transmit_buffer.free());
+    return transmit_buffer.write(c);
+  }
+
+  bool connected() { return host_connected; }
+
+  uint16_t available() {
+    return (uint16_t)receive_buffer.available();
+  }
+
+  void flush() { receive_buffer.clear(); }
+
+  uint8_t availableForWrite() {
+    return transmit_buffer.free() > 255 ? 255 : (uint8_t)transmit_buffer.free();
+  }
+
+  void flushTX() {
+    if (host_connected)
+      while (transmit_buffer.available()) { /* nada */ }
+  }
+
+  volatile RingBuffer<uint8_t, 128> receive_buffer;
+  volatile RingBuffer<uint8_t, 128> transmit_buffer;
+  volatile bool host_connected;
+};
+
+typedef Serial0Type<HalSerial> MSerialT;