HAL for Linux (#13146)

Marlin/src/HAL/HAL_LINUX/hardware/Heater.h

@@ -0,0 +1,47 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (C) 2019 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 <http://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+#include "Gpio.h"
+
+struct LowpassFilter {
+  uint64_t data_delay = 0;
+  uint16_t update(uint16_t value) {
+    data_delay = data_delay - (data_delay >> 6) + value;
+    return (uint16_t)(data_delay >> 6);
+  }
+};
+
+class Heater: public Peripheral {
+public:
+  Heater(pin_t heater, pin_t adc);
+  virtual ~Heater();
+  void interrupt(GpioEvent ev);
+  void update();
+
+  pin_t heater_pin, adc_pin;
+  uint16_t room_temp_raw;
+  uint16_t heater_state;
+  LowpassFilter pwmcap;
+  double heat;
+  uint64_t last;
+};