Signed-off-by: 吴文峰 <kevin@lmve.net>

code/firmware-2.7.15.567b8ea/src/GpioLogic.h

@@ -0,0 +1,160 @@
+#pragma once
+
+#include "configuration.h"
+
+/**This is a set of classes to mediate access to GPIOs in a structured way.  Most usage of GPIOs do not
+    require these classes!  But if your hardware has a GPIO that is 'shared' between multiple devices (i.e. a shared power enable)
+    then using these classes might be able to let you cleanly turn on that enable when either dependent device is needed.
+
+    Note: these classes are intended to be 99% inline for the common case so should have minimal impact on flash or RAM
+   requirements.
+*/
+
+/**
+ * A logical GPIO pin (not necessary raw hardware).
+ */
+class GpioPin
+{
+  public:
+    virtual void set(bool value) = 0;
+};
+
+/**
+ * A physical GPIO hw pin.
+ */
+class GpioHwPin : public GpioPin
+{
+    uint32_t num;
+
+  public:
+    explicit GpioHwPin(uint32_t num) : num(num) {}
+
+    void set(bool value);
+};
+
+class GpioTransformer;
+class GpioNotTransformer;
+class GpioBinaryTransformer;
+
+/**
+ * A virtual GPIO pin.
+ */
+class GpioVirtPin : public GpioPin
+{
+    friend class GpioBinaryTransformer;
+    friend class GpioUnaryTransformer;
+
+  public:
+    enum PinState { On = true, Off = false, Unset = 2 };
+
+    void set(bool value);
+    PinState get() const { return value; }
+
+  private:
+    PinState value = PinState::Unset;
+    GpioTransformer *dependentPin = NULL;
+};
+
+#include <assert.h>
+
+/**
+ * A 'smart' trigger that can depend in a fake GPIO and if that GPIO changes, drive some other downstream GPIO to change.
+ * notably: the set method is not public (because it always is calculated by a subclass)
+ */
+class GpioTransformer
+{
+  public:
+    /**
+     * Update the output pin based on the current state of the input pin.
+     */
+    virtual void update() = 0;
+
+  protected:
+    GpioTransformer(GpioPin *outPin);
+
+    void set(bool value);
+
+  private:
+    GpioPin *outPin;
+};
+
+/**
+ * A transformer that just drives a hw pin based on a virtual pin.
+ */
+class GpioUnaryTransformer : public GpioTransformer
+{
+  public:
+    GpioUnaryTransformer(GpioVirtPin *inPin, GpioPin *outPin);
+
+  protected:
+    friend class GpioVirtPin;
+
+    /**
+     * Update the output pin based on the current state of the input pin.
+     */
+    virtual void update();
+
+    GpioVirtPin *inPin;
+};
+
+/**
+ * A transformer that performs a unary NOT operation from an input.
+ */
+class GpioNotTransformer : public GpioUnaryTransformer
+{
+  public:
+    GpioNotTransformer(GpioVirtPin *inPin, GpioPin *outPin) : GpioUnaryTransformer(inPin, outPin) {}
+
+  protected:
+    friend class GpioVirtPin;
+
+    /**
+     * Update the output pin based on the current state of the input pin.
+     */
+    void update();
+};
+
+/**
+ * A transformer that combines multiple virtual pins to drive an output pin
+ */
+class GpioBinaryTransformer : public GpioTransformer
+{
+
+  public:
+    enum Operation { And, Or, Xor };
+
+    GpioBinaryTransformer(GpioVirtPin *inPin1, GpioVirtPin *inPin2, GpioPin *outPin, Operation operation);
+
+  protected:
+    friend class GpioVirtPin;
+
+    /**
+     * Update the output pin based on the current state of the input pins.
+     */
+    void update();
+
+  private:
+    GpioVirtPin *inPin1;
+    GpioVirtPin *inPin2;
+    Operation operation;
+};
+
+/**
+ * Sometimes a single output GPIO single needs to drive multiple physical GPIOs.  This class provides that.
+ */
+class GpioSplitter : public GpioPin
+{
+
+  public:
+    GpioSplitter(GpioPin *outPin1, GpioPin *outPin2);
+
+    void set(bool value)
+    {
+        outPin1->set(value);
+        outPin2->set(value);
+    }
+
+  private:
+    GpioPin *outPin1;
+    GpioPin *outPin2;
+};