增加GPIO的访问类

app/src/main/cpp/CMakeLists.txt

@@ -264,6 +264,7 @@ add_library( # Sets the name of the library.
         SHARED
 
         # Provides a relative path to your source file(s).
+        GPIOControl.cpp
         MicroPhoto.cpp
         TerminalDevice.cpp
         PhoneDevice.cpp

app/src/main/cpp/GPIOControl.cpp

@@ -0,0 +1,156 @@
+//
+// Created by Matthew on 2023/12/27.
+//
+
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <fcntl.h>
+#include <sys/mman.h>
+#include <unistd.h>
+
+
+#include "GPIOControl.h"
+
+#define GPIO_DIRECTION_IN              0
+#define GPIO_DIRECTION_OUT             1
+#define GPIO_VALUE_LOW             0
+#define GPIO_VALUE_HIGH            1
+
+#define BUFFER_MAX    3
+#define DIRECTION_MAX 48
+
+int GpioControl::exp(int gpio)
+{
+    char buffer[BUFFER_MAX];
+    int len;
+    int fd;
+
+    fd = open("/sys/class/gpio/export", O_WRONLY);
+    if (fd < 0)
+    {
+        // LOGE("Failed to open export for writing!\n");
+        return(0);
+    }
+
+    len = snprintf(buffer, BUFFER_MAX, "%d", gpio);
+    if (write(fd, buffer, len) < 0)
+    {
+        // LOGE("Fail to export gpio!\n");
+        return 0;
+    }
+
+    close(fd);
+    return 1;
+}
+
+int GpioControl::setDirection(int gpio, int direction)
+{
+    static const char dir_str[]  = "in\0out";
+    char path[DIRECTION_MAX];
+    int fd;
+
+    snprintf(path, DIRECTION_MAX, "/sys/class/gpio/gpio%d/direction", gpio);
+    fd = open(path, O_WRONLY);
+    if (fd < 0)
+    {
+        // LOGE("failed to open gpio direction for writing!\n");
+        return 0;
+    }
+
+    if (write(fd, &dir_str[direction == GPIO_DIRECTION_IN ? 0 : 3], direction == GPIO_DIRECTION_IN ? 2 : 3) < 0)
+    {
+        // LOGE("failed to set direction!\n");
+        return 0;
+    }
+
+    close(fd);
+    return 1;
+}
+int GpioControl::readStatus(int gpio)
+{
+    char path[DIRECTION_MAX];
+    char value_str[3];
+    int fd;
+
+    snprintf(path, DIRECTION_MAX, "/sys/class/gpio/gpio%d/value", gpio);
+    fd = open(path, O_RDONLY);
+    if (fd < 0)
+    {
+        // LOGE("failed to open gpio value for reading!\n");
+        return -1;
+    }
+
+    if (read(fd, value_str, 3) < 0)
+    {
+        // LOGE("failed to read value!\n");
+        return -1;
+    }
+
+    close(fd);
+    return (atoi(value_str));
+}
+
+int GpioControl::writeStatus(int gpio, int value)
+{
+    static const char values_str[] = "01";
+    char path[DIRECTION_MAX];
+    int fd;
+
+    snprintf(path, DIRECTION_MAX, "/sys/class/gpio/gpio%d/value", gpio);
+    fd = open(path, O_WRONLY);
+    if (fd < 0)
+    {
+        // LOGE("failed to open gpio value for writing!\n");
+        return 0;
+    }
+
+    if (write(fd, &values_str[value == GPIO_VALUE_LOW ? 0 : 1], 1) < 0)
+    {
+        // LOGE("failed to write value!\n");
+        return 0;
+    }
+
+    close(fd);
+    return 1;
+}
+
+int GpioControl::unexp(int gpio)
+{
+    char buffer[BUFFER_MAX];
+    int len;
+    int fd;
+
+    fd = open("/sys/class/gpio/unexport", O_WRONLY);
+    if (fd < 0)
+    {
+        // LOGE("Failed to open unexport for writing!\n");
+        return 0;
+    }
+
+    len = snprintf(buffer, BUFFER_MAX, "%d", gpio);
+    if (write(fd, buffer, len) < 0)
+    {
+        // LOGE("Fail to unexport gpio!");
+        return 0;
+    }
+
+    close(fd);
+    return 1;
+}
+
+bool GpioControl::EnableGpio(int gpio, bool en)
+{
+    GpioControl gpioControl;
+    gpioControl.exp(gpio);
+    gpioControl.setDirection(gpio, GPIO_DIRECTION_OUT);
+
+    gpioControl.writeStatus(gpio, en ? GPIO_VALUE_HIGH : GPIO_VALUE_LOW);
+
+    gpioControl.unexp(gpio);
+
+    return true;
+}

app/src/main/cpp/GPIOControl.h

@@ -0,0 +1,22 @@
+//
+// Created by Matthew on 2023/12/27.
+//
+
+#ifndef MICROPHOTO_GPIOCONTROL_H
+#define MICROPHOTO_GPIOCONTROL_H
+
+
+class GpioControl
+{
+public:
+    int exp(int gpio);
+    int setDirection(int gpio, int direction);
+    int readStatus(int gpio);
+    int writeStatus(int gpio, int value);
+    int unexp(int gpio);
+
+    static bool EnableGpio(int gpio, bool en);
+};
+
+
+#endif //MICROPHOTO_GPIOCONTROL_H