Add gpio class

server/gpio/gpio.cpp

@@ -0,0 +1,176 @@
+#include "gpio.hpp"
+#include "spdlog/spdlog.h"
+#include <errno.h>
+#if __aarch64__
+#else
+struct gpiod_chip *gpiod_chip_open(const char *path){return NULL;}
+struct gpiod_line_settings *gpiod_line_settings_new(void){}
+int gpiod_line_settings_set_direction(struct gpiod_line_settings *settings,
+  enum gpiod_line_direction direction){return 0;}
+int gpiod_line_settings_set_output_value(struct gpiod_line_settings *settings,
+    enum gpiod_line_value value){return 0;}
+struct gpiod_line_config *gpiod_line_config_new(void){return NULL;}
+int gpiod_line_config_add_line_settings(struct gpiod_line_config *config,
+  const unsigned int *offsets,
+  size_t num_offsets,
+  struct gpiod_line_settings *settings){return 0;}
+struct gpiod_request_config *gpiod_request_config_new(void){}
+void gpiod_request_config_set_consumer(struct gpiod_request_config *config,
+  const char *consumer){}
+struct gpiod_line_request *
+  gpiod_chip_request_lines(struct gpiod_chip *chip,
+         struct gpiod_request_config *req_cfg,
+         struct gpiod_line_config *line_cfg){return NULL;}
+int gpiod_line_request_set_value(struct gpiod_line_request *request,
+            unsigned int offset,
+            enum gpiod_line_value value){}
+enum gpiod_line_value
+gpiod_line_request_get_value(struct gpiod_line_request *request,
+                             unsigned int offset) {}
+void gpiod_request_config_free(struct gpiod_request_config *config){}
+void gpiod_line_config_free(struct gpiod_line_config *config){}
+void gpiod_line_settings_free(struct gpiod_line_settings *settings){}
+void gpiod_chip_close(struct gpiod_chip *chip){}
+#endif
+
+GPIO::GPIO(Direction dir, uint8_t gpio, bool state, QObject* parent)
+    : QObject(parent), m_offset(gpio)
+{
+    if (dir == Direction::Output)
+    {
+        m_request = request_output_line("/dev/gpiochip0", gpio, (enum gpiod_line_value)state, "Consumer");
+        if (!m_request) {
+            SPDLOG_ERROR("failed to request line: {}",
+                strerror(errno));
+        }
+        return;
+    }
+    if (dir == Direction::Input)
+    {
+        m_request = request_input_line("/dev/gpiochip0", gpio, "get-line-value");
+        if (!m_request) {
+            fprintf(stderr, "failed to request line: %s\n",
+                    strerror(errno));
+        }
+    }
+}
+
+void GPIO::set_value(bool value)
+{
+    gpiod_line_request_set_value(m_request, m_offset, (enum gpiod_line_value)value);
+}
+
+bool GPIO::value()
+{
+    return (bool)gpiod_line_request_get_value(m_request, m_offset);
+}
+
+struct gpiod_line_request *
+GPIO::request_output_line(const char *chip_path, unsigned int offset,
+                    enum gpiod_line_value value, const char *consumer)
+{
+    struct gpiod_request_config *req_cfg = NULL;
+    struct gpiod_line_request *request = NULL;
+    struct gpiod_line_settings *settings;
+    struct gpiod_line_config *line_cfg;
+    struct gpiod_chip *chip;
+    int ret;
+
+    chip = gpiod_chip_open(chip_path);
+    if (!chip)
+        return NULL;
+
+    settings = gpiod_line_settings_new();
+    if (!settings)
+        goto close_chip;
+
+    gpiod_line_settings_set_direction(settings,
+                                      GPIOD_LINE_DIRECTION_OUTPUT);
+    gpiod_line_settings_set_output_value(settings, value);
+
+    line_cfg = gpiod_line_config_new();
+    if (!line_cfg)
+        goto free_settings;
+
+    ret = gpiod_line_config_add_line_settings(line_cfg, &offset, 1,
+                                              settings);
+    if (ret)
+        goto free_line_config;
+
+    if (consumer) {
+        req_cfg = gpiod_request_config_new();
+        if (!req_cfg)
+            goto free_line_config;
+
+        gpiod_request_config_set_consumer(req_cfg, consumer);
+    }
+
+    request = gpiod_chip_request_lines(chip, req_cfg, line_cfg);
+
+    gpiod_request_config_free(req_cfg);
+
+free_line_config:
+    gpiod_line_config_free(line_cfg);
+
+free_settings:
+    gpiod_line_settings_free(settings);
+
+close_chip:
+    gpiod_chip_close(chip);
+
+    return request;
+}
+
+struct gpiod_line_request *GPIO::request_input_line(const char *chip_path,
+                                                     unsigned int offset,
+                                                     const char *consumer)
+{
+    struct gpiod_request_config *req_cfg = NULL;
+    struct gpiod_line_request *request = NULL;
+    struct gpiod_line_settings *settings;
+    struct gpiod_line_config *line_cfg;
+    struct gpiod_chip *chip;
+    int ret;
+
+    chip = gpiod_chip_open(chip_path);
+    if (!chip)
+        return NULL;
+
+    settings = gpiod_line_settings_new();
+    if (!settings)
+        goto close_chip;
+
+    gpiod_line_settings_set_direction(settings, GPIOD_LINE_DIRECTION_INPUT);
+
+    line_cfg = gpiod_line_config_new();
+    if (!line_cfg)
+        goto free_settings;
+
+    ret = gpiod_line_config_add_line_settings(line_cfg, &offset, 1,
+                                              settings);
+    if (ret)
+        goto free_line_config;
+
+    if (consumer) {
+        req_cfg = gpiod_request_config_new();
+        if (!req_cfg)
+            goto free_line_config;
+
+        gpiod_request_config_set_consumer(req_cfg, consumer);
+    }
+
+    request = gpiod_chip_request_lines(chip, req_cfg, line_cfg);
+
+    gpiod_request_config_free(req_cfg);
+
+free_line_config:
+    gpiod_line_config_free(line_cfg);
+
+free_settings:
+    gpiod_line_settings_free(settings);
+
+close_chip:
+    gpiod_chip_close(chip);
+
+    return request;
+}

server/gpio/gpio.hpp

@@ -0,0 +1,55 @@
+#ifndef GPIO_HPP
+#define GPIO_HPP
+
+#include <QObject>
+#ifdef __aarch64__
+#include <gpiod.h>
+#else
+struct gpiod_line_request{};
+struct gpiod_request_config{};
+struct gpiod_line_settings{};
+struct gpiod_line_config{};
+struct gpiod_chip{};
+enum gpiod_line_value {
+	GPIOD_LINE_VALUE_ERROR = -1,
+	/**< Returned to indicate an error when reading the value. */
+	GPIOD_LINE_VALUE_INACTIVE = 0,
+	/**< Line is logically inactive. */
+	GPIOD_LINE_VALUE_ACTIVE = 1,
+	/**< Line is logically active. */
+};
+enum gpiod_line_direction {
+	GPIOD_LINE_DIRECTION_AS_IS = 1,
+	/**< Request the line(s), but don't change direction. */
+	GPIOD_LINE_DIRECTION_INPUT,
+	/**< Direction is input - for reading the value of an externally driven
+	 *   GPIO line. */
+	GPIOD_LINE_DIRECTION_OUTPUT,
+	/**< Direction is output - for driving the GPIO line. */
+};
+#endif
+
+class GPIO : public QObject {
+    Q_OBJECT
+  public:
+    enum Direction {
+        Input,
+        Output
+    };
+    explicit GPIO(Direction dir, uint8_t gpio, bool state = false, QObject* parent = nullptr);
+    void set_value(bool val);
+    bool value();
+
+  private:
+    struct gpiod_line_request *
+    request_output_line(const char *chip_path, unsigned int offset,
+                        enum gpiod_line_value value, const char *consumer);
+    struct gpiod_line_request *request_input_line(const char *chip_path,
+                                                        unsigned int offset,
+                                                        const char *consumer);
+
+    struct gpiod_line_request *m_request;
+    unsigned int m_offset;
+};
+
+#endif // GPIO_HPP