Initial commit for dht11-lcd example.

esp/cpp/components/i2c.h

@@ -0,0 +1,92 @@
+/*#############################################################################
+## Author: Shaun Reed                                                        ##
+## Legal: All Content (c) 2025 Shaun Reed, all rights reserved               ##
+##                                                                           ##
+## Contact: shaunrd0@gmail.com  | URL: www.shaunreed.com                     ##
+##############################################################################
+*/
+#ifndef I2C_H
+#define I2C_H
+
+#define I2C_BUS_PORT  0
+
+#include <esp_log.h>
+#include <driver/i2c_master.h>
+
+/**
+ * Encapsulates ESP I2C creation and usage.
+ */
+struct I2C {
+  /**
+   * Construct and initialize an ESP I2C master bus.
+   * An I2C constructor may only be called one time in any application.
+   *
+   * @param sda GPIO pin number for SDA
+   * @param scl GPIO pin number for SCL
+   * @param rst GPIO pin number for RST
+   */
+  I2C(gpio_num_t sda, gpio_num_t scl, int rst = -1) :
+      I2C((i2c_master_bus_config_t) {
+              .i2c_port = I2C_BUS_PORT,
+              .sda_io_num = sda,
+              .scl_io_num = scl,
+              .clk_source = I2C_CLK_SRC_DEFAULT,
+              .glitch_ignore_cnt = 7,
+              .flags {
+                  .enable_internal_pullup = true,
+              },
+          },
+          rst
+      ) { }
+
+  /**
+   * Construct an ESP I2C master bus given a specific ESP I2C configuration.
+   * An I2C constructor may only be called one time in any application.
+   *
+   * @param config ESP I2C master bus configuration.
+   * @param rst GPIO pin number for RST
+   */
+  explicit I2C(i2c_master_bus_config_t config, int rst = -1) :
+      esp_bus_config_(config),
+      rst_num_(rst)
+  {
+    i2c_master_bus_handle_t i2c;
+    ESP_LOGI(TAG, "Initializing new master I2C bus");
+    ESP_ERROR_CHECK(i2c_new_master_bus(&esp_bus_config_, &i2c));
+  }
+
+  ~I2C() = default;
+
+  //
+  // GETTERS
+
+  /**
+   * ESP I2C master bus handle getter.
+   * This will fail if an I2C instance was never constructed.
+   */
+  static i2c_master_bus_handle_t get()
+  {
+    i2c_master_bus_handle_t i2c = nullptr;
+    ESP_ERROR_CHECK(i2c_master_get_bus_handle(0, &i2c));
+    return i2c;
+  }
+
+  //
+  // PUBLIC MEMBERS
+
+  /// ESP I2C master bus configuration used during initialization.
+  i2c_master_bus_config_t esp_bus_config_;
+
+  /// RST GPIO pin number.
+  int rst_num_;
+
+private:
+
+  //
+  // PRIVATE MEMBERS
+
+  /// Tag used for ESP logging.
+  constexpr static const char *TAG = "I2C";
+};
+
+#endif //I2C_H