Add I2C driver abstraction

boards/main/CMakeLists.txt

@@ -1,4 +1,5 @@
 file(GLOB_RECURSE MAIN_SOURCES "*.cpp")
 
 idf_component_register(SRCS ${MAIN_SOURCES}
-                       INCLUDE_DIRS ".")
+                       INCLUDE_DIRS "."
+                       REQUIRES driver)

boards/main/Kconfig.projbuild

@@ -0,0 +1,13 @@
+menu "Rocket board configuration"
+    orsource "$IDF_PATH/examples/common_components/env_caps/$IDF_TARGET/Kconfig.env_caps"
+
+    config I2C_SDA_GPIO
+        int "I2C SDA GPIO number"
+        range ENV_GPIO_RANGE_MIN ENV_GPIO_OUT_RANGE_MAX
+        default 7
+
+    config I2C_SCL_GPIO
+        int "I2C SCL GPIO number"
+        range ENV_GPIO_RANGE_MIN ENV_GPIO_OUT_RANGE_MAX
+        default 6
+endmenu

boards/main/common.h

@@ -0,0 +1,12 @@
+#pragma once
+
+#include <cstdint>
+
+enum class Result : uint8_t {
+    SUCCESS = 0,
+    FAILURE,
+
+    I2C_INIT_FAILED,
+    I2C_WRITE_FAILED,
+    I2C_READ_FAILED,
+};

boards/main/i2c.cpp

@@ -0,0 +1,98 @@
+#include "i2c.h"
+
+#include <cstring>
+
+#include "driver/i2c.h"
+#include "esp_log.h"
+
+namespace i2c {
+
+constexpr inline const char *TAG = "I2C";
+
+// The project uses only one I2C bus
+constexpr inline i2c_port_t BUS_NUMBER = I2C_NUM_0;
+
+constexpr inline int FREQUENCY = 400000;
+
+constexpr inline uint32_t TIMEOUT = 50;
+
+Result init() {
+    i2c_config_t conf = {
+        .mode = I2C_MODE_MASTER,
+        .sda_io_num = CONFIG_I2C_SDA_GPIO,
+        .scl_io_num = CONFIG_I2C_SCL_GPIO,
+        .sda_pullup_en = true,
+        .scl_pullup_en = true,
+        .master =
+            {
+                .clk_speed = FREQUENCY,
+            },
+        .clk_flags = I2C_SCLK_SRC_FLAG_FOR_NOMAL,
+    };
+
+    if (i2c_param_config(BUS_NUMBER, &conf) != ESP_OK) {
+        ESP_LOGE(TAG, "Config error");
+        return Result::I2C_INIT_FAILED;
+    }
+
+    if (i2c_driver_install(BUS_NUMBER, conf.mode, 0, 0, 0) != ESP_OK) {
+        ESP_LOGE(TAG, "Init error");
+        return Result::I2C_INIT_FAILED;
+    }
+
+    return Result::SUCCESS;
+}
+
+Result read(uint8_t addr, uint8_t reg, uint8_t *buffer, uint16_t size) {
+    if (i2c_master_write_read_device(BUS_NUMBER, addr, &reg, 1, buffer, size,
+                                     TIMEOUT / portTICK_PERIOD_MS) != ESP_OK) {
+        ESP_LOGE(TAG, "Failed to read");
+        return Result::I2C_READ_FAILED;
+    }
+
+    return Result::SUCCESS;
+}
+
+static Result performWriteTransaction(uint8_t addr, uint8_t reg,
+                                      const uint8_t *buffer, uint16_t size,
+                                      i2c_cmd_handle_t command) {
+    if (i2c_master_start(command) != ESP_OK) {
+        return Result::I2C_WRITE_FAILED;
+    }
+    if (i2c_master_write_byte(command, addr << 1U, true) != ESP_OK) {
+        return Result::I2C_WRITE_FAILED;
+    }
+    if (i2c_master_write_byte(command, reg, true) != ESP_OK) {
+        return Result::I2C_WRITE_FAILED;
+    }
+    if (i2c_master_write(command, buffer, size, true) != ESP_OK) {
+        return Result::I2C_WRITE_FAILED;
+    }
+    if (i2c_master_stop(command) != ESP_OK) {
+        return Result::I2C_WRITE_FAILED;
+    }
+    if (i2c_master_cmd_begin(BUS_NUMBER, command, TIMEOUT) != ESP_OK) {
+        return Result::I2C_WRITE_FAILED;
+    }
+    return Result::SUCCESS;
+}
+
+Result write(uint8_t addr, uint8_t reg, const uint8_t *buffer, uint16_t size) {
+    uint8_t command_buffer[I2C_LINK_RECOMMENDED_SIZE(2)] = {0};
+    i2c_cmd_handle_t command = i2c_cmd_link_create_static(
+        command_buffer, I2C_LINK_RECOMMENDED_SIZE(2));
+
+    Result res = performWriteTransaction(addr, reg, buffer, size, command);
+    if (res != Result::SUCCESS) {
+        ESP_LOGE(TAG, "Failed to write");
+        i2c_cmd_link_delete_static(command);
+
+        return res;
+    }
+
+    i2c_cmd_link_delete_static(command);
+
+    return Result::SUCCESS;
+}
+
+}  // namespace i2c

boards/main/i2c.h

@@ -0,0 +1,13 @@
+#pragma once
+
+#include <cstdint>
+
+#include "common.h"
+
+namespace i2c {
+
+Result init();
+Result read(uint8_t addr, uint8_t reg, uint8_t *buffer, uint16_t size);
+Result write(uint8_t addr, uint8_t reg, const uint8_t *buffer, uint16_t size);
+
+}  // namespace i2c

boards/main/main.cpp

@@ -1,11 +1,12 @@
-#include "esp_log.h"
 #include "freertos/FreeRTOS.h"
+#include "i2c.h"
 
 static const char *TAG = "rocket";
 
 extern "C" void app_main(void) {
+    i2c::init();
+
     while (true) {
-        ESP_LOGI(TAG, "Hello World!");
-        vTaskDelay(1000 / portTICK_PERIOD_MS);
+        vTaskDelay(10 / portTICK_PERIOD_MS);
     }
 }