From 315ec77812802e263891d25181bfdb09dd57ba56 Mon Sep 17 00:00:00 2001
From: Pimpest <82343504+Pimpest@users.noreply.github.com>
Date: Mon, 5 May 2025 15:04:42 +0200
Subject: [PATCH] Added simple node fore i2c comunication

---
 mg_bt/CMakeLists.txt        |  3 +++
 mg_bt/i2cmodule/i2cnode.cpp | 35 +++++++++++++++++++++++++++++++++++
 mg_bt/package.xml           |  1 +
 mg_msgs/CMakeLists.txt      |  1 +
 mg_msgs/srv/I2c.srv         |  4 ++++
 5 files changed, 44 insertions(+)
 create mode 100644 mg_bt/i2cmodule/i2cnode.cpp
 create mode 100644 mg_msgs/srv/I2c.srv

diff --git a/mg_bt/CMakeLists.txt b/mg_bt/CMakeLists.txt
index 837a473..a684a21 100644
--- a/mg_bt/CMakeLists.txt
+++ b/mg_bt/CMakeLists.txt
@@ -37,6 +37,7 @@ set(SOURCES
 
 
 add_executable(mg_bt_executor ${SOURCES})
+add_executable(mg_i2cnode i2cmodule/i2cnode.cpp)
 
 target_include_directories(
   mg_bt_executor
@@ -46,9 +47,11 @@ target_include_directories(
 )
 
 ament_target_dependencies(mg_bt_executor ${PACKAGE_DEPS})
+ament_target_dependencies(mg_i2cnode rclcpp mg_msgs)
 
 install( TARGETS
   mg_bt_executor
+  mg_i2cnode
   DESTINATION lib/${PROJECT_NAME}
 )
 
diff --git a/mg_bt/i2cmodule/i2cnode.cpp b/mg_bt/i2cmodule/i2cnode.cpp
new file mode 100644
index 0000000..398cf2a
--- /dev/null
+++ b/mg_bt/i2cmodule/i2cnode.cpp
@@ -0,0 +1,35 @@
+#include "rclcpp/rclcpp.hpp"
+#include "mg_msgs/srv/i2c.hpp"
+
+#include <fcntl.h>
+#include <linux/i2c-dev.h>
+#include <sys/ioctl.h>
+#include <i2c/smbus.h>
+
+class MgI2c : public rclcpp::Node {
+    using I2cSrv = mg_msgs::srv::I2c;
+
+  public:
+    MgI2c(const std::string& name) : rclcpp::Node(name), i2c_fd_(open("/dev/i2c-1", O_RDWR)) { // NOLINT
+        auto cb
+          = [this](I2cSrv::Request::ConstSharedPtr req, I2cSrv::Response::SharedPtr resp) { send_req(req, resp); };
+        i2c_srv_ = create_service<I2cSrv>("/i2c", cb);
+    }
+
+    void send_req(I2cSrv::Request::ConstSharedPtr req, I2cSrv::Response::SharedPtr resp) const {
+        ioctl(i2c_fd_, I2C_SLAVE, req->addr); // NOLINT
+        int ch = i2c_smbus_read_byte_data(i2c_fd_, req->data);
+        resp->resp.push_back(ch);
+        RCLCPP_INFO(get_logger(), "Recieved %d", resp->resp.front());
+    }
+
+  private:
+    rclcpp::Service<mg_msgs::srv::I2c>::SharedPtr i2c_srv_;
+    int                                           i2c_fd_;
+};
+
+int main(int argc, const char* const* argv) {
+    rclcpp::init(argc, argv);
+
+    return 0;
+}
\ No newline at end of file
diff --git a/mg_bt/package.xml b/mg_bt/package.xml
index 0c34014..c3161ab 100644
--- a/mg_bt/package.xml
+++ b/mg_bt/package.xml
@@ -14,6 +14,7 @@
   <depend>behaviortree_ros2</depend>
   <depend>btcpp_ros2_interfaces</depend>
   <depend>mg_msgs</depend>
+  <depend>libi2c-dev</depend>
 
   <test_depend>ament_lint_auto</test_depend>
   <test_depend>ament_lint_common</test_depend>
diff --git a/mg_msgs/CMakeLists.txt b/mg_msgs/CMakeLists.txt
index d062b16..baf9be1 100644
--- a/mg_msgs/CMakeLists.txt
+++ b/mg_msgs/CMakeLists.txt
@@ -19,6 +19,7 @@ rosidl_generate_interfaces(${PROJECT_NAME}
   "action/Rotate.action"
   "srv/CalcPath.srv"
   "srv/SendDouble.srv"
+  "srv/I2c.srv"
 )
 
 ament_package()
\ No newline at end of file
diff --git a/mg_msgs/srv/I2c.srv b/mg_msgs/srv/I2c.srv
new file mode 100644
index 0000000..7ef0a5b
--- /dev/null
+++ b/mg_msgs/srv/I2c.srv
@@ -0,0 +1,4 @@
+uint8 addr
+uint8 data
+---
+uint8[] resp
\ No newline at end of file