Invalid argument supplied for foreach() in Laravel 5.5 - development

Invalid argument supplied for foreach() in Laravel 5.5

I am trying to retrieve records from my database but I always end up getting an invalid argument error in the @foreach. My syntax looks correct and I cannot find where the problem is. Kindly help out.

role.blade.php

  <div class="box-body">
    <table id="example1" class="table table-bordered table-striped">
      <thead>
      <tr>
        <!-- <th></th> -->
        <th>Name</th>
        <th>Company ID</th>
        <th>Role Type</th>
      </tr>
      </thead>
      <tbody>
      @foreach ($data as $datas)
      <tr>
        <td></td>
        <td></td>
        <td></td>
      </tr>
      @endforeach
      </tbody>
    </table>
  </div>
</div>

controller.php

public function roles(){
        $data = DB::select('select * from roles');
        return view('admin.roles', ['data'=>'$data']);
    }

routes.php

Route::get('/roles', 'mainController@roles');

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