Want to add a logo to theme customizer

I have added a logo upload in a child theme of twentythirteen. It works great but the only issue i'm having is getting the site title to be replaced by the logo. I have tried several if/else statements and none seem to work.
Is it possible to just change the H1 to show the Site Title unless a logo has been uploaded?

Here is the code.

<a>" title="<?php echo esc_attr( get_bloginfo( 'name', 'display' ) ); ?>" rel="home">
				<h1 </a><a><img src='<?php echo esc_url( get_theme_mod( 'logo_image' ) ); ?>' />  <?php bloginfo( 'name' ); ?> </h1>
				<h2 class="site-description"><?php bloginfo( 'description' ); ?></h2>
			</a>