Featured image link to page

I’m trying to have each pages featured image be on the homepage as a link to that respective page (sorta like ecommerce-show a product, click the image, go into the product page). So far I have this code, but feel I am missing something simple. Does anyone have an idea of what to do?

<ul class="main-thumbs">
	<?php
		if ( have_posts() ) {
		     while ( have_posts() ) {
		          the_post();
			      <a href="<?php echo get_permalink(); ?>">
					<?php the_post_thumbnail(); ?>
			      </a>
		     }
		}
	?>
</ul>