Show category in custom post type

Hi there,

I′ve downloaded a theme, but i′m used to work with custom post type in wordpress. Normally i can filter quite easily my custom post type on a category, but this time it′s not working and i don′t know why.

Normally i use tax query in my $args array, but it’s not working right know. Do you guys have any suggestions?

<?php
	$args = array(
	'post_type' => 'portfolio',
	'taxonomy' => 'home',
	'numberposts' => 10,
	'orderby' => 'ASC',
	);
	$portfolio_posts = get_posts($args);?>
<?php if($portfolio_posts) { ?>
<div id="homepage-portfolio-wrap">
<?php if($options['home_portfolio_title'] != '') { ?>
<h2><?php echo stripslashes($options['home_portfolio_title']);  ?></h2>
<?php } else { ?>
<h2><?php _e( 'Latest Work' ); ?></h2>
<?php } ?>
    <ul id="homepage-portfolio">
		<?php
        foreach($portfolio_posts as $post) : setup_postdata($post); ?>
        <?php $thumbnail = wp_get_attachment_image_src(get_post_thumbnail_id(), 'portfolio-homepage'); ?>

<li>

Sorry couldn’t post this in advanced wordpress