Hi,
You can't do both and still have the two site indexed. I think your best bet would be to follow advice for webmasters and use hidden meta tags as follows;
On the www site have tags such as;
<link rel="alternate" media="only screen and (max-width: 640px)" href="http://m.example.com/page-1" >
and on the mobile page, have an equivalent tag on the equivalent page:
<link rel="canonical" href="http://www.example.com/page-1" >
Or you can send similar signals with sitemaps (click
here)
If you want to leverage the link weight pointing from the m site to the www as well, then I think the best way would be to just link though from the mobile site.
Cheers,
Paz.