On the blog Ogle Earth, Stefan Geens has posted an article
on the issue of cameras disabling or restricting GPS functions while in China or near its borders. Apparently, some, but not all, camera companies have interpreted Chinese law to mean that they must not allow some of their cameras to record and display GPS information while in China.
It's important to note that Geens is getting his information largely from the (often cryptic) camera instruction manuals and partly from anecdotal experiences recounted on Internet posts. Geens also plainly believes camera companies should not be restricting GPS functioning, but he did not get any on-the-record explanations from them about why they made these decisions.
That said, his initial analysis suggests that beginning probably in 2011 some companies began restricting GPS functioning in China for some of their cameras. This includes some Nikon Coolpix models, but perhaps not the GP-1 accessory for DSLR cameras (its manual evidently does not mention restrictions). Other companies with some restricted cameras include Panasonic, Fujifilm, and Samsung.
Geens did not find any GPS restrictions on any cameras from Canon, Sony, and Olympus, he says.