South Australian MP Bernard Finnigan is to face trial on one of two child pornography charges laid against him.

The 41-year-old independent upper house MP was charged with an aggravated count of obtaining child pornography at his home in the Adelaide suburb of Sefton Park on December 24, 2010.

He also faced a charge of taking a step towards obtaining access to child pornography on April 4, 2011.

The MP applied to the District Court for a permanent stay of his pending trial, which Judge Steven Millsteed on Wednesday allowed in relation to the second count.

No date has been set for the trial on the first charge.