From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jiri Slaby Subject: 8250 regression: infinite interrupts Date: Fri, 27 Jan 2012 15:22:30 +0100 Message-ID: <4F22B326.4060605@suse.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-2 Content-Transfer-Encoding: 7bit Return-path: Received: from mail-ww0-f44.google.com ([74.125.82.44]:40792 "EHLO mail-ww0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752510Ab2A0OWh (ORCPT ); Fri, 27 Jan 2012 09:22:37 -0500 Sender: linux-serial-owner@vger.kernel.org List-Id: linux-serial@vger.kernel.org To: philippe.langlais@stericsson.com, Alan Cox , Greg KH , Linux kernel mailing list , linux-serial@vger.kernel.org Hi, the commit below causes infinite interrupts to be generated on some chips. Namely on IBM x3850 M2. commit 235dae5d094c415fcf0fc79fa637f1901bc8afe2 Author: Philippe Langlais Date: Thu Jul 29 17:13:57 2010 +0200 U6715 16550A serial driver support The culprit is the added size_fifo call proper in autoconfig_16550a. It returns 16, but the chip is confused by what the function does at that point. It is yet to be investigated why. Any ideas at this stage why this could be a problem? thanks, -- js suse labs