From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753272Ab1JLNDp (ORCPT ); Wed, 12 Oct 2011 09:03:45 -0400 Received: from mail-gx0-f174.google.com ([209.85.161.174]:45958 "EHLO mail-gx0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752859Ab1JLNDm (ORCPT ); Wed, 12 Oct 2011 09:03:42 -0400 Message-ID: <4E95902B.7080204@monstr.eu> Date: Wed, 12 Oct 2011 15:03:39 +0200 From: Michal Simek Reply-To: monstr@monstr.eu User-Agent: Thunderbird 2.0.0.22 (X11/20090625) MIME-Version: 1.0 To: linux-serial@vger.kernel.org CC: Greg Kroah-Hartman , LKML , Peter Korsgaard Subject: Using serial driver 16550A in poll mode without interrupt connected Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, we have internal discussion around serial drivers and their usage without interrupts in polling mode. It is on FPGA with Microblaze/PPC/ARM and it is easy for us to have serial IP without IRQ connected to the interrupt controller. Driver is probed with no IRQ (NO_IRQ = -1 on Microblaze) 83e00000.serial: ttyS0 at MMIO 0x83e01003 (irq = -1) is a 16550A writing any data to ttyS0 return -1. Is there any reason no to use driver in poll mode especially for user applications not for consoles. Is it possible to use serial driver without IRQ - or blocking IRQ, etc.? Currently we care about uart16550 and uarlite. Thanks, Michal -- Michal Simek, Ing. (M.Eng) w: www.monstr.eu p: +42-0-721842854 Maintainer of Linux kernel 2.6 Microblaze Linux - http://www.monstr.eu/fdt/ Microblaze U-BOOT custodian