From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759919AbXKHCPb (ORCPT ); Wed, 7 Nov 2007 21:15:31 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755639AbXKHCPW (ORCPT ); Wed, 7 Nov 2007 21:15:22 -0500 Received: from pip15.gyao.ne.jp ([61.122.117.253]:57550 "EHLO mx.gate01.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753241AbXKHCPV (ORCPT ); Wed, 7 Nov 2007 21:15:21 -0500 Date: Thu, 8 Nov 2007 11:14:56 +0900 From: Paul Mundt To: Jeff Garzik Cc: Alan Cox , Andrew Morton , linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org, linuxsh-dev@lists.sourceforge.net Subject: [PATCH 1/2 take #2] libata: Support PIO polling-only hosts. Message-ID: <20071108021456.GA30648@linux-sh.org> Mail-Followup-To: Paul Mundt , Jeff Garzik , Alan Cox , Andrew Morton , linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org, linuxsh-dev@lists.sourceforge.net MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.13 (2006-08-11) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org By default ata_host_activate() expects a valid IRQ in order to successfully register the host. This patch enables a special case for registering polling-only hosts that either don't have IRQs or have buggy IRQ generation (either in terms of handling or sensing), which otherwise work fine. Hosts that want to use polling mode can simply set ATA_FLAG_PIO_POLLING and pass in an invalid IRQ. Signed-off-by: Paul Mundt --- drivers/ata/libata-core.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c index ec3ce12..89fd0e9 100644 --- a/drivers/ata/libata-core.c +++ b/drivers/ata/libata-core.c @@ -7178,6 +7178,10 @@ int ata_host_register(struct ata_host *host, struct scsi_host_template *sht) * request IRQ and register it. This helper takes necessasry * arguments and performs the three steps in one go. * + * An invalid IRQ skips the IRQ registration and expects the host to + * have set polling mode on the port. In this case, @irq_handler + * should be NULL. + * * LOCKING: * Inherited from calling layer (may sleep). * @@ -7194,6 +7198,12 @@ int ata_host_activate(struct ata_host *host, int irq, if (rc) return rc; + /* Special case for polling mode */ + if (!irq) { + WARN_ON(irq_handler); + return ata_host_register(host, sht); + } + rc = devm_request_irq(host->dev, irq, irq_handler, irq_flags, dev_driver_string(host->dev), host); if (rc)