From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Garzik Subject: Re: [PATCH 1/1] libata-dev: ata_check_atapi_dma() fix for ATA_FLAG_PIO_POLLING LLDDs Date: Mon, 13 Mar 2006 03:09:33 -0500 Message-ID: <441528BD.8070708@pobox.com> References: <441525DB.40905@tw.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail.dvmed.net ([216.237.124.58]:43744 "EHLO mail.dvmed.net") by vger.kernel.org with ESMTP id S932345AbWCMIJg (ORCPT ); Mon, 13 Mar 2006 03:09:36 -0500 In-Reply-To: <441525DB.40905@tw.ibm.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: albertl@mail.com Cc: IDE Linux , Tejun Heo , Doug Maxey Albert Lee wrote: > ata_check_atapi_dma() fix for LLDDs with the ATA_FLAG_PIO_POLLING flag. > > Signed-off-by: Albert Lee > --- > > We don't support polling DMA. > If the LLDD handles only interrupts in the HSM_ST_LAST state > (indicated by the ATA_FLAG_PIO_POLLING flag) and the ATAPI device > generates CDB interrupts, we have to use the polling PIO protocol. > (Otherwise, the CDB interrupts might confuse the LLDD.) > > We just set the protocol to PIO here in ata_check_atapi_dma(). > Later in ata_qc_issue_prot(), the PIO protocol will be set as "polling" > for those LLDDs. > > Patch against the irq-pio branch + > (1) irq-pio minor fixes (respin) + > (2) integrate polling pio with irq-pio (respin) Applied, though I think its an open question what happens with CDB-interrupt ATAPI devices want to do DMA. Perhaps we just get an interrupt event that we clear, then life proceeds as normal. Does anybody actually have such a device anywhere? :) Jeff