From patchwork Sun Jan 3 05:06:14 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Finn Thain X-Patchwork-Id: 7941591 Return-Path: X-Original-To: patchwork-linux-scsi@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 95F6C9F744 for ; Sun, 3 Jan 2016 05:21:03 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id CB4D9200F2 for ; Sun, 3 Jan 2016 05:21:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C96BD20260 for ; Sun, 3 Jan 2016 05:21:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753001AbcACFU5 (ORCPT ); Sun, 3 Jan 2016 00:20:57 -0500 Received: from kvm5.telegraphics.com.au ([98.124.60.144]:49436 "EHLO kvm5.telegraphics.com.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751945AbcACFSb (ORCPT ); Sun, 3 Jan 2016 00:18:31 -0500 Received: by kvm5.telegraphics.com.au (Postfix, from userid 502) id C487922D5D; Sun, 3 Jan 2016 00:18:11 -0500 (EST) Message-Id: <20160103050522.292805572@telegraphics.com.au> User-Agent: quilt/0.50-1 Date: Sun, 03 Jan 2016 16:06:14 +1100 From: Finn Thain To: "James E.J. Bottomley" , "Martin K. Petersen" , Michael Schmitz , , , Cc: Ondrej Zary Subject: [PATCH v4 73/78] ncr5380: Fix pseudo DMA transfers on 53C400 References: <20160103050501.042035135@telegraphics.com.au> Content-Disposition: inline; filename=72-71 Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Ondrej Zary Pseudo-DMA (PDMA) has been broken for ages, resulting in hangs on 53C400-based cards. According to 53C400 datasheet, PDMA transfer length must be a multiple of 128. Check if that's true and use PIO if it's not. This makes PDMA work on 53C400 (Canon FG2-5202). Signed-off-by: Ondrej Zary Signed-off-by: Finn Thain Reviewed-by: Hannes Reinecke --- drivers/scsi/g_NCR5380.c | 4 ++++ 1 file changed, 4 insertions(+) -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Index: linux/drivers/scsi/g_NCR5380.c =================================================================== --- linux.orig/drivers/scsi/g_NCR5380.c 2016-01-03 16:04:38.000000000 +1100 +++ linux/drivers/scsi/g_NCR5380.c 2016-01-03 16:04:50.000000000 +1100 @@ -702,6 +702,10 @@ static int generic_NCR5380_dma_xfer_len( !(cmd->SCp.this_residual % transfersize)) transfersize = 32 * 1024; + /* 53C400 datasheet: non-modulo-128-byte transfers should use PIO */ + if (transfersize % 128) + transfersize = 0; + return transfersize; }