Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755256AbcJ3WkX (ORCPT ); Sun, 30 Oct 2016 18:40:23 -0400 Received: from ns.gsystem.sk ([62.176.172.50]:57887 "EHLO gsystem.sk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752546AbcJ3WkV (ORCPT ); Sun, 30 Oct 2016 18:40:21 -0400 From: Ondrej Zary To: Christoph Hellwig Cc: Finn Thain , linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 3/3] NCR5380: Check for chip presence in NCR5380_init() Date: Sun, 30 Oct 2016 23:40:03 +0100 Message-Id: <1477867203-7480-3-git-send-email-linux@rainbow-software.org> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1477867203-7480-1-git-send-email-linux@rainbow-software.org> References: <1477867203-7480-1-git-send-email-linux@rainbow-software.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 847 Lines: 28 Read back MODE_REG after writing it in NCR5380_init() to check if the chip is really there. This prevents hang when incorrect I/O address was specified by user. Signed-off-by: Ondrej Zary --- drivers/scsi/NCR5380.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/scsi/NCR5380.c b/drivers/scsi/NCR5380.c index 01c0027..ce3156d 100644 --- a/drivers/scsi/NCR5380.c +++ b/drivers/scsi/NCR5380.c @@ -495,6 +495,11 @@ static int NCR5380_init(struct Scsi_Host *instance, int flags) NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); NCR5380_write(MODE_REG, MR_BASE); + /* check if the chip is really there */ + if (NCR5380_read(MODE_REG) != MR_BASE) { + NCR5380_exit(instance); + return -ENODEV; + } NCR5380_write(TARGET_COMMAND_REG, 0); NCR5380_write(SELECT_ENABLE_REG, 0); -- Ondrej Zary