From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758116AbZBFHPt (ORCPT ); Fri, 6 Feb 2009 02:15:49 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756557AbZBFHL1 (ORCPT ); Fri, 6 Feb 2009 02:11:27 -0500 Received: from nwd2mail10.analog.com ([137.71.25.55]:13578 "EHLO nwd2mail10.analog.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754221AbZBFHLU (ORCPT ); Fri, 6 Feb 2009 02:11:20 -0500 X-IronPort-AV: E=Sophos;i="4.37,390,1231131600"; d="scan'208";a="82422018" From: Bryan Wu To: dbrownell@users.sourceforge.net, akpm@linux-foundation.org Cc: spi-devel-general@lists.sourceforge.net, linux-kernel@vger.kernel.org, Mike Frysinger , Bryan Wu Subject: [PATCH 13/20] Blackfin SPI Driver: add timeout while waiting for SPIF in dma irq handler Date: Fri, 6 Feb 2009 15:13:01 +0800 Message-Id: <1233904388-5765-14-git-send-email-cooloney@kernel.org> X-Mailer: git-send-email 1.5.6.3 In-Reply-To: <1233904388-5765-1-git-send-email-cooloney@kernel.org> References: <1233904388-5765-1-git-send-email-cooloney@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Mike Frysinger The "while" endless loop will cause the system hang if hardware error, so we add timeout control to make the system alive. Signed-off-by: Mike Frysinger Signed-off-by: Bryan Wu --- drivers/spi/spi_bfin5xx.c | 12 +++++++++++- 1 files changed, 11 insertions(+), 1 deletions(-) diff --git a/drivers/spi/spi_bfin5xx.c b/drivers/spi/spi_bfin5xx.c index 83398b3..748e98f 100644 --- a/drivers/spi/spi_bfin5xx.c +++ b/drivers/spi/spi_bfin5xx.c @@ -557,6 +557,7 @@ static irqreturn_t dma_irq_handler(int irq, void *dev_id) struct driver_data *drv_data = dev_id; struct chip_data *chip = drv_data->cur_chip; struct spi_message *msg = drv_data->cur_msg; + unsigned long timeout; unsigned short dmastat = get_dma_curr_irqstat(drv_data->dma_channel); u16 spistat = read_STAT(drv_data); @@ -582,8 +583,17 @@ static irqreturn_t dma_irq_handler(int irq, void *dev_id) cpu_relax(); } + dev_dbg(&drv_data->pdev->dev, + "in dma_irq_handler dmastat:0x%x spistat:0x%x\n", + dmastat, read_STAT(drv_data)); + + timeout = jiffies + HZ; while (!(read_STAT(drv_data) & SPIF)) - cpu_relax(); + if (!time_before(jiffies, timeout)) { + dev_warn(&drv_data->pdev->dev, "timeout waiting for SPIF"); + break; + } else + cpu_relax(); if ((dmastat & DMA_ERR) && (spistat & RBSY)) { msg->state = ERROR_STATE; -- 1.5.6.3