From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752063AbbLZKor (ORCPT ); Sat, 26 Dec 2015 05:44:47 -0500 Received: from mail-cys01nam02on0074.outbound.protection.outlook.com ([104.47.37.74]:31744 "EHLO NAM02-CY1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751194AbbLZKnZ (ORCPT ); Sat, 26 Dec 2015 05:43:25 -0500 Authentication-Results: spf=pass (sender IP is 149.199.60.100) smtp.mailfrom=xilinx.com; ettus.com; dkim=none (message not signed) header.d=none;ettus.com; dmarc=bestguesspass action=none header.from=xilinx.com; From: Soren Brinkmann To: Greg Kroah-Hartman , Jiri Slaby CC: Michal Simek , , , , "Peter Hurley" , Moritz Fischer , Soren Brinkmann Subject: [PATCH LINUX v5 7/8] tty: xuartps: Acquire port lock for shutdown Date: Sat, 26 Dec 2015 02:43:55 -0800 Message-ID: <1451126636-13699-8-git-send-email-soren.brinkmann@xilinx.com> X-Mailer: git-send-email 2.6.3.3.g9bb996a In-Reply-To: <1451126636-13699-1-git-send-email-soren.brinkmann@xilinx.com> References: <1451126636-13699-1-git-send-email-soren.brinkmann@xilinx.com> X-RCIS-Action: ALLOW X-TM-AS-Product-Ver: IMSS-7.1.0.1224-8.0.0.1202-22024.006 X-TM-AS-User-Approved-Sender: Yes;Yes X-EOPAttributedMessage: 0 X-Forefront-Antispam-Report: CIP:149.199.60.100;CTRY:US;IPV:NLI;EFV:NLI;SFV:NSPM;SFS:(10009020)(6009001)(2980300002)(438002)(189002)(199003)(19580395003)(77096005)(106466001)(50466002)(87936001)(33646002)(36386004)(76506005)(575784001)(586003)(57986006)(5001770100001)(4001430100002)(86362001)(19580405001)(5003940100001)(2950100001)(1220700001)(92566002)(81156007)(107886002)(5001960100002)(1096002)(47776003)(11100500001)(5008740100001)(36756003)(63266004)(50986999)(6806005)(50226001)(229853001)(76176999)(48376002)(189998001)(107986001)(5001870100001)(217873001);DIR:OUT;SFP:1101;SCL:1;SRVR:BL2NAM02HT176;H:xsj-pvapsmtpgw02;FPR:;SPF:Pass;PTR:xapps1.xilinx.com,unknown-60-100.xilinx.com;MX:1;A:1;LANG:en; MIME-Version: 1.0 Content-Type: text/plain X-Exchange-Antispam-Report-Test: UriScan:;BCL:0;PCL:0;RULEID:(8251501002);SRVR:BL2NAM02HT176;UriScan:(192813158149592); X-Microsoft-Antispam-PRVS: <3a6c09c4536a49f5b7d50a03033e36c0@BL2NAM02HT176.eop-nam02.prod.protection.outlook.com> X-Exchange-Antispam-Report-CFA-Test: BCL:0;PCL:0;RULEID:(601004)(2401047)(520078)(5005006)(8121501046)(10201501046)(3002001);SRVR:BL2NAM02HT176;BCL:0;PCL:0;RULEID:;SRVR:BL2NAM02HT176; X-Forefront-PRVS: 0802ADD973 X-OriginatorOrg: xilinx.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 26 Dec 2015 10:43:21.7988 (UTC) X-MS-Exchange-CrossTenant-Id: 657af505-d5df-48d0-8300-c31994686c5c X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=657af505-d5df-48d0-8300-c31994686c5c;Ip=[149.199.60.100];Helo=[xsj-pvapsmtpgw02] X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: BL2NAM02HT176 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Shutting down the UART port can happen while console operations are in progress. Holding the port lock serializes these operations and avoids the UART HW to be disabled in the middle of console prints. Signed-off-by: Soren Brinkmann Reviewed-by: Peter Hurley --- drivers/tty/serial/xilinx_uartps.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c index ab3995d00973..f3ac69387b0a 100644 --- a/drivers/tty/serial/xilinx_uartps.c +++ b/drivers/tty/serial/xilinx_uartps.c @@ -826,6 +826,9 @@ static int cdns_uart_startup(struct uart_port *port) static void cdns_uart_shutdown(struct uart_port *port) { int status; + unsigned long flags; + + spin_lock_irqsave(&port->lock, flags); /* Disable interrupts */ status = readl(port->membase + CDNS_UART_IMR_OFFSET); @@ -835,6 +838,9 @@ static void cdns_uart_shutdown(struct uart_port *port) /* Disable the TX and RX */ writel(CDNS_UART_CR_TX_DIS | CDNS_UART_CR_RX_DIS, port->membase + CDNS_UART_CR_OFFSET); + + spin_unlock_irqrestore(&port->lock, flags); + free_irq(port->irq, port); } -- 2.6.3.3.g9bb996a