From patchwork Thu Nov 19 20:02:19 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Soren Brinkmann X-Patchwork-Id: 7661021 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 67C88BF90C for ; Thu, 19 Nov 2015 20:03:46 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 8AB1F20459 for ; Thu, 19 Nov 2015 20:03:45 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id A17DC20458 for ; Thu, 19 Nov 2015 20:03:44 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZzVOs-00030I-L7; Thu, 19 Nov 2015 20:01:46 +0000 Received: from mail-bl2nam02on0073.outbound.protection.outlook.com ([104.47.38.73] helo=NAM02-BL2-obe.outbound.protection.outlook.com) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZzVOc-0002nj-6F for linux-arm-kernel@lists.infradead.org; Thu, 19 Nov 2015 20:01:31 +0000 Received: from BL2NAM02FT031.eop-nam02.prod.protection.outlook.com (10.152.76.59) by BL2NAM02HT058.eop-nam02.prod.protection.outlook.com (10.152.76.113) with Microsoft SMTP Server (TLS) id 15.1.331.11; Thu, 19 Nov 2015 20:01:08 +0000 Authentication-Results: spf=pass (sender IP is 149.199.60.83) smtp.mailfrom=xilinx.com; vger.kernel.org; dkim=none (message not signed) header.d=none;vger.kernel.org; dmarc=bestguesspass action=none header.from=xilinx.com; Received-SPF: Pass (protection.outlook.com: domain of xilinx.com designates 149.199.60.83 as permitted sender) receiver=protection.outlook.com; client-ip=149.199.60.83; helo=xsj-pvapsmtpgw01; Received: from xsj-pvapsmtpgw01 (149.199.60.83) by BL2NAM02FT031.mail.protection.outlook.com (10.152.77.173) with Microsoft SMTP Server (TLS) id 15.1.331.11 via Frontend Transport; Thu, 19 Nov 2015 20:01:08 +0000 Received: from unknown-38-66.xilinx.com ([149.199.38.66] helo=xsj-pvapsmtp01) by xsj-pvapsmtpgw01 with esmtp (Exim 4.63) (envelope-from ) id 1ZzVOF-0002xZ-Dx; Thu, 19 Nov 2015 12:01:07 -0800 Received: from [127.0.0.1] (helo=localhost) by xsj-pvapsmtp01 with smtp (Exim 4.63) (envelope-from ) id 1ZzVOF-0003id-7d; Thu, 19 Nov 2015 12:01:07 -0800 Received: from xsj-pvapsmtp01 (xsj-smtp.xilinx.com [149.199.38.66]) by xsj-smtp-dlp1.xlnx.xilinx.com (8.13.8/8.13.1) with ESMTP id tAJK0xYF016943; Thu, 19 Nov 2015 12:00:59 -0800 Received: from [172.19.74.49] (helo=localhost) by xsj-pvapsmtp01 with esmtp (Exim 4.63) (envelope-from ) id 1ZzVO7-0003es-7t; Thu, 19 Nov 2015 12:00:59 -0800 From: Soren Brinkmann To: Greg Kroah-Hartman , Jiri Slaby Subject: [PATH RESEND v2 05/10] tty: xuartps: Improve startup function Date: Thu, 19 Nov 2015 12:02:19 -0800 Message-ID: <1447963344-16266-6-git-send-email-soren.brinkmann@xilinx.com> X-Mailer: git-send-email 2.6.3.3.g9bb996a In-Reply-To: <1447963344-16266-1-git-send-email-soren.brinkmann@xilinx.com> References: <1447963344-16266-1-git-send-email-soren.brinkmann@xilinx.com> X-RCIS-Action: ALLOW X-TM-AS-Product-Ver: IMSS-7.1.0.1224-8.0.0.1202-21950.006 X-TM-AS-User-Approved-Sender: Yes;Yes X-EOPAttributedMessage: 0 X-Forefront-Antispam-Report: CIP:149.199.60.83; CTRY:US; IPV:NLI; EFV:NLI; SFV:NSPM; SFS:(10009020)(6009001)(2980300002)(438002)(199003)(189002)(11100500001)(5007970100001)(33646002)(229853001)(5008740100001)(586003)(6806005)(5003940100001)(92566002)(2950100001)(50986999)(77096005)(63266004)(106466001)(76176999)(86362001)(76506005)(57986006)(575784001)(50466002)(50226001)(48376002)(36756003)(19580405001)(19580395003)(87936001)(189998001)(5001960100002)(5001770100001)(107886002)(5001920100001)(81156007)(4001430100002)(47776003)(36386004)(107986001)(217873001); DIR:OUT; SFP:1101; SCL:1; SRVR:BL2NAM02HT058; H:xsj-pvapsmtpgw01; FPR:; SPF:Pass; PTR:unknown-60-83.xilinx.com; A:1; MX:1; LANG:en; MIME-Version: 1.0 X-Microsoft-Antispam: UriScan:; BCL:0; PCL:0; RULEID:(8251501001); SRVR:BL2NAM02HT058; X-Microsoft-Antispam-PRVS: <07e96e1794594a4dad7ae04c36a49958@BL2NAM02HT058.eop-nam02.prod.protection.outlook.com> X-Exchange-Antispam-Report-Test: UriScan:(192813158149592); X-Exchange-Antispam-Report-CFA-Test: BCL:0; PCL:0; RULEID:(601004)(2401047)(520078)(8121501046)(5005006)(3002001)(10201501046); SRVR:BL2NAM02HT058; BCL:0; PCL:0; RULEID:; SRVR:BL2NAM02HT058; X-Forefront-PRVS: 07658B8EA3 X-OriginatorOrg: xilinx.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 19 Nov 2015 20:01:08.0971 (UTC) X-MS-Exchange-CrossTenant-Id: 657af505-d5df-48d0-8300-c31994686c5c X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=657af505-d5df-48d0-8300-c31994686c5c; Ip=[149.199.60.83]; Helo=[xsj-pvapsmtpgw01] X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: BL2NAM02HT058 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20151119_120130_376093_E14458F8 X-CRM114-Status: GOOD ( 14.05 ) X-Spam-Score: -1.9 (-) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-arm-kernel@lists.infradead.org, Soren Brinkmann , Michal Simek , linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.8 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable 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 The startup function is supposed to initialize the UART for receiving. Hence, don't enable the TX part. Also, protect HW accesses with the port lock. Signed-off-by: Soren Brinkmann --- drivers/tty/serial/xilinx_uartps.c | 20 ++++++++++++-------- 1 file changed, 12 insertions(+), 8 deletions(-) diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c index b7fc30639292..167e0f4bcf7a 100644 --- a/drivers/tty/serial/xilinx_uartps.c +++ b/drivers/tty/serial/xilinx_uartps.c @@ -755,6 +755,7 @@ static void cdns_uart_set_termios(struct uart_port *port, */ static int cdns_uart_startup(struct uart_port *port) { + unsigned long flags; unsigned int retval = 0, status = 0; retval = request_irq(port->irq, cdns_uart_isr, 0, CDNS_UART_NAME, @@ -762,6 +763,8 @@ static int cdns_uart_startup(struct uart_port *port) if (retval) return retval; + spin_lock_irqsave(&port->lock, flags); + /* Disable the TX and RX */ writel(CDNS_UART_CR_TX_DIS | CDNS_UART_CR_RX_DIS, port->membase + CDNS_UART_CR_OFFSET); @@ -772,15 +775,14 @@ static int cdns_uart_startup(struct uart_port *port) writel(CDNS_UART_CR_TXRST | CDNS_UART_CR_RXRST, port->membase + CDNS_UART_CR_OFFSET); - status = readl(port->membase + CDNS_UART_CR_OFFSET); - - /* Clear the RX disable and TX disable bits and then set the TX enable - * bit and RX enable bit to enable the transmitter and receiver. + /* + * Clear the RX disable bit and then set the RX enable bit to enable + * the receiver. */ - writel((status & ~(CDNS_UART_CR_TX_DIS | CDNS_UART_CR_RX_DIS)) - | (CDNS_UART_CR_TX_EN | CDNS_UART_CR_RX_EN | - CDNS_UART_CR_STOPBRK), - port->membase + CDNS_UART_CR_OFFSET); + status = readl(port->membase + CDNS_UART_CR_OFFSET); + status &= CDNS_UART_CR_RX_DIS; + status |= CDNS_UART_CR_RX_EN; + writel(status, port->membase + CDNS_UART_CR_OFFSET); /* Set the Mode Register with normal mode,8 data bits,1 stop bit, * no parity. @@ -811,6 +813,8 @@ static int cdns_uart_startup(struct uart_port *port) CDNS_UART_IXR_RXTRIG | CDNS_UART_IXR_TOUT, port->membase + CDNS_UART_IER_OFFSET); + spin_unlock_irqrestore(&port->lock, flags); + return retval; }