Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934743AbZLKXcm (ORCPT ); Fri, 11 Dec 2009 18:32:42 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S934477AbZLKXcc (ORCPT ); Fri, 11 Dec 2009 18:32:32 -0500 Received: from kroah.org ([198.145.64.141]:50451 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933911AbZLKX3b (ORCPT ); Fri, 11 Dec 2009 18:29:31 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Alan Cox , Greg Kroah-Hartman Subject: [PATCH 48/58] tty: moxa: rework the locking a bit Date: Fri, 11 Dec 2009 15:28:32 -0800 Message-Id: <1260574122-10676-48-git-send-email-gregkh@suse.de> X-Mailer: git-send-email 1.6.5.3 In-Reply-To: <20091211232805.GA10652@kroah.com> References: <20091211232805.GA10652@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2724 Lines: 86 From: Alan Cox Introduce a lock for moxafunc() to protect the cases where were get collisions between two function requests at the same time. Signed-off-by: Alan Cox Signed-off-by: Greg Kroah-Hartman --- drivers/char/moxa.c | 27 ++++++++++++++++++++++----- 1 files changed, 22 insertions(+), 5 deletions(-) diff --git a/drivers/char/moxa.c b/drivers/char/moxa.c index d8bcbed..474d936 100644 --- a/drivers/char/moxa.c +++ b/drivers/char/moxa.c @@ -248,9 +248,25 @@ static void moxa_wait_finish(void __iomem *ofsAddr) static void moxafunc(void __iomem *ofsAddr, u16 cmd, u16 arg) { + unsigned long flags; + spin_lock_irqsave(&moxafunc_lock, flags); writew(arg, ofsAddr + FuncArg); writew(cmd, ofsAddr + FuncCode); moxa_wait_finish(ofsAddr); + spin_unlock_irqrestore(&moxafunc_lock, flags); +} + +static int moxafuncret(void __iomem *ofsAddr, u16 cmd, u16 arg) +{ + unsigned long flags; + u16 ret; + spin_lock_irqsave(&moxafunc_lock, flags); + writew(arg, ofsAddr + FuncArg); + writew(cmd, ofsAddr + FuncCode); + moxa_wait_finish(ofsAddr); + ret = readw(ofsAddr + FuncArg); + spin_unlock_irqrestore(&moxafunc_lock, flags); + return ret; } static void moxa_low_water_check(void __iomem *ofsAddr) @@ -417,6 +433,7 @@ static const struct tty_port_operations moxa_port_ops = { static struct tty_driver *moxaDriver; static DEFINE_TIMER(moxaTimer, moxa_poll, 0, 0); static DEFINE_SPINLOCK(moxa_lock); +static DEFINE_SPINLOCK(moxafunc_lock); /* * HW init @@ -1823,10 +1840,12 @@ static int MoxaPortSetTermio(struct moxa_port *port, struct ktermios *termio, baud = MoxaPortSetBaud(port, baud); if (termio->c_iflag & (IXON | IXOFF | IXANY)) { + spin_lock_irq(&moxafunc_lock); writeb(termio->c_cc[VSTART], ofsAddr + FuncArg); writeb(termio->c_cc[VSTOP], ofsAddr + FuncArg1); writeb(FC_SetXonXoff, ofsAddr + FuncCode); moxa_wait_finish(ofsAddr); + spin_unlock_irqrestore(&moxafunc_lock); } return baud; @@ -1879,12 +1898,10 @@ static int MoxaPortLineStatus(struct moxa_port *port) int val; ofsAddr = port->tableAddr; - if (MOXA_IS_320(port->board)) { - moxafunc(ofsAddr, FC_LineStatus, 0); - val = readw(ofsAddr + FuncArg); - } else { + if (MOXA_IS_320(port->board)) + val = moxafuncret(ofsAddr, FC_LineStatus, 0); + else val = readw(ofsAddr + FlagStat) >> 4; - } val &= 0x0B; if (val & 8) val |= 4; -- 1.6.5.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/