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author | Alan Cox <alan@linux.intel.com> | 2009-11-30 13:17:57 +0000 |
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committer | Greg Kroah-Hartman <gregkh@suse.de> | 2009-12-11 15:18:07 -0800 |
commit | f5c5a36d27ae6d9e03c2f1b7890942bf84e92c5b (patch) | |
tree | 169cdf790a4938c504b0968e83d5d09ad402e554 | |
parent | f176178ba09d27cc33988435e2c9fe078b44998c (diff) | |
download | linux-3.10-f5c5a36d27ae6d9e03c2f1b7890942bf84e92c5b.tar.gz linux-3.10-f5c5a36d27ae6d9e03c2f1b7890942bf84e92c5b.tar.bz2 linux-3.10-f5c5a36d27ae6d9e03c2f1b7890942bf84e92c5b.zip |
tty: moxa: rework the locking a bit
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 <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
-rw-r--r-- | 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 d8bcbed6d28..474d936d3b3 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; |