diff options
| author | Maciej W. Rozycki <macro@linux-mips.org> | 2008-02-07 00:15:11 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2008-02-07 08:42:24 -0800 |
| commit | 43d46ab1cdeb12b8d072cfdf84956073a1fa8866 (patch) | |
| tree | 00e55a9babe058feef7065621f12c63dd493ff07 | |
| parent | 6d83c067ebd11d375b34c53192c10826947e8568 (diff) | |
| download | op-kernel-dev-43d46ab1cdeb12b8d072cfdf84956073a1fa8866.zip op-kernel-dev-43d46ab1cdeb12b8d072cfdf84956073a1fa8866.tar.gz | |
dz: fix locking issues
The ->start_tx(), ->stop_tx() and ->stop_rx() backends are called with the
port's lock already taken. Remove locking from within them and wrap around
calls as necessary.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | drivers/serial/dz.c | 23 |
1 files changed, 12 insertions, 11 deletions
diff --git a/drivers/serial/dz.c b/drivers/serial/dz.c index c2f8677..656c342 100644 --- a/drivers/serial/dz.c +++ b/drivers/serial/dz.c @@ -108,37 +108,28 @@ static void dz_stop_tx(struct uart_port *uport) { struct dz_port *dport = (struct dz_port *)uport; unsigned short tmp, mask = 1 << dport->port.line; - unsigned long flags; - spin_lock_irqsave(&dport->port.lock, flags); tmp = dz_in(dport, DZ_TCR); /* read the TX flag */ tmp &= ~mask; /* clear the TX flag */ dz_out(dport, DZ_TCR, tmp); - spin_unlock_irqrestore(&dport->port.lock, flags); } static void dz_start_tx(struct uart_port *uport) { struct dz_port *dport = (struct dz_port *)uport; unsigned short tmp, mask = 1 << dport->port.line; - unsigned long flags; - spin_lock_irqsave(&dport->port.lock, flags); tmp = dz_in(dport, DZ_TCR); /* read the TX flag */ tmp |= mask; /* set the TX flag */ dz_out(dport, DZ_TCR, tmp); - spin_unlock_irqrestore(&dport->port.lock, flags); } static void dz_stop_rx(struct uart_port *uport) { struct dz_port *dport = (struct dz_port *)uport; - unsigned long flags; - spin_lock_irqsave(&dport->port.lock, flags); dport->cflag &= ~DZ_CREAD; dz_out(dport, DZ_LPR, dport->cflag | dport->port.line); - spin_unlock_irqrestore(&dport->port.lock, flags); } static void dz_enable_ms(struct uart_port *port) @@ -268,7 +259,9 @@ static inline void dz_transmit_chars(struct dz_port *dport_in) } /* If nothing to do or stopped or hardware stopped. */ if (uart_circ_empty(xmit) || uart_tx_stopped(&dport->port)) { + spin_lock(&dport->port.lock); dz_stop_tx(&dport->port); + spin_unlock(&dport->port.lock); return; } @@ -285,8 +278,11 @@ static inline void dz_transmit_chars(struct dz_port *dport_in) uart_write_wakeup(&dport->port); /* Are we are done. */ - if (uart_circ_empty(xmit)) + if (uart_circ_empty(xmit)) { + spin_lock(&dport->port.lock); dz_stop_tx(&dport->port); + spin_unlock(&dport->port.lock); + } } /* @@ -417,7 +413,12 @@ static int dz_startup(struct uart_port *uport) */ static void dz_shutdown(struct uart_port *uport) { - dz_stop_tx(uport); + struct dz_port *dport = (struct dz_port *)uport; + unsigned long flags; + + spin_lock_irqsave(&dport->port.lock, flags); + dz_stop_tx(&dport->port); + spin_unlock_irqrestore(&dport->port.lock, flags); } /* |
