Commit 43d46ab1 authored by Maciej W. Rozycki's avatar Maciej W. Rozycki Committed by Linus Torvalds

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: default avatarMaciej W. Rozycki <macro@linux-mips.org>
Cc: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 6d83c067
......@@ -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);
}
/*
......
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