diff options
Diffstat (limited to 'drivers/serial/8250.c')
| -rw-r--r-- | drivers/serial/8250.c | 20 |
1 files changed, 14 insertions, 6 deletions
diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c index a97f1ae11f7..9ccc563d873 100644 --- a/drivers/serial/8250.c +++ b/drivers/serial/8250.c @@ -1885,7 +1885,7 @@ static int serial8250_startup(struct uart_port *port) * the interrupt is enabled. Delays are necessary to * allow register changes to become visible. */ - spin_lock(&up->port.lock); + spin_lock_irqsave(&up->port.lock, flags); if (up->port.flags & UPF_SHARE_IRQ) disable_irq_nosync(up->port.irq); @@ -1901,22 +1901,30 @@ static int serial8250_startup(struct uart_port *port) if (up->port.flags & UPF_SHARE_IRQ) enable_irq(up->port.irq); - spin_unlock(&up->port.lock); + spin_unlock_irqrestore(&up->port.lock, flags); /* * If the interrupt is not reasserted, setup a timer to * kick the UART on a regular basis. */ if (!(iir1 & UART_IIR_NO_INT) && (iir & UART_IIR_NO_INT)) { + up->bugs |= UART_BUG_THRE; pr_debug("ttyS%d - using backup timer\n", port->line); - up->timer.function = serial8250_backup_timeout; - up->timer.data = (unsigned long)up; - mod_timer(&up->timer, jiffies + - poll_timeout(up->port.timeout) + HZ / 5); } } /* + * The above check will only give an accurate result the first time + * the port is opened so this value needs to be preserved. + */ + if (up->bugs & UART_BUG_THRE) { + up->timer.function = serial8250_backup_timeout; + up->timer.data = (unsigned long)up; + mod_timer(&up->timer, jiffies + + poll_timeout(up->port.timeout) + HZ / 5); + } + + /* * If the "interrupt" for this port doesn't correspond with any * hardware interrupt, we use a timer-based system. The original * driver used to do this with IRQ0. |