Since altera_uart_interrupt() may also be called from
a poll timer in "serving_softirq" context, use
spin_[lock_irqsave|unlock_irqrestore] variants, which
are appropriate for both softirq and hardware interrupt
contexts.
Fixes: 2f8b9c15cd88 ("altera_uart: Add support for polling mode (IRQ-less)")
Signed-off-by: Gabriel Somlo <gsomlo@xxxxxxxxx>
---
I used this driver as a sorce of inspiration for adding IRQ support to
the LiteX LiteUART, and this topic came up during review. So I thought
it might be helpful to fix it here as well!
drivers/tty/serial/altera_uart.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/tty/serial/altera_uart.c b/drivers/tty/serial/altera_uart.c
index 316074bb23e9..9ce3d24af536 100644
--- a/drivers/tty/serial/altera_uart.c
+++ b/drivers/tty/serial/altera_uart.c
@@ -259,16 +259,17 @@ static irqreturn_t altera_uart_interrupt(int irq, void *data)
{
struct uart_port *port = data;
struct altera_uart *pp = container_of(port, struct altera_uart, port);
+ unsigned long flags;
unsigned int isr;
isr = altera_uart_readl(port, ALTERA_UART_STATUS_REG) & pp->imr;
- spin_lock(&port->lock);
+ spin_lock_irqsave(&port->lock, flags);
if (isr & ALTERA_UART_STATUS_RRDY_MSK)
altera_uart_rx_chars(port);
if (isr & ALTERA_UART_STATUS_TRDY_MSK)
altera_uart_tx_chars(port);
- spin_unlock(&port->lock);
+ spin_unlock_irqrestore(&port->lock, flags);
return IRQ_RETVAL(isr);
}
--
2.38.1
