diff options
Diffstat (limited to 'drivers/tty/serial/meson_uart.c')
| -rw-r--r-- | drivers/tty/serial/meson_uart.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/drivers/tty/serial/meson_uart.c b/drivers/tty/serial/meson_uart.c index efee3935917f..62e6c1af1344 100644 --- a/drivers/tty/serial/meson_uart.c +++ b/drivers/tty/serial/meson_uart.c @@ -253,6 +253,14 @@ static const char *meson_uart_type(struct uart_port *port) return (port->type == PORT_MESON) ? "meson_uart" : NULL; } +/* + * This function is called only from probe() using a temporary io mapping + * in order to perform a reset before setting up the device. Since the + * temporarily mapped region was successfully requested, there can be no + * console on this port at this time. Hence it is not necessary for this + * function to acquire the port->lock. (Since there is no console on this + * port at this time, the port->lock is not initialized yet.) + */ static void meson_uart_reset(struct uart_port *port) { u32 val; @@ -267,9 +275,12 @@ static void meson_uart_reset(struct uart_port *port) static int meson_uart_startup(struct uart_port *port) { + unsigned long flags; u32 val; int ret = 0; + spin_lock_irqsave(&port->lock, flags); + val = readl(port->membase + AML_UART_CONTROL); val |= AML_UART_CLEAR_ERR; writel(val, port->membase + AML_UART_CONTROL); @@ -285,6 +296,8 @@ static int meson_uart_startup(struct uart_port *port) val = (AML_UART_RECV_IRQ(1) | AML_UART_XMIT_IRQ(port->fifosize / 2)); writel(val, port->membase + AML_UART_MISC); + spin_unlock_irqrestore(&port->lock, flags); + ret = request_irq(port->irq, meson_uart_interrupt, 0, port->name, port); |