tty: xuartps: Acquire port lock for shutdown

Shutting down the UART port can happen while console operations are in
progress. Holding the port lock serializes these operations and avoids
the UART HW to be disabled in the middle of console prints.

Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Soren Brinkmann 2015-12-26 02:43:55 -08:00 committed by Greg Kroah-Hartman
parent 4c0b92ed9e
commit a19eda0f49
1 changed files with 6 additions and 0 deletions

View File

@ -826,6 +826,9 @@ static int cdns_uart_startup(struct uart_port *port)
static void cdns_uart_shutdown(struct uart_port *port)
{
int status;
unsigned long flags;
spin_lock_irqsave(&port->lock, flags);
/* Disable interrupts */
status = readl(port->membase + CDNS_UART_IMR_OFFSET);
@ -835,6 +838,9 @@ static void cdns_uart_shutdown(struct uart_port *port)
/* Disable the TX and RX */
writel(CDNS_UART_CR_TX_DIS | CDNS_UART_CR_RX_DIS,
port->membase + CDNS_UART_CR_OFFSET);
spin_unlock_irqrestore(&port->lock, flags);
free_irq(port->irq, port);
}