Commit 0324a821 authored Sep 06, 2012 by Ruchika Kharwar Committed by Greg Kroah-Hartman Sep 06, 2012

serial: omap: unlock the port lock



This patch unlocks the port lock before calling a serial_core API
and re-acquires the port lock after calling it.
This patch fixes a system freeze issue seen when the serial_core
API uart_write_wakeup() eventually attempts to acquire the port lock
already acquired by omap serial interrupt handler.

Tested-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Ruchika Kharwar <ruchika@ti.com>
Signed-off-by: Pavan Savoy <pavan_savoy@ti.com>
Signed-off-by: Vijay Badawadagi <bvijay@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 52c5513d

drivers/tty/serial/omap-serial.c

+4 −1

Original line number	Diff line number	Diff line
		@@ -224,8 +224,11 @@ static void transmit_chars(struct uart_omap_port *up, unsigned int lsr)
		break;
		} while (--count > 0);

		if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
		if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) {
		spin_unlock(&up->port.lock);
		uart_write_wakeup(&up->port);
		spin_lock(&up->port.lock);
		}

		if (uart_circ_empty(xmit))
		serial_omap_stop_tx(&up->port);