From mboxrd@z Thu Jan 1 00:00:00 1970 From: Felipe Balbi Subject: [PATCH v4 15/21] serial: omap: unlock the port lock Date: Thu, 6 Sep 2012 15:45:34 +0300 Message-ID: <1346935540-1792-16-git-send-email-balbi@ti.com> References: <20120906122948.GC29202@arwen.pp.htv.fi> <1346935540-1792-1-git-send-email-balbi@ti.com> Return-path: In-Reply-To: <1346935540-1792-1-git-send-email-balbi@ti.com> Sender: linux-kernel-owner@vger.kernel.org To: Greg KH Cc: alan@linux.intel.com, Tony Lindgren , Kevin Hilman , Linux OMAP Mailing List , Linux ARM Kernel Mailing List , linux-serial@vger.kernel.org, Linux Kernel Mailing List , Santosh Shilimkar , Shubhrajyoti Datta , Sourav Poddar , Ruchika Kharwar , Pavan Savoy , Vijay Badawadagi , Felipe Balbi List-Id: linux-omap@vger.kernel.org From: Ruchika Kharwar 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 Signed-off-by: Ruchika Kharwar Signed-off-by: Pavan Savoy Signed-off-by: Vijay Badawadagi Signed-off-by: Felipe Balbi --- drivers/tty/serial/omap-serial.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c index d244163..9e4419c 100644 --- a/drivers/tty/serial/omap-serial.c +++ b/drivers/tty/serial/omap-serial.c @@ -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); -- 1.7.12.rc3