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Subject[PATCH 10/11] Revert "serial: omap: unlock the port lock"
Date
This reverts commit 0324a821029e1f54e7a7f8fed48693cfce42dc0e.

That commit tried to fix a deadlock problem when using
hci_ldisc, but it turns out the bug was in hci_ldsic
all along where it was calling ->write() from within
->write_wakeup() callback.

The problem is that ->write_wakeup() was called with
port lock held and ->write() tried to grab the same
port lock.

Signed-off-by: Felipe Balbi <balbi@ti.com>
---
drivers/tty/serial/omap-serial.c | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
index b092d3d..be10e7e 100644
--- a/drivers/tty/serial/omap-serial.c
+++ b/drivers/tty/serial/omap-serial.c
@@ -380,11 +380,8 @@ static void transmit_chars(struct uart_omap_port *up, unsigned int lsr)
break;
} while (--count > 0);

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

if (uart_circ_empty(xmit))
serial_omap_stop_tx(&up->port);
--
1.9.1.286.g5172cb3


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