Blackfin Serial Driver: Fix bug - Don't call tx_stop in tx_transfer.

Disable irq and return immediately.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 5 insertions, 1 deletions

diff --git a/drivers/serial/bfin_5xx.c b/drivers/serial/bfin_5xx.c
index 8d2d7570668..5e20f50342a 100644
--- a/drivers/serial/bfin_5xx.c
+++ b/drivers/serial/bfin_5xx.c
@@ -301,7 +301,11 @@ static void bfin_serial_tx_chars(struct bfin_serial_port *uart)
         bfin_serial_mctrl_check(uart);
 
         if (uart_circ_empty(xmit) || uart_tx_stopped(&uart->port)) {
-                bfin_serial_stop_tx(&uart->port);
+#ifdef CONFIG_BF54x
+                /* Clear TFI bit */
+                UART_PUT_LSR(uart, TFI);
+#endif
+                UART_CLEAR_IER(uart, ETBEI);
                 return;
         }