@@ -140,6 +140,8 @@ hardware.
will append the character to the circular buffer and then call
start_tx() / stop_tx() to flush the data out.
+ Do not transmit if ch == '\0' (__DISABLED_CHAR).
+
Locking: none.
Interrupts: caller dependent.
@@ -268,6 +268,9 @@ static void sunhv_send_xchar(struct uart_port *port, char ch)
unsigned long flags;
int limit = 10000;
+ if (ch == __DISABLED_CHAR)
+ return;
+
spin_lock_irqsave(&port->lock, flags);
while (limit-- > 0) {
@@ -468,6 +468,9 @@ static void sunsab_send_xchar(struct uart_port *port, char ch)
struct uart_sunsab_port *up = (struct uart_sunsab_port *) port;
unsigned long flags;
+ if (ch == __DISABLED_CHAR)
+ return;
+
spin_lock_irqsave(&up->port.lock, flags);
sunsab_tec_wait(up);
This is a note to let you know that I've just added the patch titled serial: Fix send_xchar() handlers to my tty git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty.git in the tty-next branch. The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.) The patch will also be merged in the next major kernel release during the merge window. If you have any questions about this process, please let me know. From db106df32d679db151b48a09543b03ee41cb2580 Mon Sep 17 00:00:00 2001 From: Peter Hurley <peter@hurleysoftware.com> Date: Tue, 2 Sep 2014 17:39:15 -0400 Subject: serial: Fix send_xchar() handlers START_CHAR() & STOP_CHAR() can be disabled if set to '\0' (__DISABLED_CHAR). UART drivers which define a send_xchar() handler must not transmit __DISABLED_CHAR. Document requirement. Affected drivers: sunsab sunhv cc: David S. Miller <davem@davemloft.net> cc: <sparclinux@vger.kernel.org> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> --- Documentation/serial/driver | 2 ++ drivers/tty/serial/sunhv.c | 3 +++ drivers/tty/serial/sunsab.c | 3 +++ 3 files changed, 8 insertions(+)