[PATCH 06/26] serial: Fix send_xchar() handlers
From: Peter Hurley <hidden>
Date: 2014-09-02 21:42:42
Also in:
lkml, sparclinux
Subsystem:
documentation, sparc serial drivers, the rest, tty layer and serial drivers · Maintainers:
Jonathan Corbet, "David S. Miller", Linus Torvalds, Greg Kroah-Hartman, Jiri Slaby
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: <redacted> Signed-off-by: Peter Hurley <redacted> --- Documentation/serial/driver | 2 ++ drivers/tty/serial/sunhv.c | 3 +++ drivers/tty/serial/sunsab.c | 3 +++ 3 files changed, 8 insertions(+)
diff --git a/Documentation/serial/driver b/Documentation/serial/driver
index 3bba1ae..ba64e4b 100644
--- a/Documentation/serial/driver
+++ b/Documentation/serial/driver@@ -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.
diff --git a/drivers/tty/serial/sunhv.c b/drivers/tty/serial/sunhv.c
index 20521db..25d43ce 100644
--- a/drivers/tty/serial/sunhv.c
+++ b/drivers/tty/serial/sunhv.c@@ -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) {
diff --git a/drivers/tty/serial/sunsab.c b/drivers/tty/serial/sunsab.c
index bb09920..c83b1c6 100644
--- a/drivers/tty/serial/sunsab.c
+++ b/drivers/tty/serial/sunsab.c@@ -459,6 +459,9 @@ 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);
--
2.1.0