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| author | Peter Hurley <peter@hurleysoftware.com> | 2014-09-02 17:39:15 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-09-08 16:22:42 -0700 |
| commit | db106df32d679db151b48a09543b03ee41cb2580 (patch) | |
| tree | bef38581727c0696e7aac02df61ceb9a8a093685 | |
| parent | fba594a848f6f35417a358565086d22c533c19c8 (diff) | |
| download | linux-0-day-db106df32d679db151b48a09543b03ee41cb2580.tar.gz linux-0-day-db106df32d679db151b48a09543b03ee41cb2580.tar.xz | |
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>
| -rw-r--r-- | Documentation/serial/driver | 2 | ||||
| -rw-r--r-- | drivers/tty/serial/sunhv.c | 3 | ||||
| -rw-r--r-- | drivers/tty/serial/sunsab.c | 3 |
3 files changed, 8 insertions, 0 deletions
diff --git a/Documentation/serial/driver b/Documentation/serial/driver index 3bba1aeb799c3..ba64e4b892e91 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 20521db2189fb..25d43ce8b3187 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 b9598b227a45b..0af75f8b98a49 100644 --- a/drivers/tty/serial/sunsab.c +++ b/drivers/tty/serial/sunsab.c @@ -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); |