[PATCH 1/2] tty_port,usb-console: Fix usb serial console open/close regression

[PATCH 1/2] tty_port,usb-console: Fix usb serial console open/close regression

[Jason Wessel]

Commit e1108a63e10d344284011cccc06328b2cd3e5da3 ("usb_serial: Use the
shutdown() operation") breaks the ability to use a usb console
starting in 2.6.33.  This was observed when using
console=ttyUSB0,115200 as a boot argument with an FTDI device.  The
error is:

ftdi_sio ttyUSB0: ftdi_submit_read_urb - failed submitting read urb, error -22

The handling of the ASYNCB_INITIALIZED changed in 2.6.32 such that in
tty_port_shutdown() it always clears the flag if it is set.  The fix
is to add a variable to the tty_port struct to indicate when the tty
port is a console.

CC: Greg Kroah-Hartman <gregkh@suse.de>
CC: Alan Cox <alan@linux.intel.com>
CC: Alan Stern <stern@rowland.harvard.edu>
CC: Oliver Neukum <oliver@neukum.org>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: linux-usb@vger.kernel.org
CC: linux-kernel@vger.kernel.org
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
 drivers/char/tty_port.c      |    2 +-
 drivers/usb/serial/console.c |    1 +
 include/linux/tty.h          |    1 +
 3 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/drivers/char/tty_port.c b/drivers/char/tty_port.c
index be492dd..a3bd1d0 100644
--- a/drivers/char/tty_port.c
+++ b/drivers/char/tty_port.c
@@ -119,7 +119,7 @@ EXPORT_SYMBOL(tty_port_tty_set);
 static void tty_port_shutdown(struct tty_port *port)
 {
 	mutex_lock(&port->mutex);
-	if (port->ops->shutdown &&
+	if (port->ops->shutdown && !port->console &&
 		test_and_clear_bit(ASYNCB_INITIALIZED, &port->flags))
 			port->ops->shutdown(port);
 	mutex_unlock(&port->mutex);
diff --git a/drivers/usb/serial/console.c b/drivers/usb/serial/console.c
index b22ac32..f347da2 100644
--- a/drivers/usb/serial/console.c
+++ b/drivers/usb/serial/console.c
@@ -181,6 +181,7 @@ static int usb_console_setup(struct console *co, char *options)
 	/* The console is special in terms of closing the device so
 	 * indicate this port is now acting as a system console. */
 	port->console = 1;
+	port->port.console = 1;
 
 	mutex_unlock(&serial->disc_mutex);
 	return retval;
diff --git a/include/linux/tty.h b/include/linux/tty.h
index d96e588..a42d7a6 100644
--- a/include/linux/tty.h
+++ b/include/linux/tty.h
@@ -223,6 +223,7 @@ struct tty_port {
 	wait_queue_head_t	close_wait;	/* Close waiters */
 	wait_queue_head_t	delta_msr_wait;	/* Modem status change */
 	unsigned long		flags;		/* TTY flags ASY_*/
+	unsigned char		console:1;	/* port is a console */
 	struct mutex		mutex;		/* Locking */
 	struct mutex		buf_mutex;	/* Buffer alloc lock */
 	unsigned char		*xmit_buf;	/* Optional buffer */
-- 
1.5.4.3

[PATCH 2/2] usb-serial: Use tty_port version console instead of usb_serial_port

[Jason Wessel]

Replace all instances of using the console variable in struct
usb_serial_port with the struct tty_port version.

CC: Greg Kroah-Hartman <gregkh@suse.de>
CC: Alan Cox <alan@linux.intel.com>
CC: Alan Stern <stern@rowland.harvard.edu>
CC: Oliver Neukum <oliver@neukum.org>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: linux-usb@vger.kernel.org
CC: linux-kernel@vger.kernel.org
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
---
 drivers/usb/serial/console.c    |    5 ++---
 drivers/usb/serial/ftdi_sio.c   |    2 +-
 drivers/usb/serial/generic.c    |    4 ++--
 drivers/usb/serial/pl2303.c     |    2 +-
 drivers/usb/serial/usb-serial.c |    2 +-
 include/linux/usb/serial.h      |    2 --
 6 files changed, 7 insertions(+), 10 deletions(-)

diff --git a/drivers/usb/serial/console.c b/drivers/usb/serial/console.c
index f347da2..4ea64fe 100644
--- a/drivers/usb/serial/console.c
+++ b/drivers/usb/serial/console.c
@@ -180,7 +180,6 @@ static int usb_console_setup(struct console *co, char *options)
 	--port->port.count;
 	/* The console is special in terms of closing the device so
 	 * indicate this port is now acting as a system console. */
-	port->console = 1;
 	port->port.console = 1;
 
 	mutex_unlock(&serial->disc_mutex);
@@ -217,7 +216,7 @@ static void usb_console_write(struct console *co,
 
 	dbg("%s - port %d, %d byte(s)", __func__, port->number, count);
 
-	if (!port->console) {
+	if (!port->port.console) {
 		dbg("%s - port not opened", __func__);
 		return;
 	}
@@ -313,7 +312,7 @@ void usb_serial_console_exit(void)
 {
 	if (usbcons_info.port) {
 		unregister_console(&usbcons);
-		usbcons_info.port->console = 0;
+		usbcons_info.port->port.console = 0;
 		usbcons_info.port = NULL;
 	}
 }
diff --git a/drivers/usb/serial/ftdi_sio.c b/drivers/usb/serial/ftdi_sio.c
index 6af0dfa..95ec748 100644
--- a/drivers/usb/serial/ftdi_sio.c
+++ b/drivers/usb/serial/ftdi_sio.c
@@ -2073,7 +2073,7 @@ static int ftdi_process_packet(struct tty_struct *tty,
 		return 0;	/* status only */
 	ch = packet + 2;
 
-	if (!(port->console && port->sysrq) && flag == TTY_NORMAL)
+	if (!(port->port.console && port->sysrq) && flag == TTY_NORMAL)
 		tty_insert_flip_string(tty, ch, len);
 	else {
 		for (i = 0; i < len; i++, ch++) {
diff --git a/drivers/usb/serial/generic.c b/drivers/usb/serial/generic.c
index 89fac36..4dea9d7 100644
--- a/drivers/usb/serial/generic.c
+++ b/drivers/usb/serial/generic.c
@@ -437,7 +437,7 @@ static void flush_and_resubmit_read_urb(struct usb_serial_port *port)
 	/* The per character mucking around with sysrq path it too slow for
 	   stuff like 3G modems, so shortcircuit it in the 99.9999999% of cases
 	   where the USB serial is not a console anyway */
-	if (!port->console || !port->sysrq)
+	if (!port->port.console || !port->sysrq)
 		tty_insert_flip_string(tty, ch, urb->actual_length);
 	else {
 		/* Push data to tty */
@@ -556,7 +556,7 @@ void usb_serial_generic_unthrottle(struct tty_struct *tty)
 int usb_serial_handle_sysrq_char(struct tty_struct *tty,
 			struct usb_serial_port *port, unsigned int ch)
 {
-	if (port->sysrq && port->console) {
+	if (port->sysrq && port->port.console) {
 		if (ch && time_before(jiffies, port->sysrq)) {
 			handle_sysrq(ch, tty);
 			port->sysrq = 0;
diff --git a/drivers/usb/serial/pl2303.c b/drivers/usb/serial/pl2303.c
index 73d5f34..1891cfb 100644
--- a/drivers/usb/serial/pl2303.c
+++ b/drivers/usb/serial/pl2303.c
@@ -1056,7 +1056,7 @@ static void pl2303_push_data(struct tty_struct *tty,
 	if (line_status & UART_OVERRUN_ERROR)
 		tty_insert_flip_char(tty, 0, TTY_OVERRUN);
 
-	if (tty_flag == TTY_NORMAL && !(port->console && port->sysrq))
+	if (tty_flag == TTY_NORMAL && !(port->port.console && port->sysrq))
 		tty_insert_flip_string(tty, data, urb->actual_length);
 	else {
 		int i;
diff --git a/drivers/usb/serial/usb-serial.c b/drivers/usb/serial/usb-serial.c
index 3873660..75a5e0c 100644
--- a/drivers/usb/serial/usb-serial.c
+++ b/drivers/usb/serial/usb-serial.c
@@ -328,7 +328,7 @@ static void serial_cleanup(struct tty_struct *tty)
 	/* The console is magical.  Do not hang up the console hardware
 	 * or there will be tears.
 	 */
-	if (port->console)
+	if (port->port.console)
 		return;
 
 	dbg("%s - port %d", __func__, port->number);
diff --git a/include/linux/usb/serial.h b/include/linux/usb/serial.h
index 0a458b8..b7682fe 100644
--- a/include/linux/usb/serial.h
+++ b/include/linux/usb/serial.h
@@ -66,7 +66,6 @@ enum port_dev_state {
  * @work: work queue entry for the line discipline waking up.
  * @throttled: nonzero if the read urb is inactive to throttle the device
  * @throttle_req: nonzero if the tty wants to throttle us
- * @console: attached usb serial console
  * @dev: pointer to the serial device
  *
  * This structure is used by the usb-serial core and drivers for the specific
@@ -106,7 +105,6 @@ struct usb_serial_port {
 	struct work_struct	work;
 	char			throttled;
 	char			throttle_req;
-	char			console;
 	unsigned long		sysrq; /* sysrq timeout */
 	struct device		dev;
 	enum port_dev_state	dev_state;
-- 
1.5.4.3